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Harvesting of microalgae biomass from the phycoremediation process of greywater

Atiku H, Mohamed RMSR, Al-Gheethi AA, Wurochekke AA, Kassim AHM

Environ Sci Pollut Res Int, 2016 12;23(24):24624-24641.
PMID: 27544526 DOI: 10.1007/s11356-016-7456-9

The wide application of microalgae in the field of wastewater treatment and bioenergy source has improved research studies in the past years. Microalgae represent a good source of biomass and bio-products which are used in different medical and industrial activities, among them the production of high-valued products and biofuels. The present review focused on greywater treatment through the application of phycoremediation technique with microalgae and presented recent advances in technologies used for harvesting the microalgae biomass. The advantages and disadvantages of each method are discussed. The microbiological aspects of production, harvesting and utilization of microalgae biomass are viewed.
Fulltext Diet Gut Microbiota Axis in Pregnancy: A Systematic Review of Recent Evidence

Kunasegaran T, Balasubramaniam VRMT, Arasoo VJT, Palanisamy UD, Ramadas A

Curr Nutr Rep, 2023 Mar;12(1):203-214.
PMID: 36810808 DOI: 10.1007/s13668-023-00453-4

PURPOSE OF REVIEW: Although gut microbiota have been associated with the etiology of some diseases, the influence of foods on gut microbiota, especially among pregnant women, remains unclear. Hence, a systematic review was performed to investigate the association between diet and gut microbiota and their influence on metabolic health in pregnant women.
RECENT FINDINGS: We performed the systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 protocol to investigate the association between diet and gut microbiota and their influence on metabolic role in pregnant women. Five databases were searched for relevant peer-reviewed articles published in English since 2011. Two-staged screening of 659 retrieved records resulted in the inclusion of 10 studies. The collated findings suggested associations between nutrient intakes and four key microbes: Collinsella, Lachnospira, Sutterella, Faecalibacterium, and the Firmicutes/Bacteroidetes ratio in pregnant women. Dietary intakes in pregnancy were found to modify the gut microbiota and positively influence the cell metabolism in pregnant women. This review, however, emphasizes the importance of conducting well-designed prospective cohorts to investigate the role of changes in dietary intakes within the pregnancy and the influence of such changes on gut microbiota.
Fulltext Unlocking the Potential of Lignocellulosic Biomass Dragon Fruit (Hylocereus polyrhizus) in Bioplastics, Biocomposites and Various Commercial Applications

Taharuddin NH, Jumaidin R, Mansor MR, Hazrati KZ, Tarique J, Asyraf MRM, et al.

Polymers (Basel), 2023 Jun 12;15(12).
PMID: 37376300 DOI: 10.3390/polym15122654

Dragon fruit, also called pitaya or pitahaya, is in the family Cactaceae. It is found in two genera: 'Selenicereus' and 'Hylocereus'. The substantial growth in demand intensifies dragon fruit processing operations, and waste materials such as peels and seeds are generated in more significant quantities. The transformation of waste materials into value-added components needs greater focus since managing food waste is an important environmental concern. Two well-known varieties of dragon fruit are pitaya (Stenocereus) and pitahaya (Hylocereus), which are different in their sour and sweet tastes. The flesh of the dragon fruit constitutes about two-thirds (~65%) of the fruit, and the peel is approximately one-third (~22%). Dragon fruit peel is believed to be rich in pectin and dietary fibre. In this regard, extracting pectin from dragon fruit peel can be an innovative technology that minimises waste disposal and adds value to the peel. Dragon fruit are currently used in several applications, such as bioplastics, natural dyes and cosmetics. Further research is recommended for diverging its development in various areas and maturing the innovation of its usage.
Fulltext Potential of Natural Fiber Reinforced Polymer Composites in Sandwich Structures: A Review on Its Mechanical Properties

