MyMedR

Displaying publications 1101 - 1120 of 9863 in total

Abstract:

Sort:

Observation and explanation of two-dimensional interconversion of oximes with multiple heart-cutting using comprehensive multidimensional gas chromatography

Kulsing C, Nolvachai Y, Wong YF, Glouzman MI, Marriott PJ

J Chromatogr A, 2018 Apr 20;1546:97-105.
PMID: 29548566 DOI: 10.1016/j.chroma.2018.02.035

Real-time interconversion processes produce unconventional peak broadening in gas chromatography (GC), and can be used to generate kinetic and thermodynamic data. In this study, an unusual separation situation in comprehensive two dimensional GC where two dimensional interconversion (i.e. a raised plateau in both first and second dimension, 1D and 2D) was observed in analysis of oxime isomers. This resulted in a characteristic and unusual rectangular peak shape in the two dimensional result. A related theoretical approach was introduced to explain the peak shape supported by simulation results which can be varied depending on concentration profiles and kinetics of the process. The simulated results were supported by experimental results obtained by a comprehensive heart-cut multidimensional GC (H/C MDGC) approach which was developed to clearly investigate isomerisation of E/Z oxime molecules in both 1D and 2D separations under different isothermal conditions. The carrier gas flow and oven temperature were selected according to initial results for 1D interconversion on a poly(ethyleneglycol) stationary phase, which was further used in both 1D and 2D separations to result in broad zones of oxime interconversion in both dimensions. The method involved repetitive injections of oxime sample, then sampling contiguous fractions of sample into a long 2D column which is intended to promote considerable interconversion. Comprehensiveness arises from the fact that the whole sample is sampled from the 1D to the 2D column, with the long 2D column replacing the short 2D column used in classical comprehensive two-dimensional gas chromatography, where the latter will not promote sufficient interconversion. Data processing and presentation permits a 'rectangular' distribution corresponding to the separated compounds, characteristic of this experiment.

Matched MeSH terms: Chromatography, Gas/methods*
An efficient and biodegradable alginate-gelatin hydrogel beads as bait against Aedes aegypti and Aedes albopictus

Ayub NM, Kassim NFA, Sabar S, Webb CE, Xiang KZ, Hashim NA

Int J Biol Macromol, 2023 Jan 01;224:1460-1470.
PMID: 36328267 DOI: 10.1016/j.ijbiomac.2022.10.233

The effective control of Aedes mosquitoes using traditional control agents is increasingly challenging due to the presence of insecticide resistance in many populations of key mosquito vectors. An alternative strategy to insecticides is the use of toxic sugar baits, however it is limited due to short-term efficacy. Alginate-Gelatin hydrogel beads (AGHBs) may be an effective alternative by providing longer periods of mosquito attraction and control, especially of key vectors of dengue viruses such as Aedes aegypti and Aedes albopictus. Sodium alginate (ALG) and gelatin (GLN) are natural polymers, which can be a potential candidate to develop the AGHBs baits due to their biodegradability and environmental safety. Here we provide an assessment of the preparation of AGHBs optimized by varying the concentrations of ALG, GLN, and its cross-linking time (TIME). Fourier transform infrared spectroscopy (FTIR) analysis results in the determination of liquid bait loaded in the AGHBs. The evaluation of AGHBs' effectiveness as the potential baiting tool based on the mortality rate of mosquitoes after the bait consumption. The 100 % percent mortality of Aedes mosquitoes was obtained within 72 h of bait consumption. The field evaluation also justifies the applicability of AGHBs for outdoor applications. We conclude that the AGHBs are applicable as a baiting tool in carrying liquid bait in achieving mosquito mortality.

Matched MeSH terms: Mosquito Control/methods
Loop-mediated isothermal amplification (LAMP) test in the detection of uncomplicated malaria in pregnancy: a meta-analysis of diagnostic accuracy

