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Fulltext DNA mismatch repair and CD133-marked cancer stem cells in colorectal carcinoma

Cheah PL, Li J, Looi LM, Teoh KH, Ong DB, Arends MJ

PeerJ, 2018;6:e5530.
PMID: 30221090 DOI: 10.7717/peerj.5530

Background: Except for a few studies with contradictory observations, information is lacking on the possibility of association between DNA mismatch repair (MMR) status and the presence of cancer stem cells in colorectal carcinoma (CRC), two important aspects in colorectal carcinogenesis.
Methods: Eighty (40 right-sided and 40 left-sided) formalin-fixed, paraffin-embedded primary CRC were immunohistochemically studied for CD133, a putative CRC stem cell marker, and MMR proteins MLH1, MSH2, MSH6 and PMS2. CD133 expression was semi-quantitated for proportion of tumor immunopositivity on a scale of 0-5 and staining intensity on a scale of 0-3 with a final score (units) being the product of proportion and intensity of tumor staining. The tumor was considered immunopositive only when the tumor demonstrated moderate to strong intensity of CD133 staining (a decision made after analysis of CD133 expression in normal colon). Deficient MMR (dMMR) was interpreted as unequivocal loss of tumor nuclear staining for any MMR protein despite immunoreactivity in the internal positive controls.
Results: CD133 was expressed in 36 (90.0%) left-sided and 28 (70.0%) right-sided tumors (p 0.05).
Conclusion: Proficient MMR correlated with high levels of CD133-marked putative cancer stem cells in both right- and left-sided tumors, whereas significantly lower levels of CD133-marked putative cancer stem cells were associated with deficient MMR status in colorectal carcinomas found on the right.

Matched MeSH terms: Neoplastic Stem Cells
Fulltext The role of miRNAs 34a, 146a, 320a and 542 in the synergistic anticancer effects of methyl 2-(5-fluoro-2-hydroxyphenyl)-1H- benzo[d]imidazole-5-carboxylate (MBIC) with doxorubicin in breast cancer cells

Hasanpourghadi M, Abdul Majid N, Rais Mustafa M

PeerJ, 2018;6:e5577.
PMID: 30245930 DOI: 10.7717/peerj.5577

Combination Index (CI) analysis suggested that MBIC and doxorubicin synergistically inhibited up to 97% of cell proliferation in ER+/PR+MCF-7 and triple negative MDA-MB-231 breast cancer cell lines. Moreover, treatment of the breast cancer cells with the combined drugs resulted in lower IC50 values in contrast to the individual drug treatment. Small noncoding microRNAs (miRNA) may function as non-mutational gene regulators at post-transcriptional level of protein synthesis. In the present study, the effect of the combined treatment of MBIC and doxorubicin on the expression level of several miRNAs including miR-34a, miR-146a, miR-320a and miR-542 were evaluated in MCF-7 and MDA-MB-231 breast cancer cell lines. These miRNAs have the potential to alter the protein level of survivin, the anti-apoptotic protein and reduce the metastatic activity in human breast cancer cell lines by interfering with the nuclear accumulation of NF-κB. Our results demonstrated the several fold changes in expression of miRNAs, which is drug and cell line dependent. This finding demonstrated a functional synergistic network between miR-34a, miR-320a and miR-542 that are negatively involved in post-transcriptional regulation of survivin in MCF-7 cells. While in MDA-MB-231 cells, changes in expression level of miR-146a was correlated with inhibition of the nuclear translocation of NF-κB. The overall result suggested that alteration in protein level and location of survivin and NF-κB by miR-34a, miR-320a, miR-146a and miR-542, remarkably influenced the synergistic enhancement of combined MBIC and doxorubicin in treatment of aggressive and less aggressive human breast cancer cell lines.

Matched MeSH terms: MCF-7 Cells
Fulltext Efficient production of succinic acid in immobilized fermentation with crude glycerol from Escherichia coli

Nik Nor Aziati, A.A., Mimi Sakinah, A.M.

