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G Kolarz

Publications and source records attributed to G Kolarz.

At least 37 records · Page 2Linked to original sources

[New approaches to computer-assisted diagnosis of rheumatologic diseases].

UNLABELLED: Since the 1960s, several knowledge-based systems for computer-assisted diagnosis in radiology have been developed. The great majority of these tools has been implemented as off-line systems. This requires interaction with the system solely for the purpose of consultation and therefore interrupts the radiologist's work flow. This and inadequate man-machine interfaces may have inhibited the routine clinical use of such systems. The goal of this paper is to describe the current research toward the development of the on-line expert system Cadiag-4/Rheuma-Radio. The underlying fundamentals of the system design, including client/server architecture, communication interfaces, and fuzzy set theory and fuzzy logic as methods for knowledge representation and interference, are presented. METHODS: In radiology today, computers are routinely used to acquire radiological images in hospital and radiology information systems (HIS/RIS) and picture archiving and communication systems (PACS). In our approach, we make use of pre-existent sources of information to build an expert system that minimizes the interaction between radiologists and the computer. To handle uncertainty and vagueness of medical knowledge, fuzzy set theory and fuzzy logic are used. Given data of a specific case, a deductive inference procedure combines the observed radiological signs, establishes confirmed and excluded diagnoses as well as diagnostic hypotheses, and provides explanations for these conclusions. Furthermore, proposals for confirmation or exclusion of diagnostic hypotheses are offered. RESULTS: For evaluation purposes, an early prototype of Cadiag-4/Rheuma-Radio was tested on radiological disorders of the hip joint related to rheumatological diseases. Twenty radiological cases were used as test cases, reaching a diagnostic accuracy of about 80%. CONCLUSION: The first results are acceptable and encourage further work to cover the whole area of rheumatologically relevant radiological signs and diagnoses. Furthermore, research into the development of user-oriented data acquisition tools will be carried out.

Arthritis, Rheumatoid↗

Chest X-ray in collagen vascular diseases. A comparison of chest X-ray with bronchoalveolar lavage and transbronchial forceps biopsy.

The diagnostic value of chest X-ray following the ILO standards was compared with bronchoalveolar lavage (BAL) and the histology of transbronchial forceps biopsy in 83 patients with collagen vascular diseases. BAL in the middle lobe was considered abnormal in case of increased cell count per milliliter and/or lymphocytosis and/or neutrophil granulocytosis and this was found in 32 out of 42 cases (76.2%) with, and in 33 of out 41 cases (80.5%) without abnormal radiological finding. Pathological changes in the histology were found in 14 out of 20 cases (70.0%) with and in 40 out of 63 cases (63.5%) without abnormal chest X-ray in the upper lobe from which the transbronchial forceps biopsy specimens were obtained. In histological specimens obtained from transbronchial forceps biopsy, only fibrosis correlated with abnormal radiological findings in this region. Other inflammatory processes defied prediction by chest X-ray. This suggests that, regardless of chest X-ray findings, BAL should be performed together with transbronchial forceps biopsy for the histological examination of patients with collagen vascular diseases in which interstitial lung involvement is suspected.

Adolescent↗

[Binding capacity of ibuprofen to muscle proteins].

From former studies it is well known, that ibuprofen (CAS 15687-27-1) binds to muscular tissue in a higher degree than to tendons or ligaments. It is not known, however, what constituents of muscle tissue are responsible for this binding. Therefore the binding capacity of ibuprofen to different muscular proteins was studied. Actin, actomyosin, myosin, myoglobin, tropomyosin, lecithin, and native human collagen type I were incubated with 14C-ibuprofen and the specific binding was measured in relation to the total radioactivity. It could be shown that ibuprofen binds most markedly to actin. This binding could be inhibited by pre-incubation of ibuprofen with soluble actin. In comparison to the other proteins studied the specific binding of ibuprofen to actin was 4 to 5 times higher. As actin is a constituent of the cytoskeleton which plays an important role in generating oxygen radicals, its possible inhibition by ibuprofen could additionally explain the antiphlogistic effect of this compound.

Actins↗

Differences in anti-Fab antibodies in adult and late onset rheumatoid arthritis.

