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681.
Norzana Abd Ghafar Kien Hui Chua Wan Zurinah Wan Ngah Jemaima Che Hamzah Fauziah Othman Ropilah Abd Rahman Ruszymah Hj Idrus 《Cell and tissue banking》2014,15(1):25-34
The in vivo quiescent corneal stroma keratocytes need to be transformed to activated state in order to obtain sufficient number of cells either for monolayer evaluation or corneal stroma reconstruction. This study aimed to investigate the phenotypic characterization of corneal stromal cells during culture expansion from the limbal region of the cornea. Isolated corneal keratocytes from limbal tissue of New Zealand White Strain rabbits’ corneas (n = 6) were culture expanded until three passages. Keratocytes morphology was examined daily with viability, growth rate, number of cell doubling and population doubling time were recorded at each passage. The expression of collagen type 1, aldehyde dehydrogenase (ALDH), lumican and alpha smooth muscle actin (α-SMA) were detected by RT-PCR. Immunocytochemistry was also used to detect ALDH, α-SMA, collagen type I and Cytokeratin-3 (CK3). Growth kinetic study revealed that the growth rate was low at the initial passage but increase to about two folds with concomitant reduction in population doubling time in later passages. Freshly isolated and cultured keratocytes expressed collagen type 1, ALDH and lumican but α-SMA expression was absent. However, α-SMA was expressed along with the other genes during culture expansion. Keratocytes at P1 expressed all the proteins except CK3. These results suggest that cultured keratocytes maintained most of the gene expression profile of native keratocytes while the emergence of α-SMA in serial passages showed a mix population of various phenotypes. The phenotypic characterization of monolayer keratocytes provides useful information before reconstruction of bioengineered tissue or in vitro pharmaceutical applications. 相似文献
682.
High‐Throughput Quantitation of Intracellular Trafficking and Organelle Disruption by Flow Cytometry
Pei Zhi Cheryl Chia Yasmin M. Ramdzan Fiona J. Houghton Danny M. Hatters Paul A. Gleeson 《Traffic (Copenhagen, Denmark)》2014,15(5):572-582
Current methods for the quantitation of membrane protein trafficking rely heavily on microscopy, which has limited quantitative capacity for analyses of cell populations and is cumbersome to perform. Here we describe a simple flow cytometry‐based method that circumvents these limitations. The method utilizes fluorescent pulse‐width measurements as a highly sensitive indicator to monitor the changes in intracellular distributions of a fluorescently labelled molecule in a cell. Pulse‐width analysis enabled us to discriminate cells with target proteins in different intracellular locations including Golgi, lyso‐endosomal network and the plasma membrane, as well as detecting morphological changes in organelles such as Golgi perturbation. The movement of endogenous and exogenous retrograde cargo was tracked from the plasma membrane‐to‐endosomes‐to‐Golgi, by decreasing pulse‐width values. A block in transport upon RNAi‐mediated ablation of transport machinery was readily quantified, demonstrating the versatility of this technique to identify pathway inhibitors. We also showed that pulse‐width can be exploited to sort and recover cells based on different intracellular staining patterns, e.g. early endosomes and Golgi, opening up novel downstream applications. Overall, the method provides new capabilities for viewing membrane transport in thousands of cells per minute, unbiased analysis of the trafficking of cargo, and the potential for rapid screening of inhibitors of trafficking pathways. 相似文献
683.
Landa Zeenelabdin Ali Salim Rozana Othman Mahmood Ameen Abdulla Karim Al-Jashamy Hapipah Mohd Ali Pouya Hassandarvish Firouzeh Dehghan Mohamed Yousif Ibrahim Fatima Abd Elmutaal Ahmed Omer Syam Mohan 《PloS one》2014,9(12)
BackgroundThymoquinone is an active ingredient isolated from Nigella sativa (Black Seed). This study aimed to evaluate the in vitro and in vivo anti-leukemic effects of thymoquinone on WEHI-3 cells.ConclusionThymoquinone promoted natural killer cell activities. This compound showed high toxicity against WEHI-3 cell line which was confirmed by an increase of the early apoptosis, followed by up-regulation of the anti-apoptotic protein, Bcl2, and down-regulation of the apoptotic protein, Bax. On the other hand, high reduction of the spleen and liver weight, and significant histopathology study of spleen and liver confirmed that thymoquinone inhibited WEHI-3 growth in the BALB/c mice. Results from this study highlight the potential of thymoquinone to be developed as an anti-leukemic agent. 相似文献
684.
