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101.
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103.
El‐Sayed M. El‐Sayed Ahmed M. Mansour Waleed S. El‐Sawy 《Journal of biochemical and molecular toxicology》2017,31(11)
Doxorubicin (DOX) exerts toxic effects in several organs particularly kidney. The present study aimed to assess the protective effect of proanthocyanidins (PAs) against DOX‐induced nephrotoxicity in rats. A single dose of DOX (7.5 mg/kg, i.v.) significantly increased kidney weight, kidney/body weight ratio, serum urea, creatinine, tumor necrosis factor alpha levels, and kidney contents of malondialdehyde, nitric oxide, cyclooxygenase‐2, and caspase‐3 activity with significant reduction in final body weight, serum albumin, kidney contents of reduced glutathione (GSH), and superoxide dismutase activity as compared with control group. In contrast, pretreatment with PAs (200 mg/kg, p.o.) for 14 days before DOX and for 7 days after DOX ameliorated kidney function and oxidative stress parameters. Histopathological evidence confirmed the protective effects of PAs from the tissue damage induced by DOX. In conclusion, PAs have a multi‐nephroprotective effect that might be attributed to its antioxidant, anti‐inflammatory, and antiapoptoic activities. 相似文献
104.
Mesenchymal stem cell therapy: A promising cell‐based therapy for treatment of myocardial infarction 下载免费PDF全文
Ayman El‐Sayed Shafei Mahmoud Ahmed Ali Hazem G. Ghanem Ahmed I. Shehata Ahmed A. Abdelgawad Hossam R. Handal Kareem A. Talaat Ahmed E. Ashaal Amal S. El‐Shal 《The journal of gene medicine》2017,19(12)
For decades, mesenchymal stem (MSCs) cells have been used for cardiovascular diseases as regenerative therapy. This review is an attempt to summarize the types of MSCs involved in myocardial infarction (MI) therapy, as well as its possible mechanisms effects, especially the paracrine one in MI focusing on the studies (human and animal) conducted within the last 10 years. Recently, reports showed that MSC therapy could have infarct‐limiting effects after MI in both experimental and clinical trials. In this context, various types of MSCs can help cardiac regeneration by either revitalizing the cardiac stem cells or revascularizing the arteries and veins of the heart. Furthermore, MSCs could produce paracrine growth factors that increase the survival of nearby cardiomyocytes, as well as increase angiogenesis through recruitment of stem cell from bone marrow or inducing vessel growth from existing capillaries. Recent research suggests that the paracrine effects of MSCs could be mediated by extracellular vesicles including exosomes. Exosomal microRNAs (miRNAs) released by MSCs are promising therapeutic hotspot target for MI. This could be attributed to the role of miRNA in cardiac biology, including cardiac regeneration, stem cell differentiation, apoptosis, neovascularization, cardiac contractility and cardiac remodeling. Furthermore, gene‐modified MSCs could be a recent promising therapy for MI to enhance the paracrine effects of MSCs, including better homing and effective cell targeted tissue regeneration. Although MSC therapy has achieved considerable attention and progress, there are critical challenges that remains to be overcome to achieve the most effective successful cell‐based therapy in MI. 相似文献
105.
Sayed WF 《Folia microbiologica》2011,56(1):1-9
Casuarinas are very important plants for their various uses and survival in adverse sites or harsh environments. As nitrogen
fixation, in symbiosis with Frankia, is an important factor for the survival of these plants under various conditions, the basis for selecting both effective
and tolerant Frankia strains and Casuarina spp., are provided. Enhancement of the symbiotic relationship between Frankia and Casuarina, by mycorrhizal infection and other biofertilizing microorganisms such as Bacillus and Azospirillum, is reflected by superior plant growth. Casuarina leaf litter is also a great source for both inorganic and organic nutrients. Therefore, careful management of the top soil
layer under Casuarina trees is very important. Litter decomposition ratio is affected by many physical chemical and biological factors including
temperature, moisture conditions, lignin, and C-to-N and N-to-P ratios in addition to soil biota. In general, here the above
relations are discussed and an alleviation model is presented for important disturbances of natural and human origin made
in soil and environment, especially in the dry regions. In conclusion, we suggest how to optimize the nitrogen fixation and
plant growth under the prevalent conditions. 相似文献
106.
Variety of butyl [2-arylamino-4,4-dimethyl-6-oxo-cyclohex-1-ene]carbodithioates (3a–c), 2-thioxo-6,7-dihydro-1H-benzo[d][1,3]thiazin-5(2H)-one derivatives (5a–c), and the glucosyl carbodithioates 6a–c as well as galactosyl carbodithioates 7a–c have been synthesized from the reaction of enaminone derivatives 1a–c with carbon disulfide followed by the alkylation with n-butyl bromide and α-d-glycosyl bromides, respectively. The amount of carbon disulfide plays a great role in the mode of reaction. The structures of the synthesized compounds were elucidated by spectral data and X-ray crystallography. 相似文献
107.