Alsubari S, Zuhri MYM, Sapuan SM, Ishak MR, Ilyas RA, Asyraf MRM

Polymers (Basel), 2021 Jan 28;13(3).
PMID: 33525703 DOI: 10.3390/polym13030423

The interest in using natural fiber reinforced composites is now at its highest. Numerous studies have been conducted due to their positive benefits related to environmental issues. Even though they have limitations for some load requirements, this drawback has been countered through fiber treatment and hybridization. Sandwich structure, on the other hand, is a combination of two or more individual components with different properties, which when joined together can result in better performance. Sandwich structures have been used in a wide range of industrial material applications. They are known to be lightweight and good at absorbing energy, providing superior strength and stiffness-to-weight ratios, and offering opportunities, through design integration, to remove some components from the core element. Today, many industries use composite sandwich structures in a range of components. Through good design of the core structure, one can maximize the strength properties, with a low density. However, the application of natural fiber composites in sandwich structures is still minimal. Therefore, this paper reviewed the possibility of using a natural fiber composite in sandwich structure applications. It addressed the mechanical properties and energy-absorbing characteristics of natural fiber-based sandwich structures tested under various compression loads. The results and potential areas of improvement to fit into a wide range of engineering applications were discussed.
Potentiality of MWCNT on 3D-printed bio-inspired spherical-roof cubic core under quasi-static loading

Ma Q, Rejab MRM, Hassan SA, Hu H, Kumar AP

J Mech Behav Biomed Mater, 2022 Dec;136:105514.
PMID: 36215770 DOI: 10.1016/j.jmbbm.2022.105514

Sandwich panel is increasingly used as lightweight energy absorbing components, which provides excellent crashworthiness performance with the three-dimensional periodic core. This paper investigates 3D-printed bio-inspired spherical-roof cubic cores with multi-walled carbon nanotubes (MWCNT) and foam-filled cores under quasi-static loading. The proposed bio-inspired spherical-roof cubic cores with 1.5 mm wall thickness were manufactured using the fused filament fabrication process, which used 70% polylactic acid (PLA) and 30% carbon fiber filament. Moreover, four groups of 3D-printed bio-inspired spherical-roof cubic cores were compared and analyzed on compressive properties and failure behavior. Experimental results were shown that foam-filled double bio-inspired spherical-roof cubic core with MWCNT was the maximum Fpeak with 1.92 kN, which provided a much more stable plateau load and better energy-absorbing characteristics. In addition, it is conducted that a double bio-inspired spherical-roof cubic core with four notches core is considered as the potential energy-absorbing core.
Fulltext Diet, lifestyle and gut microbiota composition among Malaysian women with gestational diabetes mellitus: a prospective cohort study

Kunasegaran T, Balasubramaniam VRMT, Thirunavuk Arasoo VJ, Palanisamy UD, Tan YK, Ramadas A

Sci Rep, 2024 Mar 22;14(1):6891.
PMID: 38519592 DOI: 10.1038/s41598-024-57627-5

The study addressed a significant gap in the profiling and understanding of the gut microbiota's influence on Malaysian Malay women with gestational diabetes mellitus (GDM). This prospective cohort study aimed to explore the intricate relationship between gut microbiota, dietary choices, and lifestyle factors among Malay women, both with and without GDM. The research specifically focused on participants during the second (T0) and third (T1) trimesters of pregnancy in Johor Bahru, Malaysia. In Part 1 of the study, a diverse pool of pregnant women at T0 was categorized into two groups: those diagnosed with GDM and those without GDM, with a total sample size of 105 individuals. The assessments encompassed demographic, clinical, lifestyle, and dietary factors at the T0 and T1 trimesters. Part 2 of the study delved into microbiome analysis, targeting a better understanding of the gut microbiota among the participants. Stool samples were randomly collected from 50% of the individuals in each group (GDM and non-GDM) at T0 and T1. The collected samples underwent processing, and 16s rRNA metagenomic analysis was employed to study the microbial composition. The results suggested an association between elevated body weight and glucose levels, poor sleep quality, lack of physical activity, greater intake of iron and meat, and reduced fruit consumption among women with GDM compared to non-GDM groups. The microbiome analysis revealed changes in microbial composition over time, with reduced diversity observed in the GDM group during the third trimester. The genera Lactiplantibacillus, Parvibacter, Prevotellaceae UCG001, and Vagococcus positively correlated with physical activity levels in GDM women in the second trimester. Similarly, the genus Victivallis exhibited a strong positive correlation with gravida and parity. On the contrary, the genus Bacteroides and Roseburia showed a negative correlation with omega-3 polyunsaturated fatty acids (PUFAs) in women without GDM in the third trimester. The study highlighted the multifaceted nature of GDM, involving a combination of lifestyle factors, dietary choices, and changes in gut microbiota composition. The findings emphasized the importance of considering these interconnected elements in understanding and managing gestational diabetes among Malaysian Malay women. Further exploration is essential to comprehend the mechanisms underlying this relationship and develop targeted interventions for effective GDM management.
Cgl-SLT2 is required for appressorium formation, sporulation and pathogenicity in Colletotrichum gloeosporioides

