Liposomal diltiazem HCl as ocular drug delivery system for glaucoma

In this study, unilamellar liposomal vesicles of diltiazem HCl (DH) were prepared using either reversed phase evaporation (REV) or proliposome methods. Soya phosphatidylcholine (SPC) was used for preparing the liposomes, and the vesicles were rigidified using cholesterol (Chol) or cetyl alcohol (CA) in different molarities. The major differences in both the entrapment efficiency percent (EE%) and drug release were evaluated as a function of the method of preparation, Chol or CA contents, and charging lipids. Moreover, the morphology of the vesicles was confirmed by transmission electron microscopy. The effects of Chol or CA incorporation into the liposomes were discussed based on thermal analysis. The in vivo evaluation of liposomal DH was assessed using intra-ocular pressure (IOP), reducing effects in rabbit eyes. Liposomes prepared via REV exhibited higher EE% and lower release rates when compared with those prepared from proliposomes. The incorporation of either Chol or CA in the liposomes enhanced the EE% and decreased the release rates; however, Chol yielded higher results than CA. In addition, both dicetyl phosphate (DCP; negative charge inducer) and stearyl amine (SA, positive charge inducer) decreased the EE% and increased the DH release rate. The in vivo antiglaucoma effects of the liposomes were calculated according to the area above the IOP/Time curve, the maximum response and the time for the maximum response and were compared with effects of the DH solution. The results were in the following order: DH solution?相似文献   

Economic evaluation of different scenarios for gas turbine waste heat recovery to produce water and power

In this study, economic analysis of different configurations of combined power and water systems is performed using DEEP software. Three different desalination systems including reverse osmosis (RO), multi-effect desalination (MED) and multi-stage flash (MSF) coupled to a gas turbine power plant with 2?×?165.1?MW capacity are considered and analysed. A specific capacity of 50,000?m³/day is assumed for all desalination systems. The results indicate that the RO system has the lowest simple payback time, while MED has the highest thermal utilisation. In terms of levelised cost of water, the RO system has the lowest amount with 1.03?$/(m³/day), while levelised cost of water for MED and MSF are equal to 1.47 and 1.93?$/(m³/day), respectively. Also sensitivity analysis showed that the fuel cost is the most effective parameter on the levelised cost of water. In general, it can be concluded that the RO system is the best choice in terms of economics.     

Environmental exposure of the pediatric age groups in Cairo City and its suburbs to cadmium pollution.

In a trial to assess the exposure of subjects in the pediatric age group to cadmium (Cd) pollution, serum Cd was estimated by atomic absorption spectrometry in 405 subjects, birth-18 years old, from Cairo City and its suburbs. Serum Cd mean concentrations were: 0.92 microg/l in 32 neonates (birth-4 weeks); 1.33 microg/l in 70 infants (4 weeks-2 years); 1.11 microg/l in 100 children in the preschool period (2-6 years); 1.34 microg/l in 103 primary school children (6-12 years); and 1.24 microg/l in 100 adolescents (12-18 years). In neonates, serum Cd was higher in babies with weights and heights that remained below the 5th percentile for age. Breast-fed infants had a serum Cd geometric mean level (1.25 microg/l) that was not in accordance to that of their mothers' milk (0.52 microg/l, P < 0.001), suggesting alternative routes of exposure. Environmental tobacco-smoke exposure was the most important determinant of Cd status in the school-aged children, the geometric mean being 1.42 microg/l in passive smokers vs. 1.2 microg/l in non-exposed children (P < 0.05). Moreover, adolescents who were active smokers had a significantly higher serum Cd level (1.7 microg/l) as compared to non-smokers (1.2 microg/l). Gender did influence the Cd status in adolescents, being higher among males, probably related to smoking, or to the difference in lifestyle of adolescents according to gender in the community. Alpha-1-microglobulinuria was accompanied by a higher serum Cd concentration in the group of adolescents only, suggesting a subclinical renal effect after several years of cumulative exposure. The residential classification, whether urban or suburban, did not influence the serum Cd status; neither did the present or past history of bronchial asthma. These findings certainly justify further evaluation of the problem of Cd pollution among Cairene individuals, knowing the long-term consequences of exposure to it. Systematic efforts for the proper disposal of Cd wastes and prevention of smoking in public places are recommended.     

