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Lithium restores nuclear REST and Mitigates oxidative stress in down syndrome iPSC-Derived neurons
No full textDown syndrome (DS), caused by trisomy 21, is characterized by intellectual disability and accelerated aging, with chronic oxidative stress contributing to neurological deficits. REST (Repressor Element-1 Silencing Transcription factor) is a crucial regulator of neuronal gene expression implicated in DS neuropathology. This study investigates the neuroprotective potential of lithium, a mood stabilizer with known cognitive-enhancing effects, in restoring levels of REST. Using three pairs of human disomic and trisomic DS induced pluripotent stem cell (iPSC) isogenic lines, we differentiated neurons and treated them with lithium. Nuclear REST expression and reactive oxygen species (ROS) levels were quantified. Results showed the significantly lower nuclear REST expression in DS neurons was restored after 24 hours of 10 mM lithium carbonate treatment. Notably, lithium treatment selectively reduced ROS levels in DS neurons to near-baseline levels. When challenged with hydrogen peroxide, DS neurons exhibited increased vulnerability to oxidative stress. The lithium treatment also significantly reduced ROS levels in the stressed control neurons. These findings reveal a positive association between lithium treatment, REST restoration, and oxidative stress reduction, suggesting that repurposing lithium could contribute to developing therapeutic strategies for DS neuropathologies. This study provides novel insights into DS molecular mechanisms and highlights the potential of lithium as a targeted intervention for improving neuronal functionin DS
Pathogenicity, enzymatic assays, and differential metabolomics to assess the virulence of fungal pathogens responsible for complex circular leaf spot (CCLS) disease of rubber trees in Malaysia
No full textThe rubber tree (Hevea brasiliensis Muell. Arg.) is susceptible to an array of foliar diseases. A severe epidemic characterised by circular leaf spot symptoms on rubber leaves has recently infested rubber plantations in various rubber-producing countries, resulting in secondary leaf fall and a considerable production drop. This new disease is known as complex circular leaf spot disease (CCLS). The purpose of this study was to identify the causative pathogen(s) of CCLS disease using an in vivo pathogenicity test. Other than that, assessment of metabolites and leaf-degrading enzymes excreted by the causal pathogen(s) were carried out. The pathogenicity test was conducted using three-month-old rubber seedlings of clone PB 350. Microbe metabolite extraction was carried out on the potential isolated fungal pathogens, and the samples were subjected to gas chromatography-mass spectrometry (GC-MS) analysis. Four enzyme assays were also conducted: polygalacturonase (E.C. 3.2.1.15), pectin lyase (E.C. 4.2.2.10), endoglucanase (E.C. 3.2.1.4), and β-glucosidase (E.C. 3.2.1.21). Results from the pathogenicity test demonstrated that both fungi were able to initiate CCLS infections. Leaf inoculated with a spore suspension of Colletotrichum siamense produced the biggest mean lesion length, and the lesion resembled the symptoms of the disease in rubber plantations. Based on observations through a scanning electron microscope, the spores of C. siamense dominate the surface of the leaf lesions. Results from GC-MS analysis showed that microbial volatile organic compounds emitted by C. siamense have higher concentrations than those emitted by Pestalotiopsis jesteri. A total of 24 metabolites were detected in C. siamense and six metabolites in P. jesteri. In addition, C. siamense were also recorded to produce higher concentration of leaf degrading enzymes compared to P. jesteri in the enzyme assays conducted
UPM dan Al-Ikhsan perkasa pelajar sekolah dalam bidang perniagaan sukan
Get PDFSERDANG, 26 Februari – Sekolah Perniagaan dan Ekonomi (SPE), Universiti Putra Malaysia (UPM) dengan kerjasama Al-Ikhsan Sports telah melancarkan program perantis bagi pelajar sekolah menengah, bertujuan memperkasa kemahiran dalam bidang perniagaan, pemasaran, dan pengurusan bakat sukan
Gut microbiota and functional metabolic predictions in white feces disease-infected Pacific white shrimp, Penaeus vannamei, from Indonesian farms
