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Cross-reinstatement Models Of Mitragynine-morphine Drugseeking Addictive Behaviour And Dopaminergic Involvement In Sprague-dawley Rats
(2024-09)
Japarin, Rima Atria
Kratom (Mitragyna speciosa Korth.) is a medicinal herb which gained fame for its potential as an opioid substitute. Nevertheless, little is known about the abuse potential of its major alkaloid, mitragynine, especially in relapse to drug abuse. Therefore, the extinction-reinstatement models including the conditioned place preference (CPP) and intravenous self-administration (IVSA) paradigms, were employed to model the relapse mechanism in Sprague-Dawley rats. In the first part of the study, mitragynine administered non-contingently in morphine-addicted rats following extinction was investigated. Following CPP acquisition induced by either mitragynine (30 mg/kg, i.p.) or morphine (10 mg/kg, i.p.), rats were subjected to repeated CPP extinction sessions. A priming injection of morphine (1, 3 and 10 mg/kg, i.p.) dose-dependently reinstated mitragynine-induced CPP. Similarly, a priming injection of mitragynine (3, 10 and 30 mg/kg, i.p.) dose-dependently reinstated morphine-induced CPP. In the IVSA study, rats were initially trained to intravenously self-administer morphine (0.5 mg/kg/infusion) under a fixed ratio-3 schedule of reinforcement. Removal of both morphine infusions and drug-associated cues led to the extinction of drug-seeking behaviour. Reinstatement tests were made following a randomised order of mitragynine (3, 10 and 30 mg/kg), morphine (5 mg/kg) and vehicle injections. Mitragynine priming at 10 mg/kg resulted in the reinstatement of morphine-seeking behaviour but higher mitragynine dose (30 mg/kg) suppressed the seeking response. In order to understand the mechanism underlying the rewarding properties of mitragynine in relapse, the involvement of dopaminergic system in the acquisition, expression and reinstatement phase was studied. Therefore, the second part of the study was conducted using a selective dopamine (DA) D1 receptor antagonist, SCH-23390. For acquisition, rats were pre-treated with SCH- 23390 (0, 0.1 and 0.3 mg/kg, i.p.) prior to mitragynine (10 mg/kg) conditioning sessions. Next, the effects of DA D1 receptor antagonist were tested on the expression of mitragynine-induced CPP. Subsequently, the effects of a mitragyninepriming dose (5 mg/kg) on the reinstatement of extinguished CPP were tested. The results showed that SCH-23390 dose-dependently suppressed the acquisition of mitragynine-induced CPP but no effect on the expression of mitragynine-induced CPP. Additionally, blockade of the D1-like receptor during conditioning did not prevent mitragynine priming effects in CPP reinstatement test, implying no role of the DA D1 receptor in reinstatement sensitivity. Altogether, these findings suggest that exposure to mitragynine may increase the likelihood of relapsing to opioids, suggesting that mitragynine’s potential as an opioid management treatment merits further scientific assessment of its ability to trigger relapse to opioid abuse.
Critical Discourse Analysis Of Human Rights Violations In The Washington Post And New York Times Online Newspapers: Post Isis Iraq Era
(2024-06)
Qaysi, Fouad Hussein Ali Al
The present study investigated the depiction of human rights violations in iraq post-isis era in the american online newspapers, particularly violating the right to peaceful assembly through the demonstrations that occurred in 2019. This study focused on examining the macro- and micro- semantic structures of the news articles and ideological representations through employing van dijk‘s (1980) approach to semantic macrostructure and van dijk‘s (1998) theory of ideology. Furthermore, the historical background information and political critique were presented through applying wodak‘s (2001) discourse historical theory to facilitate discourse interpretation and maintain objectivity in the analytical process. The data was collected from 6 articles in each of the two american online newspapers, namely, the washington post and new york times news in 2019. Analytically, the macro-level revealed an agreement between both newpapers on the thematic structure about hrvs in iraq, stating that the protests in iraq on demanding basic rights, were dealt with violently by the government, leading to the government's fall.
Phytochemical Characterization And Wound Healing Property Of Euphorbia Hirta L.
