Search PubMed⌕ Search

Biomedical subjects

M Maes

Publications and source records attributed to M Maes.

At least 217 records · Page 12Linked to original sources
PubMed1994

Natural killer cell activity in major depression: relation to circulating natural killer cells, cellular indices of the immune response, and depressive phenomenology.

1. Recently, blunted natural killer cell activity (NKCA) has been found in major depression. The present study investigates the relationships between ex vivo blunted NKCA in major depression, number or percentage of NKC, in vivo indices of systemic immune activation and depressive phenomenology. 2. Toward this end, NKCA, absolute number of leukocytes and number or percentage of lymphocytes, monocytes, neutrophils, activated T lymphocytes (HLA-DR+, CD25+) and NKC (CD3-CD56+) were determined in 13 normal controls and 36 depressed inpatients. 3. NKCA was significantly and positively related to number and percentage of NKC in the peripheral blood. The major depression-related reduction in NKCA was not related to alterations in peripheral NKC. There were significant negative correlations between NKCA and number or percentage of leukocytes, monocytes, neutrophils and HLA-DR+ T cells. Up to 50% of the variance in NKCA could be explained by the regression on the number of monocytes, percentage of HLA-DR+ T and NKC cells, and diagnostic classification. Up to 43% of the variance in NKCA was explained by depressed mood, somatic anxiety and less diurnal variation. 4. The results show that blunted NKCA in major depression is not related to alterations in peripheral NKC, but reflects in part the systemic immune activation in that illness.

Adult↗
PubMed1994

Adrenocorticotropic hormone, beta-endorphin and cortisol responses to oCRH in unipolar depressed patients pretreated with dexamethasone.

1. Corticotropin-releasing hormone (ovine CRH, 100 micrograms intravenous bolus) was given to 63 unipolar depressed inpatients following the 1 mg overnight dexamethasone suppression test (DST). The depressed patients included 18 minor, 24 simple major and 21 melancholic subtypes. 2. Baseline or postdexamethasone plasma levels of intact adrenocorticotropic hormone (ACTH), beta-endorphin/beta-lipotropin (beta END/beta LPH), cortisol, and dexamethasone were measured, as well as the post DST+CRH hormone responses. 3. CRH administration 9.5 hr after dexamethasone resulted in a significant enhancement of ACTH, beta END/beta LPH and cortisol secretion. The post DST+CRH ACTH and beta END/beta LPH- but not cortisol-values exceeded their baseline hormone levels. The post DST+CRH ACTH--but not beta END/beta LPH or cortisol-levels were significantly higher in major depressives compared to minor depressives. The post DST+CRH ACTH and beta END/beta LPH--but not cortisol-levels were significantly higher in DST nonsuppressors than suppressors. The post DST+CRH ACTH levels were significantly and positively related to severity of illness. 4. The results provide evidence that the pathophysiology underlying the abnormal DST+CRH and DST tests in melancholia is localized at the pituitary level and may consist of a CRH-driven breakthrough of corticotropic cell secretion synergized by central and peripheral agents, in conjunction with a decrease in glucocorticoid feedback suppressibility.

Adrenocorticotropic Hormone↗
PubMed1994

Effects of age on spontaneous cortisolaemia of normal volunteers and depressed patients.

The aim of this study was to characterize the relationships between age and endogenous cortisol secretion in healthy controls and in major depressed patients between 18 and 58 years of age. Toward this end, the authors measured morning basal plasma cortisol secretion every 30 min from 0900 h until 1100 h and computed the integrated morning cortisol secretion in 80 normal controls and 118 major depressed patients. A significant negative correlation between age and plasma morning cortisol was found in normal volunteers but not in major depressives. The observed decrease in cortisol secretion with age in normal controls older than 35 years does not occur in major depressives. The middle age (+/- 35 years) appears to be an important turning point in hypothalamo-pituitary-adrenal (HPA)-axis function of normal persons vs. major depressives.

