Displaying publications 81 - 100 of 203 in total

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  1. Entero-and myxoviral infections of the central nervous system
    Tan DS
    Med J Malaya, 1968 Dec;23(2):140-5.
    PMID: 4308419
    Matched MeSH terms: Central Nervous System Diseases/etiology*
  2. Effects of Kratom (Mitragyna Speciosa Korth.) Use in Regular Users
    Singh D, Narayanan S, Grundmann O, Dzulkapli EB, Vicknasingam B
    Subst Use Misuse, 2019;54(14):2284-2289.
    PMID: 31347441 DOI: 10.1080/10826084.2019.1645178
    Background: Mitragyna speciosa (Korth.) or kratom is an indigenous medicinal plant of Southeast Asia. Kratom is widely reported to have dose-dependent effects based on available literature, but to our knowledge, this has not been established conclusively. Objective: This study sought to evaluate if kratom use produces dose-dependent effects, with a stimulant effect at low doses and a sedative effect at high doses, in a sample of regular kratom users. Methods: A total of 63 regular kratom users participated in this cross-sectional study. The Brief-Biphasic Alcohol Effects Scale (B-BAES) was used to determine subjects self-report kratom use experiences. Results: Almost all in the sample were male (98%, n = 62/63), and the majority of subjects were Malays (94%, n = 59/63). The mean age of the subjects in the sample was 43.8 years (SD = 12.1). Seventy-five percent (n = 47/63) have >5 years kratom use history, and 65% (n = 41/63) consumed >3 glasses of kratom daily. Results from first test showed no significant difference in the stimulant (t61 =0.371, p 3 glasses a day or less than this amount, regardless of duration of use. In the second test, no significant differences in the mean scores were found among those who consumed >3 glasses daily or less than this amount among short-term or long-term uses. Conclusions: Daily kratom use produced both stimulant and sedative effects but they were not statistically significantly associated with the dose consumed, both among short-term and long-term users in our sample.
    Matched MeSH terms: Central Nervous System Stimulants/administration & dosage*
  3. Coxsackievirus A16 in a 1-Day-Old Mouse Model of Central Nervous System Infection Shows Lower Neurovirulence than Enterovirus A71
    Hooi YT, Ong KC, Tan SH, Perera D, Wong KT
    J Comp Pathol, 2020 Apr;176:19-32.
    PMID: 32359633 DOI: 10.1016/j.jcpa.2020.02.001
    Coxsackievirus A16 (CV-A16) and enterovirus A71 (EV-A71) are the major causes of hand, foot and mouth disease in young children. Although less so with CV-A16, both viruses are associated with serious neurological syndromes, but the differences between their central nervous system infections remain unclear. We conducted a comparative infection study using clinically-isolated CV-A16 and EV-A71 strains in a 1-day-old mouse model to better understand the neuropathology and neurovirulence of the viruses. New serotype-specific probes for in situ hybridization were developed and validated to detect CV-A16 and EV-A71 RNA in infected tissues. Demonstration of CV-A16 virus antigens/RNA, mainly in the brainstem and spinal cord neurons, confirmed neurovirulence, but showed lower densities than in EV-A71 infected animals. A higher lethal dose50 for CV-A16 suggested that CV-A16 is less neurovirulent. Focal virus antigens/RNA in the anterior horn white matter and adjacent efferent motor nerves suggested that neuroinvasion is possibly via retrograde axonal transport in peripheral motor nerves.
    Matched MeSH terms: Central Nervous System Infections/virology*
  4. Fulltext Evaluation of difference in the neurotoxicity produced by dermal application of chlorpyrifos on the neonatal and adult mice
    Mitra NK, Lee MS, Nadarajah VD
    Trop Biomed, 2010 Apr;27(1):19-29.
    PMID: 20562809
