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171.
A series of new N-type (Ca(v)2.2) calcium channel blockers derived from the 'hit' structures 2-(3-bromo-4-fluorophenyl)-3-(2-pyridin-2-ylethyl)thiazolidin-4-one 9 and its 2-[4-(4-bromophenyl)pyridin-3-yl]-3-isobutyl analogue 10 is described. Extensive SAR studies using a range of synthetic approaches resulted in novel, patented compounds with IC50 values of up to 0.2 microM in an in vitro IMR32 assay, and selectivities for N/L of up to 30-fold. The new compounds described have potential in treatment of neuropathic pain.  相似文献   
172.
The extent to which no‐take marine reserves can benefit anadromous species requires examination. Here, we used acoustic telemetry to investigate the spatial behavior of anadromous brown trout (sea trout, Salmo trutta) in relation to a small marine reserve (~1.5 km2) located inside a fjord on the Norwegian Skagerrak coast. On average, sea trout spent 42.3 % (±5.0% SE) of their time in the fjord within the reserve, a proportion similar to the area of the reserve relative to that of the fjord. On average, sea trout tagged inside the reserve received the most protection, although the level of protection decreased marginally with increasing home range size. Furthermore, individuals tagged outside the reserve received more protection with increasing home range size, potentially opposing selection toward smaller home range sizes inflicted on fish residing within reserves, or through selective fishing methods like angling. Monthly sea trout home ranges in the marine environment were on average smaller than the reserve, with a mean of 0.430 (±0.0265 SE) km2. Hence, the reserve is large enough to protect the full home range of some individuals residing in the reserve. Synthesis and applications: In general, the reserve protects sea trout to a varying degree depending on their individual behavior. These findings highlight evolutionary implications of spatial protection and can guide managers in the design of marine reserves and networks that preserve variation in target species' home range size and movement behavior.  相似文献   
173.
We developed primers for two dinucleotide and eight tetranucleotide microsatellite loci in a marine fish, the ling (Molva molva). All markers were obtained from partial genomic DNA libraries and characterized in 55 unrelated individuals from one putative population. The number of alleles ranged from five to 24 (average 10.5) per locus, and the observed heterozygosity ranged from 0.218 to 0.981 (average 0.643). No loci amplified in two other gadoid species tested, the Atlantic cod (Gadus morhua) and the tusk (Brosme brosme).  相似文献   
174.
This study documents horizontal distribution and demography of Antarctic krill (Euphausia superba) from the Southern Ocean during January–March 2008. The cruise predominantly occurred in CCAMLR Subarea 48.6, where knowledge about the ecosystem is limited. E. superba were not found north of 52°S. The biomass, estimated from trawl catches, was highest (63.09 g/m2) at a station 680 km southeast of Bouvetøya and at two stations 1,400 and 600 km southeast and southwest of Bouvetøya, 54.67 and 61.38 g/m2, respectively. Body length ranged from 19 to 61 mm (N = 8,538), with a mean of 42.0 ± 6.4 mm (SD). The overall sex ratio was 1:1, 46.2% males (13.2% adults and 33.0% subadults), 46.1% females (33.6% adults and 12.5% subadults), while 7.5% were juveniles. Trawl stations dominated by adults were found west and north of Bouvetøya. Stations with high proportions of subadults and juveniles were mainly found southeast of the island. Four cluster groups were differentiated: analyzing data on krill sex proportions, maturity stages, hydrography, nutrients and chlorophyll concentrations. Two groups represented stations located in the northern part of the study area, where E. superba were absent; water temperatures were higher and the nutrient concentrations lower compared to the groups where E. superba were present. This study shows that bathymetric features like the North Weddell Ridge including Bouvetøya are important for concentrating krill probably due to water mass characteristics and advective processes which influence regional krill demography. The southern regions of CCAMLR sector 48.6 are essential for understanding regional krill recruitment and production.  相似文献   
175.
Heterozygous elastin gene mutations cause autosomal dominant cutis laxa associated with emphysema and aortic aneurysms. To investigate the molecular mechanisms leading to cutis laxa in vivo, we generated transgenic mice by pronuclear injection of minigenes encoding normal human tropoelastin (WT) or tropoelastin with a cutis laxa mutation (CL). Three independent founder lines of CL mice showed emphysematous pulmonary airspace enlargement. No consistent dermatological or cardiovascular pathologies were observed. One CL and one WT line were selected for detailed studies. Both mutant and control transgenic animals showed elastin deposition into pulmonary elastic fibers, indicated by increased desmosine levels in the lung and by colocalization of transgenic and endogenous elastin by immunostaining. CL mice showed increased static lung compliance and decreased stiffness of lung tissue. In addition, markers of transforming growth factor-β (TGFβ) signaling and the unfolded protein response (UPR) were elevated together with increased apoptosis in the lungs of CL animals. We conclude that the synthesis of mutant elastin in CL activates multiple downstream disease pathways by triggering a UPR, altered mechanical signaling, increased release of TGFβ and apoptosis. We propose that the combined effects of these processes lead to the development of an emphysematous pulmonary phenotype in CL.  相似文献   
176.
