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  1. Hussin Y, Aziz MNM, Che Rahim NF, Yeap SK, Mohamad NE, Masarudin MJ, et al.
    Int J Mol Sci, 2018 Apr 11;19(4).
    PMID: 29641445 DOI: 10.3390/ijms19041151
    Extensive research has been done in the search for innovative treatments against colon adenocarcinomas; however, the incidence rate of patients remains a major cause of cancer-related deaths in Malaysia. Natural bioactive compounds such as curcumin have been substantially studied as an alternative to anticancer drug therapies and have been surmised as a potent agent but, nevertheless, remain deficient due to its poor cellular uptake. Therefore, efforts now have shifted toward mimicking curcumin to synthesize novel compounds sharing similar effects. A synthetic analog, (Z)-3-hydroxy-1-(2-hydroxyphenyl)-3-phenylprop-2-ene-1-one (DK1), was recently synthesized and reported to confer improved bioavailability and selectivity toward human breast cancer cells. This study, therefore, aims to assess the anticancer mechanism of DK1 in relation to the induction of in vitro cell death in selected human colon cancer cell lines. Using the3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay, the cytotoxicity of DK1 towards HT29 and SW620 cell lines were investigated. Acridine orange/propidium iodide (AO/PI) dual-staining assay and flow cytometry analyses (cell cycle analysis, Annexin/V-FITC and JC-1 assays) were incorporated to determine the mode of cell death. To further determine the mechanism of cell death, quantitative real-time polymerase chain reaction (qRT-PCR) and proteome profiling were conducted. Results from this study suggest that DK1 induced changes in cell morphology, leading to a decrease in cell viability and subsequent induction of apoptosis. DK1 treatment inhibited cell viability and proliferation 48 h post treatment with IC50 values of 7.5 ± 1.6 µM for HT29 cells and 14.5 ± 4.3 µM for SW620 cells, causing cell cycle arrest with increased accumulation of cell populations at the sub-G₀/G₁phaseof 74% and 23%, respectively. Flow cytometry analyses showed that DK1 treatment in cancer cells induced apoptosis, as indicated by DNA fragmentation and depolarization of the mitochondrial membrane. qRT-PCR results show significant upregulation in the expression of caspase-9 in both HT29 and SW620 cell lines, further supporting that cell death induction by DK1 is via an intrinsic pathway. These outcomes, therefore, demonstrate DK1 as a potential anticancer agent for colon adenocarcinoma due to its anti-apoptotic attributes.
  2. Aziz MNM, Hussin Y, Che Rahim NF, Nordin N, Mohamad NE, Yeap SK, et al.
    Molecules, 2018 Jan 05;23(1).
    PMID: 29303982 DOI: 10.3390/molecules23010075
    Osteosarcoma is one of the primary malignant bone tumors that confer low survival rates for patients even with intensive regime treatments. Therefore, discovery of novel anti-osteosarcoma drugs derived from natural products that are not harmful to the normal cells remains crucial. Curcumin is one of the natural substances that have been extensively studied due to its anti-cancer properties and is pharmacologically safe considering its ubiquitous consumption for centuries. However, curcumin suffers from a poor circulating bioavailability, which has led to the development of a chemically synthesized curcuminoid analog, namely (Z)-3-hydroxy-1-(2-hydroxyphenyl)-3-phenylprop-2-en-1-one (DK1). In this study, the cytotoxic effects of the curcumin analog DK1 was investigated in both U-2OS and MG-63 osteosarcoma cell lines using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay and cell death was microscopically examined via acridine orange/propidium iodide (AO/PI) double staining. Flow cytometer analysis including Annexin V/Fluorescein isothiocyanate (FITC), cell cycle analysis and JC-1 were adapted to determine the mode of cell death. Subsequently in order to determine the mechanism of cell death, quantitative polymerase chain reaction (qPCR) and proteome profiling was carried out to measure the expression of several apoptotic-related genes and proteins. Results indicated that DK1 induced U-2 OS and MG-63 morphological changes and substantially reduced cell numbers through induction of apoptosis. Several apoptotic genes and proteins were steadily expressed after treatment with DK1; including caspase 3, caspase 9, and BAX, which indicated that apoptosis occurred through a mitochondria-dependent signaling pathway. In conclusion, DK1 could be considered as a potential candidate for an anti-osteosarcoma drug in the near future, contingent upon its ability to induce apoptosis in osteosarcoma cell lines.
  3. Yong CY, Sudirman R, Chew KM
    Sains Malaysiana, 2015;44(12):1661-1669.
    A scalable tracking human model was proposed for recognizing human jogging and walking activities. The model aims to detect and track a particular subject by using wearable sensor. Data collected are in accelerometer readings in three axes and gyroscope readings in three axes. The development of proposed human model is based on the moderating effects on human movements. Two moderators were proposed as the moderating factors of human motion and they are angular velocity and elevation angle. Linear regression is used to investigate the relationship among inputs, moderators and outputs of the model. The result of this study showed that the angular velocity and elevation angle moderators are affecting the relation of research output. Acceleration in x-axis (Ax) and angular velocity in y-axis (Gy) are the two main components in directing
    a motion. Classification between jogging and walking motions was done by measuring the magnitude of angular velocity and elevation angle. Jogging motion was classified and identified with larger angular velocity and elevation angle. The two proposed hypotheses were supported and proved by research output. The result is expected to be beneficial and able to assist researcher in investigating human motions.
  4. Ong HK, Yong CY, Tan WS, Yeap SK, Omar AR, Razak MA, et al.
    Vaccines (Basel), 2019 08 19;7(3).
    PMID: 31430965 DOI: 10.3390/vaccines7030091
    Current seasonal influenza A virus (IAV) vaccines are strain-specific and require annual reconstitution to accommodate the viral mutations. Mismatches between the vaccines and circulating strains often lead to high morbidity. Hence, development of a universal influenza A vaccine targeting all IAV strains is urgently needed. In the present study, the protective efficacy and immune responses induced by the extracellular domain of Matrix 2 protein (M2e) displayed on the virus-like particles of Macrobrachium rosenbergii nodavirus (NvC-M2ex3) were investigated in BALB/c mice. NvC-M2ex3 was demonstrated to be highly immunogenic even in the absence of adjuvants. Higher anti-M2e antibody titers corresponded well with increased survival, reduced immunopathology, and morbidity of the infected BALB/c mice. The mice immunized with NvC-M2ex3 exhibited lower H1N1 and H3N2 virus replication in the respiratory tract and the vaccine activated the production of different antiviral cytokines when they were challenged with H1N1 and H3N2. Collectively, these results suggest that NvC-M2ex3 could be a potential universal influenza A vaccine.
