Comparison of the Adhesion and Proliferation Characteristics of HUVEC and Two Endothelial Cell Lines (CRL 2922 and CRL 2873) on Various Substrata

Boon Chin Heng,Yun Xia,Xiaobo Shang,Peter Rainer Preiser,S. K. Alex Law,Freddy Yin-Chiang Boey,Subbu S. Venkatraman 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.1

Endothelial cell coverage of blood-contacting devices is crucial to their eventual success in the clinic. Two established human cell lines derived from HUVEC (human umbilical vascular endothelial cells), CRL 2922and CRL 2873, have been widely utilized to study and model endothelial cell biology. However, it is not clear if these two cell lines would be useful for modeling primary endothelial cell interaction with newly-formulated biomaterials in tissue engineering applications. Hence, this study was conducted to compare the adhesion and proliferation characteristics of HUVEC grown on seven different substrata, tissue culture polystyrene (TCPS), gelatin,chitosan, poly-L-lysine, hyaluronan, poly-L-lactic acid (PLLA), and polylactic-co-glycolic acid (PLGA). The short-term adhesive behavior (2 h) of HUVEC on the various substrata was not closely-replicated by either CRL 2873 or CRL 2922. This was likely because the 2 h timeframe is too short for identification of differences in the interaction among the three cell types grown on various substrata. There was much faster proliferation of CRL 2922 on all seven substrata when compared to HUVEC and CRL 2873. Moreover, the proliferation rates of CRL 2922 on the various substrata showed little variation. In contrast, HUVEC and CRL 2873 displayed similar trends in proliferation rates, with gelatin and TCPS yielding the highest rates, and PLLA and PLGA yielding the lowest rates. Hence, CRL 2873 is better suited for modeling primary endothelial cell interaction with newly-formulated biomaterials than CRL 2922. The advantage of using CRL 2873 over HUVEC for biomaterial screening is that it is immortalized and displays much less inter-batch variability than primary culture.

Lack of Correlation of Sinonasal and Otologic Reported Symptoms With Objective Measurements Among Patients With Primary Ciliary Dyskinesia: An International Study

Yin Ting Lam,Myrofora Goutaki,Jean-François Papon,Mihaela Alexandru,Andreas Anagiotos,Miguel Armengot,Mieke Boon,Andrea Burgess,Nathalie Caversaccio,Suzanne Crowley,Sinan Ahmed D. Dheyauldeen,Nagehan 대한이비인후과학회 2023 Clinical and Experimental Otorhinolaryngology Vol.16 No.4

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Lactobacillus plantarum DR7 Reduces Cholesterol via Phosphorylation of AMPK That Down-regulatedthe mRNA Expression of HMG-CoA Reductase

Lee-ching Lew,Sy-bing Choi,Boon-yin Khoo,Sasidharan Sreenivasan,Kee-leong Ong,Min-tze Liong 한국축산식품학회 2018 한국축산식품학회지 Vol.38 No.2

Hypercholesterolemia is one of the primary risk factors for cardiovascular diseases. The use of lactobacilli probiotics to reduce blood cholesterol levels have been extensively reported. However, more information is needed to evaluate the possible mechanisms involved and to identify possible targets for further therapeutic development. In this study, strains of lactobacilli were screened based on the ability to assimilate cholesterol, and prevention of cholesterol accumulation in hepatic (HepG2) and intestinal (HT-29) cells. Cell free supernatant (CFS) from Lactobacillus plantarum DR7 showed a higher ability to assimilate cholesterol, reduction in cholesterol accumulation in both HepG2 and HT-29 cells, accompanied by reduced mRNA expression of HMG-CoA reductase (HMGCR) in HepG2 (p<0.05), compared to other lactobacilli. The reduction of HMGCR expression was also diminished in the presence of an AMPK inhibitor (Compound C), suggesting that L. plantarum DR7 exerted its effect via the AMPK pathway, typically via the phosphorylation of AMPK instead of the AMPK mRNA expression in HepG2 (p<0.05). Altogether, our present study illustrated that lactobacilli could exert cholesterol lowering properties along the AMPK pathway, specifically via phosphorylation of AMPK that led to reduced expression of HMGCR.

