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61.
Zehra Hashim Amber Ilyas Ammara Saleem Asmat Salim Shamshad Zarina 《Free radical biology & medicine》2009,46(8):1089-1095
Paraoxonase 1 (PON1) is a high-density lipoprotein-associated enzyme that is believed to be involved in the protection against oxidative stress. There is evidence that paraoxonase activity is reduced in patients with diabetes and cataract. In the current study, we analyzed mRNA expression of PON1 as well as other members of the paraoxonase family, PON2 and PON3, in human cataractous lens samples. Our results indicate that only PON1 is expressed at the gene and protein levels in human lens tissues. We quantified MDA levels and measured PON1 (paraoxonase/arylesterase) enzymatic activities in subjects suffering from cataract due to aging and diabetes. Decreased PON1 activity was more pronounced in diabetic patients (p < 0.001) compared to senile subjects, which may be due to glycation and increased oxidative insult. To examine the structural alterations that occur in response to glycation, we constructed a three-dimensional model of PON1 and its glycated variant. Glycation at Lys70 and Lys75 is predicted to cause hindrance in binding of substrate to the active site of the enzyme. 相似文献
62.
Nampiah Sukarno Yuko Kurihara Muhammad Ilyas Wibowo Mangunwardoyo Erny Yuniarti Wellyzar Sjamsuridzal Ju-Young Park Rasti Saraswati Shigeki Inaba Yantyati Widyastuti Katsuhiko Ando Shigeaki Harayama 《Mycoscience》2009,50(5):369-379
Forty-six Lecanicillium strains and one Verticillium strain were isolated from subterranean and epiphytic arthropods, soil, and other sources collected in Indonesia and Japan. These strains were identified as nine Lecanicillium and one Verticillium species including six undescribed species based on light microscopy and the sequences of the ITS-1 and ITS-2 regions including 5.8S ribosomal DNA. Four of the ten species (L. araneicola, L. kalimantanense, Lecanicillium sp. 4, and V. indonesiacum) were recovered from Indonesia, five of the ten (L. attenuatum, L. fusisporum, L. psalliotae, Lecanicillium sp. 1, and Lecanicillium sp. 3) were from Japan, and L. saksenae was from both countries. In this article, new species (L. araneicola, L. kalimantanense, and V. indonesiacum) and a new combination (L. saksenae) are proposed from the fungi isolated from epiphytic and subterranean arthropods collected in East Kalimantan. 相似文献
63.
Kainat Masood Humaira Yasmin Sidra Batool Noshin Ilyas Asia Nosheen Rabia Naz Naeem Khan Muhammad Nadeem Hassan Adil Aldhahrani Fayez Althobaiti 《Saudi Journal of Biological Sciences》2021,28(9):4957-4968
Avian colibacillosis caused by the zoonotic pathogen Escherichia coli is a common bacterial infection that causes major losses in the poultry sector. Extracts of different medicinal plants and antibiotics have been used against poultry bacterial pathogens. However, overuse of antibiotics and extracts against pathogenic strains leads to the proliferation of multi-drug resistant bacteria. Due to their environmentally friendly nature, nanotechnology and beneficial bacterial strains can be used as effective strategies against poultry infections. Green synthesis of zinc oxide nanoparticles (ZnO-NPs) from Eucalyptus globulus leaves was carried out in this study. Their characterization was done by UV–vis spectroscopy, X-ray diffraction (XRD), and Fourier transmission infrared spectroscopy (FT-IR) which confirmed their synthesis, structure, and size. In vitro, antimicrobial activities of plant leaf extract, ZnO-NPs, and plant growth-promoting rhizobacteria (PGPR) were checked against E. coli using well diffusion as well as disc diffusion method. Results proved that the antimicrobial activity of ZnO-NPs and PGPR strains was more enhanced when compared to eucalyptus leaf extract at 36 h. The maximum relative inhibition shown by ZnO-NPs, PGPR strains and eucalyptus leaf extracts was 88%, 67% and 58%, respectively. The effectiveness of ZnO-NPs was also increased with an increase in particle dose and treatment time. The 90 mg/ml of ZnO-NPs was more effective. PGPR strains from all over the tested strains, Pseudomonas sp. (HY8N) exhibited a strong antagonism against the E. coli strain as compared to other PGPR strains used in this study. However, combined application of PGPR (Pseudomonas sp. (HY8N)) and ZnO-NPs augment antagonistic effects and showed maximum 69% antagonism. The study intends to investigate the binding affinity of ZnO-NPs with the suitable receptor of the bacterial pathogen by in silico methods. The binding site conformations showed that the ligand ZnO binds with conserved binding site of penicillin-binding protein 6 (PBP 6) receptor. According to the interactions, ZnO-NPs form the same interaction pattern with respect to other reported ligands, hence it can play a significant role in the inhibition of PBP 6. This research also found that combining ZnO-NPs with Pseudomonas sp. (HY8N) was a novel and effective technique for treating pathogenic bacteria, including multidrug-resistant bacteria. 相似文献
64.
