321 research outputs found
Developing monitoring system for long-distance pipeline leakage incorporating fusion of conflicting evidences
When transporting petroleum products, the use of long-distance pipelines have become
commonplace, due to their inherent efficiency and economy. However, such pipe systems often leak due
to corrosion, natural destruction, and, natural aging and weathering, causing harm to the environment,
fire etc. The ability to detect leakage with certainty and quickly is therefore very important. In this work,
leakage is detected using a combination of a hydraulic method and Dezert-Smarandache theory
Hydrographical conditions and benthic assemblages in the Suez Gulf, Egypt
The coastal development and human activities along the Suez Gulf leading
to sedimentation, degrade the quality of water, disturbing the natural structure and functions of aquatic communities. The Suez Gulf is a large semi-closed area with a 346 km long coastline on the western beach side. The prevailing physicochemical parameters in shallow intertidal waters were measured seasonally over the year. Benthic faunas in the sampling sites were studied indicating their regional distribution in relation to the impact of different environmental parameters in the intertidal region. The concentration of copper in seawater reached high level at St. IV (4.57 ug/1), which is exposed to sewage and petroleum hydrocarbons. The grain size of the sediment is a determining factor for the organic carbon concentration and the sandy substrate enhances organic matter degradation processes. A large number of oil fields are present along the western coast of the Suez
Gulf, therefore, cadmium and organic matter appeared to be high. The values of pH did not vary greatly among the different sampling sites. It was high at EI-Ein, El-Sukhna and Ras-Shukeir due to the disposal of mainly acidic sewage and industrial effluents of the two stations Adabiya and Ras-Gharib respectively. The macrobenthos included 71 species embraced mainly from Mollusca (53.5% Gastropoda and 12.7% Bivalvia) and the other
invertebrates included 7 groups namely, Rhizostoma, Polychaeta, Cirripedia, Amphipoda, Isopoda, Decapoda and Echinodermata. The distribution of benthos is affected by the temperature and salinity of seawater. The concentration of organic matter in seawater and in sediments in shallow waters shows high values in the central part of the Gulf of Suez
Impacts of environmental conditions on macrobenthic distribution along the Suez Gulf, Egypt
Increases in coastal development and human activities leading to sedimentation degrade the quality of water; disturb the natural structure and functions of aquatic communities. The Suez Gulf is a large semi-closed area (~625 km long coastline).The assemblages of bottom fauna were studied qualitatively and quantitatively in the shallow intertidal waters along the western coast of the Suez Gulf. The quality of seawater and sediment structures were analyzed. The distribution of macro-benthos included a total of 38 species of Gastropoda and 9 Bivalvia; and 25 species from the other invertebrates included 7 groups namely, Rhizostoma, Polychaeta, Cirripedia, Amphipoda, Isopoda, Decapoda and Echinodermata. The most dominant group among invertebrate groups was the Polychaeta which included 4 species: Hydroides elegans, Perinereis cultilifera, Perinereis nuntia and Ophelina acuminata. The Cirripedia were represented by 3 species namely, Balanus amphitrite, Chithamalus challengeri and Tetraclita squamosa. The variations in the numerical abundance and biomass of bottom fauna studied between the observation periods and at sampling sites. There was a marked increase in benthos biomass at St. IV (Ras Gharib) yielding an average of 318.8 g/m² in which the gastropod community represented the dominant species in collected samples reaching 270.28 g/m² (84.4% of the total biomass) and numerically numbered 116 ind./m². Veliger larvae of bivalves and gastropods appeared to be present in the plankton for long periods and their production seems to be continuous throughout the year. In the intertidal zone of the Suez Gulf, the values of pH varied within narrow limits. Water temperature and salinity seemed to be important in the distribution and abundance of the macro-benthos communities in the study areas. The organic content in shallow intertidal waters and sediments indicated high values in the central part of the Gulf of Suez
Utjecaj osteogeničnih dodataka agregatu mineralnog trioksida na razinu genske ekspresije odontoblastičnih markera nakon zatvaranja pulpe u pasa.
