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101.
The myosin light chain kinase (MYLK) gene encodes both smooth muscle and nonmuscle cell isoforms. Recently, polymorphisms in MYLK have been reported to be associated with several diseases. To examine the genetic effects of polymorphisms on the risk of asthma and related phenotypes, we scrutinized MYLK by re-sequencing/genotyping and statistical analysis in Korean population (n = 1,015). Seventeen common polymorphisms located in or near exons, having pairwise r 2 values less than 0.25, were genotyped. Our statistical analysis did not replicate the associations with the risk of asthma and log-transformed total IgE levels observed among African descendant populations. However, two SNPs in intron 16 (+89872C > G and +92263T >C), which were in tight LD (|D′| = 0.99), revealed significant association with log-transformed blood eosinophil level even after correction multiple testing (P = 0.002/P corr = 0.01 and P = 0.002/P corr = 0.01, respectively). The log-transformed blood eosinophil levels were higher in individuals bearing the minor alleles for +89872C > G and +92263T > C, than in those bearing other allele. In additional subgroup analysis, the genetic effects of both SNPs were much more apparent among asthmatic patients and atopic asthma patients. Among atopic asthma patients, the log-transformed blood eosinophil levels were proportionally increased by gene-dose dependent manner of in both +89872C > G and +92263T > C (P = 0.0002 and P = 0.00007, respectively). These findings suggest that MYLK polymorphisms might be among the genetic factors underlying differential increases of blood eosinophil levels among asthmatic patients. Further biological and/or functional studies are needed to confirm our results.  相似文献   
102.
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   
103.

Background

The effects of corticosteroid-based therapy in patients with idiopathic nonspecific interstitial pneumonia (iNSIP), and factors affecting treatment outcome, are not fully understood. We aimed to investigate the long-term treatment response and factors affecting the treatment outcome in iNSIP patients from a multi-center study in Korea.

Methods

The Korean interstitial lung disease (ILD) Study Group surveyed ILD patients from 2003 to 2007. Patients were divided into two groups to compare the treatment response: response group (forced vital capacity (FVC) improves ≥10% after 1 year) and non-response group (FVC <10%). Factors affecting treatment response were evaluated by multivariate logistic regression analysis.

Results

A total of 261 patients with iNSIP were enrolled, and 95 patients were followed-up for more than 1 year. Corticosteroid treatment was performed in 86 patients. The treatment group showed a significant improvement in lung function after 1-year: FVC, 10.0%; forced expiratory volume (FEV1), 9.8%; diffusing capacity of the lung for carbon monoxide (DLco), 8.4% (p?<?0.001). Sero-negative anti-nuclear antibody (ANA) was significantly related with lung function improvement. Sero-positivity ANA was significantly lower in the response group (p?=?0.013), compared to that in the non-response group. A shorter duration of respiratory symptoms at diagnosis was significantly associated with a good response to treatment (p?=?0.018).

Conclusion

Treatment with corticosteroids and/or immunosuppressants improved lung function in iNSIP patients, which was more pronounced in sero-negative ANA and shorter symptom duration patients. These findings suggest that early treatment should be considered in iNSIP patients, even in an early disease stage.
  相似文献   
104.
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   
105.
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   
106.
107.
108.
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   
109.
Genetic maladaptation of coastal Douglas-fir seedlings to future climates   总被引:1,自引:0,他引:1  
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   
110.
The value of fine catheter aspiration cytology in the diagnosis of metastatic tumours is illustrated by a case of pleomorphic giant cell carcinoma of the pancreas which had metastasized to the peritoneal cavity. The finding of unequivocal malignant cells obviated the need for further diagnostic procedures. Electron microscopy and immunostaining further substantiated the light microscopic cytodiagnosis and identified the tumour type and source of the primary tumour. Furthermore, subsequent cell block preparation from the aspirated material demonstrated the histological features of this tumour.  相似文献   
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