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Enhanced modelling and experimental validation of ultra-low pressure reverse osmosis membrane system for treatment of synthetic brackish water

Norizam SS, Hussain MA, Junaidi MUM

Water Sci Technol, 2021 Nov;84(10-11):3372-3387.
PMID: 34850734 DOI: 10.2166/wst.2021.442

Water purification from brackish water sources has been acknowledged as one of the most promising ways to produce drinkable water in water-scarce areas. In this study, an ultra-low pressure reverse osmosis (ULPRO) membrane was numerically and experimentally investigated to produce drinking water by the removal of sodium chloride salt which provides further validation of the model from a practical perspective. An enhanced predictive model based on the Donnan-Steric Pore Model with dielectric exclusion (DSPM-DE) incorporating the osmotic effects was formulated in process simulation. The feed pressure and concentration were optimized as input variables and interaction between them was observed, while salt rejection and water recovery rate were taken as response attributes. The results obtained on the ULPRO membrane showed that the performance depends on the charge, steric, and dielectric effects. Furthermore, the enhanced model was validated with the experimental data attained from a laboratory-scale filtration system with good accuracy in the salt rejection and water recovery results. Comparing the enhanced DSPM-DE with the existing solution diffusion model reveals that the enhanced model predicts the membrane performance better and thereby qualifies itself as a reliable model for desalination of brackish water using ULPRO membrane.
A comparison of real-world effectiveness of vortioxetine along the treatment algorithm for major depressive disorder

Bose R, Hamdani SU, Minhas FA, Herr KJ

Curr Med Res Opin, 2022 Jan 20.
PMID: 35049384 DOI: 10.1080/03007995.2022.2031146

OBJECTIVE: To evaluate the effectiveness of vortioxetine in major depressive disorder (MDD) when used as a first-line versus second-line treatment or later.
METHODS: This was a post-hoc analysis of three 3-month non-interventional, prospective studies of vortioxetine in MDD - REVIDA (Malaysia, Philippines, Singapore, Thailand), PREVIDA (Pakistan) and TREVIDA (Taiwan). Improvements in depressive symptoms (PHQ-9, CGI-S), cognitive function (PDQ-D) and work productivity (WPAI) were compared between studies, and in a pooled analysis of patients using vortioxetine as first line versus second-line treatment or later. Safety was compared between studies.
RESULTS: Overall, 798 patients were analyzed (PREVIDA =425, REVIDA =130, TREVIDA =243). Most patients in PREVIDA (60.5%)/REVIDA (57.4%) used vortioxetine as first-line treatment versus TREVIDA (21.8%). Generally, greater improvements from baseline were observed across outcome measures in PREVIDA/REVIDA versus TREVIDA (Month 3, p
Fulltext Impact of COVID-19 pandemic on multidrug resistant gram positive and gram negative pathogens: A systematic review

Abubakar U, Al-Anazi M, Alanazi Z, Rodríguez-Baño J

J Infect Public Health, 2023 Mar;16(3):320-331.
PMID: 36657243 DOI: 10.1016/j.jiph.2022.12.022

BACKGROUND: There is paucity of data describing the impact of COVID-19 pandemic on antimicrobial resistance. This review evaluated the changes in the rate of multidrug resistant gram negative and gram positive bacteria during the COVID-19 pandemic.
METHODS: A search was conducted in PubMed, Science Direct, and Google Scholar databases to identify eligible studies. Studies that reported the impact of COVID-19 pandemic on carbapenem-resistant Acinetobacter baumannii (CRAB), carbapenem-resistant Enterobacteriaceae (CRE), extended-spectrum beta-lactamase inhibitor (ESBL)-producing Enterobacteriaceae, vancomycin-resistant enterococci (VRE), methicillin-resistant Staphylococcus aureus (MRSA) and carbapenem-resistant Pseudomonas aeruginosa (CPE) were selected. Studies published in English language from the start of COVID-19 pandemic to July 2022 were considered for inclusion.
RESULTS: Thirty eligible studies were selected and most of them were from Italy (n = 8), Turkey (n = 3) and Brazil (n = 3). The results indicated changes in the rate of multidrug resistant bacteria, and the changes varied between the studies. Most studies (54.5%) reported increase in MRSA infection/colonization during the pandemic, and the increase ranged from 4.6 to 170.6%. Five studies (55.6%) reported a 6.8-65.1% increase in VRE infection/colonization during the pandemic. A 2.4-58.2% decrease in ESBL E. coli and a 1.8-13.3% reduction in ESBL Klebsiella pneumoniae was observed during the pandemic. For CRAB, most studies (58.3%) reported 1.5-621.6% increase in infection/colonization during the pandemic. Overall, studies showed increase in the rate of CRE infection/colonization during the pandemic. There was a reduction in carbapenem-resistant E. coli during COVID-19 pandemic, and an increase in carbapenem-resistant K. pneumoniae. Most studies (55.6%) showed 10.4 - 40.9% reduction in the rate of CRPA infection during the pandemic.
CONCLUSION: There is an increase in the rate of multidrug resistant gram positive and gram negative bacteria during the COVID-19 pandemic. However, the rate of ESBL-producing Enterobacteriaceae and CRPA has decrease during the pandemic. Both infection prevention and control strategies and antimicrobial stewardship should be strengthen to address the increasing rate of multidrug resistant gram positive and gram negative bacteria.
Alpha terpineol directs bone marrow mesenchymal stem cells toward neuronal lineage through regulation of wnt signaling pathway

