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  1. Fulltext Granuloma formation and loss of tooth vitality following the use of bone wax in third molar surgery: rep ort of a case
    Raman, Rajeswary, Yap, Hsiao Fern
    Archives of Orofacial Sciences, 2014;9(1):1-3.
    MyJurnal
    In the present case, granuloma formation and loss of tooth vitality following the use of bone wax in third molar surgery in a 16 - year- old male patient were reported. Endodontic and surgical treatments were carried out on the patient. As foreign body granulomatous reaction to bone wax is not uncommon in the literature review, alternative haemostatic agents should be taken into consideration to avoid any potential complications and untoward effects of using bone wax for haemorrhage control in surgical procedures.
    Matched MeSH terms: Palmitates
  2. Studies on the kinetics of Isopropyl Palmitate synthesis in packed bed bioreactor using immobilized lipase
    Kee CY, Hassan M, Ramachandran KB
    Artif Cells Blood Substit Immobil Biotechnol, 1999 Sep-Nov;27(5-6):393-8.
    PMID: 10595438
    The objective of this research was to study the kinetics of synthesis of a commercially important ester - Isopropyl Palmitate (IPP) using immobilized lipase (Lipozyme IM). It was studied in a packed bed differential reactor. In order to establish the kinetics of the reaction, parameters such as linear velocity of the fluid through the reactor, particle size, substrate concentration, substrate molar ratio, temperature and water activity were studied. Operational and storage stability of the enzyme were also assessed. The reaction followed Michaelis-Menton kinetics as observed from the relationship of initial rate of the reaction as a function of substrate concentration. It was found that the optimum substrate concentration was 0.15M palmitic acid and isopropyl alcohol in 1:1 stoichiometric ratio. Inhibition by excess of isopropyl alcohol has been identified. The optimum temperature for the esterification reaction was found to be around 50 degrees C. The activation energy of this process was determined to be 43.67 kJ/mol. The optimum water content was 0.50%. The reaction rates were measured in the absence of any significant external diffusional limitations. Since internal diffusional limitations could not be eliminated, the kinetics observed is only apparent.
    Matched MeSH terms: Palmitates/chemical synthesis*; Palmitates/economics
  3. A new cyclopentylidene and other chemical constituents from Malaysian crotalaria pallida
    Choo YM
    Sains Malaysiana, 2017;46:1581-1586.
    Crotalaria pallida Aiton is an herbaceous legume from the family Fabaceae. In the present study, one new cyclopentyliene, crotolidene (1) and seven known compounds, i.e. hydroxydihydrobovolide (2), octacosane (3), trans-phytyl palmitate (4), linoleic acid (5), methyl oleate (6), ethyl palmitate (7), and palmitic acid (8) were isolated from the C. pallida collected from Perak, Malaysia. These compounds were isolated and characterized using extensive chromatographic and spectroscopic methods.
    Matched MeSH terms: Palmitates
  4. Effect of visible light on catalytic hydrolysis of p-nitrophenyl palmitate by the Pseudomonas cepacia lipase immobilized on sol-gel support
    Ganasen P, Khan MR, Kalam MA, Mahmud MS
    Bioprocess Biosyst Eng, 2014 Nov;37(11):2353-9.
    PMID: 24879090 DOI: 10.1007/s00449-014-1213-6
    This paper demonstrates Pseudomonas cepacia lipase catalyzed hydrolysis of p-nitrophenyl palmitate under irradiation of light with wavelengths of 250-750 nm. The reaction follows Michaelis-Menten Kinetics and the light irradiation increases the overall rate of hydrolysis. Using Lineweaver-Burk plot K M and V max values for the reaction in presence of light are found to be 39.07 and 66.67 mM/min/g, respectively; while for the same reaction under dark condition, the values are 7.08 and 10.21 mM/min/g. The linear form of enzyme dependent rate of reaction confirms that no mass-transfer limitations are present and the reaction is a kinetically controlled enzymatic reaction.
    Matched MeSH terms: Palmitates/metabolism*
  5. Fulltext Effects of selected polysorbate and sucrose ester emulsifiers on the physicochemical properties of astaxanthin nanodispersions
    Anarjan N, Tan CP
    Molecules, 2013 Jan 09;18(1):768-77.
