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PubMed1994

Effects of hyperactivity of the maternal hypothalamic-pituitary-adrenal (HPA) axis during pregnancy on the development of the HPA axis and brain monoamines of the offspring.

Offspring of mothers with adrenal hyperactivity during pregnancy have been reported to have changes in brain monoamines and altered emotional, reactive, sexual and maternal behavior. Since the hypothalamic-pituitary-adrenal (HPA) axis is known to be involved in the expression of such behaviors and is itself under monoaminergic control, we examined the development of the HPA axis and brain monoamines in pups whose mothers had adrenal hyperactivity, reflecting administration of ACTH during the last third of their pregnancy. The adrenals of the experimental animals weighed less and had aberrant morphology. The abnormal histology was more pronounced in the adrenals of the experimental females than of the males, suggesting that females were more vulnerable to the prenatal treatment. In both experimental males and females, basal plasma corticosterone levels were higher compared to the controls, while after exposure to stress, experimental animals attained lower plasma corticosterone levels than the controls. In the brain of the experimental animals, dopaminergic activity appeared to be decreased, while serotonergic activity increased. Our results indicate that the prenatal treatment affected brain development in the offspring and as a consequence programmed the developing HPA axis in such a way as to hyperfunction under basal conditions, leading to its exhaustion and its inability to react properly to stress.

Adrenal Glands↗

PubMed1995

The angle of the dorsoventral axis with respect to the anteroposterior axis in the Drosophila embryo is controlled by the distribution of gurken mRNA in the oocyte.

Like most organisms, Drosophila embryos develop in relation to two orthogonal axes, the anteroposterior and dorsoventral. These two axes are established by four independent systems of maternal information. Mutations in any system disrupt either the anteroposterior or the dorsoventral patterning of the embryo but never affect the orthogonal orientation of the axes relative to each other. Here we show by analyzing their embryonic fate map, that K10 embryos still possess a dorsoventral polarity. However, instead of forming a 90 degrees angle, the dorsoventral and the anteroposterior axes lie parallel to each other. This axis misorientation was partially corrected by decreasing the wild-type grk gene copy number such that the embryos issued from K10/K10; grk/+ females showed a variability in their fate map which could be interpreted as a progressive rotation of dorsoventral axis relative to the unmodified anteroposterior axis. This rotation is maximal in the K10 embryos where it reaches 90 degrees and results in the congruence of the two axes. The alteration of the embryonic fate map could be traced back to oogenesis where it was shown to correlate with the mislocalization of the grk transcripts.

Animals↗

PubMed2006

A clinical comparison of patellar tracking using the transepicondylar axis and the posterior condylar axis.

Two different methods for femoral component rotation in total knee arthroplasty (TKA) were compared with regard to the need for lateral retinacular release and 3-year follow-up knee society scores of both patellofemoral function and 3-year radiographs of the patella. The posterior condylar axis was used in 1322 consecutive primary TKAs, and the transepicondylar axis (TEA) was used in 1059 consecutive primary TKA. A significant decrease in lateral retinacular release was observed from 56.9% (752 knees) using the posterior condylar axis down to 12.3% (130 knees) using the TEA. No significant differences in knee society scores were observed between the 2 groups with regard to stair climbing, pain, patella radiographs, or range of motion. Routine use of the TEA is recommended for determining femoral component rotation in TKA.

Aged↗

PubMed2005

Activation of the hypothalamic-pituitary-adrenal axis and autonomic nervous system during inflammation and altered programming of the neuroendocrine-immune axis during fetal and neonatal development: lessons learned from the model inflammagen, lipopolysaccharide.

The hypothalamic-pituitary-adrenal axis (HPAA) and autonomic nervous system (ANS) are both activated during inflammation as an elaborate multi-directional communication pathway designed to restore homeostasis, in part, by regulating the inflammatory and subsequent immune response. During fetal and neonatal development programming of the HPAA, ANS and possibly the immune system is influenced by signals from the surrounding environment, as part of an adaptive mechanism to enhance the survival of the offspring. It is currently hypothesized that if this programming is either misguided, or the individual's environment is drastically altered such that neuroendocrine programming becomes maladaptive, it may contribute to the pathogenesis of certain diseases. Current research, suggests that exposure to inflammatory signals during critical windows of early life development may influence the programming of various genes within the neuroendocrine-immune axis. This review will provide, (1) an overview of the HPAA and ANS pathways that are activated during inflammation, highlighting studies that have used lipopolysaccharide as a model inflammagen and, (2) evidence to support the hypothesis that inflammatory stress during fetal and neonatal development can alter programming of the neuroendocrine-immune axis, influencing stress and immune responsiveness, and possibly disease resistance later in life.