Adolescent↗
PubMed1994

Multiple reciprocal relationships between in vivo cellular immunity and hypothalamic-pituitary-adrenal axis in depression.

Major depression is reportedly characterized by increased activity of the hypothalamic-pituitary-adrenal (HPA) axis and by in vivo immune activation. The present study was carried out in order to investigate the relationships between HPA-axis activity and in vivo immune function in depression. Towards this end the following parameters were measured: 24 h urinary cortisol (UC) excretion; basal and post-dexamethasone (DST) plasma cortisol, beta-endorphin/beta-lipotropin (beta END/beta LPH) and dexamethasone concentrations; and leucocyte subsets (i.e. lymphocytes, neutrophils, monocytes, CD4+, CD4+CD45RA+, CD4+CD45RO+, CD8+, CD8+CD57+, CD8+CD57-, HLA-DR+, CD25+ T cells, HLA-DR+, CD19+, CD20+, and CD21+ B cells) both pre- and post-DST. Dexamethasone administration (1 mg orally) induced leucocytosis, lymphocytopaenia, monocytopaenia and neutrophilia. HPA-axis non-suppressors exhibited a relative resistance to the enhancing (e.g. neutrophils) or depressant (e.g. lymphocytes, CD4+ T cells) effects of dexamethasone. There were significant correlations between UC excretion and the number of percentage of lymphocytes, monocytes, CD4+CD45RA+ and CD8+CD57- T cells (negatively) and neutrophils (positively). It is concluded that multiple and complex intertwined relationships between HPA-axis hyperactivity and systemic immune stimulation participate in the pathophysiology or pathogenesis of major depression.

Adult↗
PubMed1994

Immune-inflammatory markers in schizophrenia: comparison to normal controls and effects of clozapine.

The purpose of this study was to investigate immune-inflammatory markers in schizophrenia and the effects of chronic treatment with clozapine, an atypical antipsychotic agent, on these variables. Toward this end, we measured interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R) and sIL-2R in the blood of 26 normal controls and 14 schizophrenic patients before and after treatment with clozapine. The sIL-2R and IL-6 levels were significantly higher in younger (< 35 years) schizophrenic subjects than in normal controls and older (> or = 35 years) schizophrenic subjects. The sIL-6R levels were significantly lower in schizophrenic subjects than in normal controls. Chronic treatment with clozapine significantly increased the blood concentration of sIL-2R; the increases in the latter were significantly related to the dose of clozapine but not to changes in severity of positive or negative symptoms. We conclude that: (a) schizophrenia in younger people is accompanied by increased IL-6 and sIL-2R secretion; and (b) subchronic treatment with clozapine increases sIL-2R levels. Increased plasma sIL-2R may be one mechanism by which neuroleptics exhibit their immunosuppressive effects.

Adult↗
PubMed1994

Lower degree of esterification of serum cholesterol in depression: relevance for depression and suicide research.

Previous studies have suggested that depression and suicide are related to alterations in total cholesterol serum concentrations, and that an altered distribution of haptoglobin (Hp) phenotypes in major depression indicates that variation on chromosome 16 may be associated with that illness. Lecithin:cholesterol acyl transferase (LCAT, EC 2.3.1.43), the enzyme that catalyzes the esterifying reaction of cholesterol in serum, is located close to the Hp gene. This study examined the serum concentrations of total and free cholesterol and the esterified cholesterol ratio in 26 healthy controls, 47 unipolar depressed subjects (16 minor, 14 simple major and 17 melancholic depressed subjects) and 12 relatives of melancholic subjects. Depressed subjects (regardless of subtype) and relatives of depressed subjects had a significantly lower esterified cholesterol ratio than normal controls. No significant differences in total or free cholesterol concentrations were found between the above study groups. In depressed subjects, there were no significant relationships between the esterified cholesterol ratio, total or free cholesterol and postdexamethasone adrenocorticotropic or cortisol values, Hp phenotypes, severity of illness or suicidal symptoms. It is hypothesized that lower esterification in serum cholesterol may constitute a vulnerability factor for depression through alterations in cell membrane microviscosity.

