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Hasse Karlsson

Publications and source records attributed to Hasse Karlsson.

At least 19 recordsLinked to original sources
PubMed2006

Characterization of the outer membrane protein profile from disease-related Helicobacter pylori isolates by subcellular fractionation and nano-LC FT-ICR MS analysis.

Because of the important role of membrane proteins in adhesion, invasion, and intracellular survival of pathogens in the host, membrane proteins are of potential interest in the search for drug targets or biomarkers. We have established a mass spectrometry-based method that allows characterization of the outer membrane protein (OMP) profile of clinical isolates from of the human gastric pathogen Helicobacter pylori. Subcellular fractionation and one-dimensional gel electrophoresis (1D-GE) analysis was combined with nano-liquid chromatography Fourier transform-ion cyclotron resonance mass spectrometry (nano-LC FT-ICR MS) and tandem mass spectrometry (MS/MS) analysis of fifteen H. pylori strains associated either with duodenal ulcers, gastric cancer, or isolated from asymptomatic H. pylori infected carriers. Over 60 unique membrane or membrane-associated proteins, including 30 of the 33 theoretically predicted OMPs, were identified from the strains. Several membrane proteins, including Omp11 and BabA, were found to be expressed by all strains. In the search for clinical markers we found that Omp26 was expressed by all disease-related strains but was only present in one out of five strains from asymptomatic carriers, which makes Omp26 a potential target for further investigation in the search for proteins unique to disease-related H. pylori strains. In addition, presence of Omp30 and absence of Omp6 seemed to be associated with H. pylori strains causing duodenal ulcer.

Amino Acid Sequence↗
PubMed2006

Psychotism and its dimensions in primary care. Associations with patient's background and manic and depressive symptoms. Results of the RADEP study.

Dimensions of psychotism have mainly been studied in clinical samples. We studied psychotism, its dimensions and their associations, in a primary care sample. In all, 1199 primary care patients over 18 years of age filled in a questionnaire including lists of psychotic (the Composite International Diagnostic Interview, CIDI), depressive (the Depression Scale, DEPS) and manic (the Mood Disorder Questionnaire, MDQ) symptoms. Psychotic symptoms were factored, and variance in factor scores was explained by patients' background and by depressive and manic symptoms. In the principal component solution, the first factor explained 22% of the total variance in psychotic (CIDI) symptoms and was named global psychotism. Varimax rotation produced seven interpretable dimensions: Schneiderian (9.7% of variance), passivity (8.9%), hallucinatory (8.5%), paranoid (7.7%), infidelity (7.6%), somatic (7.6%) and reference experiences (5.9%). Together they explained 52% of the total variance of CIDI symptoms. Global psychotism (P=0.000), as well as hallucinatory (P=0.003), paranoid (P=0.000) and infidelity (P=0.000) experiences associated inversely with age. Otherwise, patients' background associated differently with global psychotism and with factor dimensions in CIDI symptoms. Manic symptoms associated with global psychotism and with all CIDI dimensions, whereas depressive symptoms associated with global psychotism, passivity, paranoid and infidelity experiences. Psychotism is composed of a global factor and of independent dimensions, and is more prevalent in young people. Independently of patients' background, manic widely and depressive symptoms less widely associate with occurrence of psychotism.

Adult↗
PubMed2006

Brain glucose metabolism and temperament in relation to severe somatization.

Little is known about the pathophysiology of somatization. The authors' aim was to explore associated factors with somatoform disorders. The authors studied 10 female patients with a diagnosis of somatization disorder or undifferentiated somatoform disorder with no comorbid current Diagnostic and Statistical Manual of Mental Disorders (4th edn) Axis I disorder and 12 healthy female volunteers. The predicting variables were temperament factors of the 240-item Temperament and Character Inventory instrument and regional brain glucose metabolism. Low novelty-seeking and high harm avoidance temperament traits and low caudate and low putamen glucose metabolism were statistically significantly associated with severe somatization (P < 0.05). In the present study, severe somatization associates with both altered brain glucose metabolism and temperament factors. No other studies on association of somatization with brain glucose metabolism and temperament have been published. The results are still considered exploratory due to the small number of subjects.

Adult↗
PubMed2005

The ST6GalNAc-I sialyltransferase localizes throughout the Golgi and is responsible for the synthesis of the tumor-associated sialyl-Tn O-glycan in human breast cancer.

