Development and appraisal of MRI contrast agents for the in vivo analysis of stem cell grafts

The work reported in this thesis deals with the need for efficient in vivo tracking and monitoring of grafted cells and their subsequent survival. It is considered in the context of cell transplantation for neurodegenerative disorders, particularly Huntington’s and Parkinson’s disease, although the scope for a good contrast agent to monitor cells in vivo goes far beyond this. There is currently no routine method used to follow cells in vivo and it is crucial for the advancement of cell transplantation studies, both in terms of providing powerful longitudinal analysis and for decreasing the number of animals necessary per experiment. MRI allows good contrast resolution and provides details on soft tissue anatomy without being harmful to the subject. By labeling cells with an MRI contrast agent the labeled cells can be distinguished from the surroundings and information on location is attained. A good MRI contrast agent can provide more information than this though, but to date there hasn’t been an MRI contrast agent developed that can simultaneously provide good signal and be reflective of the graft changes, while not affecting the cell’s viability. The feasibility for in vivo MRI scanning of three MRI contrast agents were tested and detailed below. In Chapter 3 we looked to utilise SPIOs as contrast agents. Since SPIOs are the most widely used of contrast agents they were tested in mouse ES cells, expanded whole ganglionic eminence and rat ventral mesencephalon and successfully labeled all cell types. Problems were discovered in reference to the needle track leaving an MRI visible track that eclipsed the area of graft deposition, and while SPIOs did not hamper graft survival, only large grafts extending out from the needle track could be reliably measured. Chapter 4 examined the generation of ferritin constructs for use as contrast agents. Transgenes based on the ferritin subunits provide MRI contrast by increasing the iron content of a cell. Both subunits, heavy and light, were transfected into mouse ES cells and expressed to improve signal compared to overexpressing the ferritin heavy transgene alone, which has been done in the literature. The expected change in T2 relaxation compared to control cell lines was observed in vitro. In Chapter 5 the applicability for in vivo use of Chemical Exchange Saturation Transfer (CEST) was tested. CEST involves the selective saturation of protons of particular compounds that are then indirectly detected through the water signal. Current 2D RARE scans to pick up CEST are slow and not really transferable to animal studies, due to the large increase in scan time for each extra image slice required, here alternative 3D FLASH scans were developed that still allowed the CEST contrast change to be observed over a whole sample in a reasonable time frame. A transgene based on CEST was tested in vivo and expression was lost even under antibiotic selection. Work in this thesis contributes some understanding towards the promises and pitfalls of three MRI contrast agents, two of which may ultimately be used more routinely for cell tracking in the future

Associations between breast cancer survivorship and adverse mental health outcomes: A matched population-based cohort study in the United Kingdom.

BACKGROUND: Breast cancer is the most common cancer diagnosed in women globally, and 5-year net survival probabilities in high-income countries are generally >80%. A cancer diagnosis and treatment are often traumatic events, and many women struggle to cope during this period. Less is known, however, about the long-term mental health impact of the disease, despite many women living several years beyond their breast cancer and mental health being a major source of disability in modern societies. The objective of this study was to quantify the risk of several adverse mental health-related outcomes in women with a history of breast cancer followed in primary care in the United Kingdom National Health Service, compared to similar women who never had cancer. METHODS AND FINDINGS: We conducted a matched cohort study using data routinely collected in primary care across the UK to quantify associations between breast cancer history and depression, anxiety, and other mental health-related outcomes. All women with incident breast cancer in the Clinical Practice Research Datalink (CPRD) GOLD primary care database between 1988 and 2018 (N = 57,571, mean = 62 ± 14 years) were matched 1:4 to women with no prior cancer (N = 230,067) based on age, primary care practice, and eligibility of the data for linkage to hospital data sources. Cox models were used to estimate associations between breast cancer survivorship and each mental health-related outcome, further adjusting for diabetes, body mass index (BMI), and smoking and drinking status at baseline. Breast cancer survivorship was positively associated with anxiety (adjusted hazard ratio (HR) = 1.33; 95% confidence interval (CI): 1.29-1.36; p < 0.001), depression (1.35; 1.32-1.38; p < 0.001), sexual dysfunction (1.27; 1.17-1.38; p < 0.001), and sleep disorder (1.68; 1.63-1.73; p < 0.001), but not with cognitive dysfunction (1.00; 0.97-1.04; p = 0.88). Positive associations were also found for fatigue (HR = 1.28; 1.25-1.31; p < 0.001), pain (1.22; 1.20-1.24; p < 0.001), receipt of opioid analgesics (1.86; 1.83-1.90; p < 0.001), and fatal and nonfatal self-harm (1.15; 0.97-1.36; p = 0.11), but CI was wide, and the relationship was not statistically significant for the latter. HRs for anxiety and depression decreased over time (p-interaction <0.001), but increased risks persisted for 2 and 4 years, respectively, after cancer diagnosis. Increased levels of pain and sleep disorder persisted for 10 years. Younger age was associated with larger HRs for depression, cognitive dysfunction, pain, opioid analgesics use, and sleep disorders (p-interaction <0.001 in each case). Limitations of the study include the potential for residual confounding by lifestyle factors and detection bias due to cancer survivors having greater healthcare contact. CONCLUSIONS: In this study, we observed that compared to women with no prior cancer, breast cancer survivors had higher risk of anxiety, depression, sleep problems, sexual dysfunction, fatigue, receipt of opioid analgesics, and pain. Relative risks estimates tended to decrease over time, but anxiety and depression were significantly increased for 2 and 4 years after breast cancer diagnosis, respectively, while associations for fatigue, pain, and sleep disorders were elevated for at least 5-10 years after diagnosis. Early diagnosis and increased awareness among patients, healthcare professionals, and policy makers are likely to be important to mitigate the impacts of these raised risks

