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On the prediction of methane fluxes from pristine tropical peatland in Sarawak: application of a denitrification-decomposition (DNDC) model

Sa'adi Z, Yaseen ZM, Muhammad MKI, Iqbal Z

Environ Sci Pollut Res Int, 2022 Jan 07.
PMID: 34993788 DOI: 10.1007/s11356-021-17917-1

Tropical peatlands have high potential function as a major source of atmospheric methane (CH4) and can contribute to global warming due to their large soil carbon stock, high groundwater level (GWL), high humidity and high temperature. In this study, a process-based denitrification-decomposition (DNDC) model was used to simulate CH4 fluxes in a pristine tropical peatland in Sarawak. To test the accuracy of the model, eddy covariance tower datasets were compared. The model was validated for the year 2014, which showed the good performance of the model for simulating CH4 emissions. The monthly predictive ability of the model was better than the daily predictive ability, with a determination coefficient (R2) of 0.67, model error (ME) of 2.47, root mean square error (RMSE) of 3.33, mean absolute error (MAE) of 2.92 and mean square error (MSE) of 11.08. The simulated years of 2015 and 2016 showed the good performance of the DNDC model, although under- and overestimations were found during the drier and rainy months. Similarly, the monthly simulations for the year were better than the daily simulations for the year, showing good correlations at R2 at 0.84 (2015) and 0.87 (2016). Better statistical performance in terms of monthly ME, RMSE, MAE and MSE at - 0.11, 3.38, 3.05 and 11.45 for 2015 and - 1.14, 5.28, 4.93 and 27.83 for 2016, respectively, was also observed. Although the statistical performance of the model simulation for daily average CH4 fluxes was lower than that of the monthly average, we found that the results for total fluxes agreed well between the observed and the simulated values (E = 6.79% and difference = 3.3%). Principal component analysis (PCA) showed that CH4, GWL and rainfall were correlated with each other and explained 41.7% of the total variation. GWL was found to be relatively important in determining the CH4 fluxes in the naturally inundated pristine tropical peatland. These results suggest that GWL is an essential input variable for the DNDC model for predicting CH4 fluxes from the pristine tropical peatland in Sarawak on a monthly basis.
Different pontic design for porcelain fused to metal fixed dental prosthesis: Contemporary guidelines and practice by general dental practitioners

Raza Kazmi SM, Iqbal Z, Muneer MU, Riaz S, Zafar MS

Eur J Dent, 2018 8 28;12(3):375-379.
PMID: 30147402 DOI: 10.4103/ejd.ejd_232_18

Objective: The current study aimed to assess the knowledge and practice of pontic design selection by the general dental practitioners (GDPs) in the light of contemporary guidelines.
Materials and Methods: This cross-sectional study was conducted among the GDPs of Karachi. A questionnaire was designed to collect data from 100 GDPs. The questionnaire included general/demographic information (practitioner's education, experience, and place of practice) and an average number of fixed prosthesis constructed by the GDP. The questionnaire was further categorized to evaluate the knowledge/practice of pontic design selection and latest recommendations.
Results: For the maxillary anterior segment, the ridge lap pontic was the most common (32%) followed by the modified ridge lap (28%). In the maxillary posterior segment, the ridge lap pontic was the most common (37%) followed by sanitary design (34%). For the mandibular anterior segment, the modified ridge lap (50%) was the most common followed by ridge lap pontic (17%). In case of the mandibular posterior segment, the sanitary design (34%) was the most common followed by ridge lap pontic (30%).
Conclusions: The pontic design selection for the fixed prosthesis is a neglected domain. The contemporary guidelines are not followed with full spirit by the GDPs leading to wide variations in the pontic design selection.
Antidiabetic and antidyslipidemic potential of Echinops echinatus in rat models of type I and type II diabetes

Chaudhry SRY, Akram A, Aslam N, Wajid M, Iqbal Z, Nazir I, et al.

