Displaying publications 1 - 20 of 831 in total

  1. Hassani A, Hussain SA, Abdullah N, Kamarudin S, Rosli R
    AAPS PharmSciTech, 2019 Jan 07;20(2):53.
    PMID: 30617521 DOI: 10.1208/s12249-018-1238-2
    Orotic acid (OA) nanoparticles were prepared using the freeze-drying method. The antihypertensive activity and antioxidant capacity of OA and orotic acid-loaded gum arabic nanoparticles (OAGANPs) were examined using the angiotensin-converting enzyme (ACE), 1,1-diphenyl-2-picrylhydrazyl (DPPH), nitric oxide (NO), and β-carotene assays, as well as the quantification of total phenolic content (TPC). The DPPH and NO scavenging activities of OAGANPs were significantly higher than those of the OA solution. The β-carotene bleaching assay of OAGANPs showed a dose-dependent trend, while 500 μg/ml was significantly more effective than the other concentrations, which exerted 63.4% of the antioxidant activity. The in vitro antihypertensive assay revealed that the OAGANPs exhibited the most potent ACE inhibition activity, when compared to the OA solution. Hence, results revealed the potential of preparing the OA as a nanoparticle formulation in enhancing the antioxidant and antihypertensive properties compared to the OA solution.
    Matched MeSH terms: Dose-Response Relationship, Drug
  2. Rajendran K, Anwar A, Khan NA, Siddiqui R
    ACS Chem Neurosci, 2017 12 20;8(12):2626-2630.
    PMID: 29206032 DOI: 10.1021/acschemneuro.7b00430
    The overall aim of this study was to determine whether conjugation with silver nanoparticles enhances effects of available drugs against primary amoebic meningoencephalitis due to Naegleria fowleri. Amphotericin B, Nystatin, and Fluconazole were conjugated with silver nanoparticles, and synthesis was confirmed using UV-visible spectrophotometry. Atomic force microscopy determined their size in range of 20-100 nm. To determine amoebicidal effects, N. fowleri were incubated with drugs-conjugated silver nanoparticles, silver nanoparticles alone, and drugs alone. The findings revealed that silver nanoparticles conjugation significantly enhanced antiamoebic effects of Nystatin and Amphotericin B but not Fluconazole at micromolar concentrations, compared with the drugs alone. For the first time, our findings showed that silver nanoparticle conjugation enhances efficacy of antiamoebic drugs against N. fowleri. Given the rarity of the disease and challenges in developing new drugs, it is hoped that modifying existing drugs to enhance their antiamoebic effects is a useful avenue that holds promise in improving the treatment of brain-eating amoebae infection due to N. fowleri.
    Matched MeSH terms: Dose-Response Relationship, Drug
  3. AIDS Patient Care STDS, 2000 Apr;14(4):225-6.
    PMID: 10806645
    Matched MeSH terms: Dose-Response Relationship, Drug
  4. Wei LS, Wee W, Siong JY, Syamsumir DF
    Acta Med Iran, 2011;49(10):670-4.
    PMID: 22071643
    Peperomia pellucida leaf extract was characterized for its anticancer, antimicrobial, antioxidant activities, and chemical compositions. Anticancer activity of P. pellucida leaf extract was determined through Colorimetric MTT (tetrazolium) assay against human breast adenocarcinoma (MCF-7) cell line and the antimicrobial property of the plant extract was revealed by using two-fold broth micro-dilution method against 10 bacterial isolates. Antioxidant activity of the plant extract was then characterized using α, α-diphenyl-β-picrylhydrazyl (DPPH) radical scavenging method and the chemical compositions were screened and identified using gas chromatography-mass spectrometry (GC-MS). The results of present study indicated that P. pellucida leaf extract possessed anticancer activities with half maximal inhibitory concentration (IC(50)) of 10.4 ± 0.06 µg/ml. The minimum inhibitory concentration (MIC) values were ranged from 31.25 to 125 mg/l in which the plant extract was found to inhibit the growth of Edwardsiella tarda, Escherichia coli, Flavobacterium sp., Pseudomonas aeruginosa and Vibrio cholerae at 31.25 mg/l; Klebsiella sp., Aeromonas hydrophila and Vibrio alginolyticus at 62.5 mg/l; and it was able to control the growth of Salmonella sp. and Vibrio parahaemolyticus at 125 mg/l. At the concentration of 0.625 ppt, the plant extract was found to inhibit 30% of DPPH, free radical. Phytol (37.88%) was the major compound in the plant extract followed by 2-Naphthalenol, decahydro- (26.20%), Hexadecanoic acid, methyl ester (18.31%) and 9,12-Octadecadienoic acid (Z,Z)-, methyl ester (17.61%). Findings from this study indicated that methanol extract of P. pellucida leaf possessed vast potential as medicinal drug especially in breast cancer treatment.