Ishaque A, Salim A, Simjee SU, Khan I, Adli DSH

Cell Biochem Funct, 2023 Mar;41(2):223-233.
PMID: 36651266 DOI: 10.1002/cbf.3775

Central nervous system anomalies give rise to neuropathological consequences with immense damage to the neuronal tissues. Cell based therapeutics have the potential to manage several neuropathologies whereby the differentiated cells are explored for neuronal regeneration. The current study analyzes the effect of a bioactive compound, alpha terpineol (AT) on the differentiation of rat bone marrow derived mesenchymal stem cells (BM-MSCs) toward neuronal lineage, and explores regulation of differentiation process through the study of Wnt pathway mediators. BM-MSCs were cultured and characterized based on their surface markers and tri-lineage differentiation. Safe dose of AT as optimized by 3-(4,5-Dimethylthiazol-2-yl)-2,5-Diphenyltetrazolium bromide assay, was used for the treatment of MSCs. Treated cells were analyzed for the neuronal, astroglial and germ layer transition markers at the gene and protein levels, by quantitative polymerase chain reaction and immunocytochemistry, respectively. Temporal expression of Wnt pathway genes was assessed during the course of neuronal differentiation. AT treated group showed significant upregulation of neuron specific (NSE, MAP2, Tau, Nestin, and NefL) and astroglial (GFAP) genes with positive expression of late neuronal markers. Germ layer transition analysis showed the overexpression of ectodermal markers (NCAM, Nestin, and Pax6), whereas endodermal (AFP, MixL1, and Sox17), and mesodermal (Mesp1 and T Brachyury) markers were also found to be upregulated. Wnt signaling pathway was activated during the initial phase (30 min) of differentiation, which later was downregulated at 1, 3, and 5 h. AT efficiently induces neuronal differentiation of BM-MSCs by regulating Wnt signaling. Overexpression of both early and late neuronal markers indicate their neuro-progenitor state and thus can be utilized as a promising approach in cellular therapeutics to treat various neurodegenerative ailments. In addition, exploration of the molecular pathways may be helpful to understand the mechanism of cell-based neuronal regeneration.
Fulltext Ensemble learning for multi-class COVID-19 detection from big data

Kaleem S, Sohail A, Tariq MU, Babar M, Qureshi B

PLoS One, 2023;18(10):e0292587.
PMID: 37819992 DOI: 10.1371/journal.pone.0292587

Coronavirus disease (COVID-19), which has caused a global pandemic, continues to have severe effects on human lives worldwide. Characterized by symptoms similar to pneumonia, its rapid spread requires innovative strategies for its early detection and management. In response to this crisis, data science and machine learning (ML) offer crucial solutions to complex problems, including those posed by COVID-19. One cost-effective approach to detect the disease is the use of chest X-rays, which is a common initial testing method. Although existing techniques are useful for detecting COVID-19 using X-rays, there is a need for further improvement in efficiency, particularly in terms of training and execution time. This article introduces an advanced architecture that leverages an ensemble learning technique for COVID-19 detection from chest X-ray images. Using a parallel and distributed framework, the proposed model integrates ensemble learning with big data analytics to facilitate parallel processing. This approach aims to enhance both execution and training times, ensuring a more effective detection process. The model's efficacy was validated through a comprehensive analysis of predicted and actual values, and its performance was meticulously evaluated for accuracy, precision, recall, and F-measure, and compared to state-of-the-art models. The work presented here not only contributes to the ongoing fight against COVID-19 but also showcases the wider applicability and potential of ensemble learning techniques in healthcare.
Fulltext Identification of novel human USP2 inhibitor and its putative role in treatment of COVID-19 by inhibiting SARS-CoV-2 papain-like (PLpro) protease

