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  1. Yusof SR, Avdeef A, Abbott NJ
    Eur J Pharm Sci, 2014 Dec 18;65:98-111.
    PMID: 25239510 DOI: 10.1016/j.ejps.2014.09.009
    In vitro blood-brain barrier (BBB) models from primary brain endothelial cells can closely resemble the in vivo BBB, offering valuable models to assay BBB functions and to screen potential central nervous system drugs. We have recently developed an in vitro BBB model using primary porcine brain endothelial cells. The model shows expression of tight junction proteins and high transendothelial electrical resistance, evidence for a restrictive paracellular pathway. Validation studies using small drug-like compounds demonstrated functional uptake and efflux transporters, showing the suitability of the model to assay drug permeability. However, one limitation of in vitro model permeability measurement is the presence of the aqueous boundary layer (ABL) resulting from inefficient stirring during the permeability assay. The ABL can be a rate-limiting step in permeation, particularly for lipophilic compounds, causing underestimation of the permeability. If the ABL effect is ignored, the permeability measured in vitro will not reflect the permeability in vivo. To address the issue, we explored the combination of in vitro permeability measurement using our porcine model with the pKa(FLUX) method in pCEL-X software to correct for the ABL effect and allow a detailed analysis of in vitro (transendothelial) permeability data, Papp. Published Papp using porcine models generated by our group and other groups are also analyzed. From the Papp, intrinsic transcellular permeability (P0) is derived by simultaneous refinement using a weighted nonlinear regression, taking into account permeability through the ABL, paracellular permeability and filter restrictions on permeation. The in vitro P0 derived for 22 compounds (35 measurements) showed good correlation with P0 derived from in situ brain perfusion data (r(2)=0.61). The analysis also gave evidence for carrier-mediated uptake of naloxone, propranolol and vinblastine. The combination of the in vitro porcine model and the software analysis provides a useful tool to better predict BBB permeability in vivo and gain better mechanistic information about BBB permeation.
  2. Yusof SR, Abbott NJ, Avdeef A
    Eur J Pharm Sci, 2017 Aug 30;106:274-286.
    PMID: 28614733 DOI: 10.1016/j.ejps.2017.06.016
    Most studies of blood-brain barrier (BBB) permeability and transport are conducted at a single pH, but more detailed information can be revealed by using multiple pH values. A pH-dependent biophysical model was applied to the mechanistic analysis of published pH-dependent BBB luminal uptake data from three opioid derivatives in rat: pentazocine (Suzuki et al., 2002a, 2002b), naloxone (Suzuki et al., 2010a), and oxycodone (Okura et al., 2008). Two types of data were processed: in situ brain perfusion (ISBP) and brain uptake index (BUI). The published perfusion data were converted to apparent luminal permeability values, Papp, and analyzed by the pCEL-X program (Yusof et al., 2014), using the pH-dependent Crone-Renkin equation (pH-CRE) to determine the impact of cerebrovascular flow on the Michaelis-Menten transport parameters (Avdeef and Sun, 2011). For oxycodone, the ISBP data had been measured at pH7.4 and 8.4. The present analysis indicates a 7-fold lower value of the cerebrovascular flow velocity, Fpf, than that expected in the original study. From the pyrilamine-inhibited data, the flow-corrected passive intrinsic permeability value was determined to be P0=398×10-6cm·s-1. The uptake data indicate that the neutral form of oxycodone is affected by a transporter at pH8.4. The extent of the cation uptake was less certain from the available data. For pentazocine, the brain uptake by the BUI method had been measured at pH5.5, 6.5, and 7.4, in a concentration range 0.1-40mM. Under similar conditions, ISBP data were also available. The pH-CRE determined values of Fpf from both methods were nearly the same, and were smaller than the expected value in the original publication. The transport of the cationic pentazocine was not fully saturated at pH5.5 at 40mM. The transport of the neutral species at pH7.4 appeared to reach saturation at 40mM pentazocine concentration, but not at 12mM. In the case of naloxone, a pH-dependent Michaelis-Menten equation (pH-MME) analysis of the data indicated a smooth sigmoidal transition from a higher capacity uptake process affecting cationic naloxone (pH5.0-7.0) to a lower capacity uptake process affecting the neutral drug (pH8.0-8.5), with cross-over point near pH7.4. Evidently, measurements at multiple pH values can reveal important information about both cerebrovascular flow and BBB transport kinetics.
  3. Arifin SRBM, Cheyne H, Maxwell M, Yousuf A
    PMID: 34040649 DOI: 10.2174/1745017902117010010
    Objectives: Early detection and intervention for Maternal Postnatal Depression (PND) are imperative to prevent devastating consequences for mothers, babies, and families. However, there are no guidelines that explicitly focus on the management of PND in Malaysia. Consequently, it is unclear whether women with PND are receiving proper care and treatment. Therefore, this study aimed to explore Malaysian Women's experience in managing PND symptoms.

