MATERIAL AND METHOD: The total phenolic content (TPC), 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging and ferric-ion reducing power (FRAP) were used to evaluate their antioxidant capacity. Tyrosinase inhibition effect was measured using mushroom tyrosinase inhibition assay.
RESULT: Ethyl acetate extract of P. macrocarpa's stem exhibited highest total phenolic content, DPPH free radical scavenging and ferric reducing power. Meanwhile, chloroform extracts of leaves and fruits demonstrated potent anti-tyrosinase activities as compared to a well-known tyrosinase inhibitor, kojic acid.
CONCLUSION: Since chloroform extracts of leaves and fruits have low antioxidant capacities, the tyrosinase inhibition effect observed are antioxidant independent. This study suggests direct tyrosinase inhibition by chloroform extracts of Phaleria macrocarpa.
MATERIAL AND METHODS: Seaweeds were extracted with ethanol and further fractionated with hexane, ethyl acetate and water. The extracts were tested for mushroom tyrosinase inhibitory activity, cytotoxicity in human epidermal melanocyte (HEM), and Chang cells. Extracts with potent melanocytotoxicity were formulated into cosmetic cream and tested on guinea pigs in dermal irritation tests and de-pigmentation assessments.
RESULTS: Both Sargassum polycystum and Padina tenuis seaweeds showed significant inhibitory effect on mushroom tyrosinase in the concentration tested. SPEt showed most potent cytotoxicity on HEM (IC50 of 36µg/ml), followed by SPHF (65µg/ml), and PTHF (78.5µg/ml). SPHF and SPEt reduced melanin content in skin of guinea pigs when assessed histologically.
CONCLUSION: SPEt, SPHF and PTHF were able to inhibit HEM proliferation in vitro, with SPHF being most potent and did not cause any dermal irritation in guinea pigs. The results obtained indicate that SPHF is a promising pharmacological or cosmetic agent.
METHOD: Literature search was performed within the PubMed, ScienceDirect.com and Google Scholar.
RESULTS: The presence of proline at the C-terminal tripeptide of ACE inhibitor can competitively inhibit the ACE activity. The effects of other amino acids are less studied leading to difficulties in predicting potent peptide sequences. The broad specificity of the enzyme may be due to the dual active sites observed on the somatic ACE. The inhibitors may not necessarily competitively inhibit the enzyme which explains why some reported inhibitors do not have the common ACE inhibitor characteristics. Finally, the in vivo assay has to be carried out before the peptides as the antihypertensive agents can be claimed. The peptides must be absorbed into circulation without being degraded, which will affect their bioavailability and potency. Thus, peptides with strong in vitro IC50 values do not necessarily have the same effect in vivo and vice versa.
CONCLUSION: The relationship between peptide amino acid sequence and inhibitory activity, in vivo studies of the active peptides and bioavailability must be studied before the peptides as antihypertensive agents can be claimed.
METHODS: TIPS-3 is a 2x2x2 factorial randomized controlled trial that will examine the effect of a FDC polypill on major CV outcomes in a primary prevention population. This study aims to determine whether the Polycap (comprised of atenolol, ramipril, hydrochlorothiazide, and a statin) reduces CV events in persons without a history of CVD, but who are at least at intermediate CVD risk. Additional interventions in the factorial design of the study will compare the effect of (1) aspirin versus placebo on CV events (and cancer), (2) vitamin D versus placebo on the risk of fractures, and (3) the combined effect of aspirin and the Polycap on CV events.
RESULTS: The study has randomized 5713 participants across 9 countries. Mean age of the study population is 63.9 years, and 53% are female. Mean INTERHEART risk score is 16.8, which is consistent with a study population at intermediate CVD risk.
CONCLUSION: Results of the TIP-3 study will be key to determining the appropriateness of FDC therapy as a strategy in the global prevention of CVD.
METHODS: We systematically reviewed the published studies to assess the association of RAS inhibitors with mortality as well as disease severity in COVID-19 patients. A systematic literature search was performed to retrieve relevant original studies investigating mortality and severity (severe/critical disease) in COVID-19 patients with and without exposure to RAS inhibitors.
