Salivary and serum levels of electrolytes and immunomarkers in edentulous healthy subjects and in those with rheumatoid arthritis

Summary Chemical analyses of serum and stimulated parotid saliva of 73 edentulous patients with rheumatoid arthritis (RA) and of 36 edentulous healthy controls were performed. The purpose of the present work was to assess the possible correlations between the concentrations of electrolytes and immunomarkers such as lysozyme, IgA, ₂-microglobulin (₂-m) and rheumatoid factor (RF) in serum and saliva. The results of the chemical analyses of the serum showed elevated values for IgA, IgM, lysozyme and ₂-m. In addition 45 patients were positive for rheumatoid factor. In saliva, the only significant difference between the groups studied was decreased potassium concentration in the RA patients. Nine salivary specimens were RF positive. There was a highly significant correlation between serum ₂ and salivary IgA, lysozyme, ₂-m, urea and amylase in the RA patients. In addition, serum lysozyme and RF were related to salivary ₂-m and urea. However, no such relations could be observed in the controls. These findings indicate that serum immunomarkers have an effect on the salivary constituents in the patients with an altered immunological state. The importance of simultaneous serum analysis is emphasized when salivary levels are to be interpreted.     

The levels of memory (CD45RA−, RO+) CD4+ and CD8+ peripheral blood T-lymphocytes correlate with IgM rheumatoid factors in rheumatoid arthritis

We investigated whether, in rheumatoid arthritis (RA), the CD45 isoform expression of peripheral blood T-lymphocytes (T-PBL) is related to auto-immune processes (e.g. IgM rheumatoid factors) and to clinical manifestations. By three-colour flow cytometry, we quantified three subsets of CD4+ or CD8+ T-PBL: naive CD45RA+,RO–, transient CD45RA+,RO+, and memory CD45RA–,RO+ cells, in 102 patients with RA and in 41 age- and sex-matched controls. The serum levels of rheumatoid factors (RF) were determined — besides conventional agglutination tests — by ELISA (IgM-RF). Extensive clinical examination was performed at the time of blood sampling. In RA, age, sex and drug therapy did not constitute major influences on the CD45RA/RO patterns. In healthy men, higher age significantly correlated with fewer naive and more memory CD4+ T-PBL (P<0.01). In RA, distinct correlations between the T-PBL subsets, autoimmune and clinical manifestations became obvious when patients with low and high levels of RF against human IgG Fc fragments, as determined by ELISA, were analysed separately. RA patients with high IgM-RF had elevated proportions of CD45RO+ T-PBL (P<0.05), that correlated with clinical parameters of disease activity (tender joint count, Ritchie index, P<0.05) and outcome (Health Assessment Questionnaire, Larsen radiographic scores, P<0.05). The proportions of memory CD4+ and CD8+ T-PBL correlated strongly (P<0.001) with the IgM-RF levels. Within 1 year, only three of 34 patients (disease duration of 5–9 years) showed seroconversion from low to high levels of IgM-RF (and positive agglutination tests); this was paralleled by reductions in naive and increases in transient T-PBL (P<0.02). Thus, in RA, the proportions of memory CD4+ and CD8+ T-PBL correlate with the level of IgM-RF and, together with transient T-PBL, with clinical parameters of disease activity and outcome.     

Lymphocyte subpopulations in rheumatoid arthritis

Summary Peripheral blood lymphocytes (PBL) and synovial fluid lymphocytes (SFL) of patients with rheumatoid arthritis (RA) were examined with monoclonal antibodies, with coated ox red blood cells for the expression of Fc receptors for IgG or IgM (T and T cells), and incubated for the demonstration of -naphtyl acetate esterase and acid phosphatase.Equal percentages of OKT4 and OKT8 PBL were found in clinically active and inactive RA patients, and in healthy controls, but decreased percentages of OKT4 and increased percentages of OKT8-positive lymphocytes were found among the SFL.The percentages of T and T cells, the presence of HLA-DR membrane antigens on T lymphocytes as well as the staining pattern for the enzymes revealed that SFL of patients with RA were highly activated, compared to PBL of RA patients and healthy controls.It can be concluded from this study that a single determination of OKT4 and OKT8-positive lymphocytes in the peripheral blood of RA patients has no predictive value for disease activity. However, the results of the experiments on T lymphocyte-activation clearly showed preferential activation of SFL compared to PBL, indicating that activation of lymphocytes occurs at the site of inflammation.     

