Micro-influence of vacuum block positions on machinability of acrylic using hybrid vacuum clamping system

The double-sided vacuum clamper is used in this project to study the engraving and end mill machining output. This paper proposes a mechanical repair solution for clamping which does not leave any trace on the clamped surface and can accommodate tiny workpiece thicknesses. Mass production must rapidly and efficiently locate the workpiece for specific operations. Using vacuum clamp, which can often clamp small, thin parts, to attach and release the workpiece. The hybrid vacuum system capable to support the capacity of machining with two conditions: continuous air pressure and remained air pressure from the compressor. The design of the dual side vacuum block is fully designed with the software SolidWorks, which is analyzed the mechanical properties by using the Static Analysis Simulation. The findings show that the solid vacuum block Delrin led to improved static analysis results. CNC router machine used in the experiments, with a 3 mm diameter to engrave and end milling process to acrylic workpiece. After the experiment, an evaluation has been made on the extent of precision and surface roughness. The most ideal position of the vacuum clamping is side by side with distance due to the nearer clamping force

Computational and experimental approaches in understanding the therapeutic potential of Ficus deltoidea Jack leaf extract / Amirul Ridzuan Abu Bakar

Ficus deltoidea Jack of family Moraceae (FD) is a native shrub in Malaysia that are well known for its ethno-pharmaceutical and therapeutic properties. In this study, computational and experimental approaches were adopted to unravel the therapeutic properties of the FD leaf. Initially, quality control and safety assessment on the FD leaf were undertaken. The findings from this analysis revealed that the FD leaf of high quality, purity and abide by the safety requirements set by the regulatory body. FD leaf was solvent extracted as 50% (v/v) ethanol water extract. Standardization using high performance liquid chromatography (HPLC) revealed vitexin and isovitexin as the major chemical compounds in the FD leaf 50% (v/v) ethanol water extract. FD leaf 50% (v/v) ethanol water extract and its major chemical compounds (vitexin and isovitexin) were subjected to a selected panel of enzymatic inhibition assay, namely, α-amylase and matrix metalloproteinases (MMP-2, MMP-8 and MMP-9). The results showed that FD leaf 50% (v/v) ethanol water extract, vitexin and isovitexin exhibited inhibition property against the selected enzyme panels. Then, computational analyses (molecular docking and molecular dynamic simulation) revealed the molecular interaction and ligand-protein complex stability between vitexin and isovitexin against the selected enzyme panels. FD leaf 50% (v/v) ethanol water extract also showed antioxidant activity based on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and in vitro cytotoxicity based on 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium Bromide (MTT) assay revealed the IC50 of the extract was at 221 μg/ml on EA.hy926 cells. FD leaf 50% (v/v) ethanol water extract also demonstrated cell migration inhibitory effect on EA.hy926 cells in a dose and time-dependent manner with the highest activity tested at 300 μg/ml after 24 hours treatment. The biological activity of FD leaf 50% (v/v) ethanol water extract was further studied using 2 types of in vivo animal models (healthy and streptozotocin-induced diabetic Sprague-Dawley rats). Toxicology analysis was conducted at 1000 mg/kg of FD leaf 50% (v/v) ethanol water extract. Visual inspection, blood analysis and histology analysis revealed no acute toxicity of the leaf extract at the tested concentration. Wound healing activity of FD leaf 50% (v/v) ethanol water extract was studied on both animal models. FD leaf 50% (v/v) ethanol water extract showed highest wound healing property at 100 mg/ml and the diabetic rat model showed faster wound closure rate compared to the healthy rat model. Finally, this study provided comprehensive and valuable information on the potential of FD leaf extract for therapeutic application especially for the wound healing in diabetic cases

Experimental and computational approaches to reveal the potential of Ficus deltoidea leaves extract as α-amylase inhibitor

