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Biomedical subjects

H Karlsson

Publications and source records attributed to H Karlsson.

At least 19 recordsLinked to original sources

Increased levels of circulating soluble CD14 but not CD83 in infants are associated with early intestinal colonization with Staphylococcus aureus.

BACKGROUND: Soluble forms of the monocyte marker CD14 and the mature dendritic cell marker CD83 are plasma proteins with immunoregulatory functions. The physiological stimulus for their production is unclear and their possible role in allergy development is unknown. METHODS: We measured the plasma levels of soluble CD14 (sCD14) and soluble CD83 (sCD83) in 64 Swedish children in relation to intestinal bacterial colonization pattern in a prospective birth cohort. Soluble CD14 and sCD83 levels were quantified by enzyme linked immunosorbent assay in plasma obtained at birth and at 4, 18 and 36 months of age. All major aerobic and anaerobic bacteria were quantified in faecal samples obtained regularly over the first 8 weeks of life. Clinical allergy and IgE levels were evaluated at 18 months of age. RESULTS: Soluble CD14 in plasma increased during the first 18 months of life while sCD83 peaked at 4 months of age. Children who were perinatally colonized with Staphylococcus aureus had significantly higher levels of sCD14 in plasma at 4 months of age relative to non-colonized children. The levels of sCD14 were unrelated to colonization with Escherichia coli, other enterobacteria, enterococci, clostridia, Bacteroides, bifidobacteria or lactobacilli. Further, children with food allergy by 18 months tended to have lower levels of sCD14 than healthy children. Plasma levels of sCD83 were not related to either bacterial colonization pattern or allergy development. CONCLUSIONS: Perinatal colonization with S. aureus may trigger the occurrence of sCD14 in plasma, which may influence development of the infantile immune system and risk of allergy development.

Antigens, CD↗

Influenza A virus infection causes alterations in expression of synaptic regulatory genes combined with changes in cognitive and emotional behaviors in mice.

Epidemiological studies have indicated a link between certain neuropsychiatric diseases and exposure to viral infections. In order to examine long-term effects on behavior and gene expression in the brain of one candidate virus, we have used a model involving olfactory bulb injection of the neuro-adapted influenza A virus strain, WSN/33, in C57Bl/6 mice. Following this olfactory route of invasion, the virus targets neurons in the medial habenular, midline thalamic and hypothalamic nuclei as well as monoaminergic neurons in the brainstem. The mice survive and the viral infection is cleared from the brain within 12 days. When tested 14-20 weeks after infection, the mice displayed decreased anxiety in the elevated plus-maze and impaired spatial learning in the Morris water maze test. Elevated transcriptional activity of two genes encoding synaptic regulatory proteins, regulator of G-protein signaling 4 and calcium/calmodulin-dependent protein kinase IIalpha, was found in the amygdala, hypothalamus and cerebellum. It is of particular interest that the gene encoding RGS4, which has been related to schizophrenia, showed the most pronounced alteration. This study indicates that a transient influenza virus infection can cause persistent changes in emotional and cognitive functions as well as alterations in the expression of genes involved in the regulation of synaptic activities.

Animals↗

Cat allergen induces proinflammatory responses by human monocyte-derived macrophages but not by dendritic cells.

