Iso-mukaadial acetate and ursolic acid acetate bind to Plasmodium Falciparum heat shock protein 70: towards targeting parasite protein folding pathway.

Plasmodium falciparum is the most lethal malaria parasite. P. falciparum Hsp70 (PfHsp70) is an essential molecular chaperone (facilitates protein folding) and is deemed a prospective antimalarial drug target. The present study investigates the binding capabilities of select plant derivatives, iso-mukaadial acetate (IMA) and ursolic acid acetate (UAA), against P. falciparum using an in silico docking approach. The interaction between the ligands and PfHsp70 was evaluated using plasmon resonance (SPR) analysis. Molecular docking, binding free energy analysis and molecular dynamics simulations were conducted towards understanding the mechanisms by which the compounds bind to PfHsp70. The molecular docking results revealed ligand flexibilities, conformations and positions of key amino acid residues and protein-ligand interactions as crucial factors accounting for selective inhibition of Hsp70. The simulation results also suggest protein-ligand van der Waals forces as the driving force guiding the interaction of these compounds with PfHsp70. Of the two compounds, UAA and IMA bound to PfHsp70 within the micromolar range based on surface plasmon resonance (SPR) based binding assay. Our findings pave way for future rational design of new selective compounds targeting PfHsp70.

Interfacial Electronic States of GeC/g-C3N4 van der Waal Heterostructure with Promising Photocatalytic Activity via Hydrogenation.

The bandgap of most known two-dimensional materials can be tuned by hydrogenation, although certain 2D materials lack a sufficient wide bandgap. Currently, it would be perfect to design non-toxic, low-cost, and high-performance photocatalysts for photocatalytic water splitting via hydrogenation. We systematically examine the impact of hydrogenation on the optical and electronic characteristics of GeC/g-C3N4 vdW heterostructures (vdWHs) with four different stacking patterns using first-principles calculations. The phonon spectra, interlayer distance, binding energies and ab initio molecular dynamics calculations show the kinetic, mechanical, and thermal stability of GeC/g-C3N4 vdWH after hydrogenation at 300, 500 and 800 K and possesses anisotropic Poisson's ratio, Young's and bulk modulus, suggesting that it's a promising candidate for experimental fabrication. According to an investigation of its electronic properties, GeC/g-C3N4 vdWH has a bandgap of 1.28 eV, but hydrogenation dramatically increases it to 2.47 eV. As a result of interface-induced electronic doping, the electronic states in g-C3N4 might be significantly adjusted by coming into contact with hydrogenated GeC sheets. The vdWH exhibits a type-II semiconductor, which can enhance the spatial separation of electron-hole pairs and has a strong red-shift of absorption coefficient than those of the constituent monolayers. The high potential drop caused by the significant valence and conduction band offsets effectively separated the charge carriers. The absorption coefficient of GeCH2/g-C3N4 vdWH is highly influenced by a biaxial compressive strain more than the biaxial tensile strain. Our theoretical research implies that the hydrogenated GeCH2/g-C3N4 vdWH possesses tunable optical and electronic behaviour for use as a hole-transport material in solar energy harvesting, nanoelectronic and optoelectronic devices.

Assessment of irrigation water quality for vegetable farming in peri-urban Kumasi.

Polluted water contains a variety of toxic compounds that tend to affect human health. Farmers have recently looked at runoff wastewater as a source of irrigation water because it comes at no cost and is a more efficient alternative to potable water due to the high demand but limited supply. This present study assesses the quality and suitability of water sources used for irrigation at the Kwame Nkrumah University of Science and Technology vegetable farmlands. The study specifically investigated the quality of water used for irrigation with the following parameters: pH, turbidity, total dissolved solids, total suspended solids, chloride, chemical oxygen demand, biological oxygen demand, oil and grease, fluoride, nitrate, nitrite, sulphate, sodium, calcium, magnesium, sodium adsorption potential, alkalinity, conductivity, phosphate, Escherichia coli, fecal and total coliforms. The results revealed that the water contained moderate levels of chloride and could be good for plant growth. The total coliform counts range from 2.1 × 106 to 4.15 × 107 MPN/100 mL, suggesting a relatively high microbial load in the irrigation water. The results also suggested that the sodium absorption ratio was very low and may not affect the quality of water for irrigation purposes. Fe levels far exceed the 5 mg/L maximum acceptable limits recommended by the WHO and FAO for the irrigation of vegetables. The high Fe concentration could discolor the leaves of some plants, especially foliage leaves. However, the levels of Cd were within the WHO maximum permissible limit of 0.01 mg/L.