Serum cytokines in patients with rheumatoid arthritis

Serum cytokines such as interleukin 1 (IL-1), interferon (IFN-), and tumor necrosis factor (TNF) were measured in 40 patients with rheumatoid arthritis (RA). In the 40 patients studied, serum IL-1 was detected in 5 patients, IFN- in 10 patients, and TNF in 20 patients. The IL-1-positive group showed increased values of activity indices compared to the IL-1-negative group. Values of serum IFN- correlated well with the number of peripheral blood lymphocytes and CD3⁺ cells and with the percentage of CD3⁺ CD26⁺ cells. Values of serum TNF correlated positively with the number of peripheral blood monocytes and the percentage of CD3⁺ HLA-DR⁺ and CD3⁺ CD25⁺ cells. These results indicated that serum IL-1 in RA patients reflects the activity of RA, while the serum IFN- and TNF in RA patients may be related to circulating activated lymphocytes and monocytes, respectively.     

Secretory component and lactoferrin in pure pancreatic juice in chronic pancreatitis

To evaluate pathophysiological roles of proteins in pancreatic secretion, immunoreactive lactoferrin (LF) and secretory component (SC) were measured in the first fraction of the pure pancreatic juice obtained endoscopically from 17 control, 21 suspected (SCP), 14 noncalcified (NCP), and 14 calcified chronic pancreatitis (CCP) subjects. The protein and amylase tended to decrease both in concentration and output from control to CCP. LF concentration was elevated in CCP (18.0±4.9/ml) when compared with controls (2.3±0.2g/ml), and LF output in NCP (12.3±3.8 g/min) was increased from controls (3.8±0.6 g/min). The combination of high LF concentration with low protein output was observed in 10/14 in CCP but 0/14 in NCP and can be a biochemical discriminator of CCP from NCP. SC concentrations were also elevated in NCP (8.5±2.0 g/ml) and CCP (5.6±1.6 g/ml) from controls (1.2±0.2 g/ml). SC outputs in SCP (9.8±3.1 g/min) and NCP (21.1±4.8 g/min) were increased from controls (1.7±0.3 g/min), but there was no further increase in CCP. Hypersecretion of LF and SC in chronic pancreatitis is different, especially in CCP, although the mechanisms for hypersecretion are unknown.This study was supported in part by a research grant for intractable pancreatic disease from the Ministry of Health and Welfare, Japan.     

Effects of short-term high dose intake of evening primrose oil on plasma and cellular fatty acid compositions, α-tocopherol levels,and erythropoiesis in normal and Type 1 (insulin-dependent) diabetic men

Summary In addition to their usual diet, nine Type 1 (insulin-dependent) diabetic men and ten male control subjects took 20 g d,ga-tocopheryl acetate enriched evening primrose oil (14.45 g 182c,6, 1.73g 183c,6, 400 mg d,-tocopheryl acetate) daily for one week. At start, diabetic patients had more 140, 150 and 18 2c,6, and less 160, 161c,7, 181c,7, 183c,6, 203c,9, 203c,6, 204c,6 and 226c,3 in plasma, erythrocytes and/or platelets. Furthermore, they had lower 161c,7/160, 181c,7/160, and 204c,6/203c,6 ratios and a higher 203c,6/183c,6 ratio. In diabetic patients, -tocopherol levels in erythrocytes were lower, whereas those in plasma were normal. In both groups, oil intake changed fatty acid profiles. Most markedly, 203c,6 increased, whereas the ratios 203c,6/ 183c,6 and 204c,6/203c,6 decreased. 204c,6 increased in control subjects, but not in diabetic patients. Erythrocytes and platelets responded differently in their fatty acid profiles, -tocopherol rose in plasma and, although less for diabetic patients, in erythrocytes. In diabetic patients as well as in control subjects, erythrocyte count, haemoglobin level, mean corpuscular haemoglobin content and concentration increased and glycosylated haemoglobin percentage decreased without an apparent decline in blood glucose levels. Plasma -thromboglobulin and platelet factor 4 decreased, especially in diabetic patients. In conclusion, diabetic patients had abnormal fatty acid patterns, suggesting an impaired 9, 6 and 5 desaturation and an enhanced chainelongation, and had lower erythrocyte a-tocopherol levels; and short-term high dose intake of evening primrose oil increased 203c,6 in both groups, but 204c,6 only in control subjects, gave fatty acid responses which were different for erythrocytes and platelets, enhanced erythropoiesis, and lowered indices of in vivo platelet activation.     

