Puspha Sinnayah

• PhD
• Professor at Victoria University

In this Special Issue (SI), we have published recent scholarship addressing (a) narrative ways of knowing, (b) the diversity of methods used for researching experience and (c) issues related to the use of narrative to explore the experiences of individuals within an educational context [...]

Background: Obesity is a risk factor for developing cardiovascular diseases (CVDs) by impairing normal vascular function. Natural products are gaining momentum in the clinical setting due to their high efficacy and low toxicity. Caralluma fimbriata extract (CFE) has been shown to control appetite and promote weight loss; however, its effect on vasc...

Online teaching in higher education has become increasingly prevalent, especially in light of the COVID-19 pandemic. While teaching online offers many benefits, it also presents several challenges. Sharing one’s lived experiences as an educator is essential to improving one’s teaching skills and enhancing the learning outcomes for the students. Her...

The number of students enrolling in higher level mathematics units at high school have been in decline for a number of years. This is of particular concern when they then continue their studies within undergraduate STEM disciplines at University, leading academics to search for better methods to support mathematical instruction. The aim of this stu...

Behavioral studies are commonly used as a standard procedure to evaluate anxiety and depression in animal models. Recently, different methods have been developed to improve data collection and analysis of the behavioral tests. Currently available methods, including manual analysis and commercially available products, are either time-consuming or co...

Foundational knowledge in Anatomy and Physiology is integral to all health courses, however, first year students often find the volume and complexity of the concepts challenging (Vitali et al., 2020). Furthermore, our typical demographic student profile comes from a low socioeconomic status with a limited Science background. To help students with t...

Methamphetamine (METH) is a highly addictive drug abused by millions of users worldwide, thus becoming a global health concern with limited management options. The inefficiency of existing treatment methods has driven research into understanding the mechanisms underlying METH-induced disorders and finding effective treatments. This study aims to un...

Student engagement and its measurement remain contested by different research disciplines that aim to evaluate education. In computer analytics, engagement is momentary, and longer-term engagement arises from accumulated momentary engagement. By contrast, policymakers see engagement as fundamentally longer-term, emerging from the student’s identifi...

In 2018, Victoria University adopted a new teaching delivery model, now known as the Block Teaching Model (BTM). The aim of this study focuses on how this new approach to teaching has impacted student learning and academic success in particular from students who come from a disadvantaged background, compared with those who come from a non-disadvant...

During semester one of 2020, the units ‘Functional Anatomy of the Trunk’ and ‘Functional Anatomy of the Limbs’ which focus on human topographical anatomy were re-designed into an online delivery format and taught remotely in response to the COVID-19 lockdown. It was expected that the move to remote teaching would negatively impact student perceptio...

The amalgamation of educational technologies in higher education is widespread and has become essential for contemporary practice on a large scale. Foundational anatomy and physiology knowledge is integral to all courses in health education. To tackle the volume and complexity of the content taught at the foundation level, the incorporation of onli...

This study examines the impact on academic success of two different models of teaching for repeating students. Students who failed in 2017 under the traditional model of teaching, involving a 12 week semester with lectures and tutorials, were exposed the following year to the newly introduced “block model” of teaching, whereby students study one un...

This study examines the use of three computer programs designed for the study of gross anatomy; An@tomedia Online, AnatomyTV, and Thieme, as in-class learning support programs within the newly adopted “Block model” of teaching delivery at Victoria University. Victoria University is the first and only Australian university to have introduced a block...

Bioscience is a foundational unit (subject) of undergraduate allied health degree programs, providing students the scientific basis underpinning their clinical practice. However, despite its significance, bioscience is a difficult academic hurdle for many students to master. The introduction of active learning strategies, including small team-based...

Introduction In Prader–Willi syndrome (PWS), nonprotein coding small nucleolar (sno) RNAs are involved in the paternally deleted region of chromosome 15q11.2‐q13, which is believed to cause the hyperphagic phenotype of PWS. Central to this is SnoRNA116. The supplement Caralluma fimbriata extract (CFE) has been shown to decrease appetite behavior in...

Insulin regulated aminopeptidase (IRAP) co-localises with the glucose transporter 4 (GLUT4) in GLUT4 storage vesicles (GSV) in insulin-responsive cells. In response to insulin, IRAP is the only transmembrane enzyme known to translocate together with GLUT4 to the plasma membrane in adipocytes and muscle cells. Although the intracellular region of IR...

