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Fulltext Medical professionalism videos on YouTube: Content exploration and appraisal of user engagement

Ahmad T, Sattar K, Akram A

Saudi J Biol Sci, 2020 Sep;27(9):2287-2292.
PMID: 32884409 DOI: 10.1016/j.sjbs.2020.06.007

Background: Social media has become the fastest growing platform for sharing and retrieving information and knowledge, and YouTube is one of the most popular and growing sources of health and educational information video-sharing website. But, videos on this open platform are not peer-assessed, therefore, the accessible data should be adequately assessed. Till date, no exploration and analysis for assessing the credibility and usefulness of Medical professionalism videos available on YouTube are conducted.
Objective: To analyze the video sources, contents and quality of YouTube videos about the topic of medical professionalism.
Methods: A systematic search was accomplished on YouTube videos during the period between March 1, 2020 and March 27, 2020. The phrases as significant words used throughout YouTube web search were 'Professionalism in Medical Education', Professionalism in medicine', 'Professionalism of medical students', 'Professionalism in healthcare'. 'Teaching professionalism', 'Attributes of professionalism'. The basic information collected for each video included author's/publisher's name, total number of watchers, likes, dislikes and positive and undesirable remarks. The videos were categorized into educationally useful and useless established on the content, correctness of the knowledge and the advices. Different variables were measured and correlated for the data analysis.YouTube website was searched the using keywords 'Professionalism in Medical Education', Professionalism in medicine', 'Professionalism of medical students', 'Professionalism in healthcare'. 'Teaching professionalism', and 'Attributes of professionalism'.
Results: After 2 rounds of screening by the subject experts and critical analysis of all the 137 YouTube videos, only 41 (29.92%) were identified as pertinent to the subject matter, i.e., educational type. After on expert viewing these 41 videos established upon our pre-set inclusion/exclusion criteria, only 17 (41.46%) videos were found to be academically valuable in nature.
Conclusion: Medical professionalism multimedia videos uploaded by the healthcare specialists or organizations on YouTube provided reliable information for medical students, healthcare workers and other professional. We conclude that YouTube is a leading and free online source of videos meant for students or other healthcare workers yet the viewers need to be aware of the source prior to using it for training learning.

Matched MeSH terms: Learning
Reflection of physiotherapy students in clinical placement: a qualitative study

Ayiesah Ramli, Aida Safra Ruslan, Noor Shahida Sukiman

Sains Malaysiana, 2012;41:787-793.

Clinical education provides students with opportunities to integrate knowledge and skills at progressively higher levels of performance. This study determined the significant events that undergraduate physiotherapy student reflects on during their clinical experiences as they learn to become a physiotherapist. A qualitative study using reflective instruments of structured debriefing sessions and diary writing was carried out. This involves 25 fourth-year students from the Faculty
of Health Sciences, UKM during their 12 weeks of clinical placements in 3 different modules (first semester). They were required to describe an event, its value and their reaction to it, and to discuss the effect of the new learning experience and how it would influence their respond in the future. Our findings confirmed that the process of writing a diary makes a considerable impact to the student experience during clinical placement. The subjects begin to construct a personal identity of becoming a physiotherapist through the process of developing confidence, confirmation of practices and assimilating of knowledge. In conclusion, the main themes generated from a reflective diary included their reflection of personal growth, on how they learnt in a clinical setting, and on the ethical and professional behaviors of themselves and colleagues. This provides the clinical educators with valuable information to design meaningful clinical learning experiences that would assist students to become a good physiotherapist for the future.

Matched MeSH terms: Learning; Problem-Based Learning
Multivariate relationship modeling using nested fuzzy cognitive map

Motlagh O, Papageorgiou E, Tang S, Zamberi Jamaludin

Sains Malaysiana, 2014;43:1781-1790.

