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1.
Md. Ejaz Ahmed Mohd. Moshahid Khan Hayate Javed Kumar Vaibhav Andleeb Khan Rizwana Tabassum Mohammad Ashafaq Farah Islam Mohammed M. Safhi Fakhrul Islam 《Neurochemistry international》2013
Alzheimer’s disease (AD) is a progressive neurodegenerative disorder resulting in cognitive decline and enhancement of oxidative loads in the brain. Flavonoids have been considered to exert human health benefits by anti-oxidant and anti-inflammatory properties. The present study is aimed to elucidate the neuroprotective effect of catechin hydrate (CH), a natural flavanoid with potential antioxidant and anti-inflammatory properties, on intracerebroventricular streptozotocin (ICV-STZ) induced neuronal loss and memory impairment. To test this hypothesis, male Wistar rats were pretreated with CH (10 and 20 mg/kg bwt) orally once daily for 21 days and then bilaterally injected with ICV-STZ (3 mg/kg bwt), while sham group rats receive the same volume of vehicle. After 2 weeks of ICV-STZ infusion, rats were tested for cognitive performance using Morris water maze (MWM) test and then sacrifice for biochemical and histopathological assays. CH was found to be successful in upregulating the antioxidant status and prevented the memory loss. The expression of choline acetyl transferase (ChAT) was decreased in ICV-STZ group and CH pretreatment increases the expression of ChAT. Moreover, inflammatory mediators like TNF-α, IL-1β levels and expression of iNOS were significantly attenuated by CH pretreatment. The study suggests that CH is effective in preventing memory loss, ameliorating the oxidative stress and might be beneficial for the treatment of sporadic dementia of Alzheimer’s type (SDAT). 相似文献
2.
Hamed Zakikhani Mohd. Khanif Yusop Mohamed Musa Hanafi Radziah Othman Amin Soltangheisi 《Chemical Speciation and Bioavailability》2016,28(1-4):170-181
Intermittently submergence and drainage status of paddy fields can cause alterations in morphological and chemical characteristics of soils. We conducted a sequential fractionation study to provide an insight into solubility of Sulfur (S) and Molybdenum (Mo) in flooded alluvial paddy soils. The samples (0–15 and 15–30 cm) were taken from marine and riverine alluvial soils in Kedah and Kelantan areas, respectively, and were sequentially extracted with NaHCO3, NaOH, HCl, and HClO4–HNO3. Total S in upper and lower layers of Kedah and Kelantan ranged between 273 and 1121 mg kg?1, and 177 to 1509 mg kg?1, respectively. In upper layers and subsoil of Kedah, average total Mo were 0.34 and 0.27 mg kg?1, respectively. Average total Mo in Kelantan were 0.25 mg kg?1 (surface layer) and 0.28 mg kg?1 (subsoil). Cation exchange capacity (CEC) was positively correlated with plant available amounts of Mo in upper layers of Kedah area. Also, total and medium-term plant-available S was correlated with total carbon (C) at lower layers of Kelantan soil series. But in surface layers of Kelantan soil series, CEC was strongly correlated with total and medium-term plant-available S. Our results indicates that the influence of flooding conditions on soil S and Mo contents in paddy fields may cause long-term changes in S and Mo chemical reactivities. 相似文献
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Immunohistochemical expression of pi class glutathione S-transferase and alpha-fetoprotein in hepatocellular carcinoma and chronic liver disease 总被引:6,自引:0,他引:6
Yusof YA Yan KL Hussain SN 《Analytical and quantitative cytology and histology / the International Academy of Cytology [and] American Society of Cytology》2003,25(6):332-338
OBJECTIVE: To determine whether tumor marker pi glutathione transferase (GST-pi) is expressed in hepatocellular carcinoma (HCC) and other chronic liver diseases and to compare its expression with that of alpha-fetoprotein (AFP). STUDY DESIGN: Samples used were formalin-fixed, paraffin-embedded liver tissues: normal (n = 3), chronic hepatitis B (n = 15), cirrhosis (n = 15) and HCC (n = 30). The expression of AFP and GST-pi was detected by using immunohistochemistry with the peroxidase-antiperoxidase method. AFP immunoreactivity was based on the cytoplasm of the hepatocytes, while GST-pi immunoreactivity was based on the nuclei of hepatocytes. RESULTS: In normal liver tissues, AFP was not expressed. However, there was strong staining of GST-pi in bile duct epithelium cells and weak staining in hepatocytes. Our results showed higher AFP immunoreactivity in cases of HCC (36.7%) as compared to cirrhosis (6.7%) and hepatitis B (0%), whereas GST-pi immunoreactivity was lower in cases of HCC (53.3%) as compared to cases of cirrhosis (100.0%) and hepatitis B (93.3%). Percent sensitivity of AFP determination for HCC was 36.7% as compared to 53.3% for GST-pi, thus making GST-pi a more sensitive marker for detection of HCC. This study showed a significant relationship between the intensity and percentage of cells stained in hepatitis B, cirrhosis and HCC for GST-pi immunoreactivity (P < .001, .001 and .05, respectively) but not for AFP (P > .05). Statistical analysis showed that there was no significant relationship between expression of AFP and GST-pi in cirrhosis and HCC cases. Hepatitis B virus infection in HCC cases showed a positive rate of 46.7%, with AFP staining positively in 42.9% of tissues and GST-pi staining positively in 57.1% of tissues. CONCLUSION: AFP is a diagnostic but rather insensitive tissue marker for HCC. However, the absence of AFP in benign chronic liver disease makes this marker useful in differentiating between HCC and other chronic liver diseases, whereas GST-pi can be used as a diagnostic marker for HCC as well as in detecting other chronic liver diseases. 相似文献
