Displaying publications 101 - 112 of 112 in total

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  1. Sosroseno W, Musa M, Ravichandran M, Fikri Ibrahim M, Bird PS, Seymour GJ
    Oral Microbiol. Immunol., 2006 Jun;21(3):145-50.
    PMID: 16626370
    The aim of the present study was to determine whether or not lipopolysaccharide from Actinobacillus actinomycetemcomitans could stimulate arginase activity in a murine macrophage cell line (RAW264.7 cells).
    Matched MeSH terms: Dexamethasone/pharmacology
  2. Ramli ES, Suhaimi F, Asri SF, Ahmad F, Soelaiman IN
    J. Bone Miner. Metab., 2013 May;31(3):262-73.
    PMID: 23274351 DOI: 10.1007/s00774-012-0413-x
    Rapid onset of bone loss is a frequent complication of systemic glucocorticoid therapy which may lead to fragility fractures. Glucocorticoid action in bone depends upon the activity of 11β-hydroxysteroid dehydrogenase type 1 enzyme (11β-HSD1). Regulations of 11β-HSD1 activity may protect the bone against bone loss due to excess glucocorticoids. Glycyrrhizic acid (GCA) is a potent inhibitor of 11β-HSD. Treatment with GCA led to significant reduction in bone resorption markers. In this study we determined the effect of GCA on 11β-HSD1 activity in bones of glucocorticoid-induced osteoporotic rats. Thirty-six male Sprague-Dawley rats (aged 3 months and weighing 250-300 g) were divided randomly into groups of ten. (1) G1, sham operated group; (2) G2, adrenalectomized rats administered with intramuscular dexamethasone 120 μg/kg/day and oral vehicle normal saline vehicle; and (3) G3, adrenalectomized rats administered with intramuscular dexamethasone 120 μg/kg/day and oral GCA 120 mg/kg/day The results showed that GCA reduced plasma corticosterone concentration. GCA also reduced serum concentration of the bone resorption marker, pyridinoline and induced 11β-HSD1 dehydrogenase activity in the bone. GCA improved bone structure, which contributed to stronger bone. Therefore, GCA has the potential to be used as an agent to protect the bone against glucocorticoid induced osteoporosis.
    Matched MeSH terms: Dexamethasone/adverse effects
  3. Greenwood M, Greenwood MP, Mecawi AS, Loh SY, Rodrigues JA, Paton JF, et al.
    Mol Brain, 2015 Oct 26;8(1):68.
    PMID: 26503226 DOI: 10.1186/s13041-015-0159-1
    BACKGROUND: Arginine vasopressin (AVP), a neuropeptide hormone that functions in the regulation of water homeostasis by controlling water re-absorption at kidneys, is synthesised in supraoptic nucleus and paraventricular nucleus of the hypothalamus. An increase in plasma osmolality stimulates secretion of AVP to blood circulation and induces AVP synthesis in these nuclei. Although studies on mechanism of AVP transcriptional regulation in hypothalamus proposed that cAMP and glucocorticoids positively and negatively regulate Avp expression, respectively, the molecular mechanisms have remained elusive. Recently, we identified CREB3L1 (cAMP-responsive element binding protein 3 like 1) as a putative transcription factor of Avp transcription in the rat hypothalamus. However the mechanism of how CREB3L1 is regulated in response of hyperosmotic stress in the neurons of hypothalamus has never been reported. This study aims to investigate effect of previously reported regulators (cAMP and glucocorticoid) of Avp transcription on transcription factor CREB3L1 in order to establish a molecular explanation for cAMP and glucocorticoids effect on AVP expression.

    RESULTS: The effect of cAMP and glucocorticoid treatment on Creb3l1 was investigated in both AtT20 cells and hypothalamic organotypic cultures. The expression of Creb3l1 was increased in both mRNA and protein level by treatment with forskolin, which raises intracellular cAMP levels. Activation of cAMP by forskolin also increased Avp promoter activity in AtT20 cells and this effect was blunted by shRNA mediated silencing of Creb3l1. The forskolin induced increase in Creb3l1 expression was diminished by combined treatment with dexamethasone, and, in vivo, intraperitoneal dexamethasone injection blunted the increase in Creb3l1 and Avp expression induced by hyperosmotic stress.

