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191.
Kavusi Elaheh Shahi Khalaf Ansar Behnaz Dehghanian Zahra Asgari Lajayer Behnam Nobaharan Khatereh Ma Ying Glick Bernard R. 《Journal of Plant Growth Regulation》2023,42(2):575-597
Journal of Plant Growth Regulation - Medicinal and aromatic plants (MAPs) producing a myriad of chemicals can be utilized in numerous sectors such as pharmaceutical products, feed and food... 相似文献
192.
Molecular phylogeny of the lionfish genera Dendrochirus and Pterois (Scorpaenidae,Pteroinae) based on mitochondrial DNA sequences 总被引:3,自引:0,他引:3
This study investigates the molecular phylogeny of seven lionfishes of the genera Dendrochirus and Pterois. MP, ML, and NJ phylogenetic analysis based on 964 bp of partial mitochondrial DNA sequences (cytochrome b and 16S rDNA) revealed two main clades: (1) "Pterois" clade (Pterois miles and Pterois volitans), and (2) "Pteropterus-Dendrochirus" clade (remainder of the sampled species). The position of Dendrochirus brachypterus either basal to the main clades or in the "Pteropterus-Dendrochirus" clade cannot be resolved. However, the molecular phylogeny did not support the current separation of the genera Pterois and Dendrochirus. The siblings P. miles and P. volitans are clearly separated and our results support the proposed allopatric or parapatric distribution in the Indian and Pacific Ocean. However, the present analysis cannot reveal if P. miles and P. volitans are separate species or two populations of a single species, because the observed separation in different clades can be either explained by speciation or lineage sorting. Molecular clock estimates for the siblings P. miles and P. volitans suggest a divergence time of 2.4-8.3 mya, which coincide with geological events that created vicariance between populations of the Indian and Pacific Ocean. 相似文献
193.
Association between HLA Variations and Chronic Hepatitis B Virus Infection in Saudi Arabian Patients
Ahmed A. Al-Qahtani Mashael R. Al-Anazi Ayman A. Abdo Faisal M. Sanai Waleed Al-Hamoudi Khalid A. Alswat Hamad I. Al-Ashgar Nisreen Z. Khalaf Abdelmoneim M. Eldali Nisha A. Viswan Mohammed N. Al-Ahdal 《PloS one》2014,9(1)
Hepatitis B virus (HBV) infection is a leading cause of liver diseases including cirrhosis and hepatocellular carcinoma. Human leukocyte antigens (HLAs) play an important role in the regulation of immune response against infectious organisms, including HBV. Recently, several genome-wide association (GWAS) studies have shown that genetic variations in HLA genes influence disease progression in HBV infection. The aim of this study was to investigate the role of HLA genetic polymorphisms and their possible role in HBV infection in Saudi Arabian patients. Variations in HLA genes were screened in 1672 subjects who were divided according to their clinical status into six categories as follows; clearance group, inactive carriers, active carriers, cirrhosis, hepatocellular carcinoma (HCC) patients and uninfected healthy controls. Three single nucleotide polymorphisms (SNPs) belonged to HLA-DQ region (rs2856718, rs7453920 and rs9275572) and two SNPs belonged to HLA-DP (rs3077 and rs9277535) were studied. The SNPs were genotyped by PCR-based DNA sequencing (rs2856718) and allele specific TaqMan genotyping assays (rs3077, rs7453920, rs9277535 and rs9275572). The results showed that rs2856718, rs3077, rs9277535 and rs9275572 were associated with HBV infection (p = 0.0003, OR = 1.351, CI = 1.147–1.591; p = 0.041, OR = 1.20, CI = 1.007–1.43; p = 0.045, OR = 1.198, CI = 1.004–1.43 and p = 0.0018, OR = 0.776, CI = 0.662–0.910, respectively). However, allele frequency of rs2856718, rs7453920 and rs9275572 were found more in chronically infected patients when compared to clearance group infection (p = 0.0001, OR = 1.462, CI = 1.204–1.776; p = 0.0178, OR = 1.267, CI = 1.042–1.540 and p = 0.010, OR = 0.776, CI = 0.639–0.942, respectively). No association was found when polymorphisms in HLA genes were compared in active carriers versus cirrhosis/HCC patients. In conclusion, these results suggest that variations in HLA genes could affect susceptibility to and clearance of HBV infection in Saudi Arabian patients. 相似文献
194.
