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A Eklund

Publications and source records attributed to A Eklund.

At least 55 records · Page 3Linked to original sources
PubMed2001

Analysis of intracellular cytokines in CD4+ and CD8+ lung and blood T cells in sarcoidosis.

In pulmonary sarcoidosis, activated T cells accumulate in the lungs. We hypothesized that the balance between the T-helper type 1 (Th1) cytokines (interferon [IFN]-gamma and interleukin [IL]-2) and Th2 cytokines such as IL-4, IL-5, and IL-10 might explain differences in clinical outcome in pulmonary sarcoidosis, such as why patients of human leukocyte antigen (HLA) type DR17 have a much better prognosis than those of other HLA types. Peripheral blood lymphocytes (PBL) and lymphocytes obtained by bronchoalveolar lavage (BAL) from HLA-typed sarcoidosis patients, as well as PBL from healthy controls, were stimulated in vitro, fixed, and permeabilized with saponin. Thereafter, cells were stained with fluorescence- labeled antibodies specific for intracellular cytokines (IL-2, IL-4, IFN-gamma, and tumor necrosis factor (TNF)-alpha and cell surface markers CD4 and CD8, and were subjected to flow-cytometric analysis. In bronchoalveolar lavage fluid (BALF), there were significantly greater frequencies of T cells positive for IFN-gamma and TNF-alpha than there were among PBL, and significantly fewer cells positive for IL-4, in both the CD4+ and CD8+ subsets. HLA-DR17-positive patients showed a tendency toward a less pronounced Th1 response that may be related to their good prognosis. Sarcoidosis patients had higher frequencies of cells positive for IFN-gamma, IL-4, and IL-2 in their blood than did healthy controls, a finding that may reflect the systemic nature of sarcoidosis. A clear Th1 cytokine profile of CD4+ as well as of CD8+ T cells was demonstrated in BALF from sarcoidosis patients. This was most pronounced for CD8+ cells, which may therefore make an important contribution to the inflammatory process in the lungs in pulmonary sarcoidosis.

Adult↗
PubMed2001

Highly activated T-cell receptor AV2S3(+) CD4(+) lung T-cell expansions in pulmonary sarcoidosis.

Sarcoidosis is a systemic disorder of unknown origin, primarily affecting the lungs. The granulomatous inflammation is driven by the interplay between various molecules and cells, including T cells. Previously, our group reported a close correlation between lung-restricted T-cell receptor (TCR) AV2S3 CD4-positive T-cell expansions and HLA-DR17 in active sarcoidosis. The aim of this study was to characterize phenotypically such AV2S3 lung T cells, to obtain more information about the state of activation of this intriguing T-cell subset. Bronchoalveolar lavage (BAL) was performed on sarcoidosis patients with active disease and on healthy control subjects (HC). The expression of activation and subset markers was evaluated and compared between BAL AV2S3-positive and AV2S3-negative T cells of patients with lung-restricted AV2S3 T-cell expansions, and between BAL and peripheral blood lymphocytes (PBL) of patients and HC. The frequency of cells expressing activation markers CD26, CD28, CD69, and HLA-DR was enhanced in AV2S3-positive versus AV2S3-negative BAL CD4(+) T-cell subsets. In contrast, CD25 (Il-2R) and CD27 were expressed at lower levels by the AV2S3-positive CD4(+) lung T cells. Our data confirm a substantial activation of BAL CD4(+) T cells of patients with sarcoidosis. Furthermore, the AV2S3 CD4-positive lung cells display a pattern of activation markers, suggesting that they are significantly more activated compared with lung CD4(+) T cells expressing other TCR V gene segments as well as compared with BAL CD4(+) T cells of HC. These results support our hypothesis of an ongoing and selective stimulation of AV2S3 T cells by a specific antigen and the participation of this subset in the inflammatory process in the lungs of patients with sarcoidosis.

Adult↗
PubMed2001

Human leukocyte antigen genes may outweigh racial background when generating a specific immune response in sarcoidosis.

