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Fulltext Antioxidative Potential of a Streptomyces sp. MUM292 Isolated from Mangrove Soil

Tan LT, Chan KG, Chan CK, Khan TM, Lee LH, Goh BH

Biomed Res Int, 2018;2018:4823126.
PMID: 29805975 DOI: 10.1155/2018/4823126

Mangrove derived microorganisms constitute a rich bioresource for bioprospecting of bioactive natural products. This study explored the antioxidant potentials of Streptomyces bacteria derived from mangrove soil. Based on 16S rRNA phylogenetic analysis, strain MUM292 was identified as the genus Streptomyces. Strain MUM292 showed the highest 16S rRNA gene sequence similarity of 99.54% with S. griseoruber NBRC12873T. Furthermore, strain MUM292 was also characterized and showed phenotypic characteristics consistent with Streptomyces bacteria. Fermentation and extraction were performed to obtain the MUM292 extract containing the secondary metabolites of strain MUM292. The extract displayed promising antioxidant activities, including DPPH, ABTS, and superoxide radical scavenging and also metal-chelating activities. The process of lipid peroxidation in lipid-rich product was also retarded by MUM292 extract and resulted in reduced MDA production. The potential bioactive constituents of MUM292 extract were investigated using GC-MS and preliminary detection showed the presence of pyrazine, pyrrole, cyclic dipeptides, and phenolic compound in MUM292 extract. This work demonstrates that Streptomyces MUM292 can be a potential antioxidant resource for food and pharmaceutical industries.
Recent Modifications and Validation of QuEChERS-dSPE Coupled to LC-MS and GC-MS Instruments for Determination of Pesticide/Agrochemical Residues in Fruits and Vegetables: Review

Lawal A, Wong RCS, Tan GH, Abdulra'uf LB, Alsharif AMA

J Chromatogr Sci, 2018 Aug 01;56(7):656-669.
PMID: 29688338 DOI: 10.1093/chromsci/bmy032

Fruits and vegetables constitute a major type of food consumed daily apart from whole grains. Unfortunately, the residual deposits of pesticides in these products are becoming a major health concern for human consumption. Consequently, the outcome of the long-term accumulation of pesticide residues has posed many health issues to both humans and animals in the environment. However, the residues have previously been determined using conventionally known techniques, which include liquid-liquid extraction, solid-phase extraction (SPE) and the recently used liquid-phase microextraction techniques. Despite the positive technological effects of these methods, their limitations include; time-consuming, operational difficulty, use of toxic organic solvents, low selective property and expensive extraction setups, with shorter lifespan of instrumental performances. Thus, the potential and maximum use of these methods for pesticides residue determination has resulted in the urgent need for better techniques that will overcome the highlighted drawbacks. Alternatively, attention has been drawn recently towards the use of quick, easy, cheap, effective, rugged and safe technique (QuEChERS) coupled with dispersive solid-phase extraction (dSPE) to overcome the setback challenges experienced by the previous technologies. Conclusively, the reviewed QuEChERS-dSPE techniques and the recent cleanup modifications justifiably prove to be reliable for routine determination and monitoring the concentration levels of pesticide residues using advanced instruments such as high-performance liquid chromatography, liquid chromatography-mass spectrometry and gas chromatography-mass spectrometry.
Subcritical water extraction of low methoxyl pectin from pomelo (Citrus grandis (L.) Osbeck) peels

Liew SQ, Teoh WH, Tan CK, Yusoff R, Ngoh GC

Int J Biol Macromol, 2018 Sep;116:128-135.
PMID: 29738869 DOI: 10.1016/j.ijbiomac.2018.05.013

Low methoxyl (LM) pectin was extracted from pomelo peels using subcritical water in a dynamic mode. The effects of pressure and temperature were analyzed through a face-centred central composite design. Extraction yield and the rate of extraction were found to be predominantly influenced by temperature. Optimization of the subcritical water extraction (SWE) yielded an optimized operating condition of 120°C and 30bar with a predicted pectin yield of 18.8%. The corresponding experimental yield was 19.6%, which is in close agreement with the predicted data. The pectin obtained from the optimized condition was further analyzed for its physicochemical properties. The kinetics of the SWE was also evaluated whereby the one-site kinetic desorption model was found to be in good agreement with experimental data (R2>0.94).
Quantitative Hepatitis B e Antigen: A Better Predictor of Hepatitis B Virus DNA than Quantitative Hepatitis B Surface Antigen

Hudu SA, Niazlin MT, Nordin SA, Saeed MI, Tan SS, Omar H, et al.