Adult↗
PubMed1994

Synchronized annual rhythms in violent suicide rate, ambient temperature and the light-dark span.

To investigate whether violent and nonviolent suicide and homicide are related to atmospheric or geomagnetic activity, we investigated the relationships between weekly number of suicides or homicides for all Belgium for the period 1979-1987, and ambient temperature, relative humidity, air pressure, hours of sunlight and precipitation per day, wind speed and geomagnetic index. The occurrence of violent suicide was significantly and positively related to ambient temperature, sunlight duration, an increase in temperature over the few past weeks, and negatively to relative humidity. Higher ambient temperature and an increase in air temperature over the few past weeks were the most significant climatic predictors of violent suicide rate. A highly significant common annual rhythm with a common acrophase of 190 degrees was detected in violent suicide rate, ambient temperature and sunlight duration. No significant time-relationships between nonviolent suicide or homicide and any of the weather variables were found. It is concluded that i) violent suicide may be related to short-term fluctuations in the weather and in particular to temperature; and ii) the annual rhythm in violent suicide may be synchronized by the annual rhythms in ambient temperature and light-dark span.

Belgium↗
PubMed1994

Absolute number and percentage of circulating natural killer, non-MHC-restricted T cytotoxic, and phagocytic cells in unipolar depression.

One of the most consistently reported immunological abnormalities in major depression is blunted ex vivo natural killer cell activity (NKCA). This study was designed to investigate the number and percentage of circulating natural killer cells (NKC) in a group of patients with unipolar depression. In addition, the number and percentage of other phagocytic/cytotoxic cells were determined. The following cell subsets were investigated: number of leukocytes, monocytes, neutrophils, lymphocytes, NKC (CD16+ or CD56+), and non-MHC-restricted cytotoxic T lymphocytes (CTL) in 17 healthy controls and 79 depressed subjects. There were no differences either in absolute number or percentage of NKC, or CTL between healthy controls, minor, simple major, and melancholic depressed subjects. Depression per se was characterized by a leukocytosis due to monocytosis and neutrophilia. Our results do not support the thesis that depression-related blunted NKCA is caused by a decreased number or percentage of NKC in peripheral blood.

Adjustment Disorders↗
PubMed1994

Ultrasensitive assay for measuring the intact (1-39) ACTH molecule: an asset in depression research.

This study investigates the utility for depression research of an assay for intact (1-39) adrenocorticotropic hormone (ACTH) versus that of a previously employed (i.e., 1-17, 1-24 sequences) ACTH assay. ACTH plasma levels were measured using two different ACTH assays (labeled as intact versus nonintact) in 10 minor and 27 major depressed subjects undergoing the combined dexamethasone suppression (DST) and corticotropin-releasing hormone (CRH) test. Intact--but not nonintact--ACTH values were significantly correlated with the severity of illness. Major depressed subjects exhibited significantly higher post-DST+CRH intact ACTH values than minor depressives, whereas nonintact ACTH values were not significantly different between these groups. Post-DST+CRH intact ACTH values were significantly more closely related to post-DST+CRH cortisol than nonintact ACTH values. It is concluded that the assay of the intact ACTH molecule is an asset in depression research and should replace the previous less specific and sensitive ACTH assays.

Adrenocorticotropic Hormone↗
PubMed1994

Psychoimmune investigation in obsessive-compulsive disorder: assays of plasma transferrin, IL-2 and IL-6 receptor, and IL-1 beta and IL-6 concentrations.

