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111.
The transport of more than 90% of the drugs viz. anticoagulants, analgesics, and general anesthetics in the blood takes place by albumin. Hence, albumin is the prime protein needs to be investigated to find out the nature of drug binding. Serum albumin molecules are prone to glycation at elevated blood glucose levels as observed in diabetics. In this piece of work, glycation of bovine serum albumin (BSA) was carried out with glyceraldehyde and characterized by molecular docking and fluorometry techniques. Glycation of BSA showed 25% loss of free amino groups and decreased protein fluorescence (60%) with blue shift of 6 nm. The present study was also designed to evaluate the binding of colchicine (an anti-inflammatory drug) to native and glycated BSA and its ability to displace 8-analino-1-nephthalene sulfonic acid (ANS), from the BSA–ANS complex. Binding of ANS to BSA showed strong binding (Ka = 4.4 μM) with native conformation in comparison to glycated state (Ka = 8.4 μM). On the other hand, colchicine was able to quench the fluorescence of native BSA better than glycated BSA and also showed weaker affinity (Ka = 23 μM) for glycated albumin compared with native state (Ka = 16 μM). Molecular docking study showed that both glyceraldehyde and colchicine bind to common residues located near Sudlow’s site I that explain the lower binding of colchicine in the glycated BSA. Based on our results, we believe that reduced drugs-binding affinity to glycated albumin may lead to drugs accumulation and precipitation in diabetic patients.  相似文献   
112.
The ability of Legionella pneumophila to cause pneumonia is determined by its capability to evade the immune system and grow within human monocytes and their derived macrophages. Human monocytes efficiently activate caspase-1 in response to Salmonella but not to L. pneumophila. The molecular mechanism for the lack of inflammasome activation during L. pneumophila infection is unknown. Evaluation of the expression of several inflammasome components in human monocytes during L. pneumophila infection revealed that the expression of the apoptosis-associated speck-like protein (ASC) and the NOD-like receptor NLRC4 are significantly down-regulated in human monocytes. Exogenous expression of ASC maintained the protein level constant during L. pneumophila infection and conveyed caspase-1 activation and restricted the growth of the pathogen. Further depletion of ASC with siRNA was accompanied with improved NF-κB activation and enhanced L. pneumophila growth. Therefore, our data demonstrate that L. pneumophila manipulates ASC levels to evade inflammasome activation and grow in human monocytes. By targeting ASC, L. pneumophila modulates the inflammasome, the apoptosome, and NF-κB pathway simultaneously.  相似文献   
113.
The ant genus Meranoplus is reported for the first time from the Arabian Peninsula (Kingdom of Saudi Arabia) by the new species M. pulcher sp. n., based on the worker caste. Specimens were collected from Al Sarawat and Asir Mountains of southwestern Kingdom of Saudi Arabia using pitfall traps. Meranoplus pulcher sp. n. is included in the Afrotropical M. magretii-group, with greatest similarity to M. magrettii André from Sudan. A key to the Afrotropical species of the M. magretii-group is presented. A brief review of the ant taxa with Afrotropical affinities in southwestern region of the Kingdom of Saudi Arabia is given.  相似文献   
114.
Technomyrmex montaserisp. n. is described and illustrated from Oman based on the worker caste collected in Bani Sur. It belongs to the Technomyrmex gibbosus-group, with closest resemblance to Technomyrmex vexatus (Santschi, 1919) and Technomyrmex gibbosus W. M. Wheeler, 1906. A key to the Arabian Technomyrmex is given.  相似文献   
115.