    Dermal exposure to organophosphate pesticide is important because of its popular use. This study planned to compare the changes in serum acetylcholinesterase, paraoxonase and neuronal density of hippocampus and iso-cortex between two age groups of Swiss albino mice (18-day-old and 150-day-old) after dermal application of (1/2) LD50 of chlorpyrifos for 14 days. Statistically significant reduction was observed in serum acetylcholinesterase (Mann-Whitney test, p<0.05) and neuronal density (Independent samples t-test, p<0.05) in exposed groups compared to the control. The reduction in serum AChE and neuronal density was more pronounced in exposed adult mice than in exposed neonatal mice. The paraoxonase level was insignificant in control neonatal mice, whereas it was 890-fold more in exposed neonatal mice. Upregulated paraoxonase levels may be extrapolated to produce relatively lower reduction of cholinesterase and neuronal density in neonatal mice.
    Matched MeSH terms: Central Nervous System Diseases/chemically induced*
  5. Epilepsy in the tropics: Emerging etiologies
    Carrizosa Moog J, Kakooza-Mwesige A, Tan CT
    Seizure, 2017 Jan;44:108-112.
    PMID: 27986419 DOI: 10.1016/j.seizure.2016.11.032
    Epilepsy is considered by the World Health Organization a public health priority with more than 50 million human beings affected by the disease. More than 80% of persons with epilepsy live in low and middle income countries and most of them in tropical areas. Several emerging, re-emerging and neglected diseases are symptomatic etiologies that jointly contribute to the enormous global burden of epilepsy. Besides the clinical strengths to reduce diagnostic and treatment gaps, other strategies in social, economic, cultural, educational and health policies are needed to prevent and treat appropriately vulnerable and affected persons with epilepsy. From the public health point of view, several of those strategies could be more effective in reducing the incidence and burden of the disease than the clinical approach of diagnosis and treatment. Special attention has to be given to stigma reduction and promotion of human rights. Several aspects mentioned in this abstract slip away the scope of the article, but it is a remainder to approach epilepsy in an inter- and transdisciplinary manner, an integral and pertinent approach needed and requested in tropical counties. The article focuses only on emergent and re-emergent etiologies of epilepsy in the tropics like malaria, HIV, neurocysticercosis, viral encephalitis and traumatic brain injury.
    Matched MeSH terms: Central Nervous System Infections/complications*
  6. Coma and consciousness
    Black W, Arumugasamy N
    Med J Malaya, 1971 Jun;25(4):241-9.
    PMID: 4261293
    Matched MeSH terms: Central Nervous System Diseases/complications
  7. Fulltext Early Initiation of Amphetamine-Type Stimulants (ATS) Use Associated with Lowered Cognitive Performance among Individuals with Co-Occurring Opioid and ATS Use Disorders in Malaysia
    Chooi WT, Mohd Zaharim N, Desrosiers A, Ahmad I, Yasin MAM, Syed Jaapar SZ, et al.
    J Psychoactive Drugs, 2017 06 29;49(4):326-332.
    PMID: 28661714 DOI: 10.1080/02791072.2017.1342152
    Amphetamine-type stimulants (ATS) use is increasingly prevalent in Malaysia, including among individuals who also use opioids. We evaluated cognitive functioning profiles among individuals with co-occurring opioid and ATS dependence and their lifetime patterns of drug use. Participants (N = 50) enrolling in a clinical trial of buprenorphine/naloxone treatment with or without atomoxetine completed the Raven's Standard Progressive Matrices, Rey-Osterrieth Complex Figure Test, Digit Span, Trail Making and Symbol Digit Substitution tasks. Multidimensional scaling and a K-means cluster analyses were conducted to classify participants into lower versus higher cognitive