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  1. Fulltext Crystal structure of 2'-hy-droxy-aceto-phenone 4-methyl-thio-semicarbazide
    Jamsari J, Abas NF, Ravoof TB, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2015 Apr 1;71(Pt 4):o244-5.
    PMID: 26029436 DOI: 10.1107/S2056989015004958
    In the organic mol-ecule of the title hydrate, C11H15N3OS·H2O, {systematic name: 3-ethyl-1-{(E)-[1-(2-hy-droxy-phen-yl)ethyl-idene]amino}-thio-urea monohydrate}, a dihedral angle of 5.39 (2)° is formed between the hy-droxy-benzene ring and the non-H atoms comprising the side chain (r.m.s. deviation = 0.0625 Å), with the major deviation from planarity noted for the terminal ethyl group [the C-N-C-C torsion angle = -172.17 (13)°]. The N-H H atoms are syn and an intra-molecular hy-droxy-imine O-H⋯N hydrogen bond is noted. In the crystal, the N-bonded H atoms form hydrogen bonds to symmetry-related water mol-ecules, and the latter form donor inter-actions with the hy-droxy O atom and with a hy-droxy-benzene ring, forming a O-H⋯π inter-action. The hydrogen bonding leads to supra-molecular tubes aligned along the b axis. The tubes are connected into layers via C-H⋯O inter-actions, and these stack along the c axis with no directional inter-actions between them.
  2. Does Order of Application of Emollient and Topical Corticosteroids Make a Difference in the Severity of Atopic Eczema in Children?
    Ng SY, Begum S, Chong SY
    Pediatr Dermatol, 2016 Mar;33(2):160-4.
    PMID: 26856694 DOI: 10.1111/pde.12758
    Atopic eczema (AE) is a common chronic inflammatory skin disorder in children, with emollients and topical corticosteroids (TCSs) commonly prescribed as treatment. There is no published guidance on the correct order of application of emollient and TCS in children with AE.
  3. Successful treatment of paediatric generalized pustular psoriasis with secukinumab: a case series
    Albela H, Begum S, Leong KF
    J Dermatolog Treat, 2021 Mar 11.
    PMID: 33706651 DOI: 10.1080/09546634.2021.1899111
    Generalized Pustular Psoriasis (GPP) is a rare, severe, life-threatening form of psoriasis and accounts for up to 13.1% of all childhood psoriasis. Common first-line systemic treatment for pediatric patients with GPP include oral acitretin, cyclosporin and methotrexate which have varying efficacy and side effects but multiple interventions are often needed to induce remission and maintain long term control. Recently, the anti IL 17 A monoclonal antibody secukinumab have been shown to be effective in adult patients with GPP; however, there is lack of evidence of its usage in the pediatric population. We describe a case series of 4 pediatric patients with GPP who were treated with off-label use of secukinumab. All four patients had marked clearance and reduction in Generalized Pustular Psoriasis Area & Severity Score (GPPASI) within first 48 h of first injection with subsequent almost complete to complete clearance of skin lesions by 1 month follow up. In conclusion, secukinumab was found to be successful in inducing remission, with rapid clearance and maintaining remission, with or without combination with other systemic agents for pediatric GPP.
  4. Fulltext Crystal structure of 2-{[2-(3-phenyl-allyl-idene)hydrazin-1-yl]thio-carbonyl-sulfanylmeth-yl}pyridinium chloride
    Low ML, Ravoof TB, Tahir MI, Crouse KA, Tiekink ER
    Acta Crystallogr Sect E Struct Rep Online, 2014 Nov 1;70(Pt 11):o1207-8.