Clin. Lab., 2018 Apr 01;64(4):443-449.
PMID: 29739076 DOI: 10.7754/Clin.Lab.2017.170916

BACKGROUND: Hepatitis B surface antigen is usually secreted by infected hepatocytes in the form of subviral particles rather than infectious virions, while the hepatitis B e antigen originates from the core gene and is modified and secreted by hepatocytes into the circulation and functions as a marker of active viral replication. This study aimed to study the relationship between HBV DNA and quantitative hepatitis B surface and e antigen in Malaysian patients.
METHODS: A total of 82 chronic hepatitis B patients were recruited for this study from the Hepatology Department of Selayang Hospital. Quantitative hepatitis surface and e antigen was performed retrospectively on frozen plasma using enzyme linked immunosorbent assay according to the manufacturer's instructions. Hepatitis B viral DNA was extracted from all plasma samples and quantified using real-time PCR.
RESULTS: Quantitative hepatitis B surface and e antigens were found be high in 54.9% and 52.4% of the patients, respectively, while hepatitis B virus DNA level was high in 70.7%. The median of the viral load of HBV was 8,934.89 IU/mL and both hepatitis B surface and e antigens were also found to be high on average for qHBsAg (M = 5.19 IU/mL, SD ± 4. 33) and qHBeAg (M = 4.74IU/mL, SD ± 4.20), with qHBeAg being more strongly correlated to HBV DNA than qHBsAg (r = 0.893; p < 0.01).
CONCLUSIONS: This study revealed HBeAg to be the most appropriate marker that correlates well with HBV DNA, thus not completely novel but confirmative, and related to the Malaysian situation.
Fulltext Incorporation of Levodopa into Biopolymer Coatings Based on Carboxylated Carbon Nanotubes for pH-Dependent Sustained Release Drug Delivery

Tan JM, Saifullah B, Kura AU, Fakurazi S, Hussein MZ

Nanomaterials (Basel), 2018 May 31;8(6).
PMID: 29857532 DOI: 10.3390/nano8060389

Four drug delivery systems were formulated by non-covalent functionalization of carboxylated single walled carbon nanotubes using biocompatible polymers as coating agent (i.e., Tween 20, Tween 80, chitosan or polyethylene glycol) for the delivery of levodopa, a drug used in Parkinson's disease. The chemical interaction between the coating agent and carbon nanotubes-levodopa conjugate was confirmed by Fourier transform infrared (FTIR) and Raman studies. The drug release profiles were revealed to be dependent upon the type of applied coating material and this could be further adjusted to a desired rate to meet different biomedical conditions. In vitro drug release experiments measured using UV-Vis spectrometry demonstrated that the coated conjugates yielded a more prolonged and sustained release pattern compared to the uncoated conjugate. Cytotoxicity of the formulated conjugates was studied by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay using normal mouse embryonic fibroblast 3T3 cell line. Compared to the non-coated conjugate, the MTT data indicated that the coating procedure improved the biocompatibility of all systems by 34⁻41% when the concentration used exceeded 100 μg/mL. In conclusion, the comprehensive results of this study suggest that carbon nanotubes-based drug carrier coated with a suitable biomaterial may possibly be a potential nanoparticle system that could facilitate drug delivery to the brain with tunable physicochemical properties.
Social Participation Determines Quality of Life Among Urban-Dwelling Older Adults With Stroke in a Developing Country

Goh HT, Tan MP, Mazlan M, Abdul-Latif L, Subramaniam P

J Geriatr Phys Ther, 2018 6 1;42(4):E77-E84.
PMID: 29851747 DOI: 10.1519/JPT.0000000000000196