BACKGROUND: The upper airway mucosa of healthy humans contains a dense network of cells with dendritic morphology of which the majority express a macrophage-like phenotype (CD14+CD64+CD68+), whereas the smaller population are immature dendritic cells (DC; CD11c+CD14-). Our aim was to study the proinflammatory response of human monocytes and in vitro-generated macrophages and DC after contact with cat allergens. METHODS: Monocyte-derived DC and monocyte-derived macrophages were exposed to cat allergen extract or Escherichia coli. Purified monocytes were stimulated with allergen extracts from cat or house dust mite (HDM) or the major allergenic protein Fel d 1 and induction of proinflammatory cytokines by monocytes was analyzed before and after blocking CD14. RESULTS: We show that cat allergen extract induced tumor necrosis factor (TNF) and interleukin (IL)-6 production by CD14-positive macrophages but not by CD14-negative DC. Moreover, monocytes produced significantly higher levels of TNF in response to cat allergens than in response to HDM allergens. We observed no differences in levels of TNF and IL-6 from either macrophages or monocytes after exposure to cat allergen when comparing healthy and cat-allergic individuals. Finally, the proinflammatory cytokine production from monocytes in response to cat allergen extract but not to HDM allergen was significantly reduced by blocking CD14. CONCLUSION: These results indicate that closely related innate immune cells from the myeloid lineage respond differentially to cat allergen extract and that the pattern-recognition receptor CD14 might be one of the mediators involved in the inflammatory responses to inhalant allergens.

Adult↗

Temperature variation in newborn babies: importance of physical contact with the mother.

BACKGROUND: Hypothermia is a major cause of deterioration and death in the neonatal period. Temperature deviations are key signs of illness. OBJECTIVE: To determine normal patterns of temperature variation in newborn babies and the influence of external factors. METHODS: Abdominal and foot skin temperature were continuously recorded in 27 healthy full term babies during the first two days of life and related to the care situation-that is, whether the baby was with the mother or in its cot. The recordings were made using no wires to avoid interference with the care of the neonate. Ambient temperature was close to 23 degrees C during the study period. RESULTS: Mean rectal and abdominal and foot skin temperature were lower on day 1 than day 2. The foot skin temperature was directly related to the care situation, being significantly higher when the baby was with the mother. The abdominal skin temperature was much less influenced by external factors. When the neonates were with their mothers, the mean difference between rectal temperature and abdominal skin temperature was 0.2 degrees C compared with a mean difference between rectal temperature and foot skin temperature of 1.5 degrees C, indicating a positive heat balance. In the cot the corresponding temperature differences were 0.7 degrees C and 7.5 degrees C. A temperature difference between rectal and foot skin temperature of 7-8 degrees C indicates a heat loss close to the maximum for which a neonate can compensate (about 70 W/m2). CONCLUSION: This study emphasises the importance of close physical contact with the mothers for temperature regulation during the first few postnatal days.

Body Temperature↗

Effects of the brominated flame retardants hexabromocyclododecane (HBCDD), and tetrabromobisphenol A (TBBPA), on hepatic enzymes and other biomarkers in juvenile rainbow trout and feral eelpout.

Brominated flame retardants (BFRs) leak out in the environment, including the aquatic one. Despite this, sublethal effects of these chemicals are poorly investigated in fish. In this study, a screening of selected biomarkers in juvenile rainbow trout (Oncorhynchus mykiss) and feral eelpout (Zoarces viviparus) was performed after exposure to hexabromocyclododecane (HBCDD) and tetrabromobisphenol A (TBBPA). Rainbow trout was injected intraperitoneally (i.p.) with HBCDD or TBBPA. Two out of four short-term experiments with HBCDD showed an increase in the activity of catalase. A 40% increase in liver somatic index (LSI) could be observed after 28 days. HBCDD did also seem to have an inhibitory effect on CYP1A's activity (ethoxyresorufin-O-deethylase (EROD)). A putative peroxisome proliferating activity of the compound was investigated without giving a definite answer. HBCDD did not seem to be estrogenic or genotoxic. TBBPA increased the activity of glutathione reductase (GR) after 4, 14 and 28 days in rainbow trout suggesting a possible role of this compound in inducing oxidative stress. The compound did not seem to be estrogenic. TBBPA seemed to compete with the artificial substrate ethoxyresorufin in vitro, during the EROD assay. In eelpout, only one 5 days in vivo experiment was performed. Neither of the compounds gave rise to any effect in this fish. This was the first screening of sublethal effects of the two chemicals in fish, using high doses. Our results indicate that there is a need for further studies of long-term, low-dose effects of these two widely used flame retardants.