Presented is a sarcoidosis patient of African origin, who was adopted at an early age and grew up in Sweden. This patient displayed an immune response identical to that previously reported in human leukocyte antigen (HLA)-DR17 positive Caucasian sarcoidosis patients in Scandinavia, with T-cell receptor AV2S3+ T-cells accumulating in the lungs. HLA typing also established that she was DR17 positive, which is a rare HLA type for individuals of African origin. To the authors' knowledge, this specific immune response has not previously been reported in patients of African origin. Moreover, the clinical manifestations of sarcoidosis were similar to those known to be strongly linked to HLA-DR17 in Scandinavians, i.e. with Löfgren's syndrome. The case presented here suggests certain human leukocyte antigen genes to be strongly linked to specific immune responses that are identical irrespective of the racial background. If such an immune response were important for the subsequent clinical manifestations, this case would argue for the importance of human leukocyte antigen genes in the genetic predisposition to sarcoidosis.

Adoption↗
PubMed2001

Two computerized methods used to analyze intracranial pressure B waves: comparison with traditional visual interpretation.

OBJECT: Slow and rhythmic oscillations in intracranial pressure (ICP), also known as B waves, have been claimed to be one of the best preoperative predictive factors in idiopathic adult hydrocephalus syndrome (IAHS). Definitions of B waves vary widely, and previously reported results must be treated with caution. The aims of the present study were to develop a definition of B waves, to develop a method to estimate the B-wave content in an ICP recording by using computer algorithms, and to validate these procedures by comparison with the traditional visual interpretation. METHODS: In eight patients with IAHS, ICP was continuously monitored for approximately 20 hours. The ICP B-wave activity as a percentage of total monitoring time (B%) was estimated by using visual estimation according to the definition given by Lundberg, and also by using two computer algorithms (Methods I and II). In Method I each individual wave was classified as a B wave or not, whereas Method II was used to estimate the B-wave content by evaluating the B-wave power in 10-minute blocks of ICP recordings. CONCLUSIONS: The two computerized algorithms produced similar results. However, with the amplitude set to 1 mm Hg, Method I yielded the highest correlation with the visual analysis (r = 0.74). At least 5 hours of monitoring time was needed for an acceptable approximation of the B% in an overnight ICP recording. The advantages of using modern technology in the analysis of B-wave content of ICP are obvious and these methods should be used in future studies.

Aged↗
PubMed2001

Cerebrospinal fluid hydrodynamics after placement of a shunt with an antisiphon device: a long-term study.

OBJECT: Few studies have been performed to investigate the cerebrospinal fluid (CSF) hydrodynamic profile in patients with idiopathic adult hydrocephalus syndrome (IAHS) before and after shunt implantation. The authors compared the in vivo CSF hydrodynamic properties, including the degree of gravity-induced CSF flow, of a shunt with an antisiphon device with a standard shunt. METHODS: Twelve patients with IAHS underwent insertion of shunts with Delta valves. Clinical testing, magnetic resonance imaging, and CSF hydrodynamic investigations were conducted with intracranial pressure (ICP), gravity effect, and pressure-flow curve of the shunt estimated at baseline and at 3 and 12 months postoperatively. No shunt was revised. Despite postoperative clinical improvement in all patients who received Delta valves, the mean ICP was only moderately reduced (mean decrease at 3 months 0.3 kPa [p = 0.02], at 12 months 0.2 kPa [not significant]). Patients with the greatest increase in ICP preoperatively had the most pronounced decrease postoperatively. The hydrostatic effect of the Delta valves was significantly lower than with the Hakim shunts (0.1-0.2 kPa compared with 0.6 kPa). The increased conductance (that is, lowered resistance) was up to 14 times higher with the Delta valves compared with preoperative levels. CONCLUSIONS: The function of a CSF shunt may be more complicated than previously thought; the subcutaneous pressure acting on the antisiphon device can modify the shunt characteristics. A compensatory increase in CSF production may counteract the increased outflow through the shunt. The improved CSF outflow conductance may increase the intracranial compliance and thereby dampen a pathological ICP waveform.

Aged↗
PubMed2001

Inflammatory BAL-fluid and serum parameters in HLA DR17 positive vs. DR17 negative patients with pulmonary sarcoidosis.