Mirza MU, Ahmad S, Abdullah I, Froeyen M

Comput Biol Chem, 2020 Dec;89:107376.
PMID: 32979815 DOI: 10.1016/j.compbiolchem.2020.107376

Human ubiquitin carboxyl-terminal hydrolase-2 (USP2) inhibitors, such as thiopurine analogs, have been reported to inhibit SARS-CoV papain-like proteases (PLpro). The PLpro have significant functional implications in the innate immune response during SARS-CoV-2 infection and considered an important antiviral target. Both proteases share strikingly similar USP fold with right-handed thumb-palm-fingers structural scaffold and conserved catalytic triad Cys-His-Asp/Asn. In this urgency situation of COVID-19 outbreak, there is a lack of in-vitro facilities readily available to test SARS-CoV-2 inhibitors in whole-cell assays. Therefore, we adopted an alternate route to identify potential USP2 inhibitor through integrated in-silico efforts. After an extensive virtual screening protocol, the best compounds were selected and tested. The compound Z93 showed significant IC50 value against Jurkat (9.67 μM) and MOTL-4 cells (11.8 μM). The binding mode of Z93 was extensively analyzed through molecular docking, followed by MD simulations, and molecular interactions were compared with SARS-CoV-2. The relative binding poses of Z93 fitted well in the binding site of both proteases and showed consensus π-π stacking and H-bond interactions with histidine and aspartate/asparagine residues of the catalytic triad. These results led us to speculate that compound Z93 might be the first potential chemical lead against SARS-CoV-2 PLpro, which warrants in-vitro evaluations.
Fulltext The prevalence of dental agenesis among children with cleft lip and palate patients in Lahore, Pakistan

Zaheer N, Shabaz M, Zaheer U, Wyne AH

Pak J Med Sci, 2024;40(3Part-II):421-426.
PMID: 38356796 DOI: 10.12669/pjms.40.3.7997

OBJECTIVE: This retrospective, cross-sectional analytical study investigated the incidence of tooth agenesis in cleft lip and palate (CLP) patients. Cone Beam Computed Tomography (CBCT) radiographs of the CLP children were examined for congenitally missing teeth.
METHOD: This study was conducted at three radiology centers in Lahore, namely, the Pakistan Jinnah MRI and Body Scan Centre, the University of Lahore Radiology Centres, and Fatima Memorial Hospital, from September 2021 to August 2022. The CLP patients were divided into four groups based on the location of the cleft: Cleft Lip and Palate Right (CLPR), Cleft Lip and Palate Left (CLPL), Bilateral Cleft (CLPB), and Midline Cleft (CLPM), inside and outside the cleft region. Two-way ANOVA was employed to compare the means of agenesis. Tukey's test was utilized to ascertain where the difference lies. The significance level was set at p ≤ 0.05.
RESULTS: Moreover, a significant number of missing teeth were found inside the cleft. This study observed the CLPL (42.3%) and CLPR (13.6%) types more in number. Maxillary first premolars were found more missing outside the cleft region in CLPL and CLPB types. Although CLPB and CLPM types revealed a pattern of missing teeth, only a few cases were found in this study. Moreover, mean tooth agenesis was highest (4.5 SD.71) in the CLPM group, followed up by CLPB (2.75 SD 2.49), CLPR (1.23 SD 1.27), and CLPL Group (1.15 SD 1.12).
CONCLUSIONS: Unilateral cleft lip and palate patients reported significant agenesis patttern compared to bilateral and median cleft cases.
Vitamin B12 Deficiency, a Rare Cause of Isolated Thrombocytopenia in Adults