Exposure and health risk assessment of transition metals in rice found on the Ghanaian market.

This study investigates the concentration of transition metals in imported and local rice brands on sale in some Ghanaian markets and the biochemical influences on the health of the Ghanaian population. A comparative analysis with previous studies in Ghana reveals that levels of Fe (3.64-4.44 mg/kg), Cd (0.03 mg/kg) and Cu (14.07-38.13 mg/kg) in the current study are much lower than the 13.67-21.35, 1.67-3.01, and 14.07-38.13 mg/kg recorded for Fe, Cd, and Cu, respectively. Rice sold in the Ghanaian markets contained different transition metals of which some are essential (Zn, Cu, Mn, and Fe). The levels of transition metals, such as Mn, Zn, Cd, Cu, and Fe are in moderate concentrations, which are well within the maximum acceptable limit of the World Health Organization. This study has revealed that R5 and R9 from the USA and India, respectively, recorded hazard indices above the safe limit of 1 and can therefore have the potential to pose detrimental health complications to consumers in the long term.

Potential health risk and bio-accessibility of metal and minerals in saltpetre (a food additive).

Food additives are used to enhance freshness, safety, appearance, flavour, and texture of food. Depending on the absorbed dose, exposure method, and length of exposure, heavy metals in diet may have a negative impact on human health. The X-Ray Fluorescence (XRF) Analyzer from Niton Thermo Scientific (Mobile Test S, NDTr-XL3t-86956, com 24) was used in this work to measure the heavy metal content in saltpetre, a food additive that mostly contains potassium nitrate. The average essential metal concentrations in the samples were determined to be 27044.27 ± 10905.18 mg kg-1, 24521.10 ± 6564.28 mg kg-1, 2418.33 ± 461.50 mg kg-1, and 4.615 ± 3.59 mg kg-1 for Ca, K, Fe and Zn respectively. Toxic metals (As, Pb) were present in the saltpetre samples at 4.13 ± 2.47 mg kg-1 and 2.11 ± 1.87 mg kg-1 average concentrations. No traces of mercury or cadmium were detected. Studies on exposure, health risks, and bio-accessibility identified arsenic as a significant risk factor for potential illnesses. The need to monitor heavy metal content of saltpetre and any potential health effects on consumers is brought to light by this study.

Boosting the photocatalytic H2 evolution activity of type-II g-GaN/Sc2CO2 van der Waals heterostructure using applied biaxial strain and external electric field.

Two-dimensional (2D) van der Waals (vdW) heterostructures are a new class of materials with highly tunable bandgap transition type, bandgap energy and band alignment. Herein, we have designed a novel 2D g-GaN/Sc2CO2 heterostructure as a potential solar-driven photocatalyst for the water splitting process and investigate its catalytic stability, interfacial interactions, and optical and electronic properties, as well as the effects of applying an electric field and biaxial strain using first-principles calculation. The calculated lattice mismatch and binding energy showed that g-GaN and Sc2CO2 are in contact and may form a stable vdW heterostructure. Ab initio molecular dynamics and phonon dispersion simulations show thermal and dynamic stability. g-GaN/Sc2CO2 has an indirect bandgap energy with appropriate type-II band alignment relative to the water redox potentials. Meanwhile, the interfacial charge transfer from g-GaN to Sc2CO2 can effectively separate electron-hole pairs. Moreover, a potential drop of 3.78 eV is observed across the interface, inducing a built-in electric field pointing from g-GaN to Sc2CO2. The heterostructure shows improved visible-light optical absorption compared to the isolated g-GaN and Sc2CO2 monolayers. Our study demonstrates that tunable electronic and structural properties can be realised in the g-GaN/Sc2CO2 heterostructure by varying the electric field and biaxial strain. In particular, the compressive strain and negative electric field are more effective for promoting hydrogen production performance. Since it is challenging to tune the electric field and biaxial strain experimentally, our research provides strategies to boost the performance of MXene-based heterojunction photocatalysts in solar harvesting and optoelectronic devices.

