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1.
Functional studies have suggested the important role of early growth response 1 (EGR1) and Laminin α2-chain (LAMA2) in human eye development. Genetic studies have reported a significant association of the single nucleotide polymorphism (SNP) in the LAMA2 gene with myopia. This study aimed to evaluate the association of the tagging SNPs (tSNPs) in the EGR1 and LAMA2 genes with high myopia in two independent Han Chinese populations. Four tSNPs (rs11743810 in the EGR1 gene; rs2571575, rs9321170, and rs1889891 in the LAMA2 gene) were selected, according to the HapMap database (http://hapmap.ncbi.nlm.nih.gov), and were genotyped using the ligase detection reaction (LDR) approach for 167 Han Chinese nuclear families with extremely highly myopic offspring (<?10.0 diopters) and an independent group with 485 extremely highly myopic cases (<?10.0 diopters) and 499 controls. Direct sequencing was used to confirm the LDR results in twenty randomly selected subjects. Family-based association analysis was performed using the family-based association test (FBAT) software package (Version 1.5.5). Population-based association analysis was performed using the Chi-square test. The association analysis power was estimated using online software (http://design.cs.ucla.edu). The FBAT demonstrated that all four tSNPs tested did not show association with high myopia (P>0.05). Haplotype analysis of tSNPs in the LAMA2 genes also did not show a significant association (P>0.05). Meanwhile, population-based association analysis also showed no significant association results with high myopia (P>0.05). On the basis of our family- and population-based analyses for the Han Chinese population, we did not find positive association signals of the four SNPs in the LAMA2 and EGR1 genes with high myopia.  相似文献   

2.
Phytophthora capsici is a phytopathogen that causes a destructive pepper blight that is extremely difficult to control. Using a fungicide application against the disease is costly and relatively ineffective and there is also a huge environmental concern about the use of such chemicals. The genus Trichoderma has been known to have a potential biocontrol issue. In this paper we investigate the mechanism for causing the infection of T. asperellum against P. capsici. Trichoderma sp. (isolate CGMCC 6422) was developed to have a strong antagonistic action against hyphae of P. capsici through screening tests. The strain was identified as T. asperellum through using a combination of morphological characteristics and molecular data. T. asperellum was able to collapse the mycelium of the colonies of the pathogen through dual culture tests by breaking down the pathogenic hyphae into fragments. The scanning electron microscope showed that the hyphae of T. asperellum surrounded and penetrated the pathogens hyphae, resulting in hyphal collapse. The results show that seven days after inoculation, the hyphae of the pathogen were completely degraded in a dual culture. T. asperellum was also able to enter the P. capsici oospores through using oogonia and then developed hyphae and produced conidia, leading to the disintegration of the oogonia and oospores. Seven days after inoculation, an average 10.8% of the oospores were infected, but at this stage, the structures of oospores were still intact. Subsequently, the number of infected oospores increased and the oospores started to collapse. Forty-two days after inoculation, almost all the oospores were infected, with 9.3% of the structures of the oospores being intact and 90.7% of the oospores having collapsed.  相似文献   

3.
Breast cancer is one of the leading causes of death in women today. Some of the patients are hereditary, with a large proportion characterized by mutation in BRCA1 and/or BRCA2 genes. In this review, we provide an overview of these two genes, focusing on their relationship with hereditary breast cancers. BRCA1/2 associated hereditary breast cancers have unique features that differ from the general breast cancers, including alterations in cellular molecules, pathological bases, biological behavior, and a different prevention strategy. But the outcome of BRCA1/2 associated hereditary breast cancers still remains controversial; further studies are needed to elucidate the nature of BRCA1/2 associated hereditary breast cancers. Project supported by the National Natural Science Foundation of China (No. 30772510) and the Joint Program of Ministry of Health and Zhejiang Provincal Government of China (No. WKJ2006-2-008)  相似文献   

4.
The AtTOM1 gene ofArabidopsis thaliana had been shown to be essential for the efficient multiplication of Tobacco mosaic virus (TMV) in A. thaliana. In this study, we cloned an AtTOM1-like gene from Nicotiana benthamiana named as NbTOM1. Sequence alignment showed that NbTOM1 is closely related to AtTOM1 homologues of N. tabacum and Lycopersicon esculentum with 97.2% and 92.6% nucleotide sequence identities, respectively. Silencing of NbTOM1 by a modified viral satellite DNA-based vector resulted in complete inhibition of the multiplication of TMV in N. benthamiana. The result suggests that inhibition of NbTOM1 via RNA silencing is a potentially useful method for generating TMV-resistant plants.  相似文献   