performance groups. Subsequently, analyses of variance procedures were conducted to evaluate between group differences on drug use history and demographics. Two clusters of individuals with distinct profiles of cognitive performance were identified. The age of ATS use initiation, controlling for the overall duration of drug use, was significantly earlier in the lower than in the higher cognitive performance cluster: 20.9 (95% CI: 18.0-23.8) versus 25.2 (95% CI: 22.4-28.0, p = 0.038). While adverse effects of ATS use on cognitive functioning can be particularly pronounced with younger age, potentially related to greater vulnerability of the developing brain to stimulant and/or neurotoxic effects of these drugs, the current study findings cannot preclude lowered cognitive performance before initiation of ATS use.
    Matched MeSH terms: Central Nervous System Stimulants/adverse effects*
  8. Aryl Quinazolinone Derivatives as Novel Therapeutic Agents against Brain-Eating Amoebae
    Mungroo MR, Shahbaz MS, Anwar A, Saad SM, Khan KM, Khan NA, et al.
    ACS Chem Neurosci, 2020 08 19;11(16):2438-2449.
    PMID: 31961126 DOI: 10.1021/acschemneuro.9b00596
    Naegleria fowleri and Balamuthia mandrillaris are protist pathogens that infect the central nervous system, causing primary amoebic meningoencephalitis and granulomatous amoebic encephalitis with mortality rates of over 95%. Quinazolinones and their derivatives possess a wide spectrum of biological properties, but their antiamoebic effects against brain-eating amoebae have never been tested before. In this study, we synthesized a variety of 34 novel arylquinazolinones derivatives (Q1-Q34) by altering both quinazolinone core and aryl substituents. To study the antiamoebic activity of these synthetic arylquinazolinones, amoebicidal and amoebistatic assays were performed against N. fowleri and B. mandrillaris. Moreover, amoebae-mediated host cells cytotopathogenicity and cytotoxicity assays were performed against human keratinocytes cells in vitro. The results revealed that selected arylquinazolinones derivatives decreased the viability of B. mandrillaris and N. fowleri significantly (P < 0.05) and reduced cytopathogenicity of both parasites. Furthermore, these compounds were also found to be least cytotoxic against HaCat cells. Considering that nanoparticle-based materials possess potent in vitro activity against brain-eating amoebae, we conjugated quinazolinones derivatives with silver nanoparticles and showed that activities of the drugs were enhanced successfully after conjugation. The current study suggests that quinazolinones alone as well as conjugated with silver nanoparticles may serve as potent therapeutics against brain-eating amoebae.
    Matched MeSH terms: Central Nervous System Parasitic Infections; Central Nervous System Protozoal Infections
  9. Fulltext Tuberculous meningitis is a major cause of mortality and morbidity in adults with central nervous system infections in Kota Kinabalu, Sabah, Malaysia: an observational study
    Lee HG, William T, Menon J, Ralph AP, Ooi EE, Hou Y, et al.
    BMC Infect Dis, 2016 06 16;16:296.
    PMID: 27306100 DOI: 10.1186/s12879-016-1640-x
    BACKGROUND: Central nervous system (CNS) infections are a significant contributor to morbidity and mortality globally. However, most published studies have been conducted in developed countries where the epidemiology and aetiology differ significantly from less developed areas. Additionally, there may be regional differences due to variation in the socio-economic levels, public health services and vaccination policies. Currently, no prospective studies have been conducted in Sabah, East Malaysia to define the epidemiology and aetiology of CNS infections. A better understanding of these is essential for the development of local guidelines for diagnosis and management.

