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1.
Anionic peroxidase isoenzymes, separated on acrylamide gels, were examined in two flax genotrophs and in their reciprocal F2 hybrids. Isoenzyme 1 exhibited a significant difference in Rm between stem base and apex and there was a gradient of decreasing Rm and activity between base and apex. Isoenzyme 2 displayed only the activity gradient. The parents differed significantly in the Rm's and activities of isoenzymes 1 and 2, and the F2's showed complete dominance of the L parent for Rm, with activities being approximately intermediate. 相似文献
2.
Reciprocal and nonreciprocal recombination at the glucocerebrosidase gene region: implications for complexity in Gaucher disease 下载免费PDF全文
Tayebi N Stubblefield BK Park JK Orvisky E Walker JM LaMarca ME Sidransky E 《American journal of human genetics》2003,72(3):519-534
Gaucher disease results from an autosomal recessive deficiency of the lysosomal enzyme glucocerebrosidase. The glucocerebrosidase gene is located in a gene-rich region of 1q21 that contains six genes and two pseudogenes within 75 kb. The presence of contiguous, highly homologous pseudogenes for both glucocerebrosidase and metaxin at the locus increases the likelihood of DNA rearrangements in this region. These recombinations can complicate genotyping in patients with Gaucher disease and contribute to the difficulty in interpreting genotype-phenotype correlations in this disorder. In the present study, DNA samples from 240 patients with Gaucher disease were examined using several complementary approaches to identify and characterize recombinant alleles, including direct sequencing, long-template polymerase chain reaction, polymorphic microsatellite repeats, and Southern blots. Among the 480 alleles studied, 59 recombinant alleles were identified, including 34 gene conversions, 18 fusions, and 7 downstream duplications. Twenty-two percent of the patients evaluated had at least one recombinant allele. Twenty-six recombinant alleles were found among 310 alleles from patients with type 1 disease, 18 among 74 alleles from patients with type 2 disease, and 15 among 96 alleles from patients with type 3 disease. Several patients carried two recombinations or mutations on the same allele. Generally, alleles resulting from nonreciprocal recombination (gene conversion) could be distinguished from those arising by reciprocal recombination (crossover and exchange), and the length of the converted sequence was determined. Homozygosity for a recombinant allele was associated with early lethality. Ten different sites of crossover and a shared pentamer motif sequence (CACCA) that could be a hotspot for recombination were identified. These findings contribute to a better understanding of genotype-phenotype relationships in Gaucher disease and may provide insights into the mechanisms of DNA rearrangement in other disorders. 相似文献
3.
Vasiliu D Razi N Zhang Y Jacobsen N Allin K Liu X Hoffmann J Bohorov O Blixt O 《Carbohydrate research》2006,341(10):1447-1457
Poly-N-acetyllactosamines (pLNs) are common terminal sugars of many N- and O-linked glycan structures present in glycoproteins and glycolipids. Utilizing various glycosyltransferases, we developed new and efficient chemoenzymatic methods for the synthesis of pLNs in gram-scale. Specifically, the use of sialyltransferases and fucosyltransferases enabled us to synthesize and purify 24 blood group and tumor-associated pLN derivatives with alpha-(2-->3)- and alpha-(2-->6)-linked sialic acid, as well as with alpha-(1-->2)- and alpha-(1-->3)-linked fucose. All synthesized derivatives were linked to a short 2-azidoethyl spacer for further modification. 相似文献
4.
Bahmani Bahareh Amini-bayat Zahra Ranjbar Mohammad Mehdi Bakhtiari Nahid Zarnani Amir-Hassan 《International journal of peptide research and therapeutics》2021,27(1):365-378
International Journal of Peptide Research and Therapeutics - Cervical cancer is the second most common leading cause of women's death due to cancer worldwide, about 528,000 patients’... 相似文献
5.