    Methods: A qualitative study was conducted among 33 women attending Maternal and Child Health (MCH) clinics in Kuala Lumpur. Data were obtained through a face-to-face semi-structured interview and analysed using framework analysis.

    Results: The women considered PND as a personal and temporary issue. Therefore, professional care was deemed unnecessary for them. Additionally, all Malay women considered religious approach as their primary coping strategy for PND. However, this was not the case for most Indian and Chinese women.

    Conclusion: The findings of this study indicated that women did not acknowledge the roles of Healthcare Practitioners (HCPs) in alleviating their emotional distress.Also, they perceived PND as a personal problem and less serious emotional condition. It is due to this perception that the women adopted self-help care as their primary coping strategy for PND. However, the coping strategy varied between different cultures. These findings underscore the importance of HCPs' proactive action to detect and alleviate PND symptoms as their attitude towards PND may influence Women's help-seeking behaviour.

  4. Hanapi NA, Chear NJ, Azizi J, Yusof SR
    Front Pharmacol, 2021;12:751656.
    PMID: 34867362 DOI: 10.3389/fphar.2021.751656
    Parallel to the growing use of kratom, there is a wealth of evidence from self-report, preclinical, and early clinical studies on therapeutic benefits of its alkaloids in particular for treating pain, managing substance use disorder, and coping with emotional or mental health conditions. On the other hand, there are also reports on potential health risks concerning kratom use. These two aspects are often discussed in reviews on kratom. Here, we aim to highlight specific areas that are of importance to give insights into the mechanistic of kratom alkaloids pharmacological actions. This includes their interactions with drug-metabolizing enzymes and predictions of clinical drug-drug interactions, receptor-binding properties, interactions with cellular barriers in regards to barrier permeability, involvement of membrane transporters, and alteration of barrier function when exposed to the alkaloids.
  5. Tan WL, Siti R, Shahfini I, Zuraidah A
    Med J Malaysia, 2015 Oct;70(5):307-11.
    PMID: 26556121 MyJurnal
    BACKGROUND: Antibiotic resistance is a rising problem in Malaysia. For instance, high antibiotic prescribing rate for upper respiratory tract infection and inappropriate choice of antibiotic is a significant healthcare concern in Malaysia. Our main objective was to study knowledge, attitude and practice of antibiotic prescribing among medical officers in Kedah, Malaysia.
    METHODS: A cross sectional study was conducted in outpatient departments of health clinics and hospitals in Kedah from June 2013 until December 2013. Sample size was 118 and systematic sampling was conducted. Research tool used was a validated questionnaire from studies conducted in Congo and Peru.
    RESULTS: Response rate was 84.8%. Majority of our respondents were female doctors (71.0%), local graduates (63.0%), and practiced for 4 years or less (61.0%). 52.0% of the respondents prescribed antibiotics more than once daily. Mean knowledge score on antibiotics was 5.31 ±1.19 (95% CI: 5.06; 5.54). More than half (62.0%) of our respondents were confident in antibiotic prescribing and there were merely 18.0% of them consulted any colleagues prior to prescription. There was a significant difference in frequency of antibiotic prescribing between junior doctors and senior doctors (P-value: 0.036). In addition, there was also a significant association between frequency of antibiotic prescribing and awareness of antibiotic resistance in their daily practice. (P-value: 0.002).
    CONCLUSION: Knowledge on antibiotic was moderate among our medical officers and antibiotic prescribing was frequent. Training and courses on appropriate antibiotic prescribing should be emphasized to ensure the best practice in antibiotic prescription.
    Study site: Klinik Kesihatan, outpatient clinics, district hospital, general hospital, Kedah, Malaysia
  6. Rahman RA, Hussaini HM, Rahman NA, Rahman SR, Nor GM, Ai Idrus SM, et al.
    Eur J Trauma Emerg Surg, 2007 Feb;33(1):90-5.
    PMID: 26815981 DOI: 10.1007/s00068-007-5154-5
