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121.
Nora A. AlFaris Ghedeir M. Alshammari Jozaa Z. AlTamimi Lujain A. AlMousa Reham I. Alagal Nora M. AlKehayez Dalal H. Aljabryn Muneer M. Alsayadi Mohammed Abdo Yahya 《Saudi Journal of Biological Sciences》2022,29(1):640-649
Shrimp is a prevalent food in the Arabian Gulf that is known for its good sensory properties and high nutritional value. The aim of the present work was to assess the effects of diverse processing methods on the nutritional composition of shrimp and the antioxidant activity of shrimp powder. Shrimp (Penaeus semisulcatus) flesh was treated using four processes (salting, frying, grilling, and boiling), following which its macronutrient content, fatty acid profile, vitamins and mineral contents were measured. Also, the antioxidant activity of all shrimp powder extracts was assessed using the 2, 2 diphenyl 1 picrylhydrazyl (DPPH), linoleic acid oxidation inhibition, and reducing power methods. The results revealed that the fresh and processed shrimp flesh had significant nutritional value and the fresh and treated shrimp powders have high antioxidant activity, but the cooking processes have significant effects on the nutritional value and antioxidant activity of shrimp flesh. These effects were greater significantly in grilled shrimp followed by boiled shrimp and then fried shrimp. It is concluded that the high nutritional value and antioxidant activity of shrimp flesh make it an important food for nutritional health promotion for the community. 相似文献
122.
Immunomodulation by morphine and marijuana 总被引:2,自引:0,他引:2
The immunomodulatory effects of morphine and the active components of marijuana, particularly tetrahydrocannabinol, on various aspects of the host immune parameters include alterations in humoral, cell-mediated and innate immunity. Most studies have shown immunosuppressive effects due to use of these abused substances, although there are reports that they may not produce any deleterious effect and may even enhance some aspects of host immunity. They reduce resistance to cancer growth and microbial pathogens in animals. 相似文献
123.
Mahtab Jafarzade Nur Ain Yahya Fatemeh Shayesteh Gires Usup Asmat Ahmad 《Journal of microbiology (Seoul, Korea)》2013,51(3):373-379
This study was undertaken to investigate the influence of culture conditions and medium components on production of antibacterial compounds by Serratia sp. WPRA3 (JX020764) which was isolated from marine water of Port Dickson, Malaysia. Biochemical, morphological, and molecular characteristics suggested that the isolate is a new candidate of the Serratia sp. The isolate showed strong antimicrobial activity against fungi, Gram-negative and Gram-positive bacteria. This bacterium exhibited optimum antibacterial compounds production at 28°C, pH 7 and 200 rev/min aeration during 72 h of incubation period. Highest antibacterial activity was obtained when sodium chloride (2%), yeast extract (0.5%), and glucose concentration (0.75%) were used as salt, nitrogen, and carbon sources respectively. Different active fractions were obtained by Thin-Layer Chromatography (TLC) and Flash Column Chromatography (FCC) from ethyl acetate crude extracts namely OCE and RCE in different culture conditions, OCE (pH 5, 200 rev/min) and RCE (pH 7/without aeration). In conclusion, the results suggested different culture conditions have a significant impact on the types of secondary metabolites produced by the bacterium. 相似文献
124.
M. S. Salwa M. N. Nur Asshifa A. A. Amirul Ahmad R. M. Yahya 《Biotechnology and Bioprocess Engineering》2009,14(6):763-768
A locally-isolated Pseudomonas aeruginosa USM AR2 possessing the ability to produce glycolipid-type biosurfactant (rhamnolipid) was used in this research to explore
fermentation technology for rhamnolipid production. Rhamnolipid concentration in 2.5 L fed-batch fermentation was improved
from 0.173 to 8.06 g/L by manipulating the feeding strategy and cultivation protocol. The culture was fed with petroleum diesel
and complex medium. The highest rhamnolipid concentration was achieved when the culture was initially fed with both petroleum
diesel and complex medium, followed by feeding of petroleum diesel only at the end of the stationary phase. Severe foaming
problem was resolved by modifying and integrating a foam recycler to the bioreactor. This successfully extended the cultivation
period and increased the yield of final rhamnolipid. No antifoam agent was added as this modified bioreactor allowed cultivation
to proceed even under foam generation. The viscosity measurement, surface tension activity test, and drop-collapse test were
performed as an indirect measure of rhamnolipid presence. 相似文献
125.
Water and sediment samples were collected from 18 sampling stations in Wadi Gaza for two successive years in order to: (1)
Establish a baseline condition of the geochemistry of surface water and sediments; (2) assess the impact of seasonal variation
on distribution of heavy metals and major ions; and (3) identify possible natural and anthropogenic sources of pollution.
The heavy metal concentrations in the sediments of the lake (downstream) were higher than those of the eastern eight stations(upstream)
where the water was shallower. Shallower areas showed greater temporal variation than deeper areas. Several elements (P, Fe,
Mn and As) showed the greatest temporal variability. For example, in the winter rainy season these elements decreased 2–10
times compared to their values in summer. Moreover, Ca, Na, Cl, PO4, and NO3 decreased3, 3, 5, 2, 4 times, respectively. Some of the trace metals were more abundant in these waters compared to the domestic
wastewaters of the study area. The averages of Cd and Co were 6 and 43 μg/l, respectively and they were 50 times higher than
the domestic wastewater results. The discharge of olive oil mill wastewater was recorded in the Ca, Na, Mg, K and P concentrations
in sediments of one of the sampling stations. 相似文献
126.