This study was carried out to investigate the immune function in obsessive-compulsive disorder (OCD). Plasma levels of interleukin (IL)-1 beta, IL-6, soluble IL-6 receptor (sIL-6R), sIL-2R, and transferrin receptor (TfR), and baseline plasma cortisol levels were measured in 19 OCD patients and 19 normal controls. No significant differences in any of the above immune variables were found between subjects with OCD and normal controls. There was a significant positive correlation between IL-6 or sIL-6R concentrations and severity of compulsive--but not obsessive--symptoms. In subjects with OCD, there was a significant negative relationship between sIL-2R concentrations and plasma cortisol values. In subjects with OCD and in the study group as a whole, there were significant positive relationships between sIL-2R and TfR concentrations.

Adult↗
PubMed1994

Evidence for the existence of major depression with and without anxiety features.

Several studies have reported on comorbidity between depression and anxiety. The present study investigates the occurrence of anxiety symptoms during an episode of unipolar depression. The authors administered the 15-item Rating Scale for Anxiety States of Hamilton (HAM-A) to 73 depressed inpatients categorized according to DSM-III criteria into minor (300.40, 309.00), major depression without (296.X2) and with (296.X3) melancholia. Principal-component (PC) analysis revealed three interpretable PCs: a somatic anxiety, a depression-anxiety overlap, and an anxious mood-behavior factor. Subjects with major depression showed significantly higher ratings on total HAM-A score, the three above PCs, and on all HAM-A items (except general somatic muscular and genitourinary symptoms) than subjects with minor depression. A cluster analysis generated two stable, qualitatively distinct clusters: i.e. one with severe anxiety and one with no or minimal anxiety; the six most discriminating symptoms were: tension, behavior at interview (general or physiological), respiratory, genitourinary and autonomic symptoms. Up to 95.4% of patients allocated to the severe anxiety cluster were major depressives. The results suggest that major depression may be divided into two qualitatively distinct classes, i.e. major depression with and without anxiety features.

Adjustment Disorders↗
PubMed1994

Haptoglobin phenotypes and gene frequencies in unipolar major depression.

OBJECTIVE: Studies from the authors' laboratory have shown that major depression is accompanied by significantly increased plasma concentrations of positive acute-phase proteins such as haptoglobin. Haptoglobin is characterized by a molecular variation with three known phenotypes (Hp 1-1, Hp 2-1, and Hp 2-2). This study investigated haptoglobin plasma levels and phenotype and gene frequencies in unipolar major depression. METHOD: Haptoglobin plasma levels of 22 healthy volunteers, 32 patients with minor depression, and 72 patients with major depression were determined by means of a laser nephelometric method. Haptoglobin phenotyping of these 126 subjects and 200 healthy blood donors was also carried out. RESULTS: The patients with major depression exhibited significantly higher haptoglobin plasma levels than the healthy comparison subjects and the patients with minor depression. Subjects with the haptoglobin phenotype Hp 2-2 had significantly lower haptoglobin levels than the phenotype Hp 1-1 and Hp 2-1 carriers. The frequencies of haptoglobin phenotypes Hp 2-1 (61.1%) and Hp 2-2 (20.8%) in the patients with major depression were significantly higher and lower, respectively, than the frequencies in the normal population (i.e., the blood donors: 48.0% and 37.0%, respectively). The frequency of the Hp-1 gene was significantly greater in the patients with major depression (48.6%) than in the normal population (39.0%). CONCLUSIONS: Major depression is characterized by a hyperhaptoglobinemia that is largely independent of haptoglobin phenotypes. This altered distribution of haptoglobin phenotypes and genes suggests that genetic variation on chromosome 16 may be associated with that illness.

Adult↗
PubMed1994

Growth hormone therapy in Turner's syndrome: one versus two daily injections.