    CONCLUSION: Here we shows that cAMP and glucocorticoid positively and negatively regulate Creb3l1 expression in the rat hypothalamus, respectively, and regulation of cAMP on AVP expression is mediated through CREB3L1. This data provides the connection between CREB3L1, a newly identified transcription factor of AVP expression, with the previously proposed mechanism of Avp transcription which extends our understanding in transcription regulation of Avp in the hypothalamus.

    Matched MeSH terms: Dexamethasone/pharmacology
  4. Bosco I, Teh A
    Leukemia, 1995 Jun;9(6):951-4.
    PMID: 7596183
    Reports on the outcome of treatment in ALL in Asian (non-Caucasian) adults have been few, and published results compare very unfavourably with results of treatment from 'Western' centres. Seventy-four newly diagnosed Malaysian patients with ALL between the ages of 15 and 69 were treated from 1986 to 1990. The clinical features and prognostic factors were similar to those reported in 'Western' series. The chemotherapy protocol utilized was adapted from the one used by Hoelzer et al in the multicentre German study. The complete remission rate was 73%. The probability of continuous complete remission at 5 years was 29% with a median duration of remission of 15 months. This compares with Hoelzer's initial results of 77% CR rate and 35% CCR at 5 years. Patients with an initial white cell count of less than 30 x 10(9)/l at presentation were found to have a significantly better disease-free survival than those with a count of more than 30 x 10(9)/l (35 vs 22%, P = 0.026, univariate analysis). There was no difference in leukaemia-free survival according to age, sex, ethnic group, or immunophenotype. These results show that the use of moderately intensive chemotherapy protocols in Asian (non-Caucasian) patients achieves similar results to those used in Caucasians. We also showed that the difficulties in 'curing' approximately 70% of adult patient with ALL are universal.
    Matched MeSH terms: Dexamethasone/administration & dosage
  5. Razali N, Agarwal R, Agarwal P, Froemming GRA, Tripathy M, Ismail NM
    Eur J Pharmacol, 2018 Nov 05;838:1-10.
    PMID: 30171854 DOI: 10.1016/j.ejphar.2018.08.035
    Trans-resveratrol was earlier shown to lower intraocular pressure (IOP) in rats; however, its mechanisms of action remain unclear. It has been shown to modulate adenosine receptor (AR) and TGF-β2 signaling, both of which play a role in regulating IOP. Hence, we investigated effects of trans-resveratrol on AR and TGF-β2 signaling. Steroid-induced ocular hypertensive (SIOH) rats were pretreated with A1AR, phospholipase C (PLC) and ERK1/2 inhibitors and were subsequently treated with single drop of trans-resveratrol. Metalloproteinases (MMP)-2 and -9 were measured in aqueous humor (AH). In another set of experiments, effect of trans-resveratrol on AH level of tissue plasminogen activator (tPA) and urokinase plasminogen activator (uPA) was determined after single and multiple drop administration in SIOH rats. Effect of trans-resveratrol on ARs expression, PLC and pERK1/2 activation and MMPs, tPA and uPA secretion was determined using human trabecular meshwork cells (HTMC). Further, effect of trans-resveratrol on TGF-β2 receptors, SMAD signaling molecules and uPA and tPA expression by HTMC was determined in the presence and absence of TGF-β2. Pretreatment with A1AR, PLC and ERK1/2 inhibitors antagonized the IOP lowering effect of trans-resveratrol and caused significant reduction in the AH level of MMP-2 in SIOH rats. Trans-resveratrol increased A1AR and A2AAR expression, cellular PLC, pERK1/2 levels and MMP-2, tPA and uPA secretion by HTMC. Additionally, it produced TGFβRI downregulation and SMAD 7 upregulation. In conclusion, IOP lowering effect of trans-resveratrol involves upregulation of A1AR expression, PLC and ERK1/2 activation and increased MMP-2 secretion. It downregulates TGFβRI and upregulates SMAD7 hence, inhibits TGF-β2 signaling.
    Matched MeSH terms: Dexamethasone/pharmacology
  6. Chasen M, Urban L, Schnadig I, Rapoport B, Powers D, Arora S, et al.
    Support Care Cancer, 2017 01;25(1):85-92.
    PMID: 27557833
    PURPOSE: Addition of rolapitant to standard antiemetic therapy improved protection against chemotherapy-induced nausea and vomiting (CINV) in phase 3 trials of patients receiving highly emetogenic chemotherapy (HEC) or moderately emetogenic chemotherapy (MEC). Here, we assessed the impact of CINV on the daily lives of patients receiving HEC or MEC using the Functional Living Index-Emesis (FLIE).