Acute-Phase Reaction↗

PubMed1999

Temporal differences in the responses of the pituitary adrenocortical axis, the sympathoadrenomedullar axis, heart rate, and behaviour to a daily repeated stressor in domestic pigs.

In this study we examined responses of domestic pigs (Sus scrofa domestica) to a daily repeated stressor. In particular, we focused on differences in temporal changes across treatment repetition between the pituitary adrenocortical axis, the sympathoadrenomedullar axis, heart rate, and behaviour. To induce a stress response, we separated eight castrated male pigs from their group mates visually and auditorily for 1 h on 10 successive days. Overall, enhanced plasma levels of cortisol, ACTH, and adrenaline indicated a clear stress response. Levels of cortisol and ACTH decreased continuously with repetition of exposures to the stressor. In contrast, levels of adrenaline, behavioural activity, and heart rate did not change consistently across repetition of exposures. Interestingly, therefore, hormones of the pituitary adrenocortical axis showed a process of adaptation whereas subjects did not adapt to the stressor with respect to titres of adrenaline, heart rate, and particular behaviours (e.g., grid pressing, vocalisation, locomotion). Instead, they continued to react actively towards the social separation. Our results suggest that different stress systems can differ in temporal pattern of their response towards a repeated stressor. Such temporal differences should be considered when studying the effects of repeated stress.

Adaptation, Physiological↗

PubMed1998

Inhibition and activation of the thyroidal axis by the adrenal axis in vertebrates.

Hormones of the adrenal or interrenal axis and stress situations which induce elevated glucocorticoid plasma levels (e.g. handling and starvation), inhibit thyroid function in growing and adult vertebrates. However, data indicate that during foetal and embryonic development (mammals and birds) or during larval growth and metamorphosis (fish and amphibians), the adrenal axis may stimulate thyroid function. Recent findings have provided some information concerning this stimulatory interference of the adrenal axis. In amphibians corticotropin releasing hormone and not thyrotropin releasing hormone is thyrotropic during metamorphosis, thus providing the substrate T4 necessary for T3 production. Other data indicate that the increase in plasma T3 at metamorphic climax may be the result of an inhibition of the T3 degrading activity, rather than stimulation of the T4 into T3 converting activity, and that glucocorticoids may be responsible for this. Also, in the chick embryo glucocorticoids effectively increase plasma T3 concentration by reducing the hepatic T3 degrading activity, whereas corticotropin releasing hormone also induces an elevation in the thyrotropin plasma levels and hence raises T4 concentrations which may function as a substrate for T3 production.

Adrenal Glands↗

PubMed1999

Hypothalamo-pituitary-adrenal axis and growth hormone axis in patients with rheumatoid arthritis.

Rheumatoid arthritis (RA) is a systemic disease and is associated with cytokines (IL-1, IL-6, TNF-alpha) production. There is little information on hypothalamo-pituitary-adrenal (HPA) axis and growth hormone (GH) axis in the patients with RA. We have, therefore, investigated these systems in twenty patients with confirmed RA. Ten of the patients had active and 10 patients remitted RA. Serum cortisol, ACTH and GH levels were measured in the basal state and after insulin induced hypoglycaemia. Cortisol, adrenocorticotropic hormone (ACTH) and GH responses were impaired in 65%, 85% and 30% of the patients, respectively. The basal and peak hormone levels were similar between the patients with active RA and the patients in remission. These findings indicate that there is an impairment in HPA and GH axis in patients with active and remitted RA. The site of this impairment is probably hypothalamus and/or pituitary gland.

Adolescent↗

PubMed2003

Stability as a distinction between Axis I and Axis II disorders.