Kaschani F Shabab M Bozkurt T Shindo T Schornack S Gu C Ilyas M Win J Kamoun S van der Hoorn RA 《Plant physiology》2010,154(4):1794-1804
Since the leaf apoplast is a primary habitat for many plant pathogens, apoplastic proteins are potent, ancient targets for apoplastic effectors secreted by plant pathogens. So far, however, only a few apoplastic effector targets have been identified and characterized. Here, we discovered that the papain-like cysteine protease C14 is a new common target of EPIC1 and EPIC2B, two apoplastic, cystatin-like proteins secreted by the potato (Solanum tuberosum) late blight pathogen Phytophthora infestans. C14 is a secreted protease of tomato (Solanum lycopersicum) and potato typified by a carboxyl-terminal granulin domain. The EPIC-C14 interaction occurs at a wide pH range and is stronger than the previously described interactions of EPICs with tomato defense proteases PIP1 and RCR3. The selectivity of the EPICs is also different when compared with the AVR2 effector of the fungal tomato pathogen Cladosporium fulvum, which targets PIP1 and RCR3, and only at apoplastic pH. Importantly, silencing of C14 increased susceptibility to P. infestans, demonstrating that this protease plays a role in pathogen defense. Although C14 is under conservative selection in tomato, it is under diversifying selection in wild potato species (Solanum demissum, Solanum verrucosum, and Solanum stoliniferum) that are the natural hosts of P. infestans. These data reveal a novel effector target in the apoplast that contributes to immunity and is under diversifying selection, but only in the natural host of the pathogen. 相似文献
65.
66.
Brittle rachis is a head shattering mechanism of barley. Two tightly linked complementary genes, btr1 and btr2, were believed to control the non-brittle rachis trait. Position of non-brittle rachis loci btr1btr2 on the short arm of Chromosome 3 was investigated using RFLP markers. Two approaches were employed. First, a Hordeum vulgare subsp. spontaneum fragment that confers brittleness in a cv. Bowman near isogenic line was detected. This fragment is 18-33 cM in length and contains MWG798B, ABG057, MWG014, BCD706 and KFP216 markers of the short arm of Chromosome 3. In the second approach, position of btr1 locus in a H. vulgare subsp. spontaneum (Wadi Qilt 23-38)xH. vulgare subsp. vulgare (cv. Harrington) cross was detected using a selective genotyping approach in BC2F1 generation. F-tests and analysis of genotypic compositions of BC2F1 lines showed that btr1 locus, and supposedly the tightly linked btr2 locus, is in 4.3 cM KFP216-RisP114 interval of short arm of Chromosome 3. Results also yielded clues for the presence of at least two additional loci that affect the non-brittle rachis trait. Allelism tests using genotypes with known non-brittle rachis gene compositions provided additional evidence for presence of such loci. 相似文献
67.
Crews DE Fitton LJ Kottke BA Kamboh MI 《American journal of physical anthropology》2004,124(4):364-372
Distributions of alleles at three apolipoprotein loci (APO E, APO H, and APO A-IV) and an insertion/deletion (I/D) polymorphism at the angiotensin converting enzyme (ACE) locus among 274 American Samoans are described here. Genotypes at each locus are examined for associations with quantitative lipid (total cholesterol (total-c), LDL-cholesterol (LDL-c), HDL-cholesterol (HDL-c), and triglycerides) and apolipoprotein (APO AI, APO AII, APO E, and APO B) levels. Genotype frequencies at all four loci are in Hardy-Weinberg equilibrium. The most common APO A-IV genotype (1-1) was observed in 252 American Samoans (97%). The three most common APO E genotypes were 3-3 (47%), 3-4 (30%), and 2-3 (12%). The most frequent APO H genotype was 2-2 (86%). The most common ACE genotype (I/I) was observed in 75% of sampled individuals, and 23% were I/D heterozygotes. APO E genotypic variation was associated with total-c, HDL-c, LDL-c, and all four quantitative apolipoproteins (AI, AII, E, and B). APO A-IV genotypes were associated significantly with total cholesterol, LDL-c, and APO-B levels. APO H showed little association with any quantitative lipid or apolipoprotein. ACE D/D homozygotes had higher AII levels. ACE showed a consistent association with APO AII levels, with either APO A-IV or APO E as a covariate. The interaction term between ACE and APO E was also significantly associated with total-c and APO E levels, and the ACE genotype showed a significant main effect on APO AI levels in multivariate analyses. 相似文献
68.
