scholarly journals Progressing our understanding of the impacts of nutrition on the brain and behaviour in anorexia nervosa: a tyrosine case study example

2021 ◽  
Vol 9 (1) ◽  
Author(s):  
Melissa Hart ◽  
David Sibbritt ◽  
Lauren T. Williams ◽  
Kenneth P. Nunn ◽  
Bridget Wilcken
Keyword(s):  
Anorexia Nervosa ◽  
New England ◽  
Ethics Committee ◽  
Adjunct Treatment ◽  
Human Research Ethics ◽  
Pharmacological Response ◽  
Efficacious Treatment ◽  
The Brain ◽  
Noradrenaline And Adrenaline

AbstractAnorexia nervosa is a severe and complex illness associated with a lack of efficacious treatment. The effects of nutrition on the brain and behaviour is of particular interest, though an area of limited research. Tyrosine, a non-essential amino acid, is a precursor to the catecholamines dopamine, noradrenaline and adrenaline. Ongoing tyrosine administration has been proposed as an adjunct treatment through increasing blood tyrosine sufficiently to facilitate brain catecholamine synthesis. The effects of tyrosine supplementation in adolescents with anorexia nervosa remain to be tested. This study had approval from the Hunter New England Human Research Ethics Committee (06/05/24/3.06). We aimed to explore the pharmacokinetics of tyrosine loading in adolescents with anorexia nervosa (n = 2) and healthy peers (n = 2). The first stage of the study explored the pharmacological response to a single, oral tyrosine load in adolescents (aged 12–15 years) with anorexia nervosa and healthy peers. Participants with anorexia nervosa then continued tyrosine twice daily for 12 weeks. There were no measured side effects. Peak tyrosine levels occurred at approximately two to three hours and approached baseline levels by eight hours. Variation in blood tyrosine response was observed and warrants further exploration, along with potential effects of continued tyrosine administration in anorexia nervosa.

scholarly journals Oral Tyrosine Supplementation Facilitates Conditions for the Preferential Transport of Tyrosine Across the Blood-Brain Barrier in Anorexia Nervosa: a Case Study Series

2021 ◽  
Author(s):  
Melissa Hart ◽  
David Sibbritt ◽  
Lauren Williams ◽  
Kenneth Nunn ◽  
Bridget Wilcken
Keyword(s):  
Anorexia Nervosa ◽  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Adjunct Treatment ◽  
Blood Brain ◽  
Efficacious Treatment ◽  
Preferential Transport ◽  
Plasma Tyrosine ◽  
Over Time

Abstract Background: Anorexia nervosa is a severe and complex illness associated with a lack of efficacious treatment. Ongoing tyrosine administration has been proposed as a possible treatment through increasing blood tyrosine sufficiently to facilitate brain catecholamine synthesis. Saturation with the noradrenergic precursor tyrosine could alleviate noradrenergic dysregulation with subsequent reduction in dietary restraint and eating, weight and shape concern. The effects of tyrosine supplementation in adolescents with anorexia nervosa remain to be tested. This feasibility study aimed to explore whether an oral tyrosine dosage raises plasma tyrosine sufficiently in adolescents with anorexia nervosa and healthy peers and is sustained over time to allow conditions for the preferential transport across the blood-brain barrier. Case Presentation: The first stage of this study explored the pharmacological response to a single, oral tyrosine load in adolescents (aged 12-15 years) with anorexia nervosa (n=2) and healthy peers (n=2). The second stage explored the pharmacological and psychological response to ongoing tyrosine administration in adolescents with anorexia nervosa. Peak tyrosine levels occurred at approximately two-three hours and approached baseline levels by eight hours. Blood tyrosine elevation was maintained over time in participants with anorexia nervosa. Some improvements in participant psychological tests were evident. There were no measured side effects. Conclusions: The considerable blood tyrosine increase appeared sufficient to facilitate conditions for the preferential transport of tyrosine across the blood-brain barrier which has the potential to improve noradrenergic brain function in people with anorexia nervosa. Further exploration of tyrosine as an adjunct treatment in anorexia nervosa is warranted.

scholarly journals Why Did You Not Act on Our Suggestion? Regulatory and Growth-Oriented Opportunities During Ethical Review: A Case Study