Lactobacillus Strains Alleviated Aging Symptoms and Aging-Induced Metabolic Disorders in Aged Rats

HOR YAN YAN,Cheong-Hwa Ooi,Boon-Yin Khoo,Sy-Bing Choi,Azman Seeni,Shaharum Shamsuddin,Chern-Ein Oon,Kee-Leong Ong,정우식,Min-Tze Liong 한국식품영양과학회 2019 Journal of medicinal food Vol.22 No.1

Aging is an inevitable and ubiquitous progress that affects all living organisms. A total of 18 strains of lactic acid bacteria (LAB) were evaluated on the activation of adenosine monophosphate-activated protein kinase (AMPK), an intracellular energy sensor mediating lifespan extension. The cell-free supernatant (CFS) of Lactobacillus fermentum DR9 (LF-DR9), Lactobacillus paracasei OFS 0291 (LP-0291), and Lactobacillus helveticus OFS 1515 (LH-1515) showed the highest activation of AMPK and was further evaluated. The phosphorylation of AMPK by these three LAB strains was more evident in U2OS and C2C12 cells, compared to the other cell lines and control (P < .05). Using premature senescent Sprague-Dawley rats induced by D-galactose (D-gal), the administration of LAB (10 log CFU/rat/day) for 12 weeks prevented the shortening of telomere length in D-gal-treated rats compared to the untreated control (P < .05). LF-DR9 lowered gene expression of p53, a known senescent biomarker, in gastrocnemius muscle and tibia compared to the control. The selected LAB strains also enhanced lipid, renal, and liver profile of rats, suggesting added potential of the strains in preventing aging-induced metabolic diseases. Strain LP-0291 and LH-1515 showed ability to adhere to mucin, no antibiotic resistance, tolerated and proliferated under gastric and intestinal simulated conditions, and inhibited the growth of pathogens Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis, comparable to commercial probiotic LF-DR9 and Lactobacillus sakei Probio 65. This study provided an insight into the potential of LAB for exhibiting antisenescence effects, with potentials as new medicinal foods for targeted antiaging therapies.

Lyme Disease and YouTubeTM: A Cross-Sectional Study of Video Contents

Corey H. Basch,Lindsay A. Mullican,Kwanza D. Boone,Jingjing Yin,Alyssa Berdnik,Marina E. Eremeeva,Isaac Chun-Hai Fung 질병관리본부 2017 Osong Public Health and Research Persptectives Vol.8 No.4

Objectives: Lyme disease is the most common tick-borne disease. People seek health information on Lyme disease from YouTubeTM videos. In this study, we investigated if the contents of Lyme disease-related YouTubeTM videos varied by their sources. Methods: Most viewed English YouTubeTM videos (n = 100) were identified and manually coded for contents and sources. Results: Within the sample, 40 videos were consumer-generated, 31 were internet-based news, 16 were professional, and 13 were TV news. Compared with consumer-generated videos, TV news videos were more likely to mention celebrities (odds ratio [OR], 10.57; 95% confidence interval [CI], 2.13–52.58), prevention of Lyme disease through wearing protective clothing (OR, 5.63; 95% CI, 1.23–25.76), and spraying insecticides (OR, 7.71; 95% CI, 1.52–39.05). Conclusion: A majority of the most popular Lyme disease-related YouTubeTM videos were not created by public health professionals. Responsible reporting and creative video-making facilitate Lyme disease education. Partnership with YouTubeTM celebrities to co-develop educational videos may be a future direction.

Prospective application of Pichia pastoris-expressed DNA topoisomerase I in DNA relaxation assay for growth inhibitor screening

Chan Mooi Kwai,Wai Wen Xuan,Ang Ruo Ping,Chew Ai Lan,Khoo Boon Yin 한국미생물학회 2020 미생물학회지 Vol.56 No.1

The expression of in-house DNA topoisomerase I (Topo1) was optimized in order to develop a gel-based DNA relaxation assay for the screening of potential bioactive compounds. Results showed that nearly 4-fold increment in total protein level was achieved in the culture supernatant with 1.0% (v/v) methanol feeding every 24 h and cultivated for 72 h at 28°C. Crude recombinant TopoI was shown to relax the supercoiled plasmid DNA completely in the developed gel-based assay and reactions were not affected by DMSO addition and the features on electrophoresed gel could be improved by chloroform: isoamylalcohol extraction. The recombinant protein was then purified and the enzymatic activity of the recombinant TopoI in the crude and purified culture supernatant was studied and compared with a commercial TopoI. DNA relaxation assay showed that the purified recombinant TopoI is a more reliable source with an activity of approximately 20~30 U/μl. The developed assay was finally evaluated by determining the inhibitory effects of flavonoids and positive control Camptothecin on the recombinant TopoI catalytic activity. The efficiency of the gel-based assay using purified recombinant TopoI was further evaluated against a cell-based cytotoxicity assay in which the inhibitory effects on cell growth by the flavonoids and Camptothecin were assessed. The similar inhibitory trends shown by both assays demonstrated that potential inhibitors can be preliminarily screened using a gel-based assay prior to identification of the inhibitors using a cell-based assay to detect the DNA intercalating agents that interrupt the TopoI catalytic activity.