Khan MAN, Ghani U, Surani S, Aftab A

Cureus, 2023 Aug;15(8):e44162.
PMID: 37753039 DOI: 10.7759/cureus.44162

Isolated thrombocytopenia in adults is a common clinical problem, often caused by various hematological disorders. However, vitamin B12 deficiency as a rare cause of isolated thrombocytopenia has been rarely reported in the medical literature. This case report aims to highlight the diagnostic challenges associated with atypical presentations of thrombocytopenia and emphasizes the importance of considering nutritional deficiencies, such as vitamin B12 deficiency, in the diagnostic workup. We report the case of a 38-year-old male who presented with generalized weakness, fatigue, and a history of bruises without trauma. Physical examination and laboratory investigations revealed thrombocytopenia (42 K/µL) with normal red blood cell morphology and no apparent abnormalities in other hematological parameters. Serum vitamin B12 levels were significantly diminished (128 pg/ml). The patient was treated with subcutaneous mecobalamin 1000 mcg supplementation, resulting in improvements in serum vitamin B12 levels (772 pg/ml) and platelet count (154 × 109/L) values. This case highlights the importance of considering vitamin B12 deficiency as a potential cause of isolated thrombocytopenia in adults. The lack of hypersegmented neutrophils and characteristic signs of macrocytic anemia in the context of vitamin B12 deficiency emphasizes the necessity for a thorough investigation to rule out other possible causes. Hematological problems associated with thrombocytopenia caused by vitamin B12 deficiency can be treated early to resolve them and avoid complications.
Fulltext Harnessing the power of AI: Advanced deep learning models optimization for accurate SARS-CoV-2 forecasting

Tariq MU, Ismail SB, Babar M, Ahmad A

PLoS One, 2023;18(7):e0287755.
PMID: 37471397 DOI: 10.1371/journal.pone.0287755

The pandemic has significantly affected many countries including the USA, UK, Asia, the Middle East and Africa region, and many other countries. Similarly, it has substantially affected Malaysia, making it crucial to develop efficient and precise forecasting tools for guiding public health policies and approaches. Our study is based on advanced deep-learning models to predict the SARS-CoV-2 cases. We evaluate the performance of Long Short-Term Memory (LSTM), Bi-directional LSTM, Convolutional Neural Networks (CNN), CNN-LSTM, Multilayer Perceptron, Gated Recurrent Unit (GRU), and Recurrent Neural Networks (RNN). We trained these models and assessed them using a detailed dataset of confirmed cases, demographic data, and pertinent socio-economic factors. Our research aims to determine the most reliable and accurate model for forecasting SARS-CoV-2 cases in the region. We were able to test and optimize deep learning models to predict cases, with each model displaying diverse levels of accuracy and precision. A comprehensive evaluation of the models' performance discloses the most appropriate architecture for Malaysia's specific situation. This study supports ongoing efforts to combat the pandemic by offering valuable insights into the application of sophisticated deep-learning models for precise and timely SARS-CoV-2 case predictions. The findings hold considerable implications for public health decision-making, empowering authorities to create targeted and data-driven interventions to limit the virus's spread and minimize its effects on Malaysia's population.
Fulltext I Have Had Enough: When and How Customer Mistreatment Leads to Coworker Undermining

Huilian Z, Waqas M, Yahya F, Ahmad Qadri U, Zahid F

Front Psychol, 2022;13:629901.
PMID: 35615183 DOI: 10.3389/fpsyg.2022.629901

Service workers are more prone to experience customer mistreatment because of their frequent interactions with them. Hence, it compels them to the level where their performance is compromised. Employees who face customer mistreatment feel ill-treated and develop the desire for revenge. Based on the social exchange and displaced revenge perspective, this study examined the relationship between customer mistreatment and coworker undermining, and individual-level resource-based moderator service rule commitment (SRC) for this relationship. An analysis of time-lagged, dyadic data (81 supervisors and 410 subordinates) from the Chinese service industry confirmed that customer mistreatment significantly predicted coworker undermining. In addition, in support of the resource perspective, employees' SRC effectively restricts an effect of customer mistreatment on coworker undermining. Finally, this study contributes to the customer mistreatment and coworker undermining literature by highlighting their relationship. This study also shows the importance of SRC in restraining the adverse effects of customer mistreatment.
Fulltext Nanomechanical, mechanical and microstructural characterization of electron beam welded Al2219-T6 tempered aerospace grade alloy: A comprehensive study