Pak J Pharm Sci, 2019 Mar;32(2):505-514.
PMID: 31081759

Echinops echinatus is traditionally an important plant that finds its extensive use as a diuretic, anti-inflammatory, anti-pyretic, nerve tonic, abortifacient, aphrodisiac, antiasthmatic, and antidiabetic agent. The current study investigates protection against the hyperglycemia and dyslipidemia in alloxan-induced (type I diabetes) and fructose-fed insulin resistance (type II diabetes) models of diabetes treated with aqueous methanolic root extract of E. echinatus (Ee.Cr). Albino rats were treated orally with Ee.Cr at doses 100, 300 and 500mg/kg. The fasting blood glucose was measured by glucometer, while standard kits were used to determine the levels of serum total cholesterol, triglycerides and HDL. The administration of Ee.Cr significantly (P<0.001) reduced the FBG concentration in a dose-dependent pattern in alloxan-induced and fructose-fed diabetic rats. The Ee.Cr also corrected the dyslipidemia associated with fructose and alloxan-induced diabetes by significantly (P<0.001) decreasing the concentration of serum total cholesterol, triglycerides, and LDL and by increasing HDL concentration. Ee.Cr also significantly (P<0.001) improved the glucose tolerance in fructose-fed rats. We conclude that Ee.Cr has antidiabetic and antidyslipidemic effects in both insulin-dependent alloxan-induced diabetes and fructose-induced insulin resistance diabetes rat models.
Vasorelaxant activities and the underlying pharmacological mechanisms of Gynura procumbens Merr. leaf extracts on rat thoracic aorta

Iqbal Z, Bello I, Asmawi MZ, Al-Mansoub MA, Ahmad A, Jabeen Q, et al.

Inflammopharmacology, 2019 Apr;27(2):421-431.
PMID: 29185178 DOI: 10.1007/s10787-017-0422-4

Previous studies have investigated the cardiovascular activity of Gynura procumbens Merr. single-solvent extracts. The objective of this study was to evaluate the in vitro vasorelaxant properties and the underlying pharmacological mechanisms of serial extracts and fractions of Gynura procumbens (GP). The leaves of GP were serially extracted with petroleum ether, chloroform, methanol and water using the maceration method. Suspended aortic ring preparations were pre-contracted with phenylephrine (PE 1 µM), followed by cumulative addition of GP extracts (0.25-3 mg/mL). The petroleum ether extract (GPPE) was the most potent among the four extracts. Pre-incubation of endothelium-intact aorta with atropine (1 µM), indomethacin (10 µM), methylene blue (10 µM), propranolol (1 µM) and potassium channel blockers such as TEA (1 µM), glibenclamide (10 µM), 4-aminopyridine (1 µM) and barium chloride (10 mM) had no effect on GPPE-induced vasorelaxation. The vasorelaxant effect of GPPE was partly diminished by pretreatment of aortic rings preparations with L-NAME (10 µM) and even more so in endothelium-denuded aortic rings, indicating a minimal involvement of endothelium-dependent pathway in GPPE-induced vasorelaxation. The calcium-induced vasocontractions were antagonized significantly and concentration-dependently by GPPE in calcium free and high potassium medium. These results illustrate that Ca2+ antagonizing actions of GPPE in rat isolated aorta are comparable to that of verapamil and may be mainly responsible for its vasodilation effect. The antioxidant activity of GPPE supports its vasorelaxant effect by attenuating the production of deleterious free radicals and reactive oxygen species in the vasculature.
Fulltext Biomedical Application, Patent Repository, Clinical Trial and Regulatory Updates on Hydrogel: An Extensive Review

Mohapatra S, Mirza MA, Hilles AR, Zakir F, Gomes AC, Ansari MJ, et al.

Gels, 2021 Nov 12;7(4).
PMID: 34842705 DOI: 10.3390/gels7040207

Hydrogels are known for their leading role in biomaterial systems involving pharmaceuticals that fascinate material scientists to work on the wide variety of biomedical applications. The physical and mechanical properties of hydrogels, along with their biodegradability and biocompatibility characteristics, have made them an attractive and flexible tool with various applications such as imaging, diagnosis and treatment. The water-cherishing nature of hydrogels and their capacity to swell-contingent upon a few ecological signals or the simple presence of water-is alluring for drug conveyance applications. Currently, there are several problems relating to drug delivery, to which hydrogel may provide a possible solution. Hence, it is pertinent to collate updates on hydrogels pertaining to biomedical applications. The primary objective of this review article is to garner information regarding classification, properties, methods of preparations, and of the polymers used with particular emphasis on injectable hydrogels. This review also covers the regulatory and other commerce specific information. Further, it enlists several patents and clinical trials of hydrogels with related indications and offers a consolidated resource for all facets associated with the biomedical hydrogels.
Fulltext Quercetin as a Therapeutic Product: Evaluation of Its Pharmacological Action and Clinical Applications-A Review

Mirza MA, Mahmood S, Hilles AR, Ali A, Khan MZ, Zaidi SAA, et al.