Food Research, 2018;2(1):110-118.
MyJurnal

The increase in the price of commercial succinic acid has necessitated the need for its
synthesis from waste materials such as glycerol. Glycerol residue is a waste product of
Oleochemical production which is cheaply available and a very good source of carbon.
The use of immobilized cells can further reduce the overall cost of the production process.
This study primarily aims to produce succinic acid from glycerol residue through the use
of immobilized Escherichia coli in a batch fermentation process. The parameters which
affect bacterial fermentation process such as the mass substrate, temperature, inoculum
size and duration of fermentation were screened using One-Factor-At-a-Time (OFAT)
method. The result of the screening process shows that a substrate (glycerol) concentration
of 30 g, inoculum size 20% v/v, and time 4 h produced the maximum succinic acid
concentration of 117.99 g/L. The immobilized cells were found to be stable as well as
retain their fermentative ability up to the 6th cycle of recycling, thereby presenting as an
advantage over the free cell system. Therefore, conclude that using immobilized cells can
contribute immensely to the cost-effective production of succinic acid from glycerol
residue.

Matched MeSH terms: Cells, Immobilized
Fulltext Dendritic cells pulsed with generated tumor cell lysate from Phyllanthus amarus Schum. & Thonn. induces anti-tumor immune response

Mohamed SIA, Jantan I, Nafiah MA, Seyed MA, Chan KM

BMC Complement Altern Med, 2018 Aug 06;18(1):232.
PMID: 30081891 DOI: 10.1186/s12906-018-2296-4

BACKGROUND: Dendritic cells (DCs) are unique antigen presenting cells (APC) which play a pivotal role in immunotherapy and induction of an effective immune response against tumors. In the present study, 80% ethanol extract of Phyllanthus amarus was used to generate tumor lysate (TLY) derived from HCT 116 and MCF-7 cancer cell lines via induction of apoptosis. Monocyte-derived DCs were generated ex vivo from the adherent population of peripheral blood mononuclear cells (PBMCs). The generated TLY were used to impulse DCs to investigate its effect on their cellular immune functions including antigen presentation capacity, phagocytic activity, chemotaxis capacity, T-cell proliferation and cytokines release.
METHODS: The effect of P. amarus-generated TLY on DCs maturation was evaluated by determination of MHC class I, II and CD 11c expression as well as the co-stimulatory molecules CD 83 and 86 by using flow cytometry. The phagocytic capacity of TLY-pulsed DCs was investigated through FITC-dextran uptake by using flow cytometry. The effect on the cytokines release including IL-12, IL-6 and IL-10 was elucidated by using ELISA. The migration capacity and T cell proliferation activity of pulsed DCs were measured. The relative gene expression levels of cytokines were determined by using qRT-PCR. The major constituents of P. amarus extract were qualitatively and quantitatively analyzed by using validated reversed-phase high performance liquid chromatography (HPLC) methods.
RESULTS: P. amarus-generated TLY significantly up-regulated the expression levels of MHC class I, CD 11 c, CD 83 and 86 in pulsed DCs. The release of interleukin IL-12 and IL-6 was enhanced by TLY-DCs at a ratio of 1 DC: 3 tumor apoptotic bodies (APO), however, the release of IL-10 was suppressed. The migration ability as well as allogeneic T-cell proliferation activities of loaded DCs were significantly enhanced, but their phagocytic capacity was highly attenuated. The gene expression profiles for IL-12 and IL-6 of DCs showed increase in their mRNA gene expression in TLY pulsed DCs versus unloaded and LPS-treated only DCs.
CONCLUSION: The effect of P. amarus-generated TLY on the immune effector mechanisms of DCs verified its potential to induce an in vitro anti-tumor immune response against the recognized tumor antigen.

Matched MeSH terms: Cells, Cultured; Dendritic Cells/drug effects*; Dendritic Cells/immunology*
Fulltext Host Lipid Rafts Play a Major Role in Binding and Endocytosis of Influenza A Virus

