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Fulltext Patient Perspective on Iron Chelation Therapy: Barriers and Facilitators of Medication Adherence

Chong CC, Redzuan AM, Sathar J, Makmor-Bakry M

J Patient Exp, 2021;8:2374373521996958.
PMID: 34179377 DOI: 10.1177/2374373521996958

Nonadherence to iron chelation therapy (ICT) remains a long-standing and serious issue in thalassemia, especially in resource-constrained developing countries. Barriers and facilitators of adherence to ICT in transfusion-dependent thalassemia (TDT) adult patients in Malaysia are not completely understood. This qualitative study explored factors affecting adherence to ICT among TDT adult patients at a public tertiary hospital in Malaysia. Data were collected through 21 semistructured in-depth interviews conducted among purposively sampled patients using a pretested interview guide. All interviews were audio-recorded and transcribed verbatim. Data were analyzed manually using thematic analysis method and managed using Atlas.Ti software. The most frequently discussed subthemes of barriers to adherence included patient-related factors, medications-related factors, sociocultural-related factors, environmental context and resources, and patient-health care provider relationship factors. The facilitators to adherence included having insights of their illness, prevailing sources of motivation emphasizing on strong self-efficacy, low medication burden, and having enabling environment. This study has identified barriers and facilitators that are unique to Malaysian thalassemic adults related to medication adherence. Options for future multifaceted interventions are suggested.
Holistic process evaluation of non-conventional palm oil mill effluent (POME) treatment technologies: A conceptual and comparative review

Cheng YW, Chong CC, Lam MK, Ayoub M, Cheng CK, Lim JW, et al.

J Hazard Mater, 2021 05 05;409:124964.
PMID: 33418292 DOI: 10.1016/j.jhazmat.2020.124964

Thriving oil palm agroindustry comes at a price of voluminous waste generation, with palm oil mill effluent (POME) as the most cumbersome waste due to its liquid state, high strength, and great discharge volume. In view of incompetent conventional ponding treatment, a voluminous number of publications on non-conventional POME treatments is filed in the Scopus database, mainly working on alternative or polishing POME treatments. In dearth of such comprehensive review, all the non-conventional POME treatments are rigorously reviewed in a conceptual and comparative manner. Herein, non-conventional POME treatments are sorted into the five major routes, viz. biological (bioconversions - aerobic/anaerobic biodegradation), physical (flotation & membrane filtration), chemical (Fenton oxidation), physicochemical (photooxidation, steam reforming, coagulation-flocculation, adsorption, & ultrasonication), and bioelectrochemical (microbial fuel cell) pathways. For aforementioned treatments, the constraints, pros, and cons are qualitatively and quantitatively (with compiled performance data) detailed to indicate their process maturity. Authors recommended (i) bioconversions, adsorption, and steam reforming as primary treatments, (ii) flotation and ultrasonication as pretreatments, (iii) Fenton oxidation, photooxidation, and membrane filtration as polishing treatments, and (iv) microbial fuel cell and coagulation-flocculation as pretreatment or polishing treatment. Life cycle assessments are required to evaluate the environmental, economic, and energy aspects of each process.
Anaerobic digestate as a low-cost nutrient source for sustainable microalgae cultivation: A way forward through waste valorization approach

Chong CC, Cheng YW, Ishak S, Lam MK, Lim JW, Tan IS, et al.

Sci Total Environ, 2022 Jan 10;803:150070.
PMID: 34525689 DOI: 10.1016/j.scitotenv.2021.150070

