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Fulltext Subperiosteal Drainage versus Subdural Drainage in the management of Chronic Subdural Hematoma (A Comparative Study)

Chih AN, Hieng AW, Rahman NA, Abdullah JM

Malays J Med Sci, 2017 Mar;24(1):21-30.
PMID: 28381926 DOI: 10.21315/mjms2017.24.1.3

INTRODUCTION: Symptomatic chronic subdural hematomas (CSDH) remain one of the most frequent diagnoses in current neurosurgical practice. Burr-hole craniostomy with irrigation and placement of close-system drainage is the current recommended surgery for symptomatic CSDH. The aim of this study is to perform a direct comparison between two surgical techniques in the treatment of symptomatic CSDH, which have been proven in previous studies to be efficient. Our main objective was to compare the efficacy of placement of a subperiosteal drain (SPD) and a subdural drain (SDD) following single burr-hole craniostomy and irrigation, and to demonstrate any significant differences in terms of overall surgical complications, functional outcome at three months and mortality rate.
MATERIALS AND METHODS: The study was carried out in two local neurosurgical centres. The SPD group was performed in Hospital Umum Sarawak (HUS) and the SDD group was performed in Hospital Sultanah Aminah Johor Bahru (HSAJB), from 1 January 2012 till 30 January 2014 with a total of 30 patients in both treatment groups.
RESULTS: Overall, there were no statistically significant difference in terms of patient general characteristics, pre-operative and post-operative symptoms, Markwalder grades, post-operative hematoma volume and recurrence, mortality and functional outcome at discharge and at three month follow-up between both groups. Albeit not achieving statistical significance, we observed a lower rate of surgical complication especially for post-operative intracranial hematoma with placement of the SPD system.
CONCLUSIONS: Our study concludes that both treatment methods proved to be highly effective in the treatment of CSDH. However, with a lower overall surgical complication rate, treatment with single burr-hole craniostomy, irrigation and placement of the SPD system can be considered a treatment of choice for the management of symptomatic CSDH.
The Curious Incidence of Mucinous Adenocarcinoma Masquerading as Perianal Hidradenitis Suppurativa

Nasir H, Mohammad Azmi N, Dualim DM, Azman ZA, Abdul Rahman NA

Cureus, 2024 Apr;16(4):e57585.
PMID: 38707052 DOI: 10.7759/cureus.57585

Hidradenitis suppurativa (HS), also known as acne inversa, is a chronic inflammatory disorder affecting the terminal follicular epithelium within the apocrine skin glands. When these lesions develop in the genital and perianal regions, there is a potential risk of progression to squamous cell carcinoma or mucinous adenocarcinoma. The tumor may appear in the perianal area, perineum, or buttocks. Here, we present a rare case of long-standing perianal HS with associated fistula-related mucinous adenocarcinoma and the challenges we faced in managing this condition.
How plants respond to heavy metal contamination: a narrative review of proteomic studies and phytoremediation applications