    The objective of this study was to determine the demographic data as well as other relevant data pertaining to the management of patients with maxillofacial injury in a Malaysian government regional hospital.
  7. Liew KF, Hanapi NA, Chan KL, Yusof SR, Lee CY
    J Pharm Sci, 2017 02;106(2):502-510.
    PMID: 27855959 DOI: 10.1016/j.xphs.2016.10.006
    Previously, several aurone derivatives were identified with promising neuroprotective activities. In developing these compounds to target the central nervous system (CNS), an assessment of their blood-brain barrier (BBB) permeability was performed using in vitro BBB models: parallel artificial membrane permeability assay-BBB which measures passive permeability and primary porcine brain endothelial cell model which enables determination of the involvement of active transport mechanism. Parallel artificial membrane permeability assay-BBB identified most compounds with high passive permeability, with 3 aurones having exceptional Pevalues highlighting the importance of basic amine moieties and optimal lipophilicity for good passive permeability. Bidirectional permeability assays with porcine brain endothelial cell showed a significant net influx permeation of the aurones indicating a facilitated uptake mechanism in contrast to donepezil, a CNS drug included in the evaluation which only displayed passive permeation. From pH-dependent permeability assay coupled with data analysis using pCEL-X software, intrinsic transcellular permeability (Po) of a representative aurone 4-3 was determined, considering factors such as the aqueous boundary layer that may hinder accurate in vitro to in vivo correlation. The Po value determined supported the in vivo feasibility of the aurone as a CNS-active compound.
  8. Hanapi NA, Mohamad Arshad AS, Abdullah JM, Tengku Muhammad TS, Yusof SR
    J Pharm Sci, 2021 02;110(2):698-706.
    PMID: 32949562 DOI: 10.1016/j.xphs.2020.09.015
    Neurotherapeutic potentials of Centella asiatica and its reputation to boost memory, prevent cognitive deficits and improve brain functions are widely acknowledged. The plant's bioactive compounds, i.e. asiaticoside, madecassoside and asiatic acid were reported to have central nervous system (CNS) actions, particularly in protecting the brain against neurodegenerative disorders. Hence, it is important for these compounds to cross the blood-brain barrier (BBB) to be clinically effective therapeutics. This study aimed to explore the capability of asiaticoside, madecassoside and asiatic acid to cross the BBB using in vitro BBB model from primary porcine brain endothelial cells (PBECs). Our findings showed that asiaticoside, madecassoside and asiatic acid are highly BBB permeable with apparent permeability (Papp) of 70.61 ± 6.60, 53.31 ± 12.55 and 50.94 ± 10.91 × 10-6 cm/s respectively. No evidence of cytotoxicity and tight junction disruption of the PBECs were observed in the presence of these compounds. Asiatic acid showed cytoprotective effect towards the PBECs against oxidative stress. This study reported for the first time that Centella asiatica compounds demonstrated high capability to cross the BBB, comparable to central nervous system drugs, and therefore warrant further development as therapeutics for the treatment of neurodegenerative diseases.
  9. Makhsin SR, Goddard NJ, Gupta R, Gardner P, Scully PJ
    Anal Chem, 2020 11 17;92(22):14907-14914.
    PMID: 32378876 DOI: 10.1021/acs.analchem.0c00586
    The metal-clad leaky waveguide (MCLW) is an optical biosensor consisting of a metal layer and a low index waveguide layer on a glass substrate. This label-free sensor measures refractive index (RI) changes within the waveguide layer. This work shows the development and optimization of acrylate based-hydrogel as the waveguide layer formed from PEG diacrylate (PEGDA, Mn 700), PEG methyl ether acrylate (PEGMEA, Mn 480), and acrylate-PEG2000-NHS fabricated on a substrate coated with 9.5 nm of titanium. The acrylate-based hydrogel is a synthetic polymer, so properties such as optical transparency, porosity, and hydrogel functionalization by a well-controlled reactive group can be tailored for immobilization of the bioreceptor within the hydrogel matrix. The waveguide sensor demonstrated an equal response to solutions of identical RI containing small (glycerol) and large (bovine serum albumin; BSA) analyte molecules, indicating that the hydrogel waveguide film is highly porous to both