Soft computing is an alternative to hard and classic math models especially when it comes to uncertain and incomplete data. This includes regression and relationship modeling of highly interrelated variables with applications in curve fitting, interpolation, classification, supervised learning, generalization, unsupervised learning and forecast. Fuzzy cognitive map (FCM) is a recurrent neural structure that encompasses all possible connections including relationships among inputs, inputs to outputs and feedbacks. This article examines a new methods for nonlinear multivariate regression using fuzzy cognitive map. The main contribution is the application of nested FCM structure to define edge weights in form of meaningful functions rather than crisp values. There are example cases in this article which serve as a platform to modelling even more complex engineering systems. The obtained results, analysis and comparison with similar techniques are included to show the robustness and accuracy of the developed method in multivariate regression, along with future lines of research.

Matched MeSH terms: Supervised Machine Learning; Unsupervised Machine Learning; Learning
Modelling exchange rates using regime switching models

Mohd Tahir Ismail, Zaidi Isa

Sains Malaysiana, 2006;35:55-62.

The behaviour of many financial time series cannot be modeled solely by linear time series model. Phenomena such as mean reversion, volatility of stock markets and structural breaks cannot be modelled implicitly using simple linear time series model. Thus, to overcome this problem, nonlinear time series models are typically designed to accommodate these nonlinear features in the data. In this paper, we use portmanteau test and structural change test to detect nonlinear feature in three ASEAN countries exchange rates (Malaysia, Singapore and Thailand). It is found that the null hypothesis of linearity is rejected and there is evidence of structural breaks in the exchange rates series. Therefore, the decision of using regime switching model in this study is justified. Using model selection criteria (AIC, SBC, HQC), we compare the in-sample fitting between two types of regime switching model. The two regime switching models we considered were the Self-Exciting Threshold Autoregressive (SETAR) model and the Markov switching Autoregressive (MS-AR) model where these models can explain the abrupt changes in a time series but differ as how they model the movement between regimes. From the AIC, SBC and HQC values, it is found that the MS -AR model is the best fitted model for all the return series. In addition, the regime switching model also found to perform better than simple autoregressive model in in-sample fitting. This result justified that nonlinear model give better in-sample fitting than linear model.

Matched MeSH terms: Learning
Predictor-corrector block iteration method for solving ordinary differential equations

Zanariah Abdul Majid, Mohamed Suleiman

Sains Malaysiana, 2011;40:1179-1186.

Predictor-corrector two point block methods are developed for solving first order ordinary differential equations (ODEs) using variable step size. The method will estimate the solutions of initial value problems (IVPs) at two points simultaneously. The existence multistep method involves the computations of the divided differences and integration coefficients when using the variable step size or variable step size and order. The block method developed will be presented as in the form of Adams Bashforth - Moulton type and the coefficients will be stored in the code. The efficiency of the predictor-corrector block method is compared to the standard variable step and order non block multistep method in terms of total number of steps, maximum error, total function calls and execution times.

Matched MeSH terms: Learning
Rational finite difference approximation of high order Accuracy for nonlinear two point boundary value problems

Pandey P

Sains Malaysiana, 2014;43:1105-1108.

In this paper, we present a new method for solving nonlinear general two point boundary value problems. A method based on finite differences and rational function approximation and we call this method as rational approximation method. A rational approximation method is applied to construct the numerical solution for two point boundary value problems. The novel method is tested on three model problems. Thus the numerical results obtained for these model problems show the performance and efficiency of the developed method.

Matched MeSH terms: Learning
New parallel R-point explicit block method for solving linear high-order ordinary differential equations directly

Zurni Omar, Mohamed Suleiman

Sains Malaysiana, 2009;38.

A new method called parallel R-point explicit block method for solving a single equation of higher order ordinary differential equation directly using a constant step size is developed. This method calculates the numerical solution at R point simultaneously is parallel in nature. Computational advantages are presented by comparing the results obtained with the new method with that of the conventional 1-point method. The numerical results show that the new method reduces the total number of steps and execution time. The accuracy of the parallel block and the conventional 1-point methods is comparable particularly when finer step sizes are used.