    PMID: 23303336 DOI: 10.3390/molecules18010768
    The effects of selected nonionic emulsifiers on the physicochemical characteristics of astaxanthin nanodispersions produced by an emulsification/evaporation technique were studied. The emulsifiers used were polysorbates (Polysorbate 20, Polysorbate 40, Polysorbate 60 and Polysorbate 80) and sucrose esters of fatty acids (sucrose laurate, palmitate, stearate and oleate). The mean particle diameters of the nanodispersions ranged from 70 nm to 150 nm, depending on the emulsifier used. In the prepared nanodispersions, the astaxanthin particle diameter decreased with increasing emulsifier hydrophilicity and decreasing carbon number of the fatty acid in the emulsifier structure. Astaxanthin nanodispersions with the smallest particle diameters were produced with Polysorbate 20 and sucrose laurate among the polysorbates and the sucrose esters, respectively. We also found that the Polysorbate 80- and sucrose oleate-stabilized nanodispersions had the highest astaxanthin losses (i.e., the lowest astaxanthin contents in the final products) among the nanodispersions. This work demonstrated the importance of emulsifier type in determining the physicochemical characteristics of astaxanthin nano-dispersions.
    Matched MeSH terms: Palmitates/chemistry
  6. Fulltext Kaempferol ameliorates palmitate-induced lipid accumulation in HepG2 cells through activation of the Nrf2 signaling pathway
    Zhao L, Yang L, Ahmad K
    Hum Exp Toxicol, 2023;42:9603271221146780.
    PMID: 36607234 DOI: 10.1177/09603271221146780
    OBJECTIVES: Kaempferol (KMF), has beneficial effects against hepatic lipid accumulation. In this study, we aimed to investigate molecular mechanism underlying the protective effect of KMF on lipid accumulation.

    METHODS: HepG2 cells were treated with different concentrations of KMF and 0.5 mM palmitate (PA) for 24  h. The mRNA and protein levels of genes involved in lipid metabolism were evaluated using real-time PCR and western blot. The expression of Nrf2 was silenced using siRNA.

    RESULTS: Data indicated that KMF (20 μM) reversed PA-induced increased triglyceride (TG) levels and total lipid content. These effects were accompanied by down-regulation of the mRNA and protein levels of lipogenic genes (FAS, ACC and SREBP1), and up-regulation of genes related to fatty acid oxidation (CPT-1, HADHα and PPARα). Kaempferol significantly decreased the levels of the oxidative stress markers (ROS and MDA) and enhanced the activities of antioxidant enzymes SOD and GPx in PA-challenged cells. Luciferase analysis showed that KMF increased the transactivation of Nrf2 in hepatocytes. The results also revealed that KMF-mediated activation of Nrf2 target genes was suppressed by Nrf2 siRNA. Furthermore, Nrf2 siRNA abolished the KMF-induced reduction in ROS and MDA levels in PA treated cells. In addition, the inhibitory effect of KMF on TG levels and the mRNA and protein levels of FAS, ACC and SREPB-1 were significantly abolished by Nrf2 inhibition. Nrf2 inhibition also suppressed the KMF-induced activation of genes involved in β oxidation (CPT-1 and PPAR-α).

    CONCLUSION: The results suggest that KMF protects HepG2 cells from PA-induced lipid accumulation via activation of the Nrf2 signaling pathway.

    Matched MeSH terms: Palmitates/toxicity
  7. Fulltext Molecular dynamics simulation of palmitate ester self-assembly with diclofenac
    Abedi Karjiban R, Basri M, Abdul Rahman MB, Salleh AB
    Int J Mol Sci, 2012;13(8):9572-9583.
    PMID: 22949816 DOI: 10.3390/ijms13089572
    Palm oil-based esters (POEs) are unsaturated and non-ionic esters with a great potential to act as chemical penetration enhancers and drug carriers for transdermal drug nano-delivery. A ratio of palmitate ester and nonionic Tween80 with and without diclofenac acid was chosen from an experimentally determined phase diagram. Molecular dynamics simulations were performed for selected compositions over a period of 15 ns. Both micelles showed a prolate-like shape, while adding the drug produced a more compact micellar structure. Our results proposed that the drug could behave as a co-surfactant in our simulated model.
    Matched MeSH terms: Palmitates/chemistry*
  8. Fulltext The effect and action mechanism of resveratrol on the vascular endothelial cell by high glucose treatment
    Liu X, Tian J, Bai Q, Ashraf MA, Sarfraz M, Zhao B
    Saudi J Biol Sci, 2016 Jan;23(1):S16-21.
