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101.
The hypothalamo-pituitary-adrenal (HPA) system is a most important mediator of the organism's response to stress. Secretory activity of this endocrine system displays a specific regulation during normal nocturnal sleep in humans. Pituitary release of adrenocorticotropin (ACTH) as well as adrenocortical release of cortisol decreases to a minimum during early sleep which is simultaneously characterized by maximum release of growth hormone (GH) and a predominance of slow wave sleep (SWS). In contrast, release of ACTH and cortisol reaches a maximum during late sleep which is simultaneously characterized by minimum plasma concentrations of GH and a predominance of rapid eye movement (REM) sleep. The nadir activity of the pituitary-adrenal system during early sleep reflects an active inhibition of this 'stress' system. One of the factors mediating this inhibition presumably is the sleep associated hypothalamic secretion of a release inhibiting factor of ACTH. In addition, limbic-hippocampal neuronal networks contribute to the inhibitory control over HPA activity during early sleep. Those structures appear to coordinate HPA inhibition and cortical activity (with prevalent SWS) during early sleep, thereby facilitating the formation of memories in sleep. As indicated by studies testing the effects of elevated plasma glucocorticoid levels, the inhibition of HPA activity during early sleep is an essential prerequisite for the memory function of sleep. Possibly, immunological memory formation likewise benefits from this inhibition. The suppression of pituitary-adrenal secretory activity during early sleep can be significantly weakened after profound acute stress as well as in states of chronic stress (including normal aging) which thereby disturb regular memory formation in sleep. 相似文献
102.
Circulating procalcitonin and cleavage products in septicaemia compared with medullary thyroid carcinoma 总被引:1,自引:0,他引:1
Ittner L Born W Rau B Steinbach G Fischer JA 《European journal of endocrinology / European Federation of Endocrine Societies》2002,147(6):727-731
OBJECTIVE: Raised plasma levels of procalcitonin (proCT) represent an early marker for septicaemia. They are related to disease severity and inversely to outcome and response to treatment. ProCT is presumably synthesised in tIssues other than the thyroid C-cells which are the source of calcitonin (CT) in normal physiology. This study compares proCT and its cleavage products in the serum of patients with septicaemia with those in medullary thyroid carcinoma (MTC). METHODS: Immunoreactive proCT and its cleavage products were extracted from the serum of patients with septicaemia or MTC using octadecylsilyl silica columns and characterised by reversed phase HPLC and Western blot analysis. ProCT, CT(1-32) and the flanking peptides PAS-57 and PDN-21 were recognised with antibodies specific for the individual peptides. RESULTS: ProCT and a 10 kDa polypeptide were recognised with antibodies to PAS-57, CT(1-32) and PDN-21. An 8 kDa proCT fragment was detected with antibodies to CT and PDN-21. However, intact CT(1-32), PAS-57 and PDN-21, found in the serum of MTC patients, were undetectable. The results indicate partial cleavage of proCT in septicaemia different from that in MTC patients. CONCLUSIONS: ProCT and 10 and 8 kDa proCT fragments were recognised in the circulation of septic patients. They were different from the known proCT-processing products PAS-57, CT(1-32) and PDN-21 identified in the serum of normal subjects and of MTC patients. Distinct cleavage of proCT may contribute to the symptoms of septicaemia. 相似文献
103.
104.
Lange T Marshall L Späth-Schwalbe E Fehm HL Born J 《Brain, behavior, and immunity》2002,16(6):663-674
A somnogenic function is suspected for various cytokines. Foregoing experiments in humans indicated a selective increase in the production of interleukin-2 (IL-2) during sleep as compared with nocturnal wakefulness. Here, we examined whether conversely, IL-2 exerts a promoting influence on sleep. Also, the effects of IL-2 administered at ultra-low doses on systemic immune and endocrine parameters were assessed. Eighteen healthy men participated in three night sessions, receiving subcutaneously at 19:00 h either placebo or recombinant human IL-2 at doses of 1000 and 10,000 IU/kg bw. Polysomnographical recordings were obtained between 23:00 and 07:00 h. Blood was collected repeatedly to determine (i) white blood cell (WBC) counts including the enumeration of monocytes, natural killer (NK) cells, and lymphocyte subsets, (ii) serum concentrations of IL-2, soluble IL-2 receptor (sIL-2r), IL-4, IL-6, and interferon-gamma (IFN-gamma), and (iii) concentrations of adrenocorticotropin (ACTH), cortisol, thyreotropin (TSH), and growth hormone (GH). Changes after 1000 IU/kg bw IL-2 generally remained non-significant. However, distinct effects occurred after 10,000 IU/kg bw IL-2, inducing serum IL-2 concentrations selectively activating the high affinity IL-2 receptor. At this dose, IL-2 reduced the number of circulating lymphocytes (including all major subtypes) and NK cells, while counts of monocytes and neutrophils were increased. IL-4 release was stimulated and IFN-gamma concentration reduced after IL-2. Also, IL-2 increased the TSH concentration. There were no hints at a sleep promoting effect of IL-2. Immune changes suggest that nocturnal IL-2 administration induces a shift towards Th2 mediated defense. 相似文献
105.