Animals↗

Psychodynamic personality profile in first-episode severe mental disorders.

OBJECTIVE: The aim of this study was to relate measures of psychoanalytically derived personality traits to descriptive diagnosis and psychopathology in severe mental disorders. METHOD: Sixty-one consecutive first-episode patients with schizophrenia, bipolar disorder and severe major depression were interviewed. Personality traits were assessed with the Karolinska Psychodynamic Profile (KAPP) and compared with the DSM-IV diagnosis and symptom clusters derived from the BPRS. RESULTS: There were no marked differences in personality traits between the three diagnostic groups, between schizophrenia and affective disorders or between psychotic and non-psychotic illness. However, personality traits had significant associations with symptoms, especially with the emotional retardation cluster. CONCLUSION: Our findings do not support the hypothesis that severe mental disorders would differ from each other in terms of long-standing psychodynamic personality profiles. Certain dysfunctional personality traits may predict especially negative emotional symptoms and possibly also predispose a person to them.

Adult↗

Neuroanatomical substrata of amusement and sadness: a PET activation study using film stimuli.

The aim of the present study was to explore the neuroanatomical substrata of film-induced amusement and sadness, aiming at maximal reliability by using strict statistics. Film-induced changes in regional cerebral blood flow (rCBF) were measured using positron emission tomography and [15O]water. It appeared that many brain regions were involved similarly and symmetrically in both emotions. Activation of the occipitotemporal and anterior temporal cortex and cerebellum during both emotions agreed well with the earlier findings. Contrary to some earlier studies, the posterior cingulate gyrus and some frontal areas were deactivated in both emotions. The strict explorative analysis did not reveal activations in the limbic or subcorticai structures seen in some earlier studies. However, an additional analysis restricted to the subcortical and limbic system structures revealed bilateral activation of the amygdala in both target emotions. The outcomes of imaginal studies of emotions seem to be largely dependent on the conservativeness of the statistical analysis and very likely also on the method of emotion induction.

Adult↗

Severe somatization in women is associated with altered cerebral glucose metabolism.

BACKGROUND: Somatization is a clinical phenomenon characterized by multiple, medically unexplained somatic symptoms. The pathophysiology remains unknown. We aimed to test the hypothesis of a central nervous system dysfunction in the pathophysiology of this disorder. METHOD: We studied 10 female patients diagnosed as having somatization disorder or undifferentiated somatoform disorder with no current Axis I disorders according to DSM-IV. They were compared with 17 healthy female volunteers using brain [18F]-fluorodeoxyglucose-PET with MRI reference. RESULTS: The patients had lower cerebral metabolism rates of glucose (P<0.05) in both caudate nuclei, left putamen and right precentral gyrus compared with healthy volunteers. CONCLUSIONS: This is the first study to demonstrate changes in brain metabolism in somatizing women. The regional cerebral hypometabolism is probably associated with the pathophysiology of somatization.

Adult↗

Tricyclic antidepressants prevent the differentiation of monocytes into macrophage-like cells in vitro.

The investigation was designed to determine whether the two tricyclic antidepressant agents (TCAs) clomipramine and imipramine and the selective reuptake inhibitor citalopram affect differentiation of human monocytes to macrophage-like cells (MAC-LCs). We established primary adherent cultures of peripheral blood monocytes and monitored their morphology, capacity for phagocytosis and antigen expression during transformation to MAC-LCs. As expected, maturation of monocytes to MACs is accompanied by changes in morphology, elevated expression of the antigens CD16 and CD51 and an increase in the percentage of phagocytic cells. Treatment of cells with the TCAs clomipramine (40 micromol/L) or imipramine (100 micromol/L) and with citalopram (100 micromol/L), for 11 days resulted in the following observations: (1) monocytes treated with TCAs never developed the morphology characteristic of the MAC-LCs; (2) TCAs reduced the percentage of phagocytic cells; (3) TCAs had little influence on the expression of CD14, CD16, CD51, and HLA-DR. However, when added after monocyte differentiation into MAC-LCs, citalopram and clomipramine no longer reduced the percentage of phagocytic cells and these effects were not simply due to irreversible cytotoxicity. Thus clomipramine, imipramine, and citalopram inhibit differentiation of human monocytes into MAC-LCs in vitro, but in a reversible manner.

