28 results on '"Jabaaij, L."'
Search Results
2. Social networks and receiving informal care
- Author
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de Boer, A.H., Klerk, M., Cardol, M., Westert, G.P., Jabaaij, L., Schellevis, F.G., and Tranzo, Scientific center for care and wellbeing
- Published
- 2006
3. General practice in the Netherlands: Major findings from the second Dutch National Survey of General Practice
- Author
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Westert, G.P., Schellevis, F.G., van der Zee, J., Jabaaij, L., Schellevis, F., and Tranzo, Scientific center for care and wellbeing
- Published
- 2006
4. A comparison of disease prevalence in general practice in the Netherlands and in England and Wales
- Author
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Fleming, D., Schellevis, F.G., van der Linden, M., Westert, G.P., Jabaaij, L., and Tranzo, Scientific center for care and wellbeing
- Published
- 2006
5. A matter of disparities: Risk groups for unhealthy lifestyle and poor health
- Author
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Droomers, M., van Lindert, H., Westert, G.P., Jabaaij, L., Schellevis, F.G., and Tranzo, Scientific center for care and wellbeing
- Published
- 2006
6. The activities of general practitioners: Are they still gatekeepers?
- Author
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Cardol, M., de Bakker, D.H., Westert, G.P., Jabaaij, L., Schellevis, F.G., and Tranzo, Scientific center for care and wellbeing
- Published
- 2006
7. The design of the second Dutch National Survey of General Practice
- Author
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Schellevis, F.G., Westert, G.P., Jabaaij, L., Schellevis, F., and Tranzo, Scientific center for care and wellbeing
- Published
- 2006
8. Perceived health and consultation of GPs among ethnic minorities compared to the general population in the Netherlands
- Author
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Deville, W., Uiters, E., Westert, G.P., Groenewegen, P., Jabaaij, L., Schellevis, F.G., and Tranzo, Scientific center for care and wellbeing
- Published
- 2006
9. Morbidity, performance and quality in primary care. Dutch general practice on stage
- Author
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Westert, G.P., Jabaaij, L., Schellevis, F.G., and Tranzo, Scientific center for care and wellbeing
- Published
- 2006
10. Medical practice variation: Does it cluster within general practitioners' practices?
- Author
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de Jong, J., Groenewegen, P., Westert, G.P., Jabaaij, L., Schellevis, F.G., and Tranzo, Scientific center for care and wellbeing
- Published
- 2006
11. The immunological and psychological effects of bereavement: Does grief counseling really make a difference? A pilot study
- Author
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Beem, E.E., Hooijkaas, H., Cleiren, M.H.P.D., Schut, H.A.W., Garssen, B., Croon, M.A., Jabaaij, L., Goodkin, K., de Vries, M.J.H.J., and Department of Methodology and Statistics
- Published
- 1999
12. Self-reported stressors, symptoms complaints, and psychobiological functioning I: Cardiovascular stress reactivity
- Author
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Vingerhoets, A.J.J.M., Ratliff-Crain, J., Jabaaij, L., Tilders, F., Moleman, P., and Menges, L.J.
- Subjects
ComputingMilieux_LEGALASPECTSOFCOMPUTING - Published
- 1996
13. Sef-reported stressors, symptoms complaints, and psychobiological functioning 2: Psychoneuroendocrine variables
- Author
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Vingerhoets, A.J.J.M., Ratliff-Crain, J., Jabaaij, L., Tilders, F., Moleman, P., and Menges, L.J.