sizes of molecule, thus potentially allowing penetration of a range of analytes within the porous matrix. The final optimized MCLW chip was formed from a total hydrogel concentration of 40% v/v of PEGMEA-PEGDA (Mn 700), functionalized with 2.5% v/v of acrylate-PEG2000-NHS. The sensor generated a single-moded waveguide signal with a RI sensitivity of 128.61 ± 0.15° RIU-1 and limit of detection obtained at 2.2 × 10-6 RIU with excellent signal-to-noise ratio for the glycerol detection. The sensor demonstrated RI detection by monitoring changes in the out-coupled angle resulting from successful binding of d-biotin to streptavidin immobilized on functionalized acrylate hydrogel, generating a binding signal of (12.379 ± 0.452) × 10-3°.
  10. Abdullah NN, Daud S, Al-Kubaisy W, Saari IS, Saad SR
    Eur J Obstet Gynecol Reprod Biol, 2016 Nov;206:136-140.
    PMID: 27693934 DOI: 10.1016/j.ejogrb.2016.09.011
    OBJECTIVES: The objectives of this study were to determine the prevalence and predictors of Pap smear screening among women aged 50 years and older.
    STUDY DESIGN: This cross-sectional study was conducted at two large urban health centres in Selangor. A total of 515 women aged 50 and older were recruited.
    RESULTS: The mean age of the respondents was 58.83±7.05, with a range of 50- 83 years. The prevalence of Pap smear screening was 39.22% (n=202). From the multivariate analysis, Pap smear screening was significantly associated with health care provider advice (adjusted odds ratio (AOR)=18.75; 95% CI=8.30, 42.37); tertiary (AOR=11.26; 95% CI=1.50, 84.68) and secondary education level (AOR=9.47; 95% CI=1.43, 62.84); use of contraception (AOR=2.90; 95% CI=1.48, 5.69); heart disease (AOR=0.22; 95% CI=0.05, 0.97); and worry about Pap smear results (AOR=0.20; 95% CI=0.09, 0.42).
    CONCLUSION: The prevalence of Pap smear screening in the older women is unsatisfactory. Health care provider advice, education level, use of contraception, heart disease and worry about Pap smear results were predictors of undergoing Pap smear screening in this study population.
    Study site: Two Klinik Kesihatan in Gombak, Selangor, Malaysia
  11. Majani AF, Ghazali SR, Yoke Yong C, Pauzi N, Adenan F, Manogaran K
    Psychol Rep, 2023 Aug;126(4):1605-1619.
    PMID: 35084251 DOI: 10.1177/00332941221075246
    Multiple exposures to life-threatening events may lead to various mental health issues and indirectly affect the marriage of those affected. Very few studies have investigated trauma exposure, posttraumatic stress disorder (PTSD), depressive symptoms, and marital conflicts among firefighters, a group that faces such exposure occupationally. The present study explores the relationship between trauma exposure, PTSD, and depression in relation to marital conflicts among firefighters in Sarawak, adopting a cross-sectional research design. Different marital status reported significant PTSD and depressive symptoms. The widowed scored higher PTSD and depressive symptoms than the married and single groups. Firefighters with PTSD and depressive symptoms reported having more problems in aggression family history of distress, sexual dissatisfaction, and problem solving communication than those without. Regression analysis showed that problem solving communication (t (212) = 2.59, p = .01) and global distress scores (t (212) = 2.17, p < .05) in type of marital conflicts served as a significant predictor for depressive symptoms. The present study suggests that proper planning for treatment and intervention is needed to improve psychological well-being among firefighters and other high-risk professions following multiple exposures to traumatic events in carrying their job duty. Proper intervention programs also should be initiated for spouses of firefighters dealing with traumatized partners.
  12. Mohamed NF, Ghazali SR, Yaacob NA, Rahim AAA, Maskon O
    Sultan Qaboos Univ Med J, 2018 Nov;18(4):e494-e500.
    PMID: 30988969 DOI: 10.18295/squmj.2018.18.04.011
    Objectives: Heart failure (HF) is a common clinical syndrome with an enormous impact on prognosis and lifestyle. Accordingly, rehabilitation measures need to be patient-specific and consider various sociocultural factors so as to improve the patient's quality of life (QOL). This study aimed to develop and validate a HF-specific QOL (HFQOL) questionnaire within a multicultural setting.