El-Kattan Y Lin TH Wu M Kumar VS Kotian PL Ghosh A Cheng X Bantia S Babu YS Chand P 《Nucleosides, nucleotides & nucleic acids》2005,24(10-12):1597-1611
A number of N6-substituted 9-[3-(phosphonomethoxy)propyl]adenine derivatives having hydroxymethyl at C-1' position were prepared from the appropriate 6-chloroadenine derivative. The syntheses of the corresponding prodrugs of these compounds are also reported. These compounds showed poor activity against HCV in replicon assay. 相似文献
127.
OBJECTIVE: To describe the intraoperative crush preparation and the cytologic features of craniopharyngioma and the differential diagnosis. STUDY DESIGN: Twelve cases of craniopharyngioma were diagnosed by crush preparation cytology in the Department of Pathology, Shiraz Medical School, and formed the basis of this study. The patients' ages ranged from 7 to 43 years; 3 were female and 9 male. The cytologic findings together with the histologic findings were studied. RESULTS: All cases had a high yield of cells, consisting of honeycomb sheets of epithelial cells with and without palisading rows of cells, papillary clusters, squamous cell clusters, anucleated squames, calcification, multinucleated giant cells, cholesterol crystals, glandular or rosettelike structures, ciliated columnar cells and spindle cells. The smears were diagnosed as suggestive of craniopharyngioma. Histologic sections confirmed the cytologic diagnoses. CONCLUSION: Intraoperative cytologic crush preparation findings are helpful in the diagnosis of craniopharyngioma, when combined with clinical information. Crush preparation cytology is important in the diagnosis of central nervous system tumors. 相似文献
128.
Kumar PV Vasei M Daneshbod Y Zakerinia M Ramzi M Noorani H Bagheri H Talei AR Soleimanpour H 《Acta cytologica》2005,49(4):445-448
BACKGROUND: Multiple myeloma of the breast is very rare, and the fine needle aspiration (FNA) findings have not been reported before. CASES: Two cases of multiple myeloma presented with bilateral breast nodules during treatment with chemotherapy. One case of multiple myeloma presented initially with a left breast mass. FNA smears of all 3 cases revealed numerous plasma cells, plasmablasts and multinucleated giant plasma cells. The smears were diagnosed as plasma cell tumors. Serum immunoelectrophoresis revealed IgG myeloma in 2 cases and IgA myeloma in 1. Marrow aspirates revealed > 30% plasma cells. Two patients died, and 1 was alive at this writing. CONCLUSION: The aspiration cytology findings of myeloma can be confuse, with primary and secondary tumors of the breast. The previous clinical history and ancillary studies, such as bone marrow study and serum immunoelectrophoresis, are essential to the correct diagnosis. 相似文献
129.
Hypothesis: apo‐lactoferrin–Galantamine Proteo‐alkaloid Conjugate for Alzheimer's disease Intervention
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Yahya E. Choonara Priyamvada Pradeep Lisa C. du Toit Viness Pillay 《Journal of cellular and molecular medicine》2018,22(3):1957-1963
Alzheimer's disease (AD) is known to be caused by the accumulation of deformed beta amyloid and hyperphosphorylated tau proteins resulting into formation and aggregation of senile plaques and neurofibrillary tangles in the brain. Additionally, AD is associated with the accumulation of iron or metal ions in the brain which causes oxidative stress. Galantamine (Gal) is one of the therapeutic agents that has been approved for the treatment of AD, but still saddled with numerous side effects and could not address the issue of iron accumulation in the brain. The use of metal chelators to address the iron accumulation has not been successful due to toxicity and inability to address the aggregation of the plaques. We therefore hypothesize a combinatorial antioxidant–metal–chelator approach by formulating a single dosage form that has the ability to prevent the formation of free radicals, plaques and accumulation of iron in the brain. This can be achieved by conjugating Gal with apo‐lactoferrin (ApoLf), a natural compound that has high binding affinity for iron, to form an apo‐lactoferrin–galantamine proteo‐alkaloid conjugate (ApoLf–Gal) as a single dosage form for AD management. The conjugation is achieved through self‐assembly of ApoLf which results in encapsulation of Gal. ApoLf changes its conformational structure in the presence of iron; therefore, ApoLf–Gal is proposed to deliver Gal and pick up excess iron when in contact with iron. This strategy has the potential to proffer a dual neuroprotection and neurotherapeutic interventions for the management of AD. 相似文献
130.
Ester synthesis in lipase-catalyzed reactions 总被引:12,自引:0,他引:12
Ahmad R. M. Yahya William A. Anderson Murray Moo-Young 《Enzyme and microbial technology》1998,23(7-8):438-450
This review discusses the myriad of reaction systems employed in ester production catalyzed by lipases. Enzyme behavior in reaction systems is a consequence of certain structural patterns typical of lipases. Water has a profound effect on the lipase behavior either directly by affecting the hydration of the enzyme or indirectly by changing the nature of the reaction media and/or enzyme support materials. The significance of water is further emphasized with the understanding of its role in various reaction media and support materials. In addition to water, the media and support material are seldom inert and often interact with other factors affecting the reaction. Several methods of water removal and their effectiveness in lipase-catalyzed reactions are discussed. There is a recent surge of interest in modifying lipase systems with surfactants as studies demonstrate the potential of the enhanced performance of surfactant-modified lipases. 相似文献