Matched MeSH terms: Learning
Discrete hopfield neural network in restricted maximum k-satisfiability logic programming

Mohd Shareduwan Mohd Kasihmuddin, Saratha Sathasivam, Mohd Asyraf Mansor

Sains Malaysiana, 2018;47:1327-1335.

Maximum k-Satisfiability (MAX-kSAT) consists of the most consistent interpretation that generate the maximum number
of satisfied clauses. MAX-kSAT is an important logic representation in logic programming since not all combinatorial
problem is satisfiable in nature. This paper presents Hopfield Neural Network based on MAX-kSAT logical rule. Learning
of Hopfield Neural Network will be integrated with Wan Abdullah method and Sathasivam relaxation method to obtain
the correct final state of the neurons. The computer simulation shows that MAX-kSAT can be embedded optimally in
Hopfield Neural Network.

Matched MeSH terms: Learning
Change in level of classroom lighting at a special education school distortion of vision and comparison of lighting at different lighting conditions

Wan Nur ‘Amirah Ibrahim, Zainora Mohammed, Norliza Mohamad Fadzil, Sumithira Narayanasamy, Mohd ‘Izzuddin Hairol

Sains Malaysiana, 2018;47:1835-1842.

Illumination is one of the important physical aspects that influences comfortability during learning session particularly
among visually impaired students. The purpose of this study was to determine changes in illumination level in classrooms
during learning session at Sekolah Menengah Pendidikan Khas (SMPK), Setapak. The second objective was to compare
the illumination level in the classrooms under three different lighting conditions: daylight only, with additional artificial
light and with removal of obstructions to daylight. Illumination levels in 17 classrooms was measured at one hour interval,
between 8 am to 1 pm for the first stage and 19 classrooms under three different lighting conditions from 11 am to 12 noon
for the second stage, using ILM1335 (ISO-TECH, Taiwan) digital luxmeter. Illumination level increased significantly from
8 am to 11 am (One-Way Repeated Measures ANOVA: F(2.14, 34.26)=76.49, p<0 .001) and was maximum at 1 pm. The
illumination level was highest for the condition of daylight with additional artificial light (One-Way Repeated Measures
ANOVA: F(2,34)=110.51, p<0.001) compared to other conditions. Illumination levels for daylight without obstruction
was significantly higher than daylight only (pairwise comparison: p=0.001). Classroom illumination level was lowest
in the early morning. However, classroom illumination can be increased either by removing the obstructions to daylight
or with additional artificial lighting.

Matched MeSH terms: Learning
Utilizing machine learning techniques to predict the blood-brain barrier permeability of compounds detected using LCQTOF-MS in Malaysian Kelulut honey

Edros R, Feng TW, Dong RH

SAR QSAR Environ Res, 2023;34(6):475-500.
PMID: 37409842 DOI: 10.1080/1062936X.2023.2230868

Current in silico modelling techniques, such as molecular dynamics, typically focus on compounds with the highest concentration from chromatographic analyses for bioactivity screening. Consequently, they reduce the need for labour-intensive in vitro studies but limit the utilization of extensive chromatographic data and molecular diversity for compound classification. Compound permeability across the blood-brain barrier (BBB) is a key concern in central nervous system (CNS) drug development, and this limitation can be addressed by applying cheminformatics with codeless machine learning (ML). Among the four models developed in this study, the Random Forest (RF) algorithm with the most robust performance in both internal and external validation was selected for model construction, with an accuracy (ACC) of 87.5% and 86.9% and area under the curve (AUC) of 0.907 and 0.726, respectively. The RF model was deployed to classify 285 compounds detected using liquid chromatography quadrupole time-of-flight mass spectrometry (LCQTOF-MS) in Kelulut honey; of which, 140 compounds were screened with 94 descriptors. Seventeen compounds were predicted to permeate the BBB, revealing their potential as drugs for treating neurodegenerative diseases. Our results highlight the importance of employing ML pattern recognition to identify compounds with neuroprotective potential from the entire pool of chromatographic data.