Yong HY, Bakar FD, Illias RM, Mahadi NM, Murad AM

Braz J Microbiol, 2013 Dec;44(4):1241-50.
PMID: 24688518

The mitogen-activated protein (MAP) kinase pathways has been implicated in the pathogenicity of various pathogenic fungi and plays important roles in regulating pathogenicity-related morphogenesis. This work describes the isolation and characterization of MAP kinase gene, Cgl-SLT2, from Colletotrichum gloeosporioides. A DNA sequence, including 1,633 bp of Cgl-SLT2 open-reading frame and its promoter and terminator regions, was isolated via DNA walking and cloned. To analyze gene function, a gene disruption cassette containing hygromycin-resistant gene was constructed, and Cgl-SLT2 was inactivated via gene deletion. Analysis on Cgl-slt2 mutant revealed a defect in vegetative growth and sporulation as compared to the wild-type strain. When grown under nutrient-limiting conditions, hyperbranched hyphal morphology was observed in the mutant. Conidia induction for germination on rubber wax-coated hard surfaces revealed no differences in the percentage of conidial germination between the wild-type and Cgl-slt2 mutant. However, the percentage of appressorium formation in the mutant was greatly reduced. Bipolar germination in the mutant was higher than in the wild-type at 8-h post-induction. A pathogenicity assay revealed that the mutant was unable to infect either wounded or unwounded mangoes. These results suggest that the Cgl-SLT2 MAP kinase is required for C. gloeosporioides conidiation, polarized growth, appressorium formation and pathogenicity.
A case study on the source apportionment of indoor air quality at a kindergarten in eastern Peninsular Malaysia using cluster analysis

Sidek SS, Yatim SRM, Abdullah S, Shafie FA, Ishak AR, Dom NC, et al.

Med J Malaysia, 2024 Mar;79(Suppl 1):104-109.
PMID: 38555893

BACKGROUND: Indoor air quality is an important concern for kindergartener because young children are more vulnerable to the effects of poor air quality. Poor indoor air quality can cause respiratory problems and other health issues, which can negatively affect a child's ability to learn and grow. Aim of this study is to determine the trend and status of indoor air pollutants in study areas by using descriptive statistics and cluster analysis.
MATERIALS AND METHODS: Air temperature (T), relative humidity (RH), air movement (AM), carbon dioxide (CO2), formaldehyde (HCHO), and particulate matter (PM) are the monitored parameters. Monitoring was carried out in the kindergarten for three consecutive days starting from 8.00am to 12.00pm.
RESULTS: Indoor carbon dioxide readings were higher at 0800 when parents drove to kindergarten to drop off their children without turning off the engine. In addition to this, the PM10 reading at 1000 was high but still within the standard range according to ICOP-IAQ 2010.
CONCLUSION: The findings highlight the importance of indoor air quality improvement measures for kindergarten buildings which can be used to improve indoor air quality in kindergarten environments.
Neuromuscular effects of candoxin, a novel toxin from the venom of the Malayan krait (Bungarus candidus)

Nirthanan S, Charpantier E, Gopalakrishnakone P, Gwee MC, Khoo HE, Cheah LS, et al.

