Displaying all 14 publications

Abstract:
Sort:
  1. Khan TF, Zahari A
    Med J Malaysia, 1993 Jun;48(2):244-7.
    PMID: 8350806
    Details of a young logger who sustained a clean prevertebral transection of the pancreas to the left of the superior mesenteric vessels and a crush injury in segments 2 and 3 of the liver are presented. CT scan was not done but ultrasound scan revealed free intraperitoneal fluid and no comment was made about the pancreas. The pancreatic injury was discovered at laparotomy carried out 24 hours after admission and treated by resection.
  2. Toufeeq Khan TF, Lwin M, Ulah S, Zahari A, Mokti I
    Singapore Med J, 1993 Dec;34(6):545-50.
    PMID: 8153721
    Twenty bilio-enteric anastomoses were performed or managed from May 1990 to December 1992. Recurrent pyogenic cholangitis (RPC) and pancreatic cancer were the commonest conditions which required drainage procedures. Roux-en-Y hepatico-jejunostomy (RHJ) was performed in 9 patients, 4 for RPC, one for pancreatic cancer, another for a cholangiocarcinoma, 2 following excision of choledochal cyst and one hepatico-jejunostomy was part of a Whipple reconstruction. Roux-en-Y side to side choledocho-jejunostomy (CDJ) was performed in one patient. Choledocho-duodenostomy (CDD) was performed in 6, 4 for obstructive jaundice due to choledocholithiasis, one for RPC and one in a choledochal cyst. One patient operated elsewhere presented with complications after a CDD. Palliative cholecysto-jejunostomy (CYJ) was carried out in 4 patients with pancreatic malignancy. All benign conditions were treated by hepatico-jejunostomy and choledocho-duodenostomy, while three patients with malignant conditions were treated by hepatico-jejunostomy. Permanent subcutaneous access loops were provided when recurrent problems were anticipated, 4 in RPC and one after subtotal resection of a cholangiocarcinoma. Based on this study, we found Roux-en-Y hepatico-jejunostomy a versatile drainage procedure, which was useful in both benign and malignant diseases.
  3. Khan TF, Zahari A, Sherazi ZA, Visvanathan R
    Singapore Med J, 1993 Oct;34(5):462-3.
    PMID: 8153702
    This is a report of a 57-year-old Malay lady who presented with recurrent episodes of cholangitis and septicaemia. A dilated biliary tree caused by a stenosing periampullary tumour was found to contain adult round worms. A pancreatico-duodenectomy was performed following biliary decompression. Ascarid worms are a rare cause of cholangitis in malignant biliary obstruction.
  4. Nasrullah AA, Zahari A, Mohamad J, Awang K
    Molecules, 2013 Jul 08;18(7):8009-17.
    PMID: 23884132 DOI: 10.3390/molecules18078009
    A dichloromethane extract of the stem bark of Cryptocarya nigra showed strong in vitro inhibition of Plasmodium falciparum growth, with an IC50 value of 2.82 μg/mL. The phytochemical study of this extract has led to the isolation and characterization of four known alkaloids: (+)-N-methylisococlaurine (1), atherosperminine (2), 2-hydroxyathersperminine (3), and noratherosperminine (4). Structural elucidation of all alkaloids was accomplished by means of high field 1D- and 2D-NMR, IR, UV and LCMS spectral data. The isolated extract constituents (+)-N-methylisococlaurine (1), atherosperminine (2) and 2-hydroxy-atherosperminine (3) showed strong antiplasmodial activity, with IC50 values of 5.40, 5.80 and 0.75 μM, respectively. In addition, (+)-N-methylisocolaurine (1) and atherosperminine (2) showed high antioxidant activity in a DPPH assay with IC50 values of 29.56 ug/mL and 54.53 ug/mL respectively. Compounds 1 and 2 also both showed high antioxidant activity in the FRAP assay, with percentages of 78.54 and 70.66 respectively and in the metal chelating assay, with IC50 values of 50.08 ug/mL and 42.87 ug/mL, respectively.
  5. Zahari A, Ablat A, Sivasothy Y, Mohamad J, Choudhary MI, Awang K
    Asian Pac J Trop Med, 2016 Apr;9(4):328-332.
    PMID: 27086149 DOI: 10.1016/j.apjtm.2016.03.008
    OBJECTIVE: To study antiplasmodial and antioxidant activities of the isolation of alkaloids from the active dichloromethane extract of Alseodaphne corneri.

