Biomedical subjects

M Lekander

Publications and source records attributed to M Lekander.

10 recordsLinked to original sources

PubMed2006

Changes in immune regulation in response to examination stress in atopic and healthy individuals.

BACKGROUND: Stress can aggravate the allergic inflammation, but determinants of disturbed immune regulation are largely unknown. OBJECTIVE: To determine systemic immunological, local inflammatory and functional airway responses to stress in healthy and atopic individuals. METHODS: Forty-one undergraduate students, 22 with allergy of whom 16 had asthma, and 19 healthy controls, were studied in a low-stress period and in association with a large exam. Subjects completed questionnaires on stress and health behaviours, underwent lung function tests, bronchial methacholine challenge, measurements of exhaled nitric oxide and urine cortisol. Blood cells were phenotyped, and cytokines from mononuclear blood cells were analysed. RESULTS: Perceived stress and anxiety increased in both groups during the exam period while cortisol increased only in the atopy group. Cytokine production decreased broadly in response to stress in both groups, which was paralleled by an increase in the proportion of regulatory T cells (CD4(+)CD45RO(+)CD25(bright)). Interestingly, atopic individuals, but not controls, reacted with a decreased T-helper type 1/T-helper type 2 (Th1/Th2) ratio and a decrease in natural killer (NK) cell numbers in response to stress. In control subjects only, exhaled nitric oxide decreased and forced expiratory volume in one second increased during stress. CONCLUSION: Atopic and non-atopic subjects shared some immune changes in response to stress, such as a dramatic decline in cytokines and an increase in the number of regulatory T cells in peripheral blood. However, other stress-induced immune changes were unique to atopic individuals, such as a skewed Th1/Th2 ratio and reduced NK cell numbers, indicating that some pathogenic mechanisms in atopics may be more strongly affected by stress than others.

Adult↗

PubMed2005

Support group for cancer patients. Does it improve their physical and psychological wellbeing? A pilot study.

In order to evaluate a structured support intervention programme, symptoms and quality of life (QOL) were studied in 61 consecutive cancer patients with different tumour diagnoses in relation to intervention and follow-up. The majority of the patients were female. The Edmonton symptom assessment scale (ESAS), the Norwegian fatigue questionnaire and the hospital anxiety and depression scale (HADS) were used. Data were analysed according to ANOVA and Tukey's honest significant difference (HSD) test. ESAS sickness score (P=0.0001), depression (P=0.0001), anxiety (P=0.0001) and QOL (P=0.0009) improved and the improvements in depression and anxiety were still significant after 3 months (P=0.02 respectively). Aspects of fatigue also improved significantly in 7 of 11 questions after the intervention (P< or =0.04) but these improvements were not observed after 3 months. Anxiety according to the HADS questionnaire improved significantly after the intervention (P=0.0006). The majority of the patients highly appreciated the possibility of sharing thoughts and troubles with others with similar experiences (59%). The programme was therefore found to improve QOL, and physical and psychological functions. Randomized studies in relation to immunological changes and follow-up are in progress.

Adaptation, Psychological↗

PubMed2004

Inflammatory markers and heart rate variability in women with coronary heart disease.

PURPOSE: Both heart rate variability (HRV) and inflammatory markers are carrying prognostic information in coronary heart disease (CHD), however, we know of no studies examining their relation in CHD. The aim of this study, therefore, was to assess the association between HRV and inflammatory activity, as reflected by the levels of interleukin-6 (IL-6), IL-1 receptor antagonist (IL-1ra) and C-reactive protein (CRP). SUBJECTS AND METHODS: Consecutive women patients who survived hospitalization for acute myocardial infarction, and/or underwent a percutaneous transluminal coronary angioplasty or a coronary artery bypass grafting were included and evaluated in a stable condition 1 year after the index events. An ambulatory 24-h ECG was recorded during normal activities. SDNN index (mean of the standard deviations of all normal to normal intervals for all 5-min segments of the entire recording) and the following frequency domain parameters were assessed: total power, high frequency (HF) power, low frequency (LF) power and very low frequency (VLF) power. Levels of high-sensitivity CRP were measured by nephelometry, IL-6 and IL-1ra concentrations were determined by enzyme immunoassay. RESULTS: Levels of IL-6 showed an inverse relation with HRV measures even after controlling for potential confounding factors. The P-values were 0.02, 0.04, 0.01, 0.03, 0.18 for the multivariate association with SDDN index, total power, VLF power, LF power and HF power respectively. In contrast, the inverse relationship between HRV measures and CRP or IL-1ra levels were weak and nonsignificant. Correlation coefficients for the relationship between IL-6 and HRV measures were both uni- and multivariately higher than for the relationship between HRV measures and any other factors evaluated in this study. CONCLUSION: Concentration of IL-6 showed a negative, independent association with HRV in women with CHD. Thus, increased inflammatory activity, as reflected by IL-6 levels, may represent a new auxiliary mechanism linking decreased HRV to poor prognosis in CHD.

Adult↗

PubMed2000

Neuroimmune relations in patients with fibromyalgia: a positron emission tomography study.