    PMID: 25484832 DOI: 10.1107/S1600536814023228
    In the title salt of an S-substituted di-thio-carbazate, C16H16N3S2 (+)·Cl(-), the dihedral angles between the almost planar (r.m.s deviation = 0.005 Å) central CN2S2 residue and the terminal pyridinium and phenyl rings are 80.09 (11) and 3.82 (11)°, respectively, indicating the cation has an L-shape; the amine H and thione S atoms are syn. The conformation about each of the imine [1.376 (3) Å] and ethene [1.333 (4) Å] bonds is E. The shortened C-C bond [1.444 (4) Å] linking the double bonds is consistent with conjugation in this part of the mol-ecule. In the crystal, supra-molecular layers with a jagged topology are formed by charged-assisted amine-H⋯Cl(-) and pyridinium-N(+)-H⋯Cl(-) hydrogen bonds. The layers stack along the a axis with no specific directional inter-actions between them.
  5. Fulltext 2-Cyclo-hexyl-idene-N-methyl-hydrazine-carbothio-amide
    Tayamon S, Mazlan NA, Ravoof TB, Mohamed Tahir MI, Crouse KA
    Acta Crystallogr Sect E Struct Rep Online, 2012 Nov 1;68(Pt 11):o3104-5.
    PMID: 23284431 DOI: 10.1107/S1600536812042018
    The title compound C(8)H(15)N(3)S has two mol-ecules in the asymmetric unit in which cis-trans isomerism is exhibited around the N(NH)C=S bonds. The cyclo-hexyl rings in both mol-ecules adopt a chair conformation. In the crystal, N-H⋯S hydrogen bonding produces dimers, which are inter-connected through further N-H⋯S hydrogen bonds, forming chains along the b-axis direction.
  6. Fulltext 2,2-Dibenzyl-hydrazin-1-ium chloride
    Tayamon S, Ravoof TB, Tahir MI, Crouse KA, Tiekink ER
    Acta Crystallogr Sect E Struct Rep Online, 2013 Mar 1;69(Pt 3):o382.
    PMID: 23476568 DOI: 10.1107/S1600536813003966
    In the title salt, C14H17N2(+)·Cl(-), the central N atom is pyramidal (sum of bond angles = 330.9°) and there is a near orthogonal relationship between the benzene rings [dihedral angle = 89.95 (10)°]. The crystal packing features N-H⋯Cl hydrogen bonds, which lead to a supra-molecular undulating ribbon along the a axis comprising edge-shared eight-membered {⋯HNH⋯Cl}2 synthons. The chains are connected into layers in the ab plane by C-H⋯π inter-actions.
  7. Fulltext (Pyridin-4-yl)methyl N'-(3-phenyl-allyl-idene)hydrazinecarbodithio-ate
    Low ML, Ravoof TB, Tahir MI, Crouse KA, Tiekink ER
    Acta Crystallogr Sect E Struct Rep Online, 2013 Feb 1;69(Pt 2):o167-8.
    PMID: 23424455 DOI: 10.1107/S1600536812051537
    In the title compound, C(16)H(15)N(3)S(2), the central C(2)N(2)S(2) residue is planar (r.m.s. deviation = 0.045 Å) and the pyridyl and benzene rings are inclined and approximately coplanar to this plane, respectively [dihedral angles = 72.85 (9) and 10.73 (9)°], so that, overall, the mol-ecule adopts an L-shape. The conformation about each of the N=C [1.290 (3) Å] and C=C [1.340 (3) Å] bonds is E. Supra-molecular chains along [1-10] are stabilized by N-H⋯N(pyridine) hydrogen bonding and these are connected into a double layer that stacks along the c-axis direction by C-H⋯π(pyridine) inter-actions.
  8. Fulltext Crystal structure of 4-methyl-benzyl N'-[(thio-phen-2-yl)methyl-idene]hydrazinecarbodi-thio-ate
    Ramli SB, Ravoof TB, Tahir MI, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2015 Jul 1;71(Pt 7):o475-6.