Six hundred water samples collected from the river Tigris at Mosul City were investigated for faecal streptococci. Human faecal streptococci were predominant, and animal faecal streptococci were also detected. Eight species and varieties were identified, viz Streptococcus faecalis, atypical Streptococcus faecalis, Streptococcus bovis, Streptococcus equinus, Streptococcus faecalis var. liquefaciens, Streptococcus faecalis var. zymogenes, Streptococcus durans and Streptococcus faecium. The incidence of these species and varieties were 43.32%, 13.18%, 11.47%, 11.30%, 9.76%, 5.30%, 3.76% and 1.88%, respectively. 相似文献
195.
This work aims at investigating different types and levels of hydrophilic matrixing agents, including methylcellulose (MC), sodium alginate (Alg), and sodium carboxymethylcellulose (CMC), in an attempt to formulate controlled-release matrix tablets containing 25 mg baclofen. The tablets were prepared by wet granulation. Prior to compression, the prepared granules were evaluated for flow and compression characteristics. In vitro, newly formulated controlled-release tablets were compared with standard commercial tablets (Lioresal and baclofen). The excipients used in this study did not alter physicochemical properties of the drug, as tested by the thermal analysis using differential scanning calorimetry. The flow and compression characteristics of the prepared granules significantly improved by virtue of granulation process. Also, the prepared matrix tablets showed good mechanical properties (hardness and friability). MC- and Alg-based tablet formulations showed high release-retarding efficiency, and good reproducibility and stability of the drug release profiles when stored for 6 months in ambient room conditions, suggesting that MC and Alg are good candidates for preparing modified-release baclofen tablet formulations. 相似文献
196.
Ossama Khalaf Bruno Fauvet Abid Oueslati Igor Dikiy Anne-Laure Mahul-Mellier Francesco Simone Ruggeri Martial K. Mbefo Filip Vercruysse Giovanni Dietler Seung-Jae Lee David Eliezer Hilal A. Lashuel 《The Journal of biological chemistry》2014,289(32):21856-21876
Over the last two decades, the identification of missense mutations in the α-synuclein (α-Syn) gene SNCA in families with inherited Parkinson disease (PD) has reinforced the central role of α-Syn in PD pathogenesis. Recently, a new missense mutation (H50Q) in α-Syn was described in patients with a familial form of PD and dementia. Here we investigated the effects of this novel mutation on the biophysical properties of α-Syn and the consequences for its cellular function. We found that the H50Q mutation affected neither the structure of free or membrane-bound α-Syn monomer, its interaction with metals, nor its capacity to be phosphorylated in vitro. However, compared with the wild-type (WT) protein, the H50Q mutation accelerated α-Syn fibrillization in vitro. In cell-based models, H50Q mutation did not affect α-Syn subcellular localization or its ability to be phosphorylated by PLK2 and GRK6. Interestingly, H50Q increased α-Syn secretion from SHSY5Y cells into culture medium and induced more mitochondrial fragmentation in hippocampal neurons. Although the transient overexpression of WT or H50Q did not induce toxicity, both species induced significant cell death when added to the culture medium of hippocampal neurons. Strikingly, H50Q exhibited more toxicity, suggesting that the H50Q-related enhancement of α-Syn aggregation and secretion may play a role in the extracellular toxicity of this mutant. Together, our results provide novel insight into the mechanism by which this newly described PD-associated mutation may contribute to the pathogenesis of PD and related disorders. 相似文献
197.