    PMID: 26858561 DOI: 10.1016/j.sjbs.2015.06.021
    To investigate the effect and action mechanism of resveratrol on the vascular endothelial cell by high glucose treatment. Primarily cultured human umbilical vein endothelial cells (HUVECs) were pretreated by resveratrol (0.2 μmol/L) and holding for 6 h, and then cultured in Dulbecco Modified Eagle Medium (DMEM) within 0.45 mmol/L of palmimte acid and 32.8 mmol/L of glucose, which is holding for 12 h. The cells were collected to analyze the expression of E-selected element. Supernatant of cultured cells, induced by 100 nmol/L insulin for 30 min, was used to analyze the nitric oxide content. Compared with normal control cells, the secretion of nitric oxide is stimulated by insulin decrease, however, the expression of E-selected element increased in HUVEC. Resveratrol treatment increased the secretion of nitric oxide stimulated by insulin and decreased the expression of E-selected element and partly counteracts the impairment of high glucose and palmitate acid on the function of endothelial cells. Resveratrol can improve and protect the function of high glucose and fatty acid cultured endothelial cell, and therefore may be a promising medicine in the prevention or therapy of diabetic macrovascular diseases.
    Matched MeSH terms: Palmitates
  9. Fulltext Characterization of a gas-purge method to access 11C-carbondioxide radioactivity in blood
    Ng, Yen, Green Mark, A.
    Jurnal Sains Nuklear Malaysia, 2014;26(2):14-16.
    MyJurnal
    Carbon-11 labeled radiotracers, such as 11C-acetate and
    11C-palmitate are widely used in positron
    emission tomography (PET) for noninvasive evaluation of myocardial metabolism under varied
    physiological conditions.These tracers are attractive probes of tissue physiology, because they are
    simply radiolabled versions of the native biochemical substrates. One of the major metabolites
    generated by these tracers upon the administration is 11CO2 produced via the citric acid cycle. In
    quantitative modeling of
    11C-acetate and
    11C-palmitate PET data, the fraction of blood
    11C
    radioactivity present as
    11CO2 needs to be measured to obtain a correct radiotracer arterial
    input function. Accordingly, the literature describes a method whereby the total blood
    11C-activity
    is counted in blood samples treated with base solution, while the fraction of
    1 1CO2 is measured
    after the blood is treated with acid followed by a 10 minutes gas-purge. However, a detailed
    description of the experimental validation of this method was not provided. The goal of this study
    was to test the reliability of a 10 minute gas purging method used to assay
    11CO2 radioactivity in
    blood
    Matched MeSH terms: Palmitates
  10. Improvement of mitochondrial function by celastrol in palmitate-treated C2C12 myotubes via activation of PI3K-Akt signaling pathway
    Abu Bakar MH, Tan JS
    Biomed Pharmacother, 2017 Sep;93:903-912.
    PMID: 28715871 DOI: 10.1016/j.biopha.2017.07.021
    Compelling evidences posited that high level of saturated fatty acid gives rise to mitochondrial dysfunction and inflammation in the development of insulin resistance in skeletal muscle. Celastrol is a pentacyclic triterpenoid derived from the root extracts of Tripterygium wilfordii that possesses potent anti-inflammatory properties in a number of animal models with metabolic diseases. However, the cellular mechanistic action of celastrol in alleviating obesity-induced insulin resistance in skeletal muscle remains largely unknown. Therefore, the present investigation evaluated the attributive properties of celastrol at different concentrations (10, 20, 30 and 40nM) on insulin resistance in C2C12 myotubes evoked by palmitate. We demonstrated that celastrol improved mitochondrial functions through significant enhancement of intracellular ATP content, mitochondrial membrane potential, citrate synthase activity and decrease of mitochondrial superoxide productions. Meanwhile, augmented mitochondrial DNA (mtDNA) content with suppressed DNA oxidative damage were observed following celastrol treatment. Celastrol significantly enhanced fatty acid oxidation rate and increased the level of tricarboxylic acid (TCA) cycle intermediates in palmitate-treated cells. Further analysis revealed that the improvement of glucose uptake activity in palmitate-loaded myotubes was partly mediated by celastrol via activation of PI3K-Akt insulin signaling pathway. Collectively, these findings provided evidence for the first time that the protection from palmitate-mediated insulin resistance in C2C12 myotubes by celastrol is likely associated with the improvement of mitochondrial functions-related metabolic activities.
    Matched MeSH terms: Palmitates/toxicity*
  11. Fulltext Can bone wax cause cholesterol granuloma in the petrous apex? A case report
    Wong EHC, Lim CC, Ong CA, Narayanan P
    Int J Surg Case Rep, 2020;72:587-589.
