Displaying publications 81 - 100 of 843 in total

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  1. Mohd Isha NS, Mohd Kusin F, Ahmad Kamal NM, Syed Hasan SNM, Molahid VLM
    Environ Geochem Health, 2021 May;43(5):2065-2080.
    PMID: 33392897 DOI: 10.1007/s10653-020-00784-z
    This paper attempts to evaluate the mineralogical and chemical composition of sedimentary limestone mine waste alongside its mineral carbonation potential. The limestone mine wastes were recovered as the waste materials after mining and crushing processes and were analyzed for mineral, major and trace metal elements. The major mineral composition discovered was calcite (CaCO3) and dolomite [CaMg(CO3)2], alongside other minerals such as bustamite [(Ca,Mn)SiO3] and akermanite (Ca2MgSi2O7). Calcium oxide constituted the greatest composition of major oxide components of between 72 and 82%. The presence of CaO facilitated the transformation of carbon dioxide into carbonate form, suggesting potential mineral carbonation of the mine waste material. Geochemical assessment indicated that mean metal(loid) concentrations were found in the order of Al > Fe > Sr > Pb > Mn > Zn > As > Cd > Cu > Ni > Cr > Co in which Cd, Pb and As exceeded some regulatory guideline values. Ecological risk assessment demonstrated that the mine wastes were majorly influenced by Cd as being classified having moderate risk. Geochemical indices depicted that Cd was moderately accumulated and highly enriched in some of the mine waste deposited areas. In conclusion, the limestone mine waste material has the potential for sequestering CO2; however, the presence of some trace metals could be another important aspect that needs to be considered. Therefore, it has been shown that limestone mine waste can be regarded as a valuable feedstock for mineral carbonation process. Despite this, the presence of metal(loid) elements should be of another concern to minimize potential ecological implication due to recovery of this waste material.
    Matched MeSH terms: Calcium Compounds/analysis; Calcium Compounds/chemistry
  2. Salman M, Khan AH, Syed Sulaiman SA, Hughes JD, Khan JH, Shehzadi N, et al.
    J Pak Med Assoc, 2021 May;71(5):1384-1387.
    PMID: 34091619 DOI: 10.47391/JPMA.1162
    Objective: To investigate the prevalence and severity of lower urinary tract symptoms among calcium channel blocker users, and the impact on patients' quality of life.

    METHODS: The cross-sectional study was conducted at one hospital and 2 community pharmacies in Lahore, Pakistan, from November 2017 to July 2018, and comprised patients using calcium channel blockers. Data was collected using standardised scales to assess lower urinary tract symptoms and quality of life. Data was analysed using SPSS 22.

    RESULTS: Of the 410 subjects, 315 (76.8%) were males. The overall median age was 50.84 years, IQR 19 with 126 (30.7%) aged 41-50 years. Of the total, 108 (26.3%) patients were on calcium channel blockers alone, while the rest were taking it in combination with other drugs. Prevalence of lower urinary tract symptoms was 307 (74.9%); mild 103 (25.1%), moderate 201 (49.1%) and severe 106 (25.9%). The symptoms were significantly associated with reduced quality of life (p<0.05).

    Conclusion: Majority calcium channel blockers users had clinically significant lower urinary tract symptoms which significantly reduced patients' quality of life.