BACKGROUND AND AIM OF THE WORK: We have previously shown that HLA DR17 is associated with a favourable prognosis in Scandinavian sarcoidosis patients. By studying inflammatory parameters in these patients we wished to increase the knowledge of the involved mechanisms that may underlie good prognosis. METHODS: BAL was performed in 118 sarcoidosis patients, 67 HLA DR17 positive and 51 DR17 negative. BAL cell profile was analysed. The CD4 and CD8 lymphocyte phenotype was determined by flow cytometry. BALF-albumin, BALF-fibronectin (FN) and BALF-procollagen III aminoterminal peptide (PIIINP) were analysed by nephelometric, ELISA and RIA methods respectively. Neopterin and soluble interleukin-2 receptor (sIL2R) in serum were also determined by ELISA. Angiotensin-converting enzyme (ACE) in serum was analysed by spectrophotometry. RESULTS: In DR17+ patients, BAL lymphocytes and eosinophils were significantly decreased (median 30.2 and 0.19 x10(6)/L) compared to DR17- (median 50.2 and 0.64 x 10(6)/L respectively). However the BAL CD4/CD8 ratio was increased in the DR17+ group compared to DR17- (6.2 vs. 4.3). BALF-albumin, FN and PIIINP did not differ between the groups. Serum parameters were decreased in DR17+ patients compared to DR17- (ACE median 28.7 vs. 35.1 U/L, neopterin 9.1 vs. 12.7 nmol/L and sIL2R 296 vs. 605 U/L). CONCLUSIONS: The study revealed that an increased BAL CD4/CD8 ratio, in contrast to BAL lymphocytosis, was seen in a subgroup of sarcoidosis patients earlier associated with a favourable prognosis. Our results support that an increased BAL CD4/CD8 ratio is a favourable parameter in sarcoidosis. The lower ACE activity in the DR 17+ group indicates a reduced granuloma burden in this patient subgroup.

Adult↗
PubMed2001

ECG-abnormalities in Japanese and Swedish patients with sarcoidosis. A comparison.

BACKGROUND AND AIM OF THE WORK: ECG abnormalities are more common in patients with sarcoidosis than in controls. The incidence of cardiac sarcoid granulomas in the Japanese population has been found to be higher than that seen in Caucasians. We compared the prevalence of ECG abnormalities in Japanese and Swedish patients with sarcoidosis. METHODS: Twelve-lead routine ECG's were compared between consecutive patients (134 Japanese and 149 Swedish) of similar age with histologically verified sarcoidosis or a high clinical probability of the disease and a history of no more than 12 months before the ECG. RESULTS: There was no statistically significant difference in the prevalence of first degree AV block, ST-T-segment abnormalities, right bundle branch block (RBBB) and left anterior block (LAH) in Japanese and Swedish patients. Among the Swedes, the results were compared with those of a smaller group (n = 29) of older patients with a longer disease course. In these few patients LAH and RBBB occurred more frequently than in patients with a recent diagnosis. CONCLUSIONS: ECG abnormalities in patients with sarcoidosis seem to be of similar frequency in Japan and Sweden. ST-T changes and first degree AV block would appear early in the course of the disease, whereas more pronounced conduction defects may appear later.

Cardiomyopathies↗
PubMed2000

[It's difficult to differentiate between sarcoidosis and berylliosis!].

Chronic beryllium disease (CBD), caused by exposure for beryllium (Be), is an inflammatory disease very similar to sarcoidosis. Materials containing Be are encountered in aerospace, nuclear weapons, electronic and computer industries. Two cases of probable CBD, initially diagnosed as sarcoidosis, are described. Both patients have a history of possible exposure to Be. CBD can be detected and diagnosed by using the Be proliferation test.

Adult↗
PubMed2000

An immobiline DryStrip application method enabling high-capacity two-dimensional gel electrophoresis.

