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51.
Lizette Auezova Fadia Najjar Olga Selivanova Elie Hajj Moussa Mona Diab Assaf 《Journal of applied phycology》2013,25(4):1189-1196
The present study aims to investigate the levels of polyphenols and antioxidant activity in one of the most important commercial species of seaweeds in Kamchatka, an edible brown seaweed Saccharina bongardiana. Six extracts of S. bongardiana, acetone, methanol, ethanol, and the respective 70 % aqueous solutions, were assessed for total phenol content in order to determine the most efficient extracting solvent. The total phenol content was measured by the Folin–Ciocalteu method and expressed as phloroglucinol equivalents (PGE). The antioxidant tests used were 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging assay, linoleic acid-β carotene oxidation inhibiting assay, and Fe2+ ion chelating method. Higher phenolic contents were obtained using aqueous organic solvents, as compared to the respective absolute solvents; 70 % acetone was found to be the most efficient solvent (1.039 mg PGE 100 mg?1 dry algal powder). High significant correlations were noted between total phenol content and the tested antioxidant activities; so the aqueous organic extracts exhibited the highest antioxidant activities versus DPPH radicals (EC50 values of 0.6–1.1 mg dry weight (DW) mL?1), linoleic acid-β carotene oxidation (74–78 % at 0.8 mg DW mL?1), as well as ferrous ions (EC50 values of 5.0–7.9 mg DW mL?1). Some methodological recommendations regarding the assays used and the expression of results are proposed. 相似文献
52.
Soheir M. El Nahas Mona A. Bibars Dalia A. Taha Hassan I. El-Sayyad 《Journal of Genetic Engineering and Biotechnology》2013,11(1):75-77
The present study investigates CSN1S1 casein gene polymorphism in Egyptian buffalo. CSN1S1 was analyzed in 17 unrelated Egyptian lactating buffalo. The amplified segment includes the last 43 amino acids of Exon 17 and part of Intron 17. In the present study we report for the first time the presence of 2 variants 178Ser (TCA) and 178Leu (TTA) in Egyptian buffalo CSN1S1 gene. The genotypic frequencies in the investigated Egyptian buffalo sample were 0.47, 0.058 and 0.47 for homozygous 178Ser, for homozygous 178Leu and heterozygous 178Leu/Ser, respectively. The 178Ser and 178Leu variant frequencies are 0.64 and 0.36, respectively which indicates the superiority of variant 178Ser in Egyptian buffalo. The allelic frequency in Egyptian buffalo is not much different from the corresponding allelic frequency in Italian buffalo (0.69 and 0.31 for 178Ser and 178Leu, respectively) as reported by Chianese et al. [3]. This is not surprising since they both belong to Mediterranean type. 相似文献
53.
Wafaa M. Ezzat Yasser A. Elhosary Nour A. Abdulla Hala M. Raslan Omneya M. Saleh Mona H. Ibrahim Maha A. Rasheed H. El-Hariri 《Journal of Genetic Engineering and Biotechnology》2013,11(1):69-73
BackgroundStudies revealed that insulin resistance is associated with fibrosis progression and has negative impact on sustained virological response after standard antiviral therapy in patients with chronic hepatitis C (CHC).AimTo assess the role of IR on progression of liver fibrosis and early virological response (EVR) rates in patients with chronic hepatitis C infection.Patients and methodsThe study population comprised 79 subjects who underwent combination therapy for CHC. Laboratory investigations in the form of glucose, insulin, bilirubin, alanine aminotransferase (ALT), cholesterol and triglycerides and liver biopsy were done for all patients. Insulin resistance was calculated using the homeostasis model of IR (HOMA-IR).ResultsIR was increased (>2 IU) in 31 (40.7%) of patients. Early virological response was achieved among 37 patients (48.7%). No difference in EVR, viral load or grade of liver fibrosis between patients with and without IR. A significant positive correlation was found between IR and liver steatosis.ConclusionInsulin resistance is a common finding in CHC, it is associated with increase liver steatosis. However it has no impact on EVR to combined interferon ribavirin therapy, viral load or necroinflammation. 相似文献
54.