Matched MeSH terms: Machine Learning
Fulltext Perceptions of medical students regarding community-based teaching experiences: an observation from Bangladesh

Ahmed SMM, Hasan MN, Kabir R, Arafat SMY, Rahman S, Haque M, et al.

Rural Remote Health, 2019 08;19(3):4614.
PMID: 31400766 DOI: 10.22605/RRH4614

INTRODUCTION: Community orientation in medical education, which prepares medical students to become more effective practitioners, is now a global movement. Many medical schools around the world have adopted the concept as the main curricular framework in order to align learning programs with the needs of the community and the learner. Despite many changes over the past few decades, many improvements are still needed in medical education in Bangladesh. This study investigated medical students' perceptions of the community-based learning experiences incorporated into the Bachelor of Medicine, Bachelor of Surgery (MBBS) degree at Uttara Adhunik Medical College, Dhaka (UAMC), Bangladesh.
METHODS: A total of 135 students from three undergraduate year levels of the MBBS degree at UAMC, Dhaka, Bangladesh, undertook study tours (community-based teaching, CBT) as a part of a community medicine course and visited a medical college, two rural health centres and a meteorology centre in the Cox's Bazar district, 400 km from Dhaka city. A questionnaire was used to assess the perceptions of students regarding the administration, organisation and learning experiences of the study tours. Students were required to write reports, present their findings and answer questions in their examinations related to the study tours and CBT.
RESULTS: The majority of the students agreed or strongly agreed that the tour was a worthwhile (93%) and enjoyable (95%) learning experience that helped them to understand rural health issues (91%). More than half of the students reported that the study tours increased their awareness about common rural health problems (54%) and provided a wider exposure to medicine (61%). Only 41% of students reported that the study tour increased their interest in undertake training in a rural area. A substantial number of students also expressed their concerns about the planning, length, resources, finance and organisation of the study tours.
CONCLUSIONS: Overall, the study tours had a positive effect, enhancing students' awareness and understanding of common rural health problems. As study tours failed to increase the motivation of the students (approximately 60%) to work in rural areas, CBT in the medical curriculum should be reviewed and implemented using effective and evidence-based models to promote interest among medical students to work in rural and underserved or unserved areas.

Matched MeSH terms: Problem-Based Learning/organization & administration*
Using artificial intelligence methods for systematic review in health sciences: A systematic review

Blaizot A, Veettil SK, Saidoung P, Moreno-Garcia CF, Wiratunga N, Aceves-Martins M, et al.

Res Synth Methods, 2022 May;13(3):353-362.
PMID: 35174972 DOI: 10.1002/jrsm.1553

The exponential increase in published articles makes a thorough and expedient review of literature increasingly challenging. This review delineated automated tools and platforms that employ artificial intelligence (AI) approaches and evaluated the reported benefits and challenges in using such methods. A search was conducted in 4 databases (Medline, Embase, CDSR, and Epistemonikos) up to April 2021 for systematic reviews and other related reviews implementing AI methods. To be included, the review must use any form of AI method, including machine learning, deep learning, neural network, or any other applications used to enable the full or semi-autonomous performance of one or more stages in the development of evidence synthesis. Twelve reviews were included, using nine different tools to implement 15 different AI methods. Eleven methods were used in the screening stages of the review (73%). The rest were divided: two in data extraction (13%) and two in risk of bias assessment (13%). The ambiguous benefits of the data extractions, combined with the reported advantages from 10 reviews, indicating that AI platforms have taken hold with varying success in evidence synthesis. However, the results are qualified by the reliance on the self-reporting of the review authors. Extensive human validation still appears required at this stage in implementing AI methods, though further evaluation is required to define the overall contribution of such platforms in enhancing efficiency and quality in evidence synthesis.