Weakened cellular scavenging activity against oxidative stress in diabetes mellitus: regulation of glutathione synthesis and efflux

Summary Glutathione functions to scavenge oxidants or xenobiotics by covalently binding them and transporting the resulting metabolites through an adenosine 5-triphosphate-dependent transport system. It has been reported that the intracellular concentration of glutathione decreases in diabetes mellitus. In order to elucidate the physiological significance and the regulation of anti-oxidants in diabetic patients, changes in the activity of the glutathione-synthesizing enzyme, -glutamylcysteine synthetase, and transport of thiol [S-(2,4-dinitrophenyl)glutathione] were studied in erythrocytes from patients with non-insulin-dependent diabetes and K562 cells cultured with 27 mmol/l glucose for 7 days. The activity of -glutamylcysteine synthetase, the concentration of glutathione, and the thiol transport were 77%, 77% and 69%, respectively in erythrocytes from diabetic patients compared to normal control subjects. Treatment of patients with an antidiabetic agent for 6 months resulted in the restoration of -glutamylcysteine synthetase activity, the concentration of glutathione, and the thiol transport. A similar impairment of glutathione metabolism was observed in K562 cells with high glucose levels. The cytotoxicity by a xenobiotic (1-chloro-2,4-dinitrobenzene) was higher in K562 cells with high glucose than in control subjects (50% of inhibitory concentration. 300±24 mol/l vs 840±29 mol/l, p<0.01). Expression of -glutamylcysteine synthetase protein was augmented in K562 cells with high glucose, while enzymatic activity and expression of mRNA were lower than those in the control subjects. These results suggest that inactivation of glutathione synthesis and thiol transport in diabetic patients increases the sensitivity of the cells to oxidative stresses, and these changes may lead to the development of some complications in diabetes mellitus.Abbreviations ATP Adenosine 5-triphosphate - NIDDM non-insulin-dependent diabetes mellitus - GSH -glutamylcysteinyl glycine - GSSG glutathione disulphide - -GCS -glutamylcysteine synthetase - mRNA messenger ribonucleic acid - DNA deoxyribonucleic acid - C₅₀ 50% inhibitory concentration - CDNB 1-chloro-2,4-dinitrobenzene - GS-DNP S-(2,4-dinitrophenyl)glutathione - PSL photostimulated luminescence     

Presence of Two Signaling TGF-β Receptors in Human Pancreatic Cancer Correlates with Advanced Tumor Stage

Transforming growth factor- (TGF-)signal transduction is mediated via specific cellsurface signaling TGF- receptors, most notably thetype I ALK5 (TR-I_ALK5)and the type II(TR-II). We evaluated TR-I_ALK5 andTR-II expression in 41 human pancreatic cancertissue samples and correlated these findings withclinical data of the patients. Northern blot analysisindicated that, in comparison with the normal pancreas,pancreatic adenocarcinomas exhibited 8.0-fold and4.5-fold increases (P < 0.01), respectively, in mRNAlevels encoding TR-I_ALK5 andTR-II. In situ hybridization showed that both TR-I_ALK5 mRNAwere highly expressed in the majority of pancreaticcancer cells. Immunohistochemical analysis ofTR-I_ALK5 and TR-II revealedpositive immunostaining in 73% and 56% of the tumors, respectively. Both receptorswere concomitantly present in 54% of the pancreaticcancer samples. The presence ofTR-I_ALK5 or TR-II and theconcomitant presence of TR-I_ALK5 and TR-II in the cancer cells was associatedwith advanced tumor stage (P < 0.01). These findingsshow that in many human pancreatic cancers, increasedlevels of the two signaling TRs are present. The presence of the signaling TRs inadvanced tumor stages indicates a role in diseaseprogression.     

