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91.
GUY M. L. PERRY TIM L. KING JR
ME ST.‐CYR MANON VALCOURT LOUIS BERNATCHEZ 《Molecular ecology resources》2005,5(2):346-351
The brook charr (Salvelinus fontinalis; Osteichthyes: Salmonidae) is a phenotypically diverse fish species inhabiting much of North America. But relatively few genetic diagnostic resources are available for this fish species. We isolated 41 microsatellites from S. fontinalis polymorphic in one or more species of salmonid fish. Thirty‐seven were polymorphic in brook charr, 15 in the congener Arctic charr (Salvelinus alpinus) and 14 in the lake charr (Salvelinus namaycush). Polymorphism was also relatively high in Oncorhynchus, where 21 loci were polymorphic in rainbow trout (Oncorhynchus mykiss) and 16 in cutthroat trout (Oncorhynchus clarkii) but only seven and four microsatellite loci were polymorphic in the more distantly related lake whitefish (Coregonus clupeaformis) and Atlantic salmon (Salmo salar), respectively. One duplicated locus (Sfo228Lav) was polymorphic at both duplicates in S. fontinalis. 相似文献
92.
93.
Spanevello RM de Souza Wyse AT Mazzanti CM Schmatz R Stefanello N Gonçalves JF Bagatini M Battisti V Morsch VM Schetinger MR 《Neurochemical research》2008,33(6):1129-1137
Guanidinoacetate methyltransferase (GAMT) deficiency is a disorder of creatine metabolism characterized by low plasma creatine
concentrations in combination with elevated guanidinoacetate (GAA) concentrations. The aim of this work was to investigate
the in vitro effect of guanidinoacetate in NTPDase, 5′-nucleotidase and acetylcholinesterase activities in the synaptosomes,
platelets and blood of rats. The results showed that in synaptosomes the NTPDase and 5′-nucleotidase activities were inhibited
significantly in the presence of GAA at concentrations of 50, 100, 150 and 200 μM (P < 0.05). However, in platelets GAA at the same concentrations caused a significant increase in the activities of these two
enzymes (P < 0.05). In relation to the acetylcholinesterase activity, GAA caused a significant inhibition in the activity of this enzyme
in blood at concentrations of 150 and 200 μM (P < 0.05), but did not alter the acetylcholinesterase activity in synaptosomes from the cerebral cortex. Our results suggest
that alterations caused by GAA in the activities of these enzymes may contribute to the understanding of the neurological
dysfunction of GAMT-deficient patients. 相似文献
94.
This study examined the application of previously characterized microparticles composed of hyaluronan (HA) and chitosan hydroglutamate (CH) as well as novel microparticles consisting of both polymers (HA/CH) to improve the nasal delivery of a model drug. The rabbit bioavailabilities of gentamicin incorporated in HA, CH, and HA/CH microparticles were increased 23-, 31-, and 42-fold, respectively, compared with the control intranasal solution of gentamicin, indicating that all test microparticles were retained for longer periods on the nasal mucosa of the rabbits as supported by previous in vitro dissolution as well as frog palate mucoadhesion studies, thereby improving drug absorption. The higher bioavailabilities of CH-based formulations (CH and HA/CH) suggest the penetration-enhancing effects of CH may also be partially responsible for the improvement. A model was developed, based on a glass impinger device, to deliver dry powder formulations reproducibly onto the surface of cultured cell monolayers. In vitro permeability and fluorescence microscopy studies on the tight junctions of the 16HBE14o- cell lines further confirmed the ability of CH-based formulations to enhance penetration. Furthermore, the in vitro absorption profile from cell culture studies was consistent with those determined from in vivo studies. The complementary effect from the mucoadhesive nature of HA coupled with the penetration-enhancing effects of CH makes the novel HA/CH formulation a promising nasal delivery system. 相似文献
95.