No full textThe etiological agent of white feces disease (WFD) infecting Pacific white shrimp Penaeus vannamei in Indonesia farms remains obscure. The present study aimed to identify possible causative agents of WFD infection in Pacific white shrimps cultured in Indonesian farms. WFD-infected and healthy samples (shrimp gut and rearing water) were collected from 8 commercial shrimp farms in East Java, Indonesia followed by bacterial community profiling using HiSeq sequencing of 16S rRNA gene amplicons. The results showed that the microbiota composition in the guts of WFD-infected shrimps was significantly different (p < 0.05) from the guts of healthy shrimps in term of genus and bacterial species. The intestinal bacterial communities of WFS-infected shrimps were overrepresented by Vibrio coralliilyticus, whereas Paracoccus was underrepresented. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States functional predictions indicated that relative abundances of 12 genes associated with the pathogenicity of bacteria including amino acid metabolisms, carbohydrate metabolisms, glycan biosynthesis, and xenobiotic biodegradation and metabolism were significantly (p < 0.05) higher in the gut microbiota of WFD-infected shrimps. These findings provide insights into the microbiome domination and their metabolic activities in the digestive tract of WFD-infected shrimps and suggest that V. coralliilyticus is a possible causative agent of WFD in cultured Indonesia Pacific white shrimp. © 2025 Elsevier Lt
Inisiatif Program Towards Zero Food Waste UPMKB berjaya kurangkan lebih 500kg sisa makanan
No full textBINTULU, 25 Mac – Universiti Putra Malaysia Kampus Bintulu (UPMKB) dengan kerjasama Lembaga Kemajuan Bintulu (BDA) berjaya mengurangkan lebih 500 kilogram sisa makanan di Bazaar Ramadan BDA, Esplanade Bintulu menerusi inisiatif 'Towards Zero Food Waste in Bintulu'
Optimising bismuth magnesium niobate pyrochlores as potential ceramic dielectrics: Reaction progression, phase equilibria and impedance properties
No full textThe phase-pure Bi2O3-MgO-M2O5 (BMN) cubic pyrochlores formed across a broad compositional range, with
bismuth content varying from 41.88 to 44.50 mol %. The quadrilateral subsolidus region is defined by two
substitution mechanisms: (i) Mg2+ substitution by Nb5+, balanced by oxygen stoichiometry variations and (ii)
one-to-one Bi3+ replacement by Nb5+, with charge compensation by O2− . This yields a general formula of
Bi3.36+xMg1.92-yNb2.72-x + yO13.76-x+(3/2)y, involving two variables with the corresponding subsolidus solution
limits of 0.10 ≤ x ≤ 0.20 and 0.00 ≤ y ≤ 0.16, respectively. Notably, these BMN pyrochlores exhibit high
dielectric constants, ε′ in the range of 167–204 at 30 ◦C, 1 MHz and low dielectric losses, tan δ in the order of
10− 4 - 10− 3
. The elevated dielectric constant is likely due to the enhanced polarisability of Nb2O5 within the
crucial BO6 octahedra of the pyrochlore structure. Furthermore, these pyrochlores display negative temperature
coefficients of permittivity, TCε’ ranging from − 528 to − 742 ppm/◦C at 30–300 ◦C and 1 MHz. These thermally
stable and highly insulating BMN pyrochlores with high activation energies, Ea >1.0 eV, are promising candidate
for potential application in ceramic capacitors
Influence of Sn4+ substitution on the Ba(Zn1/3Nb2/3)1-xSnxO3 (0 ≤ x ≤ 1) perovskites: Doping mechanism, structural and dielectric properties
No full textHerein, we investigated the chemically modified Ba(Zn1/3Nb2/3)1-xSnxO3 (0 ≤ x ≤ 1) perovskites synthesised by solid-state reaction from the perspectives of doping mechanisms, microstructural and dielectric properties. The Rietveld refinement analysis affirmed that these perovskites possess a cubic structure with a space group of Pm 3‾ m. The polyhedral grains ranged from 225 to 88 nm, exhibiting a gradual decrease due to increasing Sn4+ concentration. Meanwhile, the chemical stoichiometry and oxidation states of the constituent elements were validated by the elemental analyses using ICP-OES, EDS and XPS, respectively. The FT-IR spectra displayed a slight blue shift related to the NbO6 octahedra; whilst, the Raman spectroscopy confirmed a vibration of SnO6 octahedra. A strong correlation was observed between the dielectric properties and various factors including pellet density, polarisation per molar volume, packing fraction and bond valence sum. Notably, the impedance study revealed the behaviours of negative temperature coefficient of resistance (NTCR) and non-Debye relaxation in these perovskites. The AC conductivity was also found to follow a conduction barrier hopping (CBH) model over the temperature range of 500–700 °C, suggesting that the charge carrier could be attributed to double ionised oxygen vacancies (Vo••) in the host structure