Hussain G, Shehbaz T, Alkahtani M, Khaliq UA, Wei H

Heliyon, 2024 Jan 15;10(1):e23835.
PMID: 38205289 DOI: 10.1016/j.heliyon.2023.e23835

As compared to traditional fusion welding processes, electron beam welding (EBW) is known to produce structurally robust microstructures and narrow heat-affected zone (HAZ) in metals. The process becomes more significant for the tempered alloys vulnerable to heat exposure. In the present investigation, Al 2219-T6 alloy was joined using the EBW process. The microstructural, mechanical, and nanomechanical characteristics of the resulting joint were investigated. EBW resulted in a narrow HAZ (22 μm) with a 430 mm fusion zone (FZ). A dendritic structure was observed in the FZ zone, while second-phase particles were absent indicating their dissolution during welding and interesting formation of Al2Cu mixture around the dendrites. The limited content of Cu in the base metal (BM) resulted in the formation of a solid solution in the FZ, along with the presence of fine equiaxed grains in the HAZ and equiaxed dendritic grains in the FZ zone. The X-ray diffraction analysis confirmed the absence of peaks corresponding to incoherent phases in the FZ. Compared to the BM, micro-hardness measurements revealed a 12.7 % increase in the hardness in the HAZ, while a significant decrease of approximately 19 % was observed in the FZ. The joint exhibited reduced tensile strength, ultimate strength by 42.2 %, and yield strength by 47.3 % when compared to the BM. The fracture analysis indicated a ductile failure mode with the presence of microvoids. Nano-indentation tests at various loads demonstrated a decrease in the nanohardness from the BM to the HAZ and FZ regions. Atomic force microscopy (AFM) analysis revealed significant pile-ups in the FZ, indicating the occurrence of plastic deformation during the welding process. The presented findings are valuable for the joint and structure design of Al -2219T6 alloy in particular and other Al alloys in general.
Impact of transportation infrastructure and urbanization on environmental pollution: evidence from novel wavelet quantile correlation approach

Malik MU, Rehman ZU, Sharif A, Anwar A

Environ Sci Pollut Res Int, 2024 Jan;31(2):3014-3030.
PMID: 38079035 DOI: 10.1007/s11356-023-31197-x

In terms of achieving sustainable development goals (SDGs), the developing economies are facing many issues, and one of the key issues is environmental degradation. Being a developing economy, Pakistan is also experiencing thought-provoking impacts of global warming and still far away from the ideal track of sustainable development. For addressing environment-related issue and achieving the targets of SDGs, a policy-level reorientation might be necessary. In this view, this study investigates the impact of economic growth, transport infrastructure, urbanization, financial development, and renewable energy consumption on CO2 emissions by using the data of Pakistan during 1990-2020. For this purpose, we use novel wavelet quantile correlation approach. The empirical results of wavelet quantile correlation approach demonstrate that economic growth, transport infrastructure, urbanization, and financial development are responsible for environmental pollution. Whereas, result also claims that renewable energy consumption is a useful tool for reducing environmental pollution in Pakistan. Moreover, the results of FMOLS approach show that 1% increase in economic growth, transportation infrastructure, urbanization, and financial development increases CO2 emissions by 0.240, 0.010, 0.478, and 0.102%, respectively. However, 1% increase in renewable energy usage reduces CO2 emission by 1.083%. Based on the empirical outcomes, this study proposes comprehensive policy framework for achieving the targets of SDG 7 (clean energy), SDG 8 (economic growth), SDG 11 (sustainable cities and communities), and SDG 13 (climate action).
Prognostic role of Neutrophil-Lymphocyte Ratio and Platelet-Lymphocyte Ratio in critically ill COVID-19 patients: A retrospective study

Wulandari W, Syahrul MZ, Ermayanti S, Rofinda ZD, Usman E, Kurnia D, et al.