Verma DK, Gupta D, Lal SK

Viruses, 2018 11 18;10(11).
PMID: 30453689 DOI: 10.3390/v10110650

Influenza still remains one of the most challenging diseases, posing a significant threat to public health. Host lipid rafts play a critical role in influenza A virus (IAV) assembly and budding, however, their role in polyvalent IAV host binding and endocytosis had remained elusive until now. In the present study, we observed co-localization of IAV with a lipid raft marker ganglioside, GM1, on the host surface. Further, we isolated the lipid raft micro-domains from IAV infected cells and detected IAV protein in the raft fraction. Finally, raft disruption using Methyl-β-Cyclodextrin revealed significant reduction in IAV host binding, suggesting utilization of host rafts for polyvalent binding on the host cell surface. In addition to this, cyclodextrin mediated inhibition of raft-dependent endocytosis showed significantly reduced IAV internalization. Interestingly, exposure of cells to cyclodextrin two hours post-IAV binding showed no such reduction in IAV entry, indicating use of raft-dependent endocytosis for host entry. In summary, this study demonstrates that host lipid rafts are selected by IAV as a host attachment factors for multivalent binding, and IAV utilizes these micro-domains to exploit raft-dependent endocytosis for host internalization, a virus entry route previously unknown for IAV.

Matched MeSH terms: A549 Cells
Fulltext Ultrasmall superparamagnetic Fe3O4 nanoparticles: honey-based green and facile synthesis and in vitro viability assay

Rasouli E, Basirun WJ, Rezayi M, Shameli K, Nourmohammadi E, Khandanlou R, et al.

Int J Nanomedicine, 2018;13:6903-6911.
PMID: 30498350 DOI: 10.2147/IJN.S158083

Introduction: In the present research, we report a quick and green synthesis of magnetite nanoparticles (Fe3O4-NPs) in aqueous solution using ferric and ferrous chloride, with different percentages of natural honey (0.5%, 1.0%, 3.0% and 5.0% w/v) as the precursors, stabilizer, reducing and capping agent, respectively. The effect of the stabilizer on the magnetic properties and size of Fe3O4-NPs was also studied.
Methods: The nanoparticles were characterized by X-ray diffraction (XRD) analysis, field emission scanning electron microscopy, energy dispersive X-ray fluorescence, transmission electron microscopy (TEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy.
Results: The XRD analysis indicated the presence of pure Fe3O4-NPs while the TEM images indicated that the Fe3O4-NPs are spherical with a diameter range between 3.21 and 2.22 nm. The VSM study demonstrated that the magnetic properties were enhanced with the decrease in the percentage of honey. In vitro viability evaluation of Fe3O4-NPs performed by using the MTT assay on the WEHI164 cells demonstrated no significant toxicity in higher concentration up to 140.0 ppm, which allows them to be used in some biological applications such as drug delivery.
Conclusion: The presented synthesis method can be used for the controlled synthesis of Fe3O4-NPs, which could be found to be important in applications in biotechnology, biosensor and biomedicine, magnetic resonance imaging and catalysis.

Matched MeSH terms: Tumor Cells, Cultured
Fulltext Enhancement of a protocol purifying T1 lipase through molecular approach

Che Hussian CHA, Raja Abd Rahman RNZ, Thean Chor AL, Salleh AB, Mohamad Ali MS

PeerJ, 2018;6:e5833.
PMID: 30479887 DOI: 10.7717/peerj.5833

T1 Lipase is a thermostable secretary protein of Geobacillus zalihae strain previously expressed in a prokaryotic system and purified using three-step purification: affinity 1, affinity 2, and ion exchange chromatography (IEX). This approach is time consuming and offers low purity and recovery yield. In order to enhance the purification strategy of T1 lipase, affinity 2 was removed so that after affinity 1, the cleaved Glutathione S-transferase (GST) and matured T1 lipase could be directly separated through IEX. Therefore, a rational design of GST isoelectric point (pI) was implemented by prediction using ExPASy software in order to enhance the differences of pI values between GST and matured T1 lipase. Site-directed mutagenesis at two locations flanking the downstream region of GST sequences (H215R and G213R) was successfully performed. Double point mutations changed the charge on GST from 6.10 to 6.53. The purified lipase from the new construct GST tag mutant-T1 was successfully purified using two steps of purification with 6,849 U/mg of lipase specific activity, 33% yield, and a 44-fold increase in purification. Hence, the increment of the pI values in the GST tag fusion T1 lipase resulted in a successful direct separation through IEX and lead to successful purification.

Matched MeSH terms: Prokaryotic Cells
Efficient differentiation of human ES and iPS cells into cardiomyocytes on biomaterials under xeno-free conditions

Sung TC, Liu CH, Huang WL, Lee YC, Kumar SS, Chang Y, et al.