  5. Chong LC, Ganesan H, Yong CY, Tan WS, Ho KL
    PLoS One, 2019;14(2):e0211740.
    PMID: 30707739 DOI: 10.1371/journal.pone.0211740
    Macrobrachium rosenbergii nodavirus (MrNV) is the causative agent of white tail disease (WTD) which seriously impedes the production of the giant freshwater prawn and has a major economic impact. MrNV contains two segmented RNA molecules, which encode the RNA dependent RNA polymerase (RdRp) and the capsid protein (MrNV-CP) containing 371 amino acid residues. MrNV-CP comprises of the Shell (S) and the Protruding (P) domains, ranging from amino acid residues 1-252 and 253-371, respectively. The P-domain assembles into dimeric protruding spikes, and it is believed to be involved in host cell attachment and internalization. In this study, the recombinant P-domain of MrNV-CP was successfully cloned and expressed in Escherichia coli, purified with an immobilized metal affinity chromatography (IMAC) and size exclusion chromatography (SEC) up to ~90% purity. Characterization of the purified recombinant P-domain with SEC revealed that it formed dimers, and dynamic light scattering (DLS) analysis demonstrated that the hydrodynamic diameter of the dimers was ~6 nm. Circular dichroism (CD) analysis showed that the P-domain contained 67.9% of beta-sheets, but without alpha-helical structures. This is in good agreement with the cryo-electron microscopic analysis of MrNV which demonstrated that the P-domain contains only beta-stranded structures. Our findings of this study provide essential information for the production of the P-domain of MrNV-CP that will aid future studies particularly studies that will shed light on anti-viral drug discovery and provide an understanding of virus-host interactions and the viral pathogenicity.
  6. Chong ZX, Yong CY, Ong AHK, Yeap SK, Ho WY
    Toxicology, 2023 Aug 15;495:153596.
    PMID: 37480978 DOI: 10.1016/j.tox.2023.153596
    Aryl hydrocarbon receptor (AHR) is a ligand-dependent receptor that belongs to the superfamily of basic helix-loop-helix (bHLH) transcription factors. The activation of the canonical AHR signaling pathway is known to induce the expression of cytochrome P450 enzymes, facilitating the detoxification metabolism in the human body. Additionally, AHR could interact with various signaling pathways such as epidermal growth factor receptor (EGFR), signal transducer and activator of transcription 3 (STAT3), hypoxia-inducible factor-1α (HIF-1α), nuclear factor ekappa B (NF-κβ), estrogen receptor (ER), and androgen receptor (AR) signaling pathways. Over the past 30 years, several studies have reported that various chemical, physical, or biological agents, such as tobacco, hydrocarbon compounds, industrial and agricultural chemical wastes, drugs, UV, viruses, and other toxins, could affect AHR expression or activity, promoting cancer development. Thus, it is valuable to overview how these factors regulate AHR-mediated carcinogenesis. Current findings have reported that many compounds could act as AHR ligands to drive the expressions of AHR-target genes, such as CYP1A1, CYP1B1, MMPs, and AXL, and other targets that exert a pro-proliferation or anti-apoptotic effect, like XIAP. Furthermore, some other physical and chemical agents, such as UV and 3-methylcholanthrene, could promote AHR signaling activities, increasing the signaling activities of a few oncogenic pathways, such as the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) and mitogen-activated protein kinase/extracellular signal-regulated kinase (MAPK/ERK) pathways. Understanding how various factors regulate AHR-mediated carcinogenesis processes helps clinicians and scientists plan personalized therapeutic strategies to improve anti-cancer treatment efficacy. As many studies that have reported the roles of AHR in regulating carcinogenesis are preclinical or observational clinical studies that did not explore the detailed mechanisms of how different chemical, physical, or biological agents promote AHR-mediated carcinogenesis processes, future studies should focus on conducting large-scale and functional studies to unravel the underlying mechanism of how AHR interacts with different factors in regulating carcinogenesis processes.
  7. Tang HC, Sieo CC, Abdullah N, Chong CW, Gan HM, Mohd Asrore MS, et al.
    J Anim Physiol Anim Nutr (Berl), 2020 Jan;104(1):116-125.
    PMID: 31556187 DOI: 10.1111/jpn.13208
    Inclusion of phytase in animal feedstuff is a common practice to enhance nutrients availability. However, little is known about the effects of phytase supplementation on the microbial ecology of the gastrointestinal tract. In this study, freeze-dried Mitsuokella jalaludinii phytase (MJ) was evaluated in a feeding trial with broilers fed a low available phosphorus (aP) diet. A total of 180 male broiler chicks (day-old Cobb) were assigned into three dietary treatments: Control fed with 0.4% (w/w) of available phosphorus (aP); Group T1 fed low aP [0.2% (w/w)] supplemented with MJ; and T2 fed low aP and deactivated MJ. The source of readily available P, dicalcium phosphate (DCP), was removed from low aP diet, whereby additional limestone was provided to replace the amount of Ca normally found in DCP. For each treatment, 4 replicate pens were used, where each pen consisted of 15 animals. The animals' energy intake and caecal bacterial community were monitored weekly for up to 3 weeks. The apparent metabolizable energy (AME) and apparent digestibility of dry matter (ADDM) of broilers fed with different diets were determined. In addition, the caecal microbial diversities of broilers were assessed using high-throughput next-generation sequencing targeting the V3-V4 region of bacterial 16S rRNA. The results showed that broilers fed with T1 diet have better feed conversion ratio (FCR) when compared to the Control (p 
  8. Yeap SK, Yong CY, Faruq U, Ong HK, Amin ZBM, Ho WY, et al.
    BMC Complement Med Ther, 2021 Mar 09;21(1):86.
    PMID: 33750373 DOI: 10.1186/s12906-021-03260-y
    BACKGROUND: Phyllanthus tenellus Roxb. has been traditionally used to treat inflammation and liver diseases and its medicinal property may be due to the presence of relatively high levels of hydrosable tannins. Recent report revealed that pressurized hot water extraction of P. tenellus significantly increased the concentration of hydrolysable tannins and its catabolites. Thus, this study was aimed to evaluate the in vivo toxicity and antioxidant capacity of pressurized hot water extraction of P. tenellus on healthy mice.