The continued studies on the constituents of the fresh leaves and stem bark of Plumeria obtusa Linn. have led to the isolation and characterization of four new triterpenoids, dammara-12,20(22)Z-dien-3-one (1), dammara-12,20(22)Z-dien-3beta-ol (2), olean-12-en-3beta,27-diol (3), and 27-hydroxyolean-12-en-3-one (4) and 12 known compounds, which included eight triterpenoids; dammara-3beta,20(S),25-triol (5), urs-12-en-3beta-hydroxy-27-Z-feruloyloxy-28-oic acid (6), 3beta-hydroxyolean-12-en-28-oic acid (7), 3beta,27-dihydroxylupan-29-ene (8), 3beta-hydroxylupan-29-en-28-oic acid (9), 3beta-hydroxyursan-12-en-28-oic acid (11), 3beta-hydroxy-27-p-coumaroyloxy-olea-12-en-28-oic acid (12) and urs-12-en-3-one (15); an iridoid 1alpha-plumieride (10); a cardenolide 3alpha,14beta-dihydroxy-17beta-card-20(22)-enolide (13); a fatty acid ester methyl n-octadecanoate (14) and a steroid 3beta-hydroxy-delta5-stigmastane (16). The new constituents were characterized through spectroscopic studies including 1D (1H and 31C NMR) and 2D (COSY-45, NOESY, J-resolved, HMQC and HMBC) NMR and chemical transformations. This is the first report on the isolation of dammarane triterpenoids from P. obtusa. Compounds 5 and 6 are hitherto unreported from P. obtusa. The known compounds were identified by comparison of their spectral data with those reported in the literature. 相似文献
69.
Siddiqui BS Rasheed M Ilyas F Gulzar T Tariq RM Naqvi SN 《Zeitschrift für Naturforschung. C, Journal of biosciences》2004,59(1-2):104-112
As a result of chemical investigation on the ethanolic extract of fresh fruit coatings of Azadirachta indica A. Juss. (neem), twenty-seven compounds were identified in non-polar to less polar fractions which showed pesticidal activity determined by WHO method against Anopheles stephensi Liston. These identifications were basically made through GC-EIMS and were further supported by other spectroscopic techniques, including 13C NMR, UV and FTIR as well as retention indices. Thus sixteen n-alkanes, 1-16; three aromatics 2,6-bis-(1,1-dimethylethyl)-4-methyl phenol (17), 2-(phenylmethylene)-octanal (20), 1,2,4-trimethoxy-5-(1Z-propenyl)-benzene (27); three benzopyranoids 3,4-dihydro-4,4,5,8-tetramethylcoumarin (18), 3,4-dihydro-4,4,7,8-tetramethylcoumarin-6-ol (19), 1,3,4,6,7,8-hexahydro-4,6,6,7,8,8-hexamethyl-cyclopenta[g]-2-benzopyran (22); one sesquiterpene methyl-3,7,11-trimethyl-2E,6E,10-dodecatrienoate (21); three esters of fatty acids methyl 14-methyl-pentadecanoate (23), ethyl hexadecanoate (24), ethyl 9Z-octadecenoate (25) and one monoterpene 3,7-dimethyl-1-octen-7-ol (26) were identified. Except 6, 8, 24 and 25 all these compounds were identified for the first time from the pericarp and fifteen of these, 1-3, 7, 9, 10, 17-23, 26, 27, are hitherto unreported previously from any part of the tree. Although this tree is a rich source of various natural products, it is the first report of identification of mono- and sesquiterpenes 26 and 21 and a potent antioxidant, 17. 相似文献
70.