BACKGROUND AND PURPOSE: Poor quality of life (QoL) is a well-recognized consequence after stroke. Quality of life is influenced by a complex interaction between personal and environmental factors. Most previous investigations of the QoL after stroke have focused on personal factors, for example, physical deficits directly resulting from stroke. The influence of environmental factors, including social participation, is relatively understudied partly due to its high variation across different sociocultural contexts. The purpose of this study was to investigate the determinants of QoL among older adults with stroke living in an urban area of a developing country.
METHODS: This cross-sectional observational study included 75 older adults who were at least 3 months poststroke and 50 age-matched healthy controls. Depressive symptoms were quantified using the World Health Organization Quality of Life Brief version (WHOQoL-BREF). Physical function was examined using Functional Ambulation Category, grip strength, 5 times Sit-to-Stand test, and Box and Block tests. The Montreal Cognitive Assessment and visual-manual reaction time were used to index cognitive function. Depressive symptom was quantified using the Patient Health Questionnaire-9. The Barthel Index and Fatigue Severity Scale were used to quantify activity limitation. Social participation and environmental participation were assessed using the Assessment of Life Habit and Craig Hospital Inventory of Environment Factors, respectively. Linear stepwise regression models were used to determine explanators for WHOQoL-BREF domain scores.
RESULTS: Individuals with stroke demonstrated significantly worse QoL on all WHOQoL-BREF domains compared with healthy controls. Stroke was a strong determinant for QoL and explained 16% to 43% of variances. Adding other outcome measures significantly improved the robustness of the models (R change = 12%-32%). The physical, psychological, social, and environmental domains of WHOQoL-BREF were all explained by the LIFE-H scores (β = -10.58, -3.37, 4.24, -5.35, respectively), while psychological, social, and environmental domains were explained by Montreal Cognitive Assessment scores (β = .47, 0.78, 0.54, respectively).
CONCLUSION: Social participation and cognition were strong determinants of QoL among urban-dwelling older adults with stroke. Social and recreational activities and cognitive rehabilitation should therefore be evaluated as potential strategies to improve the well-being of older adults affected by stroke.
Fulltext The effect of using games in teaching conservation

Tan CKW, Lee JW, Hii A, Loo YY, Campos-Arceiz A, Macdonald DW

PeerJ, 2018;6:e4509.
PMID: 29736327 DOI: 10.7717/peerj.4509

Games are an increasingly popular approach for conservation teaching. However, we know little about the effectiveness of the games on students' experiences and knowledge acquisition. Many current games are supplemental games (SG) that have no meaningful interaction with the subject matter. We adapted the experiential gaming (EG) model where students were immersed in goal-orientated tasks found in real-life situations, and they tackled questions to complete actions for their main task. Classroom-based games were created for eight different conservation topics for an annual Wildlife Conservation Course and an annual Diploma in International Wildlife Conservation Practice. Data were collected over two cycles, a total sample size of 55 multinational students. We used a combination of repeated-measures design and counterbalanced measures design; each student was subjected at least twice to each of the EG and didactic instruction (DI) treatments, and at least once to the SG approach. We compared students' perception, learning and behavioural responses to the treatments, including measures of student personality types and learning styles as explanatory variables. Findings revealed multiple benefits of the classroom EG compared to the DI approach, such as increased attention retention, increased engagement and added intrinsic motivation. The improved level of intrinsic motivation was mainly facilitated by increased social bonding between participants. Further, we show that this EG approach appeals to a wide range of learning styles and personalities. The performance of SG was generally intermediate between that of EG and DI. We propose EG as a beneficial complement to traditional classroom teaching and current gamified classes for conservation education.
Fulltext A phase I single-blind clinical trial to evaluate the safety of oil palm phenolics (OPP) supplementation in healthy volunteers

