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21.
Mashitoh Abd Rahman Faiqah Ramli Hamed Karimian Firouzeh Dehghan Noraziah Nordin Hapipah Mohd Ali Syam Mohan Najihah Mohd Hashim 《PloS one》2016,11(3)
Artonin E is a prenylated flavonoid isolated from the stem bark of Artocarpus elasticus Reinw.(Moraceae). This study aimed to investigate the apoptotic mechanisms induced by artonin E in a metastatic human ovarian cancer cell line SKOV-3 in vitro. MTT assay, clonogenic assay, acridine orange and propidium iodide double staining, cell cycle and annexin V analyses were performed to explore the mode of artonin E-induced cell death at different time points. DNA laddering, activation of caspases-3, -8, and -9, multi-parametric cytotoxicity-3analysis by high-content screening, measurement of reactive oxygen species generation, and Western blot were employed to study the pathways involved in the apoptosis. MTT results showed that artonin E inhibited the growth of SKOV-3 cells, with IC50 values of 6.5±0.5μg/mL after 72 h treatment, and showed less toxicity toward a normal human ovarian cell lineT1074, with IC50 value of 32.5±0.5μg/mL. Results showed that artonin E induced apoptosis and cell cycle arrest at the S phase. This compound also promoted the activation of caspases-3, -8, and -9. Further investigation into the depletion of mitochondrial membrane potential and release of cytochrome c revealed that artonin E treatment induced apoptosis via regulation of the expression of pro-survival and pro-apoptotic Bcl-2 family members. The expression levels of survivin and HSP70 proteins were also down regulated in SKOV-3 cells treated with artonin E. We propose that artonin E induced an antiproliferative effect that led to S phase cell cycle arrest and apoptosis through dysregulation of mitochondrial pathways, particularly the pro- and anti-apoptosis signaling pathways. 相似文献
22.
Kholoud S. Ramadan Olfat A. Khalil Enas N. Danial Hanan S. Alnahdi Najla O. Ayaz 《Journal of physiology and biochemistry》2013,69(4):779-783
The present study examined the effect of water extract (200 mg/kg body weight) of Rosmarinus officinalis L. in streptozotocin (STZ)-induced diabetic rats for 21 days. The hepatoprotective effects were investigated in the liver tissues sections. There was a significant increase in serum liver biochemical parameters (aspartate aminotransferase, alanine transaminase, and alkaline phosphatase), accompanied by a significant decrease in the level of total protein and albumin in the STZ-induced rats when compared with that of the normal group. The high-dose treatment group (200 mg/kg body wt) significantly restored the elevated liver function enzymes near to normal. This study revealed that rosemary extracts exerted a hepatoprotective effect. The results indicate that the extract exhibits the protective effect on tissues and prove its potentials as an antidiabetic agent. 相似文献
23.
Andrea Szuchman Michael Aviram Ramadan Musa Soliman Khatib Professor Jacob Vaya 《Biomarkers》2013,18(1):119-131
In the present study, we extend our novel concept of designing and using exogenous markers for the characterization of oxidative stress (OS) and OS-associated diseases. The aim was to use such a synthetic compound as a tool for studying OS in blood from diabetic and hypercholesterolaemic (Hc) patients. The marker used N-linoleoyl tyrosine (LT) was constructed from tyrosine and linoleic acid (LA); both components are known to be easily oxidized upon exposure to different types of reactive oxygen/nitrogen species (ROS/RNS), and to generate specific oxidized products, depending on the type of oxidants present in vivo. Using the LT probe, we showed that the ratios of oxidized LT to total LT (Ox-LT/LT) is significantly higher in blood samples obtained from diabetic patients, than in Hc patients or healthy control subjects. LC/MS analysis revealed that blood from diabetic patients oxidizes the marker with predominant formation of Ox-LT hydroperoxide (LT-OOH) and epoxide (epoxy-LT), where the LA moiety is oxidized to hydroperoxide and to epoxide, respectively. Analysis of oxysterol levels in these samples (GC/MS) revealed that the blood of both diabetic and Hc patients contained significantly more oxysterols than blood of control subjects. Consumption of pomegranate juice by diabetic patients for 3 months suppressed their blood capacity to oxidize the LT and similarly also reduced their blood oxysterol/total cholesterol ratio by 93%. The use of an exogenous marker to characterize OS in blood samples yields important information on the extent of OS, and can provide a fingerprint for the early identification of different pathological conditions associated with OS. 相似文献
24.