5.
The insulin-like growth factor 1 (IGF1) gene is a member of the group of somatotropin axis genes that play a significant role in cell proliferation and growth of muscles. Here, we searched for polymorphisms in buffalo IGF1 and found two novel single nucleotide polymorphisms (SNPs), G64A and G280A, in the noncoding sequences of exon 1 and exon 4, respectively. Statistical analysis of different genotypes showed that the individuals with GG genotypes had significantly (P<0.05) higher body weight (BW) and average daily gain (ADG) than those with other genotypes at ages of 3–6 months in G64A SNP and 6–9 months in G280A SNP. The combined genotypes of these two SNPs produced three haplotypes, GG/GG, AG/AG, and AA/AA, which were significantly associated (P<0.0001) with BW and ADG at an age from 3 to 12 months. Buffaloes with the homozygous GG/GG haplotype showed higher growth performance than other buffaloes. The two SNPs were correlated with mRNA levels of IGF1 and IGF1 receptor (IGF1R) in semitendinosus muscle as well as with the serum concentration level of IGF1. Also, buffaloes with GG/GG haplotype showed higher mRNA and serum concentration levels. The data revealed that these two SNPs could be valuable genetic markers for selection of Egyptian buffaloes for better performance in the population.  相似文献   

6.
7.
The Bacillus strain BH072 isolated from a honey sample showed strong antifungal activity against phytopathogen. Gene cloning test demonstrated that the strain had a tasA gene encoding an antifungal TasA protein. Although the wild strain simultaneously produced various antifungal substances, only the physicochemical property and antifungal activity of TasA protein were unclear due to the difficulty in extraction. In this study, tasA gene encoding the protein from Bacillus sp. BH072 was amplified by using the polymerase chain reaction (PCR) method and cloned into pET 28a (+) vector, and then expressed in host cells Escherichia coli BL21 (DE3). The expressed proteins were collected by centrifugation and ultrasonic treatment, and then purified by using nickel-nitrilotriacetic acid (Ni-NTA) metal affinity column and dialysis methods. The result of sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test showed that an expected protein band appeared with a size of 31 kDa. The expressed products possessed antifungal activity against the phytopathogenic indicator strain Botrytis cinerea. A genetically engineered strain tasA of E. coli was established in this study which can efficiently express Tas A protein.  相似文献   

8.
9.
Two-component genes are kinds of genetic elements involved in regulation of antibiotic production inStreptomyces coelicolor. DNA microarray analysis revealed thatecrA1/A2, which mapped at distant sites fromred lucus and encode respectively the kinase and regulator, expressed coordinately with genes of Red specific biosynthetic pathway.ecrA1 andecrA2 gene-disruptive mutants were constructed using homogenotisation by reciprocal double crossover. Fermentation data showed that the undecylprodigiosin (Red) level of production was lower than that of wild-type strain. However, the change of the actinorhodin (Act) production level was not significant compared with wild type. Thus, these experiment results confirmed that the two-component systemecrA1/A2 was positive regulatory element forred gene cluster. Project (No.20172046) supported by the National Natural Foundation of China  相似文献   

10.
R. Jayaraman 《Resonance》2008,13(10):898-908
One of the goals of genetics is to understand genes in as much detail as possible. For instance, with respect to a given gene, one would like to know its chromosomal location, its physical and genetic size, its neighbours, the number of mutations/alleles defining the gene, the order of mutations, the genetic/physical distance between them, etc. Thus, rather than focusing on the whole genome, one focuses on the finer details of a given genetic segment. The exercise of probing such details is called ‘fine structure genetic analysis’. There are several pioneers who have contributed enormously to this area in many bacterial and phage systems. Two stalwarts, Seymour Benzer and Charles Yanofsky, stand preeminent among them. In the following pages I present briefly Benzer’s outstanding work on the fine structure of the rII region of bacteriopage T4. These path-breaking studies contributed significantly to our understanding of the structure, organization and function of genes. R Jayaraman is an Emeritus Professor of Molecular Biology at the School of Biological Sciences, Madurai Kamaraj University, Madurai, where he taught and carried out research in the area of microbial genetics for three decades.  相似文献   