    METHODS: Pressurized hot water extraction P. tenellus was carried out and standardized to 7.9% hydrosable tannins. In vitro toxicity of the extract was tested on NIH 3 T3 cell by MTT assay. The cellular antioxidant level was quantified by measuring cellular level of glutathione. Oral sub-chronic toxicity (200, 1000 and 3000 mg/kg body weight) of P. tenellus extract were evaluated on healthy mice. Liver and kidney antioxidant level was quantified by measuring levels of Ferric Reducing Antioxidant Potential (FRAP), superoxide dismutase, glutathione.

    RESULTS: The P. tenellus extract did not induce cytotoxicity on murine NIH 3 T3 cells up to 200 μg/mL for 48 h. Besides, level of glutathione was higher in the extract treated NIH 3 T3 cells. P. tenellus extract did not cause mortality at all tested concentration. When treated with 1000 mg/kg of the extract, serum liver enzymes (ALP and ALT) and LDH were lower than normal control and mice treated with 200 mg/kg of extract. Moreover, SOD, FRAP and glutathione levels of liver of the mice treated with 200 and 1000 mg/kg of extract were higher than the normal control mice. On the other hand, when treated with 3000 mg/kg of extract, serum liver enzymes (ALP and ALT) and LDH were higher than normal mice without changing the liver SOD and glutathione level, which may contribute to the histological sign of ballooning hepatocyte.