- Subjects
ComputingMilieux_LEGALASPECTSOFCOMPUTING - Published
- 1996
14. Recently enlisted patients in general practice use more health care resources.
- Author
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Jabaaij L, de Bakker DH, Schers HJ, Bindels PJE, Dekker JH, and Schellevis FG
- Abstract
BACKGROUND: The continuity of care is one of the cornerstones of general practice. General practitioners find personal relationships with their patients important as they enable them to provide a higher quality of care. A long-lasting relationship with patients is assumed to be a prior condition for attaining this high quality. We studied the differences in use of care between recently enlisted patients and those patients who have been enlisted for a longer period. METHODS: 104 general practices in the Netherlands participated the study. We performed a retrospective cohort study in which patients who have been enlisted for less than 1 year (n = 10,102) were matched for age, sex and health insurance with patients who have been enlisted for longer in the same general practice. The two cohorts were compared with regard to the number of contacts with the general practice, diagnoses, rate of prescribing, and the referral rate in a year. These variables were chosen as indicators of differences in the use of care. RESULTS: In the year following their enlistment, a higher percentage of recently enlisted patients had at least one contact with the practice, received a prescription or was referred. They also had a higher probability of receiving a prescription for an antibiotic. Furthermore, they had a higher mean number of contacts and referrals, but not a higher mean number of prescriptions. CONCLUSION: Recently enlisted patients used more health care resources in the first year after their enlistment compared to patients enlisted longer. This could not be explained by differences in health. [ABSTRACT FROM AUTHOR]
- Published
- 2007
15. THE INFLUENCE OF PSYCHOLOGICAL STRESS ON IMMUNOREGULATION OF LATENT EPSTEIN-BARR VIRUS.
- Author
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Benschop, R.J., Jabaaij, L., Oostveen, F. G., Vingerhoets, A. J. J. M., and Ballieux, R. E.
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PSYCHOLOGICAL stress ,EMOTIONS ,PSYCHOLOGY ,QUESTIONNAIRES ,IMMUNOGLOBULINS ,LYMPHOCYTES - Abstract
Two studies are presented on the influence of psychological factors on immunoregulation of latent Epstein-Barr virus (EBV) infection. In the first study, 121 students completed questionnaires on daily hassles, psychoneurotic symptoms, coping styles and loneliness. No significant association between these psychological measures and levels of antibodies to EBV was found. It was reasoned that this might be explained by the fact that the psychological stress levels were generally low. Therefore, in a second study, from a larger population of 390 students, 95 subjects were selected based on low or high scores on a daily hassles and a psychoneurotic symptom checklist. No significant relationship was found between psychological variables and EBV antibody titres or specific cytotoxic activity against autologous EBV-transformed B cells. It is concluded that in the cross-sectional studies presented, the psychological factors measured are not related to immune control of latent EBV. [ABSTRACT FROM AUTHOR]
- Published
- 1998
- Full Text
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16. DAILY HASSLES AND SYMPTOMS: THEIR RELATIONSHIP TO ENUMERATIVE IMMUNOLOGIC MEASURES.
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Jabaaij, L., Benschop, R. J., Vingerhoets, J. J. M., Kirschbaum-Buske, A., Duivenvoorden, H. J., Oostveen, F. G., and Ballieux, R. E.
- Subjects
PSYCHOLOGY ,IMMUNOLOGY ,PSYCHOLOGICAL stress ,LEUKOCYTES ,LYMPHOCYTES ,GRANULOCYTES ,PSYCHONEUROIMMUNOLOGY ,IMMUNOGLOBULINS ,SMOKING ,ADRENALINE ,ALCOHOL drinking ,HYDROCORTISONE - Abstract
Two studies are presented, both of which aimed to establish the effects of psychosocial load and symptoms on the following enumerative immunologic parameters: leucocytes, granulocytes, monocytes, lymphocytes, lymphocyte subsets, and plasma levels of IgG, IgA, and IgM. In study I, 83 and in study II, 95 subjects participated, who were selected based on their scores on questionnaires measuring daily hassles, and psychoneurotic symptoms. The following four groups were composed: (1) low load, few symptoms; (2) high load, few symptoms; (3) low load, many symptoms; (4) high load, many symptoms. The influences of the psychological variables were assessed using regression analyses, while controlling for age (study I), gender (study 2), smoking cigarettes, alcohol consumption, and plasma levels of adrenaline and cortisol. The psychological factors did not explain any of the variance in the dependent variables in either study. It is concluded that there is no relationship between the immunologic parameters under investigation and self-reports of daily hassles and symptoms. [ABSTRACT FROM AUTHOR]
- Published
- 1993
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17. Familiarity between patient and general practitioner does not influence the content of the consultation.
