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EEG/ERP adaptive noise canceller design with controlled search space (CSS) approach in cuckoo and other optimization algorithms

Ahirwal MK, Kumar A, Singh GK

IEEE/ACM Trans Comput Biol Bioinform, 2013 Nov-Dec;10(6):1491-504.
PMID: 24407307 DOI: 10.1109/TCBB.2013.119

This paper explores the migration of adaptive filtering with swarm intelligence/evolutionary techniques employed in the field of electroencephalogram/event-related potential noise cancellation or extraction. A new approach is proposed in the form of controlled search space to stabilize the randomness of swarm intelligence techniques especially for the EEG signal. Swarm-based algorithms such as Particles Swarm Optimization, Artificial Bee Colony, and Cuckoo Optimization Algorithm with their variants are implemented to design optimized adaptive noise canceler. The proposed controlled search space technique is tested on each of the swarm intelligence techniques and is found to be more accurate and powerful. Adaptive noise canceler with traditional algorithms such as least-mean-square, normalized least-mean-square, and recursive least-mean-square algorithms are also implemented to compare the results. ERP signals such as simulated visual evoked potential, real visual evoked potential, and real sensorimotor evoked potential are used, due to their physiological importance in various EEG studies. Average computational time and shape measures of evolutionary techniques are observed 8.21E-01 sec and 1.73E-01, respectively. Though, traditional algorithms take negligible time consumption, but are unable to offer good shape preservation of ERP, noticed as average computational time and shape measure difference, 1.41E-02 sec and 2.60E+00, respectively.
Immunoreactive LH in long-term frozen human urine samples

Singh GK, Jimenez M, Newman R, Handelsman DJ

Drug Test Anal, 2014 Apr;6(4):336-41.
PMID: 23606665 DOI: 10.1002/dta.1481

Urine provides a convenient non-invasive alternative to blood sampling for measurement of certain hormones. Urinary luteinizing hormone (LH) measurements have been used for endocrinology research and anti-doping testing. However, the commercially available LH immunoassays are developed and validated for human blood samples but not urine so that LH assays intended for use with urine samples need thorough validation. Therefore, the present study evaluated the measurement of urinary LH immunoreactivity using previously validated immunofluorometric (IF) and immunochemiluminometric (ICL) LH assays after prolonged frozen storage. LH was measured in serial urine samples following administration of a single injection of one of two doses of recombinant human chorionic hormone (rhCG) with assays run at the end of study (2008) and again after four years of frozen (-20 °C) storage where samples were stored without adding preservatives. The ICL assay showed quantitatively reproducible LH measurements after prolonged -20 °C storage. However, the IF immunoassay gave consistently lower LH levels relative to ICL (2008) with a further proportionate reduction after four years of sample storage (2012). Yet, both the assays displayed similar patterns of the time-course of urine LH measurement both before and after four years of frozen storage. In conclusion, we found that both immunoassays are suitable for urinary LH measurements with ICL assay being more robust for quantitative urinary LH measurement such as for anti-doping purposes, whereas the IF could be applicable for research studies where urine LH levels are compared within-study but not in absolute terms.
Histological changes in testes of rats treated with testosterone, nandrolone, and stanozolol

Mohd Mutalip SS, Surindar Singh GK, Mohd Shah A, Mohamad M, Mani V, Hussin SN

Iran J Reprod Med, 2013 Aug;11(8):653-8.
PMID: 24639803

Anabolic androgenic steroids (AAS) is being used in medical treatments, but AAS also was identified to have the risks of adverse effects towards patients and consumers health.
Pharmacokinetic-pharmacodynamic study of subcutaneous injection of depot nandrolone decanoate using dried blood spots sampling coupled with ultrapressure liquid chromatography tandem mass spectrometry assays

Singh GK, Turner L, Desai R, Jimenez M, Handelsman DJ

J Clin Endocrinol Metab, 2014 Jul;99(7):2592-8.
PMID: 24684468 DOI: 10.1210/jc.2014-1243

Testosterone (T) and nandrolone (N) esters require deep im injections by medical personnel but these often deposit injectate into sc fat so that more convenient sc self-administration may be feasible.
Requirement for specific gravity and creatinine adjustments for urinary steroids and luteinizing hormone concentrations in adolescents

Singh GK, Balzer BW, Desai R, Jimenez M, Steinbeck KS, Handelsman DJ

Ann. Clin. Biochem., 2015 Nov;52(Pt 6):665-71.
PMID: 25780247 DOI: 10.1177/0004563215580385

Urinary hormone concentrations are often adjusted to correct for hydration status. We aimed to determine whether first morning void urine hormones in growing adolescents require adjustments and, if so, whether urinary creatinine or specific gravity are better adjustments.
Fulltext Biopsychosocial approach to understanding predictors of depressive symptoms among men who have sex with men living with HIV in Selangor, Malaysia: A mixed methods study protocol