To suffice the escalating global energy demand, microalgae are deemed as high potential surrogate feedstocks for liquid fuels. The major encumbrance for the commercialization of microalgae cultivation is due to the high costs of nutrients such as carbon, phosphorous, and nitrogen. Meanwhile, the organic-rich anaerobic digestate which is difficult to be purified by conventional techniques is appropriate to be used as a low-cost nutrient source for the economic viability and sustainability of microalgae production. This option is also beneficial in terms of reutilize the organic fraction of solid waste instead of discarded as zero-value waste. Anaerobic digestate is the side product of biogas production during anaerobic digestion process, where optimum nutrients are needed to satisfy the physiological needs to grow microalgae. Besides, the turbidity, competing biological contaminants, ammonia and metal toxicity of the digestate are also potentially contributing to the inhibition of microalgae growth. Thus, this review is aimed to explicate the feasibility of utilizing the anaerobic digestate to cultivate microalgae by evaluating their potential challenges and solutions. The proposed potential solutions (digestate dilution and pre-treatment, microalgae strain selection, extra organics addition, nitrification and desulfurization) corresponding to the state-of-the-art challenges are applicable as future directions of the research.
Hydrolysis kinetics for solubilizing waste activated sludge at low temperature thermal treatment derived from multivariate non-linear model

Liew CS, Raksasat R, Rawindran H, Kiatkittipong W, Lim JW, Leong WH, et al.

Chemosphere, 2022 Apr;292:133478.
PMID: 34979202 DOI: 10.1016/j.chemosphere.2021.133478

Low temperature thermal pre-treatment is a low-cost method to break down the structure of extracellular polymeric substances in waste activated sludge (WAS) while improving the sludge biodegradability. However, previous models on low temperature thermal pre-treatment did not adequately elucidate the behaviour of sludge hydrolysis process for the duration ranging from 5 to 9 h. Therefore, this work had developed an inclusive functional model to describe the kinetics of sludge hydrolysis for a wide range of treatment conditions (30 °C-90 °C within 0 and 16 h). As compared with treatment duration, the treatment temperature played a greater impact in solubilizing WAS. Accordingly, the 90 °C treatment had consistently produced WAS with the highest degree of solubility. Nonetheless, the mediocre discrepancies between 90 °C and 75 °C may challenge the practicality of increasing the treatment temperatures beyond 75 °C. The effects of treatment duration on soluble chemical oxygen demand, soluble carbohydrate and soluble protein were only significant during the first 4 h, except for humic substances release that continued to increase with treatment duration. Finally, a good fit with R2 > 0.95 was achieved using an inclusive multivariate non-linear model, substantiating the functionality to predict the kinetics of sludge hydrolysis at arbitrary treatment conditions.
Biomass-derived carbon-based and silica-based materials for catalytic and adsorptive applications- An update since 2010

Chen K, Ng KH, Cheng CK, Cheng YW, Chong CC, Vo DN, et al.

Chemosphere, 2022 Jan;287(Pt 2):132222.
PMID: 34826917 DOI: 10.1016/j.chemosphere.2021.132222

Biomass, which defined as plant- or animal-based materials, is intriguing tremendous scientific attentions due to its renewable attribute in serving energy security. Amongst, the plant-based biomasses, particularly those that co-generated in the agriculture activities, are commonly regarded as fuel for burning, which overlooked their hidden potentials for high-end applications. Organically, the plant-based biomass constitutes of lignocellulose components, which can be served as promising precursors for functionalized carbon materials. Meanwhile, its inorganic counterpart made up of various minerals, with Si being the most concerned one. With the advancement of biomass technologies and material synthesis in recent years, numerous attempts were endeavoured to obtain valorised products from biomass. Particularly, syntheses of catalytic and adsorptive materials are actively researched in the field of biomass reutilization. Herein, our work systematically summarized the advancements of biomass-materials for these applications in recent 10 years (2010-2020), with a special focus on the carbon-based and Si-based catalytic/adsorptive materials. Significantly, the deriving steps, inclusive of both pre-treatment and post-treatment of such materials, are incorporated in the discussion, alongside with their significances revealed too. The performance of the as-obtained materials in the respective application is systematically correlated to their physicochemical properties, hence providing valuable insights to the readers. Challenges and promising directions to be explored are raised too at the end of the review, aiming to advocate better-usage of biomass while offering great opportunities to sustain catalysis and adsorption in the industrial scale.
Long-term evaluation of palm oil mill effluent (POME) steam reforming over lanthanum-based perovskite oxides

Cheng YW, Chong CC, Cheng CK, Wang CH, Ng KH, Witoon T, et al.