RESULTS: A total of 59 original studies were included for qualitative synthesis. Twenty-four studies that reported adjusted effect sizes (24 studies reported mortality outcomes and 16 studies reported disease severity outcomes), conducted in RAS inhibitor-exposed and unexposed groups, were pooled in random-effects models to estimate overall risk. Quality assessment of studies revealed that most of the studies included were of fair quality. The use of an ACEI/ARB in COVID-19 patients was significantly associated with lower odds (odds ratio [OR] = 0.73, 95% confidence interval [CI] 0.56-0.95; n = 18,749) or hazard (hazard ratio [HR] = 0.75, 95% CI 0.60-0.95; n = 26,598) of mortality compared with non-use of ACEI/ARB. However, the use of an ACEI/ARB was non-significantly associated with lower odds (OR = 0.91, 95% CI 0.75-1.10; n = 7446) or hazard (HR = 0.73, 95% CI 0.33-1.66; n = 6325) of developing severe/critical disease compared with non-use of an ACEI/ARB.
DISCUSSION: Since there was no increased risk of harm, the use of RAS inhibitors for hypertension and other established clinical indications can be maintained in COVID-19 patients.
OBJECTIVES: To investigate adherence to guideline-based management and mortality of STEMI patients in Malaysia.
DESIGN: Retrospective analysis.
SETTINGS: STEMI patients from 18 participating hospital across Malaysia included in the National Cardiovascular Database-Acute Coronary Syndrome (NCVD-ACS) registry year 2006 to 2013.
PATIENTS AND METHODS: Patients were categorized into four subgroups based on the year of admission (2006 to 2007, 2008 to 2009, 2010 to 2011 and 2012 to 2013). Baseline characteristics and clinical presentation, in-hospital pharmacotherapy, invasive revascularization and in-hospital/30-day mortality were analysed and compared between the subgroups.
MAIN OUTCOME MEASURE(S): Rate of in-hospital catheterization/percutaneous coronary intervention.
RESULTS: The registry contained data on 19483 patients. Intravenous thrombolysis was the main reperfusion therapy. Although the overall rate of in-hospital catheterisation/PCI more than doubled over the study period, while the use of primary PCI only slowly increased from 7.6% in 2006/2007 to 13.6% in 2012/2013. The use of evidence-based oral therapies increased steadily over the years except for ACe-inhibitors and angiotensin-receptor blockers. The adjusted risk ratios (RR) for in-hospital mortality for the four sub-groups have not shown any significant improvement. The 30-day adjusted risk ratios however showed a significant albeit gradual risk reduction (RR 0.773 95% CI 0.679-0.881, P < .001).
CONCLUSION: Adherence to evidence-based treatment in STEMI in Malaysia is still poor especially in terms of the rate of primary PCI. Although there is a general trend toward reduced 30-day mortality, the reduction was only slight over the study period. Drastic effort is needed to improve adherence and clinical outcomes.
LIMITATION: Retrospective registry data with inter-hospital variation.
OBJECTIVE: The present work aimed to evaluate their cytotoxicity against HepG2 (hepatocellular carcinoma), A549 (pulmonary adenocarcinoma), MCF-7 (breast adenocarcinoma) and WRL 68 (embryonic liver) cell lines.
METHODS: MTT assay was employed to investigate the cytotoxicity, and a tyrosinase inhibitor screening kit was used to evaluate the Tyrosinase (TYR) inhibitory activity of the targets.
RESULTS: The tested compounds exhibited no considerable cytotoxicity, and nine of them were selected for a tyrosinase inhibitory test. Compounds 2b, 2m, and 5a showed good inhibitory percentages against TYR compared to that of kojic acid (reference substance). Molecular docking was performed to rationalize the Structure-Activity Relationship (SAR) of the target pyridotriazolopyrimidines and analyze the binding between the docked-selected compounds and the amino acid residues in the active site of tyrosinase.
CONCLUSION: The target pyridotriazolopyrimidines were identified as a new class of tyrosinase inhibitors.