The functional properties of glycoproteins are strongly influenced by their profile of glycosylation, and changes in this profile are seen in malignancy. In mucin-type O-linked glycosylation these changes can result in the production of mucins such as MUC1, carrying shorter sialylated O-glycans, and with different site occupancy. Of the tumor-associated sialylated O-glycans, the disaccharide, sialyl-Tn (sialic acid alpha2,6GalNAc), is expressed by 30% of breast carcinomas and is the most tumor-specific. The ST6GalNAc-I glycosyltransferase, which can catalyze the transfer of sialic acid to GalNAc, shows a highly restricted pattern of expression in normal adult tissues, being largely limited to the gastrointestinal tract and absent in mammary gland. In breast carcinomas, however, a complete correlation between the expression of RNA-encoding ST6GalNAc-I and the expression of sialyl-Tn is evident, demonstrating that the expression of sialyl-Tn results from switching on expression of hST6GalNAc-I. Endogenous or exogenous expression of hST6GalNAc-I (but not ST6GalNAc-II) always results in the expression of sialyl-Tn. This ability to override core 1/core 2 pathways of O- linked glycosylation is explained by the localization of ST6GalNAc-I, which is found throughout the Golgi stacks. The development of a Chinese hamster ovary (CHO) cell line expressing MUC1 and ST6GalNAc-I allowed the large scale production of MUC1 carrying 83% sialyl-Tn O-glycans. The presence of ST6GalNAc-I in the CHO cells reduced the number of O-glycosylation sites occupied in MUC1, from an average of 4.3 to 3.8 per tandem repeat. The availability of large quantities of this MUC1 glycoform will allow the evaluation of its efficacy as an immunogen for immunotherapy of MUC1/STn-expressing tumors.

Animals↗
PubMed2005

The worried young adult as a primary care patient.

BACKGROUND: Being worried about one's complaint is common among primary health care patients. Persistent and intensive worry may, however, have negative consequences. OBJECTIVES: We explored complaint-related worry and factors associated with it among 18- to 39-year-old primary health care patients. METHODS: Sixty-two patients evaluated the intensity of their worry and the severity of their complaint before seeing their GP. They were also interviewed about their background and filled in questionnaires about general tendency to illness-related worry and psychiatric symptoms. RESULTS: The intensity of worry varied greatly. One fourth of the patients reported intense worry. A general tendency to worry about health and hostile reactions were associated with both the intensity of worry and the severity appraisals. The patient's education and the duration and perceived course of the complaint also played a role in worrying and in the perceptions of the severity of the complaint. CONCLUSIONS: Some psychological characteristics may dispose patients to intensive worrying and pessimistic appraisals of their complaint. This challenges the GP to pay attention to the patients' perspectives and knowledge. Careful elucidation of the patients' experiences of their complaints is especially indicated in the case of complaints of long duration and a stable course.

Adolescent↗
PubMed2005

Novel binding epitope for Helicobacter pylori found in neolacto carbohydrate chains: structure and cross-binding properties.

Helicobacter pylori is a bacterium that colonizes the stomach of a majority of the global human population causing common gastric diseases like ulcers and cancer. It has an unusually complex pattern of binding to various host glycoconjugates including interaction with sialylated, sulfated, and fucosylated sequences. The present study describes an additional binding epitope comprising the neolacto internal sequence of GlcNAcbeta3-Galbeta4GlcNAcbeta. The binding was detected on TLC plates as an interaction with a seven-sugar ganglioside of rabbit thymus. The glycolipid was purified and characterized as Neu5Gcalpha3Galbeta4GlcNAcbeta3Galbeta4GlcNAcbeta3-Galbeta4Glcbeta1Cer with less than 10% of the fraction carrying a repeated lacto (type-1) core chain, Galbeta3Glc-NAcbeta3Galbeta3GlcNAcbeta. After stepwise chemical and enzymatic degradation and structural analysis of products the strongest binder was found to be the pentaglycosylceramide GlcNAcbeta3Galbeta4GlcNAcbeta3Galbeta4Glcbeta1-Cer, whereas the hexa- and tetraglycosylceramides were less active, and the trihexosylceramide was inactive. Further studies revealed that the terminal GlcNAcbeta of the pentaglycosylceramide may be exchanged for either GalNAcbeta3, GalNAcalpha3, or Galalpha3 without loss of the activity. Calculated minimum energy conformers of these four isoreceptors show a substantial topographical similarity suggesting that this binding is a result of a molecular mimicry. Although the glycoconjugate composition of human gastric epithelial cells is not known in detail it is proposed that repeating N-acetyllactosamine units of glycoconjugates may serve as bacterial attachment sites in the stomach.

Animals↗
PubMed2005

Analysis of proteins from a glioma cell line by using micro-scale solution isoelectric focusing in combination with liquid chromatography/tandem mass spectrometry.

In this study we have investigated whether micro-solution isoelectric focusing (microsol-IEF) can be used as a pre-fractionation step prior to liquid chromatography/tandem mass spectrometry (LC/MS/MS) and if extensive sample purification of the different fractions is required. We found that, in spite of the high concentrations of buffer and detergents, no clean up of the digested microsol-IEF fractions was necessary before analysis by LC/MS/MS. We also concluded that it is possible to identify at least twice as many proteins in a glioma cell lysate with the combination of microsol-IEF and LC/MS/MS than with LC/MS/MS alone. Furthermore, most of the proteins that were identified from one microsol-IEF fraction by using analytical narrow-range two-dimensional polyacrylamide gel electrophoresis (2D-PAGE) and peptide mass fingerprinting with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOFMS) were also identified by LC/MS/MS. Finally, we used the combination of microsol-IEF and LC/MS/MS to compare two sample preparation methods for glioma cells and found that several nuclear, mitochondria, and endoplasmic reticulum proteins were only present in the sample that had been subjected to lipid extraction by incubating the homogenized cells in chloroform/methanol/water.