Prader-Willi syndrome (PWS) is a neurodevelopmental disorder resulting from a deletion in the expression of the paternally derived alleles in the region of 15q11-q13. PWS has a prevalence rate of 1:10,000-1:30,000 and is characterized by marked endocrine abnormalities including growth hormone deficiency and raised ghrelin levels. The hyperphagic ph...

The mechanism of action of the combination therapy, naltrexone/bupropion (NB), for obesity has not been fully described to date. Weight loss attempts rarely result in long-term success. This is likely a result of complex interactions among multiple peripheral and CNS systems that defend against weight loss, and may explain the overwhelming lack of...

The melanocortin-4 receptor (MC4R) is well recognized as an important mediator of body weight homeostasis. Activation of MC4R causes dramatic weight loss in rodent models, and mutations in human are associated with obesity. This makes MC4R a logical target for pharmacological therapy for the treatment of obesity. However, previous studies in rodent...

Leptin regulates body weight in mice by decreasing appetite and increasing sympathetic nerve activity (SNA), which increases energy expenditure in interscapular brown adipose tissue (iBAT). Diet-induced obese mice (DIO) are resistant to the anorectic actions of leptin. We evaluated whether leptin still stimulated sympathetic outflow in DIO mice. We...

To address the relative contribution of central and peripheral angiotensin II (ANG II) type 1A receptors (AT(1A)) to blood pressure and volume homeostasis, we generated a transgenic mouse model [neuron-specific enolase (NSE)-AT(1A)] with brain-restricted overexpression of AT(1A) receptors. These mice are normotensive at baseline but have dramatical...

Effects of IP AM251 on c-Fos and POMC-EGFP co-localization in POMC-EGFP mice. ARH slices were stained for c-Fos and EGFP expression. c-Fos staining indicated in brightfield images and POMC-EGFP neurons shown in fluorescence (FITC-green). Red arrows indicate c-Fos and POMC-EGFP co-localized cells. A, c-Fos activation in response to IP saline; B, c-F...

Representative photomicrographs showing c-Fos IR in response to IP saline, WIN 55212-2 and AM251 administration in Ay mice. A, B, C, c-Fos activation in response to saline in the NAc, PVH and NTS. D, E, F, Increased c-Fos IR in response to IP WIN 55,212-2. G, H, I, c-Fos IR in response to IP AM251. ac, anterior commissure; 3V, third ventricle, AP,...

Effects of WIN 55,212-2 and AM251 on α-MSH release from POMC neurons of the hypothalamus. There was no significant effect on α-MSH release (fmol/ml) from POMC neurons by cannabinoids. All values are expressed as mean±SEM. (0.14 MB TIF)

Representative photomicrographs showing c-Fos IR in response to intra-VTA administration of AM251 in the VMH and DMH in WT mice. Inset diagram is representative of VTA cannulation placement with the arrow indicating the tip of the guide cannula; the injector extends 1 mm further for injections. A, c-Fos IR in response to intra-VTA saline. B, c-Fos...

Olanzapine (OLZ), one of the second-generation atypical antipsychotics (SGAs), has shown relative advantages in patient adherence and outcomes. However, OLZ has also been associated with a higher incidence of weight gain than most other SGAs. Excessive weight gain may in turn contribute to long-term health concerns for some individuals. Zonisamide...

Cannabinoids, the active components of marijuana, stimulate appetite, and cannabinoid receptor-1 (CB1-R) antagonists suppress appetite and promote weight loss. Little is known about how CB1-R antagonists affect the central neurocircuitry, specifically the melanocortin system that regulates energy balance. Here, we show that peripherally administere...

The mechanism controlling cell-specific Ang II production in the brain remains unclear despite evidence supporting neuron-specific renin and glial- and neuronal-specific angiotensinogen (AGT) expression. We generated double-transgenic mice expressing human renin (hREN) from a neuron-specific promoter and human AGT (hAGT) from its own promoter (SRA...

Despite high leptin levels, most obese humans and rodents lack responsiveness to its appetite-suppressing effects. We demonstrate that leptin modulates NPY/AgRP and alpha-MSH secretion from the ARH of lean mice. High-fat diet-induced obese (DIO) mice have normal ObRb levels and increased SOCS-3 levels, but leptin fails to modulate peptide secretion...

The subfornical organ (SFO) of the brain has long been considered a critical integrating center for the cardiovascular actions of the renin-angiotensin system (RAS). Early reports of angiotensin II (Ang II) immunoreactivity in the SFO and its neural projections to downstream cardiovascular nuclei raised the possibility that Ang II is produced local...

