Publications by authors named "Sidney Williams"

The hippocampus is pivotal in integrating emotional processing, learning, memory, and reward-related behaviors. The dorsal hippocampus (dHPC) is particularly crucial for episodic, spatial, and associative memory, and has been shown to be necessary for context- and cue-associated reward behaviors. The nucleus accumbens (NAc), a central structure in the mesolimbic reward pathway, integrates the salience of aversive and rewarding stimuli.

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Background: CNIH3 is an AMPA receptor (AMPAR) auxiliary protein prominently expressed in the dorsal hippocampus (dHPC), a region that plays a critical role in spatial memory and synaptic plasticity. However, the effects of CNIH3 on AMPAR-dependent synaptic function and behavior have not been investigated.

Methods: We assessed a gain-of-function model of Cnih3 overexpression in the dHPC and generated and characterized a line of Cnih3 C57BL/6 mice.

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Mitochondrial fragmentation from defective fusion or unopposed fission contributes to many neurodegenerative diseases. Small molecule mitofusin activators reverse mitochondrial fragmentation , promising a novel therapeutic approach. The first-in-class mitofusin activator, , has a short plasma and limited neurological system bioavailability, conferring "burst activation".

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Two major questions about addictive behaviors need to be explained by any worthwhile neurobiological theory. First, why do people seek drugs in the first place? Second, why do some people who use drugs seem to eventually become unable to resist drug temptation and so become "addicted"? We will review the theories of addiction that address negative-reinforcement views of drug use (i.e.

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Insulin-like growth factor II (IGF2) enhances memory in rodents via the mannose-6-phosphate receptor (M6PR), but the underlying mechanisms remain poorly understood. We found that human IGF2 produces an enhancement of both synaptic transmission and neurite outgrowth in the marine mollusk Aplysia californica. These findings were unexpected since Aplysia lack the mammal-specific affinity between insulin-like ligands and M6PR.

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Introduction And Aims: An understanding of the relationship between hepatitis C viral (HCV) infection and contextual factors such as imprisonment may contribute to the development of targeted treatment and prevention programs. We examine the associations of imprisonment and drug dependence with lifetime exposure to HCV, and whether these associations differ for Aboriginal and Torres Strait Islander and non-Indigenous people who inject drugs.

Design And Methods: Respondent-driven sampling was used in major cities and 'peer recruitment' in regional towns of Queensland to obtain a community sample of people who injected drugs, which comprised 243 Indigenous and 227 non-Indigenous participants who had ever been tested for HCV.

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The formation and maintenance of an organism are highly dependent on the orderly control of cell growth, differentiation, death, and migration. These processes are tightly regulated by signaling cascades in which a limited number of molecules dictate these cellular events. While these signaling pathways are highly conserved across species and cell types, the functional outcomes that result from their engagement are specified by the context in which they are activated.

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Introduction And Aims: Despite over-representation of Indigenous Australians in sentinel studies of injecting drug use, little is known about relevant patterns of drug use and dependence. This study compares drug dependence and possible contributing factors in Indigenous and non-Indigenous Australians who inject drugs.

Design And Methods: Respondent-driven sampling was used in major cities and 'peer recruitment' in regional towns of Queensland to obtain a community sample of Indigenous (n = 282) and non-Indigenous (n = 267) injectors.

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GABAergic interneurons provide the main source of inhibition in the neocortex and are important in regulating neocortical network activity. In the presence 4-aminopyridine (4-AP), CNQX, and D-APV, large amplitude GABAA-receptor mediated depolarizing responses were observed in the neocortex. GABAergic networks are comprised of several types of interneurons, each with its own protein expression pattern, firing properties, and inhibitory role in network activity.

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Objective: Hepatitis B virus (HBV) infection remains an important cause of morbidity and mortality in Aboriginal and Torres Strait Islander people, who have high rates of infection compared with non-Indigenous Australians. We aimed to increase the evidence base around HBV in Aboriginal and Torres Strait Islander people through an analysis of routine clinical encounter data.

Design: A cross-sectional study of de-identified records from electronic patient systems over 5 years (8 January 2009 to 11 July 2013).

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Hyperpolarization-activated, cyclic nucleotide-gated, nonspecific cation (HCN) channels have a well-characterized role in regulation of cellular excitability and network activity. The role of these channels in control of epileptiform discharges is less thoroughly understood. This is especially pertinent given the altered HCN channel expression in epilepsy.

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Mate choice is fundamental to sexual selection, yet little is known about underlying physiological mechanisms that influence female mating decisions. We investigated the endocrine underpinnings of female mate choice in the African cichlid Astatotilapia burtoni, a non-seasonal breeder. In addition to profiling behavioral and hormonal changes across the female reproductive cycle, we tested two hypotheses regarding possible factors influencing female mate choice.

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Recent findings indicate that rats navigate in spatial tasks such as the Morris water maze (MWM) using a local cue-based reference frame rather than a distal cue-based reference frame. Specifically, rats swim in a particular direction to a location relative to pool-based cues, rather than to an absolute location defined by room-based cues. Neural mechanisms supporting this bias in rodents for relative responding in spatial tasks are not yet understood.

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