Br J Pharmacol, 2003 Jun;139(4):832-44.
PMID: 12813007

1 Candoxin (MW 7334.6), a novel toxin isolated from the venom of the Malayan krait Bungarus candidus, belongs to the poorly characterized subfamily of nonconventional three-finger toxins present in Elapid venoms. The current study details the pharmacological effects of candoxin at the neuromuscular junction. 2 Candoxin produces a novel pattern of neuromuscular blockade in isolated nerve-muscle preparations and the tibialis anterior muscle of anaesthetized rats. In contrast to the virtually irreversible postsynaptic neuromuscular blockade produced by curaremimetic alpha-neurotoxins, the neuromuscular blockade produced by candoxin was rapidly and completely reversed by washing or by the addition of the anticholinesterase neostigmine. 3 Candoxin also produced significant train-of-four fade during the onset of and recovery from neuromuscular blockade, both, in vitro and in vivo. The fade phenomenon has been attributed to a blockade of putative presynaptic nicotinic acetylcholine receptors (nAChRs) that mediate a positive feedback mechanism and maintain adequate transmitter release during rapid repetitive stimulation. In this respect, candoxin closely resembles the neuromuscular blocking effects of d-tubocurarine, and differs markedly from curaremimetic alpha-neurotoxins that produce little or no fade. 4 Electrophysiological experiments confirmed that candoxin produced a readily reversible blockade (IC(50) approximately 10 nM) of oocyte-expressed muscle (alphabetagammadelta) nAChRs. Like alpha-conotoxin MI, well known for its preferential binding to the alpha/delta interface of the muscle (alphabetagammadelta) nAChR, candoxin also demonstrated a biphasic concentration-response inhibition curve with a high- (IC(50) approximately 2.2 nM) and a low- (IC(50) approximately 98 nM) affinity component, suggesting that it may exhibit differential affinities for the two binding sites on the muscle (alphabetagammadelta) receptor. In contrast, curaremimetic alpha-neurotoxins have been reported to antagonize both binding sites with equal affinity.
Fulltext Recent Advances, Approaches and Challenges in the Development of Universal Influenza Vaccines

Lim CML, Komarasamy TV, Adnan NAAB, Radhakrishnan AK, Balasubramaniam VRMT

Influenza Other Respir Viruses, 2024 Mar;18(3):e13276.
PMID: 38513364 DOI: 10.1111/irv.13276

Every year, influenza virus infections cause significant morbidity and mortality worldwide. They pose a substantial burden of disease, in terms of not only health but also the economy. Owing to the ability of influenza viruses to continuously evolve, annual seasonal influenza vaccines are necessary as a prophylaxis. However, current influenza vaccines against seasonal strains have limited effectiveness and require yearly reformulation due to the virus undergoing antigenic drift or shift. Vaccine mismatches are common, conferring suboptimal protection against seasonal outbreaks, and the threat of the next pandemic continues to loom. Therefore, there is a great need to develop a universal influenza vaccine (UIV) capable of providing broad and durable protection against all influenza virus strains. In the quest to develop a UIV that would obviate the need for annual vaccination and formulation, a multitude of strategies is currently underway. Promising approaches include targeting the highly conserved epitopes of haemagglutinin (HA), neuraminidase (NA), M2 extracellular domain (M2e) and internal proteins of the influenza virus. The identification and characterization of broadly neutralizing antibodies (bnAbs) targeting conserved regions of the viral HA protein, in particular, have provided important insight into novel vaccine designs and platforms. This review discusses universal vaccine approaches presently under development, with an emphasis on those targeting the highly conserved stalk of the HA protein, recent technological advancements used and the future prospects of a UIV in terms of its advantages, developmental obstacles and potential shortcomings.
Isodose mapping of terrestrial gamma radiation in Sarawak-Borneo: Insights from surface-weathered soil analysis

Idris HN, Sanusi MSM, Ramli AT, Solleh MRM, Yahaya F, Ya'cob MZ, et al.