11.
In the present work, the fruits of four Morus species, namely Morus alba (white mulberry), Morus nigra (black mulberry), Morus laevigata (large white fruit), and Morus laevigata (large black fruit), were analyzed for proximate composition, essential minerals, and antioxidant potentials. For this purpose, the ripe fruits were collected from the northern regions of Pakistan. The major nutritional components (moisture, ash, lipids, proteins, fibres, carbohydrates, and total sugar) were found to be in the suitable range along with good computed energy. Total dry weight, pH, and titratable acidity (percent citric acid) were (17.60±1.94)–(21.97±2.34) mg/100 g, (3.20±0.07)–(4.78±0.15), and (0.84±0.40)%–(2.00±0.08)%, respectively. Low riboflavin (vitamin B2) and niacin (vitamin B3) contents were recorded in all the fruits, while ascorbic acid (vitamin C) was in the range from (15.20±1.25) to (17.03±1.71) mg/100 g fresh weight (FW). The mulberry fruits were rich with regard to the total phenol and alkaloid contents, having values of (880±7.20)–(1650±12.25) mg/100 g FW and (390±3.22)–(660±5.25) mg/100 g FW, respectively. Sufficient quantities of essential macro-(K, Ca, Mg, and Na) and micro-(Fe, Zn, and Ni) elements were found in all the fruits. K was the predominant element with concentration ranging from (1270±9.36) to (1731±11.50) mg/100 g, while Ca, Na, and Mg contents were (440±3.21)–(576±7.37), (260±3.86)–(280±3.50), and (240±3.51)–(360±4.20) mg/100 g, respectivly. The decreasing order of micro-minerals was Fe>Zn>Ni. The radical scavenging activity of methanolic extract of fruits was concentration-dependent and showed a correlation with total phenolic constituents of the respective fruits. Based on the results obtained, mulberry fruits were found to serve as a potential source of food diet and natural antioxidants.  相似文献   

12.
This paper proposes a new approach for multi-objective robust control. The approach extends the standard generalizedl 2 (Gl 2) and generalizedH 2 (GH 2) conditions to a set of new linear matrix inequality (LMI) constraints based on a new stability condition. A technique for variable parameterization is introduced to the multi-objective control problem to preserve the linearity of the synthesis variables. Consequently, the multi-channel multi-objective mixed Gl 2/GH 2 control problem can be solved less conservatively using computationally tractable algorithms developed in the paper. Project supported by the National Natural Science Foundation of China (No. 60374028), and the Scientific Research Foundation for Returned Overseas Chinese Scholars, Ministry of Education (No. [2004]176)  相似文献   

13.
The aim of this study is to assess the antibacterial and anti-biofilm properties of the lipid extract from Mantidis ootheca against the gentamycin resistant Pseudomonas aeruginosa. The chemical composition of the lipid extract and its relative proportion were determined using the technique of gas chromatography coupled with mass spectrometry (GC-MS). Antibacterial susceptibility tests were performed using a disc diffusion assay and the minimum inhibition concentration (MIC) was determined by way of the agar dilution method. The anti-biofilm test was carried out with crystal violet staining and scanning electron microscopy (SEM). There were 16 compounds detected, and the most abundant components were sesquiterpenoids, monoterpenes, and trace aromatic compounds. The MIC for P. aeruginosa was 4 mg/ml and the eradication effect on preformed biofilms was established and compared with a ciprofloxacin control. The results of our study indicated that a lipid extract from M. ootheca could be used as a topical and antibacterial agent with anti-biofilm activity in the future.  相似文献   

14.
The endangered medicinal herb,Changium smyrnioides can only be found in deciduous forest gaps within the middle to northern subtropical broad-leaved evergreen forest zone of China. The considerable plasticity of its shoot and root structure helps it to capture light more effectively in winter and early spring, and to adapt to the soil moisture conditions in its narrow habitat. Another medicinal plant,Anthriscus sylvestris, is of similar economic importance but commonly distributed widely. In contrast toC. smyrnioides, it has low structural plasticity. It is also specialized to adapt to the moist and sunny environment, where habitat, such as the banks of creeks and rivers, is abundant. Project supported by the National Basic Research Program (973) of China (No. G2000046805) and the National Natural Science Foundation of China (No. 39970058)  相似文献   

15.
Embryogenic calli were induced from the seeds of creeping bentgrass (Agrostis palustris Huds.) cv. Regent and colonial bentgrass (Agrostis Tenuis Sibth. Fl. Oxen.) cv. Tiger. The embryogenic calli were precultured on fresh medium for 4–7 days and then co-cultivated withAgrobacterium tumefaciens, LBA4404. which contains plasmid vector-pSBGM harboring bar coding region, synthetic green fluorescent protein (sGFP) coding region and matrix attachment region (MAR). After 3 days of co-cultivation, the calli were washed thoroughly and transferred to MS medium containing 2 mg/L of 2, 4-D, 12–15 mg/L phosphinothricin (PPT) and 250 mg/L of cefotaxime. After 2–3 months of selection, the actively growing calli of ‘Regent’ and ‘Tiger’ were transferred to MS medium with 12–15 mg/L PPT and 250 mg/L cefotazime for regeneration. The putative transformants were maintained on MS medium with 3 mg/L PPT for long period but control died within 1 month. After establishing in greenhouse, the transformants also showed strong resistance to 0.4% of herbicide Basta but control plants died within 2 weeks. Under confocal microscope, both young leaves and roots showed significant GFP expression. PCR analysis revealed the presence of a DNA fragment of GFP gene at the expected size (380 bp) in the transformants and its absence in a randomly selected control plant.  相似文献   