    PMID: 26279916 DOI: 10.1107/S205698901501107X
    In the title compound, C15H16N2S3 {systematic name: [({[(4-methyl-phen-yl)meth-yl]sulfan-yl}methane-thio-yl)amino][1-(thio-phen-2-yl)ethyl-idene]amine}, the central CN2S2 residue is almost planar (r.m.s. deviation = 0.0061 Å) and forms dihedral angles of 7.39 (10) and 64.91 (5)° with the thienyl and p-tolyl rings, respectively; the dihedral angle between these rings is 57.52 (6)°. The non-thione S atoms are syn, and with respect to the thione S atom, the benzyl group is anti. In the crystal, centrosymmetrically related mol-ecules self-associate via eight-membered {⋯HNCS}2 synthons. The dimeric aggregates stack along the a axis and are are consolidated into a three-dimensional architecture via methyl-C-H⋯π(benzene) and benzene-C-H⋯π(thien-yl) inter-actions.
  9. Fulltext Crystal structure of (Z)-4-methylbenzyl 3-[1-(5-methylpyridin-2-yl)ethylidene]dithiocarbazate
    Ravoof TB, Tiekink ER, Omar SA, Begum SZ, Tahir MI
    Acta Crystallogr E Crystallogr Commun, 2015 Dec 1;71(Pt 12):o1071-2.
    PMID: 26870503 DOI: 10.1107/S205698901502407X
    In the title di-thio-carbazate compound, C17H19N3S2, the central CN2S2 residue is essentially planar (r.m.s. deviation = 0.0288 Å) and forms dihedral angles of 9.77 (8) and 77.47 (7)° with the substituted-pyridyl and p-tolyl rings, respectively, indicating a highly twisted mol-ecule; the dihedral angle between the rings is 85.56 (8)°. The configuration about the C=N bond is Z, which allows for the formation of an intra-molecular N-H⋯N(pyrid-yl) hydrogen bond. The packing features tolyl-methyl-C-H⋯N(imine), pyridyl-C-H⋯π(tol-yl) and π-π inter-actions [between pyridyl rings with a distance = 3.7946 (13) Å], which generates jagged supra-molecular layers that stack along the b axis with no directional inter-actions between them.
  10. Fulltext Crystal structure of 1-{(Z)-[(2E)-3-(4-chloro-phen-yl)-1-phenyl-prop-2-en-1-yl-idene]amino}-3-ethyl-thio-urea
    Tan MY, Crouse KA, Ravoof TB, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2015 Dec 1;71(Pt 12):o1047-8.
    PMID: 26870491 DOI: 10.1107/S2056989015023531
    In the title thio-semicarbazone compound, C18H18ClN3S, the CN3S residue is almost planar (r.m.s. deviation = 0.0031 Å) and forms dihedral angles of 65.99 (7) and 34.60 (10)° with the phenyl and chloro-benzene rings, respectively; the dihedral angle between the aromatic rings is 85.13 (8)°. The conformation about the C=N bond is Z, and that about the C=C bonds is E. The imine N and ethyl N atoms are syn and are linked by an eth-yl-imine N-H⋯N hydrogen bond. This H atom also forms an inter-molecular hydrogen bond to the thione S atom, resulting in a supra-molecular helical chain propagating along the b axis. The chains are consolidated into a three-dimensional architecture by phenyl-C-H⋯Cl contacts and weak π-π inter-actions between centrosymmetrically related chloro-benzene rings [inter-centroid distance = 3.9127 (15) Å].
  11. Fulltext Crystal structure of benzyl 3-(3-methyl-phen-yl)di-thio-carbazate
    Aziz NA, Yusof EN, Ravoof TB, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2015 Apr 1;71(Pt 4):o233-4.
    PMID: 26029430 DOI: 10.1107/S2056989015004764
    In the title compound, C15H16N2S2, the central CN2S2 residue is almost planar (r.m.s. deviation = 0.0354 Å) and forms dihedral angles of 56.02 (4) and 75.52 (4)° with the phenyl and tolyl rings, respectively; the dihedral angle between the aromatic rings is 81.72 (5)°. The conformation about the N-N bond is gauche [C-N-N-C = -117.48 (15)°]. Overall, the mol-ecule has the shape of the letter L. In the crystal packing, supra-molecular chains along the a axis are formed by N-H⋯S(thione) hydrogen bonds whereby the thione S atom accepts two such bonds. The hydrogen bonding leads to alternating edge-shared eight-membered {⋯HNCS}2 and 10-membered {⋯HNNH⋯S}2 synthons. The chains are connected into layers by phen-yl-tolyl C-H⋯π inter-actions; the layers stack along the c axis with no specific inter-actions between them.
