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Recent Advances in the Application of Inorganic Salt Pretreatment for Transforming Lignocellulosic Biomass into Reducing Sugars

Loow YL, Wu TY, Tan KA, Lim YS, Siow LF, Jahim JM, et al.

J Agric Food Chem, 2015 Sep 30;63(38):8349-63.
PMID: 26325225 DOI: 10.1021/acs.jafc.5b01813

Currently, the transformation of lignocellulosic biomass into value-added products such as reducing sugars is garnering attention worldwide. However, efficient hydrolysis is usually hindered by the recalcitrant structure of the biomass. Many pretreatment technologies have been developed to overcome the recalcitrance of lignocellulose such that the components can be reutilized more effectively to enhance sugar recovery. Among all of the utilized pretreatment methods, inorganic salt pretreatment represents a more novel method and offers comparable sugar recovery with the potential for reducing costs. The use of inorganic salt also shows improved performance when it is integrated with other pretreatment technologies. Hence, this paper is aimed to provide a detailed overview of the current situation for lignocellulosic biomass and its physicochemical characteristics. Furthermore, this review discusses some recent studies using inorganic salt for pretreating biomass and the mechanisms involved during the process. Finally, some prospects and challenges using inorganic salt are highlighted.
Fulltext Usage of traditional and complementary medicine (T & CM): Prevalence, practice and perception among post stroke patients attending conventional stroke rehabilitation in a teaching hospital in Malaysia

Ali MF, Abdul Aziz AF, Rashid MR, Che Man Z, Amir AA, Lim YS, et al.

Med J Malaysia, 2015 Feb;70(1):18-23.
PMID: 26032524

INTRODUCTION: The lack of evidence that proves the benefit of traditional and complementary medicines (T & CM) in treating chronic medical conditions does not deter its usage among patients worldwide. Prevalence of usage among post-stroke patients in Malaysia especially is unknown. This study aims to determine the prevalence, practice and perception of T & CM use among stroke survivors attending an outpatient rehabilitation program in a teaching hospital.
METHODS: A cross-sectional study was conducted among 104 post stroke patients attending an outpatient rehabilitation program. A structured self-administered questionnaire was used to collect data on sociodemographic and clinical profile of patients, as well as types of therapy used and perception on T & CM usage. Descriptive analysis was done, and bivariate analysis was used to determine associations between categorical data.
RESULTS: Mean age of patients was 62 years (SD 12.2), 54% were Chinese and 75% of the patients had ischaemic stroke. Mean age of T & CM users was younger compared to non- T & CM users (61 years vs. 66 years, p=0.04). Two-thirds (66%) of patients admitted to concurrent T & CM usage while attending conventional post stroke rehabilitation. Acupuncture (40.4%), massage (40.4%) and traditional Chinese medicine (11.5%) were the most common T & CM used. Positive perception was recorded in terms of ability of T & CM usage to relieve post stroke symptoms (68%), and it was safe to use because it was made from 'natural sources'. Negative perception recorded: T & CM caused significant adverse effects (57.6%) and was not safe to be used in combination with other conventional medicines (62.5%).
CONCLUSIONS: Concurrent T & CM usage among post-stroke patients attending structured outpatient rehabilitation program is widely practised especially acupuncture, massage and traditional Chinese medicines. Overall the perception towards its use is favourable.
Study site: Medical Rehabilitation Services Department, Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
The Choice of Population and Outcomes in Neonatal Trials on Hyperbilirubinemia: Are They Relevant? An Analysis of Cochrane Neonatal Reviews

Lai NM, Lee SWH, Wai SX, Teh ZW, Chan MY, Lim YS, et al.