Mineral and proximate composition of the meat and shell of three snail species.

Meat is a vital source of nutrients for human wellbeing and health; however, recent studies suggest a decline in meat preference as a protein source due to some health problems associated with meat intake. This study evaluates the levels of essential elements (Mn, Mg, P, Ca, K, Cu, Na, Zn and Fe) and proximate composition (protein, fat, moisture, carbohydrate, fibre and ash) of three snail species namely; Achatina achatina, Achatina fulica and Archachatina marginata species from the Kumasi Central Market. The mineral content and proximate composition of the three land snail species' shell and meat were analysed using Atomic Absorption Spectrometry and other Standard Methods of Analysis. The study revealed that the three snail species differed in the composition of significant nutrients and trace elements in meat. It is evident from this study that the consumption of snail meat can promote good human health, with Archachatina marginata having the best nutritional value. In the meat from the three snail species, a strong significant positive correlation between Ca and P levels was observed, and the Cu and Fe (p < 0.05). In both the proximate and mineral analysis, each meat parameter was correspondingly higher than that of the shell for all the snail species, except for ash and Ca contents. The estimated daily intakes of Zn, Fe, Mn and Cu were lower compared with the tolerable daily intake, suggesting that the essential elements are at acceptable levels. Therefore, consumers of these land snails will gain the benefits of the proximate and mineral constituents. The shells can also be utilised as food supplements for livestock and eliminate the burden of managing snail shell waste.

Expression profile of tumour suppressor protein p53 and its regulator MDM2 in a cohort of breast cancer patients in a Tertiary Hospital in Ghana.

BACKGROUND: Inactivation or mutation of the tumour suppressor gene p53 or its regulator mouse double minute 2 (MDM2) is the commonest event in breast cancer. These altered genes usually express abnormally high levels of their proteins in many carcinomas. The phenotypic expression of p53 and MDM2 in breast cancer cases in our setting is not known. This study investigated the expression of the tumour suppressor protein p53 and its regulator MDM2, using immunohistochemistry in a Ghana breast cancer cohort. METHOD: A 9-year retrospective cross-sectional study on archived tissue blocks-formalin fixed paraffin embedded tissue (FFPE) was carried out. Demographic data were abstracted. Based on complete clinical data and availability of FFPE archived blocks 203 cases were selected for tissue micro array (TMA) construction. The TMA sections were subjected to immunohistochemistry (IHC) (ER, PR, HER2, p53, and MDM2). Expression of p53 and MDM2 were related to grade and molecular subtypes. RESULTS: The age ranged from 17 to 92 years (mean = 49.34 ± 13.74). Most of the cases were high grade; grade II (34.9%) and grade III (55.7%). Fifty-four percent of the cases were triple negative. Invasive ductal carcinoma no special type was the commonest histotype (87.1%). Thirty-six percent (36%) of the cases expressed p53. Significant associations were found between p53 overexpression and histological grade (p = 0.034), triple negative (p = 0.0333) and luminal B (p<0.01) tumors. Most cases (93.1%) were negative for MDM2 expression. Significant association was found between MDM2 and HER2 over-expression as well as Ki-67. There was no significant positive correlation between MDM2 and p53 co-expression (p>0.05). CONCLUSION: The elevated level of p53 expression in the aggressive breast cancer phenotypes (high histological grade and triple negative) in our cohort suggest that P53 elevation may be a poor prognostic marker in our setting. High expression of MDM2 in our cohort with high Ki67; also in cases with Her2/neu overexpression known with predictable poor prognosis in the absence of target therapy suggest MDM2 may be associated with aggressive biological behaviour in our breast cancer cases. The non-significant association of p53 and MDM2 expression in the same cases as also documented by previous studies suggest independent genetic pathway in tumourigenesis.

The Analysis of bcl-2 in Association with p53 and Ki-67 in Triple Negative Breast Cancer and Other Molecular Subtypes in Ghana.