25.
Ahmed Hashim Toshiharu Abe Lijian Jin Yucheng Chang Zhi Chao Jin Jian Xun Sun George Hajishengallis Mike A. Curtis Richard P. Darveau 《Cellular microbiology》2013,15(8):1419-1426
The oral and intestinal host tissues both carry a heavy microbial burden. Although commensal bacteria contribute to healthy intestinal tissue structure and function, their contribution to oral health is poorly understood. A crucial component of periodontal health is the recruitment of neutrophils to periodontal tissue. To elucidate this process, gingival tissues of specific‐pathogen‐free and germ‐free wild‐type mice and CXCR2KO and MyD88KO mice were examined for quantitative analysis of neutrophils and CXCR2 chemoattractants (CXCL1, CXCL2). We show that the recruitment ofneutrophils to the gingival tissue does not require commensal bacterial colonization but is entirely dependent on CXCR2 expression. Strikingly, however, commensal bacteria selectively upregulate the expression of CXCL2, but not CXCL1, in a MyD88‐dependent way that correlates with increased neutrophil recruitment as compared with germ‐free conditions. This is the first evidence that the selective use of chemokine receptor ligands contributes to neutrophil homing to healthy periodontal tissue. 相似文献
26.
Faiqah Ramli Mawardi Rahmani Nur Kartinee Kassim Najihah Mohd Hashim Mohd Aspollah Sukari Abdah Md Akim Rusea Go 《Phytochemistry letters》2013,6(4):582-585
Two new diprenylated dihydrochalcones, elastichalcone A 1 and elastichalcone B 2 and three known compounds were isolated from the leaves of Artocarpus elasticus. Their structures were determined by various spectroscopic techniques (UV, IR, MS, 1D-NMR and 2D-NMR). Elastichalcone B 2 and a known compound exhibited good free radical scavenging activity with IC50 values of 11.30 and 11.89 μg/ml, respectively. 相似文献
27.
Saidi H. Kapiga Fiona M. Ewings Tony Ao Joseph Chilongani Aika Mongi Kathy Baisley Suzanna Francis Aura Andreasen Ramadhan Hashim Deborah Watson-Jones John Changalucha Richard Hayes 《PloS one》2013,8(7)
Objectives
To prepare for future HIV prevention trials, we conducted prospective cohort studies among women working in food and recreational facilities in northern Tanzania. We examined the prevalence and incidence of HIV and HSV-2, and associated risk factors.Methods
Women aged 18–44 years working in food and recreational facilities were screened to determine their eligibility for the studies. Between 2008–2010, HIV-negative women were enrolled and followed for 12 months. At enrolment and 3-monthly, we collected socio-demographic and behavioural data, and performed clinical examinations for collection of biological specimens that were tested for reproductive tract infections. Risk factors for HIV and HSV-2 incidence were investigated using Poisson regression models.Results
We screened 2,229 and enrolled 1,378 women. The median age was 27 years (interquartile range, IQR 22, 33), and median duration working at current facility was 2 years. The prevalences of HIV at screening and HSV-2 at enrolment were 16% and 67%, respectively. Attendance at the 12-month visit was 86%. HIV and HSV-2 incidence rates were 3.7 (95% confidence interval, CI: 2.8,5.1) and 28.6 (95% CI: 23.5,35.0)/100 person-years, respectively. Women who were separated, divorced, or widowed were at increased risk of HIV (adjusted incidence rate ratio, aRR = 6.63; 95% CI: 1.97,22.2) and HSV-2 (aRR = 2.00; 95% CI: 1.15,3.47) compared with married women. Women reporting ≥3 partners in the past 3 months were at higher HIV risk compared with women with 0–1 partner (aRR = 4.75; 95% CI: 2.10,10.8), while those who had reached secondary education or above were at lower risk of HSV-2 compared with women with incomplete primary education (aRR = 0.42; 95% CI: 0.22,0.82).Conclusions
HIV and HSV-2 rates remain substantially higher in this cohort than in the general population, indicating urgent need for effective interventions. These studies demonstrate the feasibility of conducting trials to test new interventions in this highly-mobile population. 相似文献28.
