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311.
Tarabees Reda Gafar Khaled M. EL-Sayed Mohamed S. Shehata Awad A. Ahmed Marwa 《Probiotics and antimicrobial proteins》2019,11(3):981-989
Probiotics and Antimicrobial Proteins - The current study conducted to investigate the effects of a multi-strain commercial probiotic mix and prebiotic (isomaltooligosaccharide, IMO) on broiler... 相似文献
312.
Gihan M. Tawfeek Hala S. Elwakil Nabil S. Awad Laila El-Hoseiny Hala S. Thabet Rania M. Sarhan Samar K. Darweesh Wagida A. Anwar 《The Korean journal of parasitology》2009,47(3):259-264
Genetic polymorphisms of encoding antigen B2 gene (AgB2) in Echinococcus granulosus were studied using PCR-RFLP and DNA sequencing among 20 Egyptian isolates. Five isolates from different host origins (humans, camels, pigs, and sheep) were collected and used. All examined isolates of each host group gave very similar patterns of PCR-RFLP after restriction enzyme digestion with AluI, with the gene size of approximately 140 bp and 240 bp for sheep and human isolates, and approximately 150 bp and 250 bp for pig and camel isolates. No digestion pattern was obtained after incubation of all studied isolates with EcoRI. These results reveal high intra-group homogeneity. DNA sequence analysis highlighted that human infecting strain showed 100% identity with respect to sheep infecting isolate, 96% and 99% with pig and camel infecting isolates, respectively. 相似文献
313.
Amany O. Kamel Gehanne A. S. Awad Ahmed S. Geneidi Nahed D. Mortada 《AAPS PharmSciTech》2009,10(4):1427-1436
A major cause of thromboplebitis, during acyclovir (ACV) parenteral administration is the high pH of its reconstituted solution
(pH 11). Its plasma half life is 2.5 h, requiring repeated administration which may result in excess of drug solubility leading
to possible renal damage and acute renal failure. The present study reports the efficiency of stealthy ACV nanoparticles (NPs)
to increase the mean residence time of the drug 29 times. It caused a marked decrease in thrombophlebitis when injected into
rabbit’s ear vein. The polymers used were (Poly lactic acid, polylactic-co-glycolic (PLGA) 85/15, PLGA 75/25, PLGA 50/50).
Particles were evaluated for their encapsulation efficiency, morphology, particle size and size distribution, zeta potential,
and in vitro drug release. Small NPs (280–300 nm) with 60% drug release after 48 h were obtained. Among the block copolymer used, poloxamer
407 was of superior coating properties with a coat thickness in the range of 1.5–8.3 nm and a decreased surface charge. 相似文献
314.
Awad O Yustein JT Shah P Gul N Katuri V O'Neill A Kong Y Brown ML Toretsky JA Loeb DM 《PloS one》2010,5(11):e13943
Background
Cancer stem cells are a chemotherapy-resistant population capable of self-renewal and of regenerating the bulk tumor, thereby causing relapse and patient death. Ewing''s sarcoma, the second most common form of bone tumor in adolescents and young adults, follows a clinical pattern consistent with the Cancer Stem Cell model – remission is easily achieved, even for patients with metastatic disease, but relapse remains frequent and is usually fatal.Methodology/Principal Findings
We have isolated a subpopulation of Ewing''s sarcoma cells, from both human cell lines and human xenografts grown in immune deficient mice, which express high aldehyde dehydrogenase (ALDHhigh) activity and are enriched for clonogenicity, sphere-formation, and tumor initiation. The ALDHhigh cells are resistant to chemotherapy in vitro, but this can be overcome by the ATP binding cassette transport protein inhibitor, verapamil. Importantly, these cells are not resistant to YK-4-279, a small molecule inhibitor of EWS-FLI1 that is selectively toxic to Ewing''s sarcoma cells both in vitro and in vivo.Conclusions/Significance
Ewing''s sarcoma contains an ALDHhigh stem-like population of chemotherapy-resistant cells that retain sensitivity to EWS-FLI1 inhibition. Inhibiting the EWS-FLI1 oncoprotein may prove to be an effective means of improving patient outcomes by targeting Ewing''s sarcoma stem cells that survive standard chemotherapy. 相似文献315.