T. El‐Sayed Ali A. M. Osman S. H. Abdel‐Aziz F. A. Bawazeer 《Zeitschrift fur angewandte Ichthyologie》2011,27(3):840-846
Growth and longevity were studied for three species of the family scaridae, the longnose parrotfish (Hipposcarus harid), rusty parrotfish (Scarus ferrugineus) and bullethead parrotfish (Chlorurus sordidus), sampled at the eastern coast of the Red Sea, off Saudi Arabia. The three species are protogynous hermaphrodites presenting two distinct phases whereby the initial phase includes females and primary males, and the terminal phase is exclusively secondary males transformed from females. Annual marks in the ctenoid scales from the three species were used to develop size‐at‐age plots. Linear relationships were found between the scale radius and standard length for the three species, and the relationships between body weight (w) and standard length (L) were estimated. Scales of these species increased in size consistently throughout life, even though the somatic growth rate decreased with age. Sex‐specific growth effects in the three species were demonstrated. Growth of initial phase females was the lowest, followed by the initial phase males and terminal phase males, the latter showing the fastest growth rates. Thus, transition to the terminal male identity was associated with enhanced growth, resulting in larger terminal males than females of equivalent size. The von Bertalanffy growth formula (VBGF) was estimated for H. harid, S. ferrugineus and C. sordidus (L∞ = 43.92, 27.4 and 23.3; K = 0.067, 0.27 and 0.56; t0 = ?6.92, ?4.98 and ?4.6, respectively). The relationship between growth and reproduction of these species is also discussed. 相似文献
108.
Faten Zahran Mohamed Yousry Mostafa Hussein Ibrahim Mohey El-Deen Marwa Sayed Sabea 《Molecular biology reports》2014,41(3):1461-1468
Hepatocellular carcinoma (HCC) is a worldwide neoplasm for which early diagnosis is difficult and the prognosis is usually poor. Overexpression of cyclooxygenase 2 (COX-2) has been suggested to be associated with hepatocarcinogenesis. Although several COX-2 inhibitors have been used in hepatoma therapy, the genetic background between COX-2 and HCC remains largely unknown. In this study, the association of genotypic polymorphisms in COX-2 with HCC was investigated. 25 healthy individuals served as control (group I), group II: 50 HCV infection patients without any complications, group III: 50 HCV infected patients complicated with cirrhosis and group IV: 75 HCV infected patients complicated with (45 localized and 30 metastatic) HCC from Zagazig University Hospital in Egypt were genotyped by a PCR–RFLP method. The results showed that, no differences in distribution between the HCC and other groups were found. We found ?1195A allele carriers had a higher risk of HCC with HCV infection. As regard the obtained results of serum AFU, a significant increase was detected in HCC as compared with cirrhosis, hepatitis and healthy control groups (p < 0.001). Concerning the obtained results of serum AFP, when HCC group was compared with cirrhosis, hepatitis and healthy controls, a significant increase was observed (p < 0.001). In conclusion: identification of SNP in COX-2 gene promoter and evaluation of serum AFU and AFP give a red light in early detection of HCC which may be reduce its fatal incidence. 相似文献
109.
Mohammad Mobarak Hossain Sayed Koushik Ahamed Syed Masudur Rahman Dewan Md Mahadi Hassan Arif Istiaq Mohammad Safiqul Islam Md Mizanur Rahman Moghal 《Biological research》2014,47(1)
Background
The study was conducted to evaluate the in vitro antimicrobial activity, cytotoxic, and membrane stabilization activities, and in vivo antiemetic and antipyretic potentials of ethanolic extract, n-hexane and ethyl acetate soluble fractions of Spilanthes paniculata leaves for the first time widely used in the traditional treatments in Bangladesh.Results
In antipyretic activity assay, a significant reduction (P < 0.05) was observed in the temperature in the mice tested. At dose 400 mg/kg-body weight, the n-hexane soluble fraction showed the effect (36.7 ± 0.63°C ) as like as the standard (dose 150 mg/kg-body weight) after 5 h of administration. Extracts showed significant (P < 0.001) potential when tested for the antiemetic activity compared to the standard, metoclopramide. At dose 50 mg/kg-body weight, the standard showed 67.23% inhibition, whereas n-hexane and ethyl acetate soluble fractions showed 37.53% and 24.93% inhibition of emesis respectively at dose 400 mg/kg-body weight. In antimicrobial activity assay, the n-hexane soluble fraction (400 μg/disc) showed salient activity against the tested organisms. It exerts highest activity against Salmonella typhi (16.9 mm zone of inhibition); besides, crude, and ethyl acetate extracts showed resistance to Bacillus cereus and Bacillus subtilis, and Vibrio cholera respectively. All the extracts were tested for lysis of the erythrocytes. At the concentration of 1mg/ml, ethanol extract, and n-hexane and ethyl acetate soluble fractions significantly inhibited hypotonic solution induced lysis of the human red blood cell (HRBC) (27.406 ± 3.57, 46.034 ± 3.251, and 30.72 ± 5.679% respectively); where standard drug acetylsalicylic acid (concentration 0.1 mg/ml) showed 77.276 ± 0.321% inhibition. In case of heat induced HRBC hemolysis, the plant extracts also showed significant activity (34.21 ± 4.72, 21.81 ± 3.08, and 27.62 ± 8.79% inhibition respectively). In the brine shrimp lethality bioassay, the n-hexane fraction showed potent (LC50 value 48.978 μg/ml) activity, whereas ethyl acetate fraction showed mild (LC50 value 216.77 μg/ml) cytotoxic activity.Conclusions
Our results showed that the n-hexane extract has better effects than the other in all trials. In the context, it can be said that the leaves of S. paniculata possess remarkable pharmacological effects, and justify its folkloric use as antimicrobial, antipyretic, anti-inflammatory, and antiemetic agent. Therefore, further research may be suggested to find possible mode of action of the plant part. 相似文献110.
Golam Sarwar Raju Md Mizanur Rahman Moghal Mohammad Salim Hossain Md Mahadi Hassan Md Mustahsan Billah Sayed Koushik Ahamed SM Masud Rana 《Biological research》2014,47(1)