    Methods: This study took place at the National Heart Institute and Universiti Kebangsaan Malaysia Medical Centre, Kuala Lumpur, Malaysia, between March 2013 and March 2014. A self-administered 75-item HFQOL questionnaire was designed and administrated to 164 multi-ethnic Malaysian HF patients. Exploratory factor analysis was performed to assess the instrument's construct validity. Cronbach's alpha coefficients were used to determine internal consistency.

    Results: A total of 33 out of 75 items were retained in the final tool. The HFQOL questionnaire had three common factors-psychological, physical-social and spiritual wellbeing-resulting in a cumulative percentage of total variance of 44.3%. The factor loading ranges were 0.450-0.718 for psychological wellbeing (12 items), 0.394-0.740 for physical-social wellbeing (14 items) and 0.449-0.727 for spiritual wellbeing (seven items). The overall Cronbach's alpha coefficient of the questionnaire was 0.82, with coefficients of 0.86, 0.88 and 0.79 for the psychological, physical-social and spiritual wellbeing subdomains, respectively.

    Conclusion: The HFQOL questionnaire was found to be a valid and reliable measure of QOL among Malaysian HF patients from various ethnic groups. Such tools may facilitate cardiac care management planning among multi-ethnic patients with HF.

  13. Sekaran H, Gan CY, A Latiff A, Harvey TM, Mohd Nazri L, Hanapi NA, et al.
    Brain Res Bull, 2019 10;152:63-73.
    PMID: 31301381 DOI: 10.1016/j.brainresbull.2019.07.010
    Cerebral hypoperfusion involved a reduction in cerebral blood flow, leading to neuronal dysfunction, microglial activation and white matter degeneration. The effects on the blood-brain barrier (BBB) however, have not been well-documented. Here, two-vessel occlusion model was adopted to mimic the condition of cerebral hypoperfusion in Sprague-Dawley rats. The BBB permeability to high and low molecular weight exogenous tracers i.e. Evans blue dye and sodium fluorescein respectively, showed marked extravasation of the Evans blue dye in the frontal cortex, posterior cortex and thalamus-midbrain at day 1 following induction of cerebral hypoperfusion. Transmission electron microscopy revealed brain endothelial cell and astrocyte damages including increased pinocytotic vesicles and formation of membrane invaginations in the endothelial cells, and swelling of the astrocytes' end-feet. Investigation on brain microvessel protein expressions using two-dimensional (2D) gel electrophoresis coupled with LC-MS/MS showed that proteins involved in mitochondrial energy metabolism, transcription regulation, cytoskeleton maintenance and signaling pathways were differently expressed. The expression of aconitate hydratase, heterogeneous nuclear ribonucleoprotein, enoyl Co-A hydratase and beta-synuclein were downregulated, while the opposite observed for calreticulin and enhancer of rudimentary homolog. These findings provide insights into the BBB molecular responses to cerebral hypoperfusion, which may assist development of future therapeutic strategies.
  14. Abuelizz HA, Anouar EH, Marzouk M, Hasan MH, Saleh SR, Ahudhaif A, et al.
    Anticancer Agents Med Chem, 2020;20(14):1714-1721.
    PMID: 32593283 DOI: 10.2174/1871520620666200627212128
    BACKGROUND: The use of tyrosinase has confirmed to be the best means of recognizing safe, effective, and potent tyrosinase inhibitors for whitening skin. Twenty-four 2-phenoxy(thiomethyl)pyridotriazolopyrimidines were synthesized and characterized in our previous studies.