    CONCLUSION: P. tenellus extract standardized with 7.9% hydrosable tannins and their catabolites increased the antioxidant levels while reducing the nitric oxide levels in both liver and kidney without causing any acute and sub-chronic toxicity in the mice.

  9. Abd Aziz N, Chue MC, Yong CY, Hassan Y, Awaisu A, Hassan J, et al.
    Int J Clin Pharm, 2011 Apr;33(2):150-4.
    PMID: 21744187 DOI: 10.1007/s11096-011-9480-7
    OBJECTIVE: To compare the efficacy of dexmedetomidine versus morphine as a sedative/analgesic among post-operative cardiac surgery patients.

    METHOD: A randomized controlled open-label study was performed at the cardiothoracic intensive care unit of Penang Hospital, Malaysia. A total of 28 patients who underwent cardiac surgeries were randomly assigned to receive either dexmedetomidine or morphine. Both groups were similar in terms of preoperative baseline characteristics. Efficacy measures included sedation scores and pain intensity and requirements for additional sedative/analgesic. Mean heart rate and arterial blood pressure were used as safety measures. Other measures were additional inotropes, extubation time and other concurrent medications.

    RESULTS: The mean dose of dexmedetomidine infused was 0.12 [SD 0.03] μg kg⁻¹ h⁻¹, while that of morphine was 13.2 [SD 5.84] μg kg⁻¹ h⁻¹. Dexmedetomidine group showed more benefits in sedation and pain levels, additional sedative/analgesic requirements, and extubation time. No significant differences between the two groups for the outcome measures, except heart rate, which was significantly lower in the dexmedetomidine group.

    CONCLUSION: This preliminary study suggests that dexmedetomidine was at least comparable to morphine in terms of efficacy and safety among cardiac surgery patients. Further studies with larger samples are recommended in order to determine the significant effects of the outcome measures.