    METHODS: In three double-blind phase 3 studies, patients receiving HEC or MEC were randomized 1:1 to receive oral rolapitant 180 mg or placebo prior to chemotherapy plus 5-hydroxytryptamine type 3 receptor antagonist and dexamethasone therapy. Patients completed the FLIE questionnaire on day 6 of cycle 1. Endpoints included FLIE total score, nausea and vomiting domain scores, and the proportion of patients with no impact on daily life (total score >108 [range 18-126]). We performed a prespecified analysis of the MEC/anthracycline-cyclophosphamide (AC) study and a post hoc analysis of two pooled cisplatin-based HEC studies.

    RESULTS: In the pooled HEC studies, rolapitant significantly improved the FLIE total score (114.5 vs 109.3, p 

    Matched MeSH terms: Dexamethasone/therapeutic use
  7. Attiq A, Jalil J, Husain K, Mohamad HF, Ahmad A
    J Ethnopharmacol, 2021 Jul 15;275:114120.
    PMID: 33857595 DOI: 10.1016/j.jep.2021.114120
    ETHNOPHARMACOLOGICAL RELEVANCE: Numerous Alphonsea species including Alphonsea elliptica (mempisang) leaves and fruits are indigenously used in inflammatory conditions such as postpartum swelling and rheumatism in southeast Asian countries. In our previous in-vitro findings, A. elliptica methanol extract exhibited platelet-activating factor inhibition, suggesting the presence of phyto-constituents with anti-inflammatory potential.

    AIM OF THE STUDY: However, so far there is no literature available on the anti-inflammatory activity of this species. Henceforth, based on the above background and our previous laboratory findings, we hypothesize that phytoconstituents of A. elliptica could possess anti-inflammatory potential against inflammatory mediators including prostaglandin-E2 (PGE2), cyclooxegenase-2 (COX-2) and cytokines (IL-1β and IL-6).

    MATERIALS AND METHODS: Vacuum and column chromatography techniques were employed for the isolation of phytoconstituents. The structure elucidation was carried out using HRESI-MS, 1H and 13C-NMR analysis and compared with the published literature. For cytotoxicity analysis, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay was performed on peripheral blood mononuclear cells. In-vitro anti-inflammatory activities were evaluated against the levels of PGE2, COX-2, IL-1β and IL-6 in lipopolysaccharide (LPS)-induced human plasma using enzyme-linked immunosorbent assay and radioimmunoassay.

    RESULTS: Unprecedentedly, chromatographic purification of methanolic leaves extract afforded five flavones namely vitexin, isovitexin, orientin, isoorientin, schaftoside with three flavanols; kaempferol, myricetin and rutin from A elliptica. In cell viability analysis, isolates did not present cytotoxicity up to 50 μM. In anti-inflammatory evaluation, orientin and isoorientin exhibited strong (≥70%), while isovitexin and vitexin produced strong to moderate (50-69%) PGE2, COX-2, IL-1β and IL-6 inhibition at 25 and 50 μM. Isoorientin, orientin, isovitexin, and vitexin showed significant (p 