Cell Line, Tumor↗
PubMed2005

Structure of needs among persons with schizophrenia.

BACKGROUND: The importance of needs assessment for service development has been widely recognised. Several studies have focused on the associations between ratings of needs by patients and staff and have found clear differences, especially concerning the unmet needs. METHODS: The present study is part of a Nordic Multicentre study that investigates the life and care of outpatients with a schizophrenia group illness in all the Nordic countries. The aim of this paper is to study the patterns of needs as identified by patients and staff according to the Camberwell Assessment of Needs (CAN). Quality of life, level of functioning, and psychiatric symptoms were assessed. RESULTS: The sample includes 300 patients, 194 (65%) men and 106 (35%) women. The factor analysis identified five factors for patients and four factors for staff in the questionnaire on ratings of needs. In four of the five patient-related factors a meaningful interpretation was possible, and the factors were named skills, illness, coping, and substance abuse. The staff-related factors were named skills, impairment, symptom, and substance abuse. There were significant associations between the sum scores constructed from the factors and measures of functioning level and symptoms. CONCLUSIONS: It seems that the sum factor reflecting secondary needs was the most important of the identified factors among both patient and staff ratings. The item-by-item comparisons in previous studies have emphasised differences between patient and staff ratings, but our analysis of the structure of needs also found similarities in the structures and in the associations between the identified sum scores and measures of symptoms, functioning level, and quality of life.

Adaptation, Psychological↗
PubMed2005

Regression analysis utilizing subjective evaluation of emotional experience in PET studies on emotions.

A methodological study on subject-specific regression analysis (SSRA) exploring the correlation between the neural response and the subjective evaluation of emotional experience in eleven healthy females is presented. The target emotions, i.e., amusement and sadness, were induced using validated film clips, regional cerebral blood flow (rCBF) was measured using positron emission tomography (PET), and the subjective intensity of the emotional experience during the PET scanning was measured using a category ratio (CR-10) scale. Reliability analysis of the rating data indicated that the subjects rated the intensity of their emotional experience fairly consistently on the CR-10 scale (Cronbach alphas 0.70-0.97). A two-phase random-effects analysis was performed to ensure the generalizability and inter-study comparability of the SSRA results. Random-effects SSRAs using Statistical non-Parametric Mapping 99 (SnPM99) showed that rCBF correlated with the self-rated intensity of the emotional experience mainly in the brain regions that were identified in the random-effects subtraction analyses using the same imaging data. Our results give preliminary evidence of a linear association between the neural responses related to amusement and sadness and the self-evaluated intensity of the emotional experience in several regions involved in the emotional response. SSRA utilizing subjective evaluation of emotional experience turned out a feasible and promising method of analysis. It allows versatile exploration of the neurobiology of emotions and the neural correlates of actual and individual emotional experience. Thus, SSRA might be able to catch the idiosyncratic aspects of the emotional response better than traditional subtraction analysis.

Adolescent↗
PubMed2005

Vulnerability to psychosis in patients attending primary and psychiatric care. Results of the RADEP study.

We studied occurrence of psychotic symptoms and their associations with occurrence of depressive and manic symptoms; 563 patients attending primary care (PrC) and 163 patients attending psychiatric outpatient care (PsC) completed a questionnaire including lists of psychotic, manic and depressive symptoms, and patients with depressive symptoms were interviewed using the same questionnaire 6 months after baseline examination. Of PrC patients, 8.5% and of PsC patients, 36.2% reported at least seven lifetime psychotic symptoms. During the 6-month follow-up, the corresponding figures were 0.22% for PrC and 2.84% for PsC patients. Among PrC patients, men, young, never-married, students and unemployed reported more psychotic symptoms than others. In multivariate analyses, occurrence of psychotic symptoms was associated with young age, never being married, poor functioning and former psychiatric treatment, as well as with occurrence of manic and depressive symptoms. Psychotic symptoms are rather prevalent in primary care and very common in psychiatric care. In primary care, vulnerability to psychosis is associated with the patient's background more strongly than in psychiatric care. Concurrent occurrence of psychotic symptoms with manic and depressive symptoms is common.

Adolescent↗
PubMed2004

Neuropsychological subtyping of schizophrenia.

Schizophrenia tends to be associated with a general decline in cognitive functioning. However, some studies have found neuropsychologically normal schizophrenia patients. To address this contradiction, we screened first-episode schizophrenic patients according to degree of neuropsychological dysfunction. At least three different neuropsychological subtypes of schizophrenia were found. Memory, specifically delayed recall, was the most important factor that discriminated the groups. Neuropsychological assessment, covering a range of functional domains of the major dimensions of behavior, has an important role in identifying preserved and impaired capacities, in predicting outcome, and in planning treatment.

Adolescent↗