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Expression of protective antigen in transgenic plants: a step towards edible vaccine against anthrax 总被引:5,自引:0,他引:5
Aziz MA Singh S Anand Kumar P Bhatnagar R 《Biochemical and biophysical research communications》2002,299(3):345-351
Protective antigen (PA) is the most potent molecule for vaccination against anthrax. In the present study, we have successfully integrated protective antigen gene in nuclear genome of tobacco plants by Agrobacterium mediated leaf-disc transformation method. Expression of protective antigen gene was detected by immunoblot analysis using antisera raised against purified PA. A distinct band of approximately 83kDa lighted up in the protein extracted from transformed plants while there was no such band in untransformed plants. The plant expressed PA showed biological activity just like native PA, which was demonstrated by cytolytic assay on macrophage like cell lines with lethal factor. This study establishes for the first time expression of PA gene in a plant system and thus marks the first milestone towards developing edible vaccine against anthrax. 相似文献
7.
DNA replication occurs almost exclusively during S-phase of the cell cycle and represents a simple biochemical metric of cell division. Previous methods for measuring cell proliferation rates have important limitations. Here, we describe experimental protocols for measuring cell proliferation and death rates based on the incorporation of deuterium ((2)H) from heavy water ((2)H(2)O) into the deoxyribose moiety of purine deoxyribonucleotides in DNA of dividing cells. Label incorporation is measured by gas chromatography/mass spectrometry. Modifications of the basic protocol permit analysis of small cell samples (down to 2,000 cells). The theoretical basis and operational requirements for effective use of these methods to measure proliferation and death rates of cells in vivo are described. These methods are safe for use in humans, have technical and interpretation advantages over alternative techniques and can be used on small numbers of cells. The protocols enable definitive in vivo studies of the fraction or absolute number of newly divided cells and their subsequent survival kinetics in animals and humans. 相似文献
8.
Protoplasma - Vesicular trafficking between endoplasmic reticulum and Golgi plays a major role in the growth and proliferation of breast cancer cells. Various proteins regulate this ER-Golgi... 相似文献
9.
Yusuf Oloruntoyin AYIPO Sani Najib YAHAYA Halimah Funmilayo BABAMALE Iqrar AHMAD Harun PATEL Mohd Nizam MORDI 《Turkish Journal of Biology》2021,45(4):503
The nsp3 macrodomain is implicated in the viral replication, pathogenesis and host immune responses through the removal of ADP-ribosylation sites during infections of coronaviruses including the SARS-CoV-2. It has ever been modulated by macromolecules including the ADP-ribose until Ni and co-workers recently reported its inhibition and plasticity enhancement unprecedentedly by remdesivir metabolite, GS-441524, creating an opportunity for investigating other biodiverse small molecules such as β-Carboline (βC) alkaloids. In this study, 1497 βC analogues from the HiT2LEAD chemical database were screened, using computational approaches of Glide XP docking, molecular dynamics simulation and pk-CSM ADMET predictions. Selectively, βC ligands, 129, 584, 1303 and 1323 demonstrated higher binding affinities to the receptor, indicated by XP docking scores of –10.72, –10.01, –9.63 and –9.48 kcal/mol respectively than remdesivir and GS-441524 with –4.68 and –9.41 kcal/mol respectively. Consistently, their binding free energies were –36.07, –23.77, –24.07 and –17.76 kcal/mol respectively, while remdesivir and GS-441524 showed –21.22 and –24.20 kcal/mol respectively. Interestingly, the selected βC ligands displayed better stability and flexibility for enhancing the plasticity of the receptor than GS-441524, especially 129 and 1303. Their predicted ADMET parameters favour druggability and low expressions for toxicity. Thus, they are recommended as promising adjuvant/standalone anti-SARS-CoV-2 candidates for further study.Key words: SARS-CoV-2, nsp3 macrodomain, ADP-ribose, β-carboline, bioinformatics, drug design 相似文献
10.
Brian Sheng Xian Teo Mahiran Basri Mohd Rezuwan Shah Zakaria Abu Bakar Salleh Raja Noor Zaliha Raja Abdul Rahman Mohd Basyaruddin Abdul Rahman 《Journal of nanobiotechnology》2010,8(1):4