In the field of proteomics the need to detect low-abundance cellular components, such as regulatory proteins, is of critical importance. Two-dimensional polyacrylamide gel electrophoresis (2-D PAGE) is one of the most commonly used separation tools for these biological investigations. In this paper we report an alternative micropreparative 2-D PAGE sample application method, called the "paper bridge loading" method. This method makes it possible to apply a larger sample volume to commercially available immobilized pH gradient (IPG) strips. The Vh products required for focusing are only marginally longer than those used in analytical experiments. The method was compared to traditional cup loading and in-gel rehydration. With 18 cm long narrow-range Immobiline DryStrip pH 4.5-5.5, the "paper bridge" method allowed the application of 10 mg human plasma proteins compared to 3 mg with traditional loading methods. The corresponding figures using Escherichia coli sample was found to be 6 mg and less than 2 mg, respectively. The paper bridge method also showed the best results in terms of spot resolution and separation of high molecular weight proteins.

Acrylamides↗
PubMed2000

Decreased pulmonary levels of the anti-inflammatory Clara cell 16 kDa protein after induction of airway inflammation in asthmatics.

The Clara cell 16 kDa protein (CC16) maps to an atopy-associated region of chromosome 11 and has been ascribed an anti-inflammatory function. Using reverse-phase HPLC and Western blot analysis, we have evaluated the polypeptide pattern in bronchoalveolar lavage (BAL) fluid retrieved from asthmatics, before and after induction of airway inflammation by low-dose allergen inhalation challenge. A prominent decrease of CC16 was seen after induction of inflammation, and a further CC16 decrease was observed in lavage fluid where surfactant had been removed. Reduced levels of pulmonary CC16 may cause loss of anti-inflammatory activity in the airways and contribute to the development of airway inflammation in asthma.

Albumins↗
PubMed2000

Increased interleukin-13 mRNA expression in bronchoalveolar lavage cells of atopic patients with mild asthma after repeated low-dose allergen provocations.

Immune and inflammatory responses mediated by cytokines are essential in the pathophysiology of asthma. The aim of this study was to analyse the cytokine mRNA profiles in bronchoalveolar lavage (BAL) cells of patients with mild atopic asthma, before and after induction of a subclinical allergic airway inflammation. For this purpose, eight patients with mild atopic asthma received low-dose allergen inhalations equivalent to 10% of a provocational dose causing a 20% fall in forced expiratory flow in 1 sec (PD20) for 7 weekdays. BAL was performed before and after low-dose provocations in patients, and without provocation in five healthy controls. Alveolar macrophages (AM) were enriched by negative selection, using magnetic beads, to enable separate studies of the BAL cells. Using a semiquantitative RT-PCR technique, the mRNA expression of macrophage-derived cytokines interleukin (IL)-1, IL-6, IL-8, IL-10, IL-12, IL-13, interferon (IFN)-gamma, tumour necrosis factor (TNF)-alpha and transforming growth factor (TGF)-beta was analysed. After low-dose provocations, we observed a significant increase in the expression of IL-13 mRNA (P = 0.01) in BAL cells enriched for AM of the asthmatic patients. The increased IL-13 mRNA positively correlated with the proportion of BAL fluid eosinophils (r = 0.7, P = 0.05). Moreover, a tendency was found towards an increased IL-1 and a reduced IL-6, IL-8, IFN-gamma and TNF-alpha expression by the BAL cells. Comparing asthmatic patients before low-dose provocations and healthy controls, a significantly higher expression of IL-6 (P<0.003), IL-10 (P<0.005) and TGF-beta (P<0.003) and a significantly lower expression of IL-8 (P<0.005) and TNF-alpha (P<0.01) was detected in the patients. In summary, repeated low-dose allergen provocations of asthmatic patients results in a modified BAL cell cytokine mRNA profile with increased production of IL-13, that may be of importance for the development of a Th2-like immune response. A possible source of the increased IL-13 mRNA is AM, which may have a more active function in the allergic inflammation than previously thought.

Adult↗
PubMed2000

Misleading results of ethanol analysis in urine specimens from rape victims suffering from diabetes.