    METHODS: We conducted a prospective observational cohort study in patients aged 12 years and older with suspected central nervous system infections at Queen Elizabeth Hospital, Kota Kinabalu, Sabah, Malaysia between February 2012 and March 2013. Cerebrospinal fluid was sent for microscopy, biochemistry, bacterial and mycobacterial cultures, Mycobacterium tuberculosis polymerase chain reaction (PCR), and multiplex and MassCode PCR for various viral and bacterial pathogens.

    RESULTS: A total of 84 patients with clinically suspected meningitis and encephalitis were enrolled. An aetiological agent was confirmed in 37/84 (44 %) of the patients. The most common diagnoses were tuberculous meningitis (TBM) (41/84, 48.8 %) and cryptococcal meningoencephalitis (14/84, 16.6 %). Mycobacterium tuberculosis was confirmed in 13/41 (31.7 %) clinically diagnosed TBM patients by cerebrospinal fluid PCR or culture. The acute case fatality rate during hospital admission was 16/84 (19 %) in all patients, 4/43 (9 %) in non-TBM, and 12/41 (29 %) in TBM patients respectively (p = 0.02).

    CONCLUSION: TBM is the most common cause of CNS infection in patients aged 12 years or older in Kota Kinabalu, Sabah, Malaysia and is associated with high mortality and morbidity. Further studies are required to improve the management and outcome of TBM.

    Matched MeSH terms: Central Nervous System Infections/cerebrospinal fluid; Central Nervous System Infections/microbiology; Central Nervous System Infections/mortality; Central Nervous System Infections/epidemiology
  10. Fulltext Multi-assay investigation of viral etiology in pediatric central nervous system infections
    Altay-Kocak A, Bozdayi G, Michel J, Polat M, Kanik-Yuksek S, Tezer H, et al.
    J Infect Dev Ctries, 2020 06 30;14(6):572-579.
    PMID: 32683347 DOI: 10.3855/jidc.12327
    INTRODUCTION: In an attempt to identify a wide spectrum of viral infections, cerebrospinal fluid (CSF) specimens were collected from pediatric cases with the preliminary diagnosis of viral encephalitis/meningoencephalitis in two reference hospitals, from October 2011 to December 2015.

    METHODOLOGY: A combination of nucleic acid-based assays, including in house generic polymerase chain reaction (PCR) assays for enteroviruses, flaviviruses and phleboviruses, a commercial real-time PCR assay for herpesviruses and a commercial real time multiplex PCR, enabling detection of frequently-observed viral, bacterial and fungal agents were employed for screening.

    RESULTS: The microbial agent could be characterized in 10 (10%) of the 100 specimens. Viral etiology could be demonstrated in 7 (70%) specimens, which comprises Human Herpesvirus 6 (4/7), Herpes Simplex virus type1 (2/7) and Enteroviruses (1/7). In 3 specimens (30%), Streptococcus pneumoniae, Listeria monocytogenes and Staphylococcus aureus were detected via the multiplex PCR, which were also isolated in bacteriological media. All specimens with detectable viral nucleic acids, as well as unreactive specimens via nucleic acid testing remained negative in bacteriological cultures.

    CONCLUSIONS: Herpes and enteroviruses were identified as the primary causative agents of central nervous system infections in children. Enterovirus testing must be included in the diagnostic work-up of relevant cases.