In order to determine the occurrence, distribution, and significance of mold species in groundwater- and surface water-derived drinking water in Norway, molds isolated from 273 water samples were identified. Samples of raw water, treated water, and water from private homes and hospital installations were analyzed by incubation of 100-ml membrane-filtered samples on dichloran-18% glycerol agar. The total count (number of CFU per 100 ml) of fungal species and the species diversity within each sample were determined. The identification of mold species was based on morphological and molecular methods. In total, 94 mold species belonging to 30 genera were identified. The mycobiota was dominated by species of Penicillium, Trichoderma, and Aspergillus, with some of them occurring throughout the drinking water system. Several of the same species as isolated from water may have the potential to cause allergic reactions or disease in humans. Other species are common contaminants of food and beverages, and some may cause unwanted changes in the taste or smell of water. The present results indicate that the mycobiota of water should be considered when the microbiological safety and quality of drinking water are assessed. In fact, molds in drinking water should possibly be included in the Norwegian water supply and drinking water regulations.  相似文献   
177.
It is of interest to document the moelcular docking analysis of SARS-CoV-2 linked RNA dependent RNA polymerase (RdRp) with compounds from Plectranthus amboinicus. Hence, we report the binding features of rutin, Luteolin, Salvianolic acid A, Rosmarinic acid and p-Coumaric acid with the target protein SARS-CoV-2 linked RNA dependent RNA polymerase (RdRp) for further consideration.  相似文献   
178.
Cornulin (CRNN) is linked with tumour progression. Therefore, it is of interest to document data on the molecular modeling of cornulin (CRNN) for docking with phytocompounds (Pyrazinamide, Anisotine, Vasicinone, Vasicoline) from Justicia adhatoda L. Thus, we document the optimal binding features of these compounds with the cornulin model for further consideration.  相似文献   
179.
We have isolated from a lambda gt10 cDNA library a clone lambda GTH4 which encodes a human liver glutathione S-transferase Hb subunit, designated as subunit 4. Expression of this cDNA in E. coli and subsequent purification and immunoblotting analysis provided a definitive assignment of a structure and function relationship. RNA blot hybridization with human liver poly(A) RNA revealed a single band of approximately 1200 nucleotides, comparable in size to the rat brain Yb3 mRNA. Divergence analysis of amino acid replacement sites in subunit 4 relative to the four rat Yb subunits revealed that it is most closely related to the brain-specific Yb3 subunit. This conclusion is further substantiated by the nucleotide sequence homology between lambda GTH4 and the Yb3 cDNA in their 3' untranslated region. In situ chromosome mapping has located this glutathione S-transferase gene in the region of p31 on chromosome 1. Results from many laboratories, including ours, indicate that the human glutathione S-transferases are encoded by a gene superfamily which is located on at least two different chromosomes.  相似文献   
180.
The coarse of growth and cell division in synchronized cultures of Chlorella pyrenoidosa was studied after the addition of metabolic inhibitors at differing times during the cell cycle (14 h light - 10 h darkness with nitrate as nitrogen source. 12 h light: 12 h darkness with urea as nitrogen source). Dinitrophenol (DNP) added to a final concentration of 0.3 mM at any time in the synchronization cycle, the compound remaining in the suspension from the time of addition to the end of the dark period, inhibited spore formation completely. Growth measured as increase in cell volume was less sensitive to the action of the inhibitor. Chloramphenicol (CAP) added dining the 0–5 h interval to a final concentration of 0.1 mM resulted in 80 per cent inhibition of cell division. Similar treatment started at successive times thereafter resulted in a gradual decrease of the inhibition. Treatment at the 14th hour and during the dark period did not affect the sporulation. Similar experiments with 0.9 mM puromycin added at various times during the illumination period gave almost complete inhibition of cell division, while the growth was reduced by only 25 per cent. para-Fluorophenylalanine (p-FPhe) at 3.3 × 10?2 mM stopped cell division nearly completely irrespective of addition time in the light period. Addition during the dark period also prevented an increase in the number of tree cells. In this case about half of the cells produced spores which were not released. It is concluded that DNP inhibits all stages of preparation for cell division, as well as the division process itself. With CAP a genuine transition point of preparation for cell division was observed, although its interpretation as related to protein synthesis is somewhat uncertain. With puromycin and p-FPhe no transitions were observed.  相似文献   
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