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21.
The morphology, anatomy and distribution of glandular trichomes on the aerial organs of Salvia argentea L. has been investigated. Two morphologically distinct types of glandular trichomes were determined. Capitate glandular trichomes forming a base 1–7 celled, a stalk 1–5 celled or no stalk and a head uni- or bicellular had various types. In capitate trichomes, the neck cell that has an important role especially for xeroformic plants, acting to prevent the backflow of secreted substance through the apoplast has been distinctively observed in the investigated species. The capitate trichomes were present abundantly on all aerial organs of S. argentea. Peltate glandular trichomes had a large secretory head forming 1–5, 8 central and 8–10, 12, 14 peripheral cells. Peltate trichomes are present on all aerial organs, except petiole, being the most abundant on calyx and corolla. Results were shown by tables and photographs.  相似文献   
22.
Altered Bone Morphogenetic Protein (BMP) signaling leads to multiple developmental defects, including brachydactyly and deafness. Here we identify chondroitin synthase 1 (CHSY1) as a potential mediator of BMP effects. We show that loss of human CHSY1 function causes autosomal-recessive Temtamy preaxial brachydactyly syndrome (TPBS), mainly characterized by limb malformations, short stature, and hearing loss. After mapping the TPBS locus to chromosome 15q26-qterm, we identified causative mutations in five consanguineous TPBS families. In zebrafish, antisense-mediated chsy1 knockdown causes defects in multiple developmental processes, some of which are likely to also be causative in the etiology of TPBS. In the inner ears of zebrafish larvae, chsy1 is expressed similarly to the BMP inhibitor dan and in a complementary fashion to bmp2b. Furthermore, unrestricted Bmp2b signaling or loss of Dan activity leads to reduced chsy1 expression and, during epithelial morphogenesis, defects similar to those that occur upon Chsy1 inactivation, indicating that Bmp signaling affects inner-ear development by repressing chsy1. In addition, we obtained strikingly similar zebrafish phenotypes after chsy1 overexpression, which might explain why, in humans, brachydactyly can be caused by mutations leading either to loss or to gain of BMP signaling.  相似文献   
23.
We aimed to investigate the association between manganese superoxide dismutase (MnSOD) Ala-9-Val gene polymorphism and the initiation and/or progression of prostate cancer (PCa) as well as to evaluate its potential interactions with advanced age and smoking status. MnSOD Ala-9-Val gene polymorphism was carried out in 134 (mean age 64.1 ± 7.48) PCa patients and 159 (mean age 62.5 ± 7.53) healthy controls with serum prostate specific antigen (PSA) levels (<4 ng/ml) and normal digital rectal examination (DRE) findings in this prospectively designed study. PCa patients were classified as low stage disease (T1 or T2 and N0M0 stages) and high stage disease (T3 or T4 and N0M0 or N1 or M1 stages). Genotypes for MnSOD Ala-9-Val gene polymorphism were identified by using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFPL). Despite lack of association between different genotypes of MnSOD Ala-9-Val gene polymorphism and the presence of PCa, patients with Ala/Ala genotype were at an increased risk of high stage disease compared with those with the Val/Val genotype [odds ratio (OR), 3.77; 95% CI, 1.30–10.94; P = 0.012]. However, no significant difference was observed in the distribution of each genotype among PCa patients, with respect to tumor grade. On the other hand, smoking status and aging did not seem to change the association between genotypes and PCa risk. Ala/Ala genotype of MnSOD polymorphism may have an effect on adverse features of PCa such as high stage disease.  相似文献   
24.
Homomorphic self‐incompatibility is a well‐studied example of a physiological process that is thought to increase population diversity and reduce the expression of inbreeding depression. Whereas theoretical models predict the presence of a large number of S‐haplotypes with equal frequencies at equilibrium, unequal allele frequencies have been repeatedly reported and attributed to sampling effects, population structure, demographic perturbation, sheltered deleterious mutations or selection pressure on linked genes. However, it is unclear to what extent unequal segregations are the results of gametophytic or sexual selection. Although these two forces are difficult to disentangle, testing S‐alleles in the offspring of controlled crosses provides an opportunity to separate these two phenomena. In this work, segregation and transmission of S‐alleles have been characterized in progenies of mixed donors and fully compatible pollinations under field conditions in Prunus avium. Seed set patterns and pollen performance have also been characterized. The results reveal paternal‐specific distorted transmission of S‐alleles in most of the crosses. Interestingly, S‐allele segregation within any given paternal or maternal S‐locus was random. Observations on pollen germination, pollen tube growth rate, pollen tube cohort size, seed set dynamics and transmission patterns strongly suggest post‐pollination, prezygotic sexual selection, with male–male competition as the most likely mechanism. According to these results, post‐pollination sexual selection takes precedence over frequency‐dependent selection in explaining unequal S‐haplotype frequencies.  相似文献   
25.
The objective of this study was to investigate the effects of different forms of Se supplementation on the antioxidant defense and glucose homeostasis in experimental diabetes. Sodium selenate (SS) or selenomethionine (SM) were administered (2 μmol Se kg−1 day−1) via orogastric route to streptozotocine (STZ)-induced diabetic rats in addition to basal diet for 12 weeks. Glucose levels in whole blood, glutathione peroxidase (GSH-Px) activity in erythrocytes, Se and fructosamine levels in plasma were evaluated monthly. Plasma Se levels increased significantly in all diabetic groups compared to basal measurements, being more prominent in SM group [p(SM3/SM0) = 0.018]. The increase in GSH-Px activities was significant at the end of the second month in SS [p(SS2/SS0) = 0.028], whereas at the end of the third month in SM the value was lower [p(SM3/SM0) = 0.018] and the unsupplemented diabetic control (DC) groups, p(DC3/DC0) = 0.012. Glucose increased significantly only in DC group. Fructosamine increased gradually in all diabetic groups, being significant in DC and SS groups. At the end of the third month, highest fructosamine levels were observed in SS group, which were significantly higher than the SM group [p(SM/SS) = 0.010]. In conclusion, Se augmented the antioxidant defense by increasing GSH-Px activity and this effect was more prominent when Se was supplemented as SM, which exerted positive effects also on glucose homeostasis.  相似文献   
26.