Temporal stability has served as a conceptual basis for the distinction between the clinical syndromes of Axis I disorders and the Axis II personality disorders, the latter being viewed as lifelong enduring patterns. However, comparisons of the stability of Axis I and II disorders have been limited. The present review examines findings from three naturalistic longitudinal studies that utilize similar methodology: the Collaborative Longitudinal Personality Disorders Study (CLPS; Gunderson et al., 2000), the Collaborative Depression Study (CDS; Katz & Klerman, 1979), and the Harvard/Brown Anxiety Research Program (HARP; Keller et al., 1994). Using a definition of remission/recovery as having no or minimal symptoms for 8 consecutive weeks, the courses of personality, depressive, and anxiety disorders were compared. Though remission/recovery rate at the 2-year follow-up was highest for mood disorders, the probability of recurrence was also particularly high. Personality disorders, with remission rates higher than the anxiety disorders, appear to be less stable than conceptualized. The anxiety disorders had remarkably low recovery rates even beyond 5 years of prospective follow-up. Factors that may explain these findings, as well as implications for future conceptualization of DSM, are discussed.

Anxiety Disorders↗

PubMed1988

The diagnostic dilemma of myxedema and madness, axis I and axis II: a longitudinal case report.

A patient with presumed chronic paranoid schizophrenia had chronic thyroiditis and Grade I hypothyroidism. Psychosis cleared following treatment with thyroid replacement. The probable presence of two axis II disorders may have contributed to the missed medical diagnosis and the patient's eventual suicide. The personality disorders were a major problem in the patient's medical and psychiatric care. The differential diagnosis among hypothyroidism and primary axis I psychotic and depressive psychopathology has always been problematic. When axis II pathology is also present, the diagnostic dilemma is increased.

Adult↗

PubMed1987

Injuries of the atlas and axis. A follow-up study of 85 axis and 10 atlas fractures.

In a follow-up study of ten atlas and 85 axis fractures, 12% had residual symptoms in the form of local and radiating cervical pain. The residual symptoms were interpreted as a sign of a mild demyelinating process initiated by the trauma of the medulla. At least 22% of the accidents occurred while the person was under the influence of drugs or alcohol. Therefore, a wide range of residual symptoms (progressive or nonprogressive) could be attributed in part to abuse of drugs and alcohol. A permanent measurable loss of motion occurred following injury to the atlas or axis, irrespective of the modality of treatment. Cervical fusion created the greatest loss of motion and collar immobilization the least. Skull traction and a halo-vest were intermediate in patients with loss of motion, and the degree of loss of range was essentially equal. Residual symptoms, including pain, were found in 20% of those treated with a collar, 40% of those treated with surgical methods, 5% of those treated with traction, and 5% of those treated with a Halo-vest. Residual symptoms did not correlate at all with degree of displacement of the original fracture.

Adult↗

PubMed1995

Corticosterone, brain mineralocorticoid receptors (MRs) and the activity of the hypothalamic-pituitary-adrenal (HPA) axis: the Lewis rat as an example of increased central MR capacity and a hyporesponsive HPA axis.

In this study we report a series of differences in brain and peripheral elements regulating the hypothalamic-pituitary-adrenal (HPA) axis between male LEW and Wistar rats. We found: (i) differential properties of mineralocorticoid receptors (MRs) and glucocorticoid receptors (GRs) in the brain (hippocampus, hypothalamus) and pituitary: LEW rats displayed an increased capacity of MRs in the hippocampus and hypothalamus and a decreased capacity of glucocorticoid receptors GRs in the pituitary. The binding affinity (Kd) for MRs and GRs in the hippocampus was comparable. (ii) Lower concentrations of corticotropin releasing hormone (CRH) mRNA were detected in the nucleus paraventricularis of the hypothalamus of LEW rats. (iii) Adrenal weight was similar in LEW and Wistar rats; however, LEW rats had about 30% less adrenocortical cells. Subjecting adrenocortical cells to increasing doses of ACTH1-24 in vitro resulted in about a 60% smaller release of corticosterone in LEW rats. (iv) LEW rats escaped dexamethasone suppression showing increased basal levels of endogenous ACTH, but responded with a comparable release of corticosterone to the IV injection of 5 ng ACTH1-24. (v) LEW rats responded to a variety of stimuli: adrenalectomy under ether anaesthesia, a novel environment, a tail nick and restraint or an immunological challenge, with lower circulating ACTH and corticosterone plasma levels than Wistar rats. (vi) Evening levels of ACTH and corticosterone were lower in LEW than Wistar rats but did not differ in the morning. Blockade of brain MRs in the evening by a central injection of the specific MR antagonist RU28318 in LEW rats resulted in increased circulating levels of ACTH and corticosterone. (vii) Levels of corticosteroid-binding proteins were lower in one-day adrenalectomized LEW rats, indicating higher levels of free corticosterone. (viii) LEW rats had a smaller thymus than Wistar rats. Taken together, the receptor binding data correspond to a decreased neuroendocrine responsiveness of LEW rats to stress. We suggest that the shift in the central MR/GR balance of LEW rats, i.e. augmented MR-mediated effects of corticosterone, is the central regulating mechanism of the hyporeactive HPA axis in this rat strain. Lower levels of CRH mRNA in the hypothalamus and lower levels of ACTH and corticosterone in response to various stimuli, as well as the hyporesponsive adrenals to exogenous ACTH, are apparently the consequences of the life-long suppressive action of corticosterone via central MRs.

