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41.
Ammar Almaaytah Adan Alnaamneh Ahmad Abualhaijaa Nizar Alshari’ Qosay Al-Balas 《International journal of peptide research and therapeutics》2016,22(4):497-504
The extensive use of antibiotics for the treatment of human infections during the last few decades has led to a dramatic increase in the emergence of multidrug-resistant bacteria (MDRB) among various bacterial strains. Global research is currently focused on finding novel alternative agents with different mechanisms of action rather than the use of conventional antibiotics to counteract the threat of bacterial and biofilm infections. Antimicrobial peptides represent promising alternative agents for conventional antibiotics as these molecules display a broad spectrum of activity against several microorganisms. Recently, we have designed a novel hybrid antimicrobial peptide named MelitAP-27. This peptide has been found to display potent broad spectrum and selective in vitro antimicrobial activities against a wide range of Gram-positive and Gram-negative bacteria. In the present study, the in vitro antimicrobial and antibiofilm activities of the peptide alone and in combination with five different types of antibiotics were assessed against wild-type and resistant Gram-positive and Gram-negative bacterial strains. Our results showed that most of the combination groups displayed a synergistic mode of action against planktonic and biofilm forming bacteria which resulted in decreasing the effective MIC values for MelitAP-27 to the nanomolar concentrations. These effective concentrations were associated with negligible toxicities on mammalian cells. The results of our study indicate that combinations of MelitAP-27 with conventional antibiotics may be pursued as a potential novel treatment strategy against MDRB and biofilm forming bacteria. 相似文献
42.
Julien Benoit El Mabrouk Essid Wissem Marzougui Hayet Khayati Ammar Renaud Lebrun Rodolphe Tabuce Laurent Marivaux 《Journal of human evolution》2013
We report the discovery of three isolated primate petrosal fragments from the fossiliferous locality of Chambi (Tunisia), a primate-bearing locality dating from the late early to the early middle Eocene. These fossils display a suite of anatomical characteristics otherwise found only in strepsirhines, and as such might be attributed either to Djebelemur or/and cf. Algeripithecus, the two diminutive stem strepsirhine primates recorded from this locality. Although damaged, the petrosals provide substantial information regarding the ear anatomy of these advanced stem strepsirhines (or pre-tooth-combed primates), notably the patterns of the pathway of the arterial blood supply. Using μCT-scanning techniques and digital segmentation of the structures, we show that the transpromontorial and stapedial branches of the internal carotid artery (ICA) were present (presence of bony tubes), but seemingly too small to supply enough blood to the cranium alone. This suggests that the ICA was not the main cranial blood supply in stem strepsirhines, but that the pharyngeal or vertebral artery primitively ensured a great part of this role instead, an arterial pattern that is reminiscent of modern cheirogaleid, lepilemurid lemuriforms and lorisiforms. This could explain parallel loss of the ICA functionality among these families. Specific measurements made on the cochlea indicate that the small strepsirhine primate(s) from Chambi was (were) highly sensitive to high frequencies and poorly sensitive to low frequencies. Finally, variance from orthogonality of the plane of the semicircular canals (SCs) calculated on one petrosal (CBI-1-569) suggests that Djebelemur or cf. Algeripithecus likely moved (at least its head) in a way similar to that of modern mouse lemurs. 相似文献
43.
Iman Al-Saleh Mai Abduljabbar Reem Al-Rouqi Rola Elkhatib Ammar Alshabbaheen Neptune Shinwari 《Biological trace element research》2013,153(1-3):145-154
The objective of this work was to assess exposure to mercury (Hg) and its induction of oxidative stress in 155 healthy lactating Saudi mothers and their infants. Samples of breast milk and blood were collected from the mothers, while urine was taken from both infants and mothers. Both urinary 8-hydroxy-2′-deoxyguanosine (8-OHdG) and malondialdehyde (MDA) were measured in mothers and infants as biomarkers of oxidative stress. The mean concentration of Hg in breast milk was 1.19 μg/L (range 0.012–6.44 μg/L) with only one mother having Hg >4 μg/L, the upper limit established by the US Agency for Toxic Substance and Disease Registry. However, 57.4 % had Hg ≥1 μg/L, the background level for Hg in human milk. The mean urinary Hg corrected for creatinine (Hg-C) in mothers and infants was 1.47 and 7.90 μg/g creatinine, respectively, with a significant correlation between the two (p?<?0.001). Urinary Hg levels over 5 μg/g creatinine (the background level in an unexposed population) were found in 3.3 % of mothers and 50.1 % of infants. None of the mothers had total blood Hg above the US Environmental Protection Agency’s maximum reference dose of 5.8 μg/L. No correlation was noted between urinary Hg in infants and Hg in breast milk (p?>?0.05). Hg in breast milk, though, was associated with Hg in blood (p?<?0.001), suggesting the efficient transfer of Hg from blood to milk. Hg in the breast milk of mothers and in the urine of infants affected the excretion of urinary MDA and 8-OHdG, respectively, in a dose-related manner. These findings reveal for the first time lactational exposure to Hg-induced oxidative stress in breast-fed infants, which may play a role in pathogenesis, particularly during neurodevelopment. This will also contribute to the debate over the benefits of breast milk versus the adverse effects of exposure to pollutants. Nevertheless, breastfeeding should not be discouraged, but efforts should be made to identify and eliminate the source of Hg exposure in the population. 相似文献
44.
