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1. Cytochrome P450 1A as a Biomarker of Benzo-a-Pyrene Pollution in
No full textInduction of ethoxyresorufin-O-deethylase (EROD) activity and cytochrome P450 1A (CYP1A) expression was used as a biomarker to assess the effect of waterborne exposure to Benzo-a- pyrene (B-a-P) Oreochromis niloticus and Pangasias sutchi. Both species were separately exposed, to three doses of B-a-P (0.01, 0.1 and 1 mg/L) at six different exposure times (6, 12, 24, 48, 72 and 96 hours). Enzyme activity and protein content were measured fluorimetrically in the hepatic S9 fraction. The response appeared as early as 6 hours post exposure. Both dose and time dependant response was observed in the EROD activity, being significantly higher at 48 hours for Oreochromis niloticus and at 12 hours for Pangasias sutchi, post exposure to 1mg /L. A similar response was observed in the CYP1A content in Pangasias sutchi, however, only a dose dependant response was detected in Oreochromis niloticus. Both groups showed higher values of EROD activity as compared to the CYP1A content, being higher in Pangasias sutchi. Our results show that hepatic CYP1A expression in terms of induction of EROD activity shows promise as a biomarker of organic contamination in the aquatic environment. Nevertheless, the work could be extended to assess the species specific response.1-Deanship of Scientific Research 2- Zoology department
Cadmium Bioaccumulation and Toxicity in Tilapia Fish (Oreochromis niloticus)
No full textThe present study was undertaken to determine the bioaccumulation of cadmium in livers of tilapia fish (Oreochromis niloticus) and to assess the histological alteration of intestine, liver and kidney tissues due to cadmium toxicity. Fish (Oreochromis niloticus) were exposed to cadmium at different concentrations (5 mg/l and 10 mg/l) for 7 days. Cadmium assayed by using AA220FS atomic absorption spectrophotometry. The concentration of Cadmium in the liver tissues in the fish exposed to 10 mg/l was found to be (9.09±0.51 μg/g dry wt) while it was 5.17±0.25 μg/g dry wt in the fish exposed to 5 mg/l. There was a significant increase of cadmium chloride concentration in the liver tissues of the fish exposed to 10 mg/l compared to the those exposed to 5 mg/l. Histological alterations on liver tissues were in the form severe fatty vacuolations, generalised necrosis of hepatocytes, fatty change, congestion of liver sinusoids and central veins. Intestines showed severe congestion of submucosal blood vessels and sloughing of mucosal epithelium. Kidneys showed severe glumerular shrinkage and necrosis, lymphocytic infiltration in the distal renal convoluted tubules. Histopathological changes were more pronounced in fish exposed to 10 mg/l cadmium chloride
The Protective Role of Selenium and Vitamins A, E, and C Against the Genotoxicity Induced by Sunset Yellow in Male Mice
No full textThe aim of the present work was to evaluate the protective role of selenium and vitamin A, C and E (Selenium ACE) concerning the reduction of the genotoxic effects induced by sunset yellow in mice using different mutagenic end points and their effects on DNA. The study included: its effect on the induction of sister chromatid exchanges (SCE’s) in bone-marrow cells, chromosomal aberration analysis in somatic (bone-marrow) and germ cells (spermatocytes) after single and repeated oral treatment, the induction of morphological sperm abnormalities in male mice and its effect on. The results showed genotoxic effects of sunset yellow as indicated increasing the frequency of SCE’s and chromosomal aberrations in both somatic and germ cells and increased morphological sperm abnormalities and DNA fragmentation. The results indicated also that the oral adminstration of selenium ACE significantly reduced the genotoxic effect induced by sunset yellow which open the field for using these antioxidants mix as chemopreventive agents in many applications
Effects of using rosemary volatile oil for weight gain reduction in rats.
No full textObesity is a major health problem world-wide. Medical interventions used for weight reduction proved to have side effects which might be dangerous for human health. The current trend is to use plant essential oils as a safer natural alternative that were found to have favourable effects e.g. as antioxidants.
In the present study, the effects of rosemary essential oils in reducing body weight were studied and also the major components of the volatile oil were identified using GC-MS analysis. During the 45 days experimental period, rats were divided into 3 groups, fed a diet containing 15% cottonseed oil that was either fresh oil (G1) or heated oil (G2) or heated oil mixed with 0.2% Rosemary essential oil (G3).