J Environ Manage, 2024 Feb;351:119919.
PMID: 38157572 DOI: 10.1016/j.jenvman.2023.119919

To replace the obsolete ponding system, palm oil mill effluent (POME) steam reforming (SR) over net-acidic LaNiO3 and net-basic LaCoO3 were proposed as the POME primary treatments, with promising H2-rich syngas production. Herein, the long-term evaluation of POME SR was scrutinized with both catalysts under the optimal conditions (600 °C, 0.09 mL POME/min, 0.3 g catalyst, & 74-105 μm catalyst particle size) to examine the catalyst microstructure changes, transient process stability, and final effluent evaluation. Extensive characterization proved the (i) adsorption of POME vapour on catalysts before SR, (ii) deposition of carbon and minerals on spent SR catalysts, and (iii) dominance of coking deactivation over sintering deactivation at 600 °C. Despite its longer run, spent LaCoO3 (50.54 wt%) had similar carbon deposition with spent LaNiO3 (50.44 wt%), concurring with its excellent coke resistance. Spent LaCoO3 (6.12 wt%; large protruding crystals) suffered a harsher mineral deposition than spent LaNiO3 (3.71 wt%; thin film coating), confirming that lower reactivity increased residence time of reactants. Transient syngas evolution of both SR catalysts was relatively steady up to 4 h but perturbed by coking deactivation thereafter. La2O2CO3 acted as an intermediate species that hastened the coke removal via reverse Boudouard reaction upon its decarbonation. La2O2CO3 decarbonation occurred continuously in LaCoO3 system but intermittently in LaNiO3 system. LaNiO3 system only lasted for 13 h as its compact ash blocked the gas flow. LaCoO3 system lasted longer (17 h) with its porous ash, but it eventually failed because KCl crystallites blocked its active sites. Relatively, LaCoO3 system offered greater net H2 production (72.78%) and POME treatment volume (30.77%) than LaNiO3 system. SR could attain appreciable POME degradation (>97% COD, BOD5, TSS, & colour intensity). Withal, SR-treated POME should be polished to further reduce its incompliant COD and BOD5.
Engineering pyrolysis biochar via single-step microwave steam activation for hazardous landfill leachate treatment

Lam SS, Yek PNY, Ok YS, Chong CC, Liew RK, Tsang DCW, et al.

J Hazard Mater, 2020 05 15;390:121649.
PMID: 31753673 DOI: 10.1016/j.jhazmat.2019.121649

Improving the sustainability and cost-effectiveness of biochar production is crucial to meet increased global market demand. Here, we developed a single-step microwave steam activation (STMSA) as a simplified yet efficient method to produce microwave activated biochar (MAB) from waste palm shell (WPS). The STMSA recorded a higher heating rate (70 °C/min) and higher conversion (45 wt%) of WPS into highly microporous MAB (micropore surface area of 679.22 m2/g) in contrast with the conventional heating approach (≤ 12-17 wt%). The MAB was then applied as biosorbent for hazardous landfill leachate (LL) treatment and the adsorption performance was compared with commercial activated carbon under different pH, adsorbent quantity, adsorbate concentrations, and contact times. The MAB demonstrated high adsorption capacity, achieving maximum adsorption efficiency at 595 mg/g and 65 % removal of chemical oxygen demand (COD) with 0.4 g/L of adsorbent amount under optimal acidic conditions (pH ≈ 2-3) after 24 h of contact time. The Freundlich isotherm and pseudo second-order kinetic models were well-fitted to explain the equilibrium adsorption and kinetics. The results indicate the viability of STMSA as a fast and efficient approach to produce activated biochar as a biosorbent for the treatment of hazardous landfill leachate.
Positive Hepatitis B Core Antibody Is Associated With Cirrhosis and Hepatocellular Carcinoma in Nonalcoholic Fatty Liver Disease

Chan TT, Chan WK, Wong GL, Chan AW, Nik Mustapha NR, Chan SL, et al.