    Matched MeSH terms: Calcium Channel Blockers/therapeutic use
  3. Mohamad NV, Ima-Nirwana S, Chin KY
    Biomed Pharmacother, 2021 May;137:111368.
    PMID: 33582449 DOI: 10.1016/j.biopha.2021.111368
    Tocotrienol has been shown to prevent bone loss in animal models of postmenopausal osteoporosis, but the low oral bioavailability might limit its use. A self-emulsifying drug delivery system (SEDDS) could increase the bioavailability of tocotrienol. However, evidence of this system in improving the skeletal effects of tocotrienol is scanty. This study aims to evaluate the therapeutic efficacy of annatto tocotrienol with SEDDS in a rat model of postmenopausal bone loss. Ten-month-old female Sprague Dawley rats were randomized into six groups. The baseline group was euthanatized at the onset of the study. Four other groups underwent ovariectomy to induce estrogen deficiency. The sham underwent similar surgery procedure, but their ovaries were retained. Eight weeks after surgery, the ovariectomized rats received one of the four different regimens orally daily: (a) SEDDS, (b) annatto tocotrienol [60 mg/kg body weight (b.w.)] without SEDDS, (c) annatto-tocotrienol (60 mg/kg b.w.) with SEDDS, (d) raloxifene (1 mg/kg b.w.). After eight weeks of treatment, blood was collected for the measurement of delta-tocotrienol level and oxidative stress markers. The rats were euthanized and their bones were harvested for the evaluation of the bone microstructure, calcium content and strength. Circulating delta-tocotrienol level was significantly higher in rats receiving annatto tocotrienol with SEDDS compared to the group receiving unformulated annatto-tocotrienol (p calcium content, increased bone biomechanical strength and increased antioxidant enzyme activities compared with the ovariectomized group (p 
    Matched MeSH terms: Calcium/metabolism
  4. Iqbal DM, Wong LS, Kong SY
    Materials (Basel), 2021 Apr 23;14(9).
    PMID: 33922871 DOI: 10.3390/ma14092175
    The rapid development of the construction sector has led to massive use of raw construction materials, which are at risk of exhaustion. The problem is aggravated by the high demand for cement as binding powder and the mass production of clay bricks for construction purposes. This scenario has led to high energy consumption and carbon emissions in their production. In this regard, bio-cementation is considered a green solution to building construction, because this technology is environmentally friendly and capable of reducing carbon emissions, thus slowing the global warming rate. Most of the previously published articles have focused on microbiologically induced calcium carbonate precipitation (MICP), with the mechanism of bio-cementation related to the occurrence of urea hydrolysis as a result of the urease enzymatic activity by the microbes that yielded ammonium and carbonate ions. These ions would then react with calcium ions under favorable conditions to precipitate calcium carbonate. MICP was investigated for crack repair and the surface treatment of various types of construction materials. Research on MICP for the production of binders in construction materials has become a recent trend in construction engineering. With the development of cutting edge MICP research, it is beneficial for this article to review the recent trend of MICP in construction engineering, so that a comprehensive understanding on microbial utilization for bio-cementation can be achieved.
    Matched MeSH terms: Calcium Carbonate
  5. Leong HY, Chang CK, Khoo KS, Chew KW, Chia SR, Lim JW, et al.
    Biotechnol Biofuels, 2021 Apr 07;14(1):87.
    PMID: 33827663 DOI: 10.1186/s13068-021-01939-5
    Global issues such as environmental problems and food security are currently of concern to all of us. Circular bioeconomy is a promising approach towards resolving these global issues. The production of bioenergy and biomaterials can sustain the energy-environment nexus as well as substitute the devoid of petroleum as the production feedstock, thereby contributing to a cleaner and low carbon environment. In addition, assimilation of waste into bioprocesses for the production of useful products and metabolites lead towards a sustainable circular bioeconomy. This review aims to highlight the waste biorefinery as a sustainable bio-based circular economy, and, therefore, promoting a greener environment. Several case studies on the bioprocesses utilising waste for biopolymers and bio-lipids production as well as bioprocesses incorporated with wastewater treatment are well discussed. The strategy of waste biorefinery integrated with circular bioeconomy in the perspectives of unravelling the global issues can help to tackle carbon management and greenhouse gas emissions. A waste biorefinery-circular bioeconomy strategy represents a low carbon economy by reducing greenhouse gases footprint, and holds great prospects for a sustainable and greener world.
    Matched MeSH terms: Calcium Phosphates
  6. Özkaya D, Nazıroğlu M, Vanyorek L, Muhamad S
    Biol Trace Elem Res, 2021 Apr;199(4):1356-1369.
    PMID: 33389617 DOI: 10.1007/s12011-020-02556-3
    Hypoxia (HYPX) in several eye diseases such as glaucoma and diabetic retinopathy causes oxidative cell death and inflammation. TRPM2 cation channel is activated by HYPX-induced ADP-ribose (ADPR) and oxidative stress. The protective role of selenium via inhibition of TRPM2 on the HYPX-induced oxidative cytotoxicity and inflammation values in the human kidney cell line was recently reported. However, the protective role of selenium nanoparticles (SeNP) on the values in the retinal pigment epithelial (ARPE-19) cells has not been clarified yet. In the current study, we investigated two subjects. First, we investigated the involvement of TRPM2 channel on the HYPX-induced oxidative injury, inflammation, and apoptosis in the ARPE-19 cells. Second, we investigated the protective role of SeNP via inhibition of TRPM2 channel on the HYPX-induced oxidative injury and apoptosis in the ARPE-19 cells. For the aims, the ARPE-19 cells were divided into four main groups as follows: Control (Ctr), SeNP (2.5 μg/ml for 24 h), HYPX (200 μM CoCl2 for 24 h), and HYPX+SeNP. The TRPM2 current density and Ca2+ fluorescence intensity with an increase of mitochondrial membrane depolarization and oxygen free radical (OFR) generations were increased in the ARPE-19 cells by the treatment of HYPX. There was no increase of Ca2+ fluorescence intensity in the pre-treated cells with PARP-1 inhibitors (DPQ and PJ34) or in the presence of Ca2+-free extracellular buffer. When HYPX-induced TRPM2 activity was treated by SeNP and TRPM2 (2-APB and ACA) blockers, the increases of OFR generation, cytokine (TNF-α and IL-1β) levels, TRPM2, and PARP-1 expressions were restored. In conclusion, the exposure of HYPX caused mitochondrial oxidative cell cytotoxicity and cell death via TRPM2-mediated Ca2+ signaling and may provide an avenue for treating HYPX-induced retinal diseases associated with the excessive OFR and Ca2+ influx.
    Matched MeSH terms: Calcium/metabolism
  7. Kok ESK, Lim XJ, Chew SX, Ong SF, See LY, Lim SH, et al.
    BMC Oral Health, 2021 03 12;21(1):116.
    PMID: 33711992 DOI: 10.1186/s12903-021-01470-x
    BACKGROUND: Compare antimicrobial efficacy of a quarternary ammonium silane (QAS)/k21 as an intracanal medicament against E. faecalis and C. albicans biofilms formed on root dentin.