Alfarazdeg A. Saad Nuha G. Ahmed Osman S. Osman Ahmed Almustafa Al-Basheer Awad Hamad Stijn Deborggraeve Philippe Büscher Gerard J. Schoone Henk D. Schallig Thierry Laurent Ahmed Haleem Omran F. Osman Ahmed Mohamedain Eltom Mustafa I. Elbashir Sayda El-Safi 《PLoS neglected tropical diseases》2010,4(8)
Background
The Leishmania OligoC-TesT and NASBA-Oligochromatography (OC) were recently developed for simplified and standardised molecular detection of Leishmania parasites in clinical specimens. We here present the phase II evaluation of both tests for diagnosis of visceral leishmaniasis (VL), cutaneous leishmaniasis (CL) and post kala-azar dermal leishmaniasis (PKDL) in Sudan.Methodology
The diagnostic accuracy of the tests was evaluated on 90 confirmed and 90 suspected VL cases, 7 confirmed and 8 suspected CL cases, 2 confirmed PKDL cases and 50 healthy endemic controls from Gedarif state and Khartoum state in Sudan.Principal Findings
The OligoC-TesT as well as the NASBA-OC showed a sensitivity of 96.8% (95% CI: 83.8%–99.4%) on lymph node aspirates and of 96.2% (95% CI: 89.4%–98.7%) on blood from the confirmed VL cases. The sensitivity on bone marrow was 96.9% (95% CI: 89.3%–99.1%) and 95.3% (95% CI: 87.1%–98.4%) for the OligoC-TesT and NASBA-OC, respectively. All confirmed CL and PKDL cases were positive with both tests. On the suspected VL cases, we observed a positive OligoC-TesT and NASBA-OC result in 37.1% (95% CI: 23.2%–53.7%) and 34.3% (95% CI: 20.8%–50.9%) on lymph, in 72.7% (95% CI: 55.8%–84.9%) and 63.6% (95% CI: 46.6%–77.8%) on bone marrow and in 76.9% (95% CI: 49.7%–91.8%) and 69.2% (95% CI: 42.4%–87.3%) on blood. Seven out of 8 CL suspected cases were positive with both tests. The specificity on the healthy endemic controls was 90% (95% CI: 78.6%–95.7%) for the OligoC-TesT and 100% (95% CI: 92.9%–100.0%) for the NASBA-OC test.Conclusions
Both tests showed high sensitivity on lymph, blood and tissue scrapings for diagnosis of VL, CL and PKDL in Sudan, but the specificity for clinical VL was significantly higher with NASBA-OC. 相似文献316.
Awad AB Toczek J Fink CS 《Prostaglandins, leukotrienes, and essential fatty acids》2004,70(6):511-520
Cardiovascular disease (CVD) remains the leading cause of death in Western societies. Atherosclerosis is a major cardiovascular related disorder that is responsible for 50% of all mortality in the United States. Several epidemiological studies suggest that consumption of a plant-based diet is associated with a decreased incidence of cardiovascular abnormalities. Phytosterols, especially beta-sitosterol, are plant sterols that have been shown to exert protective effects against cardiovascular diseases as well as many types of cancer. Monocyte/macrophage cells are involved with the inflammatory process. Accumulation of these cells in arteries is one of the initial events leading to atherosclerosis. Macrophages are capable of supplying the atherosclerotic vessel with substantial amounts of prostaglandins. Prostaglandins have been shown by numerous studies to play a key role in the atherosclerosis process. They can affect platelet aggregation, vasodilation or constriction of blood vessels, and the adherence of monocytes to the vessel walls. The purpose of this study was to examine the effect of phytosterols on the release of PGE(2) and PGI(2) from lipopolysaccharide (LPS)-stimulated P388D(1)/MAB macrophage cells. P388D(1)/MAB cells were supplemented with 16 microM cholesterol, beta-sitosterol or campesterol using cyclodextrin as a vehicle. Phytosterol supplementation led to a significant decrease in cellular growth at various time points throughout a 7-day treatment period, especially after 3 days of treatment. Macrophages incorporated the supplemented phytosterols into their membranes which accounted for 26% of total membrane sterols. Cholesterol supplementation at 16 microM however, had no effect on membrane sterols. Supplementation with 16 microM concentration of beta-sitosterol or campesterol resulted in a significant inhibition of PGE(2) and PGI(2) release from macrophage cells as compared to the vehicle control. Of the two phytosterols, beta-sitosterol supplementation exhibited a greater inhibitory effect. PGE(2) release was decreased 68% by beta-sitosterol and 55% by campesterol, while cholesterol supplementation was not as effective, as it led to a 37% decrease. Similarly, release of PGI(2) from macrophages was inhibited 67% by beta-sitosterol and 52% by campesterol treatment, while enrichment of the cells with cholesterol, led to a 35% decrease in PGI(2) release. The decrease in prostaglandin release was not due to alteration in the expression of cPLA(2) and COX-2 enzymes which suggests that alterations in the activities of these enzymes may be responsible for the observed changes in prostaglandin release. It was concluded that phytosterol incorporation into macrophages may offer protection from atherosclerosis by reducing their prostaglandin release and thus slowing down the atheroma development. 相似文献
317.