Der Patient als Keimquelle in der Intensivpflegestation

Zusammenfassung 133 Patienten einer Intensivpflegestation, die bei der Aufnahme keine Symptome bakterieller Infektion zeigten und noch keine Antibiotika erhalten hatten, wurden nach dem Zufallsprinzip zwei Gruppen zugeordnet. Eine Gruppe (+Pat.) erhielt eine Antibiotikaprophylaxe mit Penicillinen oder Cephalosporinen, die zweite Gruppe (–Pat.) erhielt keine Antibiotika. Staph. aureus war bei –Pat. im Trachealsekret und in der Umgebung der häufigste potentiell pathogene Keim. Staph. aureus war im Trachealsekret und in der Umgebung der –Pat. signifikant häufiger als bei +Pat.. Klebsiella spp. standen im Trachealsekret und in der Umgebung von +Pat. an erster Stelle. Sie waren im Trachealsekret von +Pat. signifikant häufiger als bei –Pat.. In der ersten Woche des Stationsaufenthaltes traten bei +Pat. starke Veränderungen in der Keimflora der Trachealsekrete auf: die Besiedelung mit gramnegativen Keimen stieg auf fast 100% an, gleichzeitig ging die Frequenz von Staph. aureus zurück. In den Abklatschuntersuchungen aus der Patientenumgebung traten gramnegative Stäbchen bei +Pat. in signifikant höheren Koloniezahlen auf als bei –Pat.. Die paarweisen Vergleiche von Bakterienstämmen aus den Trachealsekreten und aus der Patientenumgebung ergaben, daß +Pat. gramnegative Keime und –Pat. Staph. aureus signifikant häufiger an die Umgebung abgaben. Auf die Kontamination der Patientenumgebung mit Staph. aureus wirkte sich der Faktor der trachealen Intubation nicht aus. Gramnegative Keime waren im Trachealsekret von intubierten Patienten signifikant häufiger als bei nicht intubierten. Derselbe Trend zeigte sich auch in der Patientenumgebung. Die Antibiotikaprophylaxe konnte, wie die klinischen Ergebnisse der Studie zeigten, die Patienten nicht im erwarteten Ausmaß vor Infektionen schützen. Patienten, insbesondere tracheal-intubierte, die Antibiotika erhalten, sind als Streuquellen für hochresistente gramnegative Keime anzusehen.

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The patient as a source of bacteria in intensive care units: Influence of antibiotics and tracheal intubation

Summary 133 patients in an intensive care unit, who prior to admission had not shown any signs of bacterial infection and had not received antibiotic treatment, were assigned to two groups at random. One group received antibiotic prophylaxis with penicillins or cephalosporins (+Pat.), the other group did not receive antibiotics (–Pat.). Staph. aureus was the most frequent facultative pathogen in tracheal secretions and in the environment of –Pat.. This organism was significantly more frequent in –Pat. than in +Pat. in both the tracheal secretions and the enviroment. Klebsiella spp. outnumbered all other species in +Pat.. They were significantly more frequent in tracheal secretions of +Pat. than of –Pat.. In the first week of hospitalisation marked changes were seen in bacterial flora of tracheal secretions of +Pat.. Colonization with gramnegative bacteria rose to nearly 100%, the frequency of Staph. aureus diminishing at the same time. Monitoring by contact cultures revealed that gramnegative rods were significantly more numerous in the environment of +Pat. than of –Pat.. Matching bacterial strains cultured from tracheal secretions and from the environment of the patients proved that +Pat. spread significantly higher numbers of their gramnegative bacteria into the environment. The same is true of –Pat. for Staph. aureus. Intubation had no noticeable effect on the degree of contamination of the surroundings with Staph. aureus. Gramnegative rods were significantly more frequent in tracheal secretions of patients with intubation than in patients without. The same trend was observed for environmental contamination. As the clinical results of this study have shown, antibiotic prophylaxis does not protect patients from infections to the extent expected. Patients, and particularly intubated patients, receiving antibiotic treatment have to be considered as sources of highly resistant gramnegative organisms.