    Matched MeSH terms: Dexamethasone
  8. Diymitra, K. G., Mushawiahti, M., Aida Zairani, M. Z.
    MyJurnal
    Orbital cellulitis is a relatively common disease affecting predominantly the paediatric population. Most cases occur as a result of spread from the nearby sinuses. Other causes include penetrating trauma or extension from infected adjacent structures.If left untreated, this condition may result in devastating sequelae such as orbital apex syndrome, cavernous sinus thrombosis, meningitis, cranial nerve palsies, intracranial abscess formation and even death. A 47 year old immunocompetent Burmese lady presented with left eyelid swelling of 2 days duration associated with eye redness, blurring of vision and diplopia. Previously, there was history of right maxillary sinusitis and parapharyngeal abscess 9 months prior to presentation. On examination, she was afebrile with vision of 1/60 for the left eye with positiverelative afferent pupillary defect (RAPD). The eye was proptosed and swollen with restricted extraocular movements in all gazes. Conjunctiva was injected with chemosis and there was corneal epithelial bedewing. Otherwise anterior chamber was quiet and intraocular pressure was 51mmHg. Bilateral fundus examination was normal. Computed tomography (CT) scan of the orbit and paranasal sinus showed dense sinusitis and periosteal abscess at the lateral orbital wall.She was started on intravenous (IV) Cefuroxime and Metronidazole and underwent Functional Endoscopic Sinus Surgery (FESS) and orbital decompression. Intra-operatively there was pus and debris at the left anterior ethmoid, maxillary and sphenoid air sinuses and cultures revealed Klebsiella pneumoniae which was sensitive to Cefuroxime. Despite medical and surgical treatment, left orbital swelling only reduced minimally. However after starting intravenous Dexamethasone the swelling dramatically improved. She completed 10 days of intravenous Dexamethasone. Upon discharge, she was given oral Dexamethasone 2mg daily for 2 weeks and completed 2 weeks of oral Cefuroxime and Metronidazole. Intraocular pressure normalised and vision recovered to 6/9. A repeat CT orbit 3 weeks later showed resolving preseptal and periorbital collection.
    Matched MeSH terms: Dexamethasone
  9. Maharani ND, Fuadi A, Halimi RA
    Med J Malaysia, 2023 Nov;78(6):808-814.
    PMID: 38031225
    INTRODUCTION: Craniotomy tumour is brain surgery that can induce a stress response. The stress response can be measured using haemodynamic parameters and plasma cortisol concentration. The stress response that occurs can affect an increase in sympathetic response, such as blood pressure and heart rate, which can lead to an increase in intracranial pressure. Scalp block can reduce the stress response to surgery and post-operative craniotomy tumour pain. The local anaesthetic drug bupivacaine 0.25% is effective in reducing post-operative pain and stress in the form of reducing plasma cortisol levels. The adjuvant addition of clonidine 2 μg/kg or dexamethasone may be beneficial.

    MATERIALS AND METHODS: A randomised control clinical trial was conducted at the Central Surgery Installation and Hasan Sadikin General Hospital Bandung and Dr. Mohammad Husein Hospital Palembang from December 2022 to June 2023. A total of 40 participants were divided into two groups using block randomisation. Group I receives bupivacaine 0.25% and clonidine 2 μg/kg, and group II receives bupivacaine 0.25% and dexamethasone 8 mg. The plasma cortisol levels of the patient will be assessed at (T0, T1 and T2). All the patient were intubated under general anesthaesia and received the drug for scalp block based on the group being randomised. Haemodynamic monitoring was carried out.

    RESULTS: There was a significant difference in administering bupivacaine 0.25% and clonidine 2μg/kg compared to administering bupivacaine 0.25% and dexamethasone 8 mg/kg as analgesia for scalp block in tumour craniotomy patients on cortisol levels at 12 hours post-operatively (T1) (p=0.048) and 24 hours post-surgery (T2) (p=0.027), while post-intubation cortisol levels (T0) found no significant difference (p=0.756). There is a significant difference in Numeric Rating Scale (NRS) at post-intubation (T0) (p=0.003), 12 hours post-operatively (T1) (p=0.002) and 24 hours post-surgery (T2) (p=0.004), There were no postprocedure scalp block side effects in both groups.

    CONCLUSION: The study found that scalp block with 0.25% bupivacaine and 2μg/kg clonidine is more effective in reducing NRS scores and cortisol levels compared bupivacaine 0.25% and dexamethasone 8mg in tumour craniotomy patients.