Appl Radiat Isot, 2024 Jul;209:111327.
PMID: 38642443 DOI: 10.1016/j.apradiso.2024.111327

Presentation of baseline data on terrestrial gamma radiation (TGR) levels is crucial for assessing the annual effective dose received by the public due to natural radiation exposure. Cumulative doses from various sources can become significant, warranting a spatial understanding of TGR distribution. Few countries have comprehensively mapped TGR on a national scale, often facing challenges due to remote or inaccessible regions. This study investigated the influence of weathered soil groups on TGR dose rates in Sarawak-Borneo, Malaysia, to facilitate insights for TGR projection and isodose mapping. A total of 1044 TGR dose rate measurements were collected using NaI (Tl) scintillation detector survey meters, with a mean of 100 nGy h-1 and a range of 8-375 nGy h-1. Non-parametric statistical analyses of variance using Welch's ANOVA, Brown-Forsythe, and Kruskal-Wallis validated (P-sig.=.000) notable dissimilarities among six categories of superficial-weathered soil. Graphical analysis using Sinclair's cumulative plot revealed deviations at intervals of 50, 80, 100, 120, 175, and 205 nGy h-1. These deviations indicate distinct lithological influences. Skeletal soil (entisols) and podzolic soils had high mean dose rates (148 and 113 nGy h-1, respectively) due to limited development, thus preserving abundant uranium (U) and thorium (Th). Meanwhile, gleysols and thionic soils exhibited compatible means (90 and 82 nGy h-1, respectively), while alluvial (or transported soils) and organic soils displayed lower dose rate ranges (mean of 76 and 47 nGy h-1, respectively), reflecting rapid hydrolysis weathering processes. Simple linear regression analysis revealed a strong relationship between TGR dose rate and mean value of weathered soil groups (y = 0.851x + 0.141 nGy h-1), signifying the significance and magnitude of weathered soil groups' impact on TGR dose rates. The obtained R-value is 0.704, indicating a strong linear correlation among soil group variables, and a Durbin-Watson statistic of 1.41, suggesting positive autocorrelation among residuals, thus positive relationships. An isodose map was successfully developed using the Kriging technique, aligning with lithological features of the study area. Semivariogram analysis reveals spatial dependence within a range of 1.47°, supporting the Kriging technique's suitability for spatial inference. In conclusion, this study has successfully revealed the relationship between TGR dose rates and superficial-weathered soil in Sarawak-Borneo. While the linear relationship is applicable to the Sundaland-Borneo tectonic block, it has potential to be used as a valuable tool for spatial inference of TGR dose rates in isodose development with similar lithologial characteristics, aiding in radiation exposure assessment and environmental monitoring.
Recent advances in sago (Metroxylon sagu) fibres, biopolymers, biocomposites, and their prospective applications in industry: A comprehensive review

Al-Fakih GOA, Ilyas RA, Huzaifah MRM, El-Shafay AS

Int J Biol Macromol, 2024 May 04;269(Pt 1):132045.
PMID: 38710254 DOI: 10.1016/j.ijbiomac.2024.132045

Escalating petroleum depletion and environmental crises linked to conventional plastics have fueled interest in eco-friendly alternatives. Natural fibres and biopolymers are garnering increasing attention due to their sustainability. The sago palm (Metroxylon sagu), a tropical tree, holds potential for such materials, with cellulose-rich fibres (42.4-44.12 %) showcasing strong mechanics. Extracted sago palm starch can be blended, reinforced, or plasticised for improved traits. However, a comprehensive review of sago palm fibres, starch, and biocomposites is notably absent. This paper fills this void, meticulously assessing recent advancements in sago palm fibre, cellulose and starch properties, and their eco-friendly composite fabrication. Moreover, it uncovers the latent prospects of sago palm fibres and biopolymers across industries like automotive, packaging, and bioenergy. This review presents a crucial resource for envisaging and realising sustainable materials.
Analysis of Salmonella typhi isolates from Southeast Asia by pulsed-field gel electrophoresis

Thong KL, Puthucheary S, Yassin RM, Sudarmono P, Padmidewi M, Soewandojo E, et al.