Fairus S, Leow SS, Mohamed IN, Tan YA, Sundram K, Sambanthamurthi R

Sci Rep, 2018 05 29;8(1):8217.
PMID: 29844318 DOI: 10.1038/s41598-018-26384-7

Plant phenolics are being increasingly consumed globally with limited scientific and clinical evidence pertaining to safety and efficacy. The oil palm fruit contains a cocktail of phenolics, and palm oil production results in high volumes of aqueous by-products enriched in phenolics and bioactives. Several lines of evidence from in vitro and in vivo animal studies confirmed that the aqueous extract enriched in phenolics and other bioactives collectively known as oil palm phenolics (OPP) is safe and has potent bioactivity. A phase one clinical trial was conducted to evaluate the safety and effects of OPP in healthy volunteers. In this single-blind trial, 25 healthy human volunteers were supplemented with 450 mg gallic acid equivalent (GAE)/day of OPP or control treatments for a 60-day period. Fasting blood and urine samples were collected at days 1, 30 and 60. Medical examination was performed during these trial interventions. All clinical biochemistry profiles observed throughout the control and OPP treatment period were in the normal range with no major adverse effect (AE) or serious adverse effect (SAE) observed. Additionally, OPP supplementation resulted in improvement of total cholesterol and LDL-C levels, compared to the control treatment. The outcomes support our previous observations that OPP is safe and may have a protective role in reducing cholesterol levels.
Fulltext Targeted Delivery of Cell Penetrating Peptide Virus-like Nanoparticles to Skin Cancer Cells

Gan BK, Yong CY, Ho KL, Omar AR, Alitheen NB, Tan WS

Sci Rep, 2018 05 31;8(1):8499.
PMID: 29855618 DOI: 10.1038/s41598-018-26749-y

Skin cancer or cutaneous carcinoma, is a pre-eminent global public health problem with no signs of plateauing in its incidence. As the most common treatments for skin cancer, surgical resection inevitably damages a patient's appearance, and chemotherapy has many side effects. Thus, the main aim of this study was to screen for a cell penetrating peptide (CPP) for the development of a targeting vector for skin cancer. In this study, we identified a CPP with the sequence NRPDSAQFWLHH from a phage displayed peptide library. This CPP targeted the human squamous carcinoma A431 cells through an interaction with the epidermal growth factor receptor (EGFr). Methyl-β-cyclodextrin (MβCD) and chlorpromazine hydrochloride (CPZ) inhibited the internalisation of the CPP into the A431 cells, suggesting the peptide entered the cells via clathrin-dependent endocytosis. The CPP displayed on hepatitis B virus-like nanoparticles (VLNPs) via the nanoglue successfully delivered the nanoparticles into A431 cells. The present study demonstrated that the novel CPP can serve as a ligand to target and deliver VLNPs into skin cancer cells.
Fulltext The crucial role of molecular testing to facilitate the diagnosis of pneumocystis pneumonia during pregnancy

Ding CH, Yusoff H, Muttaqillah NAS, Tang YL, Tan TL, Periyasamy P, et al.

Malays J Pathol, 2018 Apr;40(1):69-72.
PMID: 29704387 MyJurnal

Pneumocystis pneumonia is an important human immunodeficiency virus (HIV)-associated opportunistic infection, and especially so in pregnant HIV-positive patients. We report a case of a 40-year-old woman in her first trimester of pregnancy who initially presented with acute gastroenteritis symptoms but due to a history of high-risk behaviour and the observation of oral thrush, she was worked up for HIV infection. Her retroviral status was positive and her CD4+ T cell count was only 8 cells/µL. She was also worked up for pneumocystis pneumonia due to the presence of mild resting tachypnoea and a notable drop in oxygen saturation (from 100% to 88%) following brief ambulation. Her chest radiograph revealed bilaterally symmetrical lower zone reticular opacities and Giemsa staining of her bronchoalveolar lavage (BAL) was negative for Pneumocystis jirovecii cysts. However, real-time P. jirovecii polymerase chain reaction (PCR) testing on the same BAL specimen revealed the presence of the organism. A course of oral co-trimoxazole plus prednisolone was commenced and her clinical condition improved.
The spectrum of pathological findings of tonsils in children: A clinicopathological review