106.
Socin HV Born J Wallemacq C Betea D Legros JJ Beckers A 《Clinical neurology and neurosurgery》2002,104(4):367-370
Colloid cysts of the third ventricle are rare, benign cysts of endodermal origin. Between 1989 and 1999, eight patients with this lesion (five females, three males), with a mean age of 40.5 years (range 20–54), were identified out of 1354 operated for tumours of the central nervous system. Among the eight, two were familial. They were half sisters 38 and 28 years-old, who were diagnosed to have colloid cysts of the third ventricle on CT scanning. Transcortical excision yielded 10 and 15 mm sized colloid cysts, respectively. Moreover, both sisters developed a multinodular goiter associated with these congenital tumours. The second sibling developed hyperprolactinemia associated with macroprolactinemia. Pregnancy was only possible after bromocriptine treatment. These cases provide further evidences that colloid cysts probably have an autosomic recessive pattern of inheritance with variable penetrance. 相似文献
107.
Andrea Charbonneau Ely MD MSc ; K. Allen Greiner MD MPH ; Wendi Born PhD ; Sandra Hall PhD ; Paula C. Rhode PhD ; Aimee S. James PhD MPH ; Nicole Nollen PhD ; Jasjit S. Ahluwalia MD MPH MS 《The Journal of rural health》2006,22(4):364-366
CONTEXT: Although clinical guidelines recommend routine screening and treatment for obesity in primary care, lack of agreement between physicians and patients about the need for obesity treatment in the primary care setting may be an unexplored factor contributing to the obesity epidemic. PURPOSE AND METHODS: To better understand this dynamic, we surveyed 439 obese patients (body mass index >or=30) at the time of clinic visits in 2003 at diverse primary care settings in rural Kansas and conducted same-day interviews with their physicians (N = 28). We used Spearman's correlation to describe and compare patient and physician responses. FINDINGS: Most patients were women (66%). Their mean age was 55.8 years, and mean body mass index was 37.7. Half (51%) reported discussing their weight on that visit date. Overall, 51% of patients wanted to discuss weight more often with their physician and 54% wanted to discuss weight sooner. Patients and physicians gave similar assessments of the patient's preference for discussing weight loss, how often weight was discussed at visits, and the patient's motivation for weight loss. Spearman's correlations on these variables were .33, .54, and .25, respectively (all P < .001). CONCLUSIONS: These patients and their physicians demonstrated a weak to moderate agreement on several variables crucial to initiating and continuing obesity care. Understanding patient and provider beliefs and preferences regarding obesity diagnosis and treatment is essential in designing obesity interventions for primary care. 相似文献
108.
The phenotype of severe congenital hydrocephalus secondary to neural cell adhesion molecule L1 (L1CAM) gene mutations includes the distinct finding of brainstem corticospinal tract hypoplasia. Using diffusion-weighted imaging (DWI), we failed to demonstrate anisotropy in the corticospinal tracts of the basis pontis in 4 affected boys with L1CAM mutations. The DWI findings correlated with the neuropathological findings in a fifth patient. DWI may be a useful technique to screen for boys with L1CAM mutations. 相似文献
109.
110.
目的探讨肝局灶性结节增生(FNH)不典型的螺旋CT征象。方法对病理证实或临床确诊的32例FNH患者37个病灶的螺旋CT征象进行回顾性分析。结果 37个病灶中,有 14个病灶直径≤3 cm,23个病灶直径>3 cm;7个病灶周边存在假包膜;22个病灶存在中央瘢痕, 其中有20个病灶直径>3 cm;所有病灶在动脉期均呈高密度,其中31个病灶肿瘤实质均匀强化。结论多发病灶、存在假包膜、无中央瘢痕、动脉期不均匀强化是FNH不典型的CT征象。征象的多样性与病灶的病理类型和病灶的直径相关。 相似文献