Med J Malaysia, 2024 Nov;79(6):743-748.
PMID: 39614793

INTRODUCTION: Critical coronavirus disease (COVID-19) patients have a high mortality rate. To identify high-risk patients, first-level healthcare facilities can use the neutrophil-lymphocyte ratio (NLR) and the plateletlymphocyte ratio (PLR) as prognostic markers. We aimed to assess the NLR and the PLR profile in critically ill COVID-19 patients to predict disease severity.
MATERIALS AND METHODS: This descriptive retrospective study featured 221 patients diagnosed with clinically critical COVID-19 from August 2021 to March 2022 in the Intensive Care Unit (ICU) of RSUP Dr. M. Djamil, Padang, Indonesia. The study employed a total sampling technique to collect data from medical records in the hospital. Patients aged 18 years or older who underwent testing for leukocytes, platelets, neutrophils, and lymphocytes were included in the study. We analysed the data using descriptive univariate analysis. Then, the NLR and PLR of the patients were statistically compared based on comorbidities and coincidence.
RESULTS: According to the study, most patients with critically ill COVID-19 exhibited high levels of NLR (88.2%) and PLR (71.1%). The severe COVID-19 patients with comorbidity of kidney disease had the highest NLR (Mean ± SD) of 31.74 ± 27.95 (p-value <0.001) and the highest mean PLR (Mean ± SD) of 469.33 ± 362.95 (p-value 0.001).
CONCLUSION: Our findings showed a significantly higher NLR and PLR in patients with critically ill COVID-19, particularly in patients with comorbidity of kidney disease. Thus, elevated levels of NLR and PLR were identified as potential prognostic markers for predicting disease severity in COVID-19 patients, especially those with kidney comorbidity.
Fulltext Physical properties of abaca (Musa textilis nee) fibre reinforced high impact polystyrene (HIPS) composites

Agung Efriyo Hadi, Mohd. Sapuan Salit, Megat Mohd. Hamdan Megat Ahmad, Khairul Zaman Hj Mohd. Dahlan, Mustofa Usman

Pertanika Journal of Science & Technology, 2011;19(2):349-363.
MyJurnal

The physical properties by natural fibre have a great importance, specifically in the structural of natural fibre which reinforces matrix. Response surface methodology with Box-Behnken (BB) design of experiment was utilized to study water absorption and melt flow index (MFI) of abaca fibre reinforced high impact polystyrene (HIPS) composites. The design utilizes fraction of weight abaca fibre, maleic anhydride (MAH), and impact modifier to develop models for characteristic behaviours of water absorption and MFI of composites. Abaca fibre reinforced high impact polystyrene (HIPS) composites were produced with different fibre loadings (30, 40, and 50 wt%), different compositions of coupling agent, maleic anhydried (MAH) (1, 2, and 3 wt%) and different compositions of impact modifier (4, 5, 6 wt%). The individual optimum of water absorption was found when loading abaca fibre close to 34.61 wt%, maleic anhydride 1 wt%, and impact modifier 4.01 wt%. The individual optimum of melt flow index dealt with loading abaca fibre 36.71 wt%, maleic anhydride 3 wt% and impact modifier 4.02 wt%. Meanwhile, the optimum condition for water absorption of abaca fibre reinforced HIPS composites was followed by a decreasing trend of the value of melt flow index.
Fulltext Transcriptomic profiling of skeletal muscle from the Ts1Cje mouse model of Down syndrome suggests dysregulation of trisomic genes associated with neuromuscular junction signaling, oxidative stress and chronic inflammation

Leong, Melody Pui Yee, Usman Bala, Lim, Chai Ling, Rozita Rosli, Cheah, Pike-See, Ling, King-Hwa

Neuroscience Research Notes, 2018;1(1):21-41.
MyJurnal

Ts1Cje is a mouse model of Down syndrome (DS) with partial triplication of chromosome 16, which encompasses a high number of human chromosome 21 (HSA21) orthologous genes. The mouse model exhibits muscle weakness resembling hypotonia in DS individuals. The effect of extra gene dosages on muscle weakness or hypotonia in Ts1Cje and DS individuals remains unknown. To identify molecular dysregulation of the skeletal muscle, we compared the transcriptomic signatures of soleus and extensor digitorum longus (EDL) muscles between the adult Ts1Cje and disomic littermates. A total of 166 and 262 differentially expressed protein-coding genes (DEGs) were identified in the soleus and EDL muscles, respectively. The partial trisomy of MMU16 in Ts1Cje mice has a greater effect on gene expression in EDL. Top-down clustering analysis of all DEGs for represented functional ontologies revealed 5 functional clusters in soleus associated with signal transduction, development of reproductive system, nucleic acid biosynthesis, protein modification and metabolism as well as regulation of gene expression. On the other hand, only 3 functional clusters were observed for EDL namely neuron and cell development, protein modification and metabolic processes as well as ion transport. A total of 11 selected DEGs were validated using qPCR (disomic DEGs: Mansc1; trisomic DEGs: Itsn1, Rcan1, Synj1, Donson, Dyrk1a, Ifnar1, Ifnar2, Runx1, Sod1 and Tmem50b). The validated DEGs were implicated in neuromuscular junction signalling (Itsn1, Syn1), oxidative stress (Sod1, Runx1) and chronic inflammation processes (Runx1, Rcan1, Ifnar1, Ifnar2). Other validated DEGs have not been well-documented as involved in the skeletal muscle development or function, thus serve as interesting novel candidates for future investigations. To our knowledge, the study was the first attempt to determine the transcriptomic profiles of both soleus and EDL muscles in Ts1Cje mice. It provides new insights on the possible disrupted molecular pathways associated with hypotonia in DS individuals.
Fulltext Cellular function of satellite cells does not play a role in muscle weakness of adult Ts1Cje mice