- Author
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Jabaaij L, Fassaert T, van Dulmen S, Timmermans A, van Essen GA, and Schellevis F
- Abstract
Background: Personal continuity in general practice is considered to be a prerequisite of high quality patient care based on shared knowledge and mutual understanding. Not much is known about how personal continuity is reflected in the content of GP -- patient communication. We explored whether personal continuity of care influences the content of communication during the consultation.Methods: Personal continuity was defined as the degree of familiarity between GP and patient, rated by both the GP and the patient. 394 videotaped consultations between GPs and patients aged 18 years and older were analyzed. GP -- patient communication was evaluated with an observation checklist, which rated the following topics of conversation: (1) medical issues, (2) psychological themes, and (3) the social environment of the patient. For each of these topics we coded whether or not it received attention, and was built upon prior knowledge. Data were analyzed using multilevel logistic regression analyses.Results: No relationship was found between GP -- patient familiarity and the discussion of medical issues, psychological themes, or the social environment of the patient. But if the patient and the GP knew each other very well, the GP more often displayed prior knowledge with the topic in question. Few patient and GP characteristics were associated with differences in content of communication.Conclusion: Given the relatively small sample size, we carefully conclude that familiarity between a GP and a patient does not influence the content of the communication (medical issues, psychological themes nor topics relating to the social environment). This is remarkable because we expected that familiarity would 'open up the communication' for more psychological and social themes. GPs seem to have the communication skills to put both familiar and non-familiar patients at ease enabling them to freely raise any issue they think necessary. [ABSTRACT FROM AUTHOR]
- Published
- 2008
18. Influence of perceived psychological stress and distress on antibody response to low dose rDNA hepatitis B vaccine
- Author
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Jabaaij, L., Grosheide, P.M., Heijtink, R.A., Duivenvoorden, H.J., Ballieux, R.E., and Vingerhoets, A.J.J.M.
- Published
- 1993
- Full Text
- View/download PDF
19. Excess of health care use in general practice and of comorbid chronic conditions in cancer patients compared to controls.
- Author
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Jabaaij L, van den Akker M, and Schellevis FG
- Subjects
- Adolescent, Adult, Age Distribution, Aged, Analysis of Variance, Comorbidity, Control Groups, Female, Humans, Male, Middle Aged, Neoplasms diagnosis, Neoplasms epidemiology, Netherlands epidemiology, Patient Discharge standards, Quality Assurance, Health Care standards, Referral and Consultation standards, Sex Distribution, Family Practice standards, Health Services Misuse statistics & numerical data, Neoplasms therapy, Practice Patterns, Physicians' standards, Quality Assurance, Health Care methods
- Abstract
Background: The number of cancer patients and the number of patients surviving initial treatments is expected to rise. Traditionally, follow-up monitoring takes place in secondary care. The contribution of general practice is less visible and not clearly defined.This study aimed to compare healthcare use in general practice of patients with cancer during the follow-up phase compared with patients without cancer. We also examined the influence of comorbid conditions on healthcare utilisation by these patients in general practice., Methods: We compared health care use of N=8,703 cancer patients with an age and gender-matched control group of patients without cancer from the same practice. Data originate from the Netherlands Information Network of General Practice (LINH), a representative network consisting of 92 general practices with 350,000 enlisted patients. Health care utilisation was assessed using data on contacts with general practice, prescription and referral rates recorded between 1/1/2001 and 31/12/2007. The existence of additional comorbid chronic conditions (ICPC coded) was taken into account., Results: Compared to matched controls, cancer patients had more contacts with their GP-practice (19.5 vs. 11.9, p<.01), more consultations with the GP (3.5 vs. 2.7, p<.01), more home visits (1.6 vs. 0.4, p<.01) and they got more medicines prescribed (18.7 vs. 11.6, p<.01) during the follow-up phase. Cancer patients more often had a chronic condition than their matched controls (52% vs. 44%, p<.01). Having a chronic condition increased health care use for both patients with and without cancer. Cancer patients with a comorbid condition had the highest health care use., Conclusion: We found that cancer patients in the follow-up phase consulted general practice more often and suffered more often from comorbid chronic conditions, compared to patients without cancer. It is expected that the number of cancer patients will rise in the years to come and that primary health care professionals will be more involved in follow-up care. Care for comorbid chronic conditions, communication between specialists and GPs, and coordination of tasks then need special attention.