Biomater Sci, 2019 Oct 28.
PMID: 31656967 DOI: 10.1039/c9bm00817a

Current xeno-free and chemically defined methods for the differentiation of hPSCs (human pluripotent stem cells) into cardiomyocytes are not efficient and are sometimes not reproducible. Therefore, it is necessary to develop reliable and efficient methods for the differentiation of hPSCs into cardiomyocytes for future use in cardiovascular research related to drug discovery, cardiotoxicity screening, and disease modeling. We evaluated two representative differentiation methods that were reported previously, and we further developed original, more efficient methods for the differentiation of hPSCs into cardiomyocytes under xeno-free, chemically defined conditions. The developed protocol successively differentiated hPSCs into cardiomyocytes, approximately 90-97% of which expressed the cardiac marker cTnT, with beating speeds and sarcomere lengths that were similar to those of a healthy adult human heart. The optimal cell culture biomaterials for the cardiac differentiation of hPSCs were also evaluated using extracellular matrix-mimetic material-coated dishes. Synthemax II-coated and Laminin-521-coated dishes were found to be the most effective and efficient biomaterials for the cardiac differentiation of hPSCs according to the observation of hPSC-derived cardiomyocytes with high survival ratios, high beating colony numbers, a similar beating frequency to that of a healthy adult human heart, high purity levels (high cTnT expression) and longer sarcomere lengths similar to those of a healthy adult human heart.

Matched MeSH terms: Pluripotent Stem Cells
Design, synthesis, and evaluation of novel diphenyl ether derivatives against drug-susceptible and drug-resistant strains of Mycobacterium tuberculosis

Kar SS, Bhat VG, Shenoy VP, Bairy I, Shenoy GG

Chem Biol Drug Des, 2019 01;93(1):60-66.
PMID: 30118192 DOI: 10.1111/cbdd.13379

In our efforts to develop druggable diphenyl ethers as potential antitubercular agents, a series of novel diphenyl ether derivatives (5a-f, 6a-f) were designed and synthesized. The representative compounds showed promising in vitro activity against drug-susceptible, isoniazid-resistant, and multidrug-resistant strains of Mycobacterium tuberculosis with MIC values of 1.56 μg/ml (6b), 6.25 μg/ml (6a-d), and 3.125 μg/ml (6b-c), respectively. All the synthesized compounds exhibited satisfactory safety profile (CC50 > 300 μg/ml) against Vero and HepG2 cells. Reverse phase HPLC method was used to probe the physicochemical properties of the synthesized compounds. This series of compounds demonstrated comparatively low logP values. pKa values of representative compounds indicated that they were weak acids. Additionally, in vitro human liver microsomal stability assay confirmed that the synthesized compounds possessed acceptable stability under study conditions. The present study thus establishes compound 6b as the most promising antitubercular agent with acceptable drug-likeness.

Matched MeSH terms: Hep G2 Cells
Gynura procumbens ethanol extract and its fractions inhibit macrophage derived foam cell formation

Manogaran M, Vuanghao L, Mohamed R

J Ethnopharmacol, 2020 Mar 01;249:112410.
PMID: 31747560 DOI: 10.1016/j.jep.2019.112410

ETHNOPHARMACOLOGY RELEVANCE: Gynura procumbens (Lour.) Merr. displayed cardio-protective effect that may prevent atherogenesis. The primary underlying pathological process of cardiovascular disease is atherosclerosis. Atherosclerotic lesion composed of macrophages, T cells and other immune cells which incorporated with cholesterol that infiltrates from the blood.
AIM OF THE STUDY: The present study was performed to determine underlying mechanism of G. procumbens ethanol extract and its fractions such as aqueous, chloroform, ethyl acetate and hexane affect macrophage derived foam cell formation.
MATERIALS AND METHODS: Lipid droplets accumulation in treated macrophages were visualized by Oil Red O staining while the total cholesterol present in the treated macrophages were measured using Cholestryl Ester quantification assay kit. Enzyme-Linked Immunosorbent Assay (ELISA) were used to detect TNF-α and IL-1β secretion in the supernatant of treated macrophages. Gene expression of Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) and ATP-binding cassette transporter A-1 (ABCA-1) in treated macrophages were analyzed using Real-Time Quantitative Polymerase Chain Reaction (RT-qPCR).
RESULTS: G. procumbens ethanol extract and its fractions reduced lipid droplet accumulation and total cholesterol in oxLDL-treated macrophages together with significantly reduction of TNF-α and IL-1β secretions in supernatant oxLDL-treated macrophages. LOX-1 gene expression was significantly reduced when G. procumbens ethanol extract and its fractions were added in oxDL-treated macrophages. In contrast, G. procumbens ethanol extract and its fractions significantly increased the expression of ABCA-1 gene in oxLDL-treated macrophages.
CONCLUSION: In conclusion, G. procumbens ethanol extract and its fractions inhibit the formation of macrophage derived foam cell by reducing TNF-α and IL-1β expression, which usually highly expressed in atherosclerotic plaques, suppressing scavenger receptor LOX-1 gene that binds oxLDL but induced ABCA-1 gene that mediate lipid efflux from macrophages.