    METHODS: Phytochemical studies of the crude extract led to the isolation of six alkaloids using recycle high performance liquid chromatography and preparative thin layer chromatography. The antiplasmodial activity of the isolated compounds was evaluated using the histidine-rich protein II assay. The isolated alkaloids were also tested for their antioxidant activity using three different assays; DPPH, ferric reducing ability of plasma and metal chelating assays.

    RESULTS: Malaria infection caused the formation of free radicals which subsequently led to oxidative stress and apoptosis. The antioxidant properties of the alkaloids under investigation revealed that in addition to the antiplasmodial activity, the alkaloids could also prevent oxidative stress. (+)-laurotetanine and (+)-norstephasubine exhibited strong antiplasmodial activities with IC50 values of 0.189 and 0.116 μM, respectively.

    CONCLUSIONS: Interestingly, the two most potent compounds that exhibit antiplasmodial activity also exhibit good antioxidant activities. The crude dichloromethane extract and the isolated compounds exert substantial antiplasmodial and antioxidative activities which in turn suppress oxidative stress and cause less damage to the host.

  6. Zahari A, Ablat A, Omer N, Nafiah MA, Sivasothy Y, Mohamad J, et al.
    Sci Rep, 2016;6:21517.
    PMID: 26898753 DOI: 10.1038/srep21517
    The UV-vis spectra of isocorydine 1, norisocorydine 2 and boldine 3 were studied in 2% v/v acetonitrile, at constant ionic strength (0.1 M NaCl, 35 degree Celsius). The pK(a) values of isocorydine 1 and norisocorydine 2 were 11.75 and 12.07, respectively. Boldine 3 gave a pK(a) value of 9.16 and 10.44. All of the alkaloids 1-3 were stable at physiological pH; thereby all of them will not ionize, thus permitting the basic nitrogen to be protonated and accumulated within the acidic food vacuole of Plasmodium via pH trapping. Subsequently, acidic food vacuoles that have been neutralized by alkaloids would result in enhancement of the antiplasmodial activity. The alkaloids showed antiplasmodial activity against Plasmodium falciparum and antioxidant activities; DPPH radical scavenging, metal chelating and ferric reducing power. The antioxidant properties of the alkaloids under investigation revealed that in addition to the antiplasmodial activity, the alkaloids can also prevent oxidative damage. It can be prevented by binding free heme and neutralizing the electrons produced during the Plasmodium falciparum mediated haemoglobin destruction in the host. Slightly basic properties of the aforementioned alkaloids, along with their antioxidant activities, are advantageous in improving the suppression of malaria infection that cause less damage to the host.
  7. Azani NFSM, Haafiz MKM, Zahari A, Poinsignon S, Brosse N, Hussin MH
    Int J Biol Macromol, 2020 Jun 15;153:385-398.
    PMID: 32145234 DOI: 10.1016/j.ijbiomac.2020.03.020
    Oil palm frond (OPF) is one of largest contributions to the biomass waste from oil palm plantation. In this work, OPF has been successfully utilized to prepare cellulose nanocrystal (OPF-CNC) by acid hydrolysis. OPF was initially treated with autohydrolysis treatment. The obtained OPF-CNC was characterized via complementary analyses. The produced OPF-CNC showed a high crystallinity index value (60%) and high BET surface area (26.10 m2 g-1) as compared to α-cellulose (crystallinity index: 54% and BET surface area:7.14 m2g-1). The surface analyses via scanning electron microscope (SEM) and transmission electron microscopy (TEM) demonstrated that the OPF-CNC has a smooth surface with a needle-like shape, where the average length and diameter are 95.09 nm and 6.81 nm, respectively. The corrosion analyses via electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization (PD) illustrate that the coated mild steel with the inclusion of 0.5 wt% OPF-CNC has managed to sharply reduce the corrosion (99%). The coated mild steel with the inclusion of 0.5 wt% OPF-CNC showed the highest hydrophobicity (100.5 ± 0.7°) and has lowest amount of O via water contact angle and energy dispersive X-ray spectroscopy (EDX) analyses respectively, indicating lowest corrosion rate.
  8. Zahari A, Cheah FK, Mohamad J, Sulaiman SN, Litaudon M, Leong KH, et al.
    Planta Med, 2014 May;80(7):599-603.
    PMID: 24723007 DOI: 10.1055/s-0034-1368349