J Clin Microbiol, 1995 Jul;33(7):1938-41.
PMID: 7665677

Pulsed-field gel electrophoresis (PFGE) revealed that multiple genetic variants of Salmonella typhi are simultaneously present in Southeast Asia and are associated with sporadic cases of typhoid fever and occasional outbreaks. Comparative analysis of PFGE patterns also suggested that considerable genetic diversity exists among S. typhi strains and that some PFGE patterns are shared between isolates obtained from Malaysia, Indonesia, and Thailand, implying movement of these strains within these regions of Southeast Asia, where they are endemic.
Cross Talk between MicroRNAs and Dengue Virus

Macha NO, Komarasamy TV, Harun S, Adnan NAA, Hassan SS, Balasubramaniam VRMT

Am J Trop Med Hyg, 2024 May 01;110(5):856-867.
PMID: 38579704 DOI: 10.4269/ajtmh.23-0546

Dengue fever (DF) is an endemic infectious tropical disease and is rapidly becoming a global problem. Dengue fever is caused by one of the four dengue virus (DENV) serotypes and is spread by the female Aedes mosquito. Clinical manifestations of DF may range from asymptomatic to life-threatening severe illness with conditions of hemorrhagic fever and shock. Early and precise diagnosis is vital to avoid mortality from DF. A different approach is required to combat DF because of the challenges with the vaccines currently available, which are nonspecific; each is capable of causing cross-reaction and disease-enhancing antibody responses against the residual serotypes. MicroRNAs (miRNAs) are known to be implicated in DENV infection and are postulated to be involved in most of the host responses. Thus, they might be a suitable target for new strategies against the disease. The involvement of miRNAs in cellular activities and pathways during viral infections has been explored under numerous conditions. Interestingly, miRNAs have also been shown to be involved in viral replication. In this review, we summarize the role of known miRNAs, specifically the role of miRNA Let-7c (miR-Let-7c), miR-133a, miR-30e, and miR-146a, in the regulation of DENV replication and their possible effects on the initial immune reaction.
Fulltext Clinico-radiological outcome of Arthroscopic Anterior Cruciate Ligament Reconstruction with Augmentation of Dehydrated Human Amnion Chorion Allograft Membrane using Peroneus Longus Autograft

Tonape PB, Kishore J, Kopparthi RM, Tonape T, Bhamare DS, Desireddy S

Malays Orthop J, 2024 Mar;18(1):33-41.
PMID: 38638668 DOI: 10.5704/MOJ.2403.005

INTRODUCTION: For many sportsmen, anterior cruciate ligament (ACL) tears are unfortunate but common injuries. Several growth factors, cytokine, chemokine, and protease inhibitors functions in stimulation of paracrine reactions in fibroblast, endothelial, and stem cells thereby promoting the tissue restorative processes. Augmented with dehydrated Human Amnion Chorion Membrane (dHACM) allograft reinforces the reconstructed ligament and aids in effective restoration.
MATERIALS AND METHODS: In this case control study 15 patients undertaking ACL reconstruction with tripled peroneus augmented dHACM (G1) were prospectively monitored up for a period of 8 months along with 15 control patients (G2) without dHACM augmentation. Clinical and radiological outcomes were analysed and assessed about effect of augmenting the peroneus longus graft using dHACM. Clinical analysis included pre-operative two, four, six, and eight months post-operative Tegnor-Lysholm score, and radiological analysis included the 6th month postoperative MRI signal-to-noise ratio (SNR) measurements by mean signal-value at femoral insertion, midsubstance and tibial insertion of ACL graft.
RESULTS: Clinically, as a mean Lysholm score of all patients, they were revealed to be consecutively high in G1 than in Group 2 at four, six, and eight months. The signal-to-noise ratio from the MRI results showed majority having good healing in G1 group.
CONCLUSIONS: Based on 6-month MRI, an effective ligamentization (SNR<75) was noticed in 53.33% of patients in the dHACM allograft enhanced group on comparison with 33% in the controls. The overall results show that the augmentation of dHACM allograft to ACL reconstruction yields in good patient outcomes at post-operative follow-up.
Fulltext A comprehensive review on fused deposition modelling of polylactic acid

Sandanamsamy L, Harun WSW, Ishak I, Romlay FRM, Kadirgama K, Ramasamy D, et al.