Muwaffaq Ramadan Karajeh 《Archives Of Phytopathology And Plant Protection》2013,46(20):2492-2500
Saccharomyces cerevisiae is a promising plant growth-promoting yeast for different crops. Applicability of S. cerevisiae as a biocontrol agent of the root-knot nematode (Meloidogyne javanica) was investigated on cucumber under growth-room and field conditions. The yeast S. cerevisiae similar to the nematicide, Ethoprophos, when applied as a rhizospheric soil drench treatment led to an obvious reduction of root galling caused by M. javanica and resulted in reducing the nematode reproduction ability on cucumber under growth room and field conditions. The yeast was more effective at 10 than at 5?g/l. Furthermore, the application of S. cerevisiae resulted in improving cucumber plant growth and increasing its fruit yield. High content of total phenolics in cucumber roots of S. cerevisiae-treated plants and hydrogen peroxide-treated plants gives a clue on the ability of the yeast to induced plant resistance in a similar way to exogenous hydrogen peroxide. 相似文献
29.
Sarah Catherine Hill Talal Ramadan Mohammad Toomas Kivisild 《American journal of physical anthropology》2013,152(1):140-144
Lactase persistence (LP)—the ability to digest lactose in adulthood—is paradigmatic of Holocenic dietary change affecting the evolutionary trajectory of specific populations. Kuwait represents one location of high LP where the variation in associated genomic regions has not been examined. Here, we present new sequence data from a 427 bp amplicon 14 kb upstream of the LCT (lactase) gene for two Bedouin tribal populations, the Ajman and Mutran. We estimate the frequency of known LP associated alleles and discuss the impact of nomadic‐pastoralism on the associated genetic variation. We observe high frequency (56% on average) of the ?13,915*G allele in both tribes, which is consistent with the high prevalence of LP in Kuwait. Whilst LP associated alleles occur in Kuwait at a similar frequency to other regional populations, we suggest that the ?13,915*G allele frequency among the Kuwaiti Bedouin may be higher than among non‐Bedouin Kuwaitis, possibly due to greater historical reliance on milk consumption or genetic drift. Am J Phys Anthropol 152:140–144, 2013. © 2013 Wiley Periodicals, Inc. 相似文献
30.
Cheng-Siang Lee Nur Aishah Mohd Taib Ali Ashrafzadeh Farhana Fadzli Faizah Harun Kartini Rahmat See Mee Hoong Puteri Shafinaz Abdul-Rahman Onn Haji Hashim 《PloS one》2016,11(2)
Heavily glycosylated mucin glycopeptides such as CA 27.29 and CA 15–3 are currently being used as biomarkers for detection and monitoring of breast cancer. However, they are not well detected at the early stages of the cancer. In the present study, perchloric acid (PCA) was used to enhance detection of mucin-type O-glycosylated proteins in the serum in an attempt to identify new biomarkers for early stage breast cancer. Sensitivity and specificity of an earlier developed sandwich enzyme-linked lectin assay were significantly improved with the use of serum PCA isolates. When a pilot case-control study was performed using the serum PCA isolates of normal participants (n = 105) and patients with stage 0 (n = 31) and stage I (n = 48) breast cancer, higher levels of total O-glycosylated proteins in sera of both groups of early stage breast cancer patients compared to the normal control women were demonstrated. Further analysis by gel-based proteomics detected significant inverse altered abundance of proteoglycan 4 and plasma protease C1 inhibitor in both the early stages of breast cancer patients compared to the controls. Our data suggests that the ratio of serum proteoglycan 4 to protease C1 inhibitor may be used for screening of early breast cancer although this requires further validation in clinically representative populations. 相似文献