16.
17.
The inhibitory effects of Lactobacillus plantarum-fermented and non-fermented Inula britannica extracts on the tyrosinase activity were comparatively investigated to examine whether and how they improve the whitening activity, and the contents of total flavonoids and polyphenolics as bioactive compounds were determined. The skin whitening activity using in vitro or ex vivo tyrosinase and L-3,4-dihydroxyphenylalanine (L-DOPA) staining was examined. The total flavonoid content (TFC) was increased by 13.4% after 72 h-fermentation. The viabilities of the B16F10 cells treated with the fermented and non-fermented control extracts were 100.26% and 92.15% at 500 μg/ml, respectively. In addition, the inhibition of tyrosinase activity was increased by the fermented samples from 29.33% to 41.74% following fermentation for up to 72 h. The tyrosinase activity of the untreated control group was increased to 145.69% in B16F10 cells. The results showed that I. britannica fermented by L. plantarum dose-dependently inhibited tyrosinase activity, which was stimulated by α-melanocyte stimulating hormone. These results suggest that lactic fermented I. britannica extracts can be used as effective skin-whitening materials.  相似文献   

18.
This key paper is intended to produce a comparison of Bildung and globalization, acknowledging that Bildung and globalization are both fuzzy concepts. Our comparison of globalization and Bildung therefore is to be seen as a construction. To reach this objective, we start with the identification of dimensions of the concept of globalization based predominantly on sociological research. This analysis is followed by explication of dimensions of the concept of Bildung as they can be identified before a frame of globalization. We want to find out whether it makes sense to see globalization as one part of a new model of Bildung. In the conclusion, we demonstrate the normativity of each and any theory of Bildung in globalizing times, and we explain why it is necessary to reflect on the normativity of the different concepts. We indicate where we see connections with the other papers of this special issue of “Zeitschrift für Erziehungswissenschaft”.  相似文献   

19.
Objective: To investigate the distribution ofH. pylori antigens in the gastric mucosa in patients withH. pylori infection, and the relationship between the distribution and gastric cancer. Methods: Of 112 patients confirmed by pathological study to have chronic superficial gastritis, precancerous changes (chronic atrophic gastritis, intestinal metaplasia or atypical hyperplasia) and gastric cancer, 28 wereH. pylori negative and 84 wereH. pylori positive.H. pylori antigens in the gastric mucosa were detected by immunohistochemistry. Results: TheH. pylori positive group, comprised 12 of 22 (50.0%) in the chronic superficial gastritis group, 22 of 25 (88.0%) in the precancerous changes group and 13 of 35 (37.1%) in the gastric cancer group. The positive rates ofH. pylori antigens in the cytoplasm progressively increased, respectively at 0.0% (0/12), 63.6% (14/22) and 84.6% (11/13) for the same groups (χ 2=19.76,P=0.000);H. pylori antigens were located in the mucus layer and above the neck of the mucosal gland in 9 of 12 (75.0%) cases with chronic superficial gastritis, at the neck of the mucosal gland and the isthmus in 12 of 22 (54.5%) cases with precancerous changes, below the isthmus in 9 of 13 (69.2%) cases with gastric cancer (χ 2=25.30,P=0.000). In theH. pylori negative group, noH. pylori antigen was observed. Conclusion: With the progression of chronic superficial gastritis→precancerous changes→gastric cancer,H. pylori antigens progressively migrated from the outer part to the inner part of the cell, and from the superficial to the deep gastric mucosa.  相似文献   

20.
(R)-2-hydroxy-3-phenylpropionic acid (PLA) is an ideal antimicrobial compound with broad-spectrum activity against a wide range of Gram-positive bacteria, some Gram-negative bacteria, and fungi. We studied the bioconversion of phenylpyruvate (PPA) to PLA using whole recombinant Escherichia coli cells in a series of buffer/organic solvent systems. Octane was found to be the best organic solvent. The optimum volume ratio of the water phase to the n-octane phase, conversion temperature, substrate concentration, and cell concentration were 6:4, 40 °C, 12.5 g/L, and 30 g/L wet cells, respectively. Under the optimized conditions, the average PLA productivity in the aqueous/n-octane system was 30.69% higher than that in the aqueous system, and 32.31 g/L PLA was obtained with the use of a stirred reactor (2-L scale). Taken together, our findings indicated that PLA biosynthesis was more efficient in an aqueous/n-octane biphasic system than in a monophasic aqueous system. The proposed biphasic system is an effective strategy for enhancing PLA yield and the biosynthesis of its analogues.  相似文献   

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