Matched MeSH terms: RAW 264.7 Cells; Foam Cells/drug effects*; Foam Cells/metabolism
Fulltext Senescent HUVECs-secreted exosomes trigger endothelial barrier dysfunction in young endothelial cells

Wong PF, Tong KL, Jamal J, Khor ES, Lai SL, Mustafa MR

EXCLI J, 2019;18:764-776.
PMID: 31611757 DOI: 10.17179/excli2019-1505

Accumulation of senescent endothelial cells can cause endothelium dysfunction which eventually leads to age-related vascular disorders. The senescent-associated secretory phenotype (SASP) cells secrete a plethora of soluble factors that negatively influence the surrounding tissue microenvironment. The present study sought to investigate the effects of exosomes, which are nano-sized extracellular vesicles known for intercellular communications secreted by SASP cells on young endothelial cells. Exosomes were isolated from the condition media of senescent human umbilical vein endothelial cells (HUVECs) and then confirmed by the detection of exosome specific CD63 and CD9 expressions, electron microscopy and acetylcholinesterase assay. The purified exosomes were used to treat young HUVECs. Exposure to exosomes repressed the expression of adherens junction proteins including vascular endothelial (VE)-cadherin and beta-catenin, decreased cell growth kinetics and impaired endothelial migration potential of young endothelial cells. These findings suggest that senescent HUVECs-secreted exosomes could disrupt barrier integrity that underpins endothelial barrier dysfunction in healthy young endothelial cells.

Matched MeSH terms: Human Umbilical Vein Endothelial Cells
Fulltext Structural changes in the urinary bladder of streptozotocin-induced diabetic rats and the possible protective role of insulin

Elnagar, Amir M. Bassam, Suhaidah Ibrahim, Abouelnaga, Mostafa A.M., Soliman, Amro Mohamed

International Medical Journal Malaysia, 2018;17(3):39-48.
MyJurnal

Introduction: Diabetes mellitus possesses severe adverse effects on the urinary bladder. Urinary bladder dysfunction is a common health problem affecting diabetic patients causing recurrent infections and urinary incontinence. Objective: To evaluate the histopathological changes in the tissue of urinary bladder in Streptozotocin (STZ) diabetic rats and the protective role of insulin. Methods: Thirty rats were classified into three groups: a control group which received no treatment (Group A), STZ diabetic group (Group B) and Insulin diabetic group (Group C). Animals were sacrificed after six weeks and urinary bladders were harvested and processed for light and electron microscopy. Results: Several histopathological changes were observed in the urinary bladder of the diabetic group including an increase in the thickness of the urothelium, epithelial cells with dark nuclei and large lenticular vesicles, and wide intercellular spaces with numerous collagen fibers. Treatment with insulin reduced the pathological changes induced by STZ. Conclusion: Diabetes mellitus caused significant pathological changes in the urinary bladder of experimental rats. For instance, treating diabetic animals with insulin prevented the development of damaging effects of diabetes on the urinary bladder.