Matched MeSH terms: Machine Learning
Fulltext Conditional Learning Deficits in Children with ADHD can be Reduced Through Reward Optimization and Response-Specific Reinforcement

De Meyer H, Tripp G, Beckers T, van der Oord S

Res Child Adolesc Psychopathol, 2021 09;49(9):1165-1178.
PMID: 33792820 DOI: 10.1007/s10802-021-00781-5

When children with ADHD are presented with behavioral choices, they struggle more than Typically Developing [TD] children to take into account contextual information necessary for making adaptive choices. The challenge presented by this type of behavioral decision making can be operationalized as a Conditional Discrimination Learning [CDL] task. We previously showed that CDL is impaired in children with ADHD. The present study explores whether this impairment can be remediated by increasing reward for correct responding or by reinforcing correct conditional choice behavior with situationally specific outcomes (Differential Outcomes). An arbitrary Delayed Matching-To-Sample [aDMTS] procedure was used, in which children had to learn to select the correct response given the sample stimulus presented (CDL). We compared children with ADHD (N = 45) and TD children (N = 49) on a baseline aDMTS task and sequentially adapted the aDMTS task so that correct choice behavior was rewarded with a more potent reinforcer (reward manipulation) or with sample-specific (and hence response-specific) reinforcers (Differential Outcomes manipulation). At baseline, children with ADHD performed significantly worse than TD children. Both manipulations (reward optimization and Differential Outcomes) improved performance in the ADHD group, resulting in a similar level of performance to the TD group. Increasing the reward value or the response-specificity of reinforcement enhances Conditional Discrimination Learning in children with ADHD. These behavioral techniques may be effective in promoting the learning of adaptive behavioral choices in children with ADHD.

Matched MeSH terms: Learning
A systematic review of behaviour change techniques in pharmacist-delivered self-management interventions towards patients with chronic obstructive pulmonary disease

Jamil N, Zainal ZA, Alias SH, Chong LY, Hashim R

Res Social Adm Pharm, 2023 Aug;19(8):1131-1145.
PMID: 37202279 DOI: 10.1016/j.sapharm.2023.05.006

BACKGROUND: Self-management interventions often employ behaviour change techniques in order to produce desired target behaviours that are necessary for day-to-day living with a chronic disease. Despite the large number of self-management interventions for patients with chronic obstructive pulmonary disease (COPD), previously reported interventions have been typically delivered by healthcare providers other than the pharmacist.
OBJECTIVE: This systematic review examined the components of pharmacists-delivered COPD self-management interventions according to an established taxonomy of behaviour change techniques (BCTs).
METHODS: A systematic search was conducted on PubMed, ScienceDirect, OVID, and Google Scholar from January 2011 to December 2021 for studies of pharmacist-delivered self-management interventions in COPD patients.
RESULTS: A total of seventeen studies of intervention were eligible for inclusion in the narrative review. Interventions were educational and were delivered individually and face-to-face for the first session. Across studies, pharmacists spent an average of 35 min on the first meeting and had an average of 6 follow-up sessions. Recurrent BCTs in pharmacist interventions were "Information on the health consequence", "Feedback on behaviour", "Instruction on how to perform a behaviour", "Demonstration of the behaviour" and "Behavioural practice/rehearsal".
CONCLUSIONS: Pharmacists have provided interventions towards improving health behaviours, especially on adherence and usage of inhaler devices for patients with COPD. Future self-management interventions should be designed using the identified BCTs for the improvement of COPD self-management and disease outcomes.

Matched MeSH terms: Learning
Visual-perceptual-kinesthetic inputs on influencing writing performances in children with handwriting difficulties

Tse LF, Thanapalan KC, Chan CC

Res Dev Disabil, 2014 Feb;35(2):340-7.
PMID: 24333804 DOI: 10.1016/j.ridd.2013.11.013

This study investigated the role of visual-perceptual input in writing Chinese characters among senior school-aged children who had handwriting difficulties (CHD). The participants were 27 CHD (9-11 years old) and 61 normally developed control. There were three writing conditions: copying, and dictations with or without visual feedback. The motor-free subtests of the Developmental Test of Visual Perception (DTVP-2) were conducted. The CHD group showed significantly slower mean speeds of character production and less legibility of produced characters than the control group in all writing conditions (ps<0.001). There were significant deteriorations in legibility from copying to dictation without visual feedback. Nevertheless, the Group by Condition interaction effect was not statistically significant. Only position in space of DTVP-2 was significantly correlated with the legibility among CHD (r=-0.62, p=0.001). Poor legibility seems to be related to the less-intact spatial representation of the characters in working memory, which can be rectified by viewing the characters during writing. Visual feedback regarding one's own actions in writing can also improve legibility of characters among these children.