The parameters examined for studying the health effects of the rosemary oil were body weight gain, food intake, Food efficiency (FE),Protein efficiency ratio (PER) andOrgans weights, Haematological indices were measured in blood samples include assessing Hemoglobin, hematocrite, red blood cells (RBC), total leucocytes count (TLC) and leucocytes deferential , Serum glucose , Serum total bilirubin, and also lipid profiles .
The results showed that the weight gain for G2 was 119.57% and 90.35%for G3 compared to G1. Same pattern of effect was observed for food intake, which was found to be 12.5, 16.6 and 10.5 gm/day for G1, G2 and G3 respectivel
Isolation of antimicrobial peptides from Apis florae and Apis carnica in Saudi Arabia and investigation of the antimicrobial properties of natural honey samples
No full textAs part of the ongoing search for novel antimicrobial agents and their use in singular or
combined drug therapy, peptide fractions of molecular weights about 14.500 and 15.00 kDa were
isolated from the hemolymph of wild (Apis florae) and carniolan (Apis carnica) bees of Saudi Arabia
obtained from different regions in Riyadh (variable plant sources) during the honey seasons (spring
and summer) 2008–2009. Following experimental infection with 1.1 • l06 viable Escherichia coli cells
(ATCC 25922), the antimicrobial peptides were purified to homogeneity by reversed-phase high
performance liquid chromatography. Antibacterial activity of the isolated peptide was evaluated
in vitro by an agar well diffusion method for E. coli strain (ATCC 25922) and Klebsiella pneumoniae
strain (ATCC 11678), the major Gram negative pathogens causing urinary tract infections, and
Staphylococcus aureus (ATCC 6538) as Gram positive bacteria. A total of 10 honey samples collected from bee hives selected arbitrary at different floral areas of south Riyadh were also investigated for their antimicrobial activities against the yeast, Candida albicans (ATCC 10231) and four standard bacteria strains, E. coli (ATCC 25922), Pseudomonas aeruginosa (ATCC 27853), S. aureus (ATCC 6538) and Bacillus subtilis (ATCC 6633) using standard antimicrobial assays. The isolated antibacterial peptides and the different honey samples revealed comparable marked variations in antimicrobial activities and their sensitivity might be depending on their variable floral sources.King Saud Universit
Synthesis, radiochemical and biological characteristics of 99mTc-8-hydroxy-7-substituted quinoline complex: a novel agent for infection imaging
No full text2,2-[(8-hydroxyquinolin-7-yl)methylazanediyl] diacetic acid (HQMADA) was synthesized via reaction of 8-hydroxyquinoline with iminodiacetic acid in presence of paraformaldehyde with a yield of 27%. The obtained compound was well characterized via different analytical techniques. Labeling of the synthesized compound with technetium-99m in pertechnetate form (99mTcO4-) in the presence of stannous chloride dihydrate was carried out via chelation reaction. The reaction parameters that affect the labeling yield such as HQMADA concentration, stannous chloride dihydrate concentration, pH of the reaction mixture, and reaction time were studied to optimize the labeling conditions. Maximum radiochemical yield of 99mTc-HQMADA complex (91.9%) was obtained by using 1.5 mg HQMADA, 50 lg SnCl2_2H2O, pH 8 and 30 min reaction time. Biodistribution studies in mice were carried out in experimentally induced infection in the left thigh using E. coli. 99mTc-HQMADA complex showed higher uptake (T/NT = 5.5 ± 0.3) in the infectious lesion than the commercially
available 99mTc-ciprofloxacin (T/NT = 3.8 ±0.8). Biodistribution studies for 99mTc-HQMADA complex in Albino mice bearing septic and aseptic inflammation models showed that 99mTc-HQMADA complex able to differentiate between septic and aseptic inflammation.King Saud Universit
كتاب(أساسيات التحرير وفن الكتابة بالعربية)
No full textيضم هذا الكتاب عشرة فصول ، هي :
1- اللفظة : تعريف، الجانب البنائي، البعد الصوتي، اللفظة بين العربية والعجمة، اللفظة بين الفصحى والعامية، اللفظة والمعجم اللغوي .