    The crude extract of the bark of Dehaasia longipedicellata exhibited antiplasmodial activity against the growth of Plasmodium falciparum K1 isolate (resistant strain). Phytochemical studies of the extract led to the isolation of six alkaloids: two morphinandienones, (+)-sebiferine (1) and (-)-milonine (2); two aporphines, (-)-boldine (3) and (-)-norboldine (4); one benzlyisoquinoline, (-)-reticuline (5); and one bisbenzylisoquinoline, (-)-O-O-dimethylgrisabine (6). Their structures were determined on the basis of 1D and 2D NMR, IR, UV, and LCMS spectroscopic techniques and upon comparison with literature values. Antiplasmodial activity was determined for all of the isolated compounds. They showed potent to moderate activity with IC50 values ranging from 0.031 to 30.40 µM. (-)-O-O-dimethylgrisabine (6) and (-)-milonine (2) were the two most potent compounds, with IC50 values of 0.031 and 0.097 µM, respectively, that were comparable to the standard, chloroquine (0.090 µM). The compounds were also assessed for their antioxidant activities with di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium (IC50 = 18.40-107.31 µg/mL), reducing power (27.40-87.40 %), and metal chelating (IC50 = 64.30 to 257.22 µg/mL) having good to low activity. (-)-O-O-dimethylgrisabine (6) exhibited a potent antioxidant activity of 44.3 % reducing power, while di(phenyl)-(2,4,6-trinitrophenyl)iminoazanium and metal chelating activities had IC50 values of 18.38 and 64.30 µg/mL, respectively. Thus it may be considered as a good reductant with the ability to chelate metal and prevent pro-oxidant activity. In addition to the antiplasmodial and antioxidant activities, the isolated compounds were also tested for their cytotoxicity against a few cancer and normal cell lines. (-)-Norboldine (4) exhibited potent cytotoxicity towards pancreatic cancer cell line BxPC-3 with an IC50 value of 27.060 ± 1.037 µM, and all alkaloids showed no toxicity towards the normal pancreatic cell line (hTERT-HPNE).
  9. Hamidon TS, Idris NN, Adnan R, Haafiz MKM, Zahari A, Hussin MH
    Int J Biol Macromol, 2024 Mar;262(Pt 2):130239.
    PMID: 38367788 DOI: 10.1016/j.ijbiomac.2024.130239
    Herein, cellulose nanocrystals were synthesized from oil palm fronds (CNC-OPF) involving two pretreatment approaches, viz. autohydrolysis and soda pulping. The pretreatments were applied individually to OPF fibers to assess their influence on CNCs' physicochemical and thermal properties. CNC-OPF samples were assessed using complementary characterization techniques, which confirmed their purity and characteristics. CP/MAS 13C NMR and TEM studies revealed that autohydrolysis pretreatment yielded CNCs with effective hemicellulose and extractives removal compared to that of soda pulping. XRD analysis demonstrated that autohydrolysis-treated CNC-OPF contained a much higher crystallinity index compared to soda pulping treatment. BET measurement disclosed a relatively higher surface area and wider pore diameter of autohydrolysis-treated CNC-OPF. Autohydrolysis-treated CNCs were applied as a reinforcement filler in alginate-based hydrogel beads for the removal of 4-chlorophenol from water, which attained a qmax of 19.168 mg g-1. BET analysis revealed the less porous nature of CNC-ALG hydrogel beads which could have contributed to hydrogel beads' relatively lower adsorption capacity. The point of zero charge of CNC-ALG hydrogel beads was 4.82, suggesting their applicability only within a short solution pH range. This study directs future studies to unveil the possibilities of functionalizing CNCs in order to enhance the adsorption performance of CNC-immobilized hydrogel beads towards 4-chlorophenol and other organic contaminants.
  10. Sulaiman SN, Mukhtar MR, Hadi AH, Awang K, Hazni H, Zahari A, et al.
    Molecules, 2011 Apr 13;16(4):3119-27.
    PMID: 21490559 DOI: 10.3390/molecules16043119
    A new bisbenzylisoquinoline, lancifoliaine (1), together with seven known alkaloids--N-allyllaurolitsine (2), reticuline (3), actinodaphnine, norboldine, pallidine, cassythicine and boldine--were isolated from the stem bark of Litsea lancifolia (Lauraceae). In addition to that of lancifoliaine, complete ¹³C-NMR data of N-allyl-laurolitsine (2) was also reported. The alkaloidal structures were elucidated by means of high field 1D- and 2D-NMR IR, UV, and LCMS-IT-TOF spectral data. N-Allyllaurolitsine (2) showed a moderate vasorelaxant activity on isolated rat aorta.
  11. Cheah WL, Francis Wing CB, Zahari AN, Idris AS, Maksul NAA, Yusman NAL, et al.
    Ethics Med Public Health, 2021 Jun;17:100651.
    PMID: 33754125 DOI: 10.1016/j.jemep.2021.100651
    Background: The COVID-19 pandemic has resulted in many changes in the delivery of health service which not only affect the public as well as healthcare workers, and also among medical and nursing students who are currently undergoing their training. This study aims to determine the commitment and willingness of medical and nursing students in Sarawak in treating patients with COVID-19 and its associated factors.