    Matched MeSH terms: Central Nervous System Infections/cerebrospinal fluid; Central Nervous System Infections/diagnosis; Central Nervous System Infections/etiology*; Central Nervous System Infections/virology*
  11. Effects of asiatic acid on passive and active avoidance task in male Spraque-Dawley rats
    Nasir MN, Habsah M, Zamzuri I, Rammes G, Hasnan J, Abdullah J
    J Ethnopharmacol, 2011 Mar 24;134(2):203-9.
    PMID: 21167268 DOI: 10.1016/j.jep.2010.12.010
    Centella asiatica has a reputation to restore declining cognitive function in traditional medicine. To date, only a few compounds that show enhancing learning and memory properties are available. Therefore, the present study investigates the effects of for acute administration of asiatic acid (A-A) isolated from Centella asiatica administration on memory and learning in male Spraque-Dawley rats.
    Matched MeSH terms: Central Nervous System Agents/isolation & purification; Central Nervous System Agents/pharmacology*
  12. The rise of methamphetamine in Southeast and East Asia
    McKetin R, Kozel N, Douglas J, Ali R, Vicknasingam B, Lund J, et al.
    Drug Alcohol Rev, 2008 May;27(3):220-8.
    PMID: 18368602 DOI: 10.1080/09595230801923710
    Southeast and East Asia has become a global hub for methamphetamine production and trafficking over the past decade. This paper describes the rise of methamphetamine supply and to what extent use of the drug is occurring in the region.
    Matched MeSH terms: Central Nervous System Stimulants/adverse effects; Central Nervous System Stimulants/supply & distribution*
  13. Removal of caffeine from aqueous solution by indirect electrochemical oxidation using a graphite-PVC composite electrode: A role of hypochlorite ion as an oxidising agent
    Al-Qaim FF, Mussa ZH, Othman MR, Abdullah MP
    J Hazard Mater, 2015 Dec 30;300:387-397.
    PMID: 26218306 DOI: 10.1016/j.jhazmat.2015.07.007
    The electrochemical oxidation of caffeine, a widely over-the-counter stimulant drug, has been investigated in effluent wastewater and deionized water (DIW) using graphite-poly vinyl chloride (PVC) composite electrode as anode. Effects of initial concentration of caffeine, chloride ion (Cl(-)) loading, presence of hydrogen peroxide (H2O2), sample volume, type of sample and applied voltage were determined to test and to validate a kinetic model for the oxidation of caffeine by the electrochemical oxidation process. The results revealed that the electrochemical oxidation rates of caffeine followed pseudo first-order kinetics, with rate constant values ranged from 0.006 to 0.23 min(-1) depending on the operating parameters. The removal efficiency of caffeine increases with applied voltage very significantly, suggesting a very important role of mediated oxidation process. However, the consumption energy was considered during electrochemical oxidation process. In chloride media, removal of caffeine is faster and more efficiently, although occurrence of more intermediates takes place. The study found that the adding H2O2 to the NaCl solution will inhibit slightly the electrochemical oxidation rate in comparison with only NaCl in solution. Liquid chromatography-time of flight-mass spectrometry (LC-TOF-MS) technique was applied to the identification of the by-products generated during electrochemical oxidation, which allowed to construct the proposed structure of by-products.
    Matched MeSH terms: Central Nervous System Stimulants/isolation & purification*; Central Nervous System Stimulants/toxicity
  14. Parasitic worms of the central nervous system: an Australian perspective
    Hughes AJ, Biggs BA
    Intern Med J, 2002 Nov;32(11):541-53.
    PMID: 12412938
    The diagnosis and management of parasitic diseases of the central nervous system (CNS) is difficult, even for infectious diseases physicians and neurologists. Furthermore, few overviews of the spectrum of causative helminths and clinical syndromes have been published. In the present study, we review the seven most common parasitic diseases of the CNS: (i) cysticercosis, (ii) neuroschistosomiasis, (iii) paragonimiasis, (iv) angiostrongyliasis, (v) hydatid disease, (vi) sparganosis and (vii) gnathostomiasis. Major syndromes of parasitic disease of the CNS and their differential causes are discussed, including: (i) cystic lesions, (ii) enhancing granulomas (with and without creeping subcutaneous eruptions), (iii) eosinophilic meningoencephalitis and (iv) spinal cord disease. Specific risk factors that predispose to these infections are also discussed and particular attention is drawn to the situation in Australia.
    Matched MeSH terms: Central Nervous System Parasitic Infections/diagnosis*; Central Nervous System Parasitic Infections/therapy*
  15. The Use of Methylphenidate for Physical and Psychological Symptoms in Cancer Patients: A Review
    Andrew BN, Guan NC, Jaafar NRN
    Curr Drug Targets, 2018;19(8):877-887.
    PMID: 28322161 DOI: 10.2174/1389450118666170317162603
    BACKGROUND: One of the goals of cancer treatment is symptoms management especially at the end stage. The common symptoms in cancer include pain, fatigue, depression and cognitive dysfunction. The available treatment options for symptom management are limited. Methylphenidate, a psychostimulant, may be of benefit for these patients. In this report, we review the use of methylphenidate for symptoms control in cancer patients.

    METHOD: Electronic literature search on PubMed was conducted using the following keywords: methylphenidate, cancer, carcinoma, oncology, oncological and tumour. We identified forty two relevant studies and publications on the use of methylphenidate in cancer patients to be included in this review.

    RESULTS: Methylphenidate was found to have some evidence in reducing opioid-induced sedation, improving cognitive symptoms and reduction of fatigue in cancer patients. Nevertheless, the results were inconsistent due to variations in the study populations, study design and outcome measures, among others. There was minimal evidence on its use in treating depression. Otherwise, methylphenidate was generally well-tolerated by patients.