Antidepressive Agents, Tricyclic↗

Cognitive functioning in severe somatization--a pilot study.

OBJECTIVE: Somatizing patients often report cognitive complaints but neuropsychological research on somatization is scarce. We investigated somatizing patients for functioning in different cognitive domains. METHOD: Ten female patients with somatization disorder or undifferentiated somatoform disorder and 10 non-somatizing controls participated in neuropsychological examinations. RESULTS: The patients performed at a lower level than the controls in tests involving semantic memory, verbal episodic memory and visuo-spatial tasks, and were slower in attentional tasks. CONCLUSION: Somatization patients may suffer from substantial problems in cognitive performance.

Adult↗

Structural magnetic resonance imaging in patients with first-episode schizophrenia, psychotic and severe non-psychotic depression and healthy controls. Results of the schizophrenia and affective psychoses (SAP) project.

BACKGROUND: Structural brain abnormalities are prevalent in patients with schizophrenia and affective disorders. AIMS: To study how regional brain volumes and their ratios differ between patients with schizophrenia, psychotic depression, severe non-psychotic depression and healthy controls. METHOD: Magnetic resonance imaging scans of the brain on first-episode patients and on healthy controls. RESULTS: Patients with schizophrenia had a smaller left frontal grey matter volume than the other three groups. Patients with psychotic depression had larger ventricular and posterior sulcal cerebrospinal fluid (CSF) volumes than controls. Patients with depression had larger white matter volumes than the other patients. CONCLUSIONS: Left frontal lobe, especially its grey matter volume, seems to be specifically reduced in first-episode schizophrenia. Enlarged cerebral ventricles and sulcal CSF volumes are prevalent in psychotic depression. Preserved or expanded white matter is typical of non-psychotic depression.

Adult↗

Retroviral RNA identified in the cerebrospinal fluids and brains of individuals with schizophrenia.

Schizophrenia is a serious brain disease of uncertain etiology. A role for retroviruses in the etiopathogenesis of some cases of schizophrenia has been postulated on the basis of clinical and epidemiological observations. We found sequences homologous to retroviral pol genes in the cell-free cerebrospinal fluids (CSFs) of 10 of 35 (29%) individuals with recent-onset schizophrenia or schizoaffective disorder. Retroviral sequences also were identified in the CSFs of 1 of 20 individuals with chronic schizophrenia. However, retroviral sequences were not identified in any of the CSFs obtained from 22 individuals with noninflammatory neurological diseases or from 30 individuals without evidence of neurological or psychiatric diseases (chi(2) = 19.25, P < 0.001). The nucleotide sequences identified in the CSFs of the individuals with schizophrenia or schizoaffective disorder were related to those of the human endogenous retroviral (HERV)-W family of endogenous retroviruses and to other retroviruses in the murine leukemia virus genus. Transcription of RNA homologous to members of the HERV-W family of retroviruses also was found to be up-regulated differentially in the frontal cortex regions of brains obtained postmortem from individuals with schizophrenia, as compared with corresponding tissue from individuals without psychiatric diseases. The transcriptional activation of certain retroviral elements within the central nervous system may be associated with the development of schizophrenia in at least some individuals. The further characterization of retroviral elements within the central nervous system of individuals with schizophrenia might lead to improved methods for the diagnosis and management of this disorder.

Adult↗

An historical record of toxaphene and its congeners in a remote lake in western Europe.