  10. Sartini C, Lomivorotov V, Pieri M, Lopez-Delgado JC, Baiardo Redaelli M, Hajjar L, et al.
    J Cardiothorac Vasc Anesth, 2019 05;33(5):1430-1439.
    PMID: 30600204 DOI: 10.1053/j.jvca.2018.11.026
    The authors aimed to identify interventions documented by randomized controlled trials (RCTs) that reduce mortality in adult critically ill and perioperative patients, followed by a survey of clinicians' opinions and routine practices to understand the clinicians' response to such evidence. The authors performed a comprehensive literature review to identify all topics reported to reduce mortality in perioperative and critical care settings according to at least 2 RCTs or to a multicenter RCT or to a single-center RCT plus guidelines. The authors generated position statements that were voted on online by physicians worldwide for agreement, use, and willingness to include in international guidelines. From 262 RCT manuscripts reporting mortality differences in the perioperative and critically ill settings, the authors selected 27 drugs, techniques, and strategies (66 RCTs, most frequently published by the New England Journal of Medicine [13 papers], Lancet [7], and Journal of the American Medical Association [5]) with an agreement ≥67% from over 250 physicians (46 countries). Noninvasive ventilation was the intervention supported by the largest number of RCTs (n = 13). The concordance between agreement and use (a positive answer both to "do you agree" and "do you use") showed differences between Western and other countries and between anesthesiologists and intensive care unit physicians. The authors identified 27 clinical interventions with randomized evidence of survival benefit and strong clinician support in support of their potential life-saving properties in perioperative and critically ill patients with noninvasive ventilation having the highest level of support. However, clinician views appear affected by specialty and geographical location.
  11. Sartini C, Lomivorotov V, Pisano A, Riha H, Baiardo Redaelli M, Lopez-Delgado JC, et al.
    J Cardiothorac Vasc Anesth, 2019 Oct;33(10):2685-2694.
    PMID: 31064730 DOI: 10.1053/j.jvca.2019.03.022
    OBJECTIVE: Reducing mortality is a key target in critical care and perioperative medicine. The authors aimed to identify all nonsurgical interventions (drugs, techniques, strategies) shown by randomized trials to increase mortality in these clinical settings.

    DESIGN: A systematic review of the literature followed by a consensus-based voting process.

    SETTING: A web-based international consensus conference.

    PARTICIPANTS: Two hundred fifty-one physicians from 46 countries.

    INTERVENTIONS: The authors performed a systematic literature search and identified all randomized controlled trials (RCTs) showing a significant increase in unadjusted landmark mortality among surgical or critically ill patients. The authors reviewed such studies during a meeting by a core group of experts. Studies selected after such review advanced to web-based voting by clinicians in relation to agreement, clinical practice, and willingness to include each intervention in international guidelines.

    MEASUREMENTS AND MAIN RESULTS: The authors selected 12 RCTs dealing with 12 interventions increasing mortality: diaspirin-crosslinked hemoglobin (92% of agreement among web voters), overfeeding, nitric oxide synthase inhibitor in septic shock, human growth hormone, thyroxin in acute kidney injury, intravenous salbutamol in acute respiratory distress syndrome, plasma-derived protein C concentrate, aprotinin in high-risk cardiac surgery, cysteine prodrug, hypothermia in meningitis, methylprednisolone in traumatic brain injury, and albumin in traumatic brain injury (72% of agreement). Overall, a high consistency (ranging from 80% to 90%) between agreement and clinical practice was observed.

    CONCLUSION: The authors identified 12 clinical interventions showing increased mortality supported by randomized controlled trials with nonconflicting evidence, and wide agreement upon clinicians on a global scale.

  12. Tan FH, Kong JC, Ng JF, Alitheen NB, Wong CL, Yong CY, et al.
    J Appl Microbiol, 2021 Oct;131(4):2072-2080.
    PMID: 33629458 DOI: 10.1111/jam.15048
    AIMS: To display a short peptide (GSRSHHHHHH) at the C-terminal end of turnip yellow mosaic virus coat protein (TYMVc) and to study its assembly into virus-like particles (TYMVcHis6 VLPs).

    METHODS AND RESULTS: In this study, recombinant TYMVcHis6 expressed in Escherichia coli self-assembled into VLPs of approximately 30-32 nm. SDS-PAGE and Western blot analysis of protein fractions from the immobilized metal affinity chromatography (IMAC) showed that TYMVcHis6 VLPs interacted strongly with nickel ligands in IMAC column, suggesting that the fusion peptide is protruding out from the surface of VLPs. These VLPs are highly stable over a wide pH range from 3·0 to 11·0 at different temperatures. At pH 11·0, specifically, the VLPs remained intact up to 75°C. Additionally, the disassembly and reassembly of TYMVcHis6 VLPs were studied in vitro. Dynamic light scattering and transmission electron microscopy analysis revealed that TYMVcHis6 VLPs were dissociated by 7 mol l-1 urea and 2 mol l-1 guanidine hydrochloride (GdnHCl) without impairing their reassembly property.

    CONCLUSIONS: A 10-residue peptide was successfully displayed on the surface of TYMVcHis6 VLPs. This chimera demonstrated high stability under extreme thermal conditions with varying pH and was able to dissociate and reassociate into VLPs by chemical denaturants.