    CONCLUSION: This review potentially supports the use of methylphenidate for opioid-induced sedation, cognitive decline and fatigue in cancer patients. Further placebo-controlled trials would help in strengthening the evidence for this treatment.

    Matched MeSH terms: Central Nervous System Stimulants/adverse effects; Central Nervous System Stimulants/therapeutic use*
  16. Anterior spinal cord syndrome as a rare complication of acute bacterial meningitis in an adult
    Ng KS, Abdul Halim S
    BMJ Case Rep, 2018 Oct 24;2018.
    PMID: 30361450 DOI: 10.1136/bcr-2018-226082
    Acute bacterial meningitis is not an uncommon central nervous system infection. In severe cases, it can be associated with various neurological or systemic complications. However, acute spinal cord dysfunction rarely occurs. We report a case of bacterial meningitis complicated with spinal cord infarction despite adequate treatment with antibiotics and corticosteroid therapy. He had residual paraplegia and was fully dependent in the activity of daily living.
    Matched MeSH terms: Central Nervous System Bacterial Infections/diagnosis*; Central Nervous System Bacterial Infections/drug therapy
  17. Japanese Encephalitis Virus Infects the Thalamus Early Followed by Sensory-Associated Cortex and Other Parts of the Central and Peripheral Nervous Systems
    Fu TL, Ong KC, Tan SH, Wong KT
    J. Neuropathol. Exp. Neurol., 2019 12 01;78(12):1160-1170.
    PMID: 31675093 DOI: 10.1093/jnen/nlz103
    Japanese encephalitis (JE) is a known CNS viral infection that often involves the thalamus early. To investigate the possible role of sensory peripheral nervous system (PNS) in early neuroinvasion, we developed a left hindlimb footpad-inoculation mouse model to recapitulate human infection by a mosquito bite. A 1-5 days postinfection (dpi) study, demonstrated focal viral antigens/RNA in contralateral thalamic neurons at 3 dpi in 50% of the animals. From 4 to 5 dpi, gradual increase in viral antigens/RNA was observed in bilateral thalami, somatosensory, and piriform cortices, and then the entire CNS. Infection of neuronal bodies and adjacent nerves in dorsal root ganglia (DRGs), trigeminal ganglia, and autonomic ganglia (intestine, etc.) was also observed from 5 dpi. Infection of explant organotypic whole brain slice cultures demonstrated no viral predilection for the thalamus, while DRG and intestinal ganglia organotypic cultures confirmed sensory and autonomic ganglia susceptibility to infection, respectively. Early thalamus and sensory-associated cortex involvement suggest an important role for sensory pathways in neuroinvasion. Our results suggest that JE virus neuronotropism is much more extensive than previously known, and that the sensory PNS and autonomic system are susceptible to infection.
    Matched MeSH terms: Central Nervous System Infections/pathology; Central Nervous System Infections/virology
  18. Fulltext In Silico and In Vitro Analysis of Bacoside A Aglycones and Its Derivatives as the Constituents Responsible for the Cognitive Effects of Bacopa monnieri
    Ramasamy S, Chin SP, Sukumaran SD, Buckle MJ, Kiew LV, Chung LY
    PLoS One, 2015;10(5):e0126565.
    PMID: 25965066 DOI: 10.1371/journal.pone.0126565
    Bacopa monnieri has been used in Ayurvedic medicine to improve memory and cognition. The active constituent responsible for its pharmacological effects is bacoside A, a mixture of dammarane-type triterpenoid saponins containing sugar chains linked to a steroid aglycone skeleton. Triterpenoid saponins have been reported to be transformed in vivo to metabolites that give better biological activity and pharmacokinetic characteristics. Thus, the activities of the parent compounds (bacosides), aglycones (jujubogenin and pseudojujubogenin) and their derivatives (ebelin lactone and bacogenin A1) were compared using a combination of in silico and in vitro screening methods. The compounds were docked into 5-HT1A, 5-HT2A, D1, D2, M1 receptors and acetylcholinesterase (AChE) using AutoDock and their central nervous system (CNS) drug-like properties were determined using Discovery Studio molecular properties and ADMET descriptors. The compounds were screened in vitro using radioligand receptor binding and AChE inhibition assays. In silico studies showed that the parent bacosides were not able to dock into the chosen CNS targets and had poor molecular properties as a CNS drug. In contrast, the aglycones and their derivatives showed better binding affinity and good CNS drug-like properties, were well absorbed through the intestines and had good blood brain barrier (BBB) penetration. Among the compounds tested in vitro, ebelin lactone showed binding affinity towards M1 (Ki = 0.45 μM) and 5-HT2A (4.21 μM) receptors. Bacoside A and bacopaside X (9.06 μM) showed binding affinity towards the D1 receptor. None of the compounds showed any inhibitory activity against AChE. Since the stimulation of M1 and 5-HT2A receptors has been implicated in memory and cognition and ebelin lactone was shown to have the strongest binding energy, highest BBB penetration and binding affinity towards M1 and 5-HT2A receptors, we suggest that B. monnieri constituents may be transformed in vivo to the active form before exerting their pharmacological activity.
    Matched MeSH terms: Central Nervous System/drug effects; Central Nervous System/chemistry
  19. Dexamphetamine increased speech and visual unimodal illusions in healthy participants without affecting temporal binding window
    Voon FL, Loffman SJ, Lim MJH, Lee JWY, Iyyalol R, Martin-Iverson MT
    Hum Psychopharmacol, 2024 May;39(3):e2896.
    PMID: 38353526 DOI: 10.1002/hup.2896
    OBJECTIVE: Stimuli received beyond a very short timeframe, known as temporal binding windows (TBWs), are perceived as separate events. In previous audio-visual multisensory integration (McGurk effect) studies, widening of TBWs has been observed in people with schizophrenia. The present study aimed to determine if dexamphetamine could increase TBWs in unimodal auditory and unimodal visual illusions that may have some validity as experimental models for auditory and visual hallucinations in psychotic disorders.