- Published
- 2012
- Full Text
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20. The immunological and psychological effects of bereavement: does grief counseling really make a difference? A pilot study.
- Author
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Beem EE, Hooijkaas H, Cleiren MH, Schut HA, Garssen B, Croon MA, Jabaaij L, Goodkin K, Wind H, and de Vries MJ
- Subjects
- Aged, Cell Movement drug effects, Cell Movement immunology, Female, Follow-Up Studies, Humans, Killer Cells, Natural immunology, Killer Cells, Natural metabolism, Leukocytes, Mononuclear drug effects, Leukocytes, Mononuclear immunology, Lymphocytes drug effects, Lymphocytes immunology, Middle Aged, Phytohemagglutinins pharmacology, Pilot Projects, Pokeweed Mitogens pharmacology, Stress, Psychological therapy, Bereavement, Counseling, Stress, Psychological immunology, Stress, Psychological psychology
- Abstract
This study evaluates psychological and immunological functioning after bereavement and the influence of group counseling. Eighteen widows (bereaved within 3 months of enrolment) and a reference group of 10 married control subjects were asked to fill in self-report scales and to donate a blood sample (T1). After T1, half of the widows (the experimental group) were randomly assigned to grief counseling (13 sessions over 4 months), while the other subjects (the control group) received no treatment. Seven months after bereavement (T2) or, in the case of the experimental group, immediately after the intervention, a follow-up was conducted in the widowed subsample using the same measures. Blood samples were analyzed to determine the total number of white blood cells, number of lymphocyte subsets, natural killer cell activity (NKCA) and lymphocyte proliferative response to phytohemagglutinin (PHA), anti-CD3 and pokeweed mitogen (PWM). At T1, we found significant differences between widows and non-widows regarding both psychological and immunological measures. Widows felt more anxious, depressed, hostile and agoraphobic. At T1, widows had a lower number of the CD19+CD5+ B cell subpopulation. The cell function tests for T and B cells showed higher responses in widows (lymphocyte proliferation response to PHA, anti-CD3 and PWM). No significant difference in NKCA was found between widows and non-widows. At T2, there appeared to be no significant difference between widows and non-widows on the psychological measures. With respect to the immunological measures, widows and non-widows showed no significant differences for the total number of white blood cells, number of lymphocyte subsets and NKCA. Consistent with our findings at T1, the lymphocyte proliferation response to PHA, anti-CD3 and PWM at T2 appeared to be higher in widows than in non-widows. Comparing the experimental group (widows) and the control group (widows) with respect to psychological measures at T1, widows in the experimental group felt more insufficient and had more sleep disturbances. With respect to the immunological measures, no differences were found between those two groups. When the same two groups were again compared at T2, no differences were found in any of the psychological or immunological measures (lymphocyte sub-populations, proliferation tests and the NKCA).
- Published
- 1999
- Full Text
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21. 'Burnout' among Dutch midwives.
- Author
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Bakker RH, Groenewegen PP, Jabaaij L, Meijer W, Sixma H, and de Veer A
- Subjects
- Adaptation, Psychological, Adult, Cross-Sectional Studies, Humans, Middle Aged, Netherlands, Social Support, Surveys and Questionnaires, Burnout, Professional psychology, Nurse Midwives psychology, Private Practice
- Abstract
Objective: to determine the effect of workload on 'burnout' having considered work capacity., Design: cross-sectional study., Setting: Dutch community midwives in independent practice., Participants: 200 Dutch community midwives., Measurements: three-week diary recordings, a questionnaire on practice and personal characteristics, and a questionnaire on 'burnout', social support and coping style., Findings: differences in 'burnout' can be explained partly by the midwife's workload and partly by her work capacity. A high workload may lead to 'burnout' when a midwife is unable to handle stressful situations., Key Conclusions: when a higher percentage of the supervised births occurred at the client's own home instead of during a short-stay hospital visit, the chances of 'burnout' are lower., Implications for Practice: changes in the organisation of Dutch community midwifery care may contribute to the reduction of 'burnout'. 'Burnout' is a complex phenomenon influenced both by individual and organisational factors. When formulating policy to reduce 'burnout' among midwives specific work-related factors must be considered and emphasis be placed on the importance of personal resources.