BACKGROUND: Little is known about the role of apoptosis in the tumorigenesis and prognosis of breast cancer in Ghana. Chemotherapeutic drug efficacy partially relates to apoptosis induction, rendering it a vital target in cancer therapy with unique biomarker opportunities that have not been exploited. Aberrations in this pathway are central to tumorigenesis, tumor progression, overall tumor growth, and regression during treatment therapies. Antiapoptotic bcl-2 (gene) and p53 are known to play roles in apoptosis while Ki-67 is a proliferative marker. The aim of our study is to determine the association of bcl-2 (protein) with p53 and Ki-67 in 203 consecutive breast cancer cases over a 10-year period. METHOD: A retrospective cross-sectional study on archival FFPE tissue blocks over a 9-year period with abstraction of clinicopathologic data. Two hundred and three consecutive and suitable FFPE blocks were selected for tissue microarray (TMA) construction, and IHC (bcl-2 (protein), Ki-67, p53, cyclin D, pan cytokeratins A and E, ER, PR, and HER2/neu) was done. Expressions of bcl-2 (protein), p53, and Ki-67 were related to histological grade, lymphovascular invasion, and molecular subtypes. SPSS version 23 was used to analyze results. RESULTS: Most of our cases were in the fifth decade of life (31%); invasive carcinoma of no special type (NST) was predominant (87%); histological grade III (38%) was the highest; and Luminal A (19.8%), Luminal B (9.9%), HER2 (16%), and TNBC (54.3%) constituted the molecular classes. bcl-2 expression was found in 38% of the cases. Our cases also showed mutation in p53 (36.7%) and ki-67 expression (62.5%). bcl-2 (protein) and p53 significantly correlated with Luminal B and TNBC (p < 0.01). Ki-67 also correlated significantly with Luminal A and B and HER2 overexpression (p < 0.01). Premenopausal age (40-49) and histological grade inversely correlated with bcl-2 (protein) expression. p53 statistically correlated with Ki-67 (p < 0.05). CONCLUSION: Our results show high expression of bcl-2 (protein) suggesting an important role of apoptosis in Ghanaian breast cancer cases. bcl-2 (protein), p53, and Ki-67 expressions emerged interdependently from this research and can thus be manipulated in prediction and prognosis of breast cancers in our setting.

Developing a simple box-behnken experimental design on the removal of doxorubicin anticancer drug using Fe3O4/graphene nanoribbons adsorbent.

This paper aims to develop a Box-Behnken experimental design system to optimize the removal process of doxorubicin anticancer drugs. For this goal, Fe3O4/graphene nanoribbons was selected as adsorbent and removal of doxorubicin anticancer drug optimized using Box-Behnken experimental design with a selection of four effective factors. A three-level, four-factor Box-Behnken experimental design was used to assess the relationship between removal percentage as a dependent variable with adsorption weight (0.0015-0.01 mg), pH (3-9), temperature (15-45 °C) and time (1-15 min) as independent variables. Optimized condition by Behnken experimental design (pH = 7.36; time = 15 min; adsorbent weight = 0.01 mg and temperature = 29.26 °C) improved removal of doxorubicin anticancer drug about 99.2% in aqueous solution. The dynamic behavior, adsorption properties and mechanism of doxorubicin molecule on Fe3O4/graphene nanoribbon were investigated based on ab initio molecular dynamics (AIMD) simulations and density functional theory calculations with dispersion corrections. A closer inspection of the adsorption configurations and binding energies revealed that π-π interactions were the driving force when the doxorubicin molecule adsorbed on Fe3O4/graphene nanoribbon. The observed negative adsorption energy signifies a favourable and exothermic adsorption process of the various adsorbate-substrate systems. Besides, AIMD and phonon dispersion calculations confirm the dynamic stability of Fe3O4/graphene nanoribbon.

SF6 decomposed gas sensing performance of van der Waals layered cobalt oxyhydroxide: insights from a computational study.

The detection of SF6 decomposition products plays a significant part in identifying and assessing the electric discharge faults in SF6 insulation equipment. We performed dispersion corrected density functional theory calculations to study the adsorption performance of CoOOH upon SO2, SF4, SOF2, CF4, and SO2F2 toxic gases, to investigate their potential application as a gas sensor. The results clearly show a weak force between the CoOOH sheet, and the molecular gas with moderate adsorption strength enhances the desorption processes. According to Löwdin charge population analysis, electrons transfer from the molecular gas to the CoOOH surface, where the molecular gas behaves like an electron donor. The lower bandgap energy of the adsorption systems compared with pristine CoOOH significantly increases its electrical conductivity and gas sensing performance. The higher charge transfer and adsorption energy of the SOF2 adsorption system compared with the other four molecular gas is due to orbital hybridization around the Fermi energy. The theoretical computed adsorption energy with ultrahigh sensitivity and fast recovery time suggests that SF6 decomposed gases reusability is achieved with CoOOH as a resistance-type gas sensor.

