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Biomedical subjects

C Müller

Publications and source records attributed to C Müller.

At least 523 records · Page 29Linked to original sources
PubMed1990

Viral reactivation as a cause of unexplained fever in patients with progressive metastatic breast cancer.

Patients suffering from metastatic breast cancer and recurrent fever were investigated for viral reactivation or new viral infection as a possible cause of these febrile episodes. Three groups of patients were included in the study: (a) patients under adjuvant chemotherapy with cyclophosphamide, methotrexate and fluoruracil, (b) patients with stable metastatic disease treated with cyclophosphamide, fluoruracil and Adriamycin or mitoxantrone and (c) patients with progressive metastatic disease who also received the latter treatment. During the time of observation, patients under adjuvant chemotherapy did not present with fever or asymptomatic viral reactivation or bacterial infections at all. Out of 7 patients with stable disease, 2 had bacterial infections that coincided with the leukocyte nadir, and 1 presented with asymptomatic reactivation of cytomegalovirus. In contrast, fever in 9 of 11 patients with progressive disease was associated with a reactivation of herpes simplex virus (HSV) and in 3 of them with a consecutive reactivation of varicella zoster virus (VZV). The increase in complement-fixing anti-HSV or anti-VZV antibodies occurred in close association with a rise of the respective preexisting antibodies of the IgG class. In addition, HSV-infected cells were recovered from the urine of 7 patients with progressive disease further corroborating the serological data. Incidentally, natural killer cell activity, which has been postulated to be connected with the defense against viral infections, was found to be significantly lower in the group of patients with progressive disease, as compared to the group of patients under adjuvant chemotherapy (P less than 0.05) or to the group of patients with stable disease (P less than 0.05). We conclude that unexplained fever in patients with progressive metastatic breast cancer may result from viral reactivation.

Antibodies, Viral↗
PubMed1990

Susceptibility of autologous target cells to lysis by lymphokine-activated effectors from interferon-alpha-treated chronic myelogenous leukaemia patients.

Chronic myelogenous leukemia (CML) patients in chronic phase display compromised lymphokine-activated killer (LAK) cell induction, which is partly restored after therapy with interferon alpha. However, the relative resistance of the leukemic cells from these patients to autologous or allogeneic LAK lysis is not affected by this treatment. In an attempt to render CML cells more susceptible to lysis or cytostasis, they were precultured in serum-free medium with or without recombinant growth factors. In eight patients studied, interleukin-3 (IL-3) significantly enhanced the spontaneous short-term (6-day) proliferation of CML cells, with retention of ability to form colonies in methylcellulose. Culture in either medium alone or IL-3 led to a significant enrichment of CD14+ and CD33+ cells but to a reduction in CD34+ cells. In contrast, culture of the same cells in IL-2 (to generate autologous LAK activity) resulted in a loss of CD14+ and CD33+ as well as CD34+ cells but in a significant increase in CD3+ and CD56+ cells. Despite similarities in their phenotypes, IL-3 cultured cells but not those cultured in medium alone acquired susceptibility to lysis by the IL-2-cultured autologous LAK cells. These results may have significance for the design of novel combination immunotherapy in CML.

Antigens, Surface↗
PubMed1990

Involvement of CD45 in MHC class II-allospecific cytotoxicity.

Twenty-seven different CD45 monoclonal antibodies (mAb) were assessed for their ability to block cytotoxicity of alloreactive CD4+ MHC class II-specific or CD8+ class I-specific human T cell clones (n = 3 and 5, respectively). Twelve of 27 blocked the former but only 1/27 the latter, although all 27 significantly inhibited MHC-unrestricted lysis of K562 cells by either CD4+ or CD8+ clones. MAb pretreatment of effector cells but not target cells resulted in retention of blocking. Crosslinking the CD45 with goat anti-mouse Ig serum did not result in blockade of lysis by class I-specific clones or reveal blocking of class II-specific clones not inhibited by mAb alone. These results suggest that CD45 molecules may be predominantly involved in MHC class II-specific but not class I-specific allocytotoxicity as well as MHC-unrestricted natural killer-like cytotoxicity.

Antibodies, Monoclonal↗
PubMed1990

Complete nucleotide sequence of a simian immunodeficiency virus from African green monkeys: a novel type of intragroup divergence.