    Matched MeSH terms: Dose-Response Relationship, Drug
  5. Gill JS, Pillai SK, Koh OH, Jambunathan ST
    Acta Neurol Belg, 2011 Jun;111(2):155-6.
    PMID: 21748939
    Somnambulism or sleepwalking is a sleep disorder of arousal. Compared to in adults, pediatric and adolescent sleep disorders is still under-researched and poorly described. We report the successful use of low dose quietiapine, an atypical antipsychotic, in the treatment of a 15-year-old Indian male who presented with significant somnambulism. To the best of our knowledge, this is the first report on the use of quetiapine for the treatment of somnambulism in the literature. The presence of high voltage delta waves in sleepwalkers has been offered as a possible explanation for the patho-physiology of sleepwalking Quetiapine has been reported to decrease brain delta activity, and we postulate that this may be the mechanism on how it was beneficial for our patient.
    Matched MeSH terms: Dose-Response Relationship, Drug
  6. Suhaimi FW, Yusoff NH, Dewa A, Yusof AP
    Acta Neurol Belg, 2010 Mar;110(1):57-64.
    PMID: 20514927
    Obesity is intimately associated with hypertension; increases in blood pressure are closely related to the magnitude of weight gain. The present study aims to determine whether the excitatory amino acid input to rostral ventrolateral medulla (RVLM) contributes to elevated blood pressure in rats with diet-induced obesity. Male Sprague-Dawley rats weighing 280 to 300 grams were fed with a low-fat diet (10% kcal from fat) or moderately high-fat diet (32% kcal from fat) for 16 weeks. At week 16, rats on the moderate high-fat diet were segregated into obesity-prone and obesity-resistant rats based on body weight distribution. Baseline mean arterial pressure (MAP) was significantly higher in obesity-prone rats as compared to obesity-resistant and rats on a low-fat diet. Bilateral injection of kynurenic acid (KYN) (40 nM) into the RVLM of the obesity-prone rats reduced MAP to levels significantly different from those observed in rats on a low-fat diet and obesity-resistant rats (no change in MAP). At a lower concentration (4 nM), KYN injection did not produce any change in MAP in any group. The results obtained suggest that excitatory amino acid input to the RVLM does contribute to the development of hypertension in rats with diet-induced obesity.
    Matched MeSH terms: Dose-Response Relationship, Drug
  7. Armenia A, Sattar MA, Abdullah NA, Khan MA, Johns EJ
    Acta Pharmacol Sin, 2008 May;29(5):564-72.
    PMID: 18430364 DOI: 10.1111/j.1745-7254.2008.00788.x
    This study investigates the subtypes of the alpha1-adrenoceptor mediating the adrenergically-induced renal vasoconstrictor responses in streptozotocin-induced diabetic and non-diabetic 2-kidney one clip (2K1C) Goldblatt hypertensive rats.
    Matched MeSH terms: Dose-Response Relationship, Drug
  8. Chazova IE, Dongre N, Vigdorchik AV
    Adv Ther, 2011 Feb;28(2):134-49.
    PMID: 21240661 DOI: 10.1007/s12325-010-0099-1
    The aim of our study was to evaluate the safety and effectiveness of the free combination of amlodipine/valsartan in patients with arterial hypertension in a real-life setting.