SAGE Open ◽  
2020 ◽  
Vol 10 (2) ◽  
pp. 215824402092058
Author(s):  
Sean G. Dicks ◽  
Ian J. Pieper ◽  
Holly L. Northam ◽  
Frank M. P. van Haren ◽  
Douglas P. Boer
Keyword(s):  
Research Ethics ◽  
Ethics Committee ◽  
Ethical Review ◽  
Human Research Ethics ◽  
Apply Research ◽  
Differences Of Opinion ◽  
Research Plan ◽  
Conducting Research ◽  
Human Participants

In Australia, before conducting research with human participants, researchers must have their research plan reviewed by a Human Research Ethics Committee (HREC) to ensure that proposed methods meet ethical requirements and protect the welfare of participants. In addition, it has been proposed that HRECs can contribute to a novice researcher’s ethical mindfulness. To explore this suggestion, the current self-reflective case study examines the dialogue between a PhD candidate and the HREC that reviewed his proposed study of family bereavement in the context of the potential for organ donation. Findings suggest that when a respectful, problem-solving attitude is adopted by both parties, a learning environment evolves where diverse views, differences of opinion, and novel solutions are tolerated. In this context, the research plan is improved and the novice researcher’s ability to apply research ethics is developed. Simultaneously, members of the HREC gain practice in the identification of ethical dilemmas and the application of ethical principles that help resolve those dilemmas.

Seeking Approval from Universities to Research the Views of Their Staff. Do Gatekeepers Provide a Barrier to Ethical Research?

2022 ◽  
pp. 155626462110683
Author(s):  
Katherine Christian ◽  
Carolyn Johnstone ◽  
Jo-ann Larkins ◽  
Wendy Wright
Keyword(s):  
Informed Consent ◽  
Research Ethics ◽  
Ethics Committee ◽  
University Staff ◽  
Institutional Approval ◽  
Human Research ◽  
Human Research Ethics ◽  
Risk Research ◽  
Case Basis

A “gatekeeper” controls access to an organization; “gatekeeper approval” is often needed before external research can take place within an organization. We explore the need for gatekeeper approval for research with university staff employing, as a case study, a project which collected data in Australia. This case study addresses known issues, seemingly rarely addressed in the literature. The Human Research Ethics Committee (HREC)'s requirement for approval from individual universities to approach their staff brought significant consequences, exacerbated by the lack of university procedures for such approvals. Simultaneously, since invitations could legitimately be distributed via other avenues, such approval was superfluous. We recommend the HREC's blanket requirement for institutional approval instead be considered on a case-by-case basis depending on the risk of the research, and perhaps waived for low-risk research where participants are able to provide informed consent, and that universities establish processes to deal with requests from external researchers.

Morphological Changes in the Brain of Acutely Ill and Weight-Recovered Patients with Anorexia Nervosa

2014 ◽  
Vol 42 (1) ◽  
pp. 7-18 ◽  
Author(s):  
Jochen Seitz ◽  
Katharina Bühren ◽  
Georg G. von Polier ◽  
Nicole Heussen ◽  
Beate Herpertz-Dahlmann ◽  
...  
Keyword(s):  
Anorexia Nervosa ◽  
Cognitive Deficits ◽  
Time Course ◽  
Morphological Changes ◽  
Meta Analysis ◽  
Short Term ◽  
Clinical Prognosis ◽  
Qualitative Review ◽  
Brain Changes ◽  
The Brain

Objective: Acute anorexia nervosa (AN) leads to reduced gray (GM) and white matter (WM) volume in the brain, which however improves again upon restoration of weight. Yet little is known about the extent and clinical correlates of these brain changes, nor do we know much about the time-course and completeness of their recovery. Methods: We conducted a meta-analysis and a qualitative review of all magnetic resonance imaging studies involving volume analyses of the brain in both acute and recovered AN. Results: We identified structural neuroimaging studies with a total of 214 acute AN patients and 177 weight-recovered AN patients. In acute AN, GM was reduced by 5.6% and WM by 3.8% compared to healthy controls (HC). Short-term weight recovery 2–5 months after admission resulted in restitution of about half of the GM aberrations and almost full WM recovery. After 2–8 years of remission GM and WM were nearly normalized, and differences to HC (GM: –1.0%, WM: –0.7%) were no longer significant, although small residual changes could not be ruled out. In the qualitative review some studies found GM volume loss to be associated with cognitive deficits and clinical prognosis. Conclusions: GM and WM were strongly reduced in acute AN. The completeness of brain volume rehabilitation remained equivocal.