We have determined the entire nucleotide sequence of a full-length molecular clone, termed SIVagm3, which is infectious in vitro and in vivo. The genomic organization was found to be similar to other immunodeficiency viruses of human and simian origin. Comparison of SIVagm3 with SIVagmTYO-1, the only other completely sequenced molecular SIVagm clone, revealed a novel type of intragroup divergence, which is characterized by (1) an unusually high degree of variability in pol in relation to gag and env and (2) a high degree of divergence in the rev and tat genes. Thus, since SIVagm3 and SIVagmTYO-1 evolved from their common ancestor, they diverged in a different manner than human immunodeficiency viruses. Hypervariable regions in env were defined and shown to be relatively restricted in comparison to HIV-1 and HIV-2.

Amino Acid Sequence↗
PubMed1990

Soluble interleukin-2 receptor and soluble CD8 antigen in active rheumatoid arthritis.

Concentrations of soluble interleukin-2 receptor (sIL-2R) and of soluble CD8 antigen (sCD8) in sera and in supernatants of phytohemagglutinin (PHA)-stimulated peripheral blood mononuclear cells (PBMC) derived from patients with active rheumatoid arthritis (RA) were studied. sIL-2R concentrations in sera derived from patients with RA (1484 +/- 382 U/ml) were significantly higher than in sera derived from healthy controls (380 +/- 110 U/ml; P less than 0.0005). In contrast, supernatants of PHA-stimulated PBMC derived from patients with RA contained similar amounts of sIL-2R (727 +/- 467 U/ml) as those derived from healthy control individuals (833 +/- 508 U/ml; P greater than 0.1). When investigated for the presence of sCD8 antigen, sera derived from patients with RA contained significantly lower amounts (30 +/- 28 U/ml) than sera derived from healthy controls (405 +/- 136 U/ml; P less than 0.0005). Similarly, PHA stimulation of PBMC derived from patients with RA resulted in a significantly lower production of sCD8 (35 +/- 46 U/ml) as compared to the one obtained by PHA stimulation of PBMC derived from healthy controls (177 +/- 59 U/ml; P less than 0.0005). This difference could not be explained by a lower proliferative response to PHA by PBMC derived from patients with RA (21,474 +/- 14,022 cpm) as compared to healthy controls (29,549 +/- 11,188 cpm; P greater than 0.05). Our data demonstrate that PBMC derived from patients with active RA differ from PBMC derived from healthy individuals concerning their ability to produce sIL-2R and sCD8.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1990

Decreased serum osteocalcin levels in patients with liver cirrhosis.

Serum levels of osteocalcin (OC) have been found to be a specific biochemical parameter of bone formation. We measured serum levels of osteocalcin, parathyroid hormone (PTH) and 25-hydroxyvitamin D (25(OH)D) in 49 patients with liver cirrhosis, who are known to have an increased prevalence of metabolic bone disease, and a matched control group (n = 35). Serum levels of OC were significantly decreased in the patients with liver cirrhosis when compared to control subjects (P less than 0.001). Serum levels of 25(OH)D were decreased (P less than 0.001), whereas no statistical difference was found between the serum levels of PTH in the patients with liver cirrhosis and those of the controls. In a subgroup of 23 patients with cirrhosis of the liver and 34 control subjects, the bone mineral content (BMC) of the non-dominant forearm was determined by single photon absorptiometry. BMC was significantly lower in the patient with liver cirrhosis than the control subjects (P less than 0.04). Our data demonstrate vitamin D deficiency, decreased bone formation and a decreased BMC in patients with liver cirrhosis.

Bone Density↗
PubMed1990

Bone mineral mass associated with postmenopausal vertebral deformities.

Vertebral morphometry on thoracic and lumbar spine radiographs and bone mass measurements were carried out on 215 patients investigated for postmenopausal osteoporosis. Bone mineral mass was measured on the central third of the skeleton by neutron activation analysis and the result, normalized for body size, expressed as a calcium bone index (CaBI). The normal CaBI value for females (20-40 years) is 0.97 (0.11) with a lower limit for these young, normal women, of 0.75. Vertebral compression deformity was defined as a mean height more than 15% lower than adjacent normal vertebrae. Thoracic and lumbar anterior wedge deformities and central compression were defined as anterior/posterior (A/P) or mid/posterior (M/P) height ratios of less than 0.75. For the 129 patients without vertebral deformities, the mean CaBI was 0.80 (0.12) (1 SD) and 32% of these patients had CaBI values below the normal young adult range (CaBI less than 0.75). In 20 patients, vertebral deformities were limited to 1 or 2 mid-thoracic vertebrae, and the mean CaBI values for these 20 patients was 0.81 (0.15), equal to that for patients without any vertebral deformity. For the remaining 67 patients, (i.e., patients with one or more vertebral deformities involving at least one distal thoracic or one lumbar vertebra) the mean CaBI value was 0.66 (0.10), 17% below the value for patients without vertebral deformities. Low CaBI values (CaBI less than 0.75) were observed in 87% of these patients, consistent with the diagnosis of osteoporotic fractures. Based on our CaBI results, however, mid-thoracic deformity was not associated with significant osteopenia and is not, therefore, diagnostic of osteoporotic fracture.