    Matched MeSH terms: Dose-Response Relationship, Drug
  9. Selvaratnam G, Philips RH, Mohamed AK
    Adverse Drug React Toxicol Rev, 1999 Jun;18(2):61-105.
    PMID: 10478286
    Matched MeSH terms: Dose-Response Relationship, Drug
  10. Vijayapandi P, Annabathina V, SivaNagaSrikanth B, Manjunath V, Boggavarapu P, Mohammed P AK, et al.
    PMID: 24082330
    The present investigation was aimed at determining the effects of hexane, acetone, methanol and aqueous extracts of Acorus calamus leaves (ACHE, ACAE, ACME and ACAQE) on cholinergic and histaminic system using isolated frog rectus abdominis muscle and guinea pig ileum. A dose dependent potentiation of Ach response (anticholinesterase like effect) was found with ACAE and ACME at 0.25, 0.5, 0.75 and 1 mg/ml, but at higher dose of ACAE, ACME, ACAQE and ACHE (5, 20 mg/ml) inhibit the Ach response (antinicotinic effect). These results revealed biphasic effect of Acorus calamus leaves extracts on acetylcholine induced contractile response in isolated frog rectus abdominis muscle preparation (i.e. potentiation effect at lower dose and inhibitory effect at higher dose). Studies on isolated guinea pig ileum demonstrated antihistaminic effect in a dose dependent manner (100-1000 µg/ml) with ACAE, ACME and ACAQE. In addition, the dose dependent inhibition of Ach response (antimuscarinic effect) was observed with ACAE and ACME. In conclusion, Acorus calamus leaves extracts exerts antinicotinic, anticholinesterase like activities in isolated frog rectus abdominis muscle and antihistaminic, antimuscarinic effect in guinea pig ileum. It has been suggested that these observed activities can be further studied for therapeutic potential of Acorus calamus leaves in the treatment of cognitive disorders and asthma.
    Matched MeSH terms: Dose-Response Relationship, Drug
  11. Makpol S, Yaacob N, Zainuddin A, Yusof YA, Ngah WZ
    Afr J Tradit Complement Altern Med, 2009 Jul 03;6(4):560-72.
    PMID: 20606778
    The objective of this study was to investigate the modulatory effect of Chlorella vulgaris on cultured fibroblast cells derived from young and old aged individuals focusing on DNA damage, telomere length and telomerase activity. Dose-response test of the algal extract on cells in both age groups revealed that optimum viability was observed at a concentration of 50 microg/ml. Results obtained showed that Chlorella vulgaris exhibited protective effects against H(2)O(2)-induced oxidative stress as shown by the reduction in damaged DNA caused by H(2)O(2) treatment (p<0.05) in Chlorella vulgaris pre- and post-treated groups (p<0.05). Pre-treatment of Chlorella vulgaris resulted in a significant decrease in DNA damage suggesting a bioprotective effect against free radical attacks. A decline in DNA damage was observed in post-treated cells which proves Chlorella vulgaris to present bioremediative properties. In cells induced with oxidative stress, telomere length decreased significantly coupled with a concomitant decline of telomerase activity (p<0.05). However, these reductions were prevented with prior and post treatment of Chlorella vulgaris. Therefore, we concluded that Chlorella vulgaris exhibited bioprotective effects especially in cells obtained from young donor but were more bioremediative for cells obtained from old donor as indicated by DNA damage, telomere shortening and reduction in telomerase activity.
    Matched MeSH terms: Dose-Response Relationship, Drug
  12. Anbu JS, Jayaraj P, Varatharajan R, Thomas J, Jisha J, Muthappan M
    Afr J Tradit Complement Altern Med, 2009 Jul 03;6(4):529-33.
    PMID: 20606773
    The ethanol and water extracts of Sansevieria trifasciata leaves showed dose-dependent and significant (P < 0.05) increase in pain threshold in tail-immersion test. Moreover, both the extracts (100 - 200 mg/kg) exhibited a dose-dependent inhibition of writhing and also showed a significant (P < 0.001) inhibition of both phases of the formalin pain test. The ethanol extract (200 mg/kg) significantly (P < 0.01) reversed yeast-induced fever. Preliminary phytochemical screening of the extracts showed the presence of alkaloids, flavonoids, saponins, glycosides, terpenoids, tannins, proteins and carbohydrates.