- Published
- 1996
- Full Text
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22. Home births in The Netherlands: midwifery-related factors of influence.
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Jabaaij L and Meijer W
- Subjects
- Attitude of Health Personnel, Cross-Sectional Studies, Female, Humans, Netherlands, Nurse Midwives psychology, Nursing Evaluation Research, Pregnancy, Time Factors, Home Childbirth nursing, Nurse Midwives organization & administration, Private Practice organization & administration
- Abstract
Objective: identification of midwifery-related factors influencing the varied percentage of home births in the practice of Dutch midwives., Design: cross-sectional study., Setting: independent midwifery practices in the Netherlands., Participants: 115 independent midwives., Measurements: recordings of time spent on professional activities over three weeks. Questionnaires were completed on practice characteristics and opinion regarding the place and risks of birth., Findings: attending home births is no more time consuming for midwives than assisting at short-stay hospital births. The percentage of home births in a practice is not related to the average number of hours worked per week, nor to the size or type of practice. The percentage of home births is lowest in major cities. Midwives who think more positively about home births and do not consider these to involve greater risks assist at more home births., Implications for Practice: the assumption that a heavy workload will interfere with the policy of de-medicalising birth is found to be false. The opinion of a midwife about the desirability and safety of home confinement has a slight positive effect on the percentage of home births in her practice. Those attempting to promote an increase in births at home must take these factors into account.
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- 1996
- Full Text
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23. Modulation of immune response to rDNA hepatitis B vaccination by psychological stress.
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Jabaaij L, van Hattum J, Vingerhoets JJ, Oostveen FG, Duivenvoorden HJ, and Ballieux RE
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- Adolescent, Adult, Dose-Response Relationship, Drug, Female, Hepatitis B Surface Antigens immunology, Hepatitis B Vaccines administration & dosage, Humans, Male, Personality Inventory, Psychoneuroimmunology, Stress, Psychological immunology, Vaccines, Synthetic administration & dosage, Hepatitis B Antibodies blood, Hepatitis B Vaccines immunology, Stress, Psychological complications, Vaccines, Synthetic immunology
- Abstract
In a previous study it was shown that antibody formation after vaccination with a low-dose recombinant DNA (rDNA) hepatitis B vaccine was negatively influenced by psychological stress. The present study was designed to assess whether the same inverse relation between HBs-antibody levels and psychological stress could be observed, while administering the standard, and thus higher, dose of vaccine. Volunteers (n = 68) scoring extremely low or high on a combination of questionnaires measuring daily problems and psychoneurotic symptoms were selected for participation. Antibody levels were determined 2, 6, and 7 months after the first vaccination. Questionnaires were completed before entering the study and at month 6. In contrast to the previous study, psychological stress was not found to be related to the antibody levels at any timepoint. These results suggest that, under certain conditions, stress-induced immunomodulation in vivo might be dependent on antigen dose.
- Published
- 1996
- Full Text
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24. Self-reported stressors, symptom complaints and psychobiological functioning I: Cardiovascular stress reactivity.
- Author
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Vingerhoets AJ, Ratliff-Crain J, Jabaaij L, Menges LJ, and Baum A
- Subjects
- Adaptation, Psychological physiology, Adult, Awareness physiology, Electrocardiography, Heart Rate physiology, Humans, Life Style, Male, Middle Aged, Personality Inventory, Psychophysiologic Disorders psychology, Signal Processing, Computer-Assisted, Somatoform Disorders psychology, Stress, Psychological physiopathology, Type A Personality, Arousal physiology, Cardiovascular System innervation, Psychophysiologic Disorders physiopathology, Sick Role, Somatoform Disorders physiopathology, Stress, Psychological complications, Sympathetic Nervous System physiopathology
- Abstract
Taking into account neuroticism and lifestyle variables (smoking and alcohol consumption), cardiovascular and psychological reactions to stressful films were studied in four groups of subjects selected on self-reported levels of recent stressor load and symptom complaints (low-load/low-symptoms: low-load/high-symptoms; high-load/low-symptoms; high-load/high-symptoms). The films were known either to stimulate or to depress cardiovascular activity. The results showed that psychological reactions (distress; deactivation; openness/involvement) were associated with group membership and condition. In addition, high-symptom subjects were characterized by faster resting heart rates and smaller ECG T-wave amplitudes (TWAs), reflective of greater sympathetic tone on the myocard. Further, low-symptom subjects, in particular those labeled as stress-resistant (high-load/low-symptoms), exhibited larger myocardial responses to the cardiovascular-stimulating films than did high-symptom subjects. Low-symptom subjects showed predicted variations in physiological responses to the different films, whereas the responses by the high-symptom subjects showed lesser variation across films. It is concluded that the cardiovascular responses of low-symptom subjects more accurately followed the energetic demands of the body, whereas the high-symptom subjects were in a comparatively enduring state of arousal.