Adult↗
PubMed1990

The consequences of tubulo-interstitial changes for renal function in glomerulopathies. A morphometric and cytological analysis.

Morphometric investigation of the structures of the cortex in kidneys exhibiting various types of glomerulopathy revealed the following: 1. In various types of glomerulonephritis, diabetic glomerulosclerosis, and glomerular amyloidosis there are significant correlations between the severity of fibrosis of the renal cortical interstitium and tubular atrophy resulting from chronic interstitial inflammation, and the serum creatinine concentration, creatinine clearance, inulin clearance and PAH clearance. 2. As illustrated with the example of membranoproliferative glomerulonephritis type I, if glomerulopathy alone is present, there is no elevation of the serum creatinine concentration, even if the glomerular inflammatory changes are severe; neither are severe renal amyloidosis that is confined to the glomeruli and severe isolated diabetic glomerulosclerosis associated with elevation of the serum creatinine concentration. 3. There is a significant negative correlation between the severity of interstitial fibrosis resulting from chronic inflammation and the total number and cross-sectional area of the intertubular capillaries; i.e., the total cross-sectional area and number of capillaries per unit area decrease as the fibrosis of the cortical interstitium increases. 4. Cases of glomerulonephritis in which there is accompanying fibrosis of the renal cortical interstitium have a significantly worse long-term prognosis than those in which there is only severe glomerulitis. 5. Obliteration of the post-glomerular capillaries leads to an increase in the cross-sectional area of the glomerular capillary convolution, the morphological equivalent of an increase in intraglomerular pressure. 6. The cause of the disease of the renal cortical interstitium that may accompany the various types of glomerulonephritis is not known. It is considered possible, as a working hypothesis, that this inflammation represents a T-cell stimulated autoimmune process in which fibroblast proliferation occurs, leading to an increase in numbers of fibrocytes in the renal cortical interstitium and thus to increased production of collagen.

Creatinine↗
PubMed1990

Decreased hepatic function in patients with hepatoma or liver metastasis monitored by a hepatocyte specific galactosylated radioligand.

99mTc-galactosylated neoglycoalbumin (99mTc-NGA) is a hepatocyte-specific tracer that, after injection into the blood stream, delivers radioactivity selectively to the liver. This is based upon chemical recognition and binding by the hepatic binding protein (HBP), a receptor specific for galactosylated glycoproteins. Liver tissue samples were obtained intraoperatively from patients undergoing surgery for various cancers. The concentration of specific HBP receptors in the liver (normal liver, hepatoma, liver metastasis) was calculated from the in vitro binding of 99mTc-NGA. One week after surgery, the in vivo HBP density was also measured in some of these patients after injection of 3.5 mg (50 nmol per patient) 99mTc-NGA (150-200 MBq) for simulation of 99mTc-NGA kinetics. Comparison of in vitro and in vivo HBP concentration in the liver showed values in the same concentration range. In patients with hepatoma or liver metastasis a significantly (P less than 0.01) decreased global HBP density was found in vivo compared to controls. The values obtained for in vivo HBP concentration in the liver amounted to 0.38 +/- 0.05 mumol l-1 liver for patients with hepatoma, to 0.4 +/- 0.1 mumol l-1 in patients with liver metastasis and to 94 +/- 0.05 mumol l-1 liver in cancer patients without liver malignancy. In vitro investigation of HBP density revealed the malignant liver tissue to have a significantly (P less than 0.0001) decreased or almost (completely) absent HBP receptor density compared to the normal tissue apart from the cancer area. It is concluded that determination of HBP density in vivo via a specific tracer is a new, simple and reliable approach for the determination of remaining hepatic function in patients with primary or secondary liver cancer.