Tan GC, Stalling M, Al-Rawabdeh S, Kahwash BM, Alkhoury RF, Kahwash SB

Malays J Pathol, 2018 Apr;40(1):11-26.
PMID: 29704380

Tonsillectomy is among the most commonly performed operations in children. Although follicular lymphoid hyperplasia is usually the main and only pathologic finding at microscopic examination, a variety of other rare but important pathologic changes may be encountered. This review aims to provide an inclusive practical resource and reference for both training and practising pathologists. It discusses the spectrum of pathologic findings, including both neoplastic and non-neoplastic conditions and provides illustrative images.
Direct recovery of mangostins from Garcinia mangostana pericarps using cellulase-assisted aqueous micellar biphasic system with recyclable surfactant

Ng HS, Tan GYT, Lee KH, Zimmermann W, Yim HS, Lan JC

J Biosci Bioeng, 2018 Oct;126(4):507-513.
PMID: 29764763 DOI: 10.1016/j.jbiosc.2018.04.008

The α- and γ-mangostins from Garcinia mangostana pericarps (GMP) exhibit antioxidant, anti-bacterial, anti-inflammatory and anti-tumor properties. The extraction yields α- and γ-mangostins are often limited by the presence of the GMP cell walls. Therefore, the extraction and recovery of mangostins from GMP with an Aspergillus niger cellulase-assisted aqueous micellar biphasic system (CA-AMBS) was developed for enhanced yield of mangostins. Effects of the concentration of cellulase, the incubation time and the temperature of the system on the recovery of mangostins were investigated. The optimum condition for the recovery of α- and γ-mangostins was obtained with the addition of 0.5% (w/w) cellulase incubated at 40°C for 2 h. High log partition coefficients of α-mangostins (log Kα 4.79 ± 0.02) and γ-mangostins (log Kγ 4.02 ± 0.02) were achieved. High yields of α-mangostins (73.4%) and γ-mangostins (14.0%) were obtained from the micelle-rich bottom phase with final concentrations of 3.67 mg/mL and 0.70 mg/mL, respectively. The back-extraction of mangostins was performed with the addition of 30% (w/w) of isopropanol and 0.05 M of KCl at pH 9 to the bottom phase of the CA-AMBS. The yields of the α- and γ-mangostins from GMP were considerably enhanced with the CA-AMBS and the direct recovery of mangostins was demonstrated without additional downstream processing steps.
Fulltext Estimating renal function in the elderly Malaysian patients attending medical outpatient clinic: a comparison between creatinine-based and cystatin-C based equations

Jalalonmuhali M, Elagel SMA, Tan MP, Lim SK, Ng KP

Int J Nephrol, 2018;2018:3081518.
PMID: 29862077 DOI: 10.1155/2018/3081518

Background: To assess the performance of different GFR estimating equations, test the diagnostic value of serum cystatin-C, and compare the applicability of cystatin-C based equation with serum creatinine based equation for estimating GFR (eGFR) in comparison with measured GFR in the elderly Malaysian patients.

Methods: A cross-sectional study recruiting volunteered patients 65 years and older attending medical outpatient clinic. 51 chromium EDTA (51Cr-EDTA) was used as measured GFR. The predictive capabilities of Cockcroft-Gault equation corrected for body surface area (CGBSA), four-variable Modification of Diet in Renal Disease (4-MDRD), and Chronic Kidney Disease Epidemiology Collaboration (CKD-EPI) equations using serum creatinine (CKD-EPIcr) as well as serum cystatin-C (CKD-EPIcys) were calculated.

Results: A total of 40 patients, 77.5% male, with mean measured GFR 41.2 ± 18.9 ml/min/1.73 m2 were enrolled. Mean bias was the smallest for 4-MDRD; meanwhile, CKD-EPIcr had the highest precision and accuracy with lower limit of agreement among other equations. CKD-EPIcys equation did not show any improvement in GFR estimation in comparison to CKD-EPIcr and MDRD.

Conclusion: The CKD-EPIcr formula appears to be more accurate and correlates better with measured GFR in this cohort of elderly patients.