Am J Gastroenterol, 2020 06;115(6):867-875.
PMID: 32149781 DOI: 10.14309/ajg.0000000000000588

OBJECTIVES: Previous exposure to hepatitis B virus (HBV) may increase the risk of hepatocellular carcinoma (HCC) in patients with chronic hepatitis C. We aim to study the impact of previous HBV infection on the severity and outcomes of patients with nonalcoholic fatty liver disease (NAFLD).
METHODS: This was a multicenter study of 489 patients with biopsy-proven NAFLD and 69 patients with NAFLD-related or cryptogenic HCC. Antihepatitis B core antibody (anti-HBc) was used to detect the previous HBV infection.
RESULTS: In the biopsy cohort, positive anti-HBc was associated with lower steatosis grade but higher fibrosis stage. 18.8% and 7.5% of patients with positive and negative anti-HBc had cirrhosis, respectively (P < 0.001). The association between anti-HBc and cirrhosis remained significant after adjusting for age and metabolic factors (adjusted odds ratio 2.232; 95% confidence interval, 1.202-4.147). At a mean follow-up of 6.2 years, patients with positive anti-HBc had a higher incidence of HCC or cirrhotic complications (6.5% vs 2.2%; P = 0.039). Among patients with NAFLD-related or cryptogenic HCC, 73.9% had positive anti-HBc. None of the patients had positive serum HBV DNA. By contrast, antihepatitis B surface antibody did not correlate with histological severity.
DISCUSSION: Positive anti-HBc is associated with cirrhosis and possibly HCC and cirrhotic complications in patients with NAFLD. Because a significant proportion of NAFLD-related HCC may develop in noncirrhotic patients, future studies should define the role of anti-HBc in selecting noncirrhotic patients with NAFLD for HCC surveillance.
Fulltext Defining the endoscopic ultrasound features of chronic pancreatitis in Asians: a multicenter validation study

Koh CJ, Lakhtakia S, Kida M, Lesmana CRA, Ang TL, Vu CKF, et al.

Endoscopy, 2021 06;53(6):595-602.
PMID: 32650341 DOI: 10.1055/a-1217-3112

BACKGROUND: Although endoscopic ultrasound (EUS) features and criteria have been described in chronic pancreatitis, challenges remain with interoperator variability and ease of adoption. The aim of this study was to define and validate the EUS features of chronic pancreatitis in a multicenter prospective study in Asia.
METHOD: The study was divided into two parts: the first part was conducted to derive the EUS features of chronic pancreatitis with adequate interoperator agreement; the second was to prospectively evaluate these features in a multicenter cross-sectional study and determine the optimal combination of features for the diagnosis of chronic pancreatitis. Prospectively enrolled cases had standard internationally validated radiologic or histologic features of chronic pancreatitis, and controls were patients without chronic pancreatitis who underwent EUS examination.
RESULTS: The top six EUS features that had good interobserver agreement (mean kappa 0.73, range 0.60 - 0.90) were selected to be further evaluated in part II of the study. These included: hyperechoic foci with shadowing, lobularity with honeycombing, cysts, dilated main pancreatic duct, dilated side branches, and calculi in the main pancreatic duct. A total of 284 subjects (132 cases, 152 controls) were enrolled from 12 centers in Asia. All six features had high accuracy ranging from 63.3 % to 89.1 %. Two or more of these six EUS features accurately defined chronic pancreatitis (sensitivity 94.7 %, specificity 98.0 %), with an area under the receiver operating curve of 0.986.
CONCLUSION: This multicenter Asian study characterized and defined the EUS features of chronic pancreatitis. This provides a useful tool in clinical practice and further research in pancreatic cancer surveillance.