In 44 girls with Turner's syndrome, aged 4.0-15.3 yr, the effects of biosynthetic GH (25 U/m2.week) given as once daily or twice daily injections were compared. During 1 yr of treatment, the growth rate increased similarly by 3.5 +/- 1.3 cm/yr in the once daily group and 2.7 +/- 1.8 cm/yr in the twice daily group. Although pretreatment height velocity was negatively related to age, the increase in height velocity during therapy was not. The mean progression in bone age (TW2-RUS method), during therapy was 1.3 yr in both groups. No significant change in the median insulin secretory response to an oral glucose tolerance test was found. Serum cholesterol and triglyceride concentrations did not change significantly throughout the study in either treatment group. Thyroid hormone concentrations remained within normal limits. Normal increments in left ventricular wall thickness and left ventricular mass for age and body surface were observed after 1 yr of GH treatment. We conclude that division of the daily GH dose given to Turner's syndrome patients into two injections does not result in either a significantly different growth response or different side-effects from once daily treatment during the first year of therapy.

Adolescent↗
PubMed1994

Components of biological variation in prolyl endopeptidase and dipeptidyl-peptidase IV activity in plasma of healthy subjects.

We investigated the components of biological variation in plasma prolyl endopeptidase (PEP; EC 3.4.21.26) and dipeptidyl-peptidase IV (DPP IV; EC 3.4..14.5) activity in healthy individuals. We took monthly blood samples from 26 healthy volunteers for determination of plasma PEP and DPP IV activity during one calendar year. The estimated CVs for PEP activity were: total (CVt) = 25.0%, interindividual (CVg) = 13.9%, and intraindividual (CVi) = 16.8%. There was a statistically significant (P < 0.0001) seasonal pattern in plasma PEP activity, with significantly higher values in the fall than in the other seasons. The peak-trough difference in the yearly variation in PEP activity, expressed as a percentage of the mean, was as high as 56.8%. The estimated CVs for DPP IV activity were: CVt = 17.1%, CVg = 14.5%, and CVi = 8.2%. DPP IV activity was significantly (P < 0.0001) higher in summer than in the other seasons but the amplitude of the yearly variation was small.

Adolescent↗
PubMed1993

Relationships between increased haptoglobin plasma levels and activation of cell-mediated immunity in depression.

Recently, it was found that major depression is accompanied by an acute phase (AP) response with increased haptoglobin (Hp) plasma levels and various indices of systemic immune stimulation. The present study has been carried out in order to determine the relationships between hyperhaptoglobinemia and indices of systemic immune activation in severe depression. Toward this end, the authors investigated the relationships between Hp levels and number of leukocytes, monocytes, neutrophils, lymphocytes, and activated T lymphocytes (CD25+, HLA-DR+), in depression. Hp plasma levels were significantly higher in major depressed subjects as compared to healthy controls and minor depressives. There was a significant positive correlation between Hp levels and severity of illness. Hp plasma levels showed significant and positive relationships with the absolute number of leukocytes, neutrophils, monocytes, CD25+ and HLA-DR+ T cells. Up to 35% of the variance in Hp levels could be explained by the regression on the number of neutrophils and HLA-DR+ T cells. The results show that hyperhaptoglobinemia in major depression is significantly related to activation of cell-mediated immunity.

Adjustment Disorders↗
PubMed1993

The periodicities in and biometeorological relationships with bed occupancy of an acute psychiatric ward in Antwerp, Belgium.

Recently, some investigators have established a seasonal pattern in normal human psychology, physiology and behaviour, and in the incidence of psychiatric psychopathology. In an attempt to elucidate the chronopsy and meteotropism in the latter, we have examined the chronograms of, and the biometeorological relationships to bed occupancy of the psychiatric ward of the Antwerp University Hospital during three consecutive calendar years (1987-1989). Weather data for the vicinity were provided by a local meteorological station and comprise mean atmospheric pressure, air temperature, relative humidity, wind speed and minutes of sunlight and precipitation/day. The number of psychiatric beds occupied during the study period exhibited a significant seasonal variation. Peaks in bed occupancy were observed in March and November, with lows in August. An important part of the variability in the number of beds occupied could be explained by the composite effects of weather variables of the preceding weeks. Our results suggest that short-term fluctuations in atmospheric activity may dictate some of the periodicities in psychiatric psychopathology.

Bed Occupancy↗