Historical trends in the concentrations of toxaphene, its component homologue groups, and individual chlorobornane congeners were determined in a dated sediment core from a mountain lake, Lochnagar, in Scotland, U.K., representing the first such profiles outside of North America. The profile of total toxaphene showed a bimodal distribution with maxima in the mid-1970s and early 1990s unlike the unimodal PCB profile (maximum 1973) in the same core. The earlier toxaphene peak shows agreement with the U.S. source curve and therefore may correspond to modeled global patterns while the later peak may be dueto long-rangetransportfrom eastern and southern Europe or from still lower latitudes. Sediment toxaphene concentrations (14 ng/g dry wt (dw) at surface; 40 ng/g dw at maximum) and accumulation rates (surface 0.42 ng cm(-2) yr(-1); maximum 1.6 ng cm(-2) yr(-1)) were considerably higher than levels in untreated sites in the Great Lakes region and the Canadian Arctic and are equivalent to those reported for the Great Lakes themselves where there have been additional riverine inputs. Two toxaphene congeners, B6-923 and B7-1001, accounted for most of the hexa- and heptachlorobornanes, respectively. B6-923 and B7-1001 abundance ratios (relative to the sum of 12 chlorobornane congeners) had doubling times of 17 +/- 3 and 12 +/- 3 yr, respectively. Given the remoteness of the site from areas of toxaphene production and usage, the high sediment levels raise concerns over toxaphene levels in areas of Europe closer to sources, especially where sites are fished for human consumption. Further European data are needed for comparison.

Animals↗

The Nordic Study on schizophrenic patients living in the community. Subjective needs and perceived help.

In a community sample of 418 persons diagnosed with schizophrenia, subjective needs and perceived help was measured by the Camberwell Assessment of Need (CAN). The mean number of reported needs was 6.2 and the mean number of unmet needs 2.6. The prevalence of needs varied substantially between the need areas from 3.6% ('telephone') to 84.0% ('psychotic symptoms'). The rate of satisfaction estimated as the percentage of persons satisfied with the help provided within an area varied between 20.0% ('telephone') and 80.6% ('food'). The need areas concerning social and interpersonal functioning demonstrated the highest proportion of unmet to total needs. In a majority of need areas the patients received more help from services than from relatives, but in the areas of social relations the informal network provided substantial help. In general the patients reported a need for help from services clearly exceeding the actual amount of help received. In a linear regression model symptom load (BPRS) and impaired functioning (GAF) were significant predictors of the need status, explaining 30% of the variance in total needs and 20% of the variance in unmet needs. It is concluded that the mental health system fails to detect and alleviate needs in several areas of major importance to schizophrenic patients. Enhanced collaboration between the care system and the informal network to systematically map the need profile of the patients seems necessary to minimise the gap between perceived needs and received help.

Activities of Daily Living↗

Comparison of clinical and best-estimate research DSM-IV diagnoses in a Finnish sample of first-admission psychosis and severe affective disorder.

The purpose of this study was to investigate diagnostic agreement between clinicians and a research group in a sample of first-admission psychosis and severe affective disorder patients. Clinical DSM-IV discharge diagnoses and best-estimate DSM-IV research diagnoses were compared in 116 first-episode patients in the city of Turku, Finland. The best-estimate research diagnoses were made at consensus meetings by integrating longitudinal data; patients' medical records; and findings of a clinical interview, the structured SCAN-interview, and symptom severity ratings. Overall diagnostic agreement was moderate, with a kappa value 0.51 (95% confidence interval (CI), 0.39- 0.63). Of the diagnostic groups, schizophrenic disorders had the lowest kappa value of 0.44 (95% CI, 0.26-0.63). Clinicians had a tendency to miss depressive symptoms in psychotic patients; to overdiagnose psychotic symptoms in depressive patients; and to fail to discover earlier hypomanic or depressive episodes in depressive patients. In conclusion, hospital diagnoses were not reliable in first-episode patients. Inappropriate diagnoses may compromise both treatment and epidemiologic findings based on discharge diagnoses.

Adolescent↗