    Matched MeSH terms: Dose-Response Relationship, Drug
  13. Sharma JN, Stewart JM, Mohsin SS, Katori M, Vavrek R
    Agents Actions Suppl., 1992;38 ( Pt 3):258-69.
    PMID: 1334354
    We have evaluated the effects of a B2 receptor antagonist (B5630) of kinins on BK and captopril-induced acute hypotensive responses in anaesthetized SHR. Intravenous treatment of BK (1.0 microgram) and captopril (0.3 mg/kg) caused significant (p < 0.05) fall in the SBP and DBP. Whereas BK caused greater fall in the SBP (p < 0.05), DBP (p < 0.01) and duration of hypotension (p < 0.05) when administered after captopril (Fig 1 and 2). All the hypotensive effects of BK and captopril were significantly antagonised (p < 0.05) in the presence of B5630 (2.0 mg/kg). Further, the duration of hypotensive responses of BK and captopril were blocked (p < 0.05) by B5630. The agonists and BK-antagonist did not cause significant (p > 0.05) alterations in HR during the entire investigation. These findings provide evidence to support the suggestion that B2 receptor might be involved in the regulation of the hypotensive actions of BK and captopril. Kinins should also have valuable functions in the antihypertensive property of captopril-like drugs.
    Matched MeSH terms: Dose-Response Relationship, Drug
  14. Goh KL, Parasakthi N, Chuah SY, Cheah PL, Lo YL, Chin SC
    Aliment Pharmacol Ther, 1997 Dec;11(6):1115-8.
    PMID: 9663838
    OBJECTIVES: To determine and compare the efficacy and tolerability of two 1-week regimen comprising omeprazole, clarithromycin and amoxycillin or metronidazole in the eradication of Helicobacter pylori, and to determine the influence of bacterial resistance to metronidazole and clarithromycin on the outcome of treatment.

    PATIENTS AND METHODS: Patients with unequivocal evidence of H. pylori infection based on culture, histology and rapid urease test of both antrum and corpus biopsies were recruited for the study. The study was a randomized, investigator-blind, comparative study. Patients received either omeprazole 20 mg o.m., clarithromycin 250 mg b.d. and amoxycillin 500 mg b.d. (OAC) or omeprazole 20 mg o.m., metronidazole 400 mg b.d. and clarithromycin 250 mg b.d. (OMC) for 1 week. Patients were assessed for successful eradication, which was defined as absence of bacteria in all tests (culture, histology and urease test on both antral and corpus biopsies), at least 4 weeks after completion of therapy.

    RESULTS: Eighty-two patients were recruited for the study. Eradication rates on intention-to-treat analysis were--OAC: 36/41 (87.8%, 95% CI: 73.8, 95.9); OMC: 33/41 (80.5%, 95% CI: 65.1, 91.2). On per protocol analysis were--OAC: 36/40 (90%, 95% CI: 76.3, 97.2); OMC: 32/38 (84.2%, 95% CI: 68.7, 94.0). All side-effects encountered were mild and no patient discontinued treatment because of intolerance to medications. The most common side-effects were altered taste (OAC 31.7%, OMC 53.7%) and lethargy (OAC 14.6%, OMC 19.5%). Pre-treatment metronidazole resistance was encountered in 34/63 (54.0%) patients. No bacterial strains were found with primary resistance to clarithromycin. Metronidazole resistance did not significantly affect eradication rates. Emergence of resistance to clarithromycin was not seen post-therapy.

    CONCLUSIONS: Both the OAC and the OMC regimens were convenient and well-tolerated treatments for H. pylori. However, eradication rates were lower than anticipated.

    Matched MeSH terms: Dose-Response Relationship, Drug
  15. Yee A, Loh HS, Ong TA, Ng CG, Sulaiman AH
    Am J Mens Health, 2018 Sep;12(5):1705-1718.