Yon JLT, Htet NH, Naing C, Tung WS, Aung HH, Mak JW

Malar J, 2022 Dec 22;21(1):391.
PMID: 36550507 DOI: 10.1186/s12936-022-04419-9

BACKGROUND: Due to relatively low malaria parasitaemia in pregnancy, an appropriate field test that can adequately detect infections in pregnant women presenting with illness or for malaria screening during antenatal care is crucially important. The objective was to evaluate the diagnostic accuracy of loop-mediated isothermal amplification (LAMP) for the detection of uncomplicated malaria in pregnancy.
METHODS: This was a meta-analysis of diagnostic accuracy. Relevant studies that assessed the diagnostic performance of LAMP for the detection of malaria in pregnancy were searched in health-related electronic databases including PubMed, Ovid, and Google Scholar. The methodological quality of the studies included was evaluated using the QUADAS-2 tool.
RESULTS: Of the 372 studies identified, eight studies involving 2999 pregnant women in five endemic countries that assessed the accuracy of LAMP were identified. With three types of PCR as reference tests, the pooled sensitivity of LAMP was 91% (95%CI 67-98%) and pooled specificity was 99% (95%CI 83-100%, 4 studies), and the negative likelihood ratio was 9% (2-40%). Caution is needed in the interpretation as there was substantial between-study heterogeneity (I2: 80%), and a low probability that a person without infection is tested negative. With microscopy as a reference, the pooled sensitivity of LAMP was 95% (95%CI 26-100%) and pooled specificity was 100% (95%CI 94-100%, 4 studies). There was a wide range of sensitivity and substantial between-study heterogeneity (I2: 83.5-98.4%). To investigate the source of heterogeneity, a meta-regression analysis was performed with covariates. Of these potential confounding factors, reference test (p: 0.03) and study design (p:0.03) had affected the diagnostic accuracy of LAMP in malaria in pregnancy. Overall, there was a low certainty of the evidence in accuracy estimates.
CONCLUSION: The findings suggest that LAMP is more sensitive than traditional tests used at facilities, but the utility of detecting and treating these low-density infections is not well understood. Due to the limited number of studies with bias in their methodological quality, variation in the study design, and different types of reference tests further research is likely to change the estimate. Well-conceived large prospective studies with blinding of the index test results are recommenced.

Matched MeSH terms: Nucleic Acid Amplification Techniques/methods
Fulltext Health risk assessment and source apportionment of potentially toxic metal(loid)s in windowsill dust of a rapidly growing urban settlement, Iran

Madadi R, Mohamadi S, Rastegari M, Karbassi A, Rakib MRJ, Khandaker MU, et al.

Sci Rep, 2022 Nov 17;12(1):19736.
PMID: 36396803 DOI: 10.1038/s41598-022-21242-z

Rapid industrialization and urbanization have resulted in environmental pollution and unsustainable development of cities. The concentration of 12 potentially toxic metal(loid)s in windowsill dust samples (n = 50) were investigated from different functional areas of Qom city with the highest level of urbanization in Iran. Spatial analyses (ArcGIS 10.3) and multivariate statistics including Principal Component Analysis and Spearman correlation (using STATISTICA-V.12) were adopted to scrutinize the possible sources of pollution. The windowsill dust was very highly enriched with Sb (50 mg/kg) and Pb (1686 mg/kg). Modified degree of contamination (mCd) and the pollution load indices (PLIzone) indicate that windowsill dust in all functional areas was polluted in the order of industrial > commercial > residential > green space. Arsenic, Cd, Mo, Pb, Sb, Cu, and Zn were sourced from a mixture of traffic and industrial activities, while Mn in the dust mainly stemmed from mining activities. Non-carcinogenic health risk (HI) showed chronic exposure of Pb for children in the industrial zone (HI = 1.73). The estimations suggest the possible carcinogenic risk of As, Pb, and Cr in the dust. The findings of this study reveal poor environmental management of the city. Emergency plans should be developed to minimize the health risks of dust to residents.

Matched MeSH terms: Environmental Monitoring/methods
Influence of sanitary conditions on the field performance of chlorpyrifos-based baits against American cockroaches, Periplaneta americana (L.) (Dictyoptera: Blattidae)

Lee CY, Lee LC

J Vector Ecol, 2000 Dec;25(2):218-21.
PMID: 11217220

The role of sanitation in performance of insecticidal bait stations containing 0.5% chlorpyrifos against the American cockroach, Periplaneta americana (L.), was investigated in residential premises. Test sites were chosen from three locations in Penang Island, Malaysia, and clustered according to their sanitary conditions. Results indicated that at 1-week post-treatment, houses with good sanitary conditions showed a significantly faster reduction (P > 0.05) in the number of cockroaches trapped (> 95%) than those with moderate and poor conditions. At 6 weeks post-treatment, all houses treated with insecticidal baits showed no significant difference in terms of reduction rate of cockroach numbers (P > 0.05), irrespective of sanitary condition. However, the bait performance in houses with poor sanitary conditions could not be sustained up to 12-week post-treatment.