    OBJECTIVE: The present work aimed to evaluate their cytotoxicity against HepG2 (hepatocellular carcinoma), A549 (pulmonary adenocarcinoma), MCF-7 (breast adenocarcinoma) and WRL 68 (embryonic liver) cell lines.

    METHODS: MTT assay was employed to investigate the cytotoxicity, and a tyrosinase inhibitor screening kit was used to evaluate the Tyrosinase (TYR) inhibitory activity of the targets.

    RESULTS: The tested compounds exhibited no considerable cytotoxicity, and nine of them were selected for a tyrosinase inhibitory test. Compounds 2b, 2m, and 5a showed good inhibitory percentages against TYR compared to that of kojic acid (reference substance). Molecular docking was performed to rationalize the Structure-Activity Relationship (SAR) of the target pyridotriazolopyrimidines and analyze the binding between the docked-selected compounds and the amino acid residues in the active site of tyrosinase.

    CONCLUSION: The target pyridotriazolopyrimidines were identified as a new class of tyrosinase inhibitors.

  15. Che Mohd Nassir CMN, Damodaran T, Yusof SR, Norazit A, Chilla G, Huen I, et al.
    Pharmaceutics, 2021 Aug 05;13(8).
    PMID: 34452169 DOI: 10.3390/pharmaceutics13081207
    The distinctive anatomical assemble and functionally discrete multicellular cerebrovasculature dynamics confer varying rheological and blood-brain barrier permeabilities to preserve the integrity of cerebral white matter and its neural microenvironment. This homeostasis intricately involves the glymphatic system that manages the flow of interstitial solutes, metabolic waste, and clearance through the venous circulation. As a physiologically integrated neurogliovascular unit (NGVU) serving a particularly vulnerable cerebral white matter (from hypoxia, metabolic insults, infection, and inflammation), a likely insidious process over a lifetime could inflict microenvironment damages that may lead to pathological conditions. Two such conditions, cerebral small vessel disease (CSVD) and vascular parkinsonism (VaP), with poorly understood pathomechanisms, are frequently linked to this brain-wide NGVU. VaP is widely regarded as an atypical parkinsonism, described by cardinal motor manifestations and the presence of cerebrovascular disease, particularly white matter hyperintensities (WMHs) in the basal ganglia and subcortical region. WMHs, in turn, are a recognised imaging spectrum of CSVD manifestations, and in relation to disrupted NGVU, also include enlarged perivascular spaces. Here, in this narrative review, we present and discuss on recent findings that argue for plausible clues between CSVD and VaP by focusing on aberrant multicellular dynamics of a unique integrated NGVU-a crossroad of the immune-vascular-nervous system-which may also extend fresher insights into the elusive interplay between cerebral microvasculature and neurodegeneration, and the potential therapeutic targets.
  16. Yusof SR, Mohd Uzid M, Teh EH, Hanapi NA, Mohideen M, Mohamad Arshad AS, et al.
    Addict Biol, 2019 09;24(5):935-945.
    PMID: 30088322 DOI: 10.1111/adb.12661
    Mitragyna speciosa is reported to be beneficial for the management of chronic pain and opioid withdrawal in the evolving opioid epidemic. Data on the blood-brain barrier (BBB) transport of mitragynine and 7-hydroxymitragynine, the active compounds of the plant, are still lacking and inconclusive. Here, we present for the first time the rate and the extent of mitragynine and 7-hydroxymitragynine transport across the BBB, with an investigation of their post-BBB intra-brain distribution. We utilized an in vitro BBB model to study the rate of BBB permeation of the compounds and their interaction with efflux transporter P-glycoprotein (P-gp). Mitragynine showed higher apical-to-basolateral (A-B, i.e. blood-to-brain side) permeability than 7-hydroxymitragynine. 7-Hydroxymitragynine showed a tendency to efflux, with efflux ratio (B-A/A-B) of 1.39. Both were found to inhibit the P-gp and are also subject to efflux by the P-gp. Assessment of the extent of BBB transport in vivo in rats from unbound brain to plasma concentration ratios (Kp,uu,brain ) revealed extensive efflux of both compounds, with less than 10 percent of unbound mitragynine and 7-hydroxymitragynine in plasma crossing the BBB. By contrast, the extent of intra-brain distribution was significantly different, with mitragynine having 18-fold higher brain tissue uptake in brain slice assay compared with 7-hydroxymitragynine. Mitragynine showed a moderate capacity to accumulate inside brain parenchymal cells, while 7-hydroxymitragynine showed restricted cellular barrier transport. The presented findings from this systematic investigation of brain pharmacokinetics of mitragynine and 7-hydroxymitragynine are essential for design and interpretation of in vivo experiments aiming to establish exposure-response relationship.
