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Myofibroblastoma of the breast

Shanmugasiva VV, Ramli Hamid MT, Fadzli F, Shaleen Kaur KS, Abd Rahman N, Rahmat K

Malays J Pathol, 2018 Dec;40(3):349-353.
PMID: 30580368

INTRODUCTION: Myofibroblastoma is a rare benign mesenchymal tumour arising from the stromal elements of the breast tissue. Histopathological variants such as classic, cellular, collagenous / fibrous, lipomatous, infiltrative, myxoid and epithelioid have been identified. Most myofibroblastomas are immunoreactive for CD34, actin, CD10 and desmin, usually express oestrogen receptor (ER), progesterone receptor (PR) and variably express androgen receptor (AR).
CASE REPORT: We report a case of myofibroblastoma in an octogenarian male presenting with painless solitary breast lump. Mammography (digital tomosynthesis) and ultrasound showed a well-circumscribed hyperdense mass and hypoechoic, solid, oval mass with peripheral vascularity respectively. Patient underwent wide local excision.
DISCUSSION: Diverse characteristics of myofibroblastoma on imaging necessitates histopathological analysis for an accurate diagnosis. Myofibroblastoma are often confused with fibroadenomas due to the benign imaging characteristics and with malignant neoplasia due to their wide morphological spectrum. Surgical excision is considered curative.
Fulltext Thymoquinone loaded in nanostructured lipid carrier showed enhanced anticancer activity in 4T1 tumor-bearing mice

Ong YS, Saiful Yazan L, Ng WK, Abdullah R, Mustapha NM, Sapuan S, et al.

Nanomedicine (Lond), 2018 07;13(13):1567-1582.
PMID: 30028248 DOI: 10.2217/nnm-2017-0322

AIM: To investigate the enhancement of anticancer activity of thymoquinone (TQ) by the use of nanostructured lipid carrier (NLC) in 4T1 tumor-bearing female BALB/c mice.
MATERIAL & METHODS: TQ was incorporated into NLC (TQNLC) by using high pressure homogenization. TQNLC and TQ were orally administered to the mice.
RESULTS & CONCLUSION: TQNLC and TQ are potential chemotherapeutic drugs as they exhibited anticancer activity. The use of NLC as a carrier has enhanced the therapeutic property of TQ by increasing the survival rate of mice. The antimetastasis effect of TQNLC and TQ to the lungs was evidence by downregulation of MMP-2. TQNLC and TQ induced apoptosis via modulation of Bcl-2 and caspase-8 in the intrinsic apoptotic pathway.
Fulltext Correction: Synthesis and evaluation of nuciferine and roemerine enantiomers as 5-HT2 and α1 receptor antagonists

Heng HL, Chee CF, Chin SP, Ouyang Y, Wang H, Buckle MJC, et al.

Medchemcomm, 2018 03 01;9(3):593-594.
PMID: 30288212 DOI: 10.1039/c8md90012d

[This corrects the article DOI: 10.1039/C7MD00629B.].
Fulltext Synthesis and evaluation of nuciferine and roemerine enantiomers as 5-HT2 and α1 receptor antagonists

Heng HL, Chee CF, Chin SP, Ouyang Y, Wang H, Buckle MJC, et al.

Medchemcomm, 2018 Mar 01;9(3):576-582.
PMID: 30108948 DOI: 10.1039/c7md00629b

In this study, the (S)-enantiomers of the aporphine alkaloids, nuciferine and roemerine, were prepared via a synthetic route involving catalytic asymmetric hydrogenation and both stereoisomers were evaluated in vitro for functional activity at human 5-HT2 and adrenergic α1 receptor subtypes using a transforming growth factor-α shedding assay. Both enantiomers of each of the compounds were found to act as antagonists at 5-HT2 and α1 receptors. (R)-roemerine was the most potent compound at 5-HT2A and 5-HT2C receptors (pKb = 7.8-7.9) with good selectivity compared to (S)-roemerine at these two receptors and compared to its activity at 5-HT2B, α1A, α1B and α1D receptors.
Fulltext Suppression of Staphylococcus aureus biofilm formation and virulence by a benzimidazole derivative, UM-C162