Matched MeSH terms: Insect Control/methods*
Susceptibility of Musca domestica L. (Diptera: Muscidae) from various breeding sites to commonly used insecticides

Nazni WA, Ursula MP, Lee HL, Sa'diyah I

J Vector Ecol, 1999 Jun;24(1):54-60.
PMID: 10436878

Field strains of house flies, Musca domestica L., from three different breeding sites-garbage dump (IMR), poultry farm (Kundang, Selangor), and agricultural farm (Kampung Batu, Kuala Lumpur), were evaluated against five insecticides. Resistance status of adult female flies was determined using the modified WHO bioassay methods. The WHO susceptibility strain was used as a reference strain for comparison. Flies from the garbage dump and poultry farm were more resistant to the insecticides than the strain from the agricultural farm. Results obtained from bioassay tests were confirmed by in-vitro microenzyme assays of non-specific esterases and glutathione-S-transferases. Significant differences between the esterase levels of WHO and field strains were observed. Levels of glutathion-S-transferases were approximately the same, which may indicate that other enzymes are involved in house fly resistance.

Matched MeSH terms: Insect Control/methods*
Fulltext Generalizability assessment of COVID-19 3D CT data for deep learning-based disease detection

Fallahpoor M, Chakraborty S, Heshejin MT, Chegeni H, Horry MJ, Pradhan B

Comput Biol Med, 2022 Jun;145:105464.
PMID: 35390746 DOI: 10.1016/j.compbiomed.2022.105464

BACKGROUND: Artificial intelligence technologies in classification/detection of COVID-19 positive cases suffer from generalizability. Moreover, accessing and preparing another large dataset is not always feasible and time-consuming. Several studies have combined smaller COVID-19 CT datasets into "supersets" to maximize the number of training samples. This study aims to assess generalizability by splitting datasets into different portions based on 3D CT images using deep learning.
METHOD: Two large datasets, including 1110 3D CT images, were split into five segments of 20% each. Each dataset's first 20% segment was separated as a holdout test set. 3D-CNN training was performed with the remaining 80% from each dataset. Two small external datasets were also used to independently evaluate the trained models.
RESULTS: The total combination of 80% of each dataset has an accuracy of 91% on Iranmehr and 83% on Moscow holdout test datasets. Results indicated that 80% of the primary datasets are adequate for fully training a model. The additional fine-tuning using 40% of a secondary dataset helps the model generalize to a third, unseen dataset. The highest accuracy achieved through transfer learning was 85% on LDCT dataset and 83% on Iranmehr holdout test sets when retrained on 80% of Iranmehr dataset.
CONCLUSION: While the total combination of both datasets produced the best results, different combinations and transfer learning still produced generalizable results. Adopting the proposed methodology may help to obtain satisfactory results in the case of limited external datasets.

Matched MeSH terms: Tomography, X-Ray Computed/methods
Comparative analysis of an anthraquinone and chalcone derivatives-based virtual combinatorial library. A cheminformatics "proof-of-concept" study

Moshawih S, Hadikhani P, Fatima A, Goh HP, Kifli N, Kotra V, et al.

J Mol Graph Model, 2022 Dec;117:108307.
PMID: 36096064 DOI: 10.1016/j.jmgm.2022.108307

A Laplacian scoring algorithm for gene selection and the Gini coefficient to identify the genes whose expression varied least across a large set of samples were the state-of-the-art methods used here. These methods have not been trialed for their feasibility in cheminformatics. This was a maiden attempt to investigate a complete comparative analysis of an anthraquinone and chalcone derivatives-based virtual combinatorial library. This computational "proof-of-concept" study illustrated the combinatorial approach used to explain how the structure of the selected natural products (NPs) undergoes molecular diversity analysis. A virtual combinatorial library (1.6 M) based on 20 anthraquinones and 24 chalcones was enumerated. The resulting compounds were optimized to the near drug-likeness properties, and the physicochemical descriptors were calculated for all datasets including FDA, Non-FDA, and NPs from ZINC 15. UMAP and PCA were applied to compare and represent the chemical space coverage of each dataset. Subsequently, the Laplacian score and Gini coefficient were applied to delineate feature selection and selectivity among properties, respectively. Finally, we demonstrated the diversity between the datasets by employing Murcko's and the central scaffolds systems, calculating three fingerprint descriptors and analyzing their diversity by PCA and SOM. The optimized enumeration resulted in 1,610,268 compounds with NP-Likeness, and synthetic feasibility mean scores close to FDA, Non-FDA, and NPs datasets. The overlap between the chemical space of the 1.6 M database was more prominent than with the NPs dataset. A Laplacian score prioritized NP-likeness and hydrogen bond acceptor properties (1.0 and 0.923), respectively, while the Gini coefficient showed that all properties have selective effects on datasets (0.81-0.93). Scaffold and fingerprint diversity indicated that the descending order for the tested datasets was FDA, Non-FDA, NPs and 1.6 M. Virtual combinatorial libraries based on NPs can be considered as a source of the combinatorial compound with NP-likeness properties. Furthermore, measuring molecular diversity is supposed to be performed by different methods to allow for comparison and better judgment.

