Search PubMed⌕ Search

Biomedical subjects

L Dye

Publications and source records attributed to L Dye.

17 recordsLinked to original sources
PubMed2006

Effect of creatine supplementation and sleep deprivation, with mild exercise, on cognitive and psychomotor performance, mood state, and plasma concentrations of catecholamines and cortisol.

RATIONALE: Sleep deprivation has a negative effect on cognitive and psychomotor performance and mood state, partially due to decreases in creatine levels in the brain. Therefore, creatine supplementation should lessen the negative effects of sleep deprivation. OBJECTIVES: The objective of this study was to examine the effect of creatine supplementation and sleep deprivation, with mild exercise, on cognitive and psychomotor performance, mood state, and plasma concentrations of catecholamines and cortisol. METHOD: Subjects were divided into a creatine group (n=10) and a placebo group (n=9). They took 5 g of creatine monohydrate or a placebo, dependent on their group, four times a time a day for 7 days, immediately prior to the experiment. The study was double blind. Subjects undertook tests of random movement generation (RMG), verbal and spatial recall, choice reaction time, static balance and mood state pre-test (0 h), after 6, 12 and 24 h of sleep deprivation, with intermittent exercise. They were tested for plasma concentrations of catecholamines and cortisol at 0 and 24 h. RESULTS: At 24 h, the creatine group demonstrated significantly less change in performance from 0 h (delta) in RMG, choice reaction time, balance and mood state. There were no significant differences between groups in plasma concentrations of catecholamines and cortisol. Norepinephrine and dopamine concentrations were significantly higher at 24 h than 0 h, but cortisol were lower. CONCLUSIONS: Following 24-h sleep deprivation, creatine supplementation had a positive effect on mood state and tasks that place a heavy stress on the prefrontal cortex.

Adult↗
PubMed2006

Modest changes in dietary intake across the menstrual cycle: implications for food intake research.

Food intake varies across the menstrual cycle in mammals, energy intake usually being greater in the premenstrual phase compared with the postmenstrual phase. Premenstrual increments in energy intake and a preferential selection of carbohydrate have been suggested to be greater in women with premenstrual syndrome (PMS), who may be more sensitive to cyclical hormonal or neurotransmitter fluctuations. This has direct implications for research within populations of women, especially where the primary outcome is diet or a change in energy balance. We aimed to determine whether: the premenstrual intake of energy and macronutrients differed from the postmenstrual intake; the change in intake across the menstrual cycle differed in women with PMS compared with controls; and the change in intake was related to the severity of premenstrual symptoms. We collected 3 d dietary intake data during the postmenstrual and premenstrual phases of the menstrual cycle in thirty-one women with PMS and twenty-seven control women. The consumption of energy and macronutrient intake were similar between the phases of the cycle in women with PMS. Conversely, intakes were usually greater premenstrually in control women, although not all differences were statistically significant. Exceptions were with non-milk extrinsic sugars and alcohol, which were both consumed in greater amounts in the premenstrual phase in women with PMS. Significant correlations were observed between the severity of symptoms and the change in the consumption of these nutrients. These data suggest that a consideration of the menstrual cycle phase and PMS in diet may not be warranted, especially in cross-sectional analysis, although it may need to be taken into account when examining change in intake during dietary interventions.

Adolescent↗
PubMed2006

The effect of dermatology consultations in secondary care on treatment outcome and quality of life in new adult patients with atopic dermatitis.