Electro-catalytic amplified sensor for determination of N-acetylcysteine in the presence of theophylline confirmed by experimental coupled theoretical investigation.

The 1,l/-bis(2-phenylethan-1-ol)ferrocene, 1-butyl-3-methylimidazolium hexafluoro phosphate (BMPF6) and NiO-SWCNTs were used to modify carbon paste electrode (BPOFc/BMPF6/NiO-SWCNTs/CPE), which could act as an electro-catalytic tool for the analysis of N-acetylcysteine in this work. The BPOFc/BMPF6/NiO-SWCNTs/CPE with high electrical conductivity showed two completely separate signals with oxidation potentials of 432 and 970 mV for the first time that is sufficient for the determination of N-acetylcysteine in the presence of theophylline. The BPOFc/BMPF6/NiO-SWCNTs/CPE showed linear dynamic ranges of 0.02-300.0 µM and 1.0-350.0 µM with the detection limit of ~ 8.0 nM and 0.6 µM for the measurement of N-acetylcysteine and theophylline, respectively. In the second part, understanding the nature of interaction, quantum conductance modulation, electronic properties, charge density, and adsorption behavior of N-acetylcysteine on NiO-SWCNTs surface from first-principle studies through the use of theoretical investigation is vital for designing high-performance sensor materials. The N-acetylcysteine molecule was chemisorbed on the NiO-SWCNTs surface by suitable adsorption energies (- 1.102 to - 5.042 eV) and reasonable charge transfer between N-acetylcysteine and NiO-SWCNTs.

COVID-19 and stroke: Experience in a Ghanaian healthcare system.

BACKGROUND: The novel coronavirus disease 19 (COVID-19) causes multi-system disease including possibly heightened stroke risk. Data from high-income countries (HIC) suggest disruptions to care delivery with reduced stroke admissions and administration of acute stroke reperfusion therapies. We are unaware of any published data on the impact of the COVID-19 pandemic on stroke admissions and outcomes in sub-Saharan Africa. PURPOSE: To compare rates of stroke admissions and case fatality between corresponding periods in 2020 and 2019, within a hospital system in Ghana, to assess the potential impact of the COVID-19 pandemic. METHODS: We compared monthly stroke admissions and mortality rates between January to June 2020 vs. January to June 2019 at the Komfo Anokye Teaching Hospital, a tertiary medical center in Ghana. Predictors of in-patient mortality were assessed using a multivariate logistic regression model. RESULTS: Stroke admissions were higher in January to June 2020 vs. January to June 2019 (431 vs. 401), an increase of +7.5% (95% CI: 5.1-10.5%). There was also a rise in recurrent stroke admissions in 2020 vs. 2019 (19.0% vs. 10.9%, p = .0026). Stroke case fatality trended higher in 2020 vs. 2019 (29.3% vs. 24.2%, p = .095) with an adjusted odds ratio of 1.22 (95% CI: 0.89-1.68). CONCLUSION: While an influence of secular trends cannot be excluded, the COVID-19 outbreak coincided with a comparatively significant rise in initial and recurrent stroke admissions at this Ghanaian tertiary hospital. Continued surveillance at this hospital, as well as assessment of this issue at other sites in Africa is warranted.

Highly Selective and Sensitive Detection of Formaldehyde by ß12-Borophene/SnO2 Heterostructures: The Role of an External Electric Field and In-Plain Biaxial Strain.

The design of sensors for detecting formaldehyde (HCHO) gas in the environment is vastly necessary since even at low concentrations, it is very harmful to human health. Herein, a novel, reproductive, selective, and sensitive HCHO sensor has been designed by functionalizing SnO2 with ß12-borophene sheets for the first time via density functional theory calculations. The results revealed that the wide direct band-gap SnO2 semiconductor and zero-band-gap ß12-borophene form a distinctive orbital hybridization heterostructure with a moderate direct band gap of 1.09 eV and effectively enhance the electrical conductivity, selectivity, long-term stability, and the HCHO molecule response. The HCHO molecule chemisorbs in several orientations on the ß12-borophene/SnO2 surface, behaving as a charge acceptor and donor at some point. Moreover, applied biaxial strain and external electric field enhance the stability, band gap, and charge transfer of the adsorbent-adsorbate interactions. Therefore, a ß12-borophene/SnO2 sensor with excellent adsorption, work function, tunable band gaps, charge redistributions, and sensing properties can be applied in indoor pollution detection and optoelectronic applications, where an external electric field can be used.

