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Lithium Induced Toxicity in Rats: Blood Serum Chemistry, Antioxidative Enzymes in Red Blood Cells and Histopathological Studies
No full textLithium is commonly used in treating mental disorders and bipolar diseases. As physicians frequently keep the patients on long-term lithium therapy, awareness of the numerous side effects and pathogenesis of this lightest alkali metal is needed for such treatments. The present study was designed to evaluate the toxic effect of small doses of lithium chloride in male Wistar rats. The oral administration of lithium chloride (15 and 30 mg/kg body wt) for 7 weeks through their drinking water elicited a significant alteration in their body weight and blood serum chemistry. The serum enzyme activities of alkaline phosphatase (ALP), high density lipoprotein (HDLP), and creatinine kinase (CK) were diminished, whereas the level of serum urea and glucose were elevated in the lithium treated animals, depicting the disturbed general physiological status. Furthermore, a marked inhibition in the activities of serum alanine and aspartate transaminases (ALT and AST) reflected a stimulating transamination reaction in hepatic and renal tissues. Lithium exposure also reduced the glutathione (GSH) level and stimulated the lipid peroxidation (LPO) level in the rat blood cells, indicating oxidative stress in the red blood cells due to lithium exposures. The histopathological observations of the liver and kidney tissues revealed many deformities and histological alterations due to lithium treatment. The results of present study suggest that small doses of lithium induce toxicity in rat blood as well as in liver and kidney tissues. However, the precise mechanism of lithium toxicity is still incompletely understood
Effectiveness of an infant oral health care educational intervention on knowledge of dental student
No full textPurpose: This study evaluated the effectiveness of an infant oral health care educational intervention on the knowledge of dental students in female dental college at King Saud University (KSU) in Riyadh city. Methods: One hundred and twenty eight students participated in the study. The participants were from different levels in the dental college: second year (D2), third year (D3), fourth year (D4) and fifth year (D5). Assessment in the form of a questionnaire was completed immediately before and after a 14-minute educational intervention, which was in the form of a PowerPoint presentation and video of infant oral health for dental students. The 18 multiple choice questions questionnaire was based on the information presented in the presentation. Results: A significant difference (P<0.001) was found between the average pretest scores (9.30±2.24), and the average post-test scores (12.56±2.05). The highest percentage of improvement in the post-test as compared to pretest was recorded for group D2 (50.6%) followed by D3 (40%), D4 (35%), and D5 (23%).One hundred twenty six (98.4%) study participants found the presentation helpful in improving their understanding of infant oral health, and 77 (60.2%) were very satisfied with the presentation. Sixty-six (51.6%) reported that the presentation was very effective in teaching them about infant oral health, 83(65%) were very likely to incorporate this information into their daily practice. Conclusions: A 14-minutes PowerPoint and video educational intervention was effective in teaching dental student basic information on infant oral health.King Saud Universit
Tooth wear, enamel hypoplasia and traumatic dental injuries among cerebral palsy children of Riyadh city
No full textObjectives: To determine and describe tooth wear, enamel hypoplasia and traumatic dental injuries (TDI) in cerebral palsy (CP) children of Riyadh city. Methods: One hundred and forty non-institutionalized CP children (82 males & 58 females) were examined in the dental clinic of the Disabled Children Association Center, Riyadh, for presence of tooth wear, enamel hypoplasia and traumatic dental injuries. Results: The children were divided into three age groups; the first group (3-6 years) consisted of 41 children, second group (7-9 years) consisted of 52 children and third group (10-12 years) had 47 children. The prevalence of tooth wear was 9.3%, while enamel hypoplasia was found in 25% of the children. Age and gender were not correlated to tooth wear or enamel hypoplasia in the examined CP children (p>0.05). TDI were recorded in 12.1% of the children with a statistically significant difference between the first age group and; the second and third age groups (p<0.05). The incidence of TDI was higher in older age groups with no statistically significant difference between males and females (p>0.05). Conclusions: About one in each ten children examined had tooth wear, while one quarter of them had enamel hypoplasia. Age and gender were not correlated to tooth wear or enamel hypoplasia. More than one tenth of the examined CP children had TDI with higher incidence in older age group.CDRC, College of Dentistry Research Center, King Saud Universit
Bond strengths of custom cast and prefabricated posts luted with two cements.