Kong C, Chee CF, Richter K, Thomas N, Abd Rahman N, Nathan S

Sci Rep, 2018 02 09;8(1):2758.
PMID: 29426873 DOI: 10.1038/s41598-018-21141-2

Staphylococcus aureus is a major cause of nosocomial infections and secretes a diverse spectrum of virulence determinants as well as forms biofilm. The emergence of antibiotic-resistant S. aureus highlights the need for alternative forms of therapeutics other than conventional antibiotics. One route to meet this need is screening small molecule derivatives for potential anti-infective activity. Using a previously optimized C. elegans - S. aureus small molecule screen, we identified a benzimidazole derivative, UM-C162, which rescued nematodes from a S. aureus infection. UM-C162 prevented the formation of biofilm in a dose-dependent manner without interfering with bacterial viability. To examine the effect of UM-C162 on the expression of S. aureus virulence genes, a genome-wide transcriptome analysis was performed on UM-C162-treated pathogen. Our data indicated that the genes associated with biofilm formation, particularly those involved in bacterial attachment, were suppressed in UM-C162-treated bacteria. Additionally, a set of genes encoding vital S. aureus virulence factors were also down-regulated in the presence of UM-C162. Further biochemical analysis validated that UM-C162-mediated disruption of S. aureus hemolysins, proteases and clumping factors production. Collectively, our findings propose that UM-C162 is a promising compound that can be further developed as an anti-virulence agent to control S. aureus infections.
A retrospective analysis of the relationship between facial injury and mild traumatic brain injury

Abdul Razak N, Nordin R, Abd Rahman N, Ramli R

Dent Traumatol, 2017 Oct;33(5):400-405.
PMID: 28649703 DOI: 10.1111/edt.12355

BACKGROUND/AIMS: The association between facial injury characteristics and mild traumatic brain injury (mTBI) is unclear. The aim of this study was to determine the association between facial injury characteristics and mTBI.
METHODS: A retrospective review utilizing patients' medical records at the Universiti Kebangsaan Malaysia Medical Centre (UKMMC), Kuala Lumpur, Malaysia, was performed. Records of subjects with a history of facial trauma from 1 April 2012 to 31 December 2012 were selected. Various levels and surgical speciality records were reviewed to ascertain the diagnoses of facial injuries and mTBI.
RESULTS: A total of 348 medical records with the diagnosis of facial injuries were included. The prevalence of mTBI among these patients was 41.4% (95% CI 36.2-46.6). The majority of the patients with mTBI were in the age group of 18-25 years old. Patients with or without facial lacerations that were located on the lower face had a significant association with mTBI, P=.001, compared to other types of soft tissue injury. In addition, a statistically significant association was observed between facial fractures occurring to the middle face and mTBI, P=.018. Pearson chi-square test also showed statistically significant association between the severity of facial injuries and mTBI, P=.018.
CONCLUSIONS: Mild traumatic brain injury should be suspected in patients with facial injuries and particularly those with lower face lacerations, midface fractures, moderate to severe facial injury and presence of multiple injuries.
Fulltext Dielectrophoresis for Biomedical Sciences Applications: A Review

Abd Rahman N, Ibrahim F, Yafouz B

Sensors (Basel), 2017 Feb 24;17(3).
PMID: 28245552 DOI: 10.3390/s17030449

Dielectrophoresis (DEP) is a label-free, accurate, fast, low-cost diagnostic technique that uses the principles of polarization and the motion of bioparticles in applied electric fields. This technique has been proven to be beneficial in various fields, including environmental research, polymer research, biosensors, microfluidics, medicine and diagnostics. Biomedical science research is one of the major research areas that could potentially benefit from DEP technology for diverse applications. Nevertheless, many medical science research investigations have yet to benefit from the possibilities offered by DEP. This paper critically reviews the fundamentals, recent progress, current challenges, future directions and potential applications of research investigations in the medical sciences utilizing DEP technique. This review will also act as a guide and reference for medical researchers and scientists to explore and utilize the DEP technique in their research fields.
Fulltext Halocarbon emissions by selected tropical seaweeds: species-specific and compound-specific responses under changing pH