Mohamad Fisal ZA, Abdul Manaf R, Fattah Azman AZ, Karpal Singh GK

PLoS One, 2023;18(6):e0286816.
PMID: 37267403 DOI: 10.1371/journal.pone.0286816

BACKGROUND: Depression is the most common psychiatric disorder reported among patients living with Human Immunodeficiency Virus (HIV), resulting from the intricate combination of biological, psychological, and social factors. Biopsychosocial factors can significantly impact the psychological well-being of men who have sex with men (MSM) living with HIV through social stigma, access and compliance to care, economic insecurity, relationship difficulties, and risky behavior. Compared to MSM without HIV, MSM living with HIV were more likely to be depressed. Despite specific vulnerabilities and health needs, MSM living with HIV remain understudied and underserved in Malaysia owing to legal, ethical, and social challenges.
OBJECTIVE: This is merely a published protocol, not the findings of a future study. This study aims to determine and explain the predictors of depressive symptoms among MSM living with HIV. Specifically, this study wants to determine the association between depressive symptoms among MSM living with HIV and biological, psychosocial, and social factors. Finally, the mixed methods will answer to what extent the qualitative results confirm the quantitative results of the predictors of depressive symptoms among MSM living with HIV.
METHODS: The study has ethical approval from the Medical Research Ethics Committee (MREC) of the Ministry of Health (MOH) NMRR ID-21-02210-MIT. This study will apply an explanatory sequential mixed methods study design. It comprised two distinct phases: quantitative and qualitative study design for answering the research questions and hypothesis. This study will randomly recruit 941 MSM living with HIV in the quantitative phase, and at least 20 MSM living with HIV purposively will be selected in the qualitative phase. The study will be conducted in ten public Primary Care Clinics in Selangor, Malaysia. A self-administered questionnaire will gather the MSM's background and social, psychological, and biological factors that could be associated with depressive symptoms. For the quantitative study, descriptive analysis and simple logistic regression will be used for data analysis. Then, variables with a P value < 0.25 will be included in multiple logistic regression to measure the predictors of depressive symptoms. In the qualitative data collection, in-depth interviews will be conducted among those with moderate to severe depressive symptoms from the quantitative phase. The thematic analysis will be used for data analysis in the qualitative phase. Integration occurs at study design, method level, and later during interpretation and report writing.
RESULT: The quantitative phase was conducted between March 2022 to February 2023, while qualitative data collection is from March 2023 to April 2023, with baseline results anticipated in June 2023.
CONCLUSION: In combination, qualitative and quantitative research provides a better understanding of depressive symptoms among MSM living with HIV. The result could guide us to provide a comprehensive mental healthcare program toward Ending the AIDS epidemic by 2030.
Environmental enrichment improves cognitive function, learning, memory and anxiety-related behaviours in rodent models of dementia: Implications for future study

Mohd Sahini SN, Mohd Nor Hazalin NA, Srikumar BN, Jayasingh Chellammal HS, Surindar Singh GK

Neurobiol Learn Mem, 2024 Feb;208:107880.
PMID: 38103676 DOI: 10.1016/j.nlm.2023.107880

Environmental enrichment (EE) is a process of brain stimulation by modifying the surroundings, for example, by changing the sensory, social, or physical conditions. Rodents have been used in such experimental strategies through exposure to diverse physical, social, and exploration conditions. The present study conducted an extensive analysis of the existing literature surrounding the impact of EE on dementia rodent models. The review emphasised the two principal aspects that are very closely related to dementia: cognitive function (learning and memory) as well as psychological factors (anxiety-related behaviours such as phobias and unrealistic worries). Also highlighted were the mechanisms involved in the rodent models of dementia showing EE effects. Two search engines, PubMed and Science Direct, were used for data collection using the following keywords: environmental enrichment, dementia, rodent model, cognitive performance, and anxiety-related behaviour. Fifty-five articles were chosen depending on the criteria for inclusion and exclusion. The rodent models with dementia demonstrated improved learning and memory in the form of hampered inflammatory responses, enhanced neuronal plasticity, and sustained neuronal activity. EE housing also prevented memory impairment through the prevention of amyloid beta (Aβ) seeding formation, an early stage of Aβ plaque formation. The rodents subjected to EE were observed to present increased exploratory activity and exert less anxiety-related behaviour, compared to those in standard housing. However, some studies have proposed that EE intervention through exercise would be too mild to counteract the anxiety-related behaviour and risk assessment behaviour deficits in the Alzheimer's disease rodent model. Future studies should be conducted on old-aged rodents and the duration of EE exposure that would elicit the greatest benefits since the existing studies have been conducted on a range of ages and EE durations. In summary, EE had a considerable effect on dementia rodent models, with the most evident being improved cognitive function.
Fulltext Adult Personality and Its Relationship with Stress Level, Coping Mechanism and Academic Performance among Undergraduate Nursing Students

Mohamed Z, Jit Singh GK, Dediwadon NS, Mohamad Saleh NA, Jupri NN, Ganesan Y

Malays J Med Sci, 2022 Oct;29(5):117-125.
PMID: 36474539 DOI: 10.21315/mjms2022.29.5.12