Remon M. Zaki Adel M. Kamal El-Dean Radwan Shaban M. Ammar Mahmoud A. 《Russian Journal of Bioorganic Chemistry》2020,46(1):85-96
Russian Journal of Bioorganic Chemistry - We describe a simple method to synthesize novel 4-cyano-1-morpholin-4-yl-6,7-dihydro-5H-cyclopenta[c]pyridine-3-thione by the reaction of... 相似文献
45.
Ben Ammar Y Matsubara T Ito K Iizuka M Limpaseni T Pongsawasdi P Minamiura N 《Journal of biotechnology》2002,99(2):111-119
A thermoactive and thermostable levansucrase was purified from a newly isolated thermophilic Bacillus sp. from Thailand soil. The purification was achieved by alcohol precipitation, DEAE-Cellulose and gel filtration chromatographies. The enzyme was purified to homogeneity as determined by SDS-PAGE, and had a molecular mass of 56 kDa. This levansucrase has some interesting characteristics regarding its optimum temperature and heat stability. The optimum temperature and pH were 60 degrees C and 6.0, respectively. The enzyme was completely stable after treatment at 50 degrees C for more than 1 h, and its activity increased four folds in the presence of 5 mM Fe(2+). The optimum temperature for levan production was 50 degrees C. Contrary to other levansucrases, the one presented in this study is able to produce high molecular weight levan at 50 degrees C. 相似文献
46.
Salem S. Alghamdi Muhammad A. Khan Ehab H. El-Harty Megahed H. Ammar Muhammad Farooq Hussein M. Migdadi 《Saudi Journal of Biological Sciences》2018,25(1):15-21
This study aimed to estimate the proximate, phenolic and flavonoids contents and phytochemicals present in seeds of twenty four soybeans (Glycine max (L.) Merr) genotypes to explore their nutritional and medicinal values. Crude protein composition ranged between 35.63 and 43.13% in Argentinian and USA (Clark) genotypes, respectively. Total phenolic content varied from 1.15 to 1.77?mg?GAE/g, whereas flavonoids varied from 0.68 to 2.13?mg?QE/g. The GC–MS analysis resulted identification of 88 compounds categorized into aldehydes (5), ketones (13), alcohols (5), carboxylic acids (7), esters (13), alkanes (2), heterocyclic compounds (19), phenolic compound (9), sugar moiety (7) ether (4) and amide (3), one Alkene and one fatty acid ester. Indonesian genotypes (Ijen and Indo-1) had the highest phenolic compounds than others genotype having antioxidant activities, while the Australian genotype contains the maximum in esters compounds. The major phytocompounds identified in majority of genotypes were Phenol, 2,6-dimethoxy-, 2-Methoxy-4-vinylphenol, 3,5-Dimethoxyacetophenone, 1,2-cyclopentanedione and Hexadecanoic acid, methyl ester. The presence of phytochemicals with strong pharmacological actions like antimicrobial and antioxidants activities could be considered as sources of quality raw materials for food and pharmaceutical industries. This study further set a platform for isolating and understanding the characteristics of each compound for it pharmacological properties. 相似文献
47.