In the present study the ratio of antigen-bound anti-IgG-Fab antibodies (hidden aFab) to free aFab was found to be significantly increased in patients with adult onset rheumatoid arthritis (AORA) as compared to late onset rheumatoid arthritis (LORA). The overall amount of aFab was similar in both groups. The difference was only seen in seropositive patients. Within the seropositive AORA group, the aFab ratio was correlated with the duration and the stage of disease but not with the patients' age at investigation. This might reflect a higher affinity of anti-Fab antibodies and/or a greater diversity of the idiotypic repertoire in adult onset disease resulting in the formation of immune complexes, the stability of which might be enhanced further by the presence of rheumatoid factors. Although a pathophysiological involvement of aFab cannot be concluded from our observations, it is conceivable that different immunoregulatory mechanisms could be operative in RA with onset at different ages.

Adult↗

HLA-DR1-positive patients suffering from rheumatoid arthritis are at high risk for developing mucocutaneous side effects upon gold therapy.

Population studies suggest an association between RA and, depending on the ethnic background, HLA-DR1 and/or -DR4. One standard regimen for the treatment of RA is the use of gold compounds like SATM to arrest progression of the disease. In the present study, the immunogenetic background of RA patients developing side effects upon SATM treatment was determined. A total of 53 patients under SATM therapy were tested for their HLA-DRB and -DQ alleles by DNA typing; a significantly higher frequency of HLA-DR1 (p < 0.004, uncorrected) was observed in patients presenting with mucocutaneous side effects (MCT) when compared with patients without MCT. The RR was 6.85. Thus, HLA-DR1 seems to be a marker for the susceptibility of gold adverse reactions.

Adult↗

Bronchoalveolar lavage in rheumatoid arthritis.

Bronchoalveolar lavage (BAL) was performed on 70 RA patients, 28 without extra-articular manifestations, nine with pulmonary involvement, 13 with sicca-syndrome, 20 with other extra-articular manifestations such as renal involvement, cutaneous vasculitis and rheumatoid nodules. Fifteen patients without rheumatic or pulmonary disease served as the control group. Compared with the control group RA patients showed a statistically significant increase of lymphocytes, especially of activated (DR+)T(CD3+)-helper (CD4+) cells, resulting in a significantly diminished percentage of alveolar macrophages, B(CD21+)-lymphocytes, T-suppressor (CD8+) cells and an increased CD4/CD8 ratio. This cell distribution pattern was more pronounced in RA patients with lung involvement with significant differences to the other RA patients with regard to lymphocytes, DR positive cells and CD4 positive/DR positive cells. It is concluded that these results indicate an altered balance of immunocompetent cells not only in the joints but also in the lung. The changes are more distinct if local manifestations can be diagnosed clinically.

Aged↗

Lung involvement in rheumatoid factor-negative arthritis.

Bronchoalveolar lavage (BAL) was performed on 13 asymptomatic patients with sero (rheumatoid factor)-negative arthritis (SNA); (6 with peripheral psoriatic arthritis, 2 with axial psoriatic arthritis, 3 with ankylosing spondylitis, 2 with sacroiliitis). BAL revealed a significant decrease of neutrophil granulocytes and an increase of B-lymphocytes in patients with SNA in comparison with 64 patiénts with rheumatoid arthritis (RA; 24 seronegative, 39 seropositive) and 15 healthy controls. Patients with SNA and RA had a significant increase of lymphocytes, especially T, T-helper and activated cells. In addition patients with RA had a significant increase of natural killer cells and a lower percentage of alveolar macrophages and T-suppressor cells. Transbronchial biopsy was performed on 9 patients with SNA and on 59 patients with RA. Abnormal histologic features of lung tissue were observed in 4 out of 9 patients with SNA (2 with fibrosis, 1 with follicular lymphoid hyperplasia, 1 with desquamative interstitial pneumonitis). The abnormal lung histology in RA patients was more pronounced, however, the differences between SNA and RA were not significant. The data from BAL and histology suggest, that the pulmonary involvement in SNA and RA is caused by an unspecified immunologic process.

Adult↗

Bronchoalveolar lavage and lung biopsy in rheumatoid arthritis. In vivo effects of disease modifying antirheumatic drugs.

