Biomedical subjects

Joey Kaye

Publications and source records attributed to Joey Kaye.

4 recordsLinked to original sources

PubMed2006

The four-dimensional stress test: psychological, sympathetic-adrenal-medullary, parasympathetic and hypothalamic-pituitary-adrenal responses following inhalation of 35% CO2.

BACKGROUND: Hypercapnia is a threat to homeostasis and results in neuroendocrine, autonomic and anxiogenic responses. The inhalation of carbon dioxide (CO2) may, therefore, provide a good paradigm for exploring the pathways by which stress can lead to increased susceptibility to ill-health through physiological and psychological stress reactivity. The current study was designed, therefore, to assess the psychological and physiological responses to the inhalation of CO2. METHODS: Healthy participants (N = 24) inhaled a single vital capacity breath of a mixture of CO2 (35%) and oxygen (65%). Blood pressure and heart rate were recorded for 5 min before and after the test and blood and saliva samples were taken immediately before and 2, 10, 20 and 30 min post-inhalation for the measurement of noradrenaline, salivary and serum cortisol and salivary alpha amylase. In addition, psychosomatic symptoms were recorded immediately before and after the test. The same protocol was repeated 4-6 weeks later at the same time of day. RESULTS: A single inhalation of CO2 increased blood pressure, noradrenaline, salivary alpha amylase and psychosomatic symptoms, but decreased heart rate at both testing sessions. Analyses of salivary cortisol data revealed that 70% of the sample could be reliably classified as either responders (i.e. demonstrated a post-CO2 cortisol increase) or non-responders (i.e. responded with a decrease or no change in cortisol following CO2) at both test sessions. Responders also perceived the test to be more aversive than non-responders. CONCLUSIONS: Inhalation of 35% CO2 reliably stimulated the key mechanisms involved in the human stress response. The inter-individual differences in the reactivity of the hypothalamic-pituitary-adrenal axis were also related to differences in the perception of the test.

Administration, Inhalation↗

PubMed2006

Investigations of thyroid hormones and antibodies based on a community health survey: the Busselton thyroid study.

OBJECTIVE: Overt or subclinical thyroid dysfunction is common within the community, yet the significance of subtle anomalies in thyroid function tests remains contentious. The aims of this study were to: (a) establish reference intervals for serum-free thyroxine (FT4), thyroid-stimulating hormone (TSH) and thyroid antibodies (antithyroperoxidase, TPOAb and antithyroglobulin, TgAb) in the Busselton community of south-western Western Australia; and (b) determine the prevalence of thyroid hormone anomalies in this community. SUBJECTS AND DESIGN: In 1981, 2115 adults residing in Busselton participated in a cross-sectional health survey that involved blood collection and a questionnaire on lifestyle and general health history. MEASUREMENTS: Serum samples were analysed for FT4, TSH, TPOAb and TgAb by immunochemiluminescent assays. RESULTS: Based on standard statistical approaches and using guidelines recommended by the National Academy of Clinical Biochemistry (NACB), reference intervals were derived for each analyte: 9-23 pmol/l for FT4, 0.4-4.0 mIU/l (TSH), < 35 KIU/l (TPOAb) and < 55 KIU/l (TgAb). The prevalence of elevated thyroid antibodies was 12.4% among subjects without a history of thyroid disease and is more common in women than in men. Elevated thyroid antibody levels were observed at both extremes of TSH abnormality, but were more commonly increased when TSH levels were above 4.0 mIU/l (63% subjects) than for those with TSH levels 0.4-4.0 mIU/l (7.8% subjects). CONCLUSIONS: This study establishes the prevalence of antibodies to thyroperoxidase and thyroglobulin in a community-based sample and reference intervals for free T4 and TSH. When the NACB decision limits are applied to older men or women, there is a markedly increased number with 'elevated' autoantibody levels compared to sex- and age-specific reference intervals.

Adolescent↗

PubMed2004

Responses to the 35% CO challenge in postpartum women.

Lactation has been associated with suppression of some components of the neuroendocrine stress response. In humans, suppression of the hypothalamo-pituitary-adrenal (HPA) axis has been demonstrated in response to both a psychological and an exercise challenge, but appears to be limited to a short period of time following suckling. Information regarding other components of the stress response and to other challenges in humans is limited. We have evaluated the endocrine, autonomic and psychological response to a single breath of 35% CO(2) during lactation. The 35% CO(2) challenge is a safe and simple test that has been shown to stimulate the HPA axis, produce autonomic activation and emotional arousal. Eight breastfeeding and six bottle-feeding mothers, 6 weeks' postpartum, and eight control women were studied. Twenty minutes following the cessation of feeding, plasma cortisol levels were significantly reduced in the breastfeeding women (P = 0.002 compared with control and P = 0.003 compared with bottle-feeders). Despite this, cortisol, blood pressure, heart rate and psychological responses to the challenge were no different in the breastfeeding group compared to either the control or bottle feeding groups. These results confirm that suckling is associated with short-term suppression of cortisol, but this has no effect on the ability of the mother to mount a normal hormonal, autonomic and psychological response to the 35% CO(2) challenge.

Adult↗

PubMed2003

Erdheim-Chester disease.

A 38-year-old man presented with numerous dermal nodules, similar to xanthoma disseminatum, that were histologically consistent with his diagnosis of Erdheim-Chester disease, a non-Langerhans cell histiocytosis. Other cutaneous manifestations of this disease include eyelid xanthelasma, pretibial dermopathy and pigmented lesions of the lips and buccal mucosa. The histological diagnosis of Erdheim-Chester disease was originally made on the patient's retroperitoneal tissue, obtained at a laparotomy for surgical treatment of a presumed phaeochromocytoma, and confirmed by the pathognomonic long bone X-ray findings of this disease.

Adult↗