BACKGROUND: The prevalence of atopic dermatitis (AD) is increasing worldwide, and many patients present to secondary care in adult life. This is a significant contribution to the workload of all dermatology departments. There are no studies investigating the impact of a dermatology consultation within secondary care. OBJECTIVES: To examine the effect of dermatology consultations in secondary care on treatment outcome and quality of life in new adult patients with AD. METHODS: This prospective observational study recruited new adult patients with AD referred from primary care. Eczema severity was assessed using the SCORAD (Severity Scoring of AD) index and subjective good or poor clinical outcome. The Dermatology Life Quality Index (DLQI) was used to quantify the impact of AD on adult patients. Patients were assessed at initial consultation (T1), 6 weeks (T2) and 3 months (T3). Statistical analysis was performed using independent t-tests, repeated-measures analysis of variance, correlation coefficients and Bonferroni post hoc comparisons. RESULTS: Sixty-three patients were recruited (37 women, 26 men) with a mean age of 34 years. Mean SCORAD at T1 was 48.2 and the majority (51%) had severe eczema (objective SCORAD>40). Mean SCORAD reduced by 52% from T1 to T2 (P<0.001) but there was no significant change in SCORAD from T2 to T3. A subjective good clinical outcome was validated by a decrease in SCORAD of >20 (P<0.001). Patients in the good clinical outcome group were significantly older than those in the poor clinical outcome group (38 vs. 27 years, P<0.05). The mean age at presentation of women was significantly younger than men (29 vs. 43 years, P<0.01). Women's mean SCORAD improved over all three visits, while men's mean SCORAD improved from T1 to T2 but worsened from T2 to T3 (P<0.001). The mean DLQI reduced over all three visits, from 9.5 at T1 to 8.8 at T2 and 7.0 at T3, and was significantly correlated with SCORAD at T1 and T2 (P<0.01). Patients accurately self-scored their eczema on a body map as shown by a significant correlation between these scores and SCORAD at T1 and T2 (P<0.001). CONCLUSIONS: We have shown that within the first 3 months of referral to secondary care, new adult patients with AD have the greatest improvement in AD, measured by SCORAD, after their initial appointment. Quality of life, as measured by DLQI, continued to improve over all three visits.

Adolescent↗
PubMed2006

Menstrual cycle symptoms are associated with changes in low-grade inflammation.

BACKGROUND: A close link between mood, low-grade inflammation and obesity has been demonstrated even in healthy subjects. We investigated the relationship between changes in physical and psychological symptoms and inflammatory markers during the menstrual cycle both in normal weight and in overweight women. MATERIALS AND METHODS: Eight healthy normal weight (body mass index 21.6 +/- 1.9 kg m(-2)) and seven overweight (body mass index 30 +/- 2.4 kg m(-2)) young women with normal ovarian function and with no premenstrual syndrome were assessed 15 times throughout their menstrual cycle. At each time point fasting blood was drawn and symptoms were recorded using the Freeman Daily Symptom Record. RESULTS: Independent of weight status, the serum concentrations of highly sensitive C-reactive protein (hs-CRP) and the total scores, in addition to the individual four factors (mood, behaviour, pain and physical symptoms), of the Daily Symptom Record varied significantly during the menstrual cycle (all P < or = 0.04) and paralleled each other. During the menstrual cycle, repeated hs-CRP serum concentrations correlated to the corresponding total symptom score and the factors mood, behaviour and physical symptoms, independent of both weight status and changes in circulating gonadal steroids (all P < or = 0.04). These associations were not observed for tumour necrosis factor-alpha serum levels. The mean hs-CRP concentrations were associated with the mean total symptom score, independent of weight status (r = 0.56, P = 0.04). CONCLUSION: Healthy young women showed psychological and physical symptoms during the menstrual cycle which changed in association with alterations in low-grade inflammation and which were independent of body weight or plasma levels of gonadal steroids.

Adult↗
PubMed2005

Effect of consumption of soy isoflavones on behavioural, somatic and affective symptoms in women with premenstrual syndrome.

Up to 80 % of the Western female population experience premenstrual syndrome (PMS). Long-term pharmacological therapy is unacceptable to most women, and is not warranted for moderate symptoms. Nutritional therapies are popular, but lack a clear evidence base. Anecdotal evidence suggests beneficial effects of soy isoflavones because of their influence on endogenous oestrogen and actions on specific tissues. The effect of isolated soya protein (ISP) containing 68 mg/d (aglycone equivalents) soy isoflavones (IF) on premenstrual symptom severity was studied in a seven-menstrual cycle, double-blind, placebo-controlled, crossover intervention study in twenty-three women with prospectively confirmed PMS aged 18-35 years and BMI 19-30 kg/m(2). ISP containing IF or milk protein placebo was consumed for two complete menstrual cycles. ISP containing IF (genistein, daidzein, equol) were measured in 24 h urine samples. After two cycles of ISP containing IF intervention, total symptoms (F(2,36) 8.20, P=0.000) and physical symptoms (F(2,36) 8.18, P=0.000) were significantly reduced compared with baseline after both active and placebo treatments, although differences between active and placebo treatment were non-significant. Specific premenstrual symptoms, headache (F(2,32) 4.10, P=0.026) and breast tenderness (F(2,32) 4.59, P=0.018), were reduced from baseline after soy IF, but not milk protein placebo. Cramps (F(2,32) 4.15, P=0.025) and swelling (F(2,32) 4.64, P=0.017) were significantly lower after active treatment compared with placebo. Concentrations of genistein and daidzein were increased following soy IF consumption, but equol production did not enhance symptom reduction. The present study showed that ISP containing IF may have potential to reduce specific premenstrual symptoms via non-classical actions.