Why Indonesia Adopted ‘Quiet Diplomacy’ over R2P in the Rohingya Crisis : The Roles of Islamic Humanitarianism, Civil–Military Relations, and ASEAN

Following atrocities against the minority Muslim Rohingya population by the Myanmar military, several states have imposed sanctions and deployed international justice strategies against the Myanmar government. In contrast, Indonesia has used an alternative ‘quiet diplomacy’ approach, focused on aid delivery to affected communities and cooperation with Myanmar. The paper presents one of the first empirical examinations of Indonesia’s role, and considers Indonesia’s approach from a realpolitik perspective to show why Indonesia has avoided R2P measures. The paper identifies three factors that shaped Indonesia’s approach: Islamic humanitarianism, Indonesia’s own experience of managing civil–military relations during a contested democratic transition, and its continued commitment to core ASEAN principles. The paper also contributes to wider debates by identifying some of the limitations of R2P, especially in terms of how R2P can be sidelined by national and regional diplomatic priorities, in this case manifested in the quiet diplomacy approach

Associations Between Breast Cancer Survivorship and Adverse Mental Health Outcomes: A Systematic Review.

Background: We aimed to systematically review the evidence on adverse mental health outcomes in breast cancer survivors (≥1 year) compared with women with no history of cancer. Methods: Studies were identified by searching MEDLINE, PsycINFO, the Cumulative Index to Nursing and Allied Health Literature, and the Social Sciences Citation Index, and through backward citation tracking. Two researchers selected the studies, extracted data, and assessed the risk of bias. Results: Sixty studies were included. Of 38 studies of depression, 33 observed more depression in breast cancer survivors; this was statistically significant in 19 studies overall, including six of seven where depression was ascertained clinically, three of four studies of antidepressants, and 13 of 31 that quantified depressive symptoms. Of 21 studies of anxiety, 17 observed more anxiety in breast cancer survivors, statistically significant in 11 studies overall, including two of four with clinical/prescription-based outcomes, and in eight of 17 of anxiety symptoms. Breast cancer survivors also had statistically significantly increased symptoms/frequency of neurocognitive dysfunction (18 of 24 studies), sexual dysfunctions (5 of 6 studies), sleep disturbance (5 of 5 studies), stress-related disorders/PTSD (2 of 3 studies), suicide (2 of 2 studies), somatisation (2 of 2 studies), and bipolar and obsessive-compulsive disorders (1 of 1 study each). Studies were heterogeneous in terms of participants' characteristics, time since diagnosis, ascertainment of outcomes, and measures reported. Approximately one-half of the studies were at high risk of selection bias and confounding by socio-economic status. Conclusions: There is compelling evidence of an increased risk of anxiety, depression and suicide, and neurocognitive and sexual dysfunctions in breast cancer survivors compared with women with no prior cancer. This information can be used to support evidence-based prevention and management strategies. Further population-based and longitudinal research would help to better characterize these associations

Quality of life and mental health in breast cancer survivors compared with non-cancer controls: a study of patient-reported outcomes in the United Kingdom.