     

Compound heterozygosity for a β∘-thalassemia (frameshift codons 38/39; -C) and a nondeletional swiss type of HPFH (A→C at NT -110, Gγ) in a Czechoslovakian family

Summary We have analyzed the levels and composition of the fetal hemoglobin (Hb F) in several members of a Czechoslovakian family with a heterozygosity for a newly discovered -thalassemia (codons 38/39; -C), or for a newly detected nondeletional hereditary persistence of fetal hemoglobin (a form of Swiss-HPFH with an AC mutation at nucleotide –100 5 to the Cap site of G), or with a compound heterozygosity for these two conditions. The Hb F level in the -thalassemia heterozygotes averaged 0.3% with low G values ( 28%) and relatively high AT values ( 50%), that in the two Swiss-HPFH heterozygotes averaged 0.8% with 95% G, while that of the compound heterozygote was 3.1% with 95% G. The low Hb F levels were determined with a recently published cation exchange high-performance liquid chromatography (HPLC) procedure that is accurate at the 0.1%–0.2% Hb F level [3]. This method, together with a reversed-phase HPLC procedure, made it possible to detect this unusual type of nondeletional G-HPFH and provided the data indicating that the increased Hb F in the compound heterozygote was derived mainly from the chromosome with the HPFH determinant.This study was supported in part by USPHS Research Grant HLB-41544     

Efficacy and Tolerability of the Long-Acting Somatostatin Analog Lanreotide in Acromegaly. A 12-Month Multicenter Study of 58 Acromegalic Patients

Objective: To determine the effects of the new somatostatin analogue, lanreotide, in its prolonged released form (PR), in patients with acromegaly.Design: Prospective open multicenter non comparative study.Setting: Thirty-three university-affiliated medical centers.Patients: One hundred sixteen acromegalic patients with active disease, of whom 58 patients complied with the protocol and completed the 12-month period treatment.Intervention: Lanreotide PR treatment was started at a dose of 30 mg intramuscularly every 14 days. If integrated mean plasma GH levels were not below 5 g/L and/or IGF-I levels were not normalized after one month of treatment, injections were given every 10 days. The duration of the study was 12 months.Results: After one month of treatment mean plasma GH and IGF-I levels had fallen from 10.7 ± 11.1 g/L (mean ± SD; range, 2.6 – 74.8 g/L; median, 7 g/L) and 718 ± 270 g/L (range 338 – 1440 g/L; median, 645 g/L), respectively, to 7.8 ± 10.1 g/L and 575 ± 252 g/L, respectively. Thirty patients (22%) had plasma GH levels below 2.5 g/L, and 8 patients (16%) had age-adjusted normal plasma IGF-I levels. At the sixth month of treatment mean plasma GH levels of 2.5 g/L or less, and normal plasma IGF-I levels were observed in 33%, and 33% of patients, respectively. At the twelvth month of treatment, these percentages were 41%, and 41%, respectively. The interval between two injections was shortened (one injection every 10 days) in 8 of the 58 patients (13%) at the second month of treatment, and at the end of the study, 70% of patients required 3 injections per month. The most frequent adverse event elicited by enquiry was transient diarrhea (76% of patients), followed by abdominal pain (62%) and pain at the injection site (59%). Based on the analysis of a subgroup of 46 patients who had at least a measurement of fecal fat content after day 0 of the study, a non significant increase (from 4.2 ± 3.4 to 5.1 ± 4.3 g/24h, p = 0.3) in mean steatorrhea was observed during treatment. Before treatment, steatorrhea was present in 9 (19%) patients. During the study, 15 additional patients (32%) developed persistent steatorrhea, and there was a transient increase in fecal fat content above 6 g/24 h in another 11 patients. After exclusion of the 7 patients (12%) with gallstones at enrolment, new gallstones were diagnosed in 6 out of 50 patients (12%) during the study.Conclusion: Two or three monthly injections of lanreotide PR decreased GH concentration to less than 2.5 g/L and normalized IGF-I levels in 41% of patients treated during 12 months. The good tolerability of this treatment, and the reduction in the frequency of injections, plus the sustained drug serum concentrations, confirm the usefulness of this new somatostatin analog formulation.     

Comparison Between Ischaemic and Anisomycin-Induced Preconditioning: Role of p38 MAPK

