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Biomedical subjects

M Fischer

Publications and source records attributed to M Fischer.

At least 469 records · Page 26Linked to original sources
PubMed1992

[Coronary artery bypass with 2 internal mammary arteries. Early clinical and angiographic results in 100 patients].

One hundred patients underwent coronary revascularisation with both internal mammary arteries between 1987 and 1990. The average age of the patients was 55 years. The left internal mammary was used in 97 of the 100 cases as a pediculated graft to revascularise the left anterior descending (66 cases), left lateral (27 cases) or a bissecting artery (4 cases). The right internal mammary was used as a pediculated graft in 51 cases and as a free graft to revascularise a left lateral (51 cases), left anterior descending (29 cases) or right coronary artery (20 cases). There was one death in the first 30 postoperative days. Morbidity was low with no cases of sternal infection. The average postoperative bleeding was 633 +/- 550 ml per patient. The incidence of phrenic nerve paralysis decreased from 36% in the first 50 patients to 6% in the second 50 patients. Angiography at the 10th postoperative day showed 4 occlusions out of 132 internal mammary arteries opacified (97% patency). Ninety four patients are asymptomatic and have negative exercise stress tests. Mortality and morbidity of coronary surgery using the two internal mammary arteries are therefore the same as those of conventional coronary surgery using saphenous veinar only one internal mammary artery, providing that it is reserved for patients in good general condition, under 65 years of age, without obesity or diabetes. This technique of coronary artery revascularization should provide better long-term results because of the high patency rate of the grafts.

Adult↗
PubMed1992

[4-years experience with quality control of decentralized reflectometry blood glucose measurement in the Vienna-Lainz hospital].

Since 1987 a quality control programme for ward-based blood glucose assays has been established in Lainz Hospital, Vienna. In 1991 following a decision to standardise the type of reflectometer used in the ward, 62 Reflolux IIS reflectance meters (Boehringer Mannheim) were assessed in a quality control consisting of 4 ring trials a year (blood glucose determination in two "unknown" samples) and in daily measurements of control solutions of known glucose concentrations. Experience with this quality control procedure is reported in this presentation of the relevant results of the ring trials. The most frequent errors in performing the test are discussed and the importance of instructing and training the nursing staff in the proper use and maintenance of the meters is pointed out.

Austria↗
PubMed1991

Influence of severity of heart failure on the efficacy of angiotensin-converting enzyme inhibition.

Angiotensin-converting enzyme (ACE) inhibition slowed the progression of congestive heart failure (CHF) in 170 patients who were randomly assigned to either captopril or placebo in the Munich Mild Heart Failure Trial. The two major end points were progression from New York Heart Association (NYHA) functional classes I, II, or III to class IV, despite optimal, adjusted standard therapy, and death due to CHF. The relative risk for progressive CHF with captopril therapy was 0.34 (95% confidence interval = 0.17-0.68; p = 0.01). A total of 52 prerandomization variables were tested to determine their contribution to disease progression. Logistic regression analysis revealed 5 independent risk factors for progressive CHF: NYHA class, left ventricular end-systolic diameter, need for diuretic, age, and cardiothoracic ratio. The presence of greater than 2 of these risk factors increased the odds ratio for progression to 8.13 (p less than 0.001) compared with the presence of 0-2 risk factors. However, the effectiveness of captopril in preventing progression was higher within the subgroup of patients who had less severe CHF: the odds ratio was 0.12 (95% confidence interval = 0.03-0.45; p less than 0.01) for patients in NYHA class I or II on captopril and was 0.83 for those in class III. We conclude that the severity of CHF, as represented by the above-defined risk factors, is directly related to the likelihood for the development of progressive heart failure. However, the less severe the heart failure, the more effective the treatment with captopril will be in preventing disease progression. Thus, ACE inhibition has considerable potential for improving the prognosis of patients with mild heart failure.

Age Factors↗
PubMed1991

Are admission plasma fibrinogen levels useful in the characterization of risk groups after myocardial infarction treated with fibrinolysis?

The aim of our study was to prove or disprove the independent prognostic importance of fibrinogen after myocardial infarction. Plasma fibrinogen levels were determined on admission in 135 patients with an acute myocardial infarction and symptoms up to 4 h (mean: 1.8 h) immediately before starting fibrinolytic treatment with 1.5 mio U. streptokinase i.v. All patients were free from other diseases which are known to cause elevated fibrinogen levels. Coronary angiography was carried out in 87%. During a mean follow-up period of 26.2 months 31 coronary events could be observed in 26 patients: 18 reinfarctions, 6 cases of sudden death, and 7 coronary artery bypass graft surgeries because of new symptoms. While plasma fibrinogen levels were higher in smokers than in non-smokers (3.30 vs 2.94 g/l p = 0.011) and correlated with the number of involved coronary arteries (p = 0.08), values were similar in patients with and without coronary events during follow-up (3.07 vs 3.16 g/l, p = 0.70). This applied as well to univariate analysis as to multivariate Cox's regression model. We conclude that plasma fibrinogen levels determined very early in patients with acute myocardial infarction do correlate with other important prognostic variables, but have no independent prognostic importance.