  12. Fulltext Crystal structure of 3-methyl-pyridine-2-carbaldehyde 4-methyl-thio-semi-carba-zone monohydrate
    Mokhtaruddin NS, Ravoof TB, Tahir MI, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2015 Apr 1;71(Pt 4):o253-4.
    PMID: 26029441 DOI: 10.1107/S2056989015005034
    In the title hydrate, C9H12N4S·H2O (systematic name: 3-methyl-1-{(E)-[(3-methyl-pyridin-2-yl)methyl-idene]amino}-thio-urea monohydrate), a small twist is noted between the pyridine ring and the rest of the organic mol-ecule [dihedral angle = 6.96 (5)°]. The imine and pyridine N atoms are syn, and the amine H atoms are anti. The latter arrangement allows for the formation of an intra-molecular N-H⋯N(imine) hydrogen bond. Both the N-bonded H atoms form hydrogen bonds to symmetry-related water mol-ecules, and the latter forms O-H hydrogen bonds with the pyridine N and thione S atoms. These inter-actions lead to supra-molecular layers that stack along the a-axis direction with no specific inter-actions between them.
  13. Fulltext Crystal structure of 2-((1E)-{2-[bis-(2-methyl-benzyl-sulfan-yl)methyl-idene]hydrazin-1-yl-idene}meth-yl)-6-meth-oxy-phenol
    Yusof EN, Ravoof TB, Tahir MI, Tiekink ER
    Acta Crystallogr E Crystallogr Commun, 2015 Apr 1;71(Pt 4):o242-3.
    PMID: 26029435 DOI: 10.1107/S2056989015004946
    In the title compound, C25H26N2O2S2, the central CN2S2 atoms are almost coplanar (r.m.s. deviation = 0.0058 Å). One phenyl ring clearly lies to one side of the central plane, while the other is oriented in the plane but splayed. Despite the different relative orientations, the phenyl rings form similar dihedral angles of 64.90 (3) and 70.06 (3)° with the central plane, and 63.28 (4)° with each other. The benzene ring is twisted with respect to the central plane, forming a dihedral angle of 13.17 (7)°. The S2C=N, N-N and N-N=C bond lengths of 1.2919 (19), 1.4037 (17) and 1.2892 (19) Å, respectively, suggest limited conjugation over these atoms; the configuration about the N-N=C bond is E. An intra-molecular O-H⋯N hydrogen bond is noted. In the crystal, phen-yl-meth-oxy C-H⋯O and phen-yl-phenyl C-H⋯π inter-actions lead to supra-molecular double chains parallel to the b axis. These are connected into a layer via meth-yl-phenyl C-H⋯π inter-actions, and layers stack along the a axis, being connected by weak π-π inter-actions between phenyl rings [inter-centroid distance = 3.9915 (9) Å] so that a three-dimensional architecture ensues.
  14. Fulltext Bis{S-benzyl 3-[(6-methyl-pyridin-2-yl)methyl-idene]dithio-carbazato}nickel(II)
    Ravoof TB, Omar SA, Mohamed Tahir MI, Crouse KA
    Acta Crystallogr Sect E Struct Rep Online, 2012 May 01;68(Pt 5):m664.
    PMID: 22590148 DOI: 10.1107/S1600536812017333
    The asymmetric unit of the title compound, [Ni(C(15)H(14)N(3)S(2))(2)], consists of two independent mol-ecules with similar configurations. Each Ni(2+) cation is coordinated in a cis-mode by two tridentate N,N',S-chelating Schiff base ligands, creating a distorted octa-hedron [the smallest angle being 77.57 (7)° and the widest being 168.97 (7)° for one mol-ecule, and 78.04 (7) and 167.55 (7)° for the second mol-ecule]. The dihedral angle between the mean coordination planes of the two ligands is 86.76 (7)° for one and 89.99 (7)° for the second mol-ecule. π-π inter-actions between neighbouring pyridine rings with plane-to-plane distances of 3.540 (1) and 3.704 (1) Å are observed.