    METHODOLOGY: Dentin blocks were sterilized and E. faecalis and C. albicans microbial colonies were counted for colony-forming-units against 2%k21, 2%CHX and Ca(OH)2 medicaments. Biofilm colonies after 7 days on dentin were analysed using confocal laser scanning microscopy with live/dead bacterial viability staining. TEM was done to study dentin collagen matrix. Dentin discs from 3rd day and 7th day well plate was used for Raman spectra and observed under fluorescent-microscope. Docking studies were carried out on MMP-2 S1 binding-domain with k21.

    RESULTS: There was reduction of E. faecalis/C. albicans when k21, chlorhexidine and calcium hydroxide were used with highest percentage in 2%k21 treated specimens. 2%k21 showed dense and regular collagen network with intact cross-banding and decreased Raman intensity for 2%k21 on 3rd day. NaOCl + k21 showed least adherence, whereas saline groups showed highest adherence of E. faecalis and C. albicans to root-canal dentin. Alizarin red staining of hDPSCs revealed calcium deposition in all groups with significant difference seen amongst 2%k21 groups. MMP-2 ligand binding was seen accurately indicating possible target sites for k21 intervention.

    CONCLUSION: 2%k21 can be considered as alternative intracanal medicament.

    Matched MeSH terms: Calcium Hydroxide
  8. Gupta R, Kewalramani R
    J Oral Biol Craniofac Res, 2021 03 10;11(2):330-333.
    PMID: 33786296 DOI: 10.1016/j.jobcr.2021.03.001
    Aim: To evaluate the microleakage of newer bioceramic root-end filling materials.

    Material and method: Sixty freshly extracted human single-rooted mandibular premolar teeth were selected for the study. Teeth with fractured root, cracks, anddilacerations were rejected. All teeth were cleaned with ultrasonic scalers. Standard access opening was done and root canal treatment was performed with rotary files followed by obturation. After storing in saline for a week apical 3 ​mm of the root was resected at 900 angles to the long axis of the root. Retro cavity preparation was done with ultrasonic tips. The teeth were divided into four groups of 15 specimens each. Group I - Biodentin, GroupII-Bioaggregate, Group III - MTA Plus, and Group IV - MTA. After the restoration of retro cavities of all the teeth as per manufacture instructions, two coats of nail varnish were applied to leave apical 3 ​mm. All teeth were stored in 2% methylene blue for 72 ​h followed by emersion in 65% nitric acid for the next 72 ​h for Dye extraction. The obtained supernatant solution was then centrifuged and optical density or absorbance was measured with a UV spectrophotometer.