Nadine?AME?van der BeekEmail author Juna?M?de Vries Marloes?LC?Hagemans Wim?CJ?Hop Marian?A?Kroos John?HJ?Wokke Marianne?de Visser Baziel?GM?van Engelen Jan?BM?Kuks Anneke?J?van der Kooi Nicolette?C?Notermans Karin?G?Faber Jan?JGM?Verschuuren Arnold?JJ?Reuser Ans?T?van der Ploeg Pieter?A?van Doorn 《Orphanet journal of rare diseases》2012,7(1):88
Background
Due partly to physicians’ unawareness, many adults with Pompe disease are diagnosed with great delay. Besides, it is not well known which factors influence the rate of disease progression, and thus disease outcome. We delineated the specific clinical features of Pompe disease in adults, and mapped out the distribution and severity of muscle weakness, and the sequence of involvement of the individual muscle groups. Furthermore, we defined the natural disease course and identified prognostic factors for disease progression.Methods
We conducted a single-center, prospective, observational study. Muscle strength (manual muscle testing, and hand-held dynamometry), muscle function (quick motor function test), and pulmonary function (forced vital capacity in sitting and supine positions) were assessed every 3–6 months and analyzed using repeated-measures ANOVA.Results
Between October 2004 and August 2009, 94 patients aged between 25 and 75 years were included in the study. Although skeletal muscle weakness was typically distributed in a limb-girdle pattern, many patients had unfamiliar features such as ptosis (23%), bulbar weakness (28%), and scapular winging (33%). During follow-up (average 1.6 years, range 0.5-4.2 years), skeletal muscle strength deteriorated significantly (mean declines of ?1.3% point/year for manual muscle testing and of ?2.6% points/year for hand-held dynamometry; both p<0.001). Longer disease duration (>15 years) and pulmonary involvement (forced vital capacity in sitting position <80%) at study entry predicted faster decline. On average, forced vital capacity in supine position deteriorated by 1.3% points per year (p=0.02). Decline in pulmonary function was consistent across subgroups. Ten percent of patients declined unexpectedly fast.Conclusions
Recognizing patterns of common and less familiar characteristics in adults with Pompe disease facilitates timely diagnosis. Longer disease duration and reduced pulmonary function stand out as predictors of rapid disease progression, and aid in deciding whether to initiate enzyme replacement therapy, or when.48.
Gaci Meriem Benhizia Yacine Dems Mohamed AbdEsselem Boukaous Leyla Benguedouar Ammar Hynes Michael Francis 《Plant and Soil》2021,461(1-2):369-388
Plant and Soil - The nitrogen-fixing symbiosis fixation between legumes and Rhizobium helps the plant to survive and to compete effectively on nitrogen poor soils. The soil environment attached to... 相似文献
49.
Saleem A Engström M Wurster S Savola JM Pihlaja K 《Zeitschrift für Naturforschung. C, Journal of biosciences》2002,57(3-4):332-338
Forty-two extracts of folk medicinal plant organs from Pakistan were tested in competition binding assays for their interaction with the specific ligand recognition sites on the human alpha2-adrenoceptor subtypes alpha2A, alpha2B and alpha2C Strong binding of the extracts (40 mg/ml) from Acacia nilotica (L.) Delile leaves (88-98% displacement of radiolabel) and Peganum harmala seeds (89-96% displacement) on three subtypes prompted us to extract these plant materials with 40% and 80% methanol, ethanol, and acetone. The extraction results indicated an absence of alpha2-adrenoceptor binding activity in the stalk of A. nilotica and A. tortils, whereas the leaves of both plants contained activity. The extracts of A. nilotica leaves showed a slight, but consistent, preference for the alpha2C-adrenoceptor, whereas the leaves of A. tortils were slightly more active on the alpha2B subtype. The extract of P. harmala stalks was less active than that of its seeds. The binding activities of A. nilotica leaves and P. harmala seeds were mainly concentrated in the water and 30% methanol fractions and further sub-fractions. In a functional activity assay, the active fractions inhibited epinephrine-stimulated 35S-GTPyS binding, thus indicating a predominantly antagonistic nature of the compounds with alpha2-adrenoceptor affinity in these fractions. Among the known major alkaloids of P. harmala (demissidine, harmaline, harmine, 6-methoxyharmalan, and norharmane), only 6-methoxyharmalan showed moderate affinity (dissociation constant (Ki) of 530 +/- 40 nm for alpha2A subtype). This study is a first systematic attempt towards the discovery of potential drug candidates from these plant materials for treating alpha2-adrenoceptor related diseases. 相似文献
50.
Sebastian Dolff Daniel Quandt Benjamin Wilde Thorsten Feldkamp Fan Hua Xin Cai Christof Specker Andreas Kribben Cees GM Kallenberg Oliver Witzke 《Arthritis research & therapy》2010,12(4):R150