Matched MeSH terms: Combinatorial Chemistry Techniques/methods
Detection and discrimination of sedative-hypnotics in spiked beverage dry residues using attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy combined with chemometrics

Teoh WK, Mohamed Sadiq NS, Saisahas K, Phonchai A, Kunalan V, Md Muslim NZ, et al.

J Forensic Sci, 2023 Jan;68(1):75-85.
PMID: 36273275 DOI: 10.1111/1556-4029.15156

Drugs-facilitated crimes (DFCs) involve the incapacitation of victims under the influence of drugs. Conventionally, a drug administration act is often determined through the examination of biological samples; however, dry residues from any surface, such as drinking glass if related to a DFC could be a potential source of evidence. This study was aimed to establish an attenuated total reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy coupled with chemometrics for the determination of spiked sedative-hypnotics from dry residues of a drug-spiked beverage. In this study, four sedative-hypnotics, namely diazepam, ketamine, nimetazepam, and xylazine were examined using ATR-FTIR spectroscopy. Subsequently, the ATR-FTIR profiles were compared and decomposed by principal component analysis (PCA) followed by linear discriminant analysis (LDA) for their detection and discrimination. Visual comparison of ATR-FTIR profiles revealed distinct spectra among the tested drugs. An initial unsupervised exploratory PCA model indicated the separation of four main sedative-hypnotics clusters, and the proposed PCA score-LDA model had allowed for a 100% accurate classification. Discrimination of sedative-hypnotics from a dry beverage previously spiked with these drugs was also possible upon an additional extraction procedure. In conclusion, ATR-FTIR coupled with PCA score-LDA model was useful in detecting and discriminating sedative-hypnotics, including those that had been previously spiked into a beverage.

Matched MeSH terms: Spectroscopy, Fourier Transform Infrared/methods
Estimation of a cut-off value for immature platelet fraction (IPF) in predicting platelet recovery in dengue patients with thrombocytopenia

Ahmad J, Md Noor S, Mustapha SZ, Idris F

Malays J Pathol, 2022 Dec;44(3):499-508.
PMID: 36591717

INTRODUCTION: Thrombocytopenia is a common complication in dengue that sometimes necessitates platelet transfusion. Immature platelet fraction (IPF) measures immature platelets that indirectly reflect thrombopoiesis and is helpful in predicting platelet recovery.
OBJECTIVES: This study aimed to evaluate the role of IPF% and identify its cut-off value in predicting platelet recovery in dengue patients with thrombocytopenia.
MATERIALS AND METHODS: Serial platelet count and IPF results were obtained from fifty-four confirmed dengue patients with platelet count <50x109 /L. Median peak IPF% and number of patients with platelet recovery were determined. Receiver operating characteristic (ROC) curve is generated to identify the IPF% cut-off value to predict platelet recovery.
RESULTS: Median peak IPF% among dengue patients was 12.15% with 83.3% of them achieving platelet recovery after reaching the peak IPF%. There was a significant difference between median IPF% on day one of admission with peak IPF% among dengue patients. ROC curve analysis showed IFP% of 10.55% can be used to predict platelet recovery with a sensitivity of 69% and a specificity of 67%.
CONCLUSION: IPF% is a reliable and useful parameter in predicting platelet recovery in dengue patients. This would assist the clinician in managing dengue patients especially those with severe thrombocytopenia without giving unnecessary platelet transfusion.

Matched MeSH terms: Platelet Count/methods
Fulltext A sensitive and rapid determination of zinc ion (Zn2+) using electrochemical sensor based on f-MWCNTs/CS/PB/AuE in drinking water