Al-Obaidi JR, Jamaludin AA, Rahman NA, Ahmad-Kamil EI

Planta, 2024 Mar 29;259(5):103.
PMID: 38551683 DOI: 10.1007/s00425-024-04378-2

Heavy metal pollution caused by human activities is a serious threat to the environment and human health. Plants have evolved sophisticated defence systems to deal with heavy metal stress, with proteins and enzymes serving as critical intercepting agents for heavy metal toxicity reduction. Proteomics continues to be effective in identifying markers associated with stress response and metabolic processes. This review explores the complex interactions between heavy metal pollution and plant physiology, with an emphasis on proteomic and biotechnological perspectives. Over the last century, accelerated industrialization, agriculture activities, energy production, and urbanization have established a constant need for natural resources, resulting in environmental degradation. The widespread buildup of heavy metals in ecosystems as a result of human activity is especially concerning. Although some heavy metals are required by organisms in trace amounts, high concentrations pose serious risks to the ecosystem and human health. As immobile organisms, plants are directly exposed to heavy metal contamination, prompting the development of robust defence mechanisms. Proteomics has been used to understand how plants react to heavy metal stress. The development of proteomic techniques offers promising opportunities to improve plant tolerance to toxicity from heavy metals. Additionally, there is substantial scope for phytoremediation, a sustainable method that uses plants to extract, sequester, or eliminate contaminants in the context of changes in protein expression and total protein behaviour. Changes in proteins and enzymatic activities have been highlighted to illuminate the complex effects of heavy metal pollution on plant metabolism, and how proteomic research has revealed the plant's ability to mitigate heavy metal toxicity by intercepting vital nutrients, organic substances, and/or microorganisms.
Door-to-Skin Time in Patient Undergoing Emergency Trauma Craniotomy

Chockalingam K, A Rahman NA, Idris Z, Theophilus SC, Abdullah JM, Ghani ARI, et al.

Malays J Med Sci, 2023 Aug;30(4):71-84.
PMID: 37655152 DOI: 10.21315/mjms2023.30.4.7

BACKGROUND: Traumatic brain injury (TBI) is the third leading cause of death and disability worldwide in 2020. For patients with TBI with significant intracranial bleeds, urgent surgical intervention remains the mainstay treatment. This study aims to evaluate the time to definite surgical intervention since admission and its association with patient outcomes in a neurosurgery referral centre in Malaysia.
METHODS: This retrospective study was conducted at Hospital Sultanah Aminah Johor Bahru from 1 January 2019 to 31 December 2019. All patients with TBI requiring urgent craniotomy were identified from the operating theatre registry, and the required data were extracted from their clinical notes, including the Glasgow Outcome Score (GCS) at discharge and 6 months later. Logistic regression was performed to identify the factors associated with poor outcomes.
RESULTS: A total of 154 patients were included in this study. The median door-to-skin time was 605 (interquartile range = 494-766) min. At discharge, 105 patients (68.2%) had poor outcomes. At the 6-month follow-up, only 58 patients (37.7%) remained to have poor outcomes. Simple logistic regression showed that polytrauma, hypotensive episode, ventilation, severe TBI, and the door-to-skin time were significantly associated with poor outcomes. After adjustments for the clinical characteristics in the analysis, the likelihood of having poor outcomes for every minute delay in the door-to-skin time increased at discharge (adjusted odds ratio [AOR] = 1.005; 95% confidence interval [CI] = 1.002-1.008) and the 6-month follow-up (AOR = 1.008; 95% CI = 1.005-1.011).
CONCLUSION: The door-to-skin time is directly proportional to poor outcomes in patients with TBI. Concerted efforts from all parties involved in trauma care are essential in eliminating delays in surgical interventions and improving outcomes.
A study on the magnitude and the effectiveness of the observation ward of hospital universiti sains malaysia

Ahmad R, Nik Abdul Rahman NH, Mohd Noh AY, Nik Abdul Rahman NA, Mohamad N, Baharudin KA

Malays J Med Sci, 2010 Jan;17(1):38-43.
PMID: 22135524 MyJurnal

BACKGROUND: The observation ward (OW) allows patients to be reassessed and monitored before deciding either to admit or to discharge them. This is a six-month descriptive cross-sectional study conducted in the observation ward of the Emergency Department (ED) of Hospital Universiti Sains Malaysia, Kelantan. The objective of this study was to examine the demographic characteristics and clinical profiles of adult observed patients and to determine the effectiveness of OW management.
METHODS: Patients were selected randomly by convenience sampling. One hundred and twenty-four patients were included in the study. The mean age was 40.3 ± 18.5 years (95% CI: 37.2 to 43.8).
RESULTS: Among the common clinical problems were abdominal discomfort (23%), diarrhoea and vomiting (13%) and fever (13%). Reasons for OW admission included diagnostic uncertainty (63%) and short course of treatment (33%). The mean length of stay was 4.1 ± 1.8 hours (95% CI=3.8 to 4.4 hours). Most of the patients (85%) were discharged.
CONCLUSIONS: The OW of HUSM is effective in managing adult patients as determined by the hospitalisation rate and the length of stay.
Inhibitory effect of doxycycline against dengue virus replication in vitro