Diagnostic Tests, Routine↗
PubMed1991

Cytokine production by mature and immature thymocytes.

We have studied the ability of subpopulations of activated thymocytes to produce four cytokines (IL-2, IL-4, IFN-gamma and TNF-alpha) which are believed to play roles in T cell development. Supernatants from various thymocyte subsets activated with calcium ionophore and PMA were tested for these cytokines. All CD3hi thymocyte subsets (CD4+8-, CD4-8- and CD4-8+) produced high titers of these four cytokines except CD3+4-8+ thymocytes, which did not produce IL-4. In contrast, CD4+8+ thymocytes did not produce any detectable cytokines. CD3-4-8- thymocytes produced IL-2, IFN-gamma, and TNF-alpha (but not IL-4) when activated by calcium ionophore + PMA and IL-1. We then separated CD3-4-8- thymocytes into IL-2R+ and IL-2R-. CD3-4-8-IL-2R+ thymocytes only produced small amounts of IL-2 when activated with calcium ionophore + PMA + IL-1, whereas CD3-4-8-IL-2R- thymocytes did not require IL-1 to produce IL-2, IFN-gamma, and TNF-alpha. Finally, CD4-8+3- thymocytes (an immature population believed to be an intermediate between CD3-4-8- and CD4+8+ thymocytes) only produced marginally detectable levels of IL-2 upon stimulation with calcium ionophore, PMA, and the addition of IL-1 did not result in increased levels of cytokine production. These observations indicate discrete patterns of cytokine production by the subsets studied and suggest specific controls of cytokine gene expression during T cell development.

Animals↗
PubMed1991

Antigen presenting ability of thymic macrophages and epithelial cells: evidence for defects in the antigen processing function of thymic epithelial cells.

We compared the antigen presenting ability of cloned thymic macrophage and epithelial cell lines using T cell hybridomas with well-characterized activation requirements. A cloned thymic epithelial cell line (3D.1), preinduced with interferon-gamma (IFN-gamma) activated the T cell hybridoma 3DO-18.3 but not the T cell hybridoma DO-11.10. Analyses using preprocessed antigen suggest that the failure of 3D.1 to activate DO-11.10 is due to its inability to process chicken ovalbumin to produce a peptide recognized by the Ag:MHC T cell receptor of DO-11.10. The epithelial cell line 3D.1 was able to activate DO-11.10 if the superantigen staphylococcal enterotoxin B was used for activation instead of ovalbumin. These observations indicate that IFN-gamma-induced 3D.1 expresses sufficient I-Ad molecules to activate DO-11.10 but is unable to produce the peptide of ovalbumin recognized by DO-11.10. Furthermore, 3D.1 appears to be representative of nonmacrophage thymic stromal cells cultured in vitro, since heterogeneous cultures containing epithelial cells exhibited the same selective T cell activation characteristics. In contrast, thymic macrophage cell lines activated all T cells studied. These results suggest that there is a functional difference between the capacity of thymic epithelial cells and macrophages to process and present antigen to T cells.

Animals↗
PubMed1991

C1-esterase inhibitor in uncomplicated pregnancy and mild and moderate preeclampsia.

Routine coagulation tests and measurement of the plasma levels of C1-esterase inhibitor (C1-INH) and antithrombin III were performed in 17 women with mild preeclampsia, 10 women with moderate preeclampsia and 20 women with uncomplicated pregnancy. All pregnant probands were within the third trimester of pregnancy. 20 non-pregnant women were used as controls. The groups were matched in age and the pregnant ones were also matched in gestational age. C1-INH activity and antigen were significantly reduced (p less than 0.002) in normally pregnant women as compared with non-pregnant ones. Further, C1-INH activity was lower in women with mild preeclampsia and significantly lower in women with moderate preeclampsia (p less than 0.05) as compared with normally pregnant women. None of the plasmatic coagulation tests was indicative of a consumption reaction. We conclude that C1-INH activity and antigen reductions are commonly associated with pregnancy. Furthermore, as markedly lower values can be found in mild and moderate preeclampsia, measurement of the C1-INH activity in pregnant women within the third trimester might proof useful to establish the diagnosis of a preeclamptic condition.

Adult↗
PubMed1991

Apolipoprotein A and prognosis after myocardial infarction in non-diabetic men.