Composite 2D Nanointerfaces for Electrochemical Biosensing: An Experimental and Theoretical Study.

In this study, composite two-dimensional (2D) materials consisting of graphene (Gr) and tungsten disulfide (WS2) were coalesced with gold nanoparticles (AuNPs) through a self-assembly process to boost the conductivity of the resulting graphene-tungsten disulfide-gold nanoparticles (Gr-WS2-AuNPs) nanointerface structure. Structural and morphological characterization of the nanohybrid structure reveals crystalline thin flakelike agglomerates. Electrochemical characterization reveals an excellent electron transfer process for all the modified electrodes at the interface. The Gr/WS2/AuNPs/HRP/GCE modified bioelectrode exhibited a rapid electrobiocatalytic response in detecting H2O2 and a linear response from 0.40 to 23 mM, while 11.07 µA/mM/cm2 is the sensitivity value. This shows that the fabricated Gr/WS2/AuNPs/HRP interface structure is an excellent material for future developments in electrochemical biosensing and bioelectronics applications. The interactions, geometry, and energetic and electronic properties of H2O2 adsorption onto Gr/WS2/Au using the density functional theory (DFT) method have also been investigated along with the Grimme's DFT-D3 dispersion method. Different adsorption modes of the H2O2 molecule onto the Gr/WS2/Au surface were considered. In almost all the cases, the adsorption was found to be energetically favorable and chemisorbed, with energies ranging from -2.198 to -3.782 eV. It was found that the W 5d, S 3p, and Au 6s orbitals play a vital role in the adsorption process. The H2O2 adsorption on Gr/WS2/Au remarkably decreases its work function, thereby increasing the field electron emission from the H2O2 molecule to Gr/WS2/Au.

Evaluating Iso-Mukaadial Acetate and Ursolic Acid Acetate as Plasmodium falciparum Hypoxanthine-Guanine-Xanthine Phosphoribosyltransferase Inhibitors.

To date, Plasmodium falciparum is one of the most lethal strains of the malaria parasite. P. falciparum lacks the required enzymes to create its own purines via the de novo pathway, thereby making Plasmodium falciparum hypoxanthine-guanine-xanthine phosphoribosyltransferase (PfHGXPT) a crucial enzyme in the malaria life cycle. Recently, studies have described iso-mukaadial acetate and ursolic acid acetate as promising antimalarials. However, the mode of action is still unknown, thus, the current study sought to investigate the selective inhibitory and binding actions of iso-mukaadial acetate and ursolic acid acetate against recombinant PfHGXPT using in-silico and experimental approaches. Recombinant PfHGXPT protein was expressed using E. coli BL21 cells and homogeneously purified by affinity chromatography. Experimentally, iso-mukaadial acetate and ursolic acid acetate, respectively, demonstrated direct inhibitory activity towards PfHGXPT in a dose-dependent manner. The binding affinity of iso-mukaadial acetate and ursolic acid acetate on the PfHGXPT dissociation constant (KD), where it was found that 0.0833 µM and 2.8396 µM, respectively, are indicative of strong binding. The mode of action for the observed antimalarial activity was further established by a molecular docking study. The molecular docking and dynamics simulations show specific interactions and high affinity within the binding pocket of Plasmodium falciparum and human hypoxanthine-guanine phosphoribosyl transferases. The predicted in silico absorption, distribution, metabolism and excretion/toxicity (ADME/T) properties predicted that the iso-mukaadial acetate ligand may follow the criteria for orally active drugs. The theoretical calculation derived from ADME, molecular docking and dynamics provide in-depth information into the structural basis, specific bonding and non-bonding interactions governing the inhibition of malarial. Taken together, these findings provide a basis for the recommendation of iso-mukaadial acetate and ursolic acid acetate as high-affinity ligands and drug candidates against PfHGXPT.