Ringgit G, Siddiquee S, Saallah S, Mohamad Lal MT

Sci Rep, 2022 Nov 03;12(1):18582.
PMID: 36329094 DOI: 10.1038/s41598-022-21926-6

An electrochemical method for detecting the presence of zinc (Zn2+) ions in drinking water was developed using functionalized multi-walled carbon nanotubes (f-MWCNTs) and chitosan (CS). Numerous cylinder-shaped graphene molecules make up f-MWCNTs, which have a high mechanical and electrical conductivity. CS benefits from nanomaterials include biocompatibility, biodegradability, and low toxicity, which are excellent in capacity absorption of metal ions. Dangerous levels of metal ions such as zinc are currently present in drinking water as a result of human and natural activity. Zinc toxicity is associated with a variety of disorders, including Alzheimer's, Parkinson's, diabetes, and cancer. This study incorporated f-MWCNTs and CS with Prussian blue (PB) immobilised on a gold electrode (AuE). Several parameters, including as buffers, pH, scan rate, redox indicator, accumulation time, and volume, were optimised using the cyclic voltammetry (CV) method. According to the CV method, the optimal parameters were phosphate buffered saline (0.1 M, pH 2), 5 mM Prussian blue, 200 mVs-1 scan rate, and 5 s accumulation time. Under ideal circumstances, the differential pulse voltammetry (DPV) method was used to determine the Zn2+ ions concentration range of 0.2-7.0 ppm. The limit of detection (LOD) was 2.60 × 10-7 mol L-1 with a correlation coefficient of R2 = 0.9777. The recovery rate of the developed sensor (f-MWCNTs/CS/PB/AuE) ranged from 95.78 to 98.96%. The developed sensor showed a variety of advantages for detecting Zn2+ in drinking water, including a quick setup process, quick detection, high sensitivity, and mobility. This study developed the essential sensor for monitoring Zn2+ levels in drinking water in the future.

Matched MeSH terms: Electrochemical Techniques/methods
Fulltext Implementation of a colorectal cancer screening intervention in Malaysia (CRC-SIM) in the context of a pandemic: study protocol

Schliemann D, Ramanathan K, Ibrahim Tamin NSB, O'Neill C, Cardwell CR, Ismail R, et al.

BMJ Open, 2022 Sep 01;12(9):e058420.
PMID: 36581978 DOI: 10.1136/bmjopen-2021-058420

INTRODUCTION: Colorectal cancer (CRC) is the second most common cancer in Malaysia and cases are often detected late. Improving screening uptake is key in down-staging cancer and improving patient outcomes. The aim of this study is to develop, implement and evaluate an intervention to improve CRC screening uptake in Malaysia in the context of the COVID-19 pandemic. The evaluation will include ascertaining the budgetary impact of implementing and delivering the intervention.
METHODS AND ANALYSIS: The implementation research logic model guided the development of the study and implementation outcome measures were informed by the 'Reach, Effectiveness, Adoption, Implementation and Maintenance' (RE-AIM) framework. This CRC screening intervention for Malaysia uses home-testing and digital, small media, communication to improve CRC screening uptake. A sample of 780 people aged 50-75 years living in Segamat district, Malaysia, will be selected randomly from the South East Asia Community Observatory (SEACO) database. Participants will receive a screening pack as well as a WhatsApp video of a local doctor to undertake a stool test safely and to send a photo of the test result to a confidential mobile number. SEACO staff will inform participants of their result. Quantitative data about follow-up clinic attendance, subsequent hospital tests and outcomes will be collected. Logistic regression will be used to investigate variables that influence screening completion and we will conduct a budget impact-analysis of the intervention and its implementation. Qualitative data about intervention implementation from the perspective of participants and stakeholders will be analysed thematically.
ETHICS AND DISSEMINATION: Ethics approval has been granted by Monash University Human Research Ethics Committee (MUHREC ID: 29107) and the Medical Review and Ethics Committee (Reference: 21-02045-O7G(2)). Results will be disseminated through publications, conferences and community engagement activities.
TRIAL REGISTRATION NUMBER: National Medical Research Register Malaysia: 21-02045-O7G(2).

Matched MeSH terms: Early Detection of Cancer/methods
Microalgae identification: Future of image processing and digital algorithm

Chong JWR, Khoo KS, Chew KW, Vo DN, Balakrishnan D, Banat F, et al.

Bioresour Technol, 2023 Feb;369:128418.
PMID: 36470491 DOI: 10.1016/j.biortech.2022.128418

The identification of microalgae species is an important tool in scientific research and commercial application to prevent harmful algae blooms (HABs) and recognizing potential microalgae strains for the bioaccumulation of valuable bioactive ingredients. The aim of this study is to incorporate rapid, high-accuracy, reliable, low-cost, simple, and state-of-the-art identification methods. Thus, increasing the possibility for the development of potential recognition applications, that could identify toxic-producing and valuable microalgae strains. Recently, deep learning (DL) has brought the study of microalgae species identification to a much higher depth of efficiency and accuracy. In doing so, this review paper emphasizes the significance of microalgae identification, and various forms of machine learning algorithms for image classification, followed by image pre-processing techniques, feature extraction, and selection for further classification accuracy. Future prospects over the challenges and improvements of potential DL classification model development, application in microalgae recognition, and image capturing technologies are discussed accordingly.