Matched MeSH terms: Epithelial Cells
Biomimetic hydroxyapatite/poly xylitol sebacic adibate/vitamin K nanocomposite for enhancing bone regeneration

Dai Z, Dang M, Zhang W, Murugan S, Teh SW, Pan H

Artif Cells Nanomed Biotechnol, 2019 Dec;47(1):1898-1907.
PMID: 31066314 DOI: 10.1080/21691401.2019.1573183

Hydroxyapatite (HAP) is a significant bone mineral that establishes bone strength. HAP composites in combination with biodegradable and bioactive polymer poly xylitol sebacic adipate (PXSA) would result in a constant release at target sites. Numerous studies have shown that vitamin K (VK) might possess a vital function in bone metabolism. The purpose of the present study was to inspect the synthesized composite HAP/PXSA/VK in developing polymeric biomaterials composite for the application of bone tissue regeneration. FTIR, X-ray diffraction, SEM and TEM techniques were applied to characterize the prepared composites. The release of VK from the HAP/PXSA/VK composite was evidenced through UV-Vis spectroscopy. In vitro studies proved that the HAP/PXSA/VK composite is appropriate for mesenchymal stem cell culture. Compared to pure HAP prepared following the same method, HAP/PXSA/VK composite provided favourable microstructures and good biodegradation distinctiveness for the application of tissue engineering, as well as tissue in-growth characteristics and improved scaffold cell penetration. This work reveals that the HAP/PXSA/VK composites have the potential for applications in bone tissue engineering.

Matched MeSH terms: Mesenchymal Stromal Cells
Microbial contamination level of water supply system at the faculty of dentistry, USIM, Malaysia

Normaliza Ab. Malik, Rohazila Mohd Hanafiah, Wan Mohamad Nasi Wan Othman

Sains Malaysiana, 2013;42:53-58.

This study was to evaluate the microbial contamination level in direct water supply at the Polyclinic, Faculty of Dentistry, USIM, Malaysia. Water samples were collected randomly from water supplied via the cup filler outlet of 20 dental units and 20 side water taps at Level 16 and 17 of Polyclinic, Faculty of Dentistry, USIM. All the samples were placed and spread evenly on the surface of prepared agar media (the nutrient agar) using the spread technique. Each sample consists of 0.5 mL water. The microbial count was done using a magnifying glass and the total number of bacteria concentration was reported as colony forming unit in 1 mL of water (cfu/mL). In this study water from an aquarium was used as positive control with 220 cfu/mL, while the distilled water taken from the CSSD was used as negative control with no colony of microorganism. The study demonstrated that there were low contamination before the treatment that was beginning of the session in water supplied via the cup filler outlet and side water tap from the sink with 2 cfu/mL. However, two cup fillers water and one side water taps from Polyclinic level 17 showed a slightly higher bacterial colonies with 4 cfu/mL and 6 cfu/mL of microbes. At the end of the session, result showed that higher bacterial count from Polyclinic level 17 than Polyclinic level 16 with the highest reading of 40 cfu/mL. The findings were considered low and the water was safe for the dental procedures. The quality of water supplied at the Faculty of Dentistry, USIM was within the limits recommended by the American Dental Association, i.e. bacterial loads of not more than 200 cfu/mL for dental procedures.

Matched MeSH terms: Stem Cells
Discovery of gamma-mangostin from Garcinia mangostana as a potent and selective natural SIRT2 inhibitor

Yeong KY, Khaw KY, Takahashi Y, Itoh Y, Murugaiyah V, Suzuki T

Bioorg Chem, 2020 01;94:103403.
PMID: 31711765 DOI: 10.1016/j.bioorg.2019.103403

Studies have suggested that sirtuin inhibition may have beneficial effects on several age-related diseases such as neurodegenerative disorders and cancer. Garcinia mangostana is a well-known tropical plant found mostly in South East Asia with several positive health effects. Some of its phytochemicals such as α-mangostin was found to be able to modulate sirtuin activity in mice and was implicated with inflammation, diabetes and obesity. However, comprehensive studies on sirtuin activity by the prenylated xanthones extracted from Garcinia mangostana have yet to be reported. The present study led to the discovery and identification of γ-mangostin as a potent and selective SIRT2 inhibitor. It was demonstrated that γ-mangostin was able to increase the α-tubulin acetylation in MDA-MD-231 and MCF-7 breast cancer cells. It was also found to possess potent antiproliferative activity against both cell lines. In addition, it was able to induce neurite outgrowth in the N2a cells.