Adolescent↗
PubMed2003

Weight development over time in parous women--the SPAWN study--15 years follow-up.

BACKGROUND: Weight gain is common after pregnancy. Most studies suggest that weight gain associated with a pregnancy is between 0.5 and 3.8 kg up to 2.5 y of follow-up. However, 73% of the female patients at our obesity clinic identified pregnancy as an important trigger for marked weight retention. The majority retained more than 10 kg after each pregnancy. The aim of this study was to examine long-term weight development after pregnancy in a 15 y follow-up of women who took part in the Stockholm Pregnancy And Women's Nutrition (SPAWN) study. METHOD AND SUBJECTS: The SPAWN study is a long-term follow-up study of women who delivered children in 1984-85 in Stockholm (n=2342). A total of 1423 participants (response rate=61%) completed questionnaires, which covered eating behaviour and exercise, demographic information including social situation and status and details of the pregnancy before, during and up to 1 y after pregnancy. After 15 y, these women were invited to take part in the follow-up study. Anthropometric measurements and the same questionnaire data were collected from the 563 women who participated (response rate=40%). The sample was divided into two main groups: those who were normal weight before pregnancy and remained normal weight, and those who were normal weight before pregnancy and had become overweight at 15 y follow-up. RESULTS: Those women who became overweight had a higher pre-pregnant body mass index (BMI) (22.3+/-1.5 vs 20.5+/-1.6 kg/m(2), P<0.001), gained more weight during pregnancy (16.3+/-4.3 vs 13.6+/-3.7 kg, P<0.001) and had retained more at 1 y follow-up. The women who became overweight had a steeper weight trajectory gaining more from 1 y follow-up to 15 y follow-up (11.1+/-6.5 vs 4.5+/-6.5 kg, P<0.001), with a higher BMI at 15 y follow-up of 27.5+/-2.6 vs 22.5+/-2.3 5 kg/m(2) (P<0.001). However, differences between those who became overweight and those who did not could not be explained by age, number of children and various socioeconomic factors. Features of pregnancy that did differ between the two groups were breastfeeding and smoking cessation. However, women who became overweight had lower lactation scores than women who remained normal weight. Relatively more subjects of the group that became overweight stopped smoking during pregnancy. DISCUSSION: Pregnancy is a vulnerability factor for some women to become overweight. This study attempted to identify those factors that place initially normal weight women on a steeper weight trajectory as a result of pregnancy. Demographic, behavioural, physical and psychological characteristics only partly explain the weight gain observed at 15 y follow-up. Further research is required to investigate the relative role of these characteristics in predicting postpregnancy weight development.

Adult↗
PubMed2002

Nutrition and brain function: a multidisciplinary virtual symposium.

A few months ago, the Brazilian Society for Neuroscience and Behavior (SBNeC) promoted a "virtual symposium" (by Internet, under the coordination of R.C.A. Guedes) on "Nutrition and Brain Function". The discussions generated during that symposium originated the present text, which analyzes current topics on the theme, based on the multidisciplinary experience of the authors. The way the brain could be non-homogeneously affected by nutritional alterations, as well as questions like early malnutrition and the development of late obesity and hormone abnormalities were discussed. Also, topics like the role of essential fatty acids (EFAs) on brain development, increased seizure susceptibility and changes in different neurotransmitters and in cognitive performance in malnourished animals, as well as differences between overall changes in nutrient intake and excess or deficiency of specific nutrients (e.g. iodine deficiency) were analyzed. It was pointed out that different types of neurons, possibly in distinct brain structures, might be differently affected by nutritional manipulation, including not only lack-but also excess of nutrient intake. Such differences could help in explaining discrepancies between data on humans and in animals and so, could aid in determining the basic mechanisms underlying lesions or changes in brain function and behavior.