Neonatology, 2020;117(6):687-693.
PMID: 33264799 DOI: 10.1159/000511656

BACKGROUND: Neonates with jaundice are usually managed according to their serum bilirubin despite an unclear overall correlation between bilirubin levels and patient-important outcomes (PIOs) such as kernicterus spectrum disorder (KSD).
OBJECTIVES: We examined data from Cochrane Neonatal reviews to assess whether conditions that constituted KSD were included as key outcomes and how commonly they occurred in the population studied.
METHODS: We identified Cochrane reviews, published till November 2017 that evaluated interventions for neonatal jaundice (NNJ). We extracted the following information at the review and study levels: included population, outcomes assessed (in particular, whether PIOs such as KSD were listed as the primary outcomes), as well as their cumulative incidence in the reviews.
RESULTS: Out of 311 reviews, 11 evaluated interventions for NNJ with 78 randomized controlled trials (RCTs) included. Among the reviews, a total number of 148 outcomes were predefined and 30 (20.3%) were PIOs related to KSD, with 11 (36.7%) listed as primary outcomes. Among the 78 included RCTs (total participants = 8,232), 38 (48.7%) enrolled predominantly high-risk and 40 (51.3%) enrolled predominantly low-risk population. A total number of 431 outcomes were reported, and 40 (9.2%) were PIOs related to KSD (of which 37 were from studies with high-risk infants), with 13 (32.5%) listed as primary outcome. Cumulatively, no infant developed KSD across all studies.
CONCLUSIONS: There is suboptimal representation of PIOs such as KSD in neonatal trials and Cochrane reviews on NNJ. Over half of the trials included populations with very low risk of KSD, which does not represent judicious use of resources. Amidst our continued search for a more reliable surrogate marker for NNJ, studies should evaluate the whole spectrum KSD alongside serum bilirubin in high-risk populations with sufficiently significant event rates, as this will make the trial methodologically feasible, with findings that will impact the population concerned.
Comparison of Clinical Outcomes Among Deceased Donor Kidney Transplant Recipients Before and After Utilizing Estimated Posttransplant Survival Score for Kidneys Allocation in Malaysia

Ng YM, Lim YS, Ee LW, Fong VK, Low CL, Yee SY, et al.

Transplant Proc, 2022 Jan 29.
PMID: 35105465 DOI: 10.1016/j.transproceed.2022.01.002

BACKGROUND: The Malaysian Kidney Allocation System implemented in 2020 includes only kidney transplant candidates with estimated posttransplant survival (EPTS) score of ≤20%, in replacement of Malaysian Organs Sharing System, which was based solely on dialysis vintage. We aim to compare the clinical outcomes of deceased-donor kidney transplant recipients (DDKTRs) with EPTS ≤20% to those with EPTS >20%.
METHODS: All DDKTRs between January 1, 2015, and December 29, 2020, were included and categorized into 2 groups: EPTS ≤20% and EPTS >20%. Cox regression was performed to evaluate the association of EPTS score and patient survival. The rate of postoperative complications, graft failure and patient survival were compared between 2 groups. Data were analyzed with SPSS v26 and R v4.0.4. The study complies with the Helsinki Congress and the Istanbul Declaration.
RESULTS: We included 159 DDKTRs, with a median follow-up of 25 months (range, 10-60 months). The mean age of those with EPTS ≤20% was 32.2 ± 3.4 years and those with EPTS >20% was 46.0 ± 6.7 years, and the median EPTS score were 16% (range, 12%-18%) and 38% (range, 27%-56.5%), respectively. EPTS score was associated with patient survival (hazard ratio, 1.031; 95% CI 1.010-1.052; P = .003), and the cutoff points of 30% and above were associated with worse survival. It showed good discrimination (C-index, 0.729; 95% CI 0.579-0.878; P = .003) and the optimal cutoff value was 38% (65.5% sensitivity, 68.8% specificity, 17.8% positive predictive value, and 95.8% negative predictive value). Both groups had similar rate of surgical complications (P = .191), graft failure (P = .503), and patient survival (P = .654), but those with EPTS >20% had higher incidence of urinary tract infection (9.3% vs 27.6%, P = .016).
CONCLUSIONS: There was no difference in clinical outcomes using an EPTS cutoff point of 20% but worse patient survival if higher cutoff point was used.
Gold-silver@TiO2 nanocomposite-modified plasmonic photoanodes for higher efficiency dye-sensitized solar cells

Lim SP, Lim YS, Pandikumar A, Lim HN, Ng YH, Ramaraj R, et al.