Matched MeSH terms: Image Processing, Computer-Assisted/methods
Fulltext A worldwide perspective on large carnivore attacks on humans

Bombieri G, Penteriani V, Almasieh K, Ambarlı H, Ashrafzadeh MR, Das CS, et al.

PLoS Biol, 2023 Jan;21(1):e3001946.
PMID: 36719873 DOI: 10.1371/journal.pbio.3001946

Large carnivores have long fascinated human societies and have profound influences on ecosystems. However, their conservation represents one of the greatest challenges of our time, particularly where attacks on humans occur. Where human recreational and/or livelihood activities overlap with large carnivore ranges, conflicts can become particularly serious. Two different scenarios are responsible for such overlap: In some regions of the world, increasing human populations lead to extended encroachment into large carnivore ranges, which are subject to increasing contraction, fragmentation, and degradation. In other regions, human and large carnivore populations are expanding, thus exacerbating conflicts, especially in those areas where these species were extirpated and are now returning. We thus face the problem of learning how to live with species that can pose serious threats to humans. We collected a total of 5,440 large carnivore (Felidae, Canidae, and Ursidae; 12 species) attacks worldwide between 1950 and 2019. The number of reported attacks increased over time, especially in lower-income countries. Most attacks (68%) resulted in human injuries, whereas 32% were fatal. Although attack scenarios varied greatly within and among species, as well as in different areas of the world, factors triggering large carnivore attacks on humans largely depend on the socioeconomic context, with people being at risk mainly during recreational activities in high-income countries and during livelihood activities in low-income countries. The specific combination of local socioeconomic and ecological factors is thus a risky mix triggering large carnivore attacks on humans, whose circumstances and frequencies cannot only be ascribed to the animal species. This also implies that effective measures to reduce large carnivore attacks must also consider the diverse local ecological and social contexts.

Matched MeSH terms: Conservation of Natural Resources/methods
Fulltext Development and Evaluation of Self-Emulsifying Drug-Delivery System-Based Tablets for Simvastatin, a BCS Class II Drug

Bashir MA, Khan A, Shah SI, Ullah M, Khuda F, Abbas M, et al.

Drug Des Devel Ther, 2023;17:261-272.
PMID: 36726738 DOI: 10.2147/DDDT.S377686

BACKGROUND: Self-emulsifying drug-delivery systems (SEDDSs) are designed to improve the oral bioavailability of poorly water-soluble drugs. This study aimed at formulating and characterization of SEDDS-based tablets for simvastatin using castor and olive oils as solvents and Tween 60 as surfactant.
METHODS: The liquids were adsorbed on microcrystalline cellulose, and all developed formulations were compressed using 10.5 mm shallow concave round punches.
RESULTS: The resulting tablets were evaluated for different quality-control parameters at pre- and postcompression levels. Simvastatin showed better solubility in a mixture of oils and Tween 60 (10:1). All the developed formulations showed lower self-emulsification time (˂200 seconds) and higher cloud point (˃60°C). They were free of physical defects and had drug content within the acceptable range (98.5%-101%). The crushing strength of all formulations was in the range of 58-96 N, and the results of the friability test were within the range of USP (≤1). Disintegration time was within the official limits (NMT 15 min), and complete drug release was achieved within 30 min.
CONCLUSION: Using commonly available excipients and machinery, SEDDS-based tablets with better dissolution profile and bioavailability can be prepared by direct compression. These S-SEDDSs could be a better alternative to conventional tablets of simvastatin.

Matched MeSH terms: Drug Delivery Systems/methods
Mapping Chini Lake (Pahang, Malaysia) using Sentinel-2 images to determine the effect of acid mine drainage in the pre- to post-COVID-19 restriction period

Rendana M, Idris WMR, Rahim SA

Environ Monit Assess, 2022 Dec 17;195(1):205.
PMID: 36527450 DOI: 10.1007/s10661-022-10833-y