    SIGNIFICANCE AND IMPACT OF THE STUDY: This is the first C-terminally modified TYMVc produced in E.  coli. The C-terminal tail which is exposed on the surface can be exploited as a useful site to display multiple copies of functional ligands. The ability of the chimeric VLPs to self-assemble after undergo chemical denaturation indicates its potential role to serve as a nanocarrier for use in targeted drug delivery.

  13. Wong CL, Yong CY, Lee KW
    Methods Mol Biol, 2022;2412:75-93.
    PMID: 34918242 DOI: 10.1007/978-1-0716-1892-9_5
    Bacteriophages have been explored for their uses in vaccine development, due to the ease of propagation while displaying epitopes in high density. Bacteriophage T7 has been demonstrated to be useful in the production of potential vaccine candidates for various diseases, including influenza A, foot-and mouth disease (FMD), and cancers. In this chapter, we described the use of phage T7 to display potential foot-and-mouth disease virus (FMDV) epitope, from cloning to expression, purification, and immunization in a mouse model.
  14. Tan FH, Ng JF, Mohamed Alitheen NB, Muhamad A, Yong CY, Lee KW
    J Virol Methods, 2023 Sep;319:114771.
    PMID: 37437780 DOI: 10.1016/j.jviromet.2023.114771
    Virus-like particles (VLPs) is one of the most favourable subjects of study, especially in the field of nanobiotechnology and vaccine development because they possess good immunogenicity and self-adjuvant properties. Conventionally, VLPs can be tagged and purified using affinity chromatography or density gradient ultracentrifugation which is costly and time-consuming. Turnip yellow mosaic virus (TYMV) is a plant virus, where expression of the viral coat protein (TYMVc) in Escherichia coli (E. coli) has been shown to form VLP. In this study, we report a non-chromatographic method for VLP purification using C-terminally His-tagged TYMVc (TYMVcHis6) as a protein model. Firstly, the TYMVcHis6 was cloned and expressed in E. coli. Upon clarification of cell lysate, nickel (II) chloride [NiCl2; 15 µM or equivalent to 0.0000194% (w/v)] was added to precipitate TYMVcHis6. Following centrifugation, the pellet was resuspended in buffer containing 1 mM EDTA to chelate Ni2+, which is then removed via dialysis. A total of 50% of TYMVcHis6 was successfully recovered with purity above 0.90. Later, the purified TYMVcHis6 was analysed with sucrose density ultracentrifugation, dynamic light scattering (DLS), and transmission electron microscopy (TEM) to confirm VLP formation, which is comparable to TYMVcHis6 purified using the standard immobilized metal affinity chromatography (IMAC) column. As the current method omitted the need for IMAC column and beads while significantly reducing the time needed for column washing, nickel affinity precipitation represents a novel method for the purification of VLPs displaying poly-histidine tags (His-tags).
  15. Ma PY, Tan JE, Hee EW, Yong DWX, Heng YS, Low WX, et al.
    Cells, 2021 02 06;10(2).
    PMID: 33562108 DOI: 10.3390/cells10020345
    In the 21st century, enteric fever is still causing a significant number of mortalities, especially in high-risk regions of the world. Genetic studies involving the genome and transcriptome have revealed a broad set of candidate genetic polymorphisms associated with susceptibility to and the severity of enteric fever. This review attempted to explain and discuss the past and the most recent findings on human genetic variants affecting the progression of Salmonella typhoidal species infection, particularly toll-like receptor (TLR) 4, TLR5, interleukin (IL-) 4, natural resistance-associated macrophage protein 1 (NRAMP1), VAC14, PARK2/PACRG, cystic fibrosis transmembrane conductance regulator (CFTR), major-histocompatibility-complex (MHC) class II and class III. These polymorphisms on disease susceptibility or progression in patients could be related to multiple mechanisms in eliminating both intracellular and extracellular Salmonella typhoidal species. Here, we also highlighted the limitations in the studies reported, which led to inconclusive results in association studies. Nevertheless, the knowledge obtained through this review may shed some light on the development of risk prediction tools, novel therapies as well as strategies towards developing a personalised typhoid vaccine.
  16. Abd Razak N, Yeap SK, Alitheen NB, Ho WY, Yong CY, Tan SW, et al.
    Integr Cancer Ther, 2020 8 25;19:1534735420935625.
    PMID: 32830560 DOI: 10.1177/1534735420935625
    Eupatorin is a polymethoxy flavone extracted from Orthosiphon stamineus and was reported to exhibit cytotoxic effects on several cancer cell lines. However, its effect as an anti-breast cancer agent in vivo has yet to be determined. This study aims to elucidate the potential of eupatorin as an anti-breast cancer agent in vivo using 4T1 challenged BALB/c mice model. In this article, BALB/c mice (20-22 g) challenged with 4T1 cells were treated with 5 mg/kg or 20 mg/kg eupatorin, while the untreated and healthy mice were fed with olive oil (vehicle) via oral gavage. After 28 days of experiment, the mice were sacrificed and blood was collected for serum cytokine assay, while tumors were harvested to extract RNA and protein for gene expression assay and hematoxylin-eosin staining. Organs such as spleen and lung were harvested for immune suppression and clonogenic assay, respectively. Eupatorin (20 mg/kg) was effective in delaying the tumor development and reducing metastasis to the lung compared with the untreated mice. Eupatorin (20 mg/kg) also enhanced the immunity as the population of NK1.1+ and CD8+ in the splenocytes and the serum interferon-γ were increased. Concurrently, eupatorin treatment also has downregulated the expression of pro-inflammatory and metastatic related genes (IL-1β. MMP9, TNF-α, and NF-κB). Thus, this study demonstrated that eupatorin at the highest dosage of 20 mg/kg body weight was effective in delaying the 4T1-induced breast tumor growth in the animal model.
  17. Zangrillo A, Lomivorotov VV, Pasyuga VV, Belletti A, Gazivoda G, Monaco F, et al.
    PMID: 35168907 DOI: 10.1053/j.jvca.2022.01.001
    OBJECTIVE: To investigate the effect of volatile anesthetics on the rates of postoperative myocardial infarction (MI) and cardiac death after coronary artery bypass graft (CABG).