    PMID: 29973132 DOI: 10.1177/1557988318784152
    Methadone is largely recognized as an effective treatment for opiate-dependent patients; however, it causes reduced brain dopaminergic action resulting in significant sexual dysfunction. Bupropion is a dopamine reuptake inhibitor which can potentially improve erectile function among male patients on methadone (MMT). This is a phase II, randomized, double-blind, parallel-group, placebo-controlled trial, involving 80 MMT male patients (73.4%) with mean age of 42.83 years ±9.68. These MMT male patients were randomly assigned into two groups to receive bupropion and placebo, respectively. The primary efficacy outcome measure was the difference between the two groups in end-point mean improvement scores using the measurement of Clinical Global Impression Scale adapted for Sexual Function (CGI-SF) at baseline (week 0) and at weeks 2, 4, and 6. Malay version of the sexual desire inventory-2 (SDI-2-BM) and Malay version of International Index of Erectile Function 15 (Mal-IIEF-15) domain scores were evaluated as secondary parameters. Improvement of the end-point mean from baseline were seen across the scores of SDI-2-BM (mean difference = 11.77 ± 2.90, 95% confidence interval (CI) [3.89, 19.54], p < .001) and Mal-IIEF-15 (mean difference = 8.37 ± 2.71, 95% CI [15.75, 0.99], p = .02), and the total plasma testosterone level (mean difference = 4.03, 95% CI [0.90, 7.15], p = .01). A categorical improvement of "much/very much improved" (CGI-SF score = 2) was reported by 58.3% ( n = 21/36) of bupropion SR-assigned versus 27.7% ( n = 10/36) placebo-assigned patient. Bupropion was well tolerated with no serious adverse events reported other than insomnia (17.7%). Six weeks of bupropion SR treatment reported significant improvement in key aspects of sexual function among male opiate-dependent patients on methadone maintenance treatment with emergent sexual dysfunction.
    Matched MeSH terms: Dose-Response Relationship, Drug
  16. Hui MT, Subash S, Wang CY
    Anaesthesia, 2011 Apr;66(4):274-7.
    PMID: 21401540 DOI: 10.1111/j.1365-2044.2011.06620.x
    The 50% and 95% effective doses of desflurane for removal of the classic laryngeal mask airway after suction of the upper airway, in anaesthetised spontaneously breathing adult patients, are not known. To determine these, we studied 38 healthy patients, aged between 18 and 44 years. The target desflurane concentration in each individual patient was determined by the Dixon up-and-down method. When the predetermined target end-tidal desflurane concentration reached steady state, we kept a constant end-expiratory partial pressure between the alveolus and the brain for 10 min before attempting to remove the classic laryngeal mask airway after suctioning the upper airway. The initial desflurane target concentration was set at 6% and up-down desflurane increments were 0.1%. This continued until there were at least six crossover pairs. From the probit analysis, the 50% effective dose of desflurane was 5.29% (95% CI 5.132-5.379%) and the 95% effective dose was 5.55% (95% CI 5.429-6.394%).
    Matched MeSH terms: Dose-Response Relationship, Drug
  17. Ngaha Njila MI, Massoma Lembè D, Koloko BL, Yong Meng G, Ebrahimi M, Awad EA, et al.
    Andrologia, 2019 Oct;51(9):e13359.
    PMID: 31353623 DOI: 10.1111/and.13359
    The effect of the methanolic extract of Alchornea cordifolia leaves on the fertility of senescent male rats was assessed in this study. 40 rats received daily distilled water, testosterone, 200 and 400 mg/kg of extract of Alchornea cordifolia. The reproductive organs weight, the gonadotropins, testosterone and cholesterol level, the sperm parameters, histology of the testes and epididymis were assessed. The weight of testes and prostate (400 mg/kg) significantly increased (p dose of 400 mg/kg, respectively, while the cholesterol decreased at a dose of 200 mg/kg (p dose of 400 mg/kg. The sperm count and morphology significantly increased at both doses of 200 mg/kg (p dose of 200 mg/kg and decreased at a dose of 400 mg/ kg. The overall results provide the strong evidence of the fertility potential of the methanolic extract of Alchornea cordifolia leaves in senescent male rats.