    METHODS: A double-blind, placebo-controlled, counter-balanced crossover design with permuted block randomisation for drug order was followed. Dexamphetamine (0.45 mg/kg, PO, q.d.) was administered to healthy participants. Phantom word illusion (speech illusion) and visual-induced flash illusion/VIFI (visual illusion) tests were measured to determine if TBWs were altered as a function of delay between stimuli presentations. Word emotional content for phantom word illusions was also analysed.

    RESULTS: Dexamphetamine significantly increased the total number of phantom words/speech illusions (p 

    Matched MeSH terms: Central Nervous System Stimulants/administration & dosage; Central Nervous System Stimulants/pharmacology
  20. Fulltext Following "the Roots" of Kratom (Mitragyna speciosa): The Evolution of an Enhancer from a Traditional Use to Increase Work and Productivity in Southeast Asia to a Recreational Psychoactive Drug in Western Countries
    Cinosi E, Martinotti G, Simonato P, Singh D, Demetrovics Z, Roman-Urrestarazu A, et al.
    Biomed Res Int, 2015;2015:968786.
    PMID: 26640804 DOI: 10.1155/2015/968786
    The use of substances to enhance human abilities is a constant and cross-cultural feature in the evolution of humanity. Although much has changed over time, the availability on the Internet, often supported by misleading marketing strategies, has made their use even more likely and risky. This paper will explore the case of Mitragyna speciosa Korth. (kratom), a tropical tree used traditionally to combat fatigue and improve work productivity among farm populations in Southeast Asia, which has recently become popular as novel psychoactive substance in Western countries. Specifically, it (i) reviews the state of the art on kratom pharmacology and identification; (ii) provides a comprehensive overview of kratom use cross-culturally; (iii) explores the subjective experiences of users; (iv) identifies potential risks and side-effects related to its consumption. Finally, it concludes that the use of kratom is not negligible, especially for self-medication, and more clinical, pharmacological, and socioanthropological studies as well as a better international collaboration are needed to tackle this marginally explored phenomenon.
    Matched MeSH terms: Central Nervous System Stimulants
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