    DESIGN: A post hoc analysis of a randomized trial.

    SETTING: Cardiac surgical operating rooms.

    PARTICIPANTS: Patients undergoing elective, isolated CABG.

    INTERVENTIONS: Patients were randomized to receive a volatile anesthetic (desflurane, isoflurane, or sevoflurane) or total intravenous anesthesia (TIVA). The primary outcome was hemodynamically relevant MI (MI requiring high-dose inotropic support or prolonged intensive care unit stay) occurring within 48 hours from surgery. The secondary outcome was 1-year death due to cardiac causes.

    MEASUREMENTS AND MAIN RESULTS: A total of 5,400 patients were enrolled between April 2014 and September 2017 (2,709 patients randomized to the volatile anesthetics group and 2,691 to TIVA). The mean age was 62 ± 8.4 years, and the median baseline ejection fraction was 57% (50-67), without differences between the 2 groups. Patients in the volatile group had a lower incidence of MI with hemodynamic complications both in the per-protocol (14 of 2,530 [0.6%] v 27 of 2,501 [1.1%] in the TIVA group; p = 0.038) and as-treated analyses (16 of 2,708 [0.6%] v 29 of 2,617 [1.1%] in the TIVA group; p = 0.039), but not in the intention-to-treat analysis (17 of 2,663 [0.6%] v 28 of 2,667 [1.0%] in the TIVA group; p = 0.10). Overall, deaths due to cardiac causes were lower in the volatile group (23 of 2,685 [0.9%] v 40 of 2,668 [1.5%] than in the TIVA group; p = 0.03).

    CONCLUSIONS: An anesthetic regimen, including volatile agents, may be associated with a lower rate of postoperative MI with hemodynamic complication in patients undergoing CABG. Furthermore, it may reduce long-term cardiac mortality.