The Mutation‐Minimization Method (MuMi) to study the local response of proteins to point mutations has been introduced here. The heat shock protein Hsp70 as the test system since it displays features that have been studied in great detail has been used here. It has many conserved residues, serves several different functions on each of its domains, and displays interdomain allostery. For the analysis of spatial arrangement of residues within the protein, the network properties of the wild type (WT) protein as well as its all single alanine residue mutants using MuMi has been investigated. The measures to express the amount of change from the WT structure upon mutation and compare these deviations to find potential critical sites have been proposed. The functional significance of the potential sites to the parameter that uncovers them has been mapped. It was found that sites directly involved in binding were sensitive to mutations and were characterized by large displacements. On the other hand, sites that steer large conformational changes typically had increased reachability upon alanine mutations occurring elsewhere in the protein. Finally, residues that control communication within and between domains reside on the largest number of paths connecting pairs of residues in the protein. Proteins 2015; 83:2077–2090. © 2015 Wiley Periodicals, Inc.  相似文献   
27.

We aimed to show the effect of osteoporosis on sleep quality in 59 postmenopausal women. The participants’ bone-mineral density levels were measured by dual-energy X-ray absorptiometry (DEXA). According to their DEXA results, participants were divided into two groups as osteoporotics and controls. The Pittsburgh Sleep Quality Index (PSQI) was used to evaluate sleep quality. Fourteen osteoporotic women (43.8%) and four controls (14.8%) were “poor” sleepers (p < 0.05). Postmeno-pausal women with osteoporosis scored greater on the “sleep latency” and “sleep duration” components of PSQI than controls. According to the findings of our study, osteoporosis is a risk factor for poor sleep quality in postmenopausal women.

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28.
Purpose: Evidence indicates that free radicals are etiological factors in obstructive bladder disease. However, it is not clear which species of reactive oxygen or nitrogen species mediate the damage. The current studies were designed to determine if partial outlet obstruction in rabbits results in the generation of nitrotyrosine (NT). Materials and methods: Sixteen rabbits were separated into four groups of four. The rabbits in groups 1 and 2 underwent sham operation while rabbits in groups 3 and 4 underwent partial outlet obstruction. The rabbits in groups 1 and 3 were evaluated after 1 week of obstruction and the rabbits in groups 2 and 4 were evaluated after 2 weeks of obstruction. A separate group of four controls were evaluated simultaneously with the sham and obstructed rabbits. Four rabbits from each group were evaluated after 1 and 2 weeks of obstruction. Four control rabbits were also evaluated. Isolated strips were evaluated for contractile responses and NT content of the mucosa and muscle were quantitated by Western blot analysis. Results: (1) The mucosa contains both 42 and 62 kD proteins exhibiting a strong nitrotyrosine signal; the muscle presents a signal only at 62 kD. (2) The sham operations had no effect on nitrotyrosine distribution or content. (3) The nitrotyrosine of both mucosal proteins and the muscle protein are increased in the 1 week obstructed bladder; whereas, only the 62 kD signal is increased in the two week obstructed bladder mucosa. (4) The contractile response to FS are reduced to a significantly greater degree than the responses to carbachol, KCl, or ATP. Conclusions: These studies clearly demonstrated that partial outlet obstruction in rabbits results in significant increases in nitrotyrosine within the bladder and may contribute to the contractile dysfunctions mediated by partial outlet obstruction. (Mol Cell Biochem 276: 143–148, 2005)  相似文献   
29.
New 2-substituted-phenyl-1H-benzimidazole-5-carboxylic acids (35, 38), ethyl-5-carboxylate (36), -5-carboxamides (37, 39),-5-carboxaldehyde (42), -5-chloro (40), -5-trifluoromethyl (41), and -5-carbonitriles (44-53, 55-67), -6-carbonitrile (54) were prepared and evaluated in vitro against Candida species. The cyano substituted compounds 53, 57, 58 and 61 exhibited the greatest activity with MIC values of 3.12 microg/mL, values similar to that of fluconazole.  相似文献   
30.
Anaerobic ammonium oxidation is a recent addition to the microbial nitrogen cycle, and its metabolic pathway, including the production and conversion of its intermediate hydrazine, is not well understood. Therefore, the effect of hydroxylamine addition on the hydrazine metabolism of anaerobic ammonium-oxidizing (anammox) bacteria was studied both experimentally and by mathematical modeling. It was observed that hydroxylamine was disproportionated biologically in the absence of nitrite into dinitrogen gas and ammonium. Little hydrazine accumulated during this process; however, rapid hydrazine production was observed when nearly all hydroxylamine was consumed. A mechanistic model is proposed in which hydrazine is suggested to be continuously produced from ammonium and hydroxylamine (possibly via nitric oxide) and subsequently oxidized to N(2). The electron acceptor for hydrazine oxidation is hydroxylamine, which is reduced to ammonium. A decrease in the hydroxylamine reduction rate, therefore, leads to a decrease in the hydrazine oxidation rate, resulting in the observed hydrazine accumulation. The proposed mechanism was verified by a mathematical model which could explain and predict most of the experimental data.  相似文献   
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