Aged↗
PubMed1990

99mTc-neoglycoalbumin (NGA)-binding to human hepatic binding protein (HBP) in vitro.

1 Neoglycoalbumin (NGA) was synthesised by covalent coupling of 2-imino-2-methoxyethyl-1-thio-beta-D-galactopyranoside (IME-thiogalactose) to the primary amino groups of human serum albumin (HSA). NGA was purified by ultrafiltration and size exclusion h.p.l.c. (SEC). 99mTc-labelling was performed with and without SEC purification. 2 Estimation of 99mTc-NGA-binding to human hepatic binding protein (HBP) revealed a complex behaviour indicating saturable high- and low-affinity sites. The high-affinity binding capacity was 1.1 +/- 0.4 pmol mg-1 human liver plasma membrane protein, the low-affinity binding capacity was 6.2 +/- 1.8 pmol mg-1 liver plasma membrane protein. The apparent equilibrium dissociation constants were 2.4 +/- 1.2 and 18.4 +/- 4.8 nM, respectively. 3 Specific binding of 99mTc-NGA to human HBP in the presence of 100 microM unlabelled NGA, Ca++ and Mg++ at pH 7.5 and 37 degrees C reached 85 +/- 5% at equilibrium. The amount of ligand specifically bound increased with the amount of human liver membrane protein added. The concentration of unlabelled agonist necessary to displace 50% of ligand bound amounted to 100 nM.

Albumins↗
PubMed1990

Modulation of leucocyte locomotion by interleukin-1.

The influence of interleukin-1 (IL-1) upon leucocyte locomotion in vitro was studied, using either casein or zymosan-activated serum (ZAS) as chemotaxigens. A pre-incubation of polymorphonuclear cells (PMNC) with ultrapure (purity 99%) human IL-1 (1 U/ml) for 2 and 5 h followed by a washing step resulted in a significant decrease in leucocyte locomotion against casein (P less than 0.0005 and P less than 0.01, respectively), but not against ZAS (P greater than 0.1). Moreover, the direct addition of this IL-1 preparation to leucocyte locomotion assays without pre-incubation produced a similar and significant inhibition of leucocyte locomotion directed against casein (P less than 0.05). This inhibitory effect could not be augmented further by higher concentrations of ultrapure IL-1. In order to exclude the effect of possibly contaminating cytokines in the ultrapure IL-1 preparation used, additional assays with recombinant human IL-1 (rIL-1) alpha and rIL-1 beta (1 U/ml) were performed to investigate their influence upon leucocyte locomotion. It was found that both rIL-1 alpha and rIL-1 beta inhibited leucocyte locomotion directed against casein significantly (P less than 0.005). Similar to the previous experiments, leucocyte locomotion could not be further inhibited by higher concentrations (10 U/ml) or rIL-1. Thus, both ultrapure and rIL-1 were found to have the ability to inhibit leucocyte locomotion in vitro.

Caseins↗
PubMed1990

Gas supply across membranes in bioreactors for hepatocyte culture.

The conditions required for hepatocyte cultures is a main topic in the development of bioreactors for hybrid liver support systems. The detoxification of ammonia and the synthesis of urea due to primary isolated hepatocytes was measured in order to compare two different models of gas supply in bioreactors: (a) indirect medium oxygenation and (b) direct membrane-contact oxygenation of the hepatocytes using polypropylene membranes. Increasing oxygen pressure promoted cell function. At day 6 of culture, urea synthesis was 0.8 +/- 0.3 mM in 21% of O2 cultures and 1.5 +/- 0.1 mM in oxygenated cultures. Alkalosis due to CO2 loss decreased ammonia metabolism. The direct membrane-contact oxygenation resulted in enhanced cell metabolism in comparison to medium oxygenation: urea synthesis at day six was 1.42 +/- 0.2 mM in 21% O2 cultures. Polypropylene oxygenation membranes proved to be sufficient for hepatocyte adhesion. Two functions can be integrated in one element in liver support systems using the investigated polypropylene membrane and the direct membrane-contact oxygenation: oxygenation with physiological oxygen pressure in bioreactors due to gas supply across the membrane and adhesion of hepatocytes in bioreactors on the membrane.