    PMID: 32698294 DOI: 10.1016/j.ijscr.2020.06.086
    BACKGROUND: Cholesterol granuloma (CG) is a rare entity but is the commonest lesion in the petrous apex. They are associated with chronic ear disease and previous temporal bone surgery. While bone wax has been known to cause foreign body reaction due to its non-resorbable property in the mastoid, it has not been documented to cause CG formation.

    CASE PRESENTATION: We described a 43 years old male who presented with a right mastoid swelling, nine years after a right retro-sigmoid craniotomy and excision for a cerebellopontine angle meningioma. He also had multiple cranial neuropathies involving trigeminal, facial and vestibulocochlear nerves. Temporal bone CT and MRI showed features suggestive of cholesterol granuloma with extensive bony erosions. He was treated with surgical excision and drainage where bone wax residues were found intraoperatively. Histopathological analysis of the lesion confirmed the diagnosis of cholesterol granuloma. Post-operatively, the mastoid swelling resolved and his recovery was uneventful.

    CONCLUSION: Our case showed that CG could manifest as a complication of bone wax usage in a neurosurgical procedure. Even though further study is needed to draw a definitive conclusion on this theory, we believe this paper will contribute to the current literature as it is the only reported case of cholesterol granuloma with bone wax as the possible causative agent. This is important so that surgeons are aware of this potential complication and use this haemostatic agent more judiciously.

    Matched MeSH terms: Palmitates
  12. Development, characterization and pharmacokinetics of mupirocin-loaded nanostructured lipid carriers (NLCs) for intravascular administration
    Alcantara KP, Zulfakar MH, Castillo AL
    Int J Pharm, 2019 Nov 25;571:118705.
    PMID: 31536765 DOI: 10.1016/j.ijpharm.2019.118705
    Mupirocin is a promising broad-spectrum antibiotic that is effective in treating MRSA infections. However, due to its rapid elimination and hydrolysis following injection and high protein binding, current therapeutic use is limited to topical administration. Nanotechnology-driven innovations provide hope for patients and practitioners in overcoming the problem of drug degradation by encapsulation. The objective of this research is to develop and characterize Mupirocin-Loaded Nanostructured Lipid Carriers (M-NLC) for intravascular administration. The MNLC was produced by a combination of high shear homogenization and high pressure homogenization of solid (cetyl palmitate) and liquid (caprylic/caprylic acid) biocompatible lipids in 5 different ratios. The mean particle size, polydispersity index (PDI) and the zeta potential (ZP) of the MNLC formulations were between 99.8 and 235 nm, PDI lower than 0.164, ZP from -25.96 to -19.53 and pH ranging from 6.28-6.49. The MNLC formulation also enhances the anti-bacterial activity of mupirocin. All formulation showed sustained drug release and good physical characteristics for three months storage under 25 °C. It also revealed that the MNLC 1 is safe at 250 mg/kg dose in rats. The MNLC 1 also showed a significant increase in plasma concentration in rabbits following IV administration thus, demonstrating an enhancement on its pharmacokinetic profile as compared to free mupirocin.
    Matched MeSH terms: Palmitates
  13. Fulltext Secondary Metabolites, Antioxidant, and Antiproliferative Activities of Dioscorea bulbifera Leaf Collected from Endau Rompin, Johor, Malaysia
    Mainasara MM, Abu Bakar MF, Md Akim A, Linatoc AC, Abu Bakar FI, Ranneh YKH
    Evid Based Complement Alternat Med, 2021;2021:8826986.
    PMID: 33505506 DOI: 10.1155/2021/8826986
    Breast cancer is among the most commonly diagnosed cancer and the leading cause of cancer-related death among women globally. Malaysia is a country that is rich in medicinal plant species. Hence, this research aims to explore the secondary metabolites, antioxidant, and antiproliferative activities of Dioscorea bulbifera leaf collected from Endau Rompin, Johor, Malaysia. Antioxidant activity was assessed using 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and 2,2'-azino-bis-3-ethylbenzthiazoline-6-sulphonic acid (ABTS) assays, while the cytotoxicity of D. bulbifera on MDA-MB-231 and MCF-7 breast cancer cell lines was tested using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cell cycle analysis and apoptosis were assessed using flow cytometry analysis. Phytochemical profiling was conducted using gas chromatography-mass spectrometry (GC-MS). Results showed that methanol extract had the highest antioxidant activity in DPPH, FRAP, and ABTS assays, followed by ethyl acetate and hexane extracts. D. bulbifera tested against MDA-MB-231 and MCF-7 cell lines showed a pronounced cytotoxic effect with IC50 values of 8.96 μg/mL, 6.88 μg/mL, and 3.27 μg/mL in MCF-7 and 14.29 μg/mL, 11.86 μg/mL, and 7.23 μg/mL in MDA-MB-231, respectively. Cell cycle analysis also indicated that D. bulbifera prompted apoptosis at various stages, and a significant decrease in viable cells was detected within 24 h and substantially improved after 48 h and 72 h of treatment. Phytochemical profiling of methanol extract revealed the presence of 39 metabolites such as acetic acid, n-hexadecanoic acid, acetin, hexadecanoate, 7-tetradecenal, phytol, octadecanoic acid, cholesterol, palmitic acid, and linolenate. Hence, these findings concluded that D. bulbifera extract has promising anticancer and natural antioxidant agents. However, further study is needed to isolate the bioactive compounds and validate the effectiveness of this extract in the In in vivo model.