Lim, Chai Ling, Usman Bala, Leong, Melody Pui-Yee, Johnson Stanslas, Rajesh Ramasamy, Ling, King-Hwa, et al.

Neuroscience Research Notes, 2018;1(1):3-10.
MyJurnal

Down syndrome (DS) is a genetic condition resulting from triplication of human chromosome (HSA)21. Besides intellectual disability, DS is frequently associated with hypotonia. Satellite cells are the resident cells that provides robust and remarkable regenerative capacity to the skeletal muscles, and its population size has been reported to be disease-associated. However, little is known about the population size of satellite cells in DS and the association of its intrinsic cellular functionality and hypotonia seen in DS. Here, we studied the Ts1Cje mouse, a DS murine model displays the muscle weakness characteristic. Satellite cell populations were immunostained with Pax7 and myonuclei numbers in the Ts1Cje extensor digitorum longus muscle were assessed. Their cellular function was further determined via in vitro assay in high-serum conditioned medium. Subsequently, the in vitro self-renewal, proliferative, and differentiation activities of these myogenic precursor cells were assessed after 24, 48, and 72h using Pax7, MyoD, and Ki67 immunomarkers. Our results showed that the population and functionality of Ts1Cje satellite cell did not differ significantly when compared to the wildtype cells isolated from disomic littermates. In conclusion, our findings indicated that intrinsic cellular functionality of the satellite cells, do not contribute to muscle weakness in Ts1Cje mouse.
Fulltext Heritability and genetic advance among chili pepper genotypes for heat tolerance and morphophysiological characteristics

Usman MG, Rafii MY, Ismail MR, Malek MA, Abdul Latif M

ScientificWorldJournal, 2014;2014:308042.
PMID: 25478590 DOI: 10.1155/2014/308042

High temperature tolerance is an important component of adaptation to arid and semiarid cropping environment in chili pepper. Two experiments were carried out to study the genetic variability among chili pepper for heat tolerance and morphophysiological traits and to estimate heritability and genetic advance expected from selection. There was a highly significant variation among the genotypes in response to high temperature (CMT), photosynthesis rate, plant height, disease incidence, fruit length, fruit weight, number of fruits, and yield per plant. At 5% selection intensity, high genetic advance as percent of the mean (>20%) was observed for CMT, photosynthesis rate, fruit length, fruit weight, number of fruits, and yield per plant. Similarly, high heritability (>60%) was also observed indicating the substantial effect of additive gene more than the environmental effect. Yield per plant showed strong to moderately positive correlations (r = 0.23-0.56) at phenotypic level while at genotypic level correlation coefficient ranged from 0.16 to 0.72 for CMT, plant height, fruit length, and number of fruits. Cluster analysis revealed eight groups and Group VIII recorded the highest CMT and yield. Group IV recorded 13 genotypes while Groups II, VII, and VIII recorded one each. The results showed that the availability of genetic variance could be useful for exploitation through selection for further breeding purposes.
Fulltext Capsaicin and dihydrocapsaicin determination in chili pepper genotypes using ultra-fast liquid chromatography

Usman MG, Rafii MY, Ismail MR, Malek MA, Latif MA

Molecules, 2014 May 21;19(5):6474-88.
PMID: 24853712 DOI: 10.3390/molecules19056474