Adrenocorticotropic Hormone↗

PubMedDate not supplied

Fusion of short-axis and long-axis cardiac MR images.

A method for fusion of the short-axis and long-axis cardiac MR images into an isotropic volume image is introduced. A volume image obtained by this method contains the left ventricular (LV) cavity in one piece, facilitating measurement of its shape and volume. The main goal in this image fusion is to reconstruct the LV cavity in volume form and in high resolution. The accuracy of the method is measured using a synthetic image, and examples of image fusion using real images are presented.

Diastole↗

PubMed2000

The effects of a continuous infusion of hexarelin on pulsatile growth hormone release, growth axis and galanin gene expression and on the response of the growth axis to growth hormone-releasing hormone.

The effect of a 6 hour continuous infusion of Hexarelin (100 micrograms/hour) on GH peak frequency, amplitude and duration, GH trough concentrations, the interval between successive peaks and the pituitary responsiveness to GHRH, as well as GH axis and galanin mRNA contents, were examined in conscious adult male rats. Plasma GH concentrations peaked within 15 minutes after the initiation of Hexarelin infusion, but returned to baseline levels by 60 minutes. No significant differences between Hexarelin and saline infused rats were noted for any of the parameters of pulsatile GH release analyzed. However, following a 6 hour infusion, rats treated with Hexarelin demonstrated a greater GH responsiveness to GHRH (delta GH: 57 +/- 16 ng/ml for Hexarelin infused; 21 +/- 7 ng/ml for saline infused; p < 0.05). Furthermore, the rats infused with Hexarelin demonstrated decreased GHRH and increased hypothalamic galanin mRNA contents as compared to the saline infused rats, while hypothalamic somatostatin and pituitary GH mRNA contents appeared unchanged. Rats infused with Hexarelin had lower pituitary galanin mRNA content than did the rats which were infused with saline. Collectively, these results suggest that Hexarelin may not act via alteration of somatostatin synthesis and that suppression of somatostatin's action at the pituitary can not be excluded. The current study also suggests that other hypothalamic pathways aside from those currently defined for the growth axis may be involved in the mechanism by which Hexarelin and the other GH-releasing peptides elicit GH release.

Animals↗

PubMed2003

Axis I and axis II disorders as predictors of prospective suicide attempts: findings from the collaborative longitudinal personality disorders study.

This study examined diagnostic predictors of prospectively observed suicide attempts in a personality disorder (PD) sample. During 2 years of follow-up, 58 participants (9%) reported at least 1 definitive suicide attempt. Predictors that were examined include 4 PD diagnoses and selected Axis I diagnoses (baseline and course). Multivariate logistic regression analyses indicated that baseline borderline personality disorder (BPD) and drug use disorders significantly predicted prospective suicide attempts. Controlling for baseline BPD diagnosis, proportional hazards analyses showed that worsening in the course of major depressive disorder (MDD) and of substance use disorders in the month preceding the attempt were also significant predictors. Therefore, among individuals diagnosed with PDs. exacerbation of Axis I conditions, particularly MDD and substance use, heightens risk for a suicide attempt.

Adult↗

PubMedDate not supplied

Comparing Personality Diagnostic questionnaire-4+ with Longitudinal, Expert, All Data (LEAD) standard diagnoses in a sample with a high prevalence of axis I and axis II disorders.