Rothan HA, Mohamed Z, Paydar M, Rahman NA, Yusof R

Arch Virol, 2014 Apr;159(4):711-8.
PMID: 24142271 DOI: 10.1007/s00705-013-1880-7

Doxycycline is an antibiotic derived from tetracycline that possesses antimicrobial and anti-inflammatory activities. Antiviral activity of doxycycline against dengue virus has been reported previously; however, its anti-dengue properties need further investigation. This study was conducted to determine the potential activity of doxycycline against dengue virus replication in vitro. Doxycycline inhibited the dengue virus serine protease (DENV2 NS2B-NS3pro) with an IC50 value of 52.3 ± 6.2 μM at 37 °C (normal human temperature) and 26.7 ± 5.3 μM at 40 °C (high fever temperature). The antiviral activity of doxycycline was first tested at different concentrations against DENV2 using a plaque-formation assay. The virus titter decreased significantly after applying doxycycline at levels lower than its 50 % cytotoxic concentration (CC50, 100 μM), showing concentration-dependent inhibition with a 50 % effective concentration (EC50) of approximately 50 μM. Doxycycline significantly inhibited viral entry and post-infection replication of the four dengue serotypes, with serotype-specific inhibition (high activity against DENV2 and DENV4 compared to DENV1 and DENV3). Collectively, these findings underline the need for further experimental and clinical studies on doxycycline, utilizing its anti-dengue and anti-inflammatory activities to attenuate the clinical symptoms of dengue virus infection.
Fulltext Design of new competitive dengue NS2B/NS3 protease inhibitors-a computational approach

Frimayanti N, Chee CF, Zain SM, Rahman NA

Int J Mol Sci, 2011;12(2):1089-100.
PMID: 21541045 DOI: 10.3390/ijms12021089

Dengue is a serious disease which has become a global health burden in the last decade. Currently, there are no approved vaccines or antiviral therapies to combat the disease. The increasing spread and severity of the dengue virus infection emphasizes the importance of drug discovery strategies that could efficiently and cost-effectively identify antiviral drug leads for development into potent drugs. To this effect, several computational approaches were applied in this work. Initially molecular docking studies of reference ligands to the DEN2 NS2B/NS3 serine protease were carried out. These reference ligands consist of reported competitive inhibitors extracted from Boesenbergia rotunda (i.e., 4-hydroxypanduratin A and panduratin A) and three other synthesized panduratin A derivative compounds (i.e., 246DA, 2446DA and 20H46DA). The design of new lead inhibitors was carried out in two stages. In the first stage, the enzyme complexed to the reference ligands was minimized and their complexation energies (i.e., sum of interaction energy and binding energy) were computed. New compounds as potential dengue inhibitors were then designed by putting various substituents successively on the benzyl ring A of the reference molecule. These substituted benzyl compounds were then computed for their enzyme-ligand complexation energies. New enzyme-ligand complexes, exhibiting the lowest complexation energies and closest to the computed energy for the reference compounds, were then chosen for the next stage manipulation and design, which involved substituting positions 4 and 5 of the benzyl ring A (positions 3 and 4 for 2446DA) with various substituents.
Synthesis of methyl esters from palm (Elaeis guineensis) oil using cobalt doped MgO as solid oxide catalyst

Rahman NA, Olutoye MA, Hameed BH

Bioresour Technol, 2011 Oct;102(20):9749-54.
PMID: 21855332 DOI: 10.1016/j.biortech.2011.07.023