Prog Addit Manuf, 2022 Oct 31.
PMID: 38625345 DOI: 10.1007/s40964-022-00356-w

Fused Deposition Modelling (FDM) is one of the additive manufacturing (AM) techniques that have emerged as the most feasible and prevalent approach for generating functional parts due to its ability to produce neat and intricate parts. FDM mainly utilises one of the widely used polymers, polylactic acid, also known as polylactide (PLA). It is an aliphatic polyester material and biocompatible thermoplastic, with the best design prospects due to its eco-friendly properties; when PLA degrades, it breaks down into water and carbon dioxide, neither of which are hazardous to the environment. However, PLA has its limitations of poor mechanical properties. Therefore, a filler reinforcement may enhance the characteristics of PLA and produce higher-quality FDM-printed parts. The processing parameters also play a significant role in the final result of the printed parts. This review aims to study and discover the properties of PLA and the optimum processing parameters. This review covers PLA in FDM, encompassing its mechanical properties, processing parameters, characterisation, and applications. A comprehensive description of FDM processing parameters is outlined as it plays a vital role in determining the quality of a printed product. In addition, PLA polymer is highly desirable for various field industrial applications such as in a medical, automobile, and electronic, given its excellent thermoplastic and biodegradability properties.
Electronic Transport and Possible Superconductivity at Van Hove Singularities in Carbon Nanotubes

Yang Y, Fedorov G, Shafranjuk SE, Klapwijk TM, Cooper BK, Lewis RM, et al.

Nano Lett, 2015 Dec 09;15(12):7859-66.
PMID: 26506109 DOI: 10.1021/acs.nanolett.5b02564

Van Hove singularities (VHSs) are a hallmark of reduced dimensionality, leading to a divergent density of states in one and two dimensions and predictions of new electronic properties when the Fermi energy is close to these divergences. In carbon nanotubes, VHSs mark the onset of new subbands. They are elusive in standard electronic transport characterization measurements because they do not typically appear as notable features and therefore their effect on the nanotube conductance is largely unexplored. Here we report conductance measurements of carbon nanotubes where VHSs are clearly revealed by interference patterns of the electronic wave functions, showing both a sharp increase of quantum capacitance, and a sharp reduction of energy level spacing, consistent with an upsurge of density of states. At VHSs, we also measure an anomalous increase of conductance below a temperature of about 30 K. We argue that this transport feature is consistent with the formation of Cooper pairs in the nanotube.
Fulltext Chitosan Nanoparticles for Targeted Cancer Therapy: A Review of Stimuli-Responsive, Passive, and Active Targeting Strategies

Al-Shadidi JRMH, Al-Shammari S, Al-Mutairi D, Alkhudhair D, Thu HE, Hussain Z

Int J Nanomedicine, 2024;19:8373-8400.
PMID: 39161363 DOI: 10.2147/IJN.S472433

Despite all major advancements in drug discovery and development in the pharmaceutical industry, cancer is still one of the most arduous challenges for the scientific community. The implications of nanotechnology have certainly resolved major issues related to conventional anticancer modalities; however, the undesired recognition of nanoparticles (NPs) by the mononuclear phagocyte system (MPS), their poor stability in biological fluids, premature release of payload, and low biocompatibility have restricted their clinical translation. In recent decades, chitosan (CS)-based nanodelivery systems (eg, polymeric NPs, micelles, liposomes, dendrimers, conjugates, solid lipid nanoparticles, etc.) have attained promising recognition from researchers for improving the pharmacokinetics and pharmacodynamics of chemotherapeutics. However, the specialty of this review is to mainly focus on and critically discuss the targeting potential of various CS-based NPs for treatment of different types of cancer. Based on their delivery mechanisms, we classified CS-based NPs into stimuli-responsive, passive, or active targeting nanosystems. Moreover, various functionalization strategies (eg, grafting with polyethylene glycol (PEG), hydrophobic substitution, tethering of stimuli-responsive linkers, and conjugation of targeting ligands) adapted to the architecture of CS-NPs for target-specific delivery of chemotherapeutics have also been considered. Nevertheless, CS-NPs based therapeutics hold great promise for improving therapeutic outcomes while mitigating the off-target effects of chemotherapeutics, a long-term safety profile and clinical testing in humans are warranted for their successful clinical translation.
Nutritional evaluation of working Malay women in Kuala Lumpur as studied by total food duplicate method