When rat pancreatic islets were incubated with 10(-8) M arginine vasopressin in the presence of 15 mM glucose there was a pronounced inhibition of insulin release in comparison with controls. This inhibitory effect appeared to be specific for vasopressin since it was antagonised by vasopressin antibody. Moreover, pertussis toxin (100 ng/ml) reversed the inhibition of insulin release due to vasopressin, indicating the possible involvement of a guanyl-nucleotide regulatory protein in the inhibitory effect. Nevertheless, 10(-8) M vasopressin increased islet concentrations of cyclic AMP even under conditions where insulin release was decreased. 相似文献
198.
Stefek M Snirc V Djoubissie PO Majekova M Demopoulos V Rackova L Bezakova Z Karasu C Carbone V El-Kabbani O 《Bioorganic & medicinal chemistry》2008,16(9):4908-4920
Starting from the efficient hexahydropyridoindole antioxidant stobadine, a series of carboxymethylated tetrahydro- and hexahydropyridoindole derivatives was synthesized and tested for the inhibition of aldose reductase, an enzyme involved in the etiology of diabetic complications. In vitro inhibiton of rat lens aldose reductase was determined by a conventional method. Kinetic analysis of (2-benzyl-2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indole-8-yl)-acetic acid (5b) and (2-phenethyl-2,3,4,5-tetrahydro-1H-pyrido[4,3-b]indole-8-yl)-acetic acid (5c), the most potent compounds in this series with activities in micromolar range, showed uncompetitive inhibition. In addition to the importance of the acidic function, the inhibition efficacy was highly influenced by the steric conformation of the lipophilic aromatic backbone when comparing tetrahydro- and hexahydropyridoindole congeners. Selectivity with respect to the closely related aldehyde reductase was determined by measuring the corresponding inhibitory activities. Antioxidant action of the novel compounds was documented in a DPPH test and in a liposomal membrane model, oxidatively stressed by peroxyl radicals. The presence of a basicity center at the tertiary nitrogen, in addition to the acidic carboxylic function, predisposes these compounds to form double charged zwitterionic species, a characteristic which may remarkably affect their pH-lipophilicity profile. For compounds 5b and 5c, a maximal distribution ratio in a system comprised of 1-octanol/phosphate buffer was recorded near the neutral physiological pH, the region where the isoelectric point lies. Molecular docking simulations into the ALR2 active site performed for the zwitterionic species provided an explanation for the observed structure–activity relationships and the calculated parameters were in agreement with characteristic differences in the stereoelectronic profiles of the tetrahydro- versus hexahydropyridoindoles. ‘Drug-likeness’ of the novel aldose reductase inhibitors was assessed by applying the criteria of Lipinski’s ‘rule of five’. 相似文献
199.
Endo S Matsunaga T Ohta C Soda M Kanamori A Kitade Y Ohno S Tajima K El-Kabbani O Hara A 《Chemico-biological interactions》2011,191(1-3):261-268
Farnesol (FOH) and geranylgeraniol (GGOH) with multiple biological actions are produced from the mevalonate pathway, and catabolized into farnesoic acid and geranylgeranoic acid, respectively, via the aldehyde intermediates (farnesal and geranylgeranial). We investigated the intracellular distribution, sequences and properties of the oxidoreductases responsible for the metabolic steps in rat tissues. The oxidation of FOH and GGOH into their aldehyde intermediates were mainly mediated by alcohol dehydrogenases 1 (in the liver and colon) and 7 (in the stomach and lung), and the subsequent step into the carboxylic acids was catalyzed by a microsomal aldehyde dehydrogenase. In addition, high reductase activity catalyzing the aldehyde intermediates into FOH (or GGOH) was detected in the cytosols of the extra-hepatic tissues, where the major reductase was identified as aldo-keto reductase (AKR) 1C15. Human reductases with similar specificity were identified as AKR1B10 and AKR1C3, which most efficiently reduced farnesal and geranylgeranial among seven enzymes in the AKR1A-1C subfamilies. The overall metabolism from FOH to farnesoic acid in cultured cells was significantly decreased by overexpression of AKR1C15, and increased by addition of AKR1C3 inhibitors, tolfenamic acid and R-flurbiprofen. Thus, AKRs (1C15 in rats, and 1B10 and 1C3 in humans) may play an important role in controlling the bioavailability of FOH and GGOH. 相似文献
200.