This study investigates the effect of addition of dexamethasone, vitamin D3, or chitosan to mineral trioxide aggregate (MTA) on the gene expression level of dentin sialophosphoprotein (DSPP) and matrix extracellular phosphoglycoprotein (MEPE) after pulp capping in dogs. Pulp exposure was performed in sixty dogs’ teeth. The teeth were classified into 3 equal groups according to the evaluation period. Group 1:7 days, group 2: 21 days and group 3: 60 days. Each group was further subdivided according to the pulp capping material used, into subgroup A: MTA + dexamethasone, subgroup B: MTA + dexamethasone + vitamin D3, subgroup C: MTA + chitosan and subgroup D: MTA. According to the group, the pulps of the capped teeth were removed for analysis of the relative mRNA expression level of DSPP and MEPE using PCR. Statistical analysis of all data was performed. In subgroup A, significant expression was observed of DSPP (P≤0.05) in group 2 up to 18.8 relative fold change while in subgroup B a significant upregulated gene expression of DSPP (P≤0.05) up to 29.4 relative fold change was seen. Significant upregulated DSPP expression (P≤0.05) was recorded in groups 1 and 2 up to 6.9 and 3.6 relative fold change, respectively in subgroup C. In conclusion, dexamethasone, with or without vitamin D3 and chitosan, are synergistic odontogenic inducers with MTA for differentiation of dental pulp cells in dogs. The upregulation of DSPP is a good marker for this differentiation.Istraživan je utjecaj dodatka deksametazona, vitamina D3 ili hitozana agregatu mineralnog trioksida na razinu ekspresije gena za dentin-sijalofosfoprotein (DSPP) i gena za ekstracelularni matriks fosfoglikoprotein nakon zatvaranja pulpe u pasa. Pulpa je bila otvorena na 60 zuba. Ti su zubi bili razvrstani u tri jednake skupine ovisno o trajanju promatranja. Prva skupina bila je promatrana sedam dana, druga skupina 21 dan, a treća skupina 60 dana. Svaka skupina bila je podijeljena u podskupine ovisno o materijalu rabljenom za zatvaranje pulpe. Podskupini A bio je primijenjen agregat mineralnog trioksida + deksametazon, podskupini B bio je primijenjen agregat mineralnog trioksida + deksametazon + vitamin D3, podskupini C agregat mineralnog trioksida + hitozan, a podskupini D samo agregat mineralnog trioksida. Sukladno skupinama, pulpe zatvorenih zuba bile su uzete za analizu relativne ekspresije mRNA za dentin-sijalofosfoprotein i za ekstracelularni matriks fosfoglikoprotein PCR-om. Svi podatci bili su statistički obrađeni. Značajna ekspresija gena za dentinsijalofosfoprotein (P≤0,05) bila je dokazana u podskupini A druge skupine u relativnoj vrijednosti 18,8, dok je u podskupini B značajna ekspresija gena za dentin-sijalofosfoprotein (P≤0,05) bila 29,4 puta veća. Značajno povećana ekspresija DSPP (P≤0,05) u prvoj i drugoj skupini sve do 6,9 odnosno 3,6 puta ustanovljena je u podskupini C. Može se zaključiti da deksametazon (s vitaminom D3 ili bez njega) i hitozan djeluju sinergistički s agregatom mineralnog trioksida kao odontogenični pokretači za diferencijaciju stanica zubne pulpe u pasa. Povećana razina dentin-sijalofosfoproteina dobar je pokazatelj te diferencijacije
COMPARATIVE IN VITRO DISSOLUTION STUDY ON METFORMIN MARKET PRODUCTS USING DIFFERENT DISSOLUTION APPARATUSES
Objective: This study was proposed to evaluate and compare the in vitro dissolution profiles of six Metformin Hydrochloride (MH) market products.
Methods: Different dissolution apparatuses (USP apparatus II, IV and beaker method) were used to evaluate the dissolution profiles (in phosphate buffer, pH 6.8) of two immediate release (IR) generic products of Metformin Hydrochloride (MH): Cidophage® 1000 mg (G1, Egyptian market) and Metformin arrow® 1000 mg (G2, French market) with respect to the reference products named Glucophage® 850 mg (R1, Egyptian market and R2, French market). In addition to a generic controlled-release (CR) product; Cidophage Retard® 850 mg (G3) versus the reference product; Glucophage XR® 1000 mg (R3) (both from Egyptian market). Dissolution efficiency (D. E.) and the similarity factor (f2) were calculated. Weight uniformity, hardness, tablet dimensions and MH content were measured.
Results: Results of the three apparatuses showed that MH IR products studied (reference and generics) did not meet the 75% USP 30 specifications for MH dissolved at 30 min. For MH CR products, Glucophage XR® did not fulfill the USP release criteria, while Cidophage Retard® did. USP apparatus IV revealed the highest sensitivity and discriminative capability.
Conclusion: Generally, MH IR generics (G1 and G2) might be interchangeable with the innovator product (Glucophage®). However, Cidophage Retard® might not be interchangeable with Glucophage XR®
Occult hepatitis B infection in egyptian chronic hepatitis C patients: prevalence, impact on pegylated interferon/ribavirin therapy
PREPARATION AND EVALUATION OF METRONIDAZOLE SUSTAINED RELEASE FLOATING TABLETS
Objective: The objective of the present study is the preparation of metronidazole (MZ) floating tablets that are designed to retain in the stomach for a long time for better eradication of Helicobacter Pylori (H. pylori), a main cause of peptic ulcer disease.
Methods: Synthetic and natural polymers were studied for their floating potential in the presence of sodium bicarbonate, namely: hydroxypropyl methylcellulose (HPMC), carbopol 974P, sodium alginate{low and medium viscosity (LV & MV) grades}, locust gum and guar gum. Hardness, floating ability, release profiles and kinetics as well as DSC / FT-IR were studied.