The potential of Mg(x)Co(2-)(x)O(2) as heterogeneous reusable catalyst in transesterification of palm oil to methyl ester was investigated. The catalyst was prepared via co-precipitation of the metal hydroxides at different Mg-Co ratios. Mg(1.7)Co(0.3)O(2) catalyst was more active than Mg(0.3)Co(1.7)O(2) in the transesterification of palm oil with methanol. The catalysts calcined at temperature 300 °C for 4 h resulted in highly active oxides and the highest transesterification of 90% was achieved at methanol/oil molar ratio of 9:1, catalyst loading of 5.00 wt.%, reaction temperature of 150 °C and reaction time of 2 h. The catalyst could easily be removed from reaction mixture, but showed 50% decrease in activity when reused due to leaching of active sites.
Removal of selected endocrine disrupting chemicals and personal care products in surface waters and secondary wastewater by ozonation

Tay KS, Rahman NA, Abas MR

Water Environ Res, 2011 Aug;83(8):684-91.
PMID: 21905405

This study investigated the removal of parabens, N,N-diethyl-m-toluamide (DEET), and phthalates by ozonation. The second-order rate constants for the reaction between selected compounds with ozone at pH 7 were of (2.2 +/-0.2) X 10(6) to (2.9 +/-0.3) X 10(6) M 1/s for parabens, (2.1+/- 0.3) to (3.9 +/-0.5) M-1/s for phthalates, and (5.2 +/-0.3) M-1/s for DEET. The rate constants for the reaction between selected compounds with hydroxyl radical ranged from (2.49 +/-0.06) x 10(9) to (8.5 +/-0.2) x 10(9) M-1/s. Ozonation of selected compounds in secondary wastewater and surface waters revealed that ozone dose of 1 and 3 mg/L yielded greater than 99% depletion of parabens and greater than 92% DEET and phthalates, respectively. In addition, parabens were found to transform almost exclusively through the reaction with ozone, while DEET and phthalates were transformed almost entirely by hydroxyl radicals (.OH).
Enantioselective organocatalytic Diels-Alder reactions: a density functional theory and kinetic isotope effects study

Omar NY, Rahman NA, Zain SM

J Comput Chem, 2011 Jul 15;32(9):1813-23.
PMID: 21455954 DOI: 10.1002/jcc.21763

The mechanism and enantioselectivity of the organocatalytic Diels-Alder reaction were computationally investigated by density functional theory at the B3LYP/6-31G(d) level of theory. The uncatalyzed Diels-Alder reaction was also studied to explore the effect of the organocatalyst on this reaction in terms of energetics, selectivity, and mechanism. The catalyzed reaction showed improved endo/exo selectivity, and the free energy of activation was significantly lowered in the presence of the catalyst. Both uncatalyzed and catalyzed reactions exhibited concerted asynchronous reaction mechanism with the degree of asynchronicity being more evident in the presence of the catalyst. The Corey's experimentally derived predictive selection rules for the outcome of the organocatalytic Diels-Alder reaction were also theoretically analyzed, and an excellent agreement was found between experiment and theory.
Ozonation of parabens in aqueous solution: kinetics and mechanism of degradation

Tay KS, Rahman NA, Abas MR

Chemosphere, 2010 Dec;81(11):1446-53.
PMID: 20875662 DOI: 10.1016/j.chemosphere.2010.09.004

This study investigated the reaction kinetics and degradation mechanism of parabens (methylparaben, ethylparaben, propylparaben and butylparaben) during ozonation. Experiments were performed at pH 2, 6 and 12 to determine the rate constants for the reaction of protonated, undissociated and dissociated paraben with ozone. The rate constants for the reaction of ozone with dissociated parabens (3.3 × 10(9)-4.2 × 10(9)M(-1)s(-1)) were found to be 10(4) times higher than the undissociated parabens (2.5 × 10(5)-4.4 × 10(5)M(-1)s(-1)) and 10(7) times higher than with the protonated parabens (1.02 × 10(2)-1.38 × 10(2)M(-1)s(-1)). The second-order rate constants for the reaction between parabens with hydroxyl radicals were found to vary from 6.8 × 10(9) to 9.2 × 10(9)M(-1)s(-1). Characterization of degradation by-products (DBPs) formed during the ozonation of each selected parabens has been carried out using GCMS after silylation. Twenty DBPs formed during ozonation of selected parabens have been identified. Hydroxylation has been found to be the major reaction for the formation of the identified DBPs. Through the hydroxylation reaction, a variety of hydroxylated parabens was formed.
Fulltext 2-[4-Acetyl-5-(biphenyl-4-yl)-4,5-dihydro-1,3,4-oxadiazol-2-yl]phenyl acetate