Research was carried out to estimate the levels of capsaicin and dihydrocapsaicin that may be found in some heat tolerant chili pepper genotypes and to determine the degree of pungency as well as percentage capsaicin content of each of the analyzed peppers. A sensitive, precise, and specific ultra fast liquid chromatographic (UFLC) system was used for the separation, identification and quantitation of the capsaicinoids and the extraction solvent was acetonitrile. The method validation parameters, including linearity, precision, accuracy and recovery, yielded good results. Thus, the limit of detection was 0.045 µg/kg and 0.151 µg/kg for capsaicin and dihydrocapsaicin, respectively, whereas the limit of quantitation was 0.11 µg/kg and 0.368 µg/kg for capsaicin and dihydrocapsaicin. The calibration graph was linear from 0.05 to 0.50 µg/g for UFLC analysis. The inter- and intra-day precisions (relative standard deviation) were <5.0% for capsaicin and <9.9% for dihydrocapsaicin while the average recoveries obtained were quantitative (89.4%-90.1% for capsaicin, 92.4%-95.2% for dihydrocapsaicin), indicating good accuracy of the UFLC method. AVPP0705, AVPP0506, AVPP0104, AVPP0002, C05573 and AVPP0805 showed the highest concentration of capsaicin (12,776, 5,828, 4,393, 4,760, 3,764 and 4,120 µg/kg) and the highest pungency level, whereas AVPP9703, AVPP0512, AVPP0307, AVPP0803 and AVPP0102 recorded no detection of capsaicin and hence were non-pungent. All chili peppers studied except AVPP9703, AVPP0512, AVPP0307, AVPP0803 and AVPP0102 could serve as potential sources of capsaicin. On the other hand, only genotypes AVPP0506, AVPP0104, AVPP0002, C05573 and AVPP0805 gave a % capsaicin content that falls within the pungency limit that could make them recommendable as potential sources of capsaicin for the pharmaceutical industry.
Fulltext Synthesis, characterization, and antimicrobial properties of copper nanoparticles

Usman MS, El Zowalaty ME, Shameli K, Zainuddin N, Salama M, Ibrahim NA

Int J Nanomedicine, 2013;8:4467-79.
PMID: 24293998 DOI: 10.2147/IJN.S50837

Copper nanoparticle synthesis has been gaining attention due to its availability. However, factors such as agglomeration and rapid oxidation have made it a difficult research area. In the present work, pure copper nanoparticles were prepared in the presence of a chitosan stabilizer through chemical means. The purity of the nanoparticles was authenticated using different characterization techniques, including ultraviolet visible spectroscopy, transmission electron microscopy, X-ray diffraction, Fourier transform infrared spectroscopy, and field emission scanning electron microscopy. The antibacterial as well as antifungal activity of the nanoparticles were investigated using several microorganisms of interest, including methicillin-resistant Staphylococcus aureus, Bacillus subtilis, Pseudomonas aeruginosa, Salmonella choleraesuis, and Candida albicans. The effect of a chitosan medium on growth of the microorganism was studied, and this was found to influence growth rate. The size of the copper nanoparticles obtained was in the range of 2-350 nm, depending on the concentration of the chitosan stabilizer.
Fulltext Copper nanoparticles mediated by chitosan: synthesis and characterization via chemical methods

Usman MS, Ibrahim NA, Shameli K, Zainuddin N, Yunus WM

Molecules, 2012 Dec 14;17(12):14928-36.
PMID: 23242252 DOI: 10.3390/molecules171214928

Herein we report a synthesis of copper nanoparticles (Cu-NPs) in chitosan (Cts) media via a chemical reaction method. The nanoparticles were synthesized in an aqueous solution in the presence of Cts as stabilizer and CuSO(4)·5H(2)O precursor. The synthesis proceeded with addition of NaOH as pH moderator, ascorbic acid as antioxidant and hydrazine( )as the reducing agent. The characterization of the prepared NPs was done using ultraviolet-visible spectroscopy, which showed a 593 nm copper band. The Field Emission Scanning Electron Microscope (FESEM) images were also observed, and found to be in agreement with the UV-Vis result, confirming the formation of metallic Cu-NPs. The mean size of the Cu-NPs was estimated to be in the range of 35-75 nm using X-ray diffraction. XRD was also used in analysis of the crystal structure of the NPs. The interaction between the chitosan and the synthesized NPs was studied using Fourier transform infrared (FT-IR) spectroscopy, which showed the capping of the NPs by Cts.

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