  18. Yong CY, Liew WPP, Ong HK, Poh CL
    Biotechnol Prog, 2022 Nov;38(6):e3292.
    PMID: 35932092 DOI: 10.1002/btpr.3292
    Severe acute respiratory syndrome coronavirus (SARS-CoV), Middle East respiratory syndrome coronavirus (MERS-CoV), and the current severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are the most impactful coronaviruses in human history, especially the latter, which brings revolutionary changes to human vaccinology. Due to its high infectivity, the virus spreads rapidly throughout the world and was declared a pandemic in March 2020. A vaccine would normally take more than 10 years to be developed. As such, there is no vaccine available for SARS-CoV and MERS-CoV. Currently, 10 vaccines have been approved for emergency use by World Health Organization (WHO) against SARS-CoV-2. Virus-like particle (VLP)s are nanoparticles resembling the native virus but devoid of the viral genome. Due to their self-adjuvanting properties, VLPs have been explored extensively for vaccine development. However, none of the approved vaccines against SARS-CoV-2 was based on VLP and only 4% of the vaccine candidates in clinical trials were based on VLPs. In the current review, we focused on discussing the major advances in the development of VLP-based vaccine candidates against the SARS-CoV, MERS-CoV, and SARS-CoV-2, including those in clinical and pre-clinical studies, to give a comprehensive overview of the VLP-based vaccines against the coronaviruses.
  19. Shehabi Y, Chan L, Kadiman S, Alias A, Ismail WN, Tan MA, et al.
    Intensive Care Med, 2013 May;39(5):910-8.
    PMID: 23344834 DOI: 10.1007/s00134-013-2830-2
    PURPOSE: To ascertain the relationship among early (first 48 h) deep sedation, time to extubation, delirium and long-term mortality.

    METHODS: We conducted a multicentre prospective longitudinal cohort study in 11 Malaysian hospitals including medical/surgical patients (n = 259) who were sedated and ventilated ≥24 h. Patients were followed from ICU admission up to 28 days in ICU with 4-hourly sedation and daily delirium assessments and 180-day mortality. Deep sedation was defined as Richmond Agitation Sedation Score (RASS) ≤-3.

    RESULTS: The cohort had a mean (SD) age of 53.1 (15.9) years and APACHE II score of 21.3 (8.2) with hospital and 180-day mortality of 82 (31.7%) and 110/237 (46.4%). Patients were followed for 2,657 ICU days and underwent 13,836 RASS assessments. Midazolam prescription was predominant compared to propofol, given to 241 (93%) versus 72 (28%) patients (P < 0.0001) for 966 (39.6%) versus 183 (7.5%) study days respectively. Deep sedation occurred in (182/257) 71% patients at first assessment and in 159 (61%) patients and 1,658 (59%) of all RASS assessments at 48 h. Multivariable Cox proportional hazard regression analysis adjusting for a priori assigned covariates including sedative agents, diagnosis, age, APACHE II score, operative, elective, vasopressors and dialysis showed that early deep sedation was independently associated with longer time to extubation [hazard ratio (HR) 0.93, 95% confidence interval (CI) 0.89-0.97, P = 0.003], hospital death (HR 1.11, 95% CI 1.05-1.18, P < 0.001) and 180-day mortality (HR 1.09, 95% CI 1.04-1.15, P = 0.002), but not time to delirium (HR 0.98, P = 0.23). Delirium occurred in 114 (44%) of patients.

    CONCLUSION: Irrespective of sedative choice, early deep sedation was independently associated with delayed extubation and higher mortality, and thus was a potentially modifiable risk in interventional trials.

  20. Yong CY, Yeap SK, Ho KL, Omar AR, Tan WS
    Int J Nanomedicine, 2015;10:2751-63.
    PMID: 25897220 DOI: 10.2147/IJN.S77405
    Influenza A virus poses a major threat to human health, causing outbreaks from time to time. Currently available vaccines employ inactivated viruses of different strains to provide protection against influenza virus infection. However, high mutation rates of influenza virus hemagglutinin (H) and neuraminidase (N) glycoproteins give rise to vaccine escape mutants. Thus, an effective vaccine providing protection against all strains of influenza virus would be a valuable asset. The ectodomain of matrix 2 protein (M2e) was found to be highly conserved despite mutations of the H and N glycoproteins. Hence, one to five copies of M2e were fused to the carboxyl-terminal end of the recombinant nodavirus capsid protein derived from Macrobrachium rosenbergii. The chimeric proteins harboring up to five copies of M2e formed nanosized virus-like particles approximately 30 nm in diameter, which could be purified easily by immobilized metal affinity chromatography. BALB/c mice immunized subcutaneously with these chimeric proteins developed antibodies specifically against M2e, and the titer was proportional to the copy numbers of M2e displayed on the nodavirus capsid nanoparticles. The fusion proteins also induced a type 1 T helper immune response. Collectively, M2e displayed on the nodavirus capsid nanoparticles could provide an alternative solution to a possible influenza pandemic in the future.
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