    Result: Microleakage was found to be increasing in this order: Biodentin ​ ​0.01).

    Conclusion: All materials exhibit some amount of microleakage. Biodentin shows the least microleakage among all the bioceramic material groups. Hence, Biodentin and bioaggregate are better material of choice for the retrograde filling to prevent microleakage.

    Matched MeSH terms: Calcium Hydroxide
  9. Eliaslankaran Z, Daud NNN, Yusoff ZM, Rostami V
    Materials (Basel), 2021 Feb 28;14(5).
    PMID: 33670914 DOI: 10.3390/ma14051140
    Coastal accretion and erosion are unavoidable processes as some coastal sediments undergo modification and stabilization. This study was conducted to investigate the geotechnical behavior of soil collected from Bagan Lalang coast and treated with lime, cement, and rice husk ash (RHA) to design a low-cost alternative mixture with environmentally friendly characteristics. Laboratory tests were carried out to analyze the physical properties of the soil (Atterberg limits and compaction properties), together with mechanical characteristics (direct shear and unconfined compressive strength (UCS) tests) to determine the effect of different ratios of stabilizer/pozzolan on the coastal soil and the optimum conditions for each mixture. Part of the purpose of this study was also to analyze the shear behavior of the coastal soil and monitor the maximum axial compressive stress that the treated specimens can bear under zero confining pressure. Compared to the natural soil, the soil treated with lime and rice husk ash (LRHA) in the ratio of 1:2 (8% lime content) showed a tremendous increase in shear stress under the normal stress of 200 kPa. The strength parameters such as the cohesion (c) and internal friction angle (ϕ) values showed a significant increase. Cohesion values increased considerably in samples cured for 90 days compared to specimens cured for 7 days with additional LRHA in the ratio of 1:2 (28%).
    Matched MeSH terms: Calcium Compounds
  10. Rozila I, Azari P, Munirah S, Safwani WKZW, Pingguan-Murphy B, Chua KH
    Polymers (Basel), 2021 Feb 17;13(4).
    PMID: 33671175 DOI: 10.3390/polym13040597
    (1) Background: Stem cells in combination with scaffolds and bioactive molecules have made significant contributions to the regeneration of damaged bone tissues. A co-culture system can be effective in enhancing the proliferation rate and osteogenic differentiation of the stem cells. Hence, the aim of this study was to investigate the osteogenic differentiation of human adipose derived stem cells when co-cultured with human osteoblasts and seeded on polycaprolactone (PCL):hydroxyapatite (HA) scaffold; (2) Methods: Human adipose-derived stem cells (ASC) and human osteoblasts (HOB) were seeded in three different ratios of 1:2, 1:2 and 2:1 in the PCL-HA scaffolds. The osteogenic differentiation ability was evaluated based on cell morphology, proliferation rate, alkaline phosphatase (ALP) activity, calcium deposition and osteogenic genes expression levels using quantitative RT-PCR; (3) Results: The co-cultured of ASC/HOB in ratio 2:1 seeded on the PCL-HA scaffolds showed the most positive osteogenic differentiation as compared to other groups, which resulted in higher ALP activity, calcium deposition and osteogenic genes expression, particularly Runx, ALP and BSP. These genes indicate that the co-cultured ASC/HOB seeded on PCL-HA was at the early stage of osteogenic development; (4) Conclusions: The combination of co-culture system (ASC/HOB) and PCL-HA scaffolds promote osteogenic differentiation and early bone formation.
    Matched MeSH terms: Calcium
  11. Ismail IH, Al-Bayaty FH, Yusof EM, Gulam Khan HBS, Hamka FA, Azmi NA
    J Conserv Dent, 2021 02 10;23(5):489-496.
    PMID: 33911359 DOI: 10.4103/JCD.JCD_528_20
    Introduction: Enterococcus faecalis can be found in failed endodontic treatment (FET) even after performing primary endodontic treatment (PET). Calcium hydroxide (Ca(OH)2) cannot fully eliminate this microorganism during PET. Brazilian green propolis (bee glue) was found to be more effective against E. faecalis when compared to Ca(OH)2. A much less studied Malaysian geopropolis (MP) as well as Aloe vera (AV) is antibacterial but is unknown against E. faecalis.