(2024-05)
Ayoona, Daniah Fouad Abdulameer
Euphorbia hirta l, an annual plant that belongs to the euphorbiaceae family, is a common traditional remedy for several diseases. Currently, there are few investigations on this plant as a treatment for wound healing, particularly the bioactive compounds and mechanism of action. Therefore, this study focused on isolating the main active compounds associated with the wound-healing activity of e. Hirta. The aerial parts of the plant were collected from the northern part of malaysia and iraq and then were extracted with solvents of different polarities: hexane, chloroform, methanol, and water. All extracts were screened for total phenolic and flavonoid contents and antioxidant and anti-inflammatory activities. Additionally, all extracts were assessed for potential wound healing activity by measuring the migration and cell viability of human fibroblast cells, hs27. Then the methanol extracts were further fractionated to identify the active compounds. The structure elucidation of isolated compounds was confirmed using liquid chromatography-mass spectrometry (lcms/ ms), nuclear magnetic resonance (nmr), and high-performance liquid chromatography (hplc). Subsequently, molecular docking was performed on the isolated compounds to analyse their binding interactions with the glycogen synthase kinase-3β (gsk3b) and casein kinase 1 (ck1) proteins. The level of mrna expression of four cytokines (il1b, il6, tnf, and col1a1) after treating human fibroblasts with different compounds were assayed. The e. Hirta extract yielded a different type of compounds: kaempferol,
Tropical Bed Bug (Hemiptera: Cimicidae) Infestation, Public Awareness, Morphological Identification And Population Genetic Structure In Iraq
(2025-05)
Baqir, Baqir Hussein Ali
Cimex hemipterus (f.), or tropical bed bugs, is an ectoparasite that primarily feeds on human blood. Tropical bed bugs have recently become in public health and are of social and economic importance. This study aimed to determine bed bug infestation, identify the bed bug species, and determine the level of awareness among the iraqi community regarding bed bug infestations in iraq. This study also examines the genetic structure and diversity of c. Hemitpterus populations in iraq. Bed bug infestation dynamics were determined by surveying 18 infested sites, including private homes, local hotels, and workers’ dormitories, across eight iraqi governorates between 2020 and 2021. Bed bug samples were collected from each infested site for further study. From the survey, most bed bug infestations in iraq primarily stem from migrant workers and the reuse of second-hand furniture and clothing. In terms of preferred harborage, wooden furniture was the common source (91.6%). Although a large number of respondents (43.8%) expressed "somewhat concerned" about bed bug infestations in iraq, there was a high level of unawareness (53.3%) regarding bed bug infestations. The mean pronotum width-to-length ratio of collected bed bug samples was less than 2.5mm these samples then underwent for molecular identification through partial sequences of mitochondrial coi and 16s rrna. Based on their morphological characteristics and dna sequence data, it can be affirmed that all collected bed bugs were c. Hemipterus. Moreover, the results indicated that c. Hemipterus is the sole bed bug species in iraq.
Fabrication And Investigation Of Al-Doped Zno Nanorods For Laser-Based Temperature Sensor Applications
(2024-05)
Azmi, Atiqah Nabieha
This work highlights the potential of random lasers as thermal laser-based sensor at room temperature within the uv-range. The work includes synthesis of zno nanorods, doping the zno, measuring the lasing, and laser-based sensing parameters. The zno nanorods were synthesized on glass substrate using chemical bath deposition (cbd) method for three hours at 96 °c and revealed an average nanorod height and diameter of 1200 nm and 176 nm, respectively. Al dopant is then introduced to the zno nanorods by dipping technique. To start, a broad range of al dopant concentrations (10 mm - 70 mm) at fixed doping duration of 100 s was investigated. The average height of zno nanorods decreased with increasing concentration of al due to the acidity of the doping solution. As a result, only zno doped with 10 mm concentration showed random lasing emission at a threshold of 17.83 mj/cm2 with a spectral width of 1.66 nm. Based on these results, doping duration (0 s to 80 s) was varied for a fixed concentration of 10 mm. A gradual increase of al % was observed and the average zno nanorods diameter did not change significantly with increasing doping duration (± 14 nm). All samples showed random lasing emission and zno nanorods doped for 40 s with 1.19 % of al showed lowest lasing threshold of 12.48 mj/cm2 with a spectral width of 1.76 nm. Finally, thermal laser nano-sensing were investigated. Zno nanorods doped for 60 s revealed a sensitivity as low as 0.001 c-1. In conclusion, zno doped for 40 s showed the best random lasing threshold and zno doped for 60 s showed the best sensing properties due to a narrower linewidth.