Matched MeSH terms: Learning Disorders/physiopathology*
The use of graphic rules in grade one to help identify children at risk of handwriting difficulties

Khalid PI, Yunus J, Adnan R, Harun M, Sudirman R, Mahmood NH

Res Dev Disabil, 2010 Nov-Dec;31(6):1685-93.
PMID: 20554150 DOI: 10.1016/j.ridd.2010.04.005

Previous researches on elementary grade handwriting revealed that pupils employ certain strategy when writing or drawing. The relationship between this strategy and the use of graphic rules has been documented but very little research has been devoted to the connection between the use of graphic rules and handwriting proficiency. Thus, this study was conducted to investigate the relative contribution of the use of graphic rules to the writing ability. A sample of 105 first graders who were average printers and 65 first graders who might experience handwriting difficulty, as judged by their teachers, of a normal primary school were individually tested on their use of graphic rules. It has been found that pupils who are below average printers use more non-analytic strategy than average printers to reproduce the figures. The results also reveal that below average printers do not acquire the graphic principles that foster an analytic approach to production skills. Although the findings are not sufficient to allow definitive conclusions about handwriting ability, it can be considered as one of the screening measures in identifying pupils who are at risk of handwriting difficulties.

Matched MeSH terms: Learning Disorders/diagnosis*; Learning Disorders/epidemiology
Extraction of dynamic features from hand drawn data for the identification of children with handwriting difficulty

Khalid PI, Yunus J, Adnan R

Res Dev Disabil, 2010 Jan-Feb;31(1):256-62.
PMID: 19854613 DOI: 10.1016/j.ridd.2009.09.009

Studies have shown that differences between children with and without handwriting difficulties lie not only in the written product (static data) but also in dynamic data of handwriting process. Since writing system varies among countries and individuals, this study was conducted to determine the feasibility of using quantitative outcome measures of children's drawing to identify children who are at risk of handwriting difficulties. A sample of 143 first graders of a normal primary school was investigated regarding their handwriting ability. The children were divided into two groups: test and control. Ten children from test group and 40 children from control group were individually tested for their Visual Motor Integration skills. Analysis on dynamic data indicated significant differences between the two groups in temporal and spatial measures of the drawing task performance. Thus, kinematic analysis of children's drawing is feasible to provide performance characteristic of handwriting ability, supporting its use in screening for handwriting difficulty.

Matched MeSH terms: Learning Disorders/diagnosis*; Learning Disorders/psychology
Fulltext Effects of psychological ownership on teachers' beliefs about a cloud-based virtual learning environment

Yim JS, Moses P, Azalea A

Res Pract Technol Enhanc Learn, 2018;13(1):13.
PMID: 30595741 DOI: 10.1186/s41039-018-0081-0

Perceived usefulness and perceived ease of use constitute important belief factors when technology adoption decisions are made within a non-mandatory setting. This paper investigated the role played by psychological ownership in shaping teachers' beliefs about using a cloud-based virtual learning environment (VLE). Psychological ownership is increasingly becoming a relevant phenomenon in technology adoption research, where people can feel psychologically attached to a particular technology. The study proposed that such phenomenon can also occur when using a VLE, and a hypothesised model with six constructs was tested with 629 Malaysian teachers from 21 schools. Results from structural equation modelling-partial least squares analysis found teachers' experiences with the VLE significantly influenced psychological ownership, which in turn significantly predicted perceived usefulness and perceived ease of use of the VLE. Overall, the model possesses predictive relevance for the outcome predictors as indicated by Stone-Geisser's Q2, and accounted for 61.6% of variance in perceived usefulness and 62.0% of variance in perceived ease of use. This study provides insights into the motivation behind teachers' beliefs which are shaped by their experiences with the VLE. Implications for theory and practice were discussed based on the insights of the study.