    Objective: The objective of this study is to determine the antimicrobial effects of MP, AV, and MP + AV in comparison with Ca(OH)2 against E. faecalis, as an intracanal medicament.

    Materials and Methods: Antimicrobial activity of MP, AV, MP + AV, Ca(OH)2, and dimethyl sulfoxide was tested against E. faecalis using antimicrobial sensitivity testing, minimum inhibitory concentration (MIC), and minimum bactericidal concentration (MBC). The results were analyzed by Kruskal-Wallis test with Mann-Whitney post hoc test and repeated measures analysis of variance with Bonferroni post hoc test (P < 0.05).

    Results: For agar well-diffusion method, MP + AV gave maximum inhibition zone diameter (mean: 8.11 ± 0.015 mm), MP (mean: 6.21 ± 0.046 mm, Ca(OH)2 (mean: 5.5 ± 0.006), and AV (mean: 5.05 ± 0.012) with P < 0.05. MIC for MP + AV was 2 mg/ml, MP at 8 mg/ml, Ca(OH)2 at 8 mg/ml, and AV at 16 mg/ml. The MBC for MP + AV is at 4 mg/ml, MP at 16 mg/ml, Ca(OH)2 at 16 mg/ml, and AV at 32 mg/ml.

    Conclusion: The combination of MP and AV consistently showed better antimicrobial activity compared to MP and AV alone against E. faecalis. The findings suggest that MP and AV used in combination may be an ideal intracanal medicament in FET and PET.

    Matched MeSH terms: Calcium Hydroxide
  12. Sies NS, Zaini AA, de Bruyne JA, Jalaludin MY, Nathan AM, Han NY, et al.
    Sci Rep, 2021 02 04;11(1):3193.
    PMID: 33542317 DOI: 10.1038/s41598-021-82605-6
    Repetitive hypoxia seen in obstructive sleep apnoea syndrome (OSAS) may affect bone metabolism increasing the risk for secondary osteoporosis. This study investigates the association between OSAS in children and secondary osteoporosis. This cross-sectional study included 150 children aged 10-17 years: 86 with OSAS and 64 with no OSAS. OSAS was confirmed by polysomnography. Quantitative ultrasound (QUS) of calcaneum measuring speed of sound (SoS) and broadband ultrasound attenuation (BUA) were collected. Other parameters collected including bone profile, vitamin D levels, physical activity scoring and dietary calcium intake. Majority were male and Malay ethnicity. OSAS children were mostly obese (84%) and 57% had moderate to severe OSAS. Most had lower physical activities scores. Mean (SD) phosphate and Alkaline phosphatase were lower in OSA children compared to controls: PO4, p = 0.039 and ALP, p 
    Matched MeSH terms: Calcium, Dietary/administration & dosage; Calcium, Dietary/blood
  13. Angelopoulou E, Paudel YN, Piperi C
    Cell Mol Life Sci, 2021 Feb;78(4):1445-1453.
    PMID: 33052436 DOI: 10.1007/s00018-020-03673-x
    The exact etiology of Parkinson's disease (PD) remains obscure, lacking effective diagnostic and prognostic biomarkers. In search of novel molecular factors that may contribute to PD pathogenesis, emerging evidence highlights the multifunctional role of the calcium-binding protein S100B that is widely expressed in the brain and predominantly in astrocytes. Preclinical evidence points towards the possible time-specific contributing role of S100B in the pathogenesis of neurodegenerative disorders including PD, mainly by regulating neuroinflammation and dopamine metabolism. Although existing clinical evidence presents some contradictions, estimation of S100B in the serum and cerebrospinal fluid seems to hold a great promise as a potential PD biomarker, particularly regarding the severity of motor and non-motor PD symptoms. Furthermore, given the recent development of S100B inhibitors that are able to cross the blood brain barrier, novel opportunities are arising in the research field of PD therapeutics. In this review, we provide an update on recent advances in the implication of S100B protein in the pathogenesis of PD and discuss relevant studies investigating the biomarker potential of S100B in PD, aiming to shed more light on clinical targeting approaches related to this incurable disorder.
    Matched MeSH terms: S100 Calcium Binding Protein beta Subunit/genetics*
  14. Veettil SK, Wong TY, Loo YS, Playdon MC, Lai NM, Giovannucci EL, et al.
    JAMA Netw Open, 2021 02 01;4(2):e2037341.
    PMID: 33591366 DOI: 10.1001/jamanetworkopen.2020.37341
    Importance: Several meta-analyses have summarized evidence for the association between dietary factors and the incidence of colorectal cancer (CRC). However, to date, there has been little synthesis of the strength, precision, and quality of this evidence in aggregate.