    Matched MeSH terms: Dose-Response Relationship, Drug
  18. Jafari S, Goh YM, Rajion MA, Jahromi MF, Ahmad YH, Ebrahimi M
    Anim Sci J, 2017 Feb;88(2):267-276.
    PMID: 27345820 DOI: 10.1111/asj.12634
    Papaya leaf methanolic extract (PLE) at concentrations of 0 (CON), 5 (LLE), 10 (MLE) and 15 (HLE) mg/250 mg dry matter (DM) with 30 mL buffered rumen fluid were incubated for 24 h to identify its effect on in vitro ruminal methanogenesis and ruminal biohydrogenation (BH). Total gas production was not affected (P > 0.05) by addition of PLE compared to the CON at 24 h of incubation. Methane (CH4 ) production (mL/250 mg DM) decreased (P 
    Matched MeSH terms: Dose-Response Relationship, Drug
  19. Kirton LG
    Ann Trop Med Parasitol, 2005 Oct;99(7):695-714.
    PMID: 16212803
    Citridiol is an extract of the leaves of Corymbia citriodora (Myrtaceae), the lemon eucalyptus, and mostly consists of p-menthane-3,8-diol isomers. The effectiveness of this extract as a repellent against land leeches of the genus Haemadipsa (Haemadipsidae), primarily H. sylvestris, was tested in the laboratory and field, in Peninsular Malaysia. The formulation tested, Mosi-guard Natural spray, contained 40% (w/w) Citridiol in a base of ethanol, water and isopropanol. In the laboratory test, specimens of H. sylvestris that were placed within moist, untreated arenas enclosed by treated paper rings made numerous attempts to cross the rings but were prevented or delayed from crossing over, in a dose-dependent manner. Mortality was high among the leeches that attempted to cross over the paper rings that had been sprayed to saturation point but low among the leeches that attempted to cross over paper rings that had only been partially treated, with a droplet-spray. The field study was carried out using indices that were formulated to reflect the severity of leech attack and the degree of repellency. Heavy or moderate spraying of footwear and trouser legs (tucked into socks) not only gave complete protection against bites by H. sylvestris and H. picta but also provided high enough repellency to keep the treated footwear virtually free of leeches. Even a light spray greatly reduced the numbers of leeches on footwear and delayed their progression toward biting the test subjects, although it failed to prevent bites completely. There was no decline in the repellency of the Citridiol when hourly assessments were made over a 6-h test period in the field. The results of the study show that Citridiol is highly repellent as well as toxic to leeches, and can be effectively used to prevent leech bites in the field.
    Matched MeSH terms: Dose-Response Relationship, Drug
  20. Peck CC, Lewis AN, Joyce BE
    Ann Trop Med Parasitol, 1975 Jun;69(2):141-5.
    PMID: 1155986
    Serum was collected from six adults participating in a field trial of sulfadoxine and pyrimethamine in combination which was being administered once monthly for malaria suppression. Samples were drawn during each of two consecutive months three hours, and 7, 14 and 28 days following a dose of 1 500 mg sulfadoxine. Serum sulfadoxine concentration was measured using the method of Bratton and Marshall (1939). Initial serum concentrations averaged 19-9 plus or minus 2-4 (SD) mg/100 ml and decayed to 6-2 plus or minus 2-8 mg/100 ml at 14 days. Serum sulfadoxine concentrations were still detectable at 28 days following a dose (2-1 plus or minus 1-5 mg/100 ml). Elimination half-time averaged 195 plus or minus 44 hours. The presistent serum concentrations of sulfadoxine following monthly doses documented here during field-use of this drug are in agreement with the successful clinical results reported for such a regimen (Lewis and Ponnampalam, 1974; O'Holohan and Hugoe-Mathews, 1971; Wolfensberger, 1971).
    Matched MeSH terms: Dose-Response Relationship, Drug
Contact Us

Please provide feedback to Administrator (afdal@afpm.org.my)

External Links