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71.
Hesham M. Sharaf 《Saudi Journal of Biological Sciences》2009,16(1):51-55
The present study was designed to investigate histochemically the detection of carbohydrate and protein in the normally feeding snails and after 15 and 30 days of starvation. Generally, abundant carbohydrate and protein materials were detected in the component cells of the digestive gland of normally feeding snails. The results of this investigation revealed a pronounced decline of carbohydrates in the digestive gland cells of Monacha cartusiana snails after starvation. Severe decline in carbohydrate content was observed especially after 30 days of starvation. Moreover, protein inclusions have exhibited a week stainability in the digestive gland cells of these snails as a consequence of starvation. 相似文献
72.
Esam Aboutaleb Manish Kothari Osama Damrah Roben Canelo 《International Seminars in Surgical Oncology : ISSO》2009,6(1):17
Background
Gastrointestinal stromal tumours are rare (GIST). However, the incidence of GIST among neurofibromatosis type 1 (NF-1) patients is approximately 3.9-25%. GIST can present clinically in different ways such as abdominal pain, gastrointestinal bleeding and obstruction.Case report
We present 51 year female patient admitted with Background of neurofibromatosis type 1 admitted with melena. OGD has been done and showed duodenitis with large volume fresh blood in distal duodenum but no obvious bleeding point. Exploratory laparotomy revealed smooth nodular masses on the serosal surface of jejunum. Small bowel resection and side-to-side anastomosis were performed. Histopathoogical examination revealed small bowel gasrointestinal stromal tumour with low risk malignant potential.Conclusion
The incidence of GIST among neurofibromatosis type 1 (NF-1) patients is not uncommon and we should pay attention to gastrointestinal manifestation in such patients.73.
The purpose of the present study was to prepare intranasal delivery system of sildenafil citrate and estimate its relative
bioavailability after nasal administration in rabbits to attain rapid onset of action with good efficacy at lower doses. Sildenafil
citrate saturated solubility was determined in different solvents, cosolvents, and microemulsion systems. For nasal application,
sildenafil citrate was formulated in two different systems: the first was a cosolvent system (S3) of benzyl alcohol/ethanol/water/Transcutol/taurodeoxy
cholate/Tween 20 (0.5:16.8:47.7:15.9:1:18.1% w/w). The second was a microemulsion system (ME6) containing Oleic acid: Labrasol/Transcutol/water (8.33:33.3:16.66:41.66% w/w). The prepared systems were characterized in relation to their clarity, particle size, viscosity, pH, and nasal ciliotoxicity.
In vivo pharmacokinetic performance of the selected system ME6 (with no nasal ciliotoxicity) was evaluated in a group of six rabbits
in a randomized crossover study and compared to the marketed oral tablets. The targeted solubility (>20 mg/ml) of sildenafil
citrate was achieved with cosolvent systems S1, S3, and S5 and with microemulsion systems ME3–ME6. The saturated solubility
of sildenafil citrate in cosolvent system S3 and microemulsion system ME6 were 22.98 ± 1.26 and 23.79 ± 1.16 mg/ml, respectively.
Microemulsion formulation ME6 showed shorter t
max (0.75 h) and higher AUC(0-∞) (1,412.42 ng h/ml) compared to the oral tablets which showed t
max equals 1.25 h and AUC(0-∞) of 1,251.14 ng h/ml after administration to rabbits at dose level of 5 mg/kg. The relative bioavailability was 112.89%. In
conclusion, the nasal absorption of sildenafil citrate microemulsion was found to be fast, indicating the potential of nasal
delivery instead of the conventional oral administration of such drug. 相似文献
74.
Riham I. Ahmed Essam Eldin A. Osman Samir M. El-Moghazy 《Journal of enzyme inhibition and medicinal chemistry》2017,32(1):176-188
New target compounds were designed as inhibitors of tubulin polymerization relying on using two types of ring B models (cyclohexenone and indazole) to replace the central ring in colchicine. Different functional groups (R1) were attached to manipulate their physicochemical properties and/or their biological activity. The designed compounds were assessed for their antitumor activity on HCT-116 and MCF-7 cancer cell lines. Compounds 4b, 5e and 5f exhibited comparable or higher potency than colchicine against colon HCT-116 and MCF-7 tumor cells. The mechanism of the antitumor activity was investigated through evaluating the tubulin inhibition potential of the active compounds. Compounds 4b, 5e and 5f showed percentage inhibition of tubulin in both cell line homogenates ranging from 79.72% to 89.31%. Cell cycle analysis of compounds 4b, 5e and 5f revealed cell cycle arrest at G2/M phase. Molecular docking revealed the binding mode of these new compounds into the colchicine binding site of tubulin. 相似文献
75.