    Methods: It was a cross-sectional study using online questionnaire, carried out in a public university in Sarawak, Malaysia. All medical and nursing students were invited to participate in this study. Data was entered and analysed using IBM SPSS version 22.

    Result: A total of 304 respondents participated in the study, with 81.6% female and 69.4% medical students. Majority of the respondents were most willing to take a medical history, do a physical examination, throat swabbing, draw blood and perform IV drip insertion. There was a high commitment among respondents to treat COVID-19 patients regardless of personal risks. Majority of the respondents also agreed that medical staff who are involved in treating COVID-19 patients should be receiving a salary increase and compensation should be given to affected healthcare families, and all non-medical staff should be involved in treating COVID-19 patients. About 71% agreed about a law mandating medical staffs to treat patient.

    Conclusion: The willingness and commitment of medical and nursing students to treat COVID-19 patients was high, indicating their potential work force as healthcare providers.

  12. Sahid NA, Hayati F, Rao CV, Ramely R, Sani I, Dzulkarnaen A, et al.
    PMID: 30538757 DOI: 10.1155/2018/3032790
    BACKGROUND: Snakehead fish (Channa striatus) is a fresh water fish indigenous to many Asia countries and believed to have medical value. Studies showed that it contains all the essential amino acids and fatty acids able to accelerate wound healing and it has antinociceptive effect. However, little human study has been done to assess the effectiveness of Channa striatus in wound healing. A prospective RCT has been conducted on the effect of Channa striatus spray versus placebo on clean wound to assess its pain control effect and cosmetic outcome.

    METHODOLOGY: One hundred and two patients (102) underwent clean elective surgery; postoperatively they were randomized into two group. One group received Channa striatus extract spray (n=51) another group received placebo (n=51) on daily basis for 2 weeks. They were followed up on 2nd, 4th, and 6th weeks. Pain control effect was assessed based on Visual Analog Pain Score (VAPS) and cosmetic outcome based on Visual Analog Cosmetic Scale (VACS), Wound Evaluation Scale (WES), and Vancouver Scar Scale (VSS).