Study site: medical outpatient clinic. University of Malaya Medical Centre (UMMC)
Fulltext Type 2 diabetes patient's perspective on Ramadan fasting: a qualitative study

Lee JY, Wong CP, Tan CSS, Nasir NH, Lee SWH

BMJ Open Diabetes Res Care, 2017;5(1):e000365.
PMID: 28761651 DOI: 10.1136/bmjdrc-2016-000365

OBJECTIVE: We evaluated the beliefs, experience and diabetes management strategies of type 2 diabetes mellitus (T2DM) Muslim patients that chose to fast during Ramadan.
RESEARCH DESIGN AND METHODS: A semistructured focus group interview was conducted with 53 participants with T2DM. Participants were purposefully sampled and asked to share their perspective on Ramadan fasting. All interviews were audio recorded, transcribed verbatim and analyzed thematically.
RESULTS: Participants reported optimism towards fasting during Ramadan, as they believed that fasting was beneficial to their overall well-being, and a time for family bonding. Most participants made limited attempts to discuss with their doctors on the decision to fast and self-adjusted their medication based on experience and symptoms during this period. They also reported difficulty in managing their diet, due to fear of hypoglycemia and the collective social aspect of fasting.
CONCLUSION: Muslims are optimistic about their well-being when fasting during Ramadan. Many choose to fulfill their religious obligation despite being discouraged by their doctors. Collaboration with religious authorities should be explored to ensure patients receive adequate education before fasting during Ramadan.
TRIAL REGISTRATION NUMBER: NCT02189135; Results.
Fulltext Piper betle L. Modulates Senescence-Associated Genes Expression in Replicative Senescent Human Diploid Fibroblasts

Durani LW, Khor SC, Tan JK, Chua KH, Mohd Yusof YA, Makpol S

Biomed Res Int, 2017;2017:6894026.
PMID: 28596968 DOI: 10.1155/2017/6894026

Piper betle
(PB) is a traditional medicine that is widely used to treat different diseases around Asian region. The leaf extracts contain various bioactive compounds, which were reported to have antidiabetic, antibacterial, anti-inflammatory, antioxidant, and anticancer effects. In this study, the effect of PB aqueous extracts on replicative senescent human diploid fibroblasts (HDFs) was investigated by determining the expressions of senescence-associated genes using quantitative PCR. Our results showed that PB extracts at 0.4 mg/ml can improve cell proliferation of young (143%), presenescent (127.3%), and senescent (157.3%) HDFs. Increased expressions ofPRDX6,TP53,CDKN2A,PAK2, andMAPK14were observed in senescent HDFs compared to young and/or presenescent HDFs. Treatment with PB extracts modulates the transcriptional profile changes in senescent HDFs. By contrast, expressions ofSOD1increased, whereasGPX1,PRDX6,TP53,CDKN2A,PAK2, andMAPK14were decreased in PB-treated senescent HDFs compared to untreated senescent HDFs. In conclusion, this study indicates the modulation of PB extracts on senescence-associated genes expression of replicative senescent HDFs. Further studies warrant determining the mechanism of PB in modulating replicative senescence of HDFs through these signaling pathways.
Fulltext Distinct Biological Potential of Streptococcus gordonii and Streptococcus sanguinis Revealed by Comparative Genome Analysis