  17. Nielsen SSE, Siupka P, Georgian A, Preston JE, Tóth AE, Yusof SR, et al.
    J Vis Exp, 2017 09 24.
    PMID: 28994773 DOI: 10.3791/56277
    The aim of this protocol presents an optimized procedure for the purification and cultivation of pBECs and to establish in vitro blood-brain barrier (BBB) models based on pBECs in mono-culture (MC), MC with astrocyte-conditioned medium (ACM), and non-contact co-culture (NCC) with astrocytes of porcine or rat origin. pBECs were isolated and cultured from fragments of capillaries from the brain cortices of domestic pigs 5-6 months old. These fragments were purified by careful removal of meninges, isolation and homogenization of grey matter, filtration, enzymatic digestion, and centrifugation. To further eliminate contaminating cells, the capillary fragments were cultured with puromycin-containing medium. When 60-95% confluent, pBECs growing from the capillary fragments were passaged to permeable membrane filter inserts and established in the models. To increase barrier tightness and BBB characteristic phenotype of pBECs, the cells were treated with the following differentiation factors: membrane permeant 8-CPT-cAMP (here abbreviated cAMP), hydrocortisone, and a phosphodiesterase inhibitor, RO-20-1724 (RO). The procedure was carried out over a period of 9-11 days, and when establishing the NCC model, the astrocytes were cultured 2-8 weeks in advance. Adherence to the described procedures in the protocol has allowed the establishment of endothelial layers with highly restricted paracellular permeability, with the NCC model showing an average transendothelial electrical resistance (TEER) of 1249 ± 80 Ω cm2, and paracellular permeability (Papp) for Lucifer Yellow of 0.90 10-6 ± 0.13 10-6 cm sec-1 (mean ± SEM, n=55). Further evaluation of this pBEC phenotype showed good expression of the tight junctional proteins claudin 5, ZO-1, occludin and adherens junction protein p120 catenin. The model presented can be used for a range of studies of the BBB in health and disease and, with the highly restrictive paracellular permeability, this model is suitable for studies of transport and intracellular trafficking.
  18. Tee HK, Tan CW, Yogarajah T, Lee MHP, Chai HJ, Hanapi NA, et al.
    PLoS Pathog, 2019 11;15(11):e1007863.
    PMID: 31730673 DOI: 10.1371/journal.ppat.1007863
    Enterovirus A71 (EV-A71) causes hand, foot and mouth disease epidemics with neurological complications and fatalities. However, the neuropathogenesis of EV-A71 remains poorly understood. In mice, adaptation and virulence determinants have been mapped to mutations at VP2-149, VP1-145 and VP1-244. We investigate how these amino acids alter heparin-binding phenotype and shapes EV-A71 virulence in one-day old mice. We constructed six viruses with varying residues at VP1-98, VP1-145 (which are both heparin-binding determinants) and VP2-149 (based on the wild type 149K/98E/145Q, termed KEQ) to generate KKQ, KKE, KEE, IEE and IEQ variants. We demonstrated that the weak heparin-binder IEE was highly lethal in mice. The initially strong heparin-binding IEQ variant acquired an additional mutation VP1-K244E, which confers weak heparin-binding phenotype resulting in elevated viremia and increased virus antigens in mice brain, with subsequent high virulence. IEE and IEQ-244E variants inoculated into mice disseminated efficiently and displayed high viremia. Increasing polymerase fidelity and impairing recombination of IEQ attenuated the virulence, suggesting the importance of population diversity in EV-A71 pathogenesis in vivo. Combining in silico docking and deep sequencing approaches, we inferred that virus population diversity is shaped by electrostatic interactions at the five-fold axis of the virus surface. Electrostatic surface charges facilitate virus adaptation by generating poor heparin-binding variants for better in vivo dissemination in mice, likely due to reduced adsorption to heparin-rich peripheral tissues, which ultimately results in increased neurovirulence. The dynamic switching between heparin-binding and weak heparin-binding phenotype in vivo explained the neurovirulence of EV-A71.
