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Hormone Status (hormone + status)
Selected AbstractsEffects of maternally transferred organochlorine contaminants on early life survival in a freshwater fishENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 10 2005Thomas A. Johnston Abstract Laboratory research has shown that female fish can pass toxic organochlorines (OCs) from their bodies to their eggs, killing their offspring if sufficient quantities are transferred. We conducted a controlled incubation study using gametes from a wild, OC-contaminated walleye (Sander vitreus) population (Bay of Quinte, Lake Ontario, Canada) in order to assess among-female variation in offspring early life survival in relation to ova concentrations of planar OCs (polychlorinated dibenzo- p -dioxins and furans and planar polychlorinated biphenyls) and a suite of other maternal and ova characteristics. Equal volumes of ova from each female were fertilized, pooled, and incubated together as an experimental cohort. Relative survival of each female's offspring was estimated as the proportion of surviving larvae (at ,5 d posthatch) that she contributed to the cohort as determined by microsatellite DNA parentage assignment. Total planar OC concentration (expressed as toxic equivalency of 2,3,7,8-tetrachloro-dibenzo- p -dioxin) of ova was positively related to maternal age and size and to ova lipid content. However, early life survival did not decline with increasing ova planar OC concentrations. Similarly, we observed no significant relationships between early life survival and ova thiamine content, ova fatty acid composition, or maternal age or size. Early life survival was more strongly correlated with date of spawn collection, thyroid hormone status of the ova, and ovum size. Maternally transferred planar OCs do not appear to negatively influence female reproductive success in this walleye population. [source] Assessing the joint effects of chlorinated dioxins, some pesticides and polychlorinated biphenyls on thyroid hormone status in Japanese breast-fed infantsENVIRONMETRICS, Issue 2 2003Takashi Yanagawa Abstract Joint effects of dioxin related chemicals (DXNs), hexachlorocyclohexanes (HCHs), DDT, dieldrin, heptachlor-epoxide (HCE), chlordane and polychlorinated biphenyls (PCB) on the levels of triirodothyronine (T3), thyroxine (T4), thyroid stimulating hormones (TSH) and thyroid binding globulin (TBG) in the peripheral blood of 101 breast-fed infants are studied. The statistical issue involved is how to estimate the effects based on data from volunteer subjects with possible measurement errors. A chain independent graph is applied for modeling the associations among factors, and dicotomizations of selected factors are performed for estimating the effects. Use of nonparametric methods with careful consideration of over-adjustment is suggested. It is shown that the estimated odds ratios of DXNs,DDT, the first principal component of DXNs and DDT, relative to TSH are 3.02 (p -value=0.03) and 7.15 (p -value=0.02), respectively, when PCB is not adjusted and adjusted for, respectively. Copyright © 2003 John Wiley & Sons, Ltd. [source] Protein Undernutrition-Induced Bone Loss Is Associated with Decreased IGF-I Levels and Estrogen DeficiencyJOURNAL OF BONE AND MINERAL RESEARCH, Issue 4 2000Patrick Ammann M.D. Abstract Protein undernutrition is a known factor in the pathogenesis of osteoporotic fracture in the elderly, but the mechanisms of bone loss resulting from this deficiency are still poorly understood. We investigated the effects of four isocaloric diets with varying levels of protein content (15, 7.5, 5, and 2.5% casein) on areal bone mineral density (BMD), bone ultimate strength, histomorphometry, biochemical markers of bone remodeling, plasma IGF-I, and sex hormone status in adult female rats. After 16 weeks on a 2.5% casein diet, BMD was significantly decreased at skeletal sites containing trabecular or cortical bone. Plasma IGF-I was decreased by 29,34% and no estrus sign in vaginal smear was observed. To investigate the roles of estrogen deficiency and protein undernutrition, the same protocol was used in ovariectomized (OVX) or sham-operated (SHAM) rats, pair-fed isocaloric diets containing either 15 or 2.5% casein. Trabecular BMD was decreased by either manipulation, with effects appearing to be additive. Cortical BMD was decreased only in rats on a low-protein diet. This was accompanied by an increased urinary deoxypyridinoline excretion without any change in osteocalcin levels, suggesting an uncoupling between resorption and formation. Isocaloric protein undernutrition decreased bone mineral mass and strength. This effect might be related to decreased plasma IGF-I and/or estrogen deficiency with a consequent imbalance in bone