BACKGROUND: Stress related to nursing education and clinical placement encounters by students since the beginning of their nursing course has been an issue of concern. This study aims to examine the prevalence of adult personality traits and their relationship with stress levels, coping mechanisms and academic performance among nursing students.
METHODS: This cross-sectional study was conducted among 92 nursing students at Universiti Kebangsaan Malaysia (UKM). The Big Five Inventory (BFI), Student Nurse Stress Index and Brief COPE instruments were used to measure the respondents' personality traits, stress level and coping mechanisms, respectively. Data were analysed using IBM SPSS version 26.
RESULTS: The most prevalent personality trait of the students was openness (mean = 33.58). Conscientiousness (r = -0.226, P = 0.030) and neuroticism (r = 0.326, P = 0.002) are significantly related to stress level. Extraversion (r = 0.219, P = 0.036), conscientiousness (r = 0.206, P = 0.049) and openness (r = 0.219, P = 0.036) show significant relationships with the approach coping mechanism, while agreeableness (r = -0.257, P = 0.013) and neuroticism (r = 0.297, P = 0.004) show significant relationships with the avoidant coping mechanism. However, no significant relationship was noted between personality traits and academic performance (r = 1.000, P > 0.05).
CONCLUSION: Knowledge of ones' personality traits may benefit students in understanding themselves and in using the best ways to cope with their stress while studying nursing.
Fulltext Urinary Sex Steroids and Anthropometric Markers of Puberty - A Novel Approach to Characterising Within-Person Changes of Puberty Hormones

Singh GK, Balzer BW, Kelly PJ, Paxton K, Hawke CI, Handelsman DJ, et al.

PLoS One, 2015;10(11):e0143555.
PMID: 26599397 DOI: 10.1371/journal.pone.0143555

The longitudinal relationships of within-individual hormone and anthropometric changes during puberty have not ever been fully described. The objectives of this study were to demonstrate that 3 monthly urine collection was feasible in young adolescents and to utilise liquid chromatography-tandem mass spectrometry assay methods for serum and urine testosterone (T), estradiol (E2) and luteinizing hormone (LH) in adolescents by relating temporal changes in urine and serum hormones over 12 months to standard measures of pubertal development.
Fulltext Human umbilical cord mesenchymal stem cell-derived extracellular vesicles ameliorate airway inflammation in a rat model of chronic obstructive pulmonary disease (COPD)

Ridzuan N, Zakaria N, Widera D, Sheard J, Morimoto M, Kiyokawa H, et al.

Stem Cell Res Ther, 2021 01 12;12(1):54.
PMID: 33436065 DOI: 10.1186/s13287-020-02088-6

BACKGROUND: Chronic obstructive pulmonary disease (COPD) is an incurable and debilitating chronic disease characterized by progressive airflow limitation associated with abnormal levels of tissue inflammation. Therefore, stem cell-based approaches to tackle the condition are currently a focus of regenerative therapies for COPD. Extracellular vesicles (EVs) released by all cell types are crucially involved in paracrine, extracellular communication. Recent advances in the field suggest that stem cell-derived EVs possess a therapeutic potential which is comparable to the cells of their origin.
METHODS: In this study, we assessed the potential anti-inflammatory effects of human umbilical cord mesenchymal stem cell (hUC-MSC)-derived EVs in a rat model of COPD. EVs were isolated from hUC-MSCs and characterized by the transmission electron microscope, western blotting, and nanoparticle tracking analysis. As a model of COPD, male Sprague-Dawley rats were exposed to cigarette smoke for up to 12 weeks, followed by transplantation of hUC-MSCs or application of hUC-MSC-derived EVs. Lung tissue was subjected to histological analysis using haematoxylin and eosin staining, Alcian blue-periodic acid-Schiff (AB-PAS) staining, and immunofluorescence staining. Gene expression in the lung tissue was assessed using microarray analysis. Statistical analyses were performed using GraphPad Prism 7 version 7.0 (GraphPad Software, USA). Student's t test was used to compare between 2 groups. Comparison among more than 2 groups was done using one-way analysis of variance (ANOVA). Data presented as median ± standard deviation (SD).
RESULTS: Both transplantation of hUC-MSCs and application of EVs resulted in a reduction of peribronchial and perivascular inflammation, alveolar septal thickening associated with mononuclear inflammation, and a decreased number of goblet cells. Moreover, hUC-MSCs and EVs ameliorated the loss of alveolar septa in the emphysematous lung of COPD rats and reduced the levels of NF-κB subunit p65 in the tissue. Subsequent microarray analysis revealed that both hUC-MSCs and EVs significantly regulate multiple pathways known to be associated with COPD.
CONCLUSIONS: In conclusion, we show that hUC-MSC-derived EVs effectively ameliorate by COPD-induced inflammation. Thus, EVs could serve as a new cell-free-based therapy for the treatment of COPD.