Results: Results of both DSC and FT-IR spectroscopy revealed that there was no interaction between the drug and any of the proposed polymers. Carbopol 974P based tablets showed an unacceptable floating lag time (2 h) and did not maintain good tablet integrity. All other formulas were able to float after few seconds and showed buoyancy for more than 24 h. Meanwhile, sustained profiles of MZ release were obtained. After 6 h the amount of MZ released were: 75.11 %, 61.26 %, 54.56 %, 54.25 % and 43.42 % from sodium alginate-LV, HPMC-K4M, guar gum, locust gum and sodium alginate-MV based tablets, respectively. Kinetically, among the 5 assessed models, the release pattern of MZ from the tablets fitted best to Zero order and Hixson & Crowell Cube-Root models.
Conclusion: These stomach targeted dosage forms could maintain the minimum inhibitory concentration for sufficient time to allow for local eradication and thereby achieve better efficiency of therapy with improved patient compliance, reduced costs and minimized side effects caused by immediate release dosage forms
IN VITRO EVALUATION OF IBUPROFEN HOT-MELT EXTRUDED PELLETS EMPLOYING DIFFERENT DESIGNS OF THE FLOW THROUGH CELL
Objective: Hot-melt extrusion technique (HME) was used to prepare a sustained release (SR) multiparticulate oral dosage form (pellets) containing Ibuprofen (IBU). Prepared IBU-HME pellets were in vitro evaluated by flow-through cell dissolution tester (FTC, USP Apparatus #4) using different flow conditions and FTC designs.
Methods: In this study, Sucroester®WE15 was used as the polymeric carrier to prepare two different IBU loadings (60 % and 30 % w/w). In order to optimize the FTC conditions, different cell sizes, pellets loading and hydrodynamic conditions of FTC on IBU release rate from pellets were proposed.
Results: The results showed that the IBU release rate was increased in the larger cell than the small cell. In addition, laminar flow showed more reproducible results than turbulent flow. It was found that the large cell with laminar flow rate and homogeneous mixing of the pellets with glass beads was the optimum conditions for in vitro evaluation of these preparations.
Conclusion: Improper methods of sample loading as well as cell size may result in confusing or erroneous data if not analyzed carefully. Therefore, it might be critical to choose a specific cell design of the FTC for in vitro evaluation of pellets to obtain reliable and discriminative results reflecting the major as well as minor formulation variables
IN-VITRO DISSOLUTION STUDY OF MELOXICAM IMMEDIATE RELEASE PRODUCTS USING FLOW THROUGH CELL (USP APPARATUS 4) UNDER DIFFERENT OPERATIONAL CONDITIONS
Objective: To evaluate and compare the in-vitro dissolution profiles of five generic immediate release (IR) products of Meloxicam (MX) available in Egyptian market with the innovator reference product (Mobic®, R) using different operational conditions of the flow through dissolution cell (FTC, USP Apparatus 4), in phosphate buffer (pH=7.5).
Methods: The comparative in-vitro dissolution studies were performed under different FTC operational conditions such as cell size, tablet position within the cell, open and closed loops setup and type of flow (laminar and turbulent) on MX dissolution rate from different IR products.
Results: The study showed that two generic products, out of five, gave similar dissolution profiles with R using a specified well controlled condition of FTC. A selected generic product (Mobitil, G1) was tested versus R under different operational conditions of the FTC such as cell size, type of flow, tablet position and open & closed loops setup. The dissolution profile of MX from R was highly affected by changing the tablet position, slightly affected by the open & closed loops setup and not affected by cell size and type of flow. On the other hand, the dissolution profile of MX from G1 was affected by all the previous operational conditions. Comparing Æ’2 values between G1 against R among the different operational conditions proposed, only one in-vitro dissolution test showed similar dissolution profile of G1 with respect to R.
Conclusion: Three generic products of MX might not be interchangeable with the innovator product (Mobic®)
Evaluation of Homocysteine, Folic Acid and Vitamin B12 Levels among Egyptian Children with Idiopathic Epilepsy
Objective: To evaluate relationship between homocysteine (Hcy), folic acid and vitamin B12 with anti-epileptic drugs in epileptic patients and their role in epilepsy control.Patient and Methods: The study included 60 patients with idiopathic epilepsy and thirty non-epileptic children of the same age and sex served as controls. All cases were subjected to physical and neurological examination and electroencephalogram (EEG). Serum level of folic acid, homocysteine (Hcy) and vitamin B12 were done for both epileptic patients and controls. Non parametric test, one way ANOVA and Pearson’s correlation were used for analysis of data.Result: 44 patients (73.3%) had generalized epilepsy and the remaining patients had partial epilepsy (simple or complex). 37 patients (61.6%) were in grade I, 3 patients (5 %) were in grade II and the remaining 20 patients (33.3 %) were in grade III epilepsy. Vitamin B12 was significantly higher in epileptic patients. Duration of anti-epileptic drug treatment was correlated significantly to folic acid and Hcy level.Conclusion: antiepileptic drugs might upset the homeostatic balance of Hcy and its cofactors and cause abnormalities of their serum levels. The duration of anti-epileptic drug treatment was related to decrease of folic acid and increase in homocysteine levels
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