Pharmaceuticals (Basel), 2023 Nov 20;16(11).
PMID: 38004496 DOI: 10.3390/ph16111631

Quercetin is the major polyphenolic flavonoid that belongs to the class called flavanols. It is found in many foods, such as green tea, cranberry, apple, onions, asparagus, radish leaves, buckwheat, blueberry, broccoli, and coriander. It occurs in many different forms, but the most abundant quercetin derivatives are glycosides and ethers, namely, Quercetin 3-O-glycoside, Quercetin 3-sulfate, Quercetin 3-glucuronide, and Quercetin 3'-metylether. Quercetin has antioxidant, anti-inflammatory, cardioprotective, antiviral, and antibacterial effects. It is found to be beneficial against cardiovascular diseases, cancer, diabetes, neuro-degenerative diseases, allergy asthma, peptic ulcers, osteoporosis, arthritis, and eye disorders. In pre-clinical and clinical investigations, its impacts on various signaling pathways and molecular targets have demonstrated favorable benefits for the activities mentioned above, and some global clinical trials have been conducted to validate its therapeutic profile. It is also utilized as a nutraceutical due to its pharmacological properties. Although quercetin has several pharmacological benefits, its clinical use is restricted due to its poor water solubility, substantial first-pass metabolism, and consequent low bioavailability. To circumvent this limited bioavailability, a quercetin-based nanoformulation has been considered in recent times as it manifests increased quercetin uptake by the epithelial system and enhances the delivery of quercetin to the target site. This review mainly focuses on pharmacological action, clinical trials, patents, marketed products, and approaches to improving the bioavailability of quercetin with the use of a nanoformulation.
Application of relative importance metrics for CMIP6 models selection in projecting basin-scale rainfall over Johor River basin, Malaysia

Sa'adi Z, Alias NE, Yusop Z, Iqbal Z, Houmsi MR, Houmsi LN, et al.

Sci Total Environ, 2024 Feb 20;912:169187.
PMID: 38097068 DOI: 10.1016/j.scitotenv.2023.169187

The most recent set of General Circulation Models (GCMs) derived from the Coupled Model Intercomparison Project Phase 6 (CMIP6) was used in this work to analyse the spatiotemporal patterns of future rainfall distribution across the Johor River Basin (JRB) in Malaysia. A group of 23 GCMs were chosen for comparative assessment in simulating basin-scale rainfall based on daily rainfall from the historical period of the Climate Hazards Group InfraRed Precipitation with Station Data (CHIRPS). The methodological novelty of this study lies in the application of relative importance metrics (RIM) to rank and select historical GCM simulations for reproducing rainfall at 109 CHIRPS grid points within the JRB. In order to choose the top GCMs, the rankings given by RIM were aggregated using the compromise programming index (CPI) and Jenks optimised classification (JOC). It was found that ACCESS-ESM1-5 and CMCC-ESM2 were ranked the highest in most of the grid. The final GCM was then bias-corrected using the linear scaling method before being ensemble based on the Bayesian model averaging (BMA) technique. The spatiotemporal assessment of the ensemble model for the different months over the near-future period 2021-2060 and far-future period 2061-2100 was compared with those under Shared Socioeconomic Pathways (SSPs), namely, SSP1-2.6, SSP2-4.5, SSP3-7.0, and SSP5-8.5. Heterogeneous changes in rainfall were projected across the JRB, with both increasing and decreasing trends. In the near-future and far-future scenarios, higher rainfall was projected for December, indicating an elevated risk of flooding during the end of the North East monsoon (NEM). Conversely, August showed a decreasing trend in rainfall, implying an increasing risk of severe drought. The findings of this study provide valuable insights for effective water resource management and climate change adaptation in the region.
Fulltext Enhancing lung cancer detection through hybrid features and machine learning hyperparameters optimization techniques

Li L, Yang J, Por LY, Khan MS, Hamdaoui R, Hussain L, et al.

Heliyon, 2024 Feb 29;10(4):e26192.
PMID: 38404820 DOI: 10.1016/j.heliyon.2024.e26192

Machine learning offers significant potential for lung cancer detection, enabling early diagnosis and potentially improving patient outcomes. Feature extraction remains a crucial challenge in this domain. Combining the most relevant features can further enhance detection accuracy. This study employed a hybrid feature extraction approach, which integrates both Gray-level co-occurrence matrix (GLCM) with Haralick and autoencoder features with an autoencoder. These features were subsequently fed into supervised machine learning methods. Support Vector Machine (SVM) Radial Base Function (RBF) and SVM Gaussian achieved perfect performance measures, while SVM polynomial produced an accuracy of 99.89% when utilizing GLCM with an autoencoder, Haralick, and autoencoder features. SVM Gaussian achieved an accuracy of 99.56%, while SVM RBF achieved an accuracy of 99.35% when utilizing GLCM with Haralick features. These results demonstrate the potential of the proposed approach for developing improved diagnostic and prognostic lung cancer treatment planning and decision-making systems.
Fulltext Viscosine as a Potent and Safe Antipyretic Agent Evaluated by Yeast-Induced Pyrexia Model and Molecular Docking Studies

Muhammad A, Khan B, Iqbal Z, Khan AZ, Khan I, Khan K, et al.