Cystic fibrosis (CF) is the most common inherited lethal disease of Caucasians which results in multi organ dysfunction. However, 85% of the deaths are due to pulmonary infections. Infection by Burkholderia cenocepacia (B. cepacia) is a particularly lethal threat to CF patients because it causes severe and persistent lung inflammation and is resistant to nearly all available antibiotics. In CFTR ΔF508 mouse macrophages, B. cepacia persists in vacuoles that do not fuse with the lysosomes and mediates increased production of IL-1β. It is believed that intracellular bacterial survival contributes to the persistence of the bacterium. Here we show for the first time that in wild-type macrophages but not in ΔF508 macrophages, many B. cepacia reside in autophagosomes that fuse with lysosomes at later stages of infection. Accordingly, association and intracellular survival of B. cepacia are higher in CFTR-ΔF508 (ΔF508) macrophages than in WT macrophages. An autophagosome is a compartment that engulfs non-functional organelles and parts of the cytoplasm then delivers them to the lysosome for degradation to produce nutrients during periods of starvation or stress. Furthermore, we show that B. cepacia downregulates autophagy genes in WT and ΔF508 macrophages. However, autophagy dysfunction is more pronounced in ΔF508 macrophages since they already have compromised autophagy activity. We demonstrate that the autophagy-stimulating agent, rapamycin markedly decreases B. cepacia infection in vitro by enhancing the clearance of B. cepacia via induced autophagy. In vivo, Rapamycin decreases bacterial burden in the lungs of CF mice and drastically reduces signs of lung inflammation. Together, our studies reveal that if efficiently activated, autophagy can control B. cepacia infection and ameliorate the associated inflammation. Therefore, autophagy is a novel target for new drug development for CF patients to control B. cepacia infection and accompanying inflammation.  相似文献   
116.
This study aimed to evaluate amino acids content and the electrophoretic profile of camel milk casein from different camel breeds. Milk from three different camel breeds (Majaheim, Wadah and Safrah) as well as cow milk were used in this study.Results showed that ash and moisture contents were significantly higher in camel milk casein of all breeds compared to that of cow milk. On the other hand, casein protein of cow milk was significantly higher compared to that of all camel milk breeds. Molecular weights of casein patterns of camel milk breeds were higher compared to that of cow milk.Essential (Phe, Lys and His) and non-essential amino acids content was significantly higher in cow milk casein compared to the casein of all camel milk breeds. However, there was no significant difference for the other essential amino acids between cow casein and the casein of Safrah breed and their quantities in cow and Safrah casein were significantly higher compared to the other two breeds. Non-essential amino acids except Arg and the essential amino acids (Met, Ile, Lue and Phe) were also significantly higher in cow milk α-casein compared to α-casein from all camel breeds. Moreover, essential amino acids (Val, Phe and His) and the non-essential amino acids (Gly and Ser) content was significantly higher in cow milk β-casein compared to the β-casein of all camel milk breeds and the opposite was true for Lys, Thr, Met and Ile. However, Met, Ile, Phe and His were significantly higher for β-casein of Majaheim compared to the other two milk breeds. The non-essential amino acids (Gly, Tyr, Ala and Asp) and the essential amino acids (Thr, Val and Ile) were significantly higher in cow milk κ-casein compared to that for all camel milk breeds. There was no significant difference among all camel milk breeds in their κ-casein content of most essential amino acids.Relative migration of casein bands of camel milk casein was not identical. The relative migration of αs-, β- and κ-casein of camel casein was slower than those of cow casein. The molecular weights of αs-, β- and κ-casein of camel caseins were 27.6, 23.8 and 22.4 KDa, respectively. More studies are needed to elucidate the structure of camel milk.  相似文献   
117.