Osama Mahmoud Andrew Harrison Aris Perperoglou Asma Gul Zardad Khan Metodi V Metodiev Berthold Lausen 《BMC bioinformatics》2014,15(1)
Background
Microarray technology, as well as other functional genomics experiments, allow simultaneous measurements of thousands of genes within each sample. Both the prediction accuracy and interpretability of a classifier could be enhanced by performing the classification based only on selected discriminative genes. We propose a statistical method for selecting genes based on overlapping analysis of expression data across classes. This method results in a novel measure, called proportional overlapping score (POS), of a feature’s relevance to a classification task.Results
We apply POS, along‐with four widely used gene selection methods, to several benchmark gene expression datasets. The experimental results of classification error rates computed using the Random Forest, k Nearest Neighbor and Support Vector Machine classifiers show that POS achieves a better performance.Conclusions
A novel gene selection method, POS, is proposed. POS analyzes the expressions overlap across classes taking into account the proportions of overlapping samples. It robustly defines a mask for each gene that allows it to minimize the effect of expression outliers. The constructed masks along‐with a novel gene score are exploited to produce the selected subset of genes.Electronic supplementary material
The online version of this article (doi:10.1186/1471-2105-15-274) contains supplementary material, which is available to authorized users. 相似文献76.
Iman O. Sherif Azza Abdel‐Aziz Osama M. Sarhan 《Journal of biochemical and molecular toxicology》2014,28(11):515-521
In the present study, the effect of arjunolic acid on testicular damage induced by intraperitoneal injection of rats with 7 mg/kg cisplatin was studied. Cisplatin induced a significant reduction in testicular weights, plasma testosterone, and testicular reduced glutathione levels in addition to a significant elevation of testicular malondialdehyde levels and testicular gene expressions of inducible nitric oxide synthase (iNOS), tumor necrosis factor‐α (TNF‐α), and p38 mitogen‐activated protein kinase (MAPK) when compared with the control group (p < 0.05). Lower tubular diameters and depletion of germ cells and irregular small seminiferous tubules with Sertoli cells only were observed in the cisplatin group. Arjunolic acid administration significantly corrected the changes in both biochemical and histopathological parameters. Arjunolic acid plays a significant protective role against cisplatin‐induced testicular injury by attenuating oxidative stress parameters along with downregulation of iNOS, TNF‐α, and p38‐MAPK testicular expressions. 相似文献
77.
Osama M. Abo‐Salem Gamaleldin I. Harisa Tarek M. Ali El‐Sayed M. El‐Sayed Fatma M. Abou‐Elnour 《Journal of biochemical and molecular toxicology》2014,28(6):263-270
Heart failure (HF) is one of diabetic complications. This work was designed to investigate the possible modulatory effect of curcumin against streptozotocin‐induced diabetes and consequently HF in rats. Rats were divided into control, vehicle‐treated, curcumin‐treated, diabetic‐untreated, diabetic curcumin–treated, and diabetic glibenclamide–treated groups. Animal treatment was started 5 days after induction of diabetes and extended for 6 weeks. Diabetic rats showed significant increase in serum glucose, triglycerides, total cholesterol, low‐density lipoprotein‐cholesterol, very low density lipoprotein‐cholesterol, nitric oxide, lactate dehydrogenase, cardiac malondialdehyde, plasma levels of interleukin‐6, and tumor necrosis factor‐alpha, and also showed marked decrease in serum high‐density lipoprotein‐cholesterol, cardiac reduced glutathione, and cardiac antioxidant enzymes (catalase, superoxide dismutase, and glutathione‐S‐transferase). However, curcumin or glibenclamide treatment significantly mitigated such changes. In conclusion, curcumin has a beneficial therapeutic effect in diabetes‐induced HF, an effect that might be attributable to its antioxidant and suppressive activity on cytokines. 相似文献
78.
Manal M. Elbandrawy Osama Sweef Doaa Elgamal Tarek M. Mohamed EhabTousson Rehab M. Elgharabawy 《Saudi Journal of Biological Sciences》2022,29(5):3871
BackgroundType 2 diabetes (T2DM) is a chronic metabolic disorder. Although therapeutic pharmaceutical agents continue to advance, herbal medicines are potential complementary treatments for the promotion of glucose homeostasis, with minimal adverse effects. Conventionally, ellagic acid (EA) has been utilized for the therapy of a range of pathologies owing to its anti-inflammatory and anti-diabetic actions.ObjectiveThe aim of this study is to determine the activity of EA on serum α-amylase and lipase titers, and on pancreatic tumor necrosis factor-α (TNF-α), proliferating cell nuclear antigen (PCNA) and interleukin-6 (IL-6) concentrations using the streptozocin-induced T2DM rodent model.MethodsEA extract synthesized from fresh strawberry fruit was employed for therapy. 50 adults male Wistar rats were randomized into either control, EA, diabetic, co-treated or post- treated cohorts.ResultsEA diminished fasting blood glucose levels, altered lipase, amylase, IL-6, PCNA and TNF- α expression and enhanced islet cell renewal, insulin, and immunoreactivities.ConclusionInflammatory indicators are elevated in the presence of T2DM. Extract of EA has overall tissue reparative and safeguarding properties, as indicated by the augmented β- cell population and enhanced glucose homeostasis. Thus, EA may be an innovative treatment approach for the maintenance of normoglycemia in individuals with T2DM. 相似文献
79.
80.
MIF‐173G/C (rs755622) polymorphism as a risk factor for acute lymphoblastic leukemia development in children 下载免费PDF全文