Matched MeSH terms: Learning
Fulltext Effects of COVID-19 in E-learning on higher education institution students: the group comparison between male and female

Shahzad A, Hassan R, Aremu AY, Hussain A, Lodhi RN

Qual Quant, 2020 Aug 04.
PMID: 32836471 DOI: 10.1007/s11135-020-01028-z

In response to the emerging and ever solution to the COVID-19 outbreak. This study proposes a theoretical framework based on literature and model to determined E-learning portal success. The study compared males and females to E-learning portal usage. The study objective is to check the difference between male and female E-learning portals' accessibility among the students' perspective. The study included service quality, system quality, information quality, user satisfaction, system use, and E-learning portal success. The empirical data of 280 students participated from the different universities of Malaysia through google surveys analyzed using the Partial Least Squares Structural Equation Modelling. The study further divided the full model into two domains, which are female and male. In the male model, information quality and system quality have direct relationships with user satisfaction. Information quality also supported the relationship with system use. At the same time, there is a positive relationship between user satisfaction and E-learning portals. Likewise, in the female model, E-service quality and Information quality both are supported by system use and user satisfaction. Similarly, system quality has a positive relationship with user satisfaction, and user satisfaction has a positive relationship with E-learning portals. The study will be further helpful for the Malaysian universities policy-makers such as top management, ministry of higher education, Malaysian universities union in designing the policies and programs on E-learning Portal Success in the country. The findings of the study reveal that males and females have a different level of in terms of usage of towards E-learning portals in Malaysian Universities.

Matched MeSH terms: Learning
Discriminative stimulus properties of mitragynine (kratom) in rats

Harun N, Hassan Z, Navaratnam V, Mansor SM, Shoaib M

Psychopharmacology (Berl), 2015 Jul;232(13):2227-38.
PMID: 25616583 DOI: 10.1007/s00213-015-3866-5

RATIONALE: Mitragynine (MG) is the primary active alkaloid extracted from the leaves of Mitragyna speciosa or kratom and exhibits pharmacological activities mediated by opioid receptors. The plant has been traditionally used for its opium and psychostimulant-like effects to increase work efficiency or as a substitute in the self-treatment of opiate addiction.
OBJECTIVES: The present study was performed to investigate the discriminative stimulus effects of MG in rats. The pharmacological mechanism of MG action and its derivative, 7-hydroxymitragynine (7-HMG) with a specific focus on opioid receptor involvement was examined in rats trained to discriminate morphine from vehicle. In order to study the dual actions of MG, the effect of cocaine substitution to the MG discriminative stimulus was also performed in MG-trained rats.
METHODS: Male Sprague Dawley rats were trained to discriminate MG from vehicle in a two-lever drug discrimination procedure under a tandem variable-interval (VI 60') fixed-ratio (FR 10) schedule of food reinforcement.
RESULTS: Rats acquired the MG discrimination (15.0 mg/kg, i.p.) which was similar to the acquisition of morphine discrimination (5.0 mg/kg, i.p.) in another group of rats. MG substituted fully to the morphine discriminative stimulus in a dose-dependent manner, suggesting pharmacological similarities between the two drugs. The administration of 7-HMG derivative in 3.0 mg/kg (i.p.) dose engendered full generalisation to the morphine discriminative stimulus. In addition, the MG stimulus also partially generalised to cocaine (10.0 mg/kg, i.p.) stimulus.
CONCLUSION: The present study demonstrates that the discriminative stimulus effect of MG possesses both opioid- and psychostimulant-like subjective effects.

Matched MeSH terms: Discrimination Learning/drug effects*; Discrimination Learning/physiology

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