  15. Fulltext Efficacy and Tolerability of Methotrexate in the Treatment of Severe Paediatric Alopecia Areata
    Albela H, Begum S, Wee AL, Ponnuthurai N, Leong KF
    Skin Appendage Disord, 2022 May;8(3):206-210.
    PMID: 35707294 DOI: 10.1159/000521238
    INTRODUCTION: Alopecia areata (AA) is a chronic, autoimmune condition affecting hair follicles, and its occurrence in the paediatric population is associated with poorer prognosis and limited treatment options compared to adults. Treatment with oral methotrexate (MTX) has been documented in adults, but there is a paucity of data for its use in the paediatric population. We aimed to study the efficacy and tolerability of MTX in severe paediatric AA.

    METHODS: We performed a retrospective review on paediatric patients with severe AA who were treated with MTX in our centre from January 2019 to December 2020.

    RESULTS: Thirteen patients were included (6 boys and 7 girls) aged between 4 and 16 years at the initiation of MTX (mean age of 8.8 years). The interval from diagnosis of AA to commencement of MTX was between 8 months and 9 years (mean duration of 3.3 years). Oral MTX was administered once weekly with a mean maximal dose of 0.4 mg/kg/dose. Out of 12 assessable patients, 5 were considered treatment success as they had more than 50% regrowth, while the other 7 were treatment failures. No serious side effects were reported.

    CONCLUSION: MTX was shown to have variable efficacy for the treatment of paediatric AA with overall good tolerability. MTX can be considered in the treatment of severe refractory AA for children.

  16. Fulltext Study of genetic variation of eggplant cultivars by using RAPD-PCR molecular markers and the relationship with Phomopsis blight disease reaction
    Asad HA, Meah MB, Begum SN, Khalil MI, Rafii MY, Latif MA
    Genet. Mol. Res., 2015;14(4):17007-18.
    PMID: 26681048 DOI: 10.4238/2015.December.16.1
    Disease susceptibility and genetic variability in 10 eggplant genotypes were studied after inoculating Phomopsis vexans under confined field conditions. Random amplified polymorphic DNA (RAPD) markers were used to assess genetic variation and relationships among eggplant genotypes. The disease index of leaves ranged 0.208-13.79%, while fruit infection ranged 2.15-42.76%. Two varieties, Dohazari G and Laffa S, were found to be susceptible, 6 were moderately resistant, 1 was moderately susceptible, and BAU Begun-1 was resistant to P. vexans. Amplification of genomic DNA by using 3 RAPD primers produced 20 bands: 14 (70%) were polymorphic and 6 (30%) were monomorphic. The highest intra-variety similarity indices values were found in ISD 006, Ishurdi L, Jessore L, and BAU Begun-1 (100%), while the lowest was in Dohazari G (90%). The lowest genetic distance (0.0513) and the highest genetic identity (0.9500) were observed between the ISD 006 and Ishurdi L combinations. A comparatively higher genetic distance (0.3724) and the lowest genetic identity (0.6891) were observed between the ISD 006 and Dohazari G combinations. A dendogram was constructed based on Nei's genetic distance, which produced 2 main clusters of the genotypes - Cluster I: ISD 006, Ishurdi L, Marich begun L, BAU Begun-1, Marich begun S, and Chega and Cluster 2: Laffa S, Dohazari G, Jessore L, and Singhnath. Genetic variation and its relationship with disease susceptibility were assessed using RAPD markers, to develop disease-resistant varieties and improve eggplant crops.
  17. Transcription profile of genes affected in response to pathological changes in drug-induced rat model of acute kidney injury
    Habib R, Begum S, Alam G, Ali A, Khan I, Waseem M, et al.
    Ren Fail, 2015 Aug;37(7):1225-31.