Purpose
A recent large genome-wide association study (GWAS) identified multiple variants associated with primary angle-closure glaucoma (PACG). The present study investigated the role of these variants in two cohorts with PACG recruited from Australia and Nepal.Method
Patients with PACG and appropriate controls were recruited from eye clinics in Australia (n = 232 cases and n = 288 controls) and Nepal (n = 106 cases and 204 controls). Single nucleotide polymorphisms (SNPs) rs3753841 (COL11A1), rs1015213 (located between PCMTD1 and ST18), rs11024102 (PLEKHA7), and rs3788317 (TXNRD2) were selected and genotyped on the Sequenom. Analyses were conducted using PLINK and METAL.Results
After adjustment for age and sex, SNP rs3753841 was found to be significantly associated with PACG in the Australian cohort (p = 0.017; OR = 1.34). SNPs rs1015213 (p = 0.014; OR 2.35) and rs11024102 (p = 0.039; OR 1.43) were significantly associated with the disease development in the Nepalese cohort. None of these SNPs survived Bonferroni correction (p = 0.05/4 = 0.013). However, in the combined analysis, of both cohorts, rs3753841 and rs1015213 showed significant association with p-values of 0.009 and 0.004, respectively both surviving Bonferroni correction. SNP rs11024102 showed suggestive association with PACG (p-value 0.035) and no association was found with rs3788317.Conclusion
The present results support the initial GWAS findings, and confirm the SNP’s contribution to PACG. This is the first study to investigate these loci in both Australian Caucasian and Nepalese populations. 相似文献55.
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59.
Mona Gazel Kadriye Çağlayan Hüseyin Başpınar Juan F. Mejia Samanta Paltrinieri Assunta Bertaccini Nicoletta Contaldo 《Journal of Phytopathology》2016,164(2):136-140
Symptoms resembling those associated with phytoplasma presence were observed in pomegranate (Punica granatum L.) trees in June 2012 in the Aegean Region of Turkey (Ayd?n province). The trees exhibiting yellowing, reduced vigour, deformations and reddening of the leaves and die‐back symptoms were analysed to verify phytoplasma presence. Total nucleic acids were extracted from fresh leaf midribs and phloem tissue from young branches of ten symptomatic and five asymptomatic plants. Nested polymerase chain reaction assays using universal phytoplasma‐specific 16S rRNA and tuf gene primers were performed. Amplicons were digested with Tru1I, Tsp509I and HhaI restriction enzymes, according to the primer pair employed. The phytoplasma profiles were identical to each other and to aster yellows (16SrI‐B) strain when digestion was carried out on 16Sr(I)F1/R1 amplicons. However, one of the samples showed mixed profiles indicating that 16SrI‐B and 16SrXII‐A phytoplasmas were present when M1/M2 amplicons were digested, the reamplification of this sample with tuf cocktail primers allowed to verify the presence of a 16SrXII‐A profile. One pomegranate aster yellows strain AY‐PG from 16S rRNA gene and the 16SrXII‐A amplicon from tuf gene designed strain STOL‐PG were directly sequenced and deposited in GenBank under the Accession Numbers KJ818293 and KP161063, respectively. To our knowledge, this is the first report of 16SrI‐B and 16SrXII‐A phytoplasmas in pomegranate trees. 相似文献
60.
Wheat and barley are two of the founder crops of the agricultural revolution that took place 10,000 years ago in the Fertile Crescent and both crops remain among the world's most important crops. Domestication of these crops from their wild ancestors required the evolution of traits useful to humans, rather than survival in their natural environment. Of these traits, grain retention and threshability, yield improvement, changes to photoperiod sensitivity and nutritional value are most pronounced between wild and domesticated forms. Knowledge about the geographical origins of these crops and the genes responsible for domestication traits largely pre-dates the era of nextgeneration sequencing, although sequencing will lead to new insights. Molecular markers were initially used to calculate distance(relatedness), genetic diversity and to generate genetic maps which were useful in cloning major domestication genes. Both crops are characterized by large,complex genomes which were long thought to be beyond the scope of whole-genome sequencing. However, advances in sequencing technologies have improved the state of genomic resources for both wheat and barley. The availability of reference genomes for wheat and some of its progenitors,as well as for barley, sets the stage for answering unresolved questions in domestication genomics of wheat and barley. 相似文献