    Matched MeSH terms: Palmitates
  14. Celastrol attenuates mitochondrial dysfunction and inflammation in palmitate-mediated insulin resistance in C3A hepatocytes
    Abu Bakar MH, Sarmidi MR, Tan JS, Mohamad Rosdi MN
    Eur J Pharmacol, 2017 Mar 15;799:73-83.
    PMID: 28161417 DOI: 10.1016/j.ejphar.2017.01.043
    Accumulating evidence indicates that mitochondrial dysfunction-induced inflammation is among the convergence points for the greatest hallmarks of hepatic insulin resistance. Celastrol, an anti-inflammatory compound from the root of Tripterygium Wilfordii has been reported to mitigate insulin resistance and inflammation in animal disease models. Nevertheless, the specific mechanistic actions of celastrol in modulating such improvements at the cellular level remain obscure. The present study sought to explore the mechanistic roles of celastrol upon insulin resistance induced by palmitate in C3A human hepatocytes. The hepatocytes exposed to palmitate (0.75mM) for 48h exhibited reduced both basal and insulin-stimulated glucose uptake, mitochondrial dysfunction, leading to increased mitochondrial oxidative stress with diminished fatty acid oxidation. Elevated expressions of nuclear factor-kappa B p65 (NF-κB p65), c-Jun NH(2)-terminal kinase (JNK) signaling pathways and the amplified release of pro-inflammatory cytokines including IL-8, IL-6, TNF-α and CRP were observed following palmitate treatment. Consistently, palmitate reduced and augmented phosphorylated Tyrosine-612 and Serine-307 of insulin receptor substrate-1 (IRS-1) proteins, respectively in hepatocytes. However, celastrol at the optimum concentration of 30nM was able to reverse these deleterious occasions and protected the cells from mitochondrial dysfunction and insulin resistance. Importantly, we presented evidence for the first time that celastrol efficiently prevented palmitate-induced insulin resistance in hepatocytes at least, via improved mitochondrial functions and insulin signaling pathways. In summary, the present investigation underlines a conceivable mechanism to elucidate the cytoprotective potential of celastrol in attenuating mitochondrial dysfunction and inflammation against the development of hepatic insulin resistance.
    Matched MeSH terms: Palmitates/pharmacology*
  15. Cold-adapted organic solvent tolerant alkalophilic family I.3 lipase from an Antarctic Pseudomonas
    Ganasen M, Yaacob N, Rahman RN, Leow AT, Basri M, Salleh AB, et al.
    Int J Biol Macromol, 2016 Nov;92:1266-1276.
    PMID: 27506122 DOI: 10.1016/j.ijbiomac.2016.06.095
    Lipolytic enzymes with cold adaptation are gaining increasing interest due to their biotechnological prospective. Previously, a cold adapted family I.3 lipase (AMS8 lipase) was isolated from an Antarctic Pseudomonas. AMS8 lipase was largely expressed in insoluble form. The refolded His-tagged recombinant AMS8 lipase was purified with 23.0% total recovery and purification factor of 9.7. The purified AMS8 lipase migrated as a single band with a molecular weight approximately 65kDa via electrophoresis. AMS8 lipase was highly active at 30°C at pH 10. The half-life of AMS8 lipase was reported at 4 and 2h under the incubation of 30 and 40°C, respectively. The lipase was stable over a broad range of pH. It showed enhancement effect in its relative activity under the presence of Li(+), Na(+), K(+), Rb(+) and Cs(+) after 30min treatment. Heavy metal ions such as Cu(2+), Fe(3+) and Zn(2+) inhibited AMS8 activity. This cold adapted alkalophilic AMS lipase was also active in various organic solvent of different polarity. These unique properties of this biological macromolecule will provide considerable potential for many biotechnological applications and organic synthesis at low temperature.
    Matched MeSH terms: Palmitates/chemistry*
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