Tähtinen P Sinkkonen J Klika KD Nieminen V STájer G Szakonyi Z FüLöp F Pihlaja K 《Chirality》2002,14(2-3):187-198
Four 7a-methyl octa(or hexa)hydrocyclopenta[d][1,3]oxazines, five 8a-methyl octa(or hexa)hydro[3,1]benzoxazines, two 6-phenyl hexahydro[3,1]benzoxazinones, and 8a-methyl hexahydro[1,3]benzoxazinone, all cis-fused, were prepared and their stereostructures studied by various one- and two-dimensional (1)H, (13)C, and (15)N NMR spectroscopic methods. In solution, the cyclopentane-fused 2-oxo derivatives and the 1,3-benzoxazinone were found to attain exclusively the N-in/O-in conformation, whereas the 6-phenyl 2-oxo/thioxo derivatives were found to be present predominantly in the N-out conformation. The C-2 unsubstituted and the 2-oxo/thioxo 7a/8a-methyl derivatives were all present in solution as a rapidly interconverting equilibrium of the N-in and N-out conformations. The C-2 methyl derivatives were each found to be interconvertable mixtures of epimers (at C-2) with the N-in conformer predominating for one epimer and the N-out conformer predominating for the other, with both predominating conformers having the C-2 methyl group equatorially orientated. The substituent on the nitrogen (H or Me) was found to be always predominantly equatorial with respect to the heteroring, except for the epimeric 2-methyl derivatives with N-out conformations where steric constraints and the generalized anomeric effect resulted in the axial orientation of the C-2 methyl being favored. 相似文献
96.
Nadia Mushtaq Roberta Schmatz Mushtaq Ahmed Luciane Belmonte Pereira Pauline da Costa Karine Paula Reichert Diéssica Dalenogare Luana Paula Pelinson Juliano Marchi Vieira Naiara Stefanello Lizielle Souza de Oliveira Nadia Mulinacci Maria Bellumori Vera Maria Morsch Maria Rosa Schetinger 《Journal of physiology and biochemistry》2015,71(4):743-751
97.
Bona Natália Pontes Soares Mayara Sandrielly Pereira Pedra Nathalia Stark Spohr Luiza da Silva dos Santos Francieli de Farias Alana Seixas Alvez Fernando Lopez de Moraes Meine Bernardo Luduvico Karina Pereira Spanevello Roselia Maria Stefanello Francieli Moro 《Neurochemical research》2022,47(6):1541-1552
Neurochemical Research - Glioblastoma (GB) is a highly aggressive and invasive brain tumor; its treatment remains palliative. Tannic acid (TA) is a polyphenol widely found in foods and possesses... 相似文献
98.
99.
The phenology of spring migration depends on the severity of the preceding winter and approaching spring. This severity can be quantified using the North Atlantic Oscillation (NAO) index; positive values indicate mild winters. Although milder winters are correlated with earlier migration in many birds in temperate regions, few studies have addressed how climate‐induced variation in spring arrival relates to breeding success. In northern Europe, the NAO‐index correlates with ice cover and timing of ice break‐up of the Baltic Sea. Ice cover plays an important role for breeding waterfowl, since the timing of ice break‐up constrains both spring arrival and onset of breeding. We studied the effects of the winter‐NAO‐index and timing of ice break‐up on spring migration, laying date, clutch size, female body condition at hatching and fledging success of a short‐distance migrant common eider (Somateria mollissima) population from SW Finland, the Baltic Sea, 1991–2004 (migration data 1979–2004). We also examined the correlation between the NAO‐index and the proportion of juvenile eiders in the Danish hunting bag, which reflects the breeding success on a larger spatial scale. The body condition of breeding females and proportion of juveniles in the hunting bag showed significant positive correlations with the NAO, whereas arrival dates showed positive correlations and clutch size and fledging success showed negative correlations with the timing of ice break‐up. The results suggest that climate, which also affects ice conditions, has an important effect on the fledging success of eiders. Outbreaks of duckling disease epidemics may be the primary mechanism underlying this effect. Eider females are in poorer condition after severe winters and cannot allocate as much resources to breeding, which may impair the immune defense of ducklings. Global climate warming is expected to increase the future breeding success of eiders in our study population. 相似文献
100.
Climates are expected to warm considerably over the next century, resulting in expectations that plant populations will not be adapted to future climates. We estimated the risk of maladaptation of current populations of coastal Douglas-fir (Pseudotsuga menziesii var. menziesii) to future climates as the proportion of nonoverlap between two normal distributions where the means and genetic variances of current and future populations are determined from genecological models derived from seedling common garden studies. The risk of maladaptation was large for most traits when compared with the risk associated with current transfers within seed zones, particularly for the more drastic climate change scenario. For example, the proportion of nonoverlap for a composite trait representing bud set, emergence, growth, and root : shoot ratio was as high as 0.90. We recommend augmenting within-population variation by mixing local populations with some proportion of populations from lower elevations and further south. Populations expected to be adapted to climates a century from now come from locations as far down in elevation as 450–1130 m and as far south in latitude as 1.8–4.9°. 相似文献