- Published
- 1996
- Full Text
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25. Self-reported stressors, symptom complaints and psychobiological functioning-II: Psychoneuroendocrine variables.
- Author
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Vingerhoets AJ, Ratliff-Crain J, Jabaaij L, Tilders FJ, Moleman P, and Menges LJ
- Subjects
- Adult, Anxiety psychology, Depression psychology, Hormones blood, Humans, Life Style, Male, Middle Aged, Personality Assessment, Psychophysiologic Disorders psychology, Self Care psychology, Sick Role, Somatoform Disorders psychology, Stress, Psychological physiopathology, Type A Personality, Arousal physiology, Neurosecretory Systems physiopathology, Psychophysiologic Disorders physiopathology, Somatoform Disorders physiopathology, Stress, Psychological complications
- Abstract
The present study examined resting endocrinological functioning and endocrine responsivity to new challenges as a function of self-reported stress load and symptomatology. Following a baseline period, four groups of male subjects (low-load/low-symptoms; low-load/high-symptoms; high-load/low-symptoms; high-load/high-symptoms) were exposed to stressful films, followed by a rest period. Blood samples were drawn after each film and after the rest condition, and urinary samples were collected during two nights preceding the experimental session. Neuroendocrine variables measured in plasma included adrenaline, noradrenaline, ACTH, cortisol, growth hormone, prolactin, and testosterone. The urinary samples were assayed for noradrenaline and adrenaline (in relation to creatinin). High-symptom subjects had significantly higher plasma levels of noradrenaline and overnight urinary adrenaline levels, whereas their cortisol levels tended to be lower as compared to the low-symptom group. The plasma noradrenaline/cortisol ratio was higher among the high-symptom subjects. However, upon controlling for neuroticism and life style factors (smoking and alcohol consumption), all but the effects on cortisol failed to meet significance criteria. Higher stress load was associated with higher plasma adrenaline responses during the laboratory session, irrespective of neuroticism or life-style measures. These results therefore suggest that in addition to measuring exposure to real-life stressors, it is also necessary to measure outcomes, such as symptoms, and to be aware of the effects of neuroticism and life-style when attempting to understand which specific psychosocial factors effect psychoendocrinological functioning.
- Published
- 1996
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26. Immunologic, endocrine and psychological influences on cortisol-induced immunoglobulin synthesis in vitro.
- Author
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Jabaaij L, Benschop RJ, Oostveen FG, Duivenvoorden HJ, Vingerhoets JJ, and Ballieux RE
- Subjects
- Adult, Arousal drug effects, Cells, Cultured, Dose-Response Relationship, Drug, Female, Humans, Hydrocortisone pharmacology, Male, Monocytes drug effects, Psychoneuroimmunology, Arousal physiology, Hydrocortisone blood, Immunoglobulin G biosynthesis, Immunoglobulin M biosynthesis, Monocytes immunology
- Abstract
In the present study, the relationship between psychological variables and hydrocortisone (HC)-induced immunoglobulin (Ig) production in vitro was investigated. Ninety-five human volunteers were selected based on their extreme (low or high) scores on a daily hassles and a symptoms questionnaire. Four groups were composed: (1) few hassles, few symptoms; (2) many hassles, few symptoms; (3) few hassles, many symptoms; and (4) many hassles, many symptoms. Incubating peripheral blood mononuclear cells (PBMC) for 2 weeks with HC (concentrations ranging from 10(-8) to 10(-6) M), resulted in a concentration-dependent rise in IgM and IgG secretion. In vitro IgM as well as IgG secretion were found to be related to plasma Ig levels. Plasma cortisol levels were positively associated with HC-induced IgG secretion. Furthermore, Ig secretion was found to depend on psychological profile, indicating a differential sensitivity of PBMC to HC for the four groups.