Zheng W, Tan MF, Old LA, Paterson IC, Jakubovics NS, Choo SW

Sci Rep, 2017 06 07;7(1):2949.
PMID: 28592797 DOI: 10.1038/s41598-017-02399-4

Streptococcus gordonii and Streptococcus sanguinis are pioneer colonizers of dental plaque and important agents of bacterial infective endocarditis (IE). To gain a greater understanding of these two closely related species, we performed comparative analyses on 14 new S. gordonii and 5 S. sanguinis strains using various bioinformatics approaches. We revealed S. gordonii and S. sanguinis harbor open pan-genomes and share generally high sequence homology and number of core genes including virulence genes. However, we observed subtle differences in genomic islands and prophages between the species. Comparative pathogenomics analysis identified S. sanguinis strains have genes encoding IgA proteases, mitogenic factor deoxyribonucleases, nickel/cobalt uptake and cobalamin biosynthesis. On the contrary, genomic islands of S. gordonii strains contain additional copies of comCDE quorum-sensing system components involved in genetic competence. Two distinct polysaccharide locus architectures were identified, one of which was exclusively present in S. gordonii strains. The first evidence of genes encoding the CylA and CylB system by the α-haemolytic S. gordonii is presented. This study provides new insights into the genetic distinctions between S. gordonii and S. sanguinis, which yields understanding of tooth surfaces colonization and contributions to dental plaque formation, as well as their potential roles in the pathogenesis of IE.
Fulltext Anti-neuroinflammatory Activity of Elephantopus scaber L. via Activation of Nrf2/HO-1 Signaling and Inhibition of p38 MAPK Pathway in LPS-Induced Microglia BV-2 Cells

Chan CK, Tan LT, Andy SN, Kamarudin MNA, Goh BH, Kadir HA

Front Pharmacol, 2017;8:397.
PMID: 28680404 DOI: 10.3389/fphar.2017.00397

Elephantopus scaber L. (family: Asteraceae) has been traditionally utilized as a folkloric medicine and scientifically shown to exhibit anti-inflammatory activities in various in vivo inflammatory models. Given the lack of study on the effect of E. scaber in neuroinflammation, this study aimed to investigate the anti-neuroinflammatory effect and the underlying mechanisms of ethyl acetate fraction from the leaves of E. scaber (ESEAF) on the release of pro-inflammatory mediators in lipopolysaccharide (LPS)-induced microglia cells (BV-2). Present findings showed that ESEAF markedly attenuated the translocation of NF-κB to nucleus concomitantly with the significant mitigation on the LPS-induced production of NO, iNOS, COX-2, PGE2, IL-1β, and TNF-α. These inflammatory responses were reduced via the inhibition of p38. Besides, ESEAF was shown to possess antioxidant activities evident by the DPPH and SOD scavenging activities. The intracellular catalase enzyme activity was enhanced by ESEAF in the LPS-stimulated BV-2 cells. Furthermore, the formation of ROS induced by LPS in BV-2 cells was reduced upon the exposure to ESEAF. Intriguingly, the reduction of ROS was found in concerted with the activation of Nrf2 and HO-1. It is conceivable that the activation promotes the scavenging power of antioxidant enzymes as well as to ameliorate the inflammatory response in LPS-stimulated BV-2 cells. Finally, the safety profile analysis through oral administration of ESEAF at 2000 mg/kg did not result in any mortalities, adverse effects nor histopathologic abnormalities of organs in mice. Taken altogether, the cumulative findings suggested that ESEAF holds the potential to develop as nutraceutical for the intervention of neuroinflammatory disorders.
Fulltext Cancer Pain Management Insights and Reality in Southeast Asia: Expert Perspectives From Six Countries

Javier FO, Irawan C, Mansor MB, Sriraj W, Tan KH, Thinh DHQ

J Glob Oncol, 2016 Aug;2(4):235-243.
PMID: 28717706 DOI: 10.1200/JGO.2015.001859

This expert opinion report examines the current realities of the cancer pain management landscape and the various factors that hinder optimal pain control in six countries in Southeast Asia, describes ongoing efforts to advance patient care, and discusses approaches for improving cancer pain management. Information was gathered from leading experts in the field of cancer pain management in each country through an initial meeting and subsequent e-mail discussions. Overall, there are vast disparities in cancer pain management practices and access to opioids in the Southeast Asian countries. The experts considered cancer pain as being generally undermanaged. Access to opioids is inadequate in most countries, and opioid use for analgesia remains inadequate in the region. Several system-, physician-, and patient-related barriers to adequate pain relief were identified, including widespread over-regulation of opioid use, shortage of trained health care workers, inadequacies in pain assessment and knowledge about managing pain, and widespread resistance among patients and physicians toward opioid treatment. According to the experts, many of the ongoing initiatives in the Southeast Asian countries are related to educating patients and physicians on cancer pain management and opioid use. Efforts to improve opioid availability and reduce regulatory barriers in the region are limited, and much work is still needed to improve the status of cancer pain management in the region. Enacting necessary change will require recognition of the unique needs and resources of each country and collaboration across interdisciplinary professional teams to improve cancer pain care in this region.
Pseudo-nitzschia simulans sp. nov. (Bacillariophyceae), the first domoic acid producer from Chinese waters

Li Y, Huang CX, Xu GS, Lundholm N, Teng ST, Wu H, et al.