Starving the brain: Structural abnormalities and cognitive impairment in adolescents with anorexia nervosa

2001 ◽  
Vol 6 (2) ◽  
pp. 146-152 ◽  
Author(s):  
Debra K. Katzman ◽  
Bruce Christensen ◽  
Arlene R. Young ◽  
Robert B. Zipursky
Keyword(s):  
Anorexia Nervosa ◽  
Cognitive Impairment ◽  
Structural Abnormalities ◽  
The Brain

Asian American Dropouts: A Case Study of Vietnamese and Chinese High School Students in a New England Urban School District

2009 ◽  
Vol 7 (1) ◽  
pp. 83-104 ◽  
Author(s):  
Phitsamay Uy
Keyword(s):  
High School ◽  
High School Students ◽  
New England ◽  
Asian American ◽  
Dropout Rates ◽  
School Students ◽  
Study Support ◽  
Asian American Student ◽  
K 12

In the world of K–12 education, the growing numbers of dropouts are a major concern. This article examines the dropout rates of Chinese and Vietnamese high school students. Using logistic regression analysis, this article examines the influence of ethnicity, gender, and socioeconomic status (SES) on dropout rates. The distinct contribution of this analysis lies within the intraethnic comparisons within the Asian American student population and its use of longitudinal data. The results of the study support existing research that gender and SES are related to dropout rates. Moreover, an interesting interaction between ethnicity and SES exists.

scholarly journals Basal Ganglia Herniation into the Fourth Ventricle

1997 ◽  
Vol 24 (1) ◽  
pp. 62-63 ◽  
Author(s):  
Mensura Altumbabic ◽  
Marc R. Del Bigio ◽  
Scott Sutherland
Keyword(s):  
Basal Ganglia ◽  
Intracerebral Hemorrhage ◽  
Fourth Ventricle ◽  
Transtentorial Herniation ◽  
Intracerebral Bleeding ◽  
Rare Phenomenon ◽  
The Brain

ABSTRACT:Background:Transtentorial herniation of large cerebral fragments is a rare phenomenon.Method:Case StudyResults:Examination of the brain of a 35-year-old male showed massive intracerebral hemorrhage resulting in displacement of basal ganglia components into the fourth ventricle.Conclusions:Sufficiently rapid intracerebral bleeding can dissect fragments of cerebrum and displace them long distances across the tentorial opening.

scholarly journals Delivery of Thyronamines (TAMs) to the Brain: A Preliminary Study

Molecules ◽  
2021 ◽  
Vol 26 (6) ◽  
pp. 1616
Author(s):  
Nicoletta di Leo ◽  
Stefania Moscato ◽  
Marco Borso' ◽  
Simona Sestito ◽  
Beatrice Polini ◽  
...  
Keyword(s):  
High Performance ◽  
In Vitro Model ◽  
New Drugs ◽  
Therapeutic Approaches ◽  
Neuroprotective Effects ◽  
Pharmacological Response ◽  
Preliminary Study ◽  
Vitro Model ◽  
The Brain

Recent reports highlighted the significant neuroprotective effects of thyronamines (TAMs), a class of endogenous thyroid hormone derivatives. In particular, 3-iodothyronamine (T1AM) has been shown to play a pleiotropic role in neurodegeneration by modulating energy metabolism and neurological functions in mice. However, the pharmacological response to T1AM might be influenced by tissue metabolism, which is known to convert T1AM into its catabolite 3-iodothyroacetic acid (TA1). Currently, several research groups are investigating the pharmacological effects of T1AM systemic administration in the search of novel therapeutic approaches for the treatment of interlinked pathologies, such as metabolic and neurodegenerative diseases (NDDs). A critical aspect in the development of new drugs for NDDs is to know their distribution in the brain, which is fundamentally related to their ability to cross the blood–brain barrier (BBB). To this end, in the present study we used the immortalized mouse brain endothelial cell line bEnd.3 to develop an in vitro model of BBB and evaluate T1AM and TA1 permeability. Both drugs, administered at 1 µM dose, were assayed by high-performance liquid chromatography coupled to mass spectrometry. Our results indicate that T1AM is able to efficiently cross the BBB, whereas TA1 is almost completely devoid of this property.

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