Vibrio cholerae Evades Neutrophil Extracellular Traps by the Activity of Two Extracellular Nucleases
Andrea Seper Ava Hosseinzadeh Gregor Gorkiewicz Sabine Lichtenegger Sandro Roier Deborah R. Leitner Marc R?hm Andreas Grutsch Joachim Reidl Constantin F. Urban Stefan Schild 《PLoS pathogens》2013,9(9)
The Gram negative bacterium Vibrio cholerae is the causative agent of the secretory diarrheal disease cholera, which has traditionally been classified as a noninflammatory disease. However, several recent reports suggest that a V. cholerae infection induces an inflammatory response in the gastrointestinal tract indicated by recruitment of innate immune cells and increase of inflammatory cytokines. In this study, we describe a colonization defect of a double extracellular nuclease V. cholerae mutant in immunocompetent mice, which is not evident in neutropenic mice. Intrigued by this observation, we investigated the impact of neutrophils, as a central part of the innate immune system, on the pathogen V. cholerae in more detail. Our results demonstrate that V. cholerae induces formation of neutrophil extracellular traps (NETs) upon contact with neutrophils, while V. cholerae in return induces the two extracellular nucleases upon presence of NETs. We show that the V. cholerae wild type rapidly degrades the DNA component of the NETs by the combined activity of the two extracellular nucleases Dns and Xds. In contrast, NETs exhibit prolonged stability in presence of the double nuclease mutant. Finally, we demonstrate that Dns and Xds mediate evasion of V. cholerae from NETs and lower the susceptibility for extracellular killing in the presence of NETs. This report provides a first comprehensive characterization of the interplay between neutrophils and V. cholerae along with new evidence that the innate immune response impacts the colonization of V. cholerae in vivo. A limitation of this study is an inability for technical and physiological reasons to visualize intact NETs in the intestinal lumen of infected mice, but we can hypothesize that extracellular nuclease production by V. cholerae may enhance survival fitness of the pathogen through NET degradation. 相似文献
6.
Application of Bacillus pumilus as a potential biocontrol agent of Fusarium wilt of tomato 总被引:1,自引:0,他引:1
Nahid Heidarzadeh Sareh Baghaee-Ravari 《Archives Of Phytopathology And Plant Protection》2013,46(13-16):841-849
The current study aimed at evaluating the possibility of native Bacillus pumilus species to control Fusarium wilt in tomato and examine its effect on plant growth. Biocontrol traits of B. pumilus strains, biofilm assay, root colonisation and in vivo studies under pot conditions were determined. Strain ToIrMA-KC806242 formed biofilm efficiently and could colonise and survive on tomato rhizosphere (3.1 × 104 CFU/g of root). The amount of auxin production was recorded 29.7 μg/ml at the 96th hour of incubation. Siderophore production was determined positive, while ToIrMA was not able to solubilise phosphate compounds or produce cyanide hydrogen. Statistical analysis of data revealed that the increase in root and shoot length was recorded 60 and 84%, respectively, over control. In addition, about 73% reduction in disease incidence was determined in vivo experiments. In conclusion, this study suggests B. pumilus ToIrMA strain as a possible biocontrol agent in the field experiments. 相似文献
7.
Measurement of some Benzylisoquinoline Alkaloids in Different Organs of Persian Poppy during Ontogenetical Stages 下载免费PDF全文
Mahdi Rezaei Mohammad Reza Naghavi Abdol Hadi Hosseinzadeh Alireza Abbasi 《化学与生物多样性》2016,13(5):539-543
Papaver bracteatum, a perennial species, has been known as a rich source of thebaine and a potential alternative to Papaver somniferum for the production of codeine and some semisynthetic antagonist drugs. In this study, ion mobility spectrum (IMS) of the root, leaf, bottom part of stem, upper part of stem, capsule wall, petal, and capsule content during developmental stages of P. bracteatum including annual rosette, perennial rosette, bud initiation, pendulous bud, preflowering, and lancing were investigated. The IMS revealed thebaine, papaverine, and noscapine as the major components of the extracted alkaloids. Based on the results of the study it appears that, at least in part, there is a competition among the biosynthesis pathways of papaverine, noscapine, and morphinan alkaloids from a common source . Root and capsule wall were the most potent organs for extraction of thebaine, while lancing stage was the best developmental stage for thebaine exploitation. However, it seems that total biomass of root and capsule wall plays a key role in the final selection of favorite organ. Although papaverine and noscapine in the stem at preflowering stage had the most quantity, significant amounts were found in the capsule wall. In general, total alkaloid content of leaf was lower than the other plant parts. 相似文献
8.