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2010 Mar 20;66(Pt 4):o878.
PMID: 21580697 DOI: 10.1107/S1600536810009621

In the title mol-ecule, C(24)H(20)N(2)O(4), the five-membered oxadiazole ring is nearly planar (r.m.s. deviation = 0.053 Å) and the phenyl ring of the biphenyl unit attached to it forms a dihedral angle of 73.2 (1)°; the other phenyl ring is close to coplanar with the oxadiazole ring [dihedral angle = 6.2 (2)°].
Fulltext N'-[(Biphenyl-4-yl)methyl-ene]-2-[(3,5-di-tert-butyl-4-hydroxy-benz-yl)sulfan-yl]acetohydrazide

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2010;66(Pt 4):o734.
PMID: 21580580 DOI: 10.1107/S1600536810006884

In the title compound, C(30)H(36)N(2)O(2)S, the dihedral angle between the two aromatic rings of the biphenyl residue is 31.2 (1)°. The two methyl-ene C atoms subtend an angle of 99.9 (1)° at the S atom. In the crystal, mol-ecules form inversion dimers linked by pairs of N-H⋯O hydrogen bonds. The hydroxyl group is shielded by the tert-butyl residues and is therefore not involved in any hydrogen bonding.
Degradation of DEET by ozonation in aqueous solution

Tay KS, Rahman NA, Abas MR

Chemosphere, 2009 Aug;76(9):1296-302.
PMID: 19570564 DOI: 10.1016/j.chemosphere.2009.06.007

This study was undertaken in order to understand the factors affecting the degradation of an insect repellent, N,N-diethyl-m-toluamide (DEET) by ozonation. Kinetic studies on DEET degradation were carried out under different operating conditions, such as varied ozone doses, pH values of solution, initial concentrations of DEET, and solution temperatures. The degradation of DEET by ozonation follows the pseudo-first-order kinetic model. The rate of DEET degradation increased exponentially with temperature in the range studied (20-50 degrees C) and in proportion with the dosage of ozone applied. The ozonation of DEET under different pH conditions in the presence of phosphate buffer occurred in two stages. During the first stage, the rate constant, k(obs), increased with increasing pH, whereas in the second stage, the rate constant, k(obs2), increased from pH 2.3 up to 9.9, however, it decreased when the pH value exceeded 9.9. In the case where buffers were not employed, the k(obs) were found to increase exponentially with pH from 2.5 to 9.2 and the ozonation was observed to occur in one stage. The rate of degradation decreased exponentially with the initial concentration of DEET. GC/MS analysis of the by-products from DEET degradation were identified to be N,N-diethyl-formamide, N,N-diethyl-4-methylpent-2-enamide, 4-methylhex-2-enedioic acid, N-ethyl-m-toluamide, N,N-diethyl-o-toluamide, N-acetyl-N-ethyl-m-toluamide, N-acetyl-N-ethyl-m-toluamide 2-(diethylamino)-1-m-tolylethanone and 2-(diethylcarbamoyl)-4-methylhex-2-enedioic acid. These by-products resulted from ozonation of the aliphatic chain as well as the aromatic ring of DEET during the degradation process.
Fulltext Dipyridinium 2,2'-dithio-dinicotinate