Matched MeSH terms: MCF-7 Cells
Fulltext In Situ Controlled Surface Microstructure of 3D Printed Ti Alloy to Promote Its Osteointegration

Shan L, Kadhum AAH, Al-Furjan MSH, Weng W, Gong Y, Cheng K, et al.

Materials (Basel), 2019 Mar 10;12(5).
PMID: 30857349 DOI: 10.3390/ma12050815

It is well known that three-dimensional (3D) printing is an emerging technology used to produce customized implants and surface characteristics of implants, strongly deciding their osseointegration ability. In this study, Ti alloy microspheres were printed under selected rational printing parameters in order to tailor the surface micro-characteristics of the printed implants during additive manufacturing by an in situ, controlled way. The laser path and hatching space were responsible for the appearance of the stripy structure (S), while the bulbous structure (B) and bulbous⁻stripy composite surface (BS) were determined by contour scanning. A nano-sized structure could be superposed by hydrothermal treatment. The cytocompatibility was evaluated by culturing Mouse calvaria-derived preosteoblastic cells (MC3T3-E1). The results showed that three typical microstructured surfaces, S, B, and BS, could be achieved by varying the 3D printing parameters. Moreover, the osteogenic differentiation potential of the S, B, and BS surfaces could be significantly enhanced, and the addition of nano-sized structures could be further improved. The BS surface with nano-sized structure demonstrated the optimum osteogenic differentiation potential. The present research demonstrated an in situ, controlled way to tailor and optimize the surface structures in micro-size during the 3D printing process for an implant with higher osseointegration ability.

Matched MeSH terms: Cells, Cultured
Fulltext Combinatorial Cytotoxic Effects of Gelam Honey and 5-Fluorouracil against Human Adenocarcinoma Colon Cancer HT-29 Cells In Vitro

T-Johari SAT, Hashim F, Ismail WI, Ali AM

Int J Cell Biol, 2019;2019:3059687.
PMID: 30923553 DOI: 10.1155/2019/3059687

Combination of natural products with chemodrugs is becoming a trend in discovering new therapeutics approach for enhancing the cancer treatment process. In the present study, we aimed to investigate the cytotoxic and apoptosis induction of Gelam honey (GH) combined with or without 5-Fluorouracil (5-FU) on HT-29 cells. The cell viability was determined by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay to assess cytotoxicity. Morphological changes and apoptosis were determined by the inverted microscope, Annexin V-FITC, and DNA fragmentation via flow cytometric analysis, respectively. Our results demonstrate that combined treatment revealed a remarkable and concentration-dependent cytotoxic effect on HT-29 cells in comparison with GH and 5-FU alone. Flow cytometry analysis showed that early apoptosis event was more pronounced in combined treatment. In addition, compared to 5-FU alone, apoptosis of HT-29 cells treated with combinations of GH and 5-FU demonstrated increasing percentages of fragmented DNA. Our results suggest that GH has a synergistic cytotoxic effect with 5-FU in HT-29 cell lines in vitro. Although the actions of the molecular mechanisms are not yet clear, the results reveal that the combination of GH and 5-FU could have the potential as a therapeutic agent.

Matched MeSH terms: HT29 Cells
Fulltext Resistance towards metronidazole in Blastocystis sp.: A pathogenic consequence