No full textOBJECTIVE: This in vitro study evaluated the bond strength of custom cast and prefabricated posts luted with resin or zinc phosphate cements into unobturated canals of extracted teeth. Method and Materials: Forty-eight custom cast and prefabricated posts were placed into extracted single-rooted human teeth. Post-cavity preparation was 1.5 mm in diameter and 10 mm in depth. Specimens were randomly divided into 4 groups of 12 each. Two of the groups were then luted with resin cement, while the other two groups were luted with zinc phosphate cement. A pull-out bond strength evaluation was performed using a universal testing machine. The Kolmogorov-Smirnov test was used to prove normal distribution. Data were statistically analyzed using two-way ANOVA and the Student t test (alpha = .05). RESULTS: For both luting agents, the prefabricated posts group exhibited significantly less bond strength than the custom cast posts group (P = .0001). There were statistically significant differences in mean bond strength for the prefabricated posts group luted with resin cement vs the group cemented with zinc phosphate cement (P = .002). There was no significant difference between the mean bond strength values of custom cast posts luted with resin cement or zinc phosphate cement. CONCLUSION: Custom cast posts showed significantly greater bond strength than prefabricated posts when luted with either resin or zinc phosphate cements. The type of cement had less significance on the retention of custom cast posts.King Saud Universit
Oxidative CO2 Reforming of CH4 over Ni/ -Al2O3 Catalyst
No full textOxidative carbon dioxide reforming of methane to synthesis gas over alumina-supported Ni catalysts was investigated at atmospheric pressure. The reforming reactions were carried out using a CO2 to CH4 feed ratio of one and reaction temperatures range of 600-800°C. The activity and stability of the catalyst, carbon deposition, and synthesis gas (H2/CO) ratio were determined. Catalyst deactivation was primarily due to coke formation. EDS, SEM and TGA techniques were used to confirm carbon deposition. It was observed that increasing the oxygen feed concentration and/or reaction temperatures, enhanced methane conversion and reduced coke formation. Catalyst stability test revealed that the highest CH4 conversion of 99.7% associated with the lowest drop in CH4 conversion of 1% and lowest carbon formation of 1% were obtained when 20% O2 was introduced with the feed at 800°C
Structure and Physical Properties of Polymer Composite Films Doped with Fullerene Nanoparticles
No full textFullerene C60 has stimulated intense interest for scientific, industrial, and medical community because of its unique structure and properties. In the present study we prepared fullerene-doped nanocomposite films based on PMMA, PVAc, and PMMA/PVAc blend. Observations made by transmission electron microscope (TEM) showed the uniform dispersion of C60 nanoparticles in the polymer matrices. Also, X-ray diffraction measurements indicated that C60 has a tendency to form crystallites in the polymer matrices. In addition, the concentration effect of fullerene C60 was investigated using optical absorption and photoluminescence spectroscopy. The spectroscopic properties of such films recommended their application in photonics and solar energy conversion.King Saud Universit
A described of some factors that affect the self-concept of university students
No full textBy self concept it is meant the way one conceives him self. It includes the perception of one’s characteristics and abilities, one’s interaction with other people and the environment, one’s values associated with experiences and objects and one’s goals and ideals. If one accepts that self –concept is best regarded as a dynamic complex of attitudes , then a positive self-concept can be equated with a positive self evaluation , self- respect , self-esteem , self acceptance , while negative self concept becomes synonymous with a negative self- evaluation , self hatred , inferiority and a lack of feeling of personal worthiness and self acceptance .
The study aims to investigate the self-concept among a group of university Students in Saudi Arabia, to describe the Factors that affect the self- concept among group of university Students in Saudi Arabia such as teacher, scholastic achievement, satisfaction, age, the year a student is in college etc.......
Research design, a cross-sectional investigation design was applied to suit with the nature of the present study.