To further evaluate the significance of p38 MAPK as trigger or mediator in ischaemic preconditioning, anisomycin and SB 203580 were used to manipulate its activation status. Special attention was given to the concentration of the drugs and protocols used.The isolated perfused rat heart, subjected to either 25 min global ischaemia or 35 min regional ischaemia, was used as experimental model. This was preceded by anisomycin (2 or 5 M: 3 × 5 min; 5 M: 5 min or 10 min; 5 M: 10 min + 10 min washout or 20 M: 20 min) or SB 203580 (2 M: 3 × 5 min; before and during 3 × 5 min or 1 × 5 min ischaemic preconditioning; 10 min). Endpoints were functional recovery during reperfusion and infarct size.Anisomycin, regardless of the protocol, reduced infarct size, but did not improve functional recovery. In a number of experiments activation of JNK by anisomycin was blocked by SP 600125 (10 M). SP 600125 had no effect on the anisomycin-induced reduction in infarct size. SB 203580 when administered for 10 min before sustained ischaemia, improved functional recovery and reduced infarct size. SB 203580 could not abolish the beneficial effects of a multi-cycle preconditioning protocol, but it significantly reduced the outcome of 1 × 5 min preconditioning. In all hearts improved functional recovery and reduction in infarct size were associated with attenuation of p38 MAPK activation during sustained ischaemia-reperfusion.The results indicate that activation of p38 MAPK acts as a trigger of preconditioning, while attenuation of its activation is a prerequisite for improved recovery and a reduction in infarct size.     

Comparative and combined effects of transforming growth factors α and β, interleukin-1 and interferon-γ on rheumatoid synovial cell proliferation,glycolysis and prostaglandin E production

Summary Enhanced cell proliferation, glycolysis and prostaglandin E production are all characteristic features of rheumatoid synovial tissue. The interrelationships of these three cellular parameters have been examined using rheumatoid synovial fibroblasts and their responses to specific cytokines in vitro. Transforming growth factor (TGF) caused a more than threefold increase in synovial cell proliferation whilst transforming growth factor (TGF), interleukin-1 (IL-1) and interferon- (IFN-) produced only marginal changes. The combined addition of IL-1 with TGF resulted in an enhanced proliferative response comparable with that produced by TGF. Glycolysis, estimated by glucose utilisation and measurements of the glycolytic regulatory metabolite fructose 2,6-bisphosphate was significantly stimulated by TGF, IL-1 and IFN-, but less so by TGF. Prostaglandin E production was significantly increased by IL-1 to an extent much greater than that produced by TGF or TGF, although the combined addition of IL-1 with either TGF or resulted in a synergistic increase in PGE production, a response partly diminished by the addition of IFN-. These findings suggest that the extent to which a cytokine stimulates glycolysis is not consistently related to its mitogenicity, and that cytokine combinations which stimulate high levels of PGE production (a growth inhibitor) will not necessarily be associated with a reduced rate of cellular proliferation in cultured, adherent, rheumatoid synovial fibroblasts.     

Immunoglobulin characterization of human pancreatic fluid

Human pancreatic fluid obtained from 2 subjects, each with a traumatic pancreatic fistula, contained detectable levels of IgG, IgA, IgM, IgD, and IgE. Although the mean IgG/IgA ratio for 10 random specimens was 1.63, the relative concentration was estimated to be less than unity when extreme values were eliminated. The molecular weight of IgA in pancreatic fluid was found to be comparable to that of the IgA molecule in serum. The absence of secretory component in pancreatic IgA provides further evidence that pancreatic IgA and serum IgA are similar. Serial determinations of the immunoglobulins stored at 4° C showed a progressive decrease of all immunoglobulins, the order of stability being IgGIgA>IgMIgD. The demonstrated proteolytic activity in the specimens could account for the immunoglobulin decay and for the variable detection of IgM and IgD in pancreatic-fluid specimens.     

Macrophages enhance binding of beta-VLDL and cholesterol ester accumulation in cultured aortic smooth muscle cells

Summary The effect of macrophages on the uptake of -very low-density lipoprotein (-VLDL) by smooth muscle cells (SMC) expressing different morphological phenotypes was examined in culture. The SMC were grown alone and in co-culture with macrophages for four days, then incubated with different concentrations of¹²⁵I--VLDL for 3 h at 4°C or with 75 ug/ml -VLDL for 24h at 37°C. The binding of -VLDL to SMC at 4°C was enhanced in the presence of macrophages irrespective of the phenotype expressed by SMC. This occurred through modification of the lipoprotein, since binding of re-isolated macrophage-conditioned -VLDL to SMC was 12.5 times that of fresh -VLDL. This modified form of -VLDL competed with fresh -VLDL for binding to SMC. Binding was inhibited in the presence of probucol, suggesting that an oxidative mechanism may be involved.The presence of macrophages also enhanced the accumulation of -VLDL-derived cholesterol in SMC. While most of this is a consequence of the enhanced binding, macrophages may also act directly on SMC to increase cholesterol accumulation, since the activity of acid cholesterol ester hydrolase and neutral cholesterol ester hydrolase in SMC was reduced in the presence of macrophages.     