    Objective: To grade the evidence from published meta-analyses of prospective observational studies that assessed the association of dietary patterns, specific foods, food groups, beverages (including alcohol), macronutrients, and micronutrients with the incidence of CRC.

    Data Sources: MEDLINE, Embase, and the Cochrane Library were searched from database inception to September 2019.

    Evidence Review: Only meta-analyses of prospective observational studies with a cohort study design were eligible. Evidence of association was graded according to established criteria as follows: convincing, highly suggestive, suggestive, weak, or not significant.

    Results: From 9954 publications, 222 full-text articles (2.2%) were evaluated for eligibility, and 45 meta-analyses (20.3%) that described 109 associations between dietary factors and CRC incidence were selected. Overall, 35 of the 109 associations (32.1%) were nominally statistically significant using random-effects meta-analysis models; 17 associations (15.6%) demonstrated large heterogeneity between studies (I2 > 50%), whereas small-study effects were found for 11 associations (10.1%). Excess significance bias was not detected for any association between diet and CRC. The primary analysis identified 5 (4.6%) convincing, 2 (1.8%) highly suggestive, 10 (9.2%) suggestive, and 18 (16.5%) weak associations between diet and CRC, while there was no evidence for 74 (67.9%) associations. There was convincing evidence of an association of intake of red meat (high vs low) and alcohol (≥4 drinks/d vs 0 or occasional drinks) with the incidence of CRC and an inverse association of higher vs lower intakes of dietary fiber, calcium, and yogurt with CRC risk. The evidence for convincing associations remained robust following sensitivity analyses.

    Conclusions and Relevance: This umbrella review found convincing evidence of an association between lower CRC risk and higher intakes of dietary fiber, dietary calcium, and yogurt and lower intakes of alcohol and red meat. More research is needed on specific foods for which evidence remains suggestive, including other dairy products, whole grains, processed meat, and specific dietary patterns.

    Matched MeSH terms: Calcium, Dietary*
  15. Chenna D, Shastry S, Das S
    Malays J Med Sci, 2021 Feb;28(1):35-40.
    PMID: 33679218 DOI: 10.21315/mjms2021.28.1.5
    Background: Biomaterials containing platelets have been used to promote healing of ulcers and burns, as well as in implantology and maxillofacial and plastic surgery to achieve wound healing and tissue repair. Commercial devices to prepare autologous biomaterials involve diverse preparation methods that can have high production costs and low yields. Hence, we designed a protocol for preparation of large amounts of autologous platelet-rich fibrin (PRF) glue using conventional processing techniques for blood components.

    Methods: Autologous whole blood collected 72 h before surgery was processed to prepare platelet concentrates and cryoprecipitate. In a closed system, calcium was added to the cryoprecipitate to release autologous thrombin and generate a firm fibrin clot. The fibrin clot, platelets and calcium were then placed in a conical flask in which a PRF glue formed. The protocol was validated through determination of pre- and post-platelet counts and fibrinogen amounts in the product.

    Results: Platelets were recovered with 68% efficiency during the preparation. Essentially no platelets or fibrinogen were found in the supernatant of the PRF glue, suggesting that nearly all had been incorporated in a PRF glue having a relatively large (8 cm × 10 cm) size.

    Conclusion: The protocol described here is a cost-effective, simple and closed system that can be used to produce large-size PRF glue to promote repair of major surgical defects.