2- الإملاء:الهمزة، التاء المربوطة، الألف اللينة، تنوين النصب، زيادة الحروف وحذفها في الكلمات، الوصل والفصل في الكلمات،الفرق بين الضاد والظاء.
3- الجملة: تأليف الجملة ، دلالة الجملتين الاسمية والفعلية، الجملة الخبرية والجملة الإنشائية، المساواة والإيجاز والإطناب، عيوب الجملة ، تدريبات .
4- أساسيات النحو: أقسام الكلمة، المعرب والمبني، أنواع الإعراب وعلاماته، الأسماء الخمسة، المثنى، جمع المذكر السالم، جمع المؤنث السالم ن الممنوع من الصرف، إعراب الفعل المضارع،الأفعال الناسخة، الحروف الناسخة، العدد وتمييزه.
5- أخطاء شائعة: تعريف الأخطاء اللغوية الشائعة، أخطاء كتابية ( إملائية) ، أخطاء نحوية ( تركيبية وإعرابية)، أخطاء صرفية اشتقاقية، أخطاء أسلوبية.
6- تمارين عامة: أحد عشر تمريناً .
7- كتابة الفقرة:تعريفها، شكلها، حجمها،أنواع الجمل وبناؤها في الفقرة، الروابط، نماذج وتطبيقات .
8- علامات الترقيم: تعريف الترقيم وأهميته، مواضع استعمال علامات الترقيم، تدريبات.
9- كتابة المقالة: تعريفها، خطوات كتابتها، شروط المقالة الجيدة، نماذج وتطبيقات.
10- الكتابة الوظيفية: كتابة التلخيص والخلاصة، كتابة الرسالة الإدارية
Application of Mixing Torque Rheometer in studying factors affecting the wet massing process and characteristics of the produced granules
No full textMastersOver 50 years of research in granulation technology, whoever more researches are required to elucidate this widely applicable technology. Binder selection for particular system is quite often empirical and dependent on the skills and experience of the formulator. Hand squeeze test was and still the main way for determination of wet granulation end point. It depends mainly on operator experience, so it is not possible to be validated. Literature reveals a variety of advanced monitoring techniques following up different stages of wet massing. Torque measurement has been proved to be the most reliable control method as its tight relation to mass resistance.
The first objective of this work was to investigate and optimize the influence of different variables on Hydroxypropyl methylcellulose binder solutions used as granulating agents during wet massing techniques prior to granulation step. Variables examined were the effect of polymer concentration, viscosity, addition of surfactant (Tween 80), addition of plasticizer (PEG 600), binder solution pH, and polymer grade. Mixing torque rheometer (MTR) was efficient in tracing and follow up of the interaction between liquid binder and the solid substrate providing us with the mean line torque of the wet mass and the optimum binder ratio required. The type of solid substrate (microcrystalline cellulose; Avicel PH-101) was kept constant while variation in the liquid binder grade and/or characteristics was tested. Full factorial design was used to study the possibility of combining more than one variable simultaneously on the same binder solution. Analysis of variance (ANOVA) was used for testing the significance of results. It was found that all HPMC concentrations were able to produce a mean line torque higher than that of the blank test. Increasing polymer molecular weight, concentration and/or viscosity caused increase in torque value of wet mass. The results showed the enhanced effect of plasticizer and surfactant on the spreading and diffusion of liquid binder inside solid substrate particles. The maximum torque amplitude of the wet mass was achieved using solution pH of about 7.5 and addition of 2.0 %v/v of surfactant.
The second objective of this work was to investigate and optimize the influence of different variables the torque profile of Carbopol and Polyvinylpyrrolidone. Variables examined were the effect of polymer concentration, viscosity, addition of surfactant (Tween 80), addition of plasticizer (PEG 600), binder solution pH, and polymer grade. It has been found that the maximum torque of the wet mass was achieved with Carbopol and Polyvinylpyrrolidone when adding 4.2 and 1.0 % v/v of plasticizer as well as 3.5 and 4.5 % v/v of surfactant, respectively.