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2009;65(Pt 5):o1068.
PMID: 21583884 DOI: 10.1107/S1600536809013543

The dianion of the title salt, 2C(5)H(6)N(+)·C(12)H(6)N(2)O(4)S(2) (2-), lies on a special position of 2 site symmetry that relates one thio-nicotinate part to the other, and the dihedral angle between the niotinate planes is 89.2 (2)°. The pyridinium cations are hydrogen bonded to the carboxyl-ate group by way of N-H⋯O links.
Fulltext 2-(3,5-Di-tert-butyl-4-hydroxy-benzyl-sulfan-yl)-N'-(3-methoxy-benzyl-idene)acetohydrazide

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2009;65(Pt 9):o2112.
PMID: 21577527 DOI: 10.1107/S1600536809030645

The title compound, C(25)H(34)N(2)O(3)S, is a derivative of N'-benzyl-ideneacetohydrazide having substituents on the acetyl and benzylidenyl parts, and displays a planar C(carbon-yl)-NH-NC(anis-yl) fragment [torsion angle = 174.9 (3)°]. The -NH- unit forms an N-H⋯O hydrogen bond with the carbonyl O atom of an inversion-related mol-ecule.
Fulltext Biphenyl-4-carbaldehyde azine

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008;64(Pt 12):o2444.
PMID: 21581412 DOI: 10.1107/S1600536808038622

The complete mol-ecule of the title compound, C(26)H(20)N(2), is generated by crystallographic inversion symmetry. The terminal phenyl ring is twisted by 19.2 (1)° with respect to the adjacent phenyl-ene ring.
Fulltext N'-(3-Bromo-5-chloro-2-hydroxy-benzyl-idine)-2-hydroxy-benzohydrazide

Yehye WA, Ariffin A, Rahman NA, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008;64(Pt 12):o2438.
PMID: 21581406 DOI: 10.1107/S1600536808038634

In the approximately planar title mol-ecule, C(14)H(10)BrClN(3)O(2), the dihedral angle between the aromatic ring planes is 5.79 (12)°. The conformation is stabilized by intra-molecular O-H⋯N and N-H⋯O hydrogen bonds and an inter-molecular O-H⋯O link leads to chains in the crystal propagating in [001].
Fulltext Pheophorbide b ethyl ester from a chlorella vulgaris dietary supplement

Chee CF, Rahman NA, Zain SM, Ng SW

Acta Crystallogr Sect E Struct Rep Online, 2008;64(Pt 10):o1986.
PMID: 21201185 DOI: 10.1107/S160053680802970X

In the title compound, C(37)H(38)N(4)O(6), four five-membered nitro-gen-bearing rings are nearly coplanar. Two N atoms in two these five-membered rings have attached H atoms, which contribute to the formation of intra-molecular N-H⋯N hydrogen bonds [N⋯N = 2.713 (5)-3.033 (6) Å].
Analysis of secondary structure predictions of dengue virus type 2 NS2B/NS3 against crystal structure to evaluate the predictive power of the in silico methods

Othman R, Wahab HA, Yusof R, Rahman NA

In Silico Biol. (Gedrukt), 2007;7(2):215-24.
PMID: 17688447

Multiple sequence alignment was performed against eight proteases from the Flaviviridae family using ClustalW to illustrate conserved domains. Two sets of prediction approaches were applied and the results compared. Firstly, secondary structure prediction was performed using available structure prediction servers. The second approach made use of the information on the secondary structures extracted from structure prediction servers, threading techniques and DSSP database of some of the templates used in the threading techniques. Consensus on the one-dimensional secondary structure of Den2 protease was obtained from each approach and evaluated against data from the recently crystallised Den2 NS2B/NS3 obtained from the Protein Data Bank (PDB). Results indicated the second approach to show higher accuracy compared to the use of prediction servers only. Thus, it is plausible that this approach is applicable to the initial stage of structural studies of proteins with low amino acid sequence homology against other available proteins in the PDB.

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