PURPOSE: There is limited high-quality evidence on quality of life, anxiety, and depressive symptoms in breast cancer survivors and women with no history of cancer. We aimed to address this by comparing patient-reported outcomes between breast cancer survivors and women with no history of breast cancer. METHODS: Breast cancer survivors and women with no prior cancer were selected from the UK Clinical Practice Research Datalink GOLD primary care database, which includes population-based primary care electronic health record data. Breast cancer survivors and controls were frequency matched by age and primary care practice. Outcomes were assessed with validated instruments via postal questionnaire. Linear and logistic regression models were fitted to estimate adjusted associations between breast cancer survivorship and outcomes. RESULTS: A total of 356 breast cancer survivors (8.1 years post diagnosis) and 252 women with no prior cancer participated in the study. Compared with non-cancer controls, breast cancer survivors had poorer QoL in the domains of cognitive problems (adjusted β (aβ) = 1.4, p = 0.01), sexual function (aβ = 1.7, p = 0.02) and fatigue (aβ = 1.3, p = 0.01), but no difference in negative feelings, positive feelings, pain, or social avoidance. Breast cancer survivors had higher odds of borderline-probable anxiety (score ≥ 8) (adjusted OR = 1.47, 95%CI:1.15-1.87), but no differences in depression. Advanced stage at diagnosis and chemotherapy treatment were associated with poorer QoL. CONCLUSIONS: Compared with women with no history of cancer, breast cancer survivors report more problems with cognition, sexual function, fatigue, and anxiety, particularly where their cancer was advanced and/or treated with chemotherapy. IMPLICATIONS FOR CANCER SURVIVORS: Breast cancer survivors with more advanced disease and/or treated with chemotherapy should be closely monitored and, when possible, offered evidence-based intervention for fatigue, cognitive dysfunction, and sexual problems

Salivary cortisol response to infant distress in pregnant women with depressive symptoms.

The Hypothalamic-Pituitary-Adrenal (HPA) axis has been proposed as a potential underlying biological mechanism linking prenatal depression with adverse offspring outcomes. However, it is unknown whether the reactivity of this system to stress is altered in pregnant women experiencing depression. The objective of this study was to investigate whether salivary cortisol response to a distressed infant film is enhanced in pregnant women with symptoms of depression compared with non-depressed controls. Salivary cortisol and subjective mood responses to the film were measured in 53 primiparous women, between 11 and 18 weeks gestation. Both groups showed similar increases in state anxiety in response to the film, but there was a significantly increased cortisol response in women experiencing symptoms of depression. Depression during pregnancy is associated with increased reactivity of the HPA axis. This is consistent with altered HPA axis functioning being a key mechanism by which prenatal mood disturbance can impact upon fetal development

Short-term serotonergic but not noradrenergic antidepressant administration reduces attentional vigilance to threat in healthy volunteers

Anxiety is associated with threat-related biases in information processing such as heightened attentional vigilance to potential threat. Such biases are an important focus of psychological treatments for anxiety disorders. Selective serotonin reuptake inhibitors (SSRIs) are effective in the treatment of a range of anxiety disorders. The aim of this study was to assess the effect of an SSRI on the processing of threat in healthy volunteers. A selective noradrenergic reuptake inhibitor (SNRI), which is not generally used in the treatment of anxiety, was used as a contrast to assess the specificity of SSRI effects on threat processing. Forty-two healthy volunteers were randomly assigned to 7 d double-blind intervention with the SSRI citalopram (20 mg/d), the SNRI reboxetine (8 mg/d), or placebo. On the final day, attentional and interpretative bias to threat was assessed using the attentional probe and the homograph primed lexical decision tasks. Citalopram reduced attentional vigilance towards fearful faces but did not affect the interpretation of ambiguous homographs as threatening. Reboxetine had no significant effect on either of these measures. Citalopram reduces attentional orienting to threatening stimuli, which is potentially relevant to its clinical use in the treatment of anxiety disorders. This finding supports a growing literature suggesting that an important mechanism through which pharmacological agents may exert their effects on mood is by reversing the cognitive biases that characterize the disorders that they treat. Future studies are needed to clarify the neural mechanisms through which these effects on threat processing are mediated

Short Communications: First tracking of individual American Robins (Turdus migratorius) across seasons

The American Robin (Turdus migratorius) is one of the most widespread, common bird species in North America; yet, very little is known about its migratory connectivity, migration timing, and migratory routes. Using archival GPS tags, we tracked the movements of 7 individual robins from 3 breeding populations in the United States. Four robins captured in Denali National Park and Preserve, Alaska, overwintered in Texas, Nebraska, Oklahoma, and Montana, up to 4,500 km from the capture location. One robin captured in Amherst, Massachusetts, overwintered in South Carolina 1,210 km from the capture location, whereas 2 robins captured in Washington, D.C., spent the entire year within 6 km of their original capture location. Understanding the annual cycle and differences in migration strategies for a species that exhibits large regional variation in movement has the potential to provide novel insights into how conspecific populations respond to current and future heterogeneity in climate and habitat. The regionspecific patterns presented here suggest robins could serve as sentinels of environmental change at a continental scale

An improved competitive inhibition enzymatic immunoassay method for tetrodotoxin quantification

Quantifying tetrodotoxin (TTX) has been a challenge in both ecological and medical research due to the cost, time and training required of most quantification techniques. Here we present a modified Competitive Inhibition Enzymatic Immunoassay for the quantification of TTX, and to aid researchers in the optimization of this technique for widespread use with a high degree of accuracy and repeatability