Mining activities in the Chini Lake catchment area have been extensive for several years, contributing to acid mine drainage (AMD) events with high concentrations of iron (Fe) and other heavy metals impacting the surface water. However, during the restriction period due to the COVID-19 outbreak, anthropogenic activities have been suspended, which clearly shows a good opportunity for a better environment. Therefore, we aimed to analyze the variation of AMD-associated water pollution in three main zones of the Chini Lake catchment area using Sentinel-2 data for the periods pre-movement control order (MCO), during MCO, and post-MCO from 2019 to 2021. These three zones were chosen due to their proximity to mining areas: zone 1 in the northeastern part, zone 2 in the southeastern part, and zone 3 in the southern part of the Chini Lake area. The acid mine water index (AMWI) was a specific index used to estimate acid mine water. The AMWI values from Sentinel-2 images exhibited that the mean AMWI values in all zones during the MCO period decreased by 14% compared with the pre-MCO period. The spatiotemporal analysis found that the highest polluted zones were recorded in zone 1, followed by zone 3 and zone 2. As compared with during the MCO period, the maximum percentage of increment during post-MCO in all zones was up to 25%. The loosened restriction policy has resulted in more AMD flowing into surface water and increased pollution in Chini Lake. As a whole, our outputs revealed that Sentinel-2 data had a major potential for assessing the AMD-associated pollution of water.

Matched MeSH terms: Environmental Monitoring/methods
Fulltext Volumetric evaluation of the sphenoid sinus among different races in the Southeast Asian (SEA) population: a computerized tomography study

Tuang GJ, Zahedi FD, Husain S, Hamizan AKW, Kew TY, Thanabalan J

Int J Med Sci, 2023;20(2):211-218.
PMID: 36794158 DOI: 10.7150/ijms.68095

Introduction: The fundament of forensic science lies in identifying a body. The morphological complexity of the paranasal sinus (PNS), which varies greatly amongst individual, possess a discriminatory value that potentially contributes to the radiological identification. The sphenoid bone represents the keystone of the skull and forms part of the cranial vault. It is intimately associated with vital neurovascular structures. The sphenoid sinus, located within the body of the sphenoid bone, has variable morphology. The sphenoid septum's inconsistent position and the degree, as well as the direction disparities of sinus pneumatization, have indeed accorded it a unique structure in providing invaluable information in forensic personnel identification. Additionally, the sphenoid sinus is situated deep within the sphenoid bone. Therefore, it is well protected from traumatic degradation from external causes and can be potentially utilized in forensic studies. The authors aim to study the possibility of variation among the race, and gender in the Southeast Asian (SEA) population, using volumetric measurements of the sphenoid sinus. Materials and methods: This is a retrospective cross-sectional analysis of computerized tomographic (CT) imaging of the PNS of 304 patients (167 males, 137 females) in a single centre. The volume of the sphenoid sinus was reconstructed and measured using commercial real-time segmentation software. Result: The total volume of sphenoid sinus of male gender had shown to be larger, 12.22 (4.93 - 21.09) cm3 compared to the counterpart of 10.19 (3.75 - 18.72) cm3 (p = .0090). The Chinese possessed a larger total sphenoid sinus volume, 12.96 (4.62 - 22.21) cm3) than the Malays, 10.68 (4.13 - 19.25) cm3 (p = .0057). No correlation was identified between the age and volume of the sinus (cc= -.026, p = .6559). Conclusion: The sphenoid sinus volume in males was found to be larger than those of females. It was also shown that race influences sinus volume. Volumetric analysis of the sphenoid sinus can potentially be utilized in gender and race determination. The current study provided normative data on the sphenoid sinus volume in the SEA region, which can be helpful for future studies.

Matched MeSH terms: Tomography, X-Ray Computed/methods
Fulltext Recent advances in immunoassay-based mycotoxin analysis and toxicogenomic technologies

Liew WP, Sabran MR

J Food Drug Anal, 2022 Nov 23;30(4):549-561.
PMID: 36753365 DOI: 10.38212/2224-6614.3430

The co-occurrence and accumulation of mycotoxin in food and feed constitutes a major issue to food safety, food security, and public health. Accurate and sensitive mycotoxins analysis can avoid toxin contamination as well as reduce food wastage caused by false positive results. This mini review focuses on the recent advance in detection methods for multiple mycotoxins, which mainly depends on immunoassay technologies. Advance immunoassay technologies integrated in mycotoxin analysis enable simultaneous detection of multiple mycotoxins and enhance the outcomes' quality. It highlights toxicogenomic as novel approach for hazard assessment by utilizing computational methods to map molecular events and biological processes. Indeed, toxicogenomic is a powerful tool to understand health effects from mycotoxin exposure as it offers insight on the mechanisms by which mycotoxins exposures cause diseases.