Mithoo-Singh PK, Keng FS, Phang SM, Leedham Elvidge EC, Sturges WT, Malin G, et al.

PeerJ, 2017;5:e2918.
PMID: 28149690 DOI: 10.7717/peerj.2918

Five tropical seaweeds, Kappaphycus alvarezii (Doty) Doty ex P.C. Silva, Padina australis Hauck, Sargassum binderi Sonder ex J. Agardh (syn. S. aquifolium (Turner) C. Agardh), Sargassum siliquosum J. Agardh and Turbinaria conoides (J. Agardh) Kützing, were incubated in seawater of pH 8.0, 7.8 (ambient), 7.6, 7.4 and 7.2, to study the effects of changing seawater pH on halocarbon emissions. Eight halocarbon species known to be emitted by seaweeds were investigated: bromoform (CHBr3), dibro-momethane (CH2Br2), iodomethane (CH3I), diiodomethane (CH2I2), bromoiodomethane (CH2BrI), bromochlorometh-ane (CH2BrCl), bromodichloromethane (CHBrCl2), and dibro-mochloromethane (CHBr2Cl). These very short-lived halocarbon gases are believed to contribute to stratospheric halogen concentrations if released in the tropics. It was observed that the seaweeds emit all eight halocarbons assayed, with the exception of K. alvarezii and S. binderi for CH2I2 and CH3I respectively, which were not measurable at the achievable limit of detection. The effect of pH on halocarbon emission by the seaweeds was shown to be species-specific and compound specific. The highest percentage changes in emissions for the halocarbons of interest were observed at the lower pH levels of 7.2 and 7.4 especially in Padina australis and Sargassum spp., showing that lower seawater pH causes elevated emissions of some halocarbon compounds. In general the seaweed least affected by pH change in terms of types of halocarbon emission, was P. australis. The commercially farmed seaweed K. alvarezii was very sensitive to pH change as shown by the high increases in most of the compounds in all pH levels relative to ambient. In terms of percentage decrease in maximum quantum yield of photosynthesis (Fv∕Fm) prior to and after incubation, there were no significant correlations with the various pH levels tested for all seaweeds. The correlation between percentage decrease in the maximum quantum yield of photosynthesis (Fv∕Fm) and halocarbon emission rates, was significant only for CH2BrCl emission by P. australis (r = 0.47; p ≤ 0.04), implying that photosynthesis may not be closely linked to halocarbon emissions by the seaweeds studied. Bromine was the largest contributor to the total mass of halogen emitted for all the seaweeds at all pH. The highest total amount of bromine emitted by K. alvarezii (an average of 98% of total mass of halogens) and the increase in the total amount of chlorine with decreasing seawater pH fuels concern for the expanding seaweed farming activities in the ASEAN region.
Fulltext Synthesis, Biological Evaluation and Molecular Modelling of 2'-Hydroxychalcones as Acetylcholinesterase Inhibitors

Sukumaran SD, Chee CF, Viswanathan G, Buckle MJ, Othman R, Abd Rahman N, et al.