    Matched MeSH terms: Calcium, Dietary
  16. Senik MH, Abu IF, Fadhullah W
    Malays J Med Sci, 2021 Feb;28(1):15-26.
    PMID: 33679216 DOI: 10.21315/mjms2021.28.1.3
    Background: Kainic acid (KA)-induced seizures may be a valuable tool in the assessment of anti-epileptic drug efficacy in complex partial seizures. This study investigated the effects of KA on ATP-sensitive K+ (KATP) channels opening probability (NPo), which plays a crucial role in neuronal activities.

    Methods: For the optimisation and validation protocol, β-cells were plated onto 35 mm plastic petri dishes and maintained in RPMI-1640 media supplemented with 10 mM glucose, 10% FCS and 25 mM of N-2-hydroxyethylpiperazine-N-ethanesulfonic acid (HEPES). The treatment effects of 10 mM glucose and 30 μM fluoxetine on KATP channels NPo of β-cells were assessed via cell-attached patch-clamp recordings. For hippocampus cell experiments, hippocampi were harvested from day 17 of maternal Lister-hooded rat foetus, and then transferred to a Ca2+ and Mg2+-free HEPES-buffered Hank's salt solution (HHSS). The dissociated cells were cultured and plated onto a 25 mm round cover glasses coated with poly-d-lysine (0.1 mg/mL) in a petri dish. The KATP channels NPo of hippocampus cells when perfused with 1 mM and 10 mM of KA were determined.

    Results: NPo of β-cells showed significant decreasing patterns (P < 0.001) when treated with 10 mM glucose 0.048 (0.027) as well as 30 μM fluoxetine 0.190 (0.141) as compared to basal counterpart. In hippocampus cell experiment, a significant increase (P < 0.001) in mean NPo 2.148 (0.175) of neurons when applied with 1 mM of KA as compared to basal was observed.

    Conclusion: The two concentrations of KA used in the study exerted contrasting effects toward the mean of NPo. It is hypothesised that KA at lower concentration (1 mM) opens more KATP channels, leading to hyperpolarisation of the neurons, which may prevent neuronal hyper excitability. No effect was shown in 10 mM KA treatment, suggesting that only lower than 10 mM KA produced significant changes in KATP channels. This implies further validation of KA concentration to be used in the future.

    Matched MeSH terms: Calcium
  17. Mallikarjuna K, Nasif O, Ali Alharbi S, Chinni SV, Reddy LV, Reddy MRV, et al.
    Biomolecules, 2021 01 29;11(2).
    PMID: 33572968 DOI: 10.3390/biom11020190
    Continuously increasing energy demand and growing concern about energy resources has attracted much research in the field of clean and sustainable energy sources. In this context, zero-emission fuels are required for energy production to reduce the usage of fossil fuel resources. Here, we present the synthesis of Pd-Ag-decorated reduced graphene oxide (rGO) nanostructures using a green chemical approach with stevia extract for hydrogen production and antibacterial studies under light irradiation. Moreover, bimetallic nanostructures are potentially lime lighted due to their synergetic effect in both scientific and technical aspects. Structural characteristics such as crystal structure and morphological features of the synthesized nanostructures were analyzed using X-ray diffraction and transmission electron microscopy. Analysis of elemental composition and oxidation states was carried out by X-ray photoelectron spectroscopy. Optical characteristics of the biosynthesized nanostructures were obtained by UV-Vis absorption spectroscopy, and Fourier transform infrared spectroscopy was used to investigate possible functional groups that act as reducing and capping agents. The antimicrobial activity of the biosynthesized Pd-Ag-decorated rGO nanostructures was excellent, inactivating 96% of Escherichia coli cells during experiments over 150 min under visible light irradiation. Hence, these biosynthesized Pd-Ag-decorated rGO nanostructures can be utilized for alternative nanomaterial-based drug development in the future.
    Matched MeSH terms: Calcium Compounds
  18. Phang MWL, Lew SY, Chung I, Lim WK, Lim LW, Wong KH
    Chin Med, 2021 Jan 28;16(1):15.
    PMID: 33509239 DOI: 10.1186/s13020-020-00414-x
    BACKGROUND: Hereditary ataxia (HA) represents a group of genetically heterogeneous neurodegenerative diseases caused by dysfunction of the cerebellum or disruption of the connection between the cerebellum and other areas of the central nervous system. Phenotypic manifestation of HA includes unsteadiness of stance and gait, dysarthria, nystagmus, dysmetria and complaints of clumsiness. There are no specific treatments for HA. Management strategies provide supportive treatment to reduce symptoms.