γ/δ Receptor-expressing T-cell clones from a cutaneous T-cell lymphoma suppress hematopoiesis

Summary Recently we described a cutaneous T-cell lymphoma expressing the / T-cell receptor [5]. The patient suffering from this lymphoma showed low numbers of myeloid and T cells in peripheral blood, while B and NK cells were relatively increased. In vitro culture of the patient's bone marrow (BM) cells revealed a significant suppression of myeloid/monocyte colony formation (GM-CFU) compared with normal controls. This was not due to infiltration of the BM with lymphoma cells. We speculated that a soluble factor either secreted or induced by the lymphoma cells might be responsible for the marked suppression of hematopoiesis in this patient. From a skin biopsy with infiltrating / T-lymphoma cells we established T-cell clones bearing the / T-cell receptor and resembling the phenotype of the lymphoma cells. The supernatant (SN) of these / T-cell clones reduced the number of colonies in a CFU-GM assay (using normal control BM) in comparison to SN of / T-cell clones established from the same biopsy. This suppression was seen mainly on day 7 of culture and was not neutralized by the addition of placenta-CM. The main mediator of this suppression seems to be IFN-,since it was detectable in high amounts in the SN of these / T-cell tumor clones as well as in the serum of the patient. In addition, anti-IFN- antibodies can reverse the T-cell SN-mediated suppression of CFU-GM. We conclude that high serum levels of interferon-, which is secreted in high amounts from / T-cells grown from a biopsy of a cutaneous lymphoma, can suppress hematopoiesis.Abbreviations TCR T-cell receptor - IFN- interferon- - SN supernatant - placenta CM placenta conditioned medium - BM bone marrow - CFU-GM myeloid/monocyte colony formation - NK cells natural killer cells - Ab antibody M. Wilhelm was supported by theDeutsche Forschungsgemeinschaft (DFG Wi 728-2)     

Modulation of pacemaker activity in sheep cardiac Purkinje fibers by stimulation of β-adrenoceptor subtypes

The electrophysiological effects mediated by ₁- and ₂- in spontaneously active sheep cardiac Purkinje fibers were investigated using the non-selective agonist (–)-isoproterenol (IPN) and the selective agonists (–)-noradrenaline (₁) and procaterol (₂) in the absence and presence of the selective antagonists bisoprolol (₁) and ICI 118,551 (₂).IPN (0.01 mol/l) increased the spontaneous rate by 54% and the slope of diastolic depolarization by 68% of the respective control values. Further, IPN increased the action potential duration at –20 mV (APD –20 mV) from 96 to 154 ms, reduced the APD –70 mV by 17% and the duration of the diastole by 39% and slightly hyperpolarized the maximum diastolic potential. These effects were partially inhibited by ICI 118,551 (0.03 mol/l), diminished by bisoprolol (0.1 mol/l) and almost completely blocked by the combination of both antagonists. Concentration response curves of IPN were influenced by the selective antagonists as follows: ICI 118,551 (0.03 mol/l) shifted the curves to the right by 0.2–0.4 log units and increased the slope factor. Bisoprolol (0.1 mol/l) induced a greater shift to the right by 1.1–1.5 log units. Combination of bisoprolol with ICI 118,551 shifted the curves to the right by 1.5–1.7 log units.Noradrenaline (0.3 mol/l) elicited similar actions as IPN. Bisoprolol (0.1 mol/l) shifted the concentration response curves of noradrenaline to the right by 1.1–1.9 log units. Actions of procaterol (0.1 mol/l) were weak, attained only 15–35% of the maximal effects of IPN and could be blocked by ICI 118,551 (0.03 mol/l).These results show that the increase of pacemaker activity induced by catecholamines in sheep cardiac Purkinje fibers is predominantly mediated by stimulation of ₁. However, contribution of ₂ mediated effects could be demonstrated.Supported by Ministerium für Wissenschaft und Forschung, Nordrhein-Westfalen, Projekt-Nr, 40008786.     