The implications of apolipoproteins A-I and A-II for the prognosis of 178 non-diabetic men after acute myocardial infarction were studied. During a mean follow-up period of 4 years, one or more "coronary events" (nonfatal myocardial infarction, fatal coronary heart disease, coronary artery bypass graft surgery, deterioration of exercise ECG) were recorded in 37 patients. Serum levels of apolipoproteins A-I and A-II did not discriminate between patients with and without coronary events. This applied to the entire sample as much as to subgroups defined by presence or absence of interventions (coronary artery bypass graft surgery, long-term therapy with beta-blockers or lipid-lowering drugs). We conclude that coronary events in the first years after myocardial infarction cannot be predicted by apolipoprotein A-I or A-II levels.

Adrenergic beta-Antagonists↗
PubMed1991

Localization of type X collagen in canine growth plate and adult canine articular cartilage.

Type X collagen was extracted from ends of canine growth plates by pepsin digestion after 4 M guanidine hydrochloride extraction, purified by stepwise salt precipitation (2.0 M NaCl in 0.5 M acetic acid), and chromatographed on a Bio-Gel A1.5 M column in 1.0 M CaCl2. Without reduction on sodium dodecyl sulfate (SDS) polyacrylamide gels, the preparation yielded a single, high-molecular-weight (mol wt) band; after reduction, a single band of relative mol wt 5.0 x 10(4) was found. Polyclonal sera were raised against the purified collagen and used in the immunolocalization of canine type X collagen. As expected, indirect immunoperoxidase (IP) or indirect immunofluorescent staining with the polyclonal sera demonstrated that most of the immunoreactivity was localized in the zone of provisional calcification of the growth plate and in cartilage remnants in the metaphyseal region of the physis. A progressive decrease in staining toward the diaphysis of the fetal canine long bone was apparent as the trabecular structures were remodeled to bone. Unexpectedly, type X collagen was also detected in the zone of calcified, mature articular cartilage. It was concentrated in the pericellular matrix of the chondrocytes, appeared at or just above the tidemark, and was expressed immediately before mineralization. Identification of type X collagen in both the canine growth plate and the zone of calcified articular cartilage suggests that cells in the deep layer of cartilage and in the zone of calcified cartilage in the adult animal retain some characteristics of a growth plate and may be involved in regulation of mineralization at this critical interface. The expression of growth plate-like properties would allow the deep chondrocytes of mature articular cartilage to play a role in remodeling of the joint with age and in the pathogenesis of osteoarthritis.

Animals↗
PubMed1991

Metaiodobenzylguanidine (mIBG) in treatment of 47 patients with neuroblastoma: results of the German Neuroblastoma Trial.

From 1984 to 1989, 47 children with relapsed, refractory, and/or metastasized neuroblastoma were treated with 131I-metaiodobenzylguanidine (mIBG) in several different treatment combinations. At initial diagnosis, 36 children had Evans stage IV and 11 stage III disease. In 16 of the 47 children, tumor recurred after complete remission prior to mIBG treatment, 26 of 47 progressed from residual or nonresponding tumor, and in 5 of 47 tumor progression during chemotherapy was observed. Altogether the children were treated with a total of 112 courses (range 1-6) with a mean dosage of 8.9 +/- 6.7 mCi/kg body weight/treatment course. Total dose was 283.2 +/- 203.7 mCi for stage III and 388.9 +/- 218.6 mCi for stage IV. Nine of 47 children reached a complete or a very good partial remission (CR and VGPR) from mIBG treatment alone, 13 of 47 achieved partial remission (PR). In an early analysis, 10 patients treated with mIBG in the neuroblastoma trial NB 85 of the German Society of Pediatric Oncology showed no significant difference in survival time compared with 30 conventionally treated children. However, the recent therapy series has been done with higher doses of mIBG, and during improved therapeutic scanning many more bone lesions could be detected than during earlier diagnostic scanning. We conclude that mIBG treatment has not yet fulfilled the expectations for it but still seems for certain indications to be a promising tool to treat neuroblastoma in the future. Moreover, the frontier of neuroblastoma detection is still advancing.

3-Iodobenzylguanidine↗
PubMed1991

Hemoglobin dynamics in rat erythrocytes investigated by Mössbauer spectroscopy.

Rats have been enriched in 57Fe and erythrocytes were isolated from the blood. Mössbauer absorption spectroscopy on the hemoglobin of these erythrocytes has shown rather similar dynamics as found earlier in crystals of myoglobin, in frozen solutions of human hemoglobin and in a number of other proteins. The results strongly indicate that the motion of the heme and presumably some part of the F-helix is mainly influenced by the average viscosity of the sample determined by a network of hydrogen bridges and other weak interactions. Extrapolations of Mössbauer results from protein crystals to proteins in their physiological surroundings seem to be suitable for heme proteins.

Animals↗
PubMed1991

Tendinous insertions in the human thyroid cartilage plate: macroscopic and histologic studies.