Brain↗
PubMed2001

A novel technique to demonstrate disturbed appetite profiles in haemodialysis patients.

BACKGROUND: Malnutrition is common among dialysis patients and is associated with an adverse outcome. One cause of this is a persistent reduction in nutrient intake, suggesting an abnormality of appetite regulation. METHODS: We used a novel technique to describe the appetite profile in 46 haemodialysis (HD) patients and 40 healthy controls. The Electronic Appetite Rating System (EARS) employs a palmtop computer to collect hourly ratings of motivation to eat and mood. We collected data on hunger, desire to eat, fullness, and tiredness. HD subjects were monitored on the dialysis day and the interdialytic day. Controls were monitored for 1 or 2 days. RESULTS: Temporal profiles of motivation to eat for the controls were similar on both days. Temporal profiles of motivation to eat for the HD group were lower on the dialysis day. Mean HD scores were not significantly different from controls. Dietary records indicated that dialysis patients consumed less food than controls. CONCLUSIONS: Our data indicate that the EARS can be used to monitor subjective appetite states continuously in a group of HD patients. A HD session reduces hunger and desire to eat. Patients feel more tired after dialysis. This does not correlate with their hunger score, but does correlate with their fullness rating. Nutrient intake is reduced, suggesting a resetting of appetite control for the HD group. The EARS may be useful for intervention studies.

Adult↗
PubMed2000

Macronutrients and mental performance.

There is currently intense interest in the effects of macronutrients on psychological states, mental performance, and well-being. A strong theoretical perspective has guided work on carbohydrates and their relation to brain serotoninergic function with concomitant effects on performance. The clearest and most reliable effects have been observed for the beneficial action of glucose on cognitive performance, supported by investigations of hypoglycemia, which is associated with general impairment of cognitive performance. The effects of complex carbohydrates are less distinct and change with time of day; e.g., carbohydrate at breakfast tends to improve morning performance. However, these studies are rarely decisive. Far fewer experiments have been performed on protein and fat, and it is difficult to draw any firm conclusions. Macronutrients are seldom given alone, proportions of protein and fat differ greatly between studies, and comparisons are frequently performed with no food at all. Food intake may mitigate the effects of low doses but not of high doses of alcohol on performance. Effects of macronutrients on cognitive performance may be dependent on their effects on glucose metabolism, metabolic activation, or serotonin. Other factors that modify effects include time of day, circadian rhythms, type of task, habitual diet, and vulnerability of the population.

Alcohol Drinking↗
PubMed2000

From the outside looking in. The surgical approach.

This series of articles will draw on Physiology and Anatomy, a homeostatic approach (hereafter referred to as 'the reader'), written by John Clancy and Andrew McVicar. There will also be cross-references to the series of articles entitled 'Homeostasis--the key concept to physiological control' published in the British Journal of Theatre Nursing 1996-98. The articles will include some activities which the readers can carry out to test their understanding and deepen their knowledge base of the anatomy explored in each article. The introductory article will cover the common anatomical structures involved in the 'surgical approach', looking first at the anatomy and then relating it to surgical practice. Homeostasis is the key underlying principle to which the surgical practice will refer.

Dermatologic Surgical Procedures↗
PubMed1998

The assessment of menstrual synchrony: comment on Weller and Weller (1997)

A. Weller and L. Weller (1997) claimed to report "the definitive study of menstrual synchrony" (p. 148). To allow for cycle variability, they used the following criterion for synchrony: It occurred in 2 out of 3 months. The underlying assumption of the state of menstrual synchrony is that cycle length variability is minimal. The present article uses a random selection of cycle lengths from a distribution described by R. F. Vollman (1977) to illustrate how variable cycle lengths cause a fluctuation from synchrony to a synchrony. A. Weller and L. Weller's (1997) study is not, therefore, conclusive, and future studies of menstrual synchrony should include an assessment of cycle variability as well as onset difference.

Female↗
PubMed1998

Infection of human primary renal epithelial cells with HIV-1 from children with HIV-associated nephropathy.