ACS Omega, 2019 Sep 03;4(10):14188-14192.
PMID: 31508540 DOI: 10.1021/acsomega.9b01041

The antipyretic potential of viscosine, a natural product isolated from the medicinal plant Dodonaea viscosa, was investigated using yeast-induced pyrexia rat model, and its structure-activity relationship was investigated through molecular docking analyses with the target enzymes cyclooxygenase-1 (COX-1), cyclooxygenase-2 (COX-2), and microsomal prostaglandin E synthase-1 (mPGES-1). The in vivo antipyretic experiments showed a progressive dose-dependent reduction in body temperatures of the hyperthermic test animals when injected with viscosine. Comparison of docking analyses with target enzymes showed strongest bonding interactions (binding energy -17.34 kcal/mol) of viscosine with the active-site pocket of mPGES-1. These findings suggest that viscosine shows antipyretic properties by reducing the concentration of prostaglandin E2 in brain through its mPGES-1 inhibitory action and make it a potential lead compound for developing effective and safer antipyretic drugs for treating fever and related pathological conditions.
Fulltext Phytochemical analysis and protective effects of Vaccinium macrocarpon (cranberry) in rats (Rattus norvegicus) following ethylene oxide-induced oxidative insult

Rasool M, Malik A, Abdul Basit Ashraf M, Mubbin R, Ayyaz U, Waquar S, et al.

Bioengineered, 2021 12;12(1):4593-4604.
PMID: 34346287 DOI: 10.1080/21655979.2021.1955528

The Vaccinium genus comprises more than 126 genera of perennial flowering plants that are commonly adapted to poor and acidic soils or epiphytic environments. Their molecular and genomic characterization is a result of the recent advent in next-generation sequencing technology. In the current research, extracts were prepared in different media, such as petroleum ether, methanol and ethanol. An extract of Vaccinium macrocarpon (cranberry) was used at a dose of 200-400 mg/kg by weight (B.wt). Levels of oxidative stress markers, i.e., superoxide dismutase (SOD), catalase (CAT), glutathione (GSH), advanced oxidation protein products (AOPPs) and malondialdehyde (MDA), were measured. A histopathological study of six vital organs in rats was also conducted. The results indicated that the antioxidant levels were lower in the group given only ethylene oxide (EtO) but higher in the groups receiving cranberry extract as a treatment. Major improvements were also observed in stress markers such as advanced oxidation protein products (AOPPs) and MDA following cranberry treatment. Histopathological changes induced by EtO were observed in the heart, kidney, liver, lung, stomach and testis and were reversed following cranberry treatment. The major toxic effects of EtO were oxidative stress and organ degeneration, as observed from various stress markers and histopathological changes. Our study showed that this extract contains strong antioxidant properties, which may contribute to the amelioration of the observed toxic effects.
Pattern of first- and second-line drug resistance among pulmonary tuberculosis retreatment cases in Pakistan

Javaid A, Hasan R, Zafar A, Chaudry MA, Qayyum S, Qadeer E, et al.

Int J Tuberc Lung Dis, 2017 03 01;21(3):303-308.
PMID: 28225340 DOI: 10.5588/ijtld.16.0444

BACKGROUND: Drug resistance in general, and multidrug-resistant tuberculosis (MDR-TB) in particular, threatens global tuberculosis (TB) control efforts. Population-based estimates of drug resistance are needed to develop strategies for controlling drug-resistant TB in Pakistan.
OBJECTIVE: To obtain population-based data on Mycobacterium tuberculosis drug resistance in Pakistan.
METHODS: To obtain drug resistance data, we conducted a population-based study of TB cases in all provinces of Pakistan. We performed culture and drug susceptibility testing on M. tuberculosis isolates from patients with a prior history of anti-tuberculosis treatment (retreatment cases) from all over the country.
RESULTS: Of 544 isolates from previously treated cases, 289 (53.1%) were susceptible to all first-line drugs, 255 (46.9%) were resistant to at least one anti-tuberculosis drug and 132 (24.3%) were MDR-TB. Among MDR-TB isolates, 47.0% were ofloxacin (OFX) resistant. Extensively drug-resistant TB was found in two (0.4%) isolates.
CONCLUSION: Prevalence of drug resistance in retreatment isolates was high. The alarmingly high prevalence of OFX resistance among MDR-TB isolates may threaten the success of efforts to control and treat MDR-TB.
Fulltext Avoiding catastrophes: seeking synergies among the public health, environmental protection, and human security sectors

Stoett P, Daszak P, Romanelli C, Machalaba C, Behringer R, Chalk F, et al.

Lancet Glob Health, 2016 10;4(10):e680-1.
PMID: 27633423 DOI: 10.1016/S2214-109X(16)30173-5

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