Molecules, 2016 Jul 22;21(7).
PMID: 27455222 DOI: 10.3390/molecules21070955

A series of 2'-hydroxy- and 2'-hydroxy-4',6'-dimethoxychalcones was synthesised and evaluated as inhibitors of human acetylcholinesterase (AChE). The majority of the compounds were found to show some activity, with the most active compounds having IC50 values of 40-85 µM. Higher activities were generally observed for compounds with methoxy substituents in the A ring and halogen substituents in the B ring. Kinetic studies on the most active compounds showed that they act as mixed-type inhibitors, in agreement with the results of molecular modelling studies, which suggested that they interact with residues in the peripheral anionic site and the gorge region of AChE.
Fulltext A heuristic ranking approach on capacity benefit margin determination using Pareto-based evolutionary programming technique

Othman MM, Abd Rahman N, Musirin I, Fotuhi-Firuzabad M, Rajabi-Ghahnavieh A

ScientificWorldJournal, 2015;2015:731013.
PMID: 25879068 DOI: 10.1155/2015/731013

This paper introduces a novel multiobjective approach for capacity benefit margin (CBM) assessment taking into account tie-line reliability of interconnected systems. CBM is the imperative information utilized as a reference by the load-serving entities (LSE) to estimate a certain margin of transfer capability so that a reliable access to generation through interconnected system could be attained. A new Pareto-based evolutionary programming (EP) technique is used to perform a simultaneous determination of CBM for all areas of the interconnected system. The selection of CBM at the Pareto optimal front is proposed to be performed by referring to a heuristic ranking index that takes into account system loss of load expectation (LOLE) in various conditions. Eventually, the power transfer based available transfer capability (ATC) is determined by considering the firm and nonfirm transfers of CBM. A comprehensive set of numerical studies are conducted on the modified IEEE-RTS79 and the performance of the proposed method is numerically investigated in detail. The main advantage of the proposed technique is in terms of flexibility offered to an independent system operator in selecting an appropriate solution of CBM simultaneously for all areas.
Chalcones with electron-withdrawing and electron-donating substituents: anticancer activity against TRAIL resistant cancer cells, structure-activity relationship analysis and regulation of apoptotic proteins

Mai CW, Yaeghoobi M, Abd-Rahman N, Kang YB, Pichika MR

Eur J Med Chem, 2014 Apr 22;77:378-87.
PMID: 24675137 DOI: 10.1016/j.ejmech.2014.03.002

In the present study, a series of 46 chalcones were synthesised and evaluated for antiproliferative activities against the human TRAIL-resistant breast (MCF-7, MDA-MB-231), cervical (HeLa), ovarian (Caov-3), lung (A549), liver (HepG2), colorectal (HT-29), nasopharyngeal (CNE-1), erythromyeloblastoid (K-562) and T-lymphoblastoid (CEM-SS) cancer cells. The chalcone 38 containing an amino (-NH2) group on ring A was the most potent and selective against cancer cells. The effects of the chalcone 38 on regulation of 43 apoptosis-related markers in HT-29 cells were determined. The results showed that 20 apoptotic markers (Bad, Bax, Bcl-2, Bcl-w, Bid, Bim, CD40, Fas, HSP27, IGF-1, IGFBP-4, IGFBP-5, Livin, p21, Survivin, sTNF-R2, TRAIL-R2, XIAP, caspase-3 and caspase-8) were either up regulated or down regulated.
Fulltext Discovery of potential anti-infectives against Staphylococcus aureus using a Caenorhabditis elegans infection model

Kong C, Yehye WA, Abd Rahman N, Tan MW, Nathan S

BMC Complement Altern Med, 2014;14:4.
PMID: 24393217 DOI: 10.1186/1472-6882-14-4

The limited antibiotic options for effective control of methicillin-resistant Staphylococcus aureus infections has led to calls for new therapeutic approaches to combat this human pathogen. An alternative approach to control MRSA is through the use of anti-infective agents that selectively disrupt virulence-mediated pathways without affecting microbial cell viability or by modulating the host natural immune defenses to combat the pathogen.
Fulltext Fusion of protegrin-1 and plectasin to MAP30 shows significant inhibition activity against dengue virus replication