Ficus deltoidea leaves extract are known to have good therapeutic properties such as antioxidant, anti-inflammatory and anti-diabetic. We showed that 50% ethanol-water extract of F. deltoidea leaves and its pungent compounds vitexin and isovitexin exhibited significant (p < 0.05) α-amylase inhibition with IC50 (vitexin: 4.6 μM [0.02 μg/mL]; isovitexin: 0.06 μg/mL [13.8 μM] and DPPH scavenging with IC50 (vitexin: 92.5 μM [0.4 μg/mL]; isovitexin: 0.5 μg/mL [115.4 μM]). Additionally, molecular docking analysis confirmed that vitexin has a higher binding affinity (-7.54 kcal/mol) towards α-amylase compared to isovitexin (−5.61 kcal/mol). On the other hand, the molecular dynamics findings showed that vitexin-α-amylase complex is more stable during the simulation of 20 ns when compared to the isovitexin-α-amylase complex. Our results suggest that vitexin is more potent and stable against α-amylase enzyme, thus it could develop as a therapeutic drug for the treatment of diabetes

Enzymatic inhibitory activity of Ficus deltoidea leaf extract on matrix metalloproteinase-2, 8 and 9

Dysregulation of matrix metalloproteinases (MMPs) activity is known in many pathological conditions with which most of the conditions are related to elevate MMPs activities. Ficus deltoidea (FD) is a plant known for its therapeutic properties. In order to evaluate the therapeutic potential of FD leaf extract, we study the enzymatic inhibition properties of FD leaf extract and its major bioactive compounds (vitexin and isovitexin) on a panel of MMPs (MMP-2, MMP-8 and MMP-9) using experimental and computational approaches. FD leaf extract and its major bioactive compounds showed pronounced inhibition activity towards the MMPs tested. Computational docking analysis revealed that vitexin and isovitexin bind to the active site of the three tested MMPs. We also evaluated the cytotoxicity and cell migration inhibition activity of FD leaf extract in the endothelial EA.hy 926 cell line. Conclusively, this study provided additional information on the potential of FD leaf extract for therapeutical application. © 2018, © 2018 Informa UK Limited, trading as Taylor & Francis Group

Experimental and computational approaches to reveal the potential of <i>Ficus deltoidea</i> leaves extract as α-amylase inhibitor

<p><i>Ficus deltoidea</i> leaves extract are known to have good therapeutic properties such as antioxidant, anti-inflammatory and anti-diabetic. We showed that 50% ethanol-water extract of <i>F. deltoidea</i> leaves and its pungent compounds vitexin and isovitexin exhibited significant (<i>p</i> < 0.05) α-amylase inhibition with IC₅₀ (vitexin: 4.6 μM [0.02 μg/mL]; isovitexin: 0.06 μg/mL [13.8 μM] and DPPH scavenging with IC₅₀ (vitexin: 92.5 μM [0.4 μg/mL]; isovitexin: 0.5 μg/mL [115.4 μM]). Additionally, molecular docking analysis confirmed that vitexin has a higher binding affinity (-7.54 kcal/mol) towards α-amylase compared to isovitexin (−5.61 kcal/mol). On the other hand, the molecular dynamics findings showed that vitexin-α-amylase complex is more stable during the simulation of 20 ns when compared to the isovitexin-α-amylase complex. Our results suggest that vitexin is more potent and stable against α-amylase enzyme, thus it could develop as a therapeutic drug for the treatment of diabetes.</p

Enzymatic inhibitory activity of <i>Ficus deltoidea</i> leaf extract on matrix metalloproteinase-2, 8 and 9

<p>Dysregulation of matrix metalloproteinases (MMPs) activity is known in many pathological conditions with which most of the conditions are related to elevate MMPs activities. <i>Ficus deltoidea</i> (FD) is a plant known for its therapeutic properties. In order to evaluate the therapeutic potential of FD leaf extract, we study the enzymatic inhibition properties of FD leaf extract and its major bioactive compounds (vitexin and isovitexin) on a panel of MMPs (MMP-2, MMP-8 and MMP-9) using experimental and computational approaches. FD leaf extract and its major bioactive compounds showed pronounced inhibition activity towards the MMPs tested. Computational docking analysis revealed that vitexin and isovitexin bind to the active site of the three tested MMPs. We also evaluated the cytotoxicity and cell migration inhibition activity of FD leaf extract in the endothelial EA.hy 926 cell line. Conclusively, this study provided additional information on the potential of FD leaf extract for therapeutical application.</p

Paediatric COVID-19 mortality: a database analysis of the impact of health resource disparity