  19. Chirawat P, Kamolthip R, Rattaprach R, Nadhiroh SR, Tung SEH, Gan WY, et al.
    Int J Environ Res Public Health, 2022 Nov 29;19(23).
    PMID: 36497942 DOI: 10.3390/ijerph192315868
    The previous studies found that the Weight Self Stigma Questionnaire (WSSQ) and Perceived Weight Stigma Scale (PWSS) have shown well-established psychometric properties for measuring weight stigma with strong reliability and validity from different languages. However, there is a lack of an appropriate instrument in assessing weight stigma in Thai samples. This study aimed to examine the Thai WSSQ and PWSS among Thai university students. Both instruments were also assessed for their measurement invariance across gender and weight status subgroups. A cross-sectional study was conducted on 801 university students in Thailand between January 2022 and July 2022. All participants completed a demographic questionnaire and a Thai version of the WSSQ, PWSS, and Depression Anxiety Stress Scale-21 (DASS-21) via an online survey. Reliability, validity, measurement invariance, and correlational analyses were performed to investigate whether the Thai versions of the WSSQ and PWSS psychometric properties were acceptable. Both translated questionnaires demonstrated overall acceptable psychometric properties and revealed a two-dimensional structure for the WSSQ, and unidimensional structure for the PWSS. Measurement invariance was obtained across gender and weight status subgroups. Additionally, both translated WSSQ and PWSS were significantly correlated with DASS-21. The Thai-translated WSSQ and PWSS showed strong validity, reliability, and factorial invariance across different subgroups for measuring weight stigma among Thai university students.
  20. Pramukti I, Nurmala I, Nadhiroh SR, Tung SEH, Gan WY, Siaw YL, et al.
    Psychiatry Investig, 2023 Dec;20(12):1103-1111.
    PMID: 38163649 DOI: 10.30773/pi.2022.0304
    OBJECTIVE: Social media addiction and internet gaming disorder may cause mental health problems among a minority of university students. The Bergen Social Media Addiction Scale (BSMAS) and the 9-item Internet Gaming Disorder Scale-Short Form (IGDS9-SF) are commonly used worldwide. However, they have not been translated or validated into Indonesian. The present study aimed to translate and validate the BSMAS and IGDS9-SF in an Indonesian context among young adults.

    METHODS: A multi-center, web-based cross-sectional study was conducted among 458 university students (74% female; mean age 22.5 years) in Indonesia from June to December 2021. The BSMAS and IGDS9-SF were translated into Indonesian. Internal consistency (using Cronbach's α and McDonald's ω) and factor structure (using confirmatory factor analysis) of the two instruments were examined. Concurrent validity of BSMAS and IGDS9-SF was examined using their correlations with two external concepts: nomophobia and psychological distress.

    RESULTS: Internal consistency of the Indonesian BSMAS and IGDS9-SF were both acceptable (Cronbach's α=0.80 and 0.90; McDonald's ω=0.86 and 0.92). Both instruments were unidimensional with good factor loadings (0.54-0.78 for BSMAS; 0.63-0.79 for IGDS9-SF). Moreover, BSMAS and IGDS9-SF had stronger associations with nomophobia (r=0.58 and 0.12; p<0.001) than with psychological distress (r=0.43 and 0.15; p<0.001).

    CONCLUSION: The Indonesian versions of the BSMAS and IGDS9-SF had good psychometric properties in terms of linguistic validity, unidimensionality, and reliability. The findings indicate the tools are appropriate for assessing the risk of social media addiction and internet gaming disorder among university students in Indonesia.

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