Antibacterial and cytotoxic activities of Euphorbia balsamifera, fractions and pure compounds were evaluated. The cytotoxic assays for HCT116, HePG2 and MCF7 showed a significant IC50: 54.7 and 76.2 µg/mL of non-polar fraction “n-hexane” against HCT116 and HePG2, respectively. Antibacterial results revealed that plant fractions exhibited significant potential against the tested pathogens than the total extract where n-butanol and ethyl acetate fractions showed significant antibacterial activity (P < 0.05) against tested bacterial strains. Isolation and structure determination of compounds from n-hexane and n-butanol fractions were performed. From n-hexane fraction, 29-nor-cycloartanol (1), lanost-8-en-3-ol (2a), cycloartanol (2b) and kampferol-3,4'-dimethyl ether (3) were isolated and structurally identified, along with 24 compounds were tentatively identified by GC–MS. From the polar n-butanol fraction, 4-O-β-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone (4), 4-O-α-L-rhamnosyl-(1 → 6)-β-D-glucopyranosyl-2-hydroxy-6methoxy-acetophenone (5), quercetin-3-O-glucopyranoside (6) and isoorientin (7) were assigned. Structures of the obtained compounds were determined by nuclear magnetic resonance (NMR) spectroscopy and mass spectrometry. Except compounds 1 and 5, all reported compounds announced antibacterial efficiency. Compound 2 showed selectively the highest activity against Enterococcus faecalis (22 ± 0.13 mm), meanwhile 4-O-β-D-glucopyranosyl-2-hydroxy-6-methoxyacetophenone (4) showed broadly the highest antibacterial activity with MIC of 1.15–1.88 mg/mL against the test Gram-positive and Gram-negative bacteria. Cytotoxic assays indicated that kampferol-3,4'-dimethyl ether (3) exhibited the highest activity with matching IC50 values to doxorubicin; 111.46, 42.67 and 44.90 µM against HCT116, HePG2 and MCF7, respectively, however, it is toxic on retina normal cell line RPE1.  相似文献   
118.
Airborne Pollen grains and Spores of three different cities viz., Al-Khobar (1987–1988), Abha (1991–1992) and Hofuf (1992–1993) in Saudi Arabia were studied using Burkard Volumetric Seven-Day Spore Trap. The data were analyzed in relation to their allergenic capability and one-year pollen and spore calendars were designed to correlate the patients’ symptoms as well as for selection of appropriate allergen extracts for diagnosis and treatment of allergic diseases. Amongst pollen group, Amaranthus viridis, Plantago spp., Chenopodium album, Ricinus communis, Rumex vesicarius, Juniperus spp., Parkinsonia aculeata, Prosopis spp., and Phoenix dactylifera were some of the frequent types. Amongst the fungal spores group Cladosporium, Smuts spores, Colored basidiospores, Alternaria, Ulocladium and Drechslera were the dominant types.  相似文献   
119.
Latent infection is one of the major problem encountered in plant tissue culture, with no effective solution available so far. It is responsible for huge losses in terms of time, effort and money both in industrial and scientific laboratories. In the present investigation, we have used copper sulfate (CuSO4) for effective control of latent infection in cultures of Erythrina variegata, without compromising on the growth of the culture. Culture media MS?+?BA (5.0 μM)?+?NAA (0.5 μM) were supplemented with different concentrations of CuSO4, among the evaluated concentrations, 10.0 μM was found to be most suitable. The adventitious shoots produced per explant, average shoot length and chlorophyll content, increased in cultures growing on optimized CuSO4, also, instances of endogenous infection were significantly reduced, but no signs of toxicity in plants could be detected. However, at higher concentration (>10 μM) of copper, albeit, infection was suppressed more effectively but the growth of plant was severely affected, recording significant reduction in numbers of shoots per explant, average shoot length and chlorophyll content. The results obtained demonstrate that copper optimization in plant tissue culture media provides twofold benefits; not only it improves the shoot multiplication rate and growth of the cultures, but, also effectively controls the problem of endogenous infection with no cytotoxicity.  相似文献   
120.
To date, publicly available plastid genomes of legumes have for the most part been limited to the subfamily Papilionoideae. Here we report 13 new plastid genomes of legumes spanning all three subfamilies. The genomes representing Caesalpinioideae and Mimosoideae are highly conserved in gene content and gene order, similar to the ancestral angiosperm genome organization. Genomes within the Papilionoideae, however, have reduced sizes due to deletions in nine intergenic spacers primarily in the large single copy region. Our study also indicates that rps16 has been independently lost at least five times in legumes, with additional gene and intron losses scattered among the papilionoids. Additionally, genera from two distinct lineages within the papilionoids, Lupinus and Robinia, have a parallel inversion of 36 and 39 kb, respectively. This parallel inversion is novel as it appears to be caused by a 29 bp repeat within two trnS genes. This repeat is present in all available legume plastid genomes indicating that there is the potential for this inversion to be present in more species. This case of a homoplasious inversion is also evidence that some inversion events may not be reliable phylogenetic markers.  相似文献   
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