The third objective of the current study was to study the effect of variations in the solid substrate particle size and composition on the rheological behavior of wet massing. This was done using three different liquid binders (Carbopol, Hydroxypropyl methylcellulose and Polyvinylpyrrolidone). Extrusion-spheronization was based upon the rheological data followed be evaluation of the produced pellets. A mixer torque rheometer (MTR) methodology was used for selecting the optimum binder volume which is suitable for wet massing and consequently for extrusion-spheronization. Different methods for pellets evaluation and assessing of quality were used such as scanning electron microscopy. Theophylline as a model drug was used for the current study. Statistical analysis was performed using one way ANOVA from which differences between formulations were considered to be significant at p ≤ 0.05. The results indicated that addition of any of the used co-excipient caused marked decrease in the maximum torque value below that of MCC alone. The influence of particle size on the dissolution behavior was of low effect while the type of the binder solution was more pronounced.
Last but not least the final objective of the current study was to figure out the influence of MTR instrumental variables on the pellets quality and performance. The current study also compared between hand-made granules and pellets using wet granulation. In addition a formula composed of Avicel PH-101 and dibasic calcium phosphate (90:10 % w/w) was selected for studying the ability to scale up and possibility of transfer form MTR to larger mixer types. It has been shown that. The hand-made granules showed the faster drug release within 20 minutes which may be related to their non compacted nature and higher porosity. The maximum torque was directly proportional to the mixing speed (rpm) value of MTR rotating blades. Pellets made of binder solution volume constituting the maximum torque position were of high quality. It has been shown that increasing binder volume led to decreasing friability of pellets and hand-made
granules. Results showed that increasing binder volume during wet massing led to decreased pellets particle size and decreased friability. The decreased flowability of hand-made granules may be attributed to the scaly nature of their morphology which might increase the friction to each other. Scaling up from 30 gm to 500 and 1000 gm was highly successful confirming suitability of MTR as a preformulation tool
Image Segmentation Using Split and Merge Techniques with a Mixture of Heterogeneous Distributions
No full textImage segmentation is a technique that partitioned the image into prerequisite semantic unique regions. Simplifying the representation of an image into something more easily to analyze and meaningful is the ultimate goal of segmentation. It is used for locating boundaries and objects in an image such as lines, curves or object. Segmentation serves many computer applications such as pattern recognition, object recognition, automatic traffic
control, and many other applications. Image segmentation is considered the bottleneck in many image processing techniques.
There are a vast number of segmentation techniques that is available but none of them satisfy the global properties, so it is remain challenge for researcher to find best one. Thresholding is one of the simplest and effective techniques for image segmentation. It defines a threshold value T, and the gray values less than T will be considered as a class, and those above T belong to another class. The estimation of the optimal threshold T is still the big problem for image thresholding.
The aim of this thesis is to introduce a new method for image thresholding based on histogram split-merge technique with a mixture of heterogeneous distributions. The proposed method will be applied on different type of synthetic and real images; the results obtained will be compared to those of the existing methods
Biochemically altered human erythrocytes as a carrier for targeted delivery of primaquine: an In Vitro study.
No full textThe aim of this study was to investigate human erythrocytes as a carrier for targeted drug delivery of primaquine (PQ). The process of PQ loading in human erythrocytes, as well as the effect of PQ loading on the oxidative status of erythrocytes, was also studied. At PQ concentrations of 2, 4, 6, and 8 mg/mL and an incubation time of 2 h, the ratios of the concentrations of PQ entrapped in erythrocytes to that in the incubation medium were 0.515, 0.688, 0.697 and 0.788, respectively. The maximal decline of erythrocyte reduced glutathione content was observed at 8 mg/mL of PQ compared with native erythrocytes p < 0.001. In contrast, malondialdehyde and protein carbonyl were significantly increased in cells loaded with PQ (p < 0.001). Furthermore, osmotic fragility of PQ carrier erythrocytes was increased in comparison with unloaded cells. Electron microscopy revealed spherocyte formation with PQ carrier erythrocytes. PQ-loaded cells showed sustained drug release over a 48 h period. Erythrocytes were loaded with PQ successfully, but there were some biochemical as well as physiological changes that resulted from the effect of PQ on the oxidative status of drug-loaded erythrocytes. These changes may result in favorable targeting of PQ-loaded cells to reticulo-endothelial organs. The relative impact of these changes remains to be explored in ongoing animal studies