    Matched MeSH terms: Dexamethasone
  10. Ima-Nirwana S, Suhaniza S
    J Med Food, 2004;7(1):45-51.
    PMID: 15117552
    Long-term glucocorticoid treatment is associated with severe side effects, such as obesity and osteoporosis. A palm oil-derived vitamin E mixture had been shown previously to be protective against osteoporosis in rats given 120 microg/kg dexamethasone daily for 12 weeks. In this study we determined the effects of two isomers of vitamin E (i.e., palm oil-derived gamma-tocotrienol and the commercially available alpha-tocopherol, 60 mg/kg of body weight/day) on body composition and bone calcium content in adrenalectomized rats replaced with two doses of dexamethasone, 120 microg/kg and 240 microg/kg daily. Treatment period was 8 weeks. gamma-Tocotrienol (60 mg/kg of body weight/day) was found to reduce body fat mass and increase the fourth lumbar vertebra bone calcium content in these rats, while alpha-tocopherol (60 mg/kg of body weight/day) was ineffective. Therefore, in conclusion, palm oil-derived gamma-tocotrienol has the potential to be utilized as a prophylactic agent in prevention of the side effects of long-term glucocorticoid use.
    Matched MeSH terms: Dexamethasone
  11. Greenwood MP, Greenwood M, Mecawi AS, Antunes-Rodrigues J, Paton JF, Murphy D
    Mol Brain, 2016 Jan 07;9:1.
    PMID: 26739966 DOI: 10.1186/s13041-015-0182-2
    BACKGROUND: Rasd1 is a member of the Ras family of monomeric G proteins that was first identified as a dexamethasone inducible gene in the pituitary corticotroph cell line AtT20. Using microarrays we previously identified increased Rasd1 mRNA expression in the rat supraoptic nucleus (SON) and paraventricular nucleus (PVN) of the hypothalamus in response to increased plasma osmolality provoked by fluid deprivation and salt loading. RASD1 has been shown to inhibit adenylyl cyclase activity in vitro resulting in the inhibition of the cAMP-PKA-CREB signaling pathway. Therefore, we tested the hypothesis that RASD1 may inhibit cAMP stimulated gene expression in the brain.

    RESULTS: We show that Rasd1 is expressed in vasopressin neurons of the PVN and SON, within which mRNA levels are induced by hyperosmotic cues. Dexamethasone treatment of AtT20 cells decreased forskolin stimulation of c-Fos, Nr4a1 and phosphorylated CREB expression, effects that were mimicked by overexpression of Rasd1, and inhibited by knockdown of Rasd1. These effects were dependent upon isoprenylation, as both farnesyltransferase inhibitor FTI-277 and CAAX box deletion prevented Rasd1 inhibition of cAMP-induced gene expression. Injection of lentiviral vector into rat SON expressing Rasd1 diminished, whereas CAAX mutant increased, cAMP inducible genes in response to osmotic stress.

    CONCLUSIONS: We have identified two mechanisms of Rasd1 induction in the hypothalamus, one by elevated glucocorticoids in response to stress, and one in response to increased plasma osmolality resulting from osmotic stress. We propose that the abundance of RASD1 in vasopressin expressing neurons, based on its inhibitory actions on CREB phosphorylation, is an important mechanism for controlling the transcriptional responses to stressors in both the PVN and SON. These effects likely occur through modulation of cAMP-PKA-CREB signaling pathway in the brain.

    Matched MeSH terms: Dexamethasone/pharmacology
  12. Qattan MY, Bakker EY, Rajendran R, Chen DW, Saha V, Liu J, et al.
    PLoS One, 2017;12(6):e0178606.
    PMID: 28582465 DOI: 10.1371/journal.pone.0178606
    Glucocorticoids (GCs) and topoisomerase II inhibitors are used to treat acute lymphoblastic leukaemia (ALL) as they induce death in lymphoid cells through the glucocorticoid receptor (GR) and p53 respectively. Mechanisms underlying ALL cell death and the contribution of the bone marrow microenvironment to drug response/resistance remain unclear. The role of the microenvironment and the identification of chemoresistance determinants were studied by transcriptomic analysis in ALL cells treated with Dexamethasone (Dex), and Etoposide (Etop) grown in the presence or absence of bone marrow conditioned media (CM). The necroptotic (RIPK1) and the apoptotic (caspase-8/3) markers were downregulated by CM, whereas the inhibitory effects of chemotherapy on the autophagy marker Beclin-1 (BECN1) were reduced suggesting CM exerts cytoprotective effects. GCs upregulated the RIPK1 ubiquitinating factor BIRC3 (cIAP2), in GC-sensitive (CEM-C7-14) but not in resistant (CEM-C1-15) cells. In addition, CM selectively affected GR phosphorylation in a site and cell-specific manner. GR is recruited to RIPK1, BECN1 and BIRC3 promoters in the sensitive but not in the resistant cells with phosphorylated GR forms being generally less recruited in the presence of hormone. FACS analysis and caspase-8 assays demonstrated that CM promoted a pro-survival trend. High molecular weight proteins reacting with the RIPK1 antibody were modified upon incubation with the BIRC3 inhibitor AT406 in CEM-C7-14 cells suggesting that they represent ubiquitinated forms of RIPK1. Our data suggest that there is a correlation between microenvironment-induced ALL proliferation and altered response to chemotherapy.
    Matched MeSH terms: Dexamethasone/pharmacology
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