Rothan HA, Bahrani H, Mohamed Z, Abd Rahman N, Yusof R

PLoS One, 2014;9(4):e94561.
PMID: 24722532 DOI: 10.1371/journal.pone.0094561

Dengue virus (DENV) broadly disseminates in tropical and sub-tropical countries and there are no vaccine or anti-dengue drugs available. DENV outbreaks cause serious economic burden due to infection complications that requires special medical care and hospitalization. This study presents a new strategy for inexpensive production of anti-DENV peptide-fusion protein to prevent and/or treat DENV infection. Antiviral cationic peptides protegrin-1 (PG1) and plectasin (PLSN) were fused with MAP30 protein to produce recombinant antiviral peptide-fusion protein (PG1-MAP30-PLSN) as inclusion bodies in E. coli. High yield production of PG1-MAP30-PLSN protein was achieved by solubilization of inclusion bodies in alkaline buffer followed by the application of appropriate refolding techniques. Antiviral PG1-MAP30-PLSN protein considerably inhibited DENV protease (NS2B-NS3pro) with half-maximal inhibitory concentration (IC50) 0.5±0.1 μM. The real-time proliferation assay (RTCA) and the end-point proliferation assay (MTT assay) showed that the maximal-nontoxic dose of the peptide-fusion protein against Vero cells is approximately 0.67±0.2 μM. The cell-based assays showed considerable inhibition of the peptide-fusion protein against binding and proliferating stages of DENV2 into the target cells. The peptide-fusion protein protected DENV2-challeged mice with 100% of survival at the dose of 50 mg/kg. In conclusion, producing recombinant antiviral peptide-fusion protein by combining short antiviral peptide with a central protein owning similar activity could be useful to minimize the overall cost of short peptide production and take advantage of its synergistic antiviral activities.
Food waste and food processing waste for biohydrogen production: a review

Yasin NH, Mumtaz T, Hassan MA, Abd Rahman N

J Environ Manage, 2013 Nov 30;130:375-85.
PMID: 24121591 DOI: 10.1016/j.jenvman.2013.09.009

Food waste and food processing wastes which are abundant in nature and rich in carbon content can be attractive renewable substrates for sustainable biohydrogen production due to wide economic prospects in industries. Many studies utilizing common food wastes such as dining hall or restaurant waste and wastes generated from food processing industries have shown good percentages of hydrogen in gas composition, production yield and rate. The carbon composition in food waste also plays a crucial role in determining high biohydrogen yield. Physicochemical factors such as pre-treatment to seed culture, pH, temperature (mesophilic/thermophilic) and etc. are also important to ensure the dominance of hydrogen-producing bacteria in dark fermentation. This review demonstrates the potential of food waste and food processing waste for biohydrogen production and provides a brief overview of several physicochemical factors that affect biohydrogen production in dark fermentation. The economic viability of biohydrogen production from food waste is also discussed.
Gender differences in coping skills of parents with hearing-impaired children

Md Daud MK, Noor SS, Yusoff MN, Abd Rahman N, Zakaria MN

B-ENT, 2013;9(4):319-23.
PMID: 24597108

To assess differences between the coping strategies of the mothers and fathers with hearing-impaired children.
The performance of distortion product otoacoustic emissions and automated auditory brainstem response in the same ear of the babies in neonatal unit

Abdul Wahid SN, Md Daud MK, Sidek D, Abd Rahman N, Mansor S, Zakaria MN

Int J Pediatr Otorhinolaryngol, 2012 Sep;76(9):1366-9.
PMID: 22770594 DOI: 10.1016/j.ijporl.2012.06.008