The prevalence of obesity, and the human and economic costs of the disease, creates a need for better therapeutics and better understanding of the physiological processes that balance energy intake and energy expenditure. Leptin is the primary signal from energy stores and exerts negative feedback effects on energy intake. In common obesity, leptin...

The publisher regrets that this article is an accidental duplication of an article that has already been published, doi: 10.1016/j.appet.2006.03.001 . The duplicate article has therefore been withdrawn.

With an ever-growing population of obese people as well as comorbidities associated with obesity, finding effective weight loss strategies is more imperative than ever. One of the challenges in curbing the obesity crisis is designing successful strategies for long-term weight loss and weight-loss maintenance. Currently, weight-loss strategies inclu...

The Cre/loxP system has shown promise for investigating genes involved in nervous system function and pathology, although its application for studying central neural regulation of cardiovascular function and disease has not been explored. Here, we report for the first time that recombination of loxP-flanked genes can be achieved in discrete cardiov...

The influence of urocortin (UCN) on ingestive behaviours and brain neural activity, as measured immunohistochemically by the presence of Fos protein, was determined in mice. Rat UCN was administered by continuous intracerebroventricular (ICV) or subcutaneous (SC) infusion. ICV infusion of UCN (100 ng/h, 14 days) transiently reduced daily food and w...

Angiotensin II (Ang II) has profound effects in the central nervous system (CNS), including promotion of thirst, regulation of vasopressin secretion, and modulation of sympathetic outflow. Despite its importance in cardiovascular and volume homeostasis, angiotensinergic mechanisms are incompletely understood in the CNS. Recently, a novel signaling...

To examine the physiological importance of brain angiotensin II type 1 (AT1) receptors, we developed a novel transgenic mouse model with rat AT1a receptors targeted selectively to neurons of the central nervous system (CNS). A transgene consisting of 2.8 kb of the rat neuron-specific enolase (NSE) 5' flanking region fused to a cDNA encoding the ful...

The systemic renin-angiotensin system (RAS) plays a critical role in cardiovascular (CV) homeostasis. All components of the RAS are also known to be produced cell-specifically within specific brain regions, although the role of the brain RAS relative to the systemic RAS has remained a puzzle due to the difficulty of dissecting these two systems. Se...

Circulating relaxin, like most (but not all) peptide hormones, probably does not readily pass across the blood-brain barrier. However, relaxin can exert influences on the brain, and in vitro autoradiographic binding [1] and physiological studies [2] suggest that it does this by binding to specific receptors in the subfornical organ and organum vasc...

Phosphorothioated antisense oligodeoxynucleotides (ODNs) that were complementary to various parts of the rat or sheep mRNA encoding angiotensinogen were synthesized by conventional techniques. Their effectiveness as blockers of angiotensinogen synthesis in the brain was tested by bioassay. This involved measuring the effect of centrally administere...

19 To examine the functional consequences of overexpression of AT1 receptors selectively in brain of both normal mice and in mice otherwise lacking endogenous AT1 receptors, we generated a novel transgenic model with AT1 receptors targeted selectively to neurons in the CNS. A fusion transgene consisting of 2.8 Kb of rat neuron-specific enolase(NSE)...

The purpose of the study was to determine whether iv infusion of relaxin would acutely stimulate water drinking in rats and, if it did, whether such drinking is affected by other dipsogenic stimuli or is blocked by centrally administered losartan. iv infusions of human gene 2 relaxin at doses of 25, 40, 55, or 80 microg/kg x h for 1 h induced dose-...

The purpose of the study was to determine whether iv infusion of relaxin would acutely stimulate water drinking in rats and, if it did, whether such drinking is affected by other dipsogenic stimuli or is blocked by centrally administered losartan. iv infusions of human gene 2 relaxin at doses of 25, 40, 55, or 80 μg/kg·h for 1 h induced dose-depend...

The role of centrally synthesised angiotensinogen in neural mechanisms subserving water drinking in rats was investigated by injecting antisense oligonucleotides complementary to rat angiotensinogen mRNA into the brain with the aim of inhibiting cerebral angiotensinogen synthesis. Phosphorothioate antisense oligonucleotides (18 mer) encompassing th...

The effectiveness of antisense oligonucleotides (ODNs) to angiotensinogen on intracerebrovenricularly injected renin induced thirst was investigated. As a corollary, information would be gained about the role of centrally synthesised angiotensinogen in the neural mechanisms subserving water drinking in rats. Stable, easily synthesised phosphorothio...