We report appreciably high concentrations of ethanol (82 and 102 mg/dL) in specimens of urine collected from two victims of date rape. Both girls (aged 15 and 18 years) suffered from diabetes mellitus, but adamantly denied drinking any alcohol before or after the incident. The presence of glycosuria and high risk of fungal infections in female diabetics suggests that ethanol was produced in vitro by fermentation after voiding. Making a routine test for sugar in the urine and ensuring that the sampling tubes contain sufficient sodium or potassium fluoride to inhibit glycolysis are recommended practices. A specific marker for post-sampling synthesis of ethanol might also be used such as the 5HTOL/5HIAA ratio.

Journal Article↗
PubMed2000

A resonator sensor for measurement of intraocular pressure--evaluation in an in vitro pig-eye model.

Intraocular pressure (IOP) measurement is performed routinely at every eye clinic. High IOP, which can be a sign of glaucoma, can lead to degeneration of the retina and can cause blindness. In this study we developed a resonator sensor for IOP measurement based on an oscillator consisting of a piezoelectric element made of lead zirconate titanate, a flat contact piece of nylon and a feedback circuit. The aim of this study was to evaluate the new sensor's ability to determine lOP in an in vitro pig-eye model. Six eyes from four pigs were removed and fixed in agar. They were then pressurized by a saline column (10-35 cm H2O) through a cannula inserted into the vitreous chamber. The IOP was measured with the resonator sensor applied to cornea. An Alcon applanation pneumatonometer and a standard Viggo-Spectramed pressure sensor connected to the saline column were used as references. The IOP as measured with the resonator sensor correlated well with the pressure elicited by the saline column for individual eyes (r = 0.96-0.99, n = 60) and for all eyes (r = 0.92, n = 360). The correlation between the resonance sensor and the pneumatonometer was r = 0.92 (n = 360). The pneumatonometer also showed a good correlation with the saline column (r = 0.98, n = 360). We conclude that our in vitro pig-eye model made it possible to induce reproducible variation in IOP, and measurement of that pressure with the newly developed resonator sensor gave very promising results for development of a clinically applicable IOP tonometer with unique properties.

Acoustics↗
PubMed2000

Lung T-helper cells expressing T-cell receptor AV2S3 associate with clinical features of pulmonary sarcoidosis.

In previous reports of studies of Scandinavian sarcoidosis patients, we have described a strong association between lung-restricted expansions of T cells expressing T-cell receptor (TCR) AV2S3 and the human leukocyte antigen (HLA)-DRB1*0301 (DR17) and -DRB3*0101 alleles, suggesting the presence of a specific antigen in sarcoidosis. In the present study, the degree of lung-accumulated TCR AV2S3(+) T cells was related to clinical data in 51 HLA-DRB1*0301/DRB3*0101-positive Scandinavian patients with pulmonary sarcoidosis. Significantly more AV2S3(+) lung T cells (median: 30.0% of CD4(+) cells in bronchoalveolar lavage fluid [BALF]) were found accumulated in patients with a short (< 2 yr) than with a long (> 2 yr) (median: 18.6%) disease duration (p = 0.003). A strong positive association was also found between lung-restricted AV2S3(+) T cells and both the CD4(+)-to-CD8(+) cell ratio (p = 7 x 10(-6)) in BALF and with an acute disease onset (p = 0.018). Negative associations were found between both the interval from disease onset to bronchoalveolar lavage (p = 0.0001) and the age of the patient (p = 0.002). Our findings strongly link lung-accumulated AV2S3(+) T cells to the acute inflammatory response in sarcoidosis. Moreover, the association of these cells with a good prognosis indicates that AV2S3(+) T cells may have a protective role against a presumed sarcoidosis antigen.

Adult↗
PubMed2000

Rat alveolar and interstitial macrophages in the fibrosing stage following quartz exposure.