Children affected with human immunodefficiency virus (HIV)-associated nephropathy (HIVAN) usually develop significant renal glomerular and tubular epithelial cell injury. The pathogenesis of these changes is not clearly understood. Human renal tubular epithelial cells (RTEc) do not express CD4 surface receptors, and it is not clear whether these cells can be infected by HIV-1. Certain strains of HIV-1, however, have been shown capable of infecting CD4-negative epithelial cell lines. We hypothesized that the inability of laboratory strains of HIV-1 to infect renal epithelial cells may be due to a limited tropism, as opposed to wild-type viruses derived from children with HIVAN, and that viruses derived from these children are capable of infecting RTEc from the same patient. Here, we have demonstrated that HIV-1 isolates from children with HIVAN can productively infect RTEc through a CD4 independent pathway, and that infected mononuclear cells can transfer the virus to human RTEc. Human RTEc sustained low levels of viral replication and HIV-1 inhibited the growth and survival of cultured human RTEc. Thus, HIV-1 may directly induce degenerative changes in RTEc of children with HIVAN. Infected macrophages may play a relevant role in this process by transferring viruses to RTEc.

AIDS-Associated Nephropathy↗
PubMed1998

Functional food science and behaviour and psychological functions.

The impact of ingesting various foods on psychological and behavioural functions is a topic of both interest and concern to the general public. In this article, the scientific literature concerning demonstrated cause-and-effect relationships is reviewed, beginning with methodological considerations specific to the quantification of particular behaviours and psychological events. The essential function of food is to satisfy hunger and the need for essential nutrients. The contributions of macronutrients to appetite and satiety are described, as well as their impact on metabolism and energy balance. Functional properties of macronutrient substitutes (high-intensity sweeteners, fat replacers) and flavour enhancers are examined in relation to their contribution to hunger, satiety, and energy balance. The effects of foods and individual nutrients on the performance of diverse psychomotor tasks are studied with consideration given to the various validated quantitative tools used to assess behaviour. The effects of food components on activation, sedation, and affective states such as dysphoria are also reviewed, with special attention given to brain function and neuroactive substances such as serotonin and the endorphins. The case of hyperactivity in children is given special emphasis with reference to the potential influence of sugar and food additives. Safety issues related to food constituents and additives are discussed. Finally, a set of criteria is proposed for the evaluation and elaboration of studies in the behavioural and psychological fields, along with suggestions for future research.

Affect↗
PubMed1997

Menstrual cycle and appetite control: implications for weight regulation.

Hormonal fluctuations associated with the menstrual cycle influence appetite control and eating behaviour. Energy intake varies during the reproductive cycle in humans and animals, with a periovulatory nadir and a luteal phase peak. Patterns of macronutrient selection show less consistency but a number of studies report carbohydrate cravings in the premenstrual phase, particularly in women with premenstrual syndrome. The cyclical nature of food cravings are frequently, but not invariably, associated with depression. Fluctuations in appetite, cravings and energy intake during the menstrual cycle may occur in parallel with cyclical rhythms in serotonin, which can be accompanied by affective symptoms. The premenstrual phase can be considered as a time when women are especially vulnerable to overconsumption, food craving and depression; this is often associated with low serotonin activity.

Affect↗
PubMed1995

Food craving during the menstrual cycle and its relationship to stress, happiness of relationship and depression; a preliminary enquiry.

The associations between retrospective ratings of food craving and depression during the premenstrual, menstrual and postmenstrual phases of the preceding menstrual cycle and ratings of current levels of stress and happiness of relationship were examined in 5,546 women. In each phase examined, the severity of food craving was very strongly related to the reported severity of depression. Overall levels of food craving were inversely related to happiness of relationship and there was some interaction of this effect with on-going stress. However, once the effect of depression was accounted for there was no effect of either current stress or happiness of relationship on the cycle-related pattern of food craving and in general the magnitude of the effect of these psychosocial variables was very small compared with that of depression. Food cravings were also reported in the absence of depression, tending to show a cycle-related pattern, maximal premenstrually, declining during menstruation and further postmenstrually. Whilst this is consistent with a cycle-related biological explanation, it remains unclear whether the striking amplification of food craving ratings in association with co-existing depression, in all three phases examined, is also biologically based or dependent on psychological mechanisms. In view of the retrospective nature of the ratings of mood and craving and the limited assessment of stress and happiness of relationship, these findings should be regarded as preliminary. They are, however, of potential importance and the association between these two common phenomena deserves further study.

Adult↗