To study relations between neural and immune activity in patients with chronic pain, we correlated regional cerebral blood flow measured with [(15)O]butanol positron emission tomography to immune function in five patients with fibromyalgia. Partly replicating previous data in healthy volunteers, natural killer cell activity correlated negatively with right hemisphere activity in the secondary somatosensory and motor cortices as well as the thalamus. Moreover, natural killer cell activity was negatively and bilaterally related to activity in the posterior cingulate cortex. Thus, immune parameters were related to activity in brain areas involved in pain perception, emotion, and attention. Implicated from a small study population, these strong neuro-immune associations are discussed in view of recent findings concerning mechanisms and adaptive values in immuno-cortical communication and regulation.

Adult↗

PubMed1999

[The immune system is affected by psychological factors. High stress levels can change susceptibility to infection and allergy].

The article consists in a review of the evidence of psychological and neural influences on the aetiology and severity of allergy. Histamine release in response to symbolic stimuli and behavioural conditioning of allergy-related immune variables suggest the existence of links via which psychological factors can affect the allergic cascade. Although this has been established in animal species, and is supported by evidence of neuro-immune communication pathways, convincing evidence of its occurrence in humans is sparse. Although asthma and stress symptoms seem to be related, the causal direction of such relationship remains unclear. In view of the occurrence of undocumented allergy and the importance of symptom perception as a basis for optimal medication, the assessment of subjective allergy symptoms is a cogent issue.

Animals↗

PubMed1998

Human brain-immune relationships: a PET study.

To study brain-immune relations, we correlated positron emission tomographic (PET) measures of regional cerebral blood flow (rCBF) with immune measures in 10 female volunteers. The natural killer (NK) activity correlated negatively with activity bilaterally in the secondary sensory cortex, whereas the Concanavalin A (Con A) response correlated positively with rCBF bilaterally in secondary visual, motor, and sensory cortices, the thalamus, the putamen, and the left hippocampus. Although representing preliminary data from a small number of subjects, these observations provide further support for the presence of interactions between the brain and the immune system.

Adult↗

PubMed1997

Immune effects of relaxation during chemotherapy for ovarian cancer.

BACKGROUND: Psychological interventions, such as relaxation training, have been applied to strengthen resistance to disease. There is evidence that relaxation can modify immune parameters in healthy populations and in chemotherapy naive cancer patients. METHODS: In this study, 22 patients receiving chemotherapy for ovarian cancer were allocated to relaxation training with a clinical psychologist or to a control group. After 2 months' training, blood was sampled 2 days before chemotherapy in the patients' homes, and at the hospital prior to treatment. RESULTS: On average, the intervention group showed higher lymphocyte counts, and a tendency to higher white blood cell numbers as compared to the control group. No significant effects were found in proliferative responses to mitogen and natural killer cell activity after intervention. Relaxation training did not modify the magnitude of changes in immune variables between home samples and at the hospital in anticipation of treatment. CONCLUSIONS: The study suggests that relaxation training can positively affect immune parameters in cancer patients, even if training is performed during myelosuppressive therapy.

Adult↗

PubMed1996

Social support and immune status during and after chemotherapy for breast cancer.

Social support and immune status were assessed in women treated with adjuvant chemotherapy for breast cancer. Perception of enhanced attachment was associated with an increased number of white blood cell levels three months after, but not during, chemotherapy. After treatment, patients with high attachment ratings had higher numbers and proportions of granulocytes, and lower proportions of lymphocytes and monocytes. It is concluded that the support experienced by a cancer patient can be associated with counts and proportions of leukocytes, but that this effect, if present during chemotherapy, is overridden by the biological factor that affects the haematopoetic process.

Age Factors↗

PubMed1995

Anticipatory immune changes in women treated with chemotherapy for ovarian cancer.

Immune parameters were assessed in 22 women before chemotherapy for ovarian cancer and compared with assessment made at home 2 days earlier. In the hospital, as compared to home measures, patients had a lower percentage of lymphocytes and monocytes and a higher percentage of granulocytes. Absolute numbers of lymphocytes were lower at the hospital as compared to at home. T-cell proliferative responses to concanavalin A were elevated for cells isolated from hospital blood samples as compared to home samples. The observed changes in immune parameters were not related to levels o r state anxiety at home or at the hospital. The results show anticipatory immune changes in a group of patients receiving chemotherapy that did not include cyclophosphamide.

Journal Article↗

PubMed1993

Trait anxiety and anticipatory immune reactions in women receiving adjuvant chemotherapy for breast cancer.

We compared peripheral blood cell counts as well as mitogen activity and natural killer-cell activity in women undergoing adjuvant chemotherapy for breast cancer in the hospital prior to chemotherapy with assessment at home 2 days earlier. Patients compared to controls had an increased number of white blood cell counts in the hospital as compared to those at home, mediated by an increased total number of granulocytes. Among patients, those with high compared to low trait anxiety evidenced immune system changes. Total number of monocytes were reduced in patients with high compared to low trait anxiety and natural killer-cell activity tended to be compromised in the high anxiety group. Helper/inducer T-cells isolated from hospital blood samples were lower in patients with high as compared to low trait anxiety, while no difference was observed in samples taken at home. Conditioned nausea was associated with trait anxiety and patients with as compared to without conditioned nausea displayed immune changes similar to changes observed as a function of trait anxiety. State anxiety measured at the hospital did not relate to immune measures. The observed increase in granulocytes is consistent with an interpretation both in terms of conditioning and anticipatory stress. The anticipatory immunosuppression in patients with high compared to low trait anxiety is consistent with the hypothesis that chemotherapy patients may develop conditioned immunosuppression after repeated pairings of treatment-related stimuli with the unconditioned immunosuppressive effect of chemotherapy.

Adult↗