Monoclonal antibody-based enzyme immunoassay for detection of porcine plasma in fish surimi

Detection of porcine plasma using indirect ELISA was developed using mAb B4E1 for the prevention of their usage in human food that creates religious and health conflicts. The immunoassay has a CV < 20% and did not cross-react to other meat and non-meat proteins. The sensitivity of the assay is 0.25% (w/w) of porcine plasma in spiked raw and cooked fish surimi. The assay did not produce a false positive result for any of the commercial fish surimi tested that were not contain porcine plasma. Determination of a 60-kDa antigenic protein of porcine blood using Western blot confirmed its presence in the plasma fraction of the porcine blood. Further proteomic analysis involving liquid chromatography–tandem mass spectrometry (LC-MS/MS) revealed the 60-kDa protein to be porcine serum albumin.     

Effect of different starter cultures on the biogenic amines production as a critical control point in fresh fermented sausages

The selection of critical control points is one of the most important steps in the design of a hazard analysis and critical control points system. In this study, the influence of starter culture inoculation on biogenic amine accumulation in fresh fermented sausage as critical control point was studied. The effect of three starter culture Lactobacillus plantarum plus Bifidobacterium lactis, L. plantarum plus Bifidobacterium bifidum or L. plantarum plus B. lactis and B. bifidum on amines production were investigated. Tyramine (TY), Cadaverine (CA), Putrescine (PU), Histamine (HIS) and Tryptamine (TR) contents increased during the fermentation and storage stage, and TY was the prevailing amine in the final product. Sausages produced by fermentation with starters, as compared to natural fermentation (control), had a lower amount of biogenic amine. A great reduction in biogenic amine content was achieved when Bifidobacterium sp. were inoculated, also levels of species of Enterobacteriaceae and Pseudomonas decreased, while lactic acid bacteria counts increased during fermentation and storage.     

Volatile compounds characterising Tunisian virgin olive oils: the influence of cultivar

In this work, the volatile profiles of four Tunisian virgin olive oils were established by headspace‐solid phase microextraction and gas chromatography, using flame ionisation and mass spectrometer detectors. More than eighty compounds were isolated and characterised, representing 97–99% of the total GC area. The main volatile compounds present in the oil samples were determined quantitatively, the major constituents were often aldehydes, particularly (E)‐2‐hexenal (48–90%). Significant differences in the content of volatile constituents were observed. These quantitative differences were used to distinguish between virgin olive oils from different varieties.     

Comparison of gene nature used in real-time PCR for porcine identification and quantification: A review

Pork adulteration has been a major concern nowadays for Halal verification. Unintentional pork inclusion by contamination in highly processed food materials involves a minute amount of porcine DNA to be detected, emphasizing the need of specific and sensitive method for porcine detection. Real-time PCR is a widely used technique for species identification that can serve this purpose besides providing a powerful quantification method. Incorporation of a highly sensitive and specific probe can greatly improve the specificity and sensitivity of the assay. However, derivation of PCR primers, either from nuclear DNA (nDNA) or mitochondrial DNA (mtDNA) can relatively affect the sensitivity and specificity of the reaction as well as the quantitative measurement. In this review, both types of DNA are compared in terms of their characteristics and their influence on species identification and quantification using real-time PCR.     

Salt effect on phenolics and antioxidant activities of Tunisian and Canadian sweet marjoram (Origanum majorana L.) shoots

BACKGROUND: Two varieties of Origanum majorana (Canadian and Tunisian) were evaluated for their phenolic, flavonoid and tannin contents, individual phenolic compounds and antioxidant activities under NaCl constraint. RESULTS: The results showed a significant variability in phenolic composition and antioxidant behavior between the two varieties under salt stress. The phenolic composition of methanolic extracts was determined by reversed‐phase high‐performance liquid chromatography. Amentoflavone was the predominant flavonoid compound; in addition, trans‐2‐hydrocinnamic acid became the major phenolic acid with salt treatment of the Tunisian variety. In the control, Canadian variety extract was characterized by high levels of gallic acid and amentoflavone. However, under 75 mmol L^?1 NaCl, gallic acid content doubled, whereas amentoflavone content was maintained in the Canadian variety. Stimulation of phenolic acid biosynthesis was observed in these two varieties under salt treatment despite the fact that shoots of the Tunisian variety showed higher antioxidant activities compared to those from the Canadian variety. Tunisian O. majorana might have developed tolerance to salinity and avoided tissue damage by activating enzymes involved in the galactosylation of quercetin into quercetin‐3‐galactoside and quercetin‐3‐rhamnoside. CONCLUSION: Our results confirmed the tolerance of Tunisian O. majorana plants. Copyright © 2012 Society of Chemical Industry