P M Bode T A Awad O Koizumi Y Nakashima C J Grimmelikhuijzen H R Bode 《Development (Cambridge, England)》1988,102(1):223-235
The head of a hydra is composed of two parts, a domed hypostome with a mouth at the top and a ring of tentacles below. When animals are decapitated a new head regenerates. During the process of regeneration the apical tip passes through a transient stage in which it exhibits tentacle-like characteristics before becoming a hypostome. This was determined from markers which appeared before morphogenesis took place. The first was a monoclonal antibody, TS-19, that specifically binds to the ectodermal epithelial cells of the tentacles. The second was an antiserum against the peptide Arg-Phe-amide (RFamide), which in the head of hydra is specific to the sensory cells of the hypostomal apex and the ganglion cells of the lower hypostome and tentacles. The TS-19 expression and the ganglion cells with RFamide-like immunoreactivity (RLI) arose first at the apex and spread radially. Once the tentacles began evaginating in a ring, both the TS-19 antigen and RLI+ ganglion cells gradually disappeared from the presumptive hypostome area and RLI+ sensory cells appeared at the apex. By tracking tissue movements during morphogenesis it became clear that the apical cap, in which these changes took place, did not undergo tissue turnover. The implications of this tentacle-like stage for patterning the two-part head are discussed. 相似文献
318.
O M Awad 《Chemico-biological interactions》1974,8(2):75-86
A carbohydrase is present in testicular tissue of normal rats, most being found in the soluble fraction of the tissue homogenate. The enzyme hydrolysed starch to maltose and maltotriose, indicating an endo-type amylase. It hydrolysed glycogen, but not maltose, isomaltose, panose and α-limit dextrins.Nitrofuranfuradroxyl, which causes spermatogenic arrest in the rat, inhibited the amylase activity of testicular tissue. In the seminiferous tubules, there was a decrease in the number of sperms and a gradual reduction in enzyme activity measured at early stages of spermatogenic arrest. Another abnormality was the formation of giant nuclei23. When the enzyme of the treated animals was incubated in vitro, it hydrolysed starch into glucose in addition to the two normal products. Inhibition was of the competitive type; at substrate concentrations below 35 the Km was changed from 1.25 · 10?4M for the untreated to 4.3 · 10?4M for the treated enzyme in vitro. The activity of the in vitro-treated and untreated enzymes was decreased by dialysis. Addition of calcium chloride restored the activity of the untreated enzyme only. The inhibition in vivo was reversed only weeks after the removal of the furadroxyl. 相似文献
319.
The fatty acyl group composition of Ehrlich ascites tumor cell plasma membranes was modified by feeding the tumor-bearing mice diets rich in either coconut or sunflower oil. When coconut oil was fed, the oleate content of the membrane phospholipids was elevated and the linoleate content reduced. The opposite occurred when sunflower oil was fed. Qualitatively similar changes were observed in the plasma membrane phosphatidylethanolamine, phosphatidylcholine and mixed phosphatidylserine plus phosphatidylinositol fractions. These diets also produced differences in the sphingomyelin fraction, particularly in the palmitic and nervonic acid contents. Unexpectedly, the saturated fatty acid content of the plasma membrane phospholipids was somewhat greater when the highly polyunsaturated sunflower oil was fed. The small quantities of neutral lipids contained in the plasma membrane exhibited changes in acyl group composition similar to those observed in the phospholipids. These fatty acyl group changes were not accompanied by any alteration in the cholesterol or phospholipid contents of the plasma membranes. Therefore, the lipid alterations produced in this experimental model system are confined to the membrane acyl groups. 相似文献
320.
Summary Kikuyu (Pennisetum clandestinium Hochst) grew relatively poorly on the Wollongbar krasnozem at soil pH values below 4.36. At these low pH values dry matter
yields were increased by raising the pH or by application of high rates of phosphate. Both treatments decreased the concentration
of soluble soil-Al on which the concentration of Al in tops was linearly dependent (r=0.95).
The inverse relationship found between plant growth and Al concentration, when present in excess of ∼1.5 μg/g soil and ∼90
μg/g tops, is suggestive of Al toxicity. However, at Al concentrations causing severe yield reductions, the Ca concentration
in kikuyu tops was approaching deficiency levels. The Al-Ca antagonism was further demonstrated by the reduction in Ca-uptake
caused by increased concentrations of soluble soil-Al under constant conditions of exchangeable Ca and of pH. The yield-reducing
effects of Al toxicity per se and Al-induced Ca deficiency are therefore confounded. 相似文献