A comparison between the Personality Diagnostic Questionnaire-4+ (PDQ-4+) and Longitudinal, Expert, All Data (LEAD) standard diagnoses was made in a sample of 100 patients with a high prevalence of both axis I and axis II disorders. The internal consistency was considered acceptable (alpha >.70) for 3 of 12 PDQ-4+ scales. Diagnostic agreement between the assessment methods was poor for specific personality disorders (PDs). The PDQ-4+ gave many false-positive diagnoses. Changing the diagnostic thresholds only marginally increased the agreement between methods or the diagnostic efficiency of the PDQ-4+. Multiple regression analyses showed that the discrepancies between the methods were strongly associated with the current level of perceived symptoms (SCL-90-R).

Adult↗

PubMed1975

[Estimation of ventricular volume derived from three transverse diameters and the longitudinal axis, compared with an area-longitudinal axis method (author's transl)].

The difficulty of automatic volume estimations of the left ventricle from cine-ventriculography lies in the accurate definition of the ventricular contour during the whole of the cardiac cycle. On the other hand, automatic determination of the long axis of the ventricle, and of three transverse diameters, is feasible. An attempt was therefore made to see whether accurate ventricular volume estimations could be obtained from these measurements. Two different geometrical models were examined: a) A complete rotational ellipsoid b) A half rotational ellipsoid. Examination of ten cine-ventriculograms (totalling 546 frames) has shown that the ventricular volume can be determined with an adequate accuracy by this method. The half ellipsoid model produced better mean results than the full ellipsoid. Its mean deviation from the area-long axis method was only minus 1.2%, that of the complete ellipsoid was minus 3.3%.

Heart Function Tests↗

PubMed1999

Reproductive cycles of farmed female chital deer (Axis axis).

Studies were conducted on chital deer hinds (Axis axis) living in a temperate region to advance the understanding of the patterns of reproduction of a tropical cervid species. The hinds exhibited regular patterns of oestrus cyclicity throughout the year as evidenced by concentrations of serum progesterone monitored over a 14-month period, and detection of behavioural oestrus by vasectomized stags. The mean length of the oestrous cycle was 18.0+/-0.7 days (range, 12-23 days). Profiles of serum progesterone showed concentrations of <0.5 ng mL(-1) at the time of oestrus, which rose to a peak (range 1.5-5.0 ng mL(-1)) about Day 13, and then declined to low concentrations at the next oestrus. Observations following parturition showed that the first detected oestrus occurred at a mean (+/- SEM) time of 26.9+/-3.0 days later for seven of nine hinds. The mean length of the oestrous cycle after the first post-partum oestrus was 16.6+/-1.0 days (range 7-20 days). The presence of a stag may influence the length of the post-partum period in chital deer hinds, and hinds in contact with a stag in this study had a significantly shorter interval from parturition to first ovulation (P<0.01) compared with hinds not in contact with a stag. By 7 weeks post partum a corpus luteum was detected in 93% of hinds. In comparison only 43% of hinds with no stag contact had a corpus luteum by 7 weeks post partum. It is suggested that the tendency towards seasonal calving in the study population may be related more to male than female factors.

Animals↗

PubMed2003

Intrinsic aspect of V-shaped switching in ferroelectric liquid crystals: biaxial anchoring arising from peculiar short axis biasing in the molecular rotation around the long axis.

To clarify the intrinsic aspect of practically usable thresholdless V-shaped switching in ferroelectric liquid crystals, we have observed textures and measured polarized Raman scattering as well as optical transmittance in a thin homogeneous cell of a single compound by applying an electric field. The results indicate that the so-called surface stabilized ferroelectric states are destabilized, and that there exist rather stable two domains with broad and narrow molecular orientational distributions, both of which show the almost ideal V-shaped switching with considerably low transmittance at the tip of the V. We have concluded that the main cause of the V-shaped switching is the biaxial anchoring on the substrates coated with polyimide, which makes the most polarizable short axis normal to the substrates. It is in competition with the ordinary anchoring that favors the director parallel to the substrates, when the material has such a bulk intrinsic property that this short axis is parallel to the tilt plane. The competition makes the total anchoring energy almost independent of the azimuthal angle and gives rise to the V-shaped switching.

Journal Article↗