The zones of tendinuous insertion and origin of the sternothyroid muscle, the thyrohyoid muscle, the inferior constrictor muscle of the pharynx and the external part of the cricothyroid muscle were studied in adult larynges by macroscopy and light microscopy. The sternothyroid muscle is inserted in the superior and inferior thyroid tubercula and also in a tendinous arch, which extends between the two tubercula. In contrast to the descriptions found in most textbooks, the sternothyroid muscle has no attachment to the oblique line. The thyrohyoid muscle and the thyropharyngeal part of the inferior constrictor muscle of the pharynx originate in ventral and dorsal symmetry at the oblique line. X-rays permit a measurement of their original angles, resulting in a mean value of 36 degrees. According to these measurements, and electromyographic findings by other authors, both muscles can be regarded as a bipennate muscle from a functional point of view. Histologic studies indicate that the oblique line's zone of origin structurally resembles an areal periosteal-diaphysary tendinous insertion. In the non-ossified thyroid cartilage, the insertions in the region of the thyroid tubercula are similar to chondral-apophysary insertions of tendons in the limb skeleton. After ossification of the thyroid cartilage, they show the shape of circumscribed periosteal-diaphysary insertions. Osteogenesis of the laryngeal skeleton therefore affects the structure of the thyroid tubercula's tendinous insertions. From a mechanical point of view, the insertions in the thyroid cartilage function as extension-checking mechanisms, and also serve to balance the different elastic modules of the tendinous tissue and the cartilaginous or bony tissue.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Uncoated polyethylene RM acetabular component versus Müller cemented acetabular component. A 4- to 8-year follow-up study.

Comparable patient populations with 160 uncoated RM acetabular cups and 263 cemented Müller standard acetabular cups were submitted to survival-time analysis in a retrospective study with a mean follow-up of 5.3 years for the RM cup and 6.1 years for the Müller cup. After 7-8 years 12% of the RM cups and 4% of the Müller cups had been exchanged, 40% and 15% respectively were loose. The poor performance of the RM cups is ascribed to additional external polyethylene wear, which leads to the formation of granulomas and destroys the weight-bearing osseous structures. Similar granulomas also develop on the proximal stem and thus endanger the same.

Aged↗
PubMed1991

Phaeochromocytoma and functioning paraganglioma in childhood and adolescence: role of iodine 131 metaiodobenzylguanidine.

Phaeochromocytomas and functioning paragangliomas are rare tumours in childhood and adolescence. We review our experience of 43 cases (24 men, 19 women) who were first diagnosed at the age of less than or equal to 18 years. All patients were evaluated at some point in their illness with iodine 131 metaiodobenzylguanidine (131I-mIBG) scintigraphy. Eight patients (19%) had bilateral adrenal tumours, 12 (28%) had solitary extra-adrenal tumours, and 8 (19%) had multiple tumours. In 10 patients (23%), the tumours were associated with a familial neurocristopathic syndrome. Thirteen of 24 (54%) unifocal tumours which were initially considered to be benign ultimately proved to be multi-focal and/or malignant. The final prevalence of malignancy was 60%--26 patients, of whom only 15 (57%) had obviously malignant tumours at the time of diagnosis. Primary tumour size greater than or equal to 5 cm was more commonly associated with a malignant course in adrenal but not extra-adrenal tumours. No other clinical, biochemical or morphological characteristic was significantly associated with malignancy. Although the high prevalence of malignancy in this series at least partly reflects referral bias, the need for lifelong follow-up of these patients is underscored. 131I-mIBG scintigraphy was positive in 36 patients (84%), with a somewhat lower false-negative rate (12%) than X-ray computed tomography (20%). Eight patients with malignant tumours received therapeutic doses of 131I-mIBG, with partial tumour responses in 3. Thus, 131I-mIBG is an efficacious, non-invasive, localising agent and may be considered as a palliative therapeutic agent when alternatives have failed.

3-Iodobenzylguanidine↗
PubMed1991

Diagnosis of poststernotomy infection: comparison of three means of assessment.

Of 737 adults undergoing cardiac operations through a median sternotomy over a 2-year period (January 1988 to January 1990), sternal-substernal space infection requiring mediastinal exploration developed in 8. Six of these patients as well as 18 additional patients were evaluated for possible poststernotomy wound infection by computed tomography (4 true positive, 4 false positive, 10 true negative, 2 false negative), indium-111 leukocyte scanning (5 true positive, 0 false positive, 18 true negative, 1 false negative), and epicardial pacer wire cultures (6 true positive, 1 false positive, 12 true negative, 0 false negative). On the basis of this experience it is suggested that in addition to computed tomography, indium-111 leukocyte scanning and epicardial pacer wire cultures may be useful in the diagnosis of poststernotomy deep wound infection.

Humans↗