remodeling. [source] Sex Differences in Oestrogen-Induced p44/42 MAPK Phosphorylation in the Mouse Brain In VivoJOURNAL OF NEUROENDOCRINOLOGY, Issue 8 2006K. Barabás In addition to the classical direct genomic mechanisms of action, oestrogen also exerts poorly understood, nonclassical effects on the signalling system in neurones. In the present study, we investigated whether sex differences exist in gonadectomy- and oestrogen-induced effects on p44/42 mitogen-activated protein kinase (MAPK) phosphorylation in specific brain regions of mice. We demonstrate that MAPK immunoreactivity was not altered by gonadectomy or oestrogen treatment in either sex. However, we show that the level of phosphorylated MAPK (pMAPK) within the anteroventral periventricular nucleus (AVPV) was consistently higher in males than females irrespective of gonadal steroid hormone status. In addition, gonadectomy was found to decrease pMAPK immunoreactivity within the piriform cortex of males. Oestrogen increased pMAPK immunoreactivity in the medial preoptic area and AVPV of females, but failed to have the same effect in male mice. Overall, these results demonstrate a marked sex difference in oestrogen-induced alteration of MAPK phosphorylation in the brain in vivo. [source] Pituitary disease , perspectives of patients and partnersJOURNAL OF NURSING AND HEALTHCARE OF CHRONIC ILLNE SS: AN INTERNATIONAL INTERDISCIPLINARY JOURNAL, Issue 2 2009FRCNA, Trisha Dunning AM Aim. To explore experiences of pituitary disease of people with pituitary disease (PD) and their partners (PT). Background. Pituitary disease encompasses a range of hormonal abnormalities that produce a variety of signs and symptoms depending on the underlying cause. Design. A triangulated exploratory study. Methods. The study was conducted in three phases: (a) non-participant monitoring of an Internet pituitary chat room over four months; (b) in-depth structured interviews with PD attending a pituitary outpatient clinic (n = 8) and PT (n = 6), (c) focus groups (n = 12). Data were collected in 2005. Results. Four themes emerged from the discussion in each phase: ,need to be normal', ,emotional merry-go-round', ,damage to the self', and ,doctor ignorance'. Symptoms of pituitary disease were often mistaken for sinusitis, ,getting old before my time', hypochondria, stress, and ,something sinister changing the way I look'. Time to diagnosis varied from four weeks to 15 years. PD felt included in decision-making but partners relied on PD for information. Body image changes were significant making PD feel like a ,freak show for medical students' and the emotional distress persisted after treatment and ,cure'. The word ,tumour' caused significant stress and anxiety and depression was common. PD and PT felt general practitioners (GP) lacked information about pituitary disease. Conclusions. Pituitary disease has a major impact on psychological well-being. PD but not PT felt involved in decisions about their management. GPs may need more education about pituitary disease. The study adds important information about the emotional effects of pituitary disease and its treatment. Relevance to clinical practice. Pituitary disease is a generic term encompassing a range of underlying disease processes that often produce vague symptoms, often attributed to other causes, which delays diagnosis and treatment. Pituitary disease has a significant under recognised impact on people's mental and physical wellbeing and self-concept. Although the underlying hormonal imbalances associated with pituitary disease are largely reversible (cured), emotional distress persists. Regular monitoring of emotional wellbeing as well as medical and hormone status is warranted. [source] Intracranial germinoma: A rare but important differential diagnosis in children with growth retardationACTA PAEDIATRICA, Issue 3 2006Sven Gottschling Abstract Aim: Intracranial germinoma is a rare malignant tumour in childhood with an excellent prognosis under adequate therapy. Finding the right diagnosis at an early stage is difficult because of the slow-growing tumour and the resulting lack of clinical symptoms. Methods: Our patients with histologically secured germinoma were retrospectively assessed concerning growth retardation, pituitary hormone status, magnetic resonance imaging scan results and clinical symptoms to find out whether there is a leading parameter. Results: In all our patients, the leading symptom was growth retardation of at least 2 y before being diagnosed. Conclusion: Growth retardation seems to be a very early sign of germinoma in the suprasellar region. Therefore, early neuroradiological imaging combined with pituitary hormone status should be considered in every paediatric patient with a history of secondary growth retardation. [source] | ||||||||||