Liliane Chung Dalan Bailey Eoin N. Leen Edward P. Emmott Yasmin Chaudhry Lisa O. Roberts Stephen Curry Nicolas Locker Ian G. Goodfellow 《The Journal of biological chemistry》2014,289(31):21738-21750
Viruses have evolved a variety of mechanisms to usurp the host cell translation machinery to enable translation of the viral genome in the presence of high levels of cellular mRNAs. Noroviruses, a major cause of gastroenteritis in man, have evolved a mechanism that relies on the interaction of translation initiation factors with the virus-encoded VPg protein covalently linked to the 5′ end of the viral RNA. To further characterize this novel mechanism of translation initiation, we have used proteomics to identify the components of the norovirus translation initiation factor complex. This approach revealed that VPg binds directly to the eIF4F complex, with a high affinity interaction occurring between VPg and eIF4G. Mutational analyses indicated that the C-terminal region of VPg is important for the VPg-eIF4G interaction; viruses with mutations that alter or disrupt this interaction are debilitated or non-viable. Our results shed new light on the unusual mechanisms of protein-directed translation initiation. 相似文献
685.
Saiful Anuar Karsani Iekhsan Othman 《Biochemical and biophysical research communications》2009,389(2):343-348
The Malayan krait (Bungarus candidus) is one of the medically most important snake species in Southeast Asia. The venom from this snake has been shown to posses both presynaptic and post-synaptic neurotoxins. We have isolated a previously uncharacterized post-synaptic neurotoxin - alphaN3 from the venom of B. candidus. Isolation of the toxin was achieved in three successive chromatography steps - gel filtration on a Sephadex G75 column, followed by ion exchange chromatography (Mono-S strong cationic exchanger) and a final reverse-phase chromatography step (PRO-RPC C18 column). Purified toxin alphaN3 was shown to have an apparent molecular weight of ∼7 to 8 kDa on SDS-PAGE. The complete amino acid sequence of toxin alphaN3 was determined by Edman degradation and was found to share a high degree of homology with known post-synaptic neurotoxins (93% with alpha-bungarotoxin from Bungarus multicinctus, 50% with alpha cobratoxin from Naja kaouthia). The intravenous LD50 of toxin alphaN3 was determined to be 0.16 ± 0.09 μg/g in mice which is comparable to alpha-bungarotoxin from B. multicinctus. Experiments with isolated nerve-muscle preparations suggested that toxin alphaN3 was a post-synaptic neurotoxin that produced complete blockade of neuromuscular transmission by binding to nicotinic acetylcholine receptors. 相似文献
686.
Adel M. Ghanem Khaled N. Al-Ruwis Safar H. Alqahtani Othman S. Al-Nashwan Abdul-Aziz M. Al-Duwais Mohamad A. Alnafissa Jawad Alhashem Sahar A. Kamara Sharafeldin B. Alaagib Nageeb M. Aldawdahi 《Saudi Journal of Biological Sciences》2021,28(8):4825-4832
This study aimed to identify the economic dimension of directing treated wastewater to the production of green fodder. To achieve its objectives, the study relied on economic equations, the method of using multiple criteria, and a scoring technique for prioritization. The study showed that green fodder is a crop that depletes water, as it consumes about 67.27% of the water used for agricultural purposes. In determining the priority of regions intending to use treated wastewater, the ranking put Riyadh region first, followed by the eastern region, the Qassim region, Hail, Makkah Al-Mukarramah, Tabuk, Asir, Al-Jawf, Jizan, Madinah, Najran, the northern borders, and Al-Baha, in this order. The area that can be cultivated with forage crops is estimated to be about 53.05 thousand hectares, with a production of 953.75 thousand tons. The cost of treating wastewater to make it usable amounts to 2126.22 million riyals, while the value of the benefits gained from its use is 2508.95 million riyals; thus, the Saudi agricultural economy achieves a net gain estimated at about 382.73 million riyals annually. Therefore, this study recommends the use of treated wastewater in the production of green fodder. 相似文献
687.