    PMID: 26114661 DOI: 10.3109/0886022X.2015.1057801
    The objective of the present study was to examine the changes in the expression profile of certain genes in rat model of gentamicin-induced acute kidney injury (AKI) and to see whether time period and routes of administration affect their expression levels.
  18. Factor V inhibitor in neonatal intracranial hemorrhage secondary to severe congenital factor V deficiency
    Lee WS, Chong LA, Begum S, Abdullah WA, Koh MT, Lim EJ
    J Pediatr Hematol Oncol, 2001 May;23(4):244-6.
    PMID: 11846304
    We report a newborn infant girl, born to consanguineous parents, with recurrent intracranial hemorrhage secondary to congenital factor V deficiency with factor V inhibitor. Repeated transfusions of fresh-frozen plasma (FFP) and platelet concentrates, administrations of immunosuppressive therapy (prednisolone and cyclophosphamide), and intravenous immunoglobulin failed to normalize the coagulation profiles. Exchange transfusion followed-up by administrations of activated prothrombin complex and transfusions of FFP and platelet concentrates caused a temporary normalization of coagulation profile, enabling an insertion of ventriculoperitoneal (VP) shunt for progressive hydrocephalus. The treatment was complicated by thrombosis of left brachial artery and ischemia of left middle finger. The child finally died from another episode of intracranial hemorrhage 10 days after insertion of the VP shunt.
  19. Review of chitosan composite as a heavy metal adsorbent: Material preparation and properties
    Begum S, Yuhana NY, Md Saleh N, Kamarudin NHN, Sulong AB
    Carbohydr Polym, 2021 May 01;259:117613.
    PMID: 33673980 DOI: 10.1016/j.carbpol.2021.117613
    A large amount of wastewater is typically discharged into water bodies and has extremely harmful effects to aquatic environments. The removal of heavy metals from water bodies is necessary for the safe consumption of water and human activities. The demand for seafood has considerably increased, and millions of tons of crustacean waste are discarded every year. These waste products are rich in a natural biopolymer known as chitin. The deacetylated form of chitin, chitosan, has attracted attention as an adsorbent. It is a biocompatible and biodegradable polymer that can be modified and converted to various derivatives. This review paper focuses on relevant literature on strategies for chemically modifying the biopolymer and its use in the removal of heavy metals from water and wastewater. The different aspects of chitosan-based derivatives and their preparation and application are elucidated. A list of chitosan-based composites, along with their adsorptivity and experimental conditions, are compiled.
  20. Fulltext Bedtime Smart Phone Usage and Its Effects on Work-Related Behaviour at Workplace
    Ellahi A, Javed Y, Begum S, Mushtaq R, Rehman M, Rehman HM
    Front Psychol, 2021;12:698413.
    PMID: 34484046 DOI: 10.3389/fpsyg.2021.698413
    The over usage and over dependency on digital devices, like smartphones, has been considered as a growing international epidemic. The increased dependency on gadgets, especially smartphones for personal and official uses, has also brought many detrimental effects on individual users. Hence it is vital to understand the negative effects of smartphone usage on human. Therefore, this study aims to investigate the effects of bedtime smartphone usage on work performances, interpersonal conflicts, and work engagement, via the mediating role of sleep quality among employees. Using a cross-sectional study design, a questionnaire-based field survey was conducted on 315 employees who participated as respondents. The results confirmed the negative effects of bedtime smartphone usage on sleep quality. Along with it, the effects of sleep quality on work performances, work engagements and interpersonal conflicts were also proven to be statistically significant. Regarding the mediating role of sleep quality, it was empirically evident that sleep quality mediates the relationship between bedtime smartphone usage with work performances and interpersonal conflicts. The findings revealed that bedtime smartphone usage reduces sleep quality among the employees, resulting in lower work performances and engagements while contributing to higher interpersonal conflicts. The findings concluded that smartphone usage before sleep increases the prospects of employees to be less productive, less engaged, and have more workplace conflicts. The findings warrant the continued managerial as well as academic research attention, as the smartphones are now used by many organisations to run businesses as well.
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