- Published
- 1993
- Full Text
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27. Psychobiological factors related to human natural killer cell activity and hormonal modulation of NK cells in vitro.
- Author
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Benschop RJ, Jabaaij L, Oostveen FG, Vingerhoets AJ, Kirschbaum C, Duivenvoorden HJ, and Ballieux RE
- Subjects
- Adolescent, Adult, Cyclic AMP blood, Cytotoxicity Tests, Immunologic, Epinephrine blood, Female, Hormones blood, Humans, Hydrocortisone blood, In Vitro Techniques, Killer Cells, Natural metabolism, Male, Stress, Psychological metabolism, Hormones metabolism, Killer Cells, Natural physiology, Stress, Psychological immunology
- Abstract
The present report investigated whether percentages of circulating natural killer (NK) cells and NK cell activity (NKCA) are associated with psychological variables. Subjects (n = 95) were selected, based on a combination of low or high scores on questionnaires on daily hassles and self-reported symptoms, to create four extreme groups. NK cell percentages were different between two of the four groups, only when the analysis was not controlled for gender, life style and endocrine parameters. No evidence was found for a relationship between group membership and NKCA. NKCA, however, was found to differ between men and women and to be associated with percentages of NK cells and intracellular levels of cAMP. Furthermore, the hypothesis was tested, that hormone-induced changes in NKCA in vitro are dependent on the individual's current stress profile. To investigate this issue, NKCA was measured after cells had been incubated with hydrocortisone (10(-6) or 10(-7) M) or the beta-adrenergic agonist isoprenaline (10(-5) or 10(-7) M) in vitro. Changes in NKCA were found to be related to plasma adrenaline levels, but no evidence was found for involvement of psychological variables. It is concluded that, in the current setting, there is no association between the combination of scores on the two psychological questionnaires, and NKCA or hormone-induced changes therein.
- Published
- 1993
- Full Text
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28. Conditioning of drug-induced immunomodulation in human volunteers: a European collaborative study.
- Author
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Kirschbaum C, Jabaaij L, Buske-Kirschbaum A, Hennig J, Blom M, Dorst K, Bauch J, DiPauli R, Schmitz G, and Ballieux R
- Subjects
- Adult, Catecholamines blood, Central Nervous System physiology, Endocrine Glands physiology, Female, Humans, Immune System physiology, Killer Cells, Natural metabolism, Male, Monocytes, Research Design, Conditioning, Classical physiology, Epinephrine administration & dosage, Killer Cells, Natural immunology, Neuroimmunomodulation physiology
- Abstract
Although several studies on conditioning of the immune system in animals have been published, no comparable data on human research have been available in the past. The present paper presents results of conditioning studies in volunteers performed in two research centres, namely the University of Trier (Germany) and the University of Utrecht (The Netherlands). After administration of a neutral stimulus (conditioned stimulus: CS), subjects were injected with epinephrine (unconditioned stimulus) for three or four days (depending on study). Subcutaneous injection of epinephrine caused a rapid enhancement of the activity of natural killer cells (NKCA) in venous blood, which was chosen as the unconditioned response. On the test trial, when saline instead of epinephrine was injected, the Trier group found a conditional enhancement of NKCA. No changes in NKCA were found in the control subjects, who received saline injections on all days along with the CS. The Utrecht group tried to replicate these results using a slightly different design. After obtaining non-confirmative results, the Utrecht experimenters tried to parallel the experimental settings of the Trier group as closely as possible. However, once again they failed to replicate the results of the Trier group. Possible reasons for the different results obtained in the two research groups are discussed.
- Published
- 1992
- Full Text
- View/download PDF
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