Rajamanikam A, Hooi HS, Kudva M, Samudi C, Kumar S

PLoS One, 2019;14(2):e0212542.
PMID: 30794628 DOI: 10.1371/journal.pone.0212542

Blastocsytis sp. is a protozoan parasite that has been linked to common gastrointestinal illnesses. Metronidazole, the first line therapy, was reported to show frequent inefficacy. Previously, Blastocystis sp. isolated from different population showed varying metronidazole resistance. However, the effect of metronidazole treatment on pathogenic potentials of Blastocystis sp. isolated from different populations, which is known to have different gut environment, is unclear. This study investigates the in vitro effect of metronidazole on the pathogenic potentials of Blastocystis sp. isolated from urban and orang asli individuals. Blastocystis sp. ST 3 isolated from symptomatic and asymptomatic individuals were treated with a range of metronidazole concentration. The parasites' growth characteristics, apoptotic rate, specific protease activity and the ability to proliferate cancer cells were analyzed upon treatment with 0.001 mg/l metronidazole. The study demonstrates that Blastocystis sp. isolates showed increase in the parasite numbers especially the amoebic forms (only in urban isolates) after treating with metronidazole at the concentration of 0.001 mg/ml. High number of cells in post-treated isolates coincided with increase of apoptosis. There was a significant increase in cysteine protease of Blastocystis sp. isolates upon treatment despite the initial predominance of serine protease in asymptomatic isolates. Metronidazole resistant Blastocystis sp. also showed significant increase in cancer cell proliferation. Resistance to metronidazole did not show significant different influence on the pathogenicity between Blastocystis sp. isolated from urban and orang asli individual. However, an increase in parasite numbers, higher amoebic forms, cysteine protease and ability to proliferate cancer cells implicates a pathogenic role. The study provides evidence for the first time, the effect of metronidazole towards enhancing pathogenic potentials in Blastocystis sp. when isolated from different gut environment. This necessitates the need for reassessment of metronidazole treatment modalities.

Matched MeSH terms: HCT116 Cells
Fulltext In vitro evaluation of octenidine as an antimicrobial agent against Staphylococcus epidermidis in disinfecting the root canal system

Chum JD, Lim DJZ, Sheriff SO, Pulikkotil SJ, Suresh A, Davamani F

Restor Dent Endod, 2019 Feb;44(1):e8.
PMID: 30834230 DOI: 10.5395/rde.2019.44.e8

Objectives: Irrigants are imperative in endodontic therapy for the elimination of pathogens from the infected root canal. The present study compared the antimicrobial efficacy of octenidine dihydrochloride (OCT) with chlorhexidine (CHX) and sodium hypochlorite (NaOCl) against Staphylococcus epidermidis (S. epidermidis) for root canal disinfection.
Materials and Methods: The minimum inhibitory concentration (MIC) was obtained using serial dilution method. The agar diffusion method was then used to determine the zones of inhibition for each irrigant. Lastly, forty 6-mm dentin blocks were prepared from human mandibular premolars and inoculated with S. epidermidis. Samples were randomly divided into 4 groups of 10 blocks and irrigated for 3 minutes with saline (control), 2% CHX, 3% NaOCl, or 0.1% OCT. Dentin samples were then collected immediately for microbial analysis, including an analysis of colony-forming units (CFUs).
Results: The MICs of each tested irrigant were 0.05% for CHX, 0.25% for NaOCl, and 0.0125% for OCT. All tested irrigants showed concentration-dependent increase in zones of inhibition, and 3% NaOCl showed the largest zone of inhibition amongst all tested irrigants (p < 0.05). There were no significant differences among the CFU measurements of 2% CHX, 3% NaOCl, and 0.1% OCT showing complete elimination of S. epidermidis in all samples.
Conclusions: This study showed that OCT was comparable to or even more effective than CHX and NaOCl, demonstrating antimicrobial activity at low concentrations against S. epidermidis.

Matched MeSH terms: Stem Cells
Isolation methods and culture conditions of human umbilical vein endothelial cells from Malaysian women

Raja Nor Suhaila, Sabreena Safuan

Sains Malaysiana, 2017;46:463-468.

Human umbilical vein endothelial cell (HUVEC) isolated from umbilical cord is widely used as endothelial cell model.
However, HUVEC has been characteristically hard to maintain and showed molecular heterogeneity depending on the
umbilical cord donors. Commercial HUVEC is commonly derived from European and Caucasian population which have
different molecular characteristics from Asian women. This study aimed to optimize the isolation and culture condition of
HUVEC using combinations of growth factors and extracellular matrix components so that the isolated HUVEC will purely
represent the population under study. Umbilical cords were obtained from women post-labour. Different incubation times
and digestive enzymes were used during endothelial cells isolation process. The culture conditions were optimized based
on the coating materials and the media supplements. The results showed that 0.1% collagenase for 40 min incubation
was the optimal isolation condition of HUVEC. HUVEC grown in 0.2% gelatin coated plate with 10% heat-inactivated
fetal calf serum showed higher proliferative capacity and reduced cell death compared to other conditions (p<0.05). The
results generated from this study provide a basic protocol of HUVEC isolation and culture conditions in order to generate
working endothelial cell populations purely represent the Malaysian population.

Matched MeSH terms: Human Umbilical Vein Endothelial Cells

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