Background The impact of the COVID-19 pandemic on paediatric populations varied between high-income countries (HICs) versus low-income to middle-income countries (LMICs). We sought to investigate differences in paediatric clinical outcomes and identify factors contributing to disparity between countries.Methods The International Severe Acute Respiratory and Emerging Infections Consortium (ISARIC) COVID-19 database was queried to include children under 19 years of age admitted to hospital from January 2020 to April 2021 with suspected or confirmed COVID-19 diagnosis. Univariate and multivariable analysis of contributing factors for mortality were assessed by country group (HICs vs LMICs) as defined by the World Bank criteria.Results A total of 12 860 children (3819 from 21 HICs and 9041 from 15 LMICs) participated in this study. Of these, 8961 were laboratory-confirmed and 3899 suspected COVID-19 cases. About 52% of LMICs children were black, and more than 40% were infants and adolescent. Overall in-hospital mortality rate (95% CI) was 3.3% [=(3.0% to 3.6%), higher in LMICs than HICs (4.0% (3.6% to 4.4%) and 1.7% (1.3% to 2.1%), respectively). There were significant differences between country income groups in intervention profile, with higher use of antibiotics, antivirals, corticosteroids, prone positioning, high flow nasal cannula, non-invasive and invasive mechanical ventilation in HICs. Out of the 439 mechanically ventilated children, mortality occurred in 106 (24.1%) subjects, which was higher in LMICs than HICs (89 (43.6%) vs 17 (7.2%) respectively). Pre-existing infectious comorbidities (tuberculosis and HIV) and some complications (bacterial pneumonia, acute respiratory distress syndrome and myocarditis) were significantly higher in LMICs compared with HICs. On multivariable analysis, LMIC as country income group was associated with increased risk of mortality (adjusted HR 4.73 (3.16 to 7.10)).Conclusion Mortality and morbidities were higher in LMICs than HICs, and it may be attributable to differences in patient demographics, complications and access to supportive and treatment modalities

ISARIC-COVID-19 dataset: A Prospective, Standardized, Global Dataset of Patients Hospitalized with COVID-19

The International Severe Acute Respiratory and Emerging Infection Consortium (ISARIC) COVID-19 dataset is one of the largest international databases of prospectively collected clinical data on people hospitalized with COVID-19. This dataset was compiled during the COVID-19 pandemic by a network of hospitals that collect data using the ISARIC-World Health Organization Clinical Characterization Protocol and data tools. The database includes data from more than 705,000 patients, collected in more than 60 countries and 1,500 centres worldwide. Patient data are available from acute hospital admissions with COVID-19 and outpatient follow-ups. The data include signs and symptoms, pre-existing comorbidities, vital signs, chronic and acute treatments, complications, dates of hospitalization and discharge, mortality, viral strains, vaccination status, and other data. Here, we present the dataset characteristics, explain its architecture and how to gain access, and provide tools to facilitate its use

Association of Country Income Level With the Characteristics and Outcomes of Critically Ill Patients Hospitalized With Acute Kidney Injury and COVID-19

Introduction: Acute kidney injury (AKI) has been identified as one of the most common and significant problems in hospitalized patients with COVID-19. However, studies examining the relationship between COVID-19 and AKI in low- and low-middle income countries (LLMIC) are lacking. Given that AKI is known to carry a higher mortality rate in these countries, it is important to understand differences in this population. Methods: This prospective, observational study examines the AKI incidence and characteristics of 32,210 patients with COVID-19 from 49 countries across all income levels who were admitted to an intensive care unit during their hospital stay. Results: Among patients with COVID-19 admitted to the intensive care unit, AKI incidence was highest in patients in LLMIC, followed by patients in upper-middle income countries (UMIC) and high-income countries (HIC) (53%, 38%, and 30%, respectively), whereas dialysis rates were lowest among patients with AKI from LLMIC and highest among those from HIC (27% vs. 45%). Patients with AKI in LLMIC had the largest proportion of community-acquired AKI (CA-AKI) and highest rate of in-hospital death (79% vs. 54% in HIC and 66% in UMIC). The association between AKI, being from LLMIC and in-hospital death persisted even after adjusting for disease severity. Conclusions: AKI is a particularly devastating complication of COVID-19 among patients from poorer nations where the gaps in accessibility and quality of healthcare delivery have a major impact on patient outcomes