Sjöling A Qadri F Nicklasson M Begum YA Wiklund G Svennerholm AM 《Microbes and infection / Institut Pasteur》2006,8(12-13):2797-2802
Enterotoxigenic Escherichia coli (ETEC) colonize the intestine and adhere to the epithelium by means of different host specific colonization factors (CFs). Colonizing ETEC produce one or both of two enterotoxins; the heat stable (ST) and heat labile (LT) toxins which are both able to cause diarrhoea. The regulation of virulence genes in ETEC during infection of the human intestine is mainly unknown. In this study we analysed the level of mRNA expression of estA, coding for ST, and eltB, coding for the B subunit of LT, during human infection. The expressions of the toxins in ETEC strains expressing both ST and LT were investigated in bacteria isolated directly from patient stool without sub-culturing, (in vivo) and compared to the expression pattern of the corresponding ST/LT strains grown in liquid broth (in vitro) by quantitative competitive RT-PCR using fluorescent primers. We found that estA and eltB are expressed in the in vivo samples but no significant up-or down regulation of the expression levels of either estA or eltB could be determined in vivo as compared to in vitro. 相似文献
688.
McTiernan A Wu L Chen C Chlebowski R Mossavar-Rahmani Y Modugno F Perri MG Stanczyk FZ Van Horn L Wang CY;Women's Health Initiative Investigators 《Obesity (Silver Spring, Md.)》2006,14(9):1662-1677
Objective: Levels of estrogen, androgen, and prolactin have been related to risk of postmenopausal breast cancer. However, the determinants of these hormone concentrations are not established. The purpose of this study was to examine correlates of endogenous sex hormones. Research Methods and Procedures: Associations among adiposity, physical activity, and diet and concentrations of estradiol, free estradiol, estrone, testosterone, free testosterone, sex hormone‐binding globulin (SHBG), androstenedione, dehydroepiandrosterone, dehydroepiandrosterone sulfate, and prolactin were evaluated in 267 postmenopausal women randomly selected from the Women's Health Initiative Dietary Modification Trial. Results: In multiple regression analyses on log‐transformed hormones, BMI was positively associated with estrone (β = 0.031, p < 0.001), estradiol (β = 0.048, p < 0.001), free estradiol (β = 0.062, p < 0.001), free testosterone (β = 0.017, p = 0.02), and prolactin (β = 0.012, p = 0.02) and negatively associated with SHBG (β = ?0.02, p = 0.001). Total physical activity (metabolic equivalent tasks per week) was negatively associated with concentrations of estrone, estradiol, and androstenedione (β = ?0.006, ?0.007, and ?0.005, respectively, all p ≤ 0.05). Using a composite variable of BMI and physical activity dichotomized by median values, women with high BMI/low physical activity had a mean estrone concentration of 28.8 pg/mL, compared with 24.1, 19.9, and 18.4 pg/mL for women with high BMI/high physical activity, low BMI/low physical activity, and low BMI/high physical activity, respectively (p trend < 0.001). Similar trends were observed for estradiol and free estradiol and, in inverse, for SHBG. Discussion: These associations may, in part, explain the positive associations between overweight/obesity and a sedentary lifestyle on breast cancer risk. 相似文献
689.
Simone Wörtge Leonid Eshkind Nina Cabezas-Wallscheid Bernard Lakaye Jinhyun Kim Rosario Heck Yasmin Abassi Mustafa Diken Rolf Sprengel Ernesto Bockamp 《BMC developmental biology》2010,10(1):95
Background
Conditional gene activation is an efficient strategy for studying gene function in genetically modified animals. Among the presently available gene switches, the tetracycline-regulated system has attracted considerable interest because of its unique potential for reversible and adjustable gene regulation. 相似文献690.
Othman Wan-Norafikah Wasi Ahmad Nazni Han Lim Lee Pawanchee Zainol-Ariffin Mohd Sofian-Azirun 《Journal of Asia》2010,13(3):175-182
Permethrin resistance status of a laboratory strain, a permethrin-selected strain and three field strains of Aedes aegypti collected in Kuala Lumpur, Malaysia were evaluated using three standard laboratory bioassays: WHO larval bioassay, WHO adult mosquito bioassay, and mixed function oxidase (MFO) enzyme microassay. The LC50 values of field strains from the WHO larval bioassay did not differ significantly. The highest LC50 value was from the Taman Melati field strain (0.39 mg/L). The resistance ratio for the permethrin-selected strain and the field strains ranged from 1.86 fold to 5.57 fold. Pre-exposure to piperonyl butoxide (PBO) in the WHO adult bioassay and MFOs enzyme microassay reduced the LT50 values and reduced the mean optical density of elevated oxidase activity (0.28–0.42) at 630 nm. The LC50 or LT50 values and the level of oxidases were significantly correlated (r = 0.825; p< 0.05). This study confirmed the presence of permethrin resistance in these mosquito populations. 相似文献