Jamal S.M. Sabir Abdelfatteh El Omri Noor A. Shaik Babajan Banaganapalli Nahid H. Hajrah Houda Zrelli Leila Arfaoui Zuhier A. Awan Abdulkader M. Shaikh Omar Arif Mohammed Mona G. Alharbi Alawiah M. Alhebshi Robert K. Jansen Muhummadh Khan 《Saudi Journal of Biological Sciences》2019,26(7):1338-1343
Obesity is a multifactorial metabolic disorder characterized by low grade chronic inflammation. Rare and novel mutations in genes which are vital in several key pathways have been reported to alter the energy expenditure which regulates body weight. The TP53 or p53 gene plays a prominent role in regulating various metabolic activities such as glycolysis, lipolysis, and glycogen synthesis. Recent genome-wide association studies reported that tumor suppressor gene p53 variants play a critical role in the predisposition of type 2 diabetes and obesity. Till date, no reports are available from the Arabian population; hence the present study was intended to assess the association between p53 variants with risk of obesity development in the Saudi population. We have selected three p53 polymorphisms, rs1642785 (C > G), and rs9894946 (A > G), and rs1042522 (Pro72Arg; C > G) and assessed their association with obesity risk in the Saudi population. Phenotypic and biochemical parameters were also evaluated to check their association with p53 genotypes and obesity. Genotyping was carried out on 136 obese and 122 normal samples. We observed that there is significantly increased prevalence p52 Pro72Arg (rs1042522) polymorphism in obese persons when compared to controls at GG genotype in overall comparison (OR: 2.169, 95% CI: 1.086-4.334, p = 0.02716). Male obese subjects showed three-fold higher risk at GG genotype (OR: 3.275, 95% CI: 1.230-8.716, p = 0.01560) and two-fold risk at G allele (OR: 1.827, 95% CI: 1.128-2.958, p = 0.01388) of p53 variant Pro72Arg respectively. This variant has also shown significant influence on cholesterol, LDL level, and random insulin levels in obese subjects (p ≤ 0.05). In conclusion, p53 Pro72Arg variant is highly prevalent among obese individuals and may act as a genetic modifier for obesity development among Saudis. 相似文献
9.
10.
Elaheh Esmaeili Masoud Soleimani Mohammad Adel Ghiass Shadie Hatamie Saeed Vakilian Mahsa Soufi Zomorrod Negar Sadeghzadeh Manouchehr Vossoughi Simzar Hosseinzadeh 《Journal of cellular physiology》2019,234(8):13617-13628
While the differentiation factors have been widely used to differentiate mesenchymal stem cells (MSCs) into various cell types, they can cause harm at the same time. Therefore, it is beneficial to propose methods to differentiate MSCs without factors. Herein, magnetoelectric (ME) nanofibers were synthesized as the scaffold for the growth of MSCs and their differentiation into neural cells without factors. This nanocomposite takes the advantage of the synergies of the magnetostrictive filler, CoFe2O 4 nanoparticles (CFO), and piezoelectric polymer, polyvinylidene difluoride (PVDF). Graphene oxide nanosheets were decorated with CFO nanoparticles for a proper dispersion in the polymer through a hydrothermal process. After that, the piezoelectric PVDF polymer, which contained the magnetic nanoparticles, underwent the electrospun process to form ME nanofibers, the ME property of which has the potential to be used in areas such as tissue engineering, biosensors, and actuators. 相似文献