Animals↗
PubMed1990

Phenotypic analysis of lymphocytes involved in major histocompatibility complex unrestricted cellular cytotoxicity in patients with alcoholic cirrhosis.

Lymphocyte subpopulations known to exert major histocompatibility complex (MHC) unrestricted cytotoxicity were enumerated in 33 patients with alcoholic cirrhosis and in 10 patients with alcohol-induced fatty changes of the liver. Absolute numbers and percentages of lymphocytes bearing the CD57 (median 12 vs. 20%; p = 0.007) and CD16 (median 12 vs. 19%; p = 0.0027) antigens were significantly reduced in cirrhotic patients as compared to healthy control individuals, whereas no significant change in CD56+ cells (median 13 vs. 13%; n.s.), comprising a subpopulation with a high natural killer activity in normal individuals, was observed. A subset of these cells, cytotoxic T cells coexpressing CD56 and CD3 antigens and capable of MHC-unrestricted cellular cytotoxicity, was significantly increased in patients with alcoholic cirrhosis as compared to healthy control individuals (median 2 vs. 1%; p = 0.024). Patients with alcohol-induced fatty changes of the liver did not show any deviation of lymphocyte subpopulation from normal. The finding that lymphocyte subsets capable to exert most of the MHC-unrestricted cytotoxic capacity in peripheral blood (CD56+ non-T-cells and CD3+ CD56+ T cells) were unchanged or even increased in number suggests that the reduced natural killer cell activity known to occur in patients with alcoholic liver cirrhosis might be due to a functional defect of these cells. Furthermore, our results indicate that changes in frequency of MHC-unrestricted cytotoxic cells are not found in a similar manner in all subsets of these cells, but are dependent on the particular cell surface marker investigated.

Adult↗
PubMed1990

Human endolymphatic sac: evidence for a role in inner ear immune defence.

In an immunohistochemical study, monoclonal and polyclonal antibodies have been used to identify cells and structures in the extraosseous part of endolymphatic sacs (ES) which were removed at autopsy from 30 persons. Intraluminal, intraepithelial, intravascular and perisaccular cells expressed the leukocyte common antigen. Immunostaining with antibodies against the CD4 and CD8 antigens revealed the predominance of CD4-positive T lymphocytes in the ES. A few lymphoid cells were found to express the major histocompatibility antigen class II. Interdigitating cells of the Langerhans type were rarely found in the epithelial layer. B lymphocytes were present in the lumen and the stroma of the ES and IgA- or IgG-containing cells in the stroma only. IgA, secretory component and the J chain were detected within epithelial cells and in the lumen of the ES. Macrophages were observed in the lumen and the stroma. Our findings are in accordance with previously published data in animals and man and give further evidence of an important role of the ES in inner ear immune defence.

Antibodies, Monoclonal↗
PubMed1990

[Acute phase reaction in acute viral hepatitis].

We investigated serum concentrations of acute-phase-proteins (alpha 1-antitrypsin (alpha 1-AT), alpha 1-acid glycoprotein (alpha 1-sGP) and C-reactive protein (CRP)), and of complement components C3 and C4 during the course of acute hepatitis A and hepatitis B and correlated it to age and sex of the patients. Whereas a small increase of all three acute-phase-proteins was seen during acute hepatitis A, alpha 1-AT and CRP, but not alpha 1-aGP were found to be elevated during hepatitis B. A moderate elevation of C3 and C4 serum levels, more pronounced in hepatitis B than in hepatitis A, was seen followed by a slow return to normal. A systemic acute phase response seems not to be present during acute viral hepatitis in spite of the pronounced local inflammatory changes in liver tissue.

Acute-Phase Proteins↗
PubMed1990

Psoriasis induced at the injection site of recombinant interferon gamma. Results of immunohistologic investigations.

Recombinant human interferon gamma used for treatment of psoriatic arthritis was found to induce expression of HLA-DR, but not HLA-DP or HLA-DQ, on keratinocytes at the site of injection. Some patients showed an improvement of their joint symptoms, but the cutaneous manifestations remained unaffected. In 10 of 42 patients, punctiform psoriatic foci could be induced at the site of injection of interferon gamma. For this presentation, we selected a female patient with psoriatic arthropathy and type II diabetes mellitus in whom psoriasis was induced at the site of application of interferon gamma, but not after subcutaneous injection of insulin or placebo. We conclude that interferon gamma is an important lymphokine in the development of psoriasis.

Abdomen↗