OBJECTIVE: To identify the outcomes of hearing screening using different protocols of both Distortion Product Otoacoustic Emissions (DPOAE) and Automated Auditory Brainstem Response (AABR) tests in the same ear of the babies in a neonatal unit population.
METHODS: A cross-sectional study was carried out on babies who were admitted into a neonatal unit. By using a formula of single proportion and considering 20% drop out, the number of sample required was 114. The subjects were chosen by using a systematic random sampling. The infants selected were subjected to DPOAE followed by AABR tests screening at the same setting before discharge.
RESULTS: There were 73 newborns (61.6% male and 38.4% female) participated in this study with a total of 146 ears screened. Ototoxic medication was the most common risk factor followed by hyperbilirubinaemia and low birth weight. AABR had higher passing rate (82.9%) as compared to DPOAE (77.4%). The highest passing rate was achieved if the protocol of either passed DPOAE or AABR was used (90.4%). The rate was lower when auditory neuropathy spectrum disorder (ANSD) has been considered (82.9%). Hyperbilirubinaemia, prematurity, craniofacial malformation and ototoxic drugs seem to be the high risk factors for auditory neuropathy.
CONCLUSION: AABR has a higher passing rate as compared to DPOAE. However, the use of both instruments in the screening process especially in NICU will be useful to determine the infants with ANSD who may need different approach to management. Therefore, a protocol in which newborns are tested with AABR first and then followed by DPOAE on those who fail the AABR is recommended.
Mutation detection in GJB2 gene among Malays with non-syndromic hearing loss

Zainal SA, Md Daud MK, Abd Rahman N, Zainuddin Z, Alwi Z

Int J Pediatr Otorhinolaryngol, 2012 Aug;76(8):1175-9.
PMID: 22613756 DOI: 10.1016/j.ijporl.2012.04.027

To identify the mutations in the GJB2 gene and to determine its association with non-syndromic hearing loss in Malays.
Fulltext Boesenbergia rotunda: From Ethnomedicine to Drug Discovery

Eng-Chong T, Yean-Kee L, Chin-Fei C, Choon-Han H, Sher-Ming W, Li-Ping CT, et al.

Evid Based Complement Alternat Med, 2012;2012:473637.
PMID: 23243448 DOI: 10.1155/2012/473637

Boesenbergia rotunda is a herb from the Boesenbergia genera under the Zingiberaceae family. B. rotunda is widely found in Asian countries where it is commonly used as a food ingredient and in ethnomedicinal preparations. The popularity of its ethnomedicinal usage has drawn the attention of scientists worldwide to further investigate its medicinal properties. Advancement in drug design and discovery research has led to the development of synthetic drugs from B. rotunda metabolites via bioinformatics and medicinal chemistry studies. Furthermore, with the advent of genomics, transcriptomics, proteomics, and metabolomics, new insights on the biosynthetic pathways of B. rotunda metabolites can be elucidated, enabling researchers to predict the potential bioactive compounds responsible for the medicinal properties of the plant. The vast biological activities exhibited by the compounds obtained from B. rotunda warrant further investigation through studies such as drug discovery, polypharmacology, and drug delivery using nanotechnology.
Fulltext 3-(2-Amino-phenyl-sulfanyl)-1,3-diphenyl-propan-1-one

Yaeghoobi M, Khaledi H, Abdullah Z, Abd Rahman N

Acta Crystallogr Sect E Struct Rep Online, 2011 Jul 1;67(Pt 7):o1693.
PMID: 21837090 DOI: 10.1107/S1600536811022112

In the title compound, C(21)H(19)NOS, the three aromatic rings are not coplanar, the dihedral angles between them being 84.75 (7), 88.01 (8) and 8.36 (16)°. In the crystal, two types of C-H⋯ π inter-actions, one of which is weak, and N-H⋯π inter-actions link the mol-ecules into layers parallel to the ab plane.
Screening of dental staff nurses for noise induced hearing loss

Daud MK, Noh NF, Sidek DS, Abd Rahman N, Abd Rani N, Zakaria MN

B-ENT, 2011;7(4):245-9.
PMID: 22338236

The effect of noise on employees of dental clinics is debatable. The purposes of this study were to determine the intensity and frequency components of dental instruments used by dental staff nurses and the prevalence of noise induced hearing loss.

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