Understanding methiopropamine, a new psychoactive substance: an in-depth review on its chemistry, pharmacology and implications to human health.

Methiopropamine or 1-(thiophen-2-yl)-2-methylaminopropane (MPA) is a thiophene ring-based structural analogue of methamphetamine, first synthesized in 1942 but become popular when it started to be available for purchase on websites selling 'legal highs' since 2010. While it is legally controlled in many countries, it remains readily accessible and frequently encountered in recreational settings. The growing prevalence of MPA use results in new therapeutic challenges.

Tapping into 5-HT Receptors to Modify Metabolic and Immune Responses.

5-hydroxytryptamine type 3 (5-HT) receptors are ligand gated ion channels, which clearly distinguish their mode of action from the other G-protein coupled 5-HT or serotonin receptors. 5-HT receptors are well established targets for emesis and gastrointestinal mobility and are used as adjunct targets in treating schizophrenia. However, the distribution of these receptors is wider than the nervous system and there is potential that these additional sites can be targeted to modulate inflammatory and/or metabolic conditions.

Visualising functional 5-HT receptors containing A and C subunits at or near the cell surface.

Five different subunits of the human serotonin 3 (5-hydroxytrptamine 3; 5-HT) receptor exist and these are present in both central and peripheral systems. Different subunits alter the efficacy of 5-HT receptor antagonists used to treat diarrhoea predominant-irritable bowel syndrome, chemotherapy induced nausea and vomiting and depression. Cell surface arrangement of 5-HT receptor complexes and the contribution of C, D and E subunits to receptor function is poorly understood.

Potential roles of 5-HT receptor (5-HTR) antagonists in modulating the effects of nicotine.

5-HTR antagonists such as ondansetron, granisetron and tropisetron have been clinically used to treat nausea and vomiting in chemotherapy patients. However, current study and research revealed novel potentials of these ligands in other diseases like inflammation, Alzheimer's, and drug abuse. Towards utilising these drugs as anti-smoking agents to treat nicotine dependence problem, there are conflicting reports regarding the potential of these ligands in modulating the effects of nicotine in both human and animal behavioural studies.

The C and E subunits of the serotonin 5-HT receptor subtly modulate electrical properties of the receptor.

Serotonin type 3 (5-hydroxytrptamine-3, 5-HT) receptors are ligand-gated cation channels present in both central and peripheral nervous systems. In humans there are five different subunits (A, B, C, D and E) of 5-HT receptors which can form homomeric or heteromeric receptors that may account for discrepancies in patient responses to treatments. The present study commences characterisation of the profiles of human 5-HT receptors containing C and/or E subunits.

Distribution of 5-HT3, 5-HT4, and 5-HT7 Receptors Along the Human Colon.

Background/aims: Several disorders of the gastrointestinal tract are associated with abnormal serotonin (5-HT) signaling or metabolism where the 5-HT3 and 5-HT4 receptors are clinically relevant. The aim was to examine the distribution of 5-HT3, 5-HT4, and 5-HT7 receptors in the normal human colon and how this is associated with receptor interacting chaperone 3, G protein coupled receptor kin-ases, and protein LIN-7 homologs to extend previous observations limited to the sigmoid colon or the upper intestine.

Methods: Samples from ascending, transverse, descending, and sigmoid human colon were dissected into 3 separate layers (mucosa, lon-gitudinal, and circular muscles) and ileum samples were dissected into mucosa and muscle layers (n = 20).

Low-dose photon irradiation response of Ge and Al-doped SiO2 optical fibres.

We have investigated the thermoluminescent response and fading characteristics of germanium- and aluminium-doped SiO(2) optical fibres. These optical fibres were placed in a solid phantom and irradiated using 6 and 10 MV photon beams at doses ranging from 0.02 to 0.