Research Setting, this study was conducted at College of Health Sciences, Yanbu Campus, Taibah University, Saudi Arabia. Subjects, the sample of this study will include all students in first and final level of education at above mentioned settings, [n=290 students].
Tools used for data collection an interview questionnaire to gather demographic data. The Tennessee self-concept; developed by fitts will be adopted to measure self concept of nursing students.Results Shows There was a significant relationship between Students’ Academic Achievement and Self Concept (p = 0.000) &There was a significant relationship between Satisfaction by the Students and Self Concep
EFFECTIVNESS OF CREATINE AND CYCLOSPORINE TO PROTECT AGAINST PROPIONIC ACID- INDUCED NEUROTOXICITY.
No full textObjectives: This work aims to study the neuroprotective effect of creatine and cyclosporine in ameliorating the neurotoxic effects of orally administrated propionic acid to young rats.
Methods: Young male rats (n= 32) were divided into four groups; oral buffered propionic acid - treated group, cyclosporine and creatine protected groups followed by propionic acid. A fourth control group. Reduced glutathione, malondialdehyde, vitamin C, catalase and Comet DNA were assayed in brain homogenates.
Results: It was observed that propionic acid caused brain degeneration as measured by reduced glutathione and vitamin C depletion together with the increase of malondialdehyde as a marker of oxidative stress. Decreased lactate oxidase activity in brain homogenates of propionic acid-treated rats was attributed to the leakage of the enzyme from brain, while increase of creatine kinase activity suggested a compensatory mechanism to overcome ATP depletion. In addition, propionic acid induced DNA strand breaks. Creatine administration prior to propionic acid treatment was greatly protective showing elevated reduced glutathione and vitamin C levels, decreased lipid peroxidation and lactate oxidase release from brain to plasma, and DNA damage. On the other hand, cyclosporine treatment was less protective compared to creatine.
Conclusion: These findings prove that propionic induced brain degeneration in young rats and confirm the protective efficacy of creatine as a nutritional supplement could be used to treat early diagnosed patients with autism, a disease related to propionic acid neurotoxicity.Sabi
A Route to Dicyanomethylene Pyridines and Substituted Benzonitriles Utilizing Malononitrile Dimer as a Precursor
No full textAbstract: The conditions of the reaction of malononitrile dimer with enaminones and arylidenemalononitrile could be adapted to yield either pyridines or benzene derivatives. A new synthesis of pyrido[1,2-a]pyrimidines from the reaction of malononitrile dimer 1 and 2-phenyl-3-piperidin-1-yl-acrylonitrile (11) is described. Compound 1 condensed with DMFDMA to yield an enaminonitrile that reacted with hydrazine hydrate to yield N',4,6-triamino-2H-pyrazolo[3,4-b]pyridine-5-carboxamidine (1
Anti-proliferative Effects of Organic Extracts from Root Bark of Juglans Regia L. (RBJR) on MDA-MB-231 Human Breast Cancer Cells: Role of Bcl-2/Bax, Caspases and Tp53
No full textWith increasing use of plant-based cancer chemotherapeutic agents, exploring the antiproliferative effects of phytochemicals has gained increasing momentum for anticancer drug design. The present study was undertaken to investigate the effect of root bark of Juglans regia (RBJR) organic extracts on cell proliferation, and to determine the molecular mechanism of RBJR-induced cell death by determining the expression of Bcl-2, Bax, caspases, Tp53, Mdm-2 and TNF-α in MDA-MB-231 human breast cancer cells. The results demonstrate that WNRB suppressed proliferation and induced apoptosis in a dose and time dependent manner by modulating expression of key genes. This involved characteristic changes in cytoplasmic and nuclear morphology, DNA fragmentation (TUNEL assay), levels of mRNA and expression of corresponding proteins. Real Time PCR and western blot analysis revealed that the expression of of Bax, caspases, tp53, and TNF-α was markedly increased in MBA-MB-231 cells treated with the RBJR extract. In contrast Bcl2 and mdm-2 expression was down regulated after exposure. In summary, our data suggest the presence of bioactive compound(s) in WNRB capable of killing breast carcinoma cells through induction of apoptosis, and therefore a candidate source of anticancer drugs