Bronchoalveolar lavage (BAL) and histology of transbronchial forceps biopsy was performed in 59 patients with rheumatoid arthritis (RA) to evaluate the in vivo effects of disease modifying drugs (DMARD). All patients had no clinical pulmonary symptoms and there was no evidence of drug induced alveolitis. Patients were divided into 5 subgroups according to drug treatment: 9 patients taking chloroquine, 15 patients gold, 8 patients penicillamine, 8 patients methotrexate (MTX) and 19 patients not taking DMARD. Duration of DMARD regimen was more than 3 months. No patient was treated with corticosteroids. BAL results revealed an increased percentage of lymphocytes and a diminished proportion of alveolar macrophages in patients treated with gold, penicillamine, MTX and no DMARD. In contrast, patients receiving chloroquine had a normal distribution of lymphocytes and macrophages as seen in a control group of 15 persons. Patients taking MTX showed a normal distribution of T and B lymphocytes and DR positive cells, whereas patients receiving chloroquine, gold, or penicillamine had an elevated proportion of T lymphocytes and DR positive cells and a diminished percentage of B lymphocytes. The latter was also observed in patients not taking DMARD. The percentage of natural killer cells was significantly elevated only in the penicillamine group. Patients receiving gold had higher absolute values of CD3, CD4 and DR positive cells. Abnormal lung histology was associated with an increased percentage of lymphocytes and with higher DR positive cells in BAL. Patients not receiving DMARD had a significantly higher percentage (42.1%) of abnormal histologic features of lung tissue than patients receiving DMARD (17.5%).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗

Prediction of interstitial lung involvement in rheumatoid arthritis. The value of clinical data, chest roentgenogram, lung function, and serologic parameters.

We initiated the present study to predict interstitial lung involvement in rheumatoid arthritis (RA) by means of logistic regression analysis of clinical data, lung function, chest roentgenogram, and serologic parameters. Fifty-eight nonsmoking patients with RA were randomized from the rheumatologic unit and sent for investigation to the pulmonary department. Bronchoalveolar lavage (BAL) was performed in the middle lobe and the BAL fluid was considered abnormal in case of increased cell count per milliliter and/or lymphocytosis and/or neutrophil granulocytosis; these findings or combinations thereof were found in 42 (72.4 percent) of 58 cases. The patients' data that had an impact on the normality of BAL were the sex (p = 0.001), vital capacity (p = 0.028), peripheral blood T-helper cells (OKT4+) (p = 0.025), DR(+)-lymphocytes (p = 0.002), and antinuclear antibodies (p = 0.025). By means of the logistic regression analysis, it was possible to reach high significance in the prediction of interstitial lung involvement, with a sensitivity of 92.9 percent and a specificity of 75.0 percent (p less than 10(-6)). The efficiency of prediction was 87.9 percent. From these results, we conclude that interstitial lung involvement in RA is predictable from laboratory findings that have been yielded by noninvasive diagnostic techniques. These data should be used in clinical routine monitoring and they may help to facilitate the assessment of whether bronchoscopy is indicated.

Arthritis, Rheumatoid↗

[Binding affinity of ibuprofen in human tissues].

In vitro binding of ibuprofen (CAS 15687-27-1) to various human tissues was studied to explain differences in tissue concentration after local application of ibuprofen cream. Radioactive ibuprofen, was incubated with human skin, subcutaneous tissue, muscle, tendon, joint capsule for 2 h at 37 degrees C. Tissue specimens were washed and radioactivity was measured by a liquid scintillation counter. The results show specific binding of ibuprofen to the various tissues of different degrees. Despite of interindividual differences muscle tissues showed the highest, tendons the lowest concentrations of ibuprofen. These findings may explain the in vivo results, where higher concentrations of ibuprofen were found in muscle tissue compared with subcutaneous tissue.

Aged↗

A method to differentiate between anti-C1q antibodies and C1q-binding immune complexes using collagenase-digested solid phase C1q.

A method for the detection of circulating immune complexes in the presence of autoantibodies to C1q is described. Solid phase C1q-digestion with bacterial collagenase results in the elimination of the collagen-like region of C1q. Binding of model immune complexes to this modified solid phase C1q is practically unaltered, while reactivity of anti-C1q antibodies is abolished by this procedure. In conjunction with an ELISA using the collagen-like region of C1q as antigen this modified C1q solid phase assay may be used to determine immune complexes and anti-C1q antibodies in the sera of patients with autoimmune rheumatic diseases.