Harmful Algae, 2017 07;67:119-130.
PMID: 28755714 DOI: 10.1016/j.hal.2017.06.008

The genus Pseudo-nitzschia has attracted attention because of production of the toxin, domoic acid (DA), causing Amnesic Shellfish Poisoning (ASP). Pseudo-nitzschia blooms occur frequently in Chinese coastal waters, and DA has been detected in several marine organisms, but so far no Pseudo-nitzschia strains from Chinese waters have been shown to produce DA. In this study, monoclonal Pseudo-nitzschia strains were established from Chinese coastal waters and examined using light microscopy, electron microscopy and molecular markers. Five strains, sharing distinct morphological and molecular features differentiating them from other Pseudo-nitzschia species, represent a new species, Pseudo-nitzschia simulans sp. nov. Morphologically, the taxon belongs to the P. pseudodelicatissima group, cells possessing a central nodule and each stria comprising one row of poroids. The new species is characterized by the poroid structure, which typically comprises two sectors, each sector located near opposite margins of the poroid. The production of DA was examined by liquid chromatography tandem mass spectrometry (LC-MS/MS) analyses of cells in stationary growth phase. Domoic acid was detected in one of the five strains, with concentrations around 1.05-1.54 fg cell-1. This is the first toxigenic diatom species reported from Chinese waters.
Biophysical characterization of layer-by-layer synthesis of aptamer-drug microparticles for enhanced cell targeting

Tan KX, Danquah MK, Sidhu A, Lau SY, Ongkudon CM

Biotechnol Prog, 2018 01;34(1):249-261.
PMID: 28699244 DOI: 10.1002/btpr.2524

Targeted delivery of drug molecules to specific cells in mammalian systems demonstrates a great potential to enhance the efficacy of current pharmaceutical therapies. Conventional strategies for pharmaceutical delivery are often associated with poor therapeutic indices and high systemic cytotoxicity, and this result in poor disease suppression, low surviving rates, and potential contraindication of drug formulation. The emergence of aptamers has elicited new research interests into enhanced targeted drug delivery due to their unique characteristics as targeting elements. Aptamers can be engineered to bind to their cognate cellular targets with high affinity and specificity, and this is important to navigate active drug molecules and deliver sufficient dosage to targeted malignant cells. However, the targeting performance of aptamers can be impacted by several factors including endonuclease-mediated degradation, rapid renal filtration, biochemical complexation, and cell membrane electrostatic repulsion. This has subsequently led to the development of smart aptamer-immobilized biopolymer systems as delivery vehicles for controlled and sustained drug release to specific cells at effective therapeutic dosage and minimal systemic cytotoxicity. This article reports the synthesis and in vitro characterization of a novel multi-layer co-polymeric targeted drug delivery system based on drug-loaded PLGA-Aptamer-PEI (DPAP) formulation with a stage-wise delivery mechanism. A thrombin-specific DNA aptamer was used to develop the DPAP system while Bovine Serum Albumin (BSA) was used as a biopharmaceutical drug in the synthesis process by ultrasonication. Biophysical characterization of the DPAP system showed a spherical shaped particulate formulation with a unimodal particle size distribution of average size ∼0.685 µm and a zeta potential of +0.82 mV. The DPAP formulation showed a high encapsulation efficiency of 89.4 ± 3.6%, a loading capacity of 17.89 ± 0.72 mg BSA protein/100 mg PLGA polymeric particles, low cytotoxicity and a controlled drug release characteristics in 43 days. The results demonstrate a great promise in the development of DPAP formulation for enhanced in vivo cell targeting. © 2017 American Institute of Chemical Engineers Biotechnol. Prog., 34:249-261, 2018.

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