    OBJECTIVES: This systematic review aimed to identify, evaluate and summarise the published literature on the therapeutic roles of natural remedies in the treatment of HA to provide evidence for clinical practice.

    METHODS: A systematic literature search was conducted using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Web of Science, PubMed and Science Direct Scopus were thoroughly searched for relevant published articles from June 2007 to July 2020.

    RESULTS: Ten pre-clinical and two clinical studies were eligible for inclusion in this systematic review. We identified the therapeutic roles of medicinal plants Brassica napus, Gardenia jasminoides, Gastrodia elata, Ginkgo biloba, Glycyrrhiza inflata, Paeonia lactiflora, Pueraria lobata and Rehmannia glutinosa; herbal formulations Shaoyao Gancao Tang and Zhengan Xifeng Tang; and medicinal mushroom Hericium erinaceus in the treatment of HA. In this review, we evaluated the mode of actions contributing to their therapeutic effects, including activation of the ubiquitin-proteasome system, activation of antioxidant pathways, maintenance of intracellular calcium homeostasis and regulation of chaperones. We also briefly highlighted the integral cellular signalling pathways responsible for orchestrating the mode of actions.

    CONCLUSION: We reviewed the therapeutic roles of natural remedies in improving or halting the progression of HA, which warrant further study for applications into clinical practice.

    Matched MeSH terms: Calcium
  19. Mondal AK, Mohamed MA, Ping LK, Mohamad Taib MF, Samat MH, Mohammad Haniff MAS, et al.
    Materials (Basel), 2021 Jan 28;14(3).
    PMID: 33525586 DOI: 10.3390/ma14030604
    Gallium oxide (Ga2O3) is a promising wide-band-gap semiconductor material for UV optical detectors and high-power transistor applications. The fabrication of p-type Ga2O3 is a key problem that hinders its potential for realistic power applications. In this paper, pure α-Ga2O3 and Ca-doped α-Ga2O3 band structure, the density of states, charge density distribution, and optical properties were determined by a first-principles generalized gradient approximation plane-wave pseudopotential method based on density functional theory. It was found that calcium (Ca) doping decreases the bandgap by introducing deep acceptor energy levels as the intermediate band above the valence band maximum. This intermediate valence band mainly consists of Ca 3p and O 2p orbitals and is adequately high in energy to provide an opportunity for p-type conductivity. Moreover, Ca doping enhances the absorptivity and reflectivity become low in the visible region. Aside, transparency decreases compared to the pure material. The optical properties were studied and clarified by electrons-photons interband transitions along with the complex dielectric function's imaginary function.
    Matched MeSH terms: Calcium, Dietary
  20. Hisham NAN, Zaid MHM, Aziz SHA, Muhammad FD
    Materials (Basel), 2021 Jan 26;14(3).
    PMID: 33530370 DOI: 10.3390/ma14030570
    Soda lime silica (SLS) waste as the source of silica (SiO2) and ark clamshell (ACS) as the foaming agent has been utilized to fabricate the low-cost and lightweight foam glass-ceramics. A series of 1 and 6 wt% foam glass-ceramics were successfully prepared by the conventional solid-state sintering method at various sintering temperatures for 60 min. The bulk density of the samples has achieved minimum density (1.014 g/cm3) with maximum expansion (62.31%) at 6 wt% of the ACS content sintered at 800 °C for 60 min. The bulk density increases while the linear shrinkage and total porosity decrease with the progression of ACS contents and sintering temperature, where the results correspond with the FESEM micrograph. The result of XRD and FTIR transmittance spectra have shown that the formation of wollastonite crystal has occurred starting at 6 wt% of the ACS content sintered at 800 °C for 30 min. The highest mechanical performance (3.90 MPa) with an average total porosity (8.04%) is observed for the sample containing 1 wt% of ACS. It can be concluded that the composition of foam glass-ceramics (1 and 6 wt%) and sintering temperatures give significant results to the structural, physical, and mechanical properties of the fabricated foam glass-ceramics.
    Matched MeSH terms: Calcium Compounds
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