Antibodies, Monoclonal↗

[Rehabilitation after lumbar intervertebral disk operation].

122 patients were admitted 3 months after a lumbar disc operation to a rehabilitation clinic. Conservative treatment during the rehabilitation induced a decrease of low back pain (70 out of 107 patients), of paresis (30/51 patients), and of paresthesia (51/77 patients). More than 20 pre- and post-operative variables were tested with a rank-variance analysis regarding a possible influence on efficacy of the rehabilitation treatment. The success of the conservative treatment measured by improvement of paresis, paresthesia, pain and mobility of lumbar spine was influenced favourably by preoperative paresis (p less than 0.03). Women showed more often than men an improvement of paresis (p = 0.006) immediately after surgery. Patients with a preoperative paresis had a shorter history of radicular symptoms (p = 0.002), an acute onset was seen more often in patients with persistent paresis (p = 0.019). Paresthesia was found more frequently before surgery (p = 0.010) and at begin of rehabilitation (p = 0.006) in patients with paresis compared to patients without paresis. A statistically significant association was also evaluated between decreased lumbar mobility and laminectomy (p = 0.007). Patients with L5/S1 disc operation had a longer duration of radicular symptoms (p = 0.012), a decreased frequency of paresis (p = 0.040), but more often paresthesia (p = 0.001) compared with L4/5 operation.

Adult↗

[Helicobacter pylori and nonsteroidal antirheumatics].

The frequency of occurrence of Helicobacter pylori in the antral mucosa was investigated prospectively in a group of 66 patients (17 men, 49 women, mean age 58 +/- 8.4 years) who had been treated with nonsteroidal anti-rheumatic drugs and 33 controls (14 men, 19 women, mean age 60.7 +/- 6.6 years) who had not received these drugs. In the first group the indication for gastroscopy was ingestion of nonsteroidal antirheumatic drugs for at least 8 weeks, irrespective of dyspeptic symptoms (present in 25 patients), while in the second group the reason for endoscopy was either clinical symptoms (n = 18) or the presence of blood in the faeces. Helicobacter pylori was demonstrated by culture in 36 out of the 66 patients who had received nonsteroidal antirheumatics (54.5%); these comprised 24 out of 46 patients (52.2%) with chronic inactive gastritis and 12 out of 15 patients (80%) with chronic active gastritis. In the control group H. pylori was detected by culture in 22 out of 33 patients (66.7%); these included 11 out of 19 patients (57.9%) with chronic inactive gastritis and 11 out of 12 patients (91.7%) with chronic active gastritis. H. pylori was not demonstrated in any of the seven patients who had histologically normal gastric mucosa. In both groups there was significant correlation between demonstration of the microorganism and severity of inflammation. There is hence no evidence that nonsteroidal antirheumatic drugs have any influence on the colonisation of the antral mucosa by Helicobacter pylori.

Anti-Inflammatory Agents, Non-Steroidal↗

Bronchoalveolar lavage in rheumatoid arthritis and secondary Sjögren's syndrome.

Bronchoalveolar lavage (BAL) was performed to investigate pulmonary involvement in 39 patients with rheumatoid arthritis (RA) and in 7 patients with RA and secondary Sjögren's syndrome, and compared to 12 healthy controls. Lymphocytosis (more than 15%) was seen in 25, and more than 3% neutrophil granulocytes in 8 of 39 patients with RA. Lymphocytosis and/or neutrophil granulocytosis was seen in both seropositive and seronegative patients irrespective of clinical or radiologic findings. Patients with RA with or without secondary Sjögren's syndrome had increased DR+ lymphocytes in BAL compared with peripheral blood. In 7 patients with secondary Sjögren's syndrome an increased helper/suppressor cell index (OKT4+/OKT8+: 7.65 +/- 2.10) and increased natural killer cells (OKNK+: 27.3 +/- 5.5%) were found, as compared to 39 other patients with RA (OKT4+/OKT8+: 2.16 +/- 0.33, p less than 0.05; OKNK+: 14.5 +/- 2.3%, p less than 0.05). These BAL data are further evidence of frequent subclinical interstitial pulmonary involvement in RA with differences in the active autoimmune process from those in secondary Sjögren's syndrome.

Aged↗