Phys Chem Chem Phys, 2017 Jan 04;19(2):1395-1407.
PMID: 27976767 DOI: 10.1039/c6cp05950c

In the present investigation, gold-silver@titania (Au-Ag@TiO2) plasmonic nanocomposite materials with different Au and Ag compositions were prepared using a simple one-step chemical reduction method and used as photoanodes in high-efficiency dye-sensitized solar cells (DSSCs). The Au-Ag incorporated TiO2 photoanode demonstrated an enhanced solar-to-electrical energy conversion efficiency of 7.33%, which is ∼230% higher than the unmodified TiO2 photoanode (2.22%) under full sunlight illumination (100 mW cm-2, AM 1.5G). This superior solar energy conversion efficiency was mainly due to the synergistic effect between the Au and Ag, and their surface plasmon resonance effect, which improved the optical absorption and interfacial charge transfer by minimizing the charge recombination process. The influence of the Au-Ag composition on the overall energy conversion efficiency was also explored, and the optimized composition with TiO2 was found to be Au75-Ag25. This was reflected in the femtosecond transient absorption dynamics in which the electron-phonon interaction in the Au nanoparticles was measured to be 6.14 ps in TiO2/Au75:Ag25, compared to 2.38 ps for free Au and 4.02 ps for TiO2/Au100:Ag0. The slower dynamics indicates a more efficient electron-hole separation in TiO2/Au75:Ag25 that is attributed to the formation of a Schottky barrier at the interface between TiO2 and the noble metal(s) that acts as an electron sink. The significant boost in the solar energy conversion efficiency with the Au-Ag@TiO2 plasmonic nanocomposite showed its potential as a photoanode for high-efficiency DSSCs.
Fulltext Use of Composite Outcomes in Neonatal Trials: An Analysis of the Cochrane Reviews

Lai NM, Yap AQY, Ong HC, Wai SX, Yeo JHH, Koo CYE, et al.

Neonatology, 2021;118(3):259-263.
PMID: 33780936 DOI: 10.1159/000514402

INTRODUCTION: Composite outcomes are used to increase the power of a study by combining event rates. Many composite outcomes in adult clinical trials have components that differ substantially in patient importance, event rate, and effect size, making interpretation challenging. Little is known about the use of composite outcomes in neonatal randomized controlled trials (RCTs).
METHODS: We assessed the use of composite outcomes in neonatal RCTs included in Cochrane Neonatal reviews published till November 2017. Two authors reviewed the components of the composite outcomes to compare their patient importance and computed the ratios of effect sizes and event rates between the components, with an a priori threshold of 1.5, indicating a substantial difference. Descriptive statistics were presented.
RESULTS: We extracted 7,766 outcomes in 2,134 RCTs in 312 systematic reviews. Among them, 55 composite outcomes (0.7%) were identified in 46 RCTs. The vast majority (92.7%) of composite outcomes had 2 components, with death being the most common component (included 51 times [92.7%]). The components in nearly three-quarters of the composite outcomes (n = 40 [72.7%]) had different patient importance, while the effect sizes and event rates differed substantially between the components in 27 (49.1%) and 35 (63.6%) outcomes, respectively, with up to 43-fold difference in the event rates observed.
CONCLUSIONS: The majority of composite outcomes in neonatal RCTs had different patient importance with contrasting effect sizes and event rates between the components. In patient communication, clinicians should highlight individual components, rather than the composites, with explanation on the relationship between the components, to avoid misleading impression on the effect of the intervention. Future trials should report the estimates of all individual components alongside the composite outcomes presented.