    RESULT: The patient treated with Channa striatus spray displayed a better outcome in terms of pain control compared to placebo. During analysis using repeated measure ANOVA, there was significant difference of patient's pain score based on VAPS between Channa striatus spray and placebo (F-stat (df) = 4.80 (2), p-value = 0.010). For cosmetic outcome it showed a better result in Channa striatus spray group for all the 3-scoring system, VACS, (F-stat (df) = 2.68 (2) , p-value <0.001), WES (F-stat (df) = 3.09 (2), p-value = 0.048), and VSS (F-stat (df) = 1.72 (2) , p-value = 0.011).

    CONCLUSION: Our study suggest that application of Channa striatus extract spray on clean wound has shown a significant better pain score result and cosmetic outcome on week 2, week 4, and week 6 comparatively with placebo.

  13. Osman N, Awang K, Khaw KY, Qi Mak W, Tiamas SG, Maulana S, et al.
    Nat Prod Res, 2024 Aug 21.
    PMID: 39165195 DOI: 10.1080/14786419.2024.2394096
    This study investigated the butyrylcholinesterase (BChE) inhibitory activity of harmane (1), naucledine (2), and dihydrodeglycocadambine (3) isolated from fractions F7 and F9 of Ochreinauclea maingayi. Both fractions demonstrated significant inhibition, exceeding 80%, against BChE at 100 µg/mL. Compound 2, is the most potent inhibitor, exhibiting an IC50 value of 22.08 µM, followed by 1 and 3 (IC50 23.96 and 30.32 µM, respectively). Docking studies revealed that 1 and 2 effectively bind to BChE, with binding energies of -51.24 and -57.17 kcal/mol, respectively. Kinetic analysis of 2 indicated mixed-mode inhibition of BChE, with a Ki of 6.08 μM. In the paralysis assay, 1 showed a weak delay in paralysis and reduced the paralysis ratio from 72.59 ± 4.7% to 60.00 ± 7.0% (12.59% reduction) followed by 2 with 70.00 ± 1.7% (2.59% reduction) compared with negative standard (DMSO 0.1%) on human amyloid β-protein in a transgenic Caenorhabditis elegans (CL4176) model.
  14. Sukumaran SY, Herrscher C, Rasol NE, Othman MA, Liew SY, Ismail NH, et al.
    J Nat Prod, 2024 Aug 23;87(8):1941-1951.
    PMID: 39028935 DOI: 10.1021/acs.jnatprod.4c00342
    In the search of new inhibitors for human coronavirus (HCoV), we screened extracts of endemic Annonaceae plants on an assay using a cellular model of Huh-7 cells infected with the human alphacoronavirus HCoV-229E. The EtOAc bark extract of the rare Southeast Asian plant Neo-uvaria foetida exhibited inhibition of HCoV-229E and SARS-CoV-2 viruses with IC50 values of 3.8 and 7.8 μg/mL, respectively. Using LC-MS/MS and molecular networking analysis guided isolation, we discovered two new labdane-type diterpenoids, 8-epi-acuminolide (1) and foetidalabdane A (4), and three known labdane diterpenoids, acuminolide (2), 17-O-acetylacuminolide (3), and spiroacuminolide (5). A new norlabdane diterpene, 16-foetinorlabdoic acid (6), was also isolated and identified. Excluding compounds 5 and 6, all other metabolites were active against the virus HCoV-229E. Terpenoids 1 and 4 presented antiviral activity against SARS-CoV-2 with IC50 values of 63.3 and 93.5 μM, respectively, indicating lower potency. Additionally, virological assays demonstrated that compounds 1, 2, and 3 exert antiviral effects against Zika virus by specifically interfering with the late stage of its infectious cycle with IC50 values of 76.0, 31.9, and 14.9 μM, respectively.
Related Terms
Filters
Contact Us

Please provide feedback to Administrator ([email protected])

External Links