Estrogen receptor beta (ERβ) is expressed in brain astrocytic tumors and declines with dedifferentiation of the neoplasm

Purpose Estrogen receptor (ER) is the second identified receptor mediating the effects of estrogen on target tissues. The role of ER in cancer pathobiology is largely unknown, because specific antibodies have not been available until recently. Initial studies have shown that ER expression declines in breast, ovarian, prostatic, and colon carcinomas. Tamoxifen, a synthetic anti-estrogen compound that is a mixed agonist/antagonist of estrogen receptor (ER) and a pure antagonist of ER, has moderate beneficial effects in human astrocytic neoplasms. However, most published studies agree that glial tumors do not express ER. The purpose of this study was to explore the expression of ER in astrocytic neoplasms.Methods ER expression was monitored immunohistochemically in 56 cases of astrocytomas of all grades (grade I–IV) and in adjacent non-neoplastic brain tissue.Results Moderate or strong nuclear immunopositivity was obtained in non-neoplastic astrocytes and in low-grade astrocytomas, whereas the majority of high-grade tumors were immunonegative or displayed weak immunoreactivity. The progressive decline in ER expression paralleled the increase in tumor grade.Conclusions In as much as ER is possibly the only ER expressed in astrocytes, its decreased expression may play an important role in astrocytic tumor initiation and in the potential response of glial neoplasms to tamoxifen.     

Morphine and Gastroduodenal Motility

This study investigated the effects ofintravenous morphine on gastric antral and duodenalmotility in healthy volunteers. Intravenous morphine(both infusion and bolus) increased duodenal motility,typically as bursts of contractions similar to phase IIIof the migrating motor complex. Intravenous infusion ofmorphine 40 g/kg/hr rapidly increased duodenalmotility in nine of 10 subjects; in eight it was phase III-like. Intravenous infusion ofnaloxone (40 g/kg/hr) blocked this effect ofmorphine infusion in five of six subjects. Morphinebolus injection (5-20 g/kg) in six subjects (30-42min following a spontaneous phase III) induced furtherduodenal phase III-like activity; also, morphine bolusinjection (5-20 g/kg) in five subjects (30-42 minfollowing a liquid meal) induced duodenal phase III-like activity. Atropine (10 g/kg intravenously)was able to prevent the action of morphine (bothintravenous infusion and intravenous bolus injection) ininducing this phase III-like activity. Theseobservations show: (1) morphine in very low dose is able tostimulate maximal duodenal contractility; (2) themotility response is typically phase III-like; and (3)morphine acts on opioid receptors to initiate this phase III-like activity, with the effectblocked by antimuscarinic drugs.     

Antiproliferative effects of interferonγ in combination withα-difluoromethylornithine on human carcinoma cell cultures

The antiproliferative effects of human recombinant interferon (IFN) in combination with -difluoromethylornithine (DFMO) or as single agents were assessed on human cell cultures derived from carcinomas of the breast (MCF-7), the ovary (EFO-27) or the kidneys (EGI-4). Results were obtained in proliferation assays by direct cell counting. The cell lines differed considerably in their sensitivities to the antiproliferative effect of IFN as compared by the 50% inhibition doses of the growth (ID₅₀). In contrast to the findings with IFN, similar antiproliferative effects resulted from the application of comparable doses of DFMO. While IFN induced cytotoxic effects in EGI-4 cells, DFMO produced only cytostatic actions in the cell lines analyzed. Synergistic growth inhibition resulted from the combined application of IFN and DFMO in EFO-27 cell cultures. This finding was most pronounced after treatment with IFN or DFMO doses below the respective ID₅₀ values. However, antagonistic effects occurred in cells of the line EGI-4 after DFMO had been combined with IFN at concentrations below the cytotoxic dose range. Within the sensitivity of our proliferation assay, no synergistic interactions were found in MCF-7 cell cultures. In the cell lines tested, no relation between the sensitivity for the single agents and the effectivity of the drug combination was identified. Despite promising synergistic effects in the moderately IFN-sensitive ovarian carcinoma cell line EFO-27, the efficacy of the IFN/DFMO combination was restrained by possible antagonistic effects as demonstrated in the highly IFN-sensitive EGI-4 renal carcinoma cell cultures. We conclude that the differential interaction patterns in the cell cultures analyzed preclude general suggestions for clinical studies using IFN and DFMO.Abbreviations IFN interferon - DFMO difluoromethylornithine This work was part of the doctoral thesis of Mariam Klouche