Exposure to quartz induces pulmonary inflammation and development of fibrosis. In order to study the fibrosing process, we investigated morphology, function and phenotype of alveolar (AMs) and interstitial (IMs) macrophages at an early stage of fibrosis in rats. Rats were exposed by intratracheal instillations of 10 mg quartz (n=8) or saline (n=8) and studied 3 months later. AMs were obtained by bronchoalveolar lavage and IMs by mechanical fragmentation, followed by enzymatic digestion of lung tissue. Histology revealed subacute silicosis, with early focal fibrosis and alveolar lipoproteinosis. AM quartz exposure increased phagocytic activity and expression of major histocompatibility complex (MHC) Ia antigens, the latter being associated with cellular antigen presenting capacity. IM had an even more pronounced expression of MHC than AM after quartz exposure. Both macrophage fractions had a higher expression of OX-42 (complement receptor 3, CR3) than controls, but the increase in the IM fraction might be explained by the remaining AM in the IM fraction. Exposed AM adhered less to extracellular matrix components (vitronectin and fibronectin) than controls. In contrast, the adhesion of IM to vitronectin increased after exposure. Besides increased adhesion, the effects on IM were scarce. Our results therefore do not support the hypothesis that IM has a key role in the process of inflammation, including fibrosis.

Animals↗
PubMed2000

Clara cell secretory protein. Levels in BAL fluid after smoking cessation.

STUDY OBJECTIVES: The bronchiolar Clara cell is a major target for tobacco smoke exposure. To improve our understanding of the putative regenerative/repair mechanism(s) in the bronchiolar epithelium, we measured the levels of the Clara cell secretory protein (CCSP) in BAL fluid in healthy volunteers following smoking cessation. DESIGN: BAL was performed before smoking cessation, and at 1, 3, 6, 9, and 15 months following smoking cessation, in eight healthy volunteers with a previous mean cigarette consumption of 19 pack-years. The levels of CCSP in BAL fluid were assessed in immunoblotting experiments using an antibody against human CCSP. RESULTS: Significantly (p < 0.05) higher levels of CCSP in BAL fluid were observed at 3, 6, and 9 months after smoking cessation, while the levels of CCSP in BAL fluid at 15 months after smoking cessation were the same as those before smoking cessation. CONCLUSIONS: Despite the long history of smoking among patients in the present study group, signs of early regeneration in the bronchiolar epithelium were noted, in that the levels of CCSP in BAL fluid were elevated at the indicated time points following smoking cessation. Furthermore, we propose that the insult to the bronchiolar epithelium made by cigarette smoking caused the levels of CCSP in the BAL fluid at 15 months after smoking cessation to return to the levels noted before smoking cessation. The present study suggests a role for CCSP as a marker for nonciliated bronchiolar cell function.

Adult↗
PubMed2000

Altered expression of natural killer cell inhibitory receptors (KIRs) on T cells in bronchoalveolar lavage fluid and peripheral blood of sarcoidosis patients.

BACKGROUND AND AIM OF THE WORK: The role for natural killer cell inhibitory receptors (KIRs) on T cells is not fully understood, but signalling through KIRs on T cells may inhibit T cell receptor mediated activation, and KIR expression has been suggested to be one mechanism of controlling T cell mediated immune responses. An aberrant KIR expression on T cells could thus be of importance in autoimmune as well as infectious disorders. Sarcoidosis patients have several immunological impairments that have not been clarified, and we here examined the KIR expression on CD4+ and CD8+ peripheral blood (PBL) and bronchoalveolar lavage (BAL) T cells of sarcoidosis patients and controls. METHODS: We used three KIR specific monoclonal antibodies, namely DX9 (specific for p70), DX27 (p58) and DX22 (specific for CD94, that belongs to another major group of KIRs) and flow cytometry. RESULTS: p70 was expressed lower in patient CD8+ PBL (median 2.3%) compared to controls (6.3%) (p < 0.01). In patients, p58 was expressed by less CD8+ BAL lymphocytes (median 1.2%) compared to PBL (6.8%) (p < 0.01) while CD94 was expressed by more CD8+ BAL lymphocytes (median 14.5%) compared to PBL (9.6%) (p < 0.01). Moreover, in CD8+ PBL, CD94 and p58 were expressed significantly lower in patients with an active vs. inactive disease, and in patients with chest radiographic stage I vs. stage II, respectively. CONCLUSIONS: The significantly altered expression of distinct KIRs on CD8+ T cells in sarcoidosis, especially in patients with signs of an active disease, indicate these cells to be dysregulated and implicate them in the pathogenesis of the disease.

Adult↗