Shimbo S, Moon CS, Zhang ZW, Watanabe T, Ismail NH, Ali RM, et al.

Tohoku J Exp Med, 1996 Oct;180(2):99-114.
PMID: 9111760

Nutrient intake was surveyed by the total food duplicate method in 49 adult ethnically Malay women (at the ages of 18 to 47 years and mostly at 30-39 years) working in Kuala Lumpur, Malaysia. Simultaneously, hematological examinations, serum biochemistry, anthropometry and clinical examination were conducted. Nutrient intakes were estimated in reference to the weight of each food item and the standard food composition tables. Lunch was the most substantial meal of the day with rice as a staple food. Compared with the Recommended Dietary Allowance (RDA) values, daily intakes of energy (1,917 kcal as an arithmetic mean), protein (62.2 g), vitamin B1 (0.83 mg) and vitamin B2 (1.18 mg) were sufficient, but intakes of minerals [i.e., calcium (347.8 mg) and iron (12.5 mg)] and some vitamins [i.e., vitamin A (equivalent to 627 micrograms retinol) and niacin (7.84 mg)] were less than RDA. When evaluated on an individual basis, the prevalence of those who took less than 80% RDA was highest for iron (92%), followed by niacin (80%), calcium (57%) and vitamin A (57%). The presence of 7 hypohemoglobinemia cases may be related to the insufficient iron intake. Overweight cases (14 women) were also detected, the prevalence of which increased at advanced ages. Lipid intake was rather high (28% of total food on energy basis), for which the major source was plants with limited contribution from fish/shellfish.
Dengue Virus Infection: Immune Response and Therapeutic Targets

Tin Ern N, Komarasamy TV, Adnan NAA, Balasubramaniam VRMT

Am J Trop Med Hyg, 2024 Nov 12.
PMID: 39531732 DOI: 10.4269/ajtmh.23-0545

Flavivirus infection, especially dengue virus infection caused by DENV, is known to be a significant health concern globally owing to the high incidence and mortality rate. The expanding and increasing disease burden calls for the need to develop an effective treatment and prevent the event of fatal complications, including dengue hemorrhagic fever/dengue shock syndrome. The DENV-induced immune response has been described as paradoxical because it has a protective role in viral clearance but, at the same time, causes more severe infection through viral-specific immunity. This is further complicated by high homology and cross-reactivity between different serotypes of DENV, causing a more severe disease presentation during secondary infection by a heterologous serotype. This serotype complexity poses a challenge for the development of a universal flavivirus vaccine. This review highlights the significance of high motility group box 1 (HMGB1) and nucleotide-binding oligomerization domain, leucine rich repeat and pyrin domain containing 3 (NLRP3) inflammasome activation pathways in initiating an inflammatory response through the downstream activation of nuclear factor κB and proinflammatory cytokine Interleukin (IL)-1B, IL-18 release in DENV infection. It also discusses the role of NLRP3 in activating cellular apoptosis and pyroptosis leading to systemic failure, especially in peripheral tissues. Over the decades, there has been much progress in understanding the immunopathogenesis of DENV infection. Researchers have been studying key pathogenic molecules for potential therapeutic targets including HMGB1 and NLRP3 inflammasome inhibitors, which is explored in this review. Ultimately, although there is not yet an effective antiviral or vaccine for DENV, immunomodulators continue to pave the way to decrease disease severity in infected individuals.

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