Assessment of Total Mercury in Hair, Urine and Fingernails of Small-Scale Gold Miners in the Amansie West District, Ghana.

BACKGROUND: Mercury (Hg) is a heavy metal that can cause several adverse health effects based on its form (organic, inorganic or elemental), duration and pathway of exposure. Measurement of mercury present in human biological media is often used to assess human exposure to mercury at mining sites. OBJECTIVES: The aim of the present study was to measure the concentrations of total mercury in urine, hair, and fingernails of miners and inhabitants of Amansie West District, Ghana. METHODS: Concentrations of total mercury were measured in sixty-eight miners and twelve non-miners in the study area using cold vapor atomic absorption spectrophotometry with an automatic mercury analyzer (HG 5000). RESULTS: Total mercury in nails and hair of smelter miners was 3.32 ± 0.36 and 6.59 ± 0.01 µg/g, respectively. Total mercury concentrations in hair samples obtained from smelter miners were above the 1 µg/g guideline set by the United States Environmental Protection Agency (USEPA). Moreover, the total mercury concentration in urine samples was 6.97 ± 0.06 µg/L, far below the >25 µg/L level considered to be a high level of mercury contamination. The total mercury accrued by the individuals was not dependent on age, but was positively associated with duration of stay. CONCLUSIONS: Based on the total mercury (THg) levels analyzed in the biological media, artisanal gold mining activities in Amansie West District are on the increase with a potential risk of developing chronic effects. However, the majority of the population, particularly those engaged in artisanal small-scale gold mining, are unmindful of the hazards posed by the use of mercury in mining operations. The results showed that THg in urine, hair, and fingernails more efficiently distinguished mercury exposure in people close to mining and Hg pollution sources than in people living far from the mining sites. Further education on cleaner artisanal gold mining processes could help to minimize the impact of mercury use and exposure on human health and the environment. PARTICIPANT CONSENT: Obtained. ETHICS APPROVAL: This study was approved by the Ghana Environmental Protection Agency and the Ministry of Local Government and Rural Development in Manso Nkwanta. COMPETING INTERESTS: The authors declare no competing financial interests.

Heavy metals concentration and human health risk assessment in seven commercial fish species from Asafo Market, Ghana.

Health risk assessment and heavy metal accumulation were evaluated in the muscles of widely consumed Trachurus trachurus, Lutjanus fulgens, Lutjanus goreensis, Acanthocybium solandri, Pagellus bellottii, Scomber colias and Dentex congoensis fish species in Asafo, Ghana. The fish samples were prepared using a wet digestion method and the heavy metals analysis was performed with the flame atomic absorption spectrophotometer (UNICAM 969). The results revealed that Mn, Cu, Zn, Cd, and Pb concentrations were below the permissible values set by several health institutions. The health risk assessment based on non-carcinogenic and cancer factors effect indicates no adverse health effect of fish intake. The results of heavy metal concentrations showed that different varieties of fish could be safe for human intake and the results are anticipated to create alertness among the local people.

High-Throughput 2D Heteroatom Graphene Bioelectronic Nanosculpture: A Combined Experimental and Theoretical Study.

In this study, chemical vapor deposition-synthesized heteroatom graphene (HGr) bioelectronic interfaces have been developed for ultrafast, all-electronic detection and analysis of molecules by driving them through tiny holes-or atompores-in a thin lattice of the graphene sheet, including the efforts toward facilitating enhanced electrocatalytic and mapping electron transport activities. The presence of chlorine, nitrogen, and oxygen in the crystalline graphitic layers (<7) has been confirmed using Raman spectroscopy, X-ray photoelectron spectroscopy, and high-resolution transmission electron microscopy. We report a swift bioelectrocatalytic response to step-by-step additions of the substrate with the achievement of a steady current within a few seconds. The response limit was 2.07 µM with a dynamic range of sensing from 2.07 µM to 2.97 mM. The electronic properties and adsorption energies of hydroquinone and p-benzophenone molecule adsorption on pristine, O-, N-, and Cl-doped graphene nanosheet surfaces were systematically investigated using first-principles calculations. The results revealed that the adsorption capacity was improved upon doping graphene nanosheets with O, N, and Cl atoms. Hence, Cl-doped graphene nanosheets were shown as a promising adsorbent toward hydroquinone and p-benzophenone detection.