Matched MeSH terms: Immunoassay/methods
Fulltext A highly sensitive LC-MS/MS method for quantitative determination of 7 vitamin D metabolites in mouse brain tissue

Stephenson AJ, Hunter B, Shaw PN, Kassim NSA, Trengove R, Takechi R, et al.

Anal Bioanal Chem, 2023 Mar;415(7):1357-1369.
PMID: 36705732 DOI: 10.1007/s00216-023-04527-8

Despite its critical role in neurodevelopment and brain function, vitamin D (vit-D) homeostasis, metabolism, and kinetics within the central nervous system remain largely undetermined. Thus, it is of critical importance to establish an accurate, highly sensitive, and reproducible method to quantitate vit-D in brain tissue. Here, we present a novel liquid chromatography tandem mass spectrometry (LC-MS/MS) method and for the first time, demonstrate detection of seven major vit-D metabolites in brain tissues of C57BL/6J wild-type mice, namely 1,25(OH)2D3, 3-epi-1,25(OH)2D3, 1,25(OH)2D2, 25(OH)D3, 25(OH)D2, 24,25(OH)2D3, and 24,25(OH)2D2. Chromatographic separation was achieved on a pentaflurophenyl column with 3 mM ammonium formate water/methanol [A] and 3 mM ammonium formate methanol/isopropanol [B] mobile phase components. Detection was by positive ion electrospray tandem mass spectrometry with the EVOQ elite triple quadrupole mass spectrometer with an Advance ultra-high-performance liquid chromatograph and online extraction system. Calibration standards of each metabolite prepared in brain matrices were used to validate the detection range, precision, accuracy, and recovery. Isotopically labelled analogues, 1,25(OH)2D3-d3, 25(OH)D3-c5, and 24,25(OH)2D3-d6, served as the internal standards for the closest molecular-related metabolite in all measurements. Standards between 1 fg/mL and 10 ng/mL were injected with a resulting linear range between 0.001 and 1 ng, with an LLOD and LLOQ of 1 pg/mL and 12.5 pg/mL, respectively. The intra-/inter-day precision and accuracy for measuring brain vit-D metabolites ranged between 0.12-11.53% and 0.28-9.11%, respectively. Recovery in acetonitrile ranged between 99.09 and 106.92% for all metabolites. Collectively, the sensitivity and efficiency of our method supersedes previously reported protocols used to measure vit-D and to our knowledge, the first protocol to reveal the abundance of 25(OH)D2, 1,25(OH)D2, and 24,25(OH)2D2, in brain tissue of any species. This technique may be important in supporting the future advancement of pre-clinical research into the function of vit-D in neurophysiological and neuropsychiatric disorders, and neurodegeneration.

Matched MeSH terms: Chromatography, Liquid/methods
Occupational ergonomics and related musculoskeletal disorders among dentists: A systematic review

Soo SY, Ang WS, Chong CH, Tew IM, Yahya NA

Work, 2023;74(2):469-476.
PMID: 36278379 DOI: 10.3233/WOR-211094

BACKGROUND: There is an increasing concern about musculoskeletal disorders (MSD), resulting from occupational health hazards among dentists. Dentists who are susceptible to occupational health hazards could develop cumulative trauma disorders, lead to absenteeism from work, loss of productivity and performance or even long-term disability.
OBJECTIVE: This study aims to determine the prevalence of musculoskeletal disorders among dentists, explore the risk factors and identify the ergonomic preventive measures for dental professionals.
METHODS: Articles published between 2008-2020 were searched in scientific databases (MEDLINE, PubMed, Scopus and Cochrane Library). The Critical Appraisal Skills Programme Systematic Review Checklist was used to assess the quality of the studies.
RESULTS: Eighteen studies were found to be suitable in the final review. Relevant data was extracted and summarized from the included studies. The annual prevalence of musculoskeletal disorders in any body site ranged between 68% and 100%. The most predominant regions for musculoskeletal disorders among dental professionals were identified to be the lower back (29% to 94.6%), shoulder (25% to 92.7%), and neck (26% to 92%). The most frequently reported risk factors of MSDs were the individual characteristic female gender (57.1%), followed by awkward working postures (50%), long working experience (50%) and being dental specialists (42.9%). Several preventive measures were identified as the most effective ways in preventing MSDs, the use of magnification (40%) and regular physical activity (40%).
CONCLUSIONS: This review reported a high prevalence of musculoskeletal disorders (MSD) among dentists. It critically updates and adds the latest evidence on occupational ergonomics among dentists.

Matched MeSH terms: Human Engineering/methods

Filters

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

External Links