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R Neuhaus

Publications and source records attributed to R Neuhaus.

At least 91 records · Page 5Linked to original sources
PubMed1995

Flow cytometric analyses of the subclasses of red cell IgG antibodies.

We report on flow cytometric IgG subclass determinations of red cell antibodies using polyclonal FITC-labeled antibodies. The limit of detection of this method was 1 ng anti-D per 1 x 10(7) red cells. The inter- and intra-assay coefficients of variance were 8.2 and 2.3%, respectively. In 8 newborns with a positive direct antiglobulin test (DAT) in the gel centrifugation test (GCT), due to ABO antibodies, IgG1 was detected in all and IgG2 additionally in 4 of these cases. In 5 severe cases of hemolytic disease of the newborn (HDN) due to anti-D, large amounts of IgG1 were found, and in 3 of these 5, IgG3 in combination with IgG1. In 8 mild or moderate HDN cases (4 anti-D, 2 anti-E, 1 anti-Fya, 1 anti-Jka), phototherapy sufficed, and IgG1 was the only antibody. In 7 adult patients with malignant lymphoma and a positive DAT (GCT), only small amounts of IgG1 red cell autoantibodies could be demonstrated by flow cytometry. In 5 further patients with malignant lymphoma, a positive DAT, and severe hemolytic anemia, large amounts of IgG1 autoantibodies were found and IgG3 was also present in 3 of these cases. Flow-cytometric determination of IgG subclasses may be a useful tool in immunohematology, since subclass determinations were possible in all of these cases. This method is suited for clinical routine and offers the possibility of sufficient standardization.

Adult↗
PubMed1994

Long-term follow-up of hepatitis B virus-infected recipients after orthotopic liver transplantation.

The outcome after OLT was studied in 53 patients with chronic hepatitis B virus (HBV)* infection, 15 of whom had, in addition, evidence of hepatitis delta virus (HDV) superinfection. Nine of 53 patients received short-term immunoprophylaxis with anti-hepatitis B surface (HBs) hyperimmunoglobulin up to 1 week after OLT and 44 of 53 patients received long-term unlimited immunoprophylaxis. Eight of 9 (89%) patients with short-term immunoprophylaxis showed reactivation of replication with HBV DNA in serum > 10 pg/ml independently of the preoperative HBV DNA level and HBsAg reappeared in all cases. Four (44%) patients in this group lost their graft because of fulminant hepatitis or cirrhosis and required retransplantation, and 2 patients (22%) died after reinfection in the second graft. Nineteen of 44 (43%) patients with long-term immunoprophylaxis developed HBV values > 10 pg/ml after transplant and 12 of 44 (27%) became HBsAg+ again. Most of them had quantifiable HBV DNA levels before OLT. Retransplantation was required in 5 of 44 (11%) patients and 4 of them died after HBV recurrence. The frequency of HBV reactivation and the development of viral hepatitis after OLT were associated with the preoperative presence of HBV, as determined by the molecular hybridization assay. With nested polymerase chain reaction, all 53 patients were HBV-DNA+ in the serum before and after OLT. with just one exception, none of the patients with HDV superinfection died, in spite of increased HDV replication after OLT. The data indicate that long-term immunoprophylaxis with anti-HBs hyperimmunoglobulin after OLT improves the prognosis in HBV-infected patients. The preoperative detection of HBV DNA in serum by molecular hybridization assay is correlated with graft infection and represents a prognostic parameter. The presence of HDV may have a protective effect after OLT.

Adult↗
PubMed1994

[Flow cytometry analysis of IGG subclasses of auto- and alloantibodies in autoimmune hemolytic anemia and hemolytic disease of the newborn].

Red cell IgG antibodies capable of causing hemolytic disease of the newborn (HDN) or autoimmune hemolytic anemia (AIHA) have been analyzed concerning their IgG subclasses using flow cytometry. The results were always in agreement with those of the direct Coombs test. Anti-A and/or anti-B able to cause HDN belonged to the IgG1 subclass (4/8 cases) or to the subclasses IgG1 and IgG2 (4/8 cases). In 3 out of 4 cases of HDN caused by Rh antibodies the antibodies belonged to the subclasses IgG1 and IgG3. In patients with lymphoma but without AIHA, red cell autoantibodies were often found to be IgG1 only (n = 10), in low concentrations. In cases of acute AIHA in adults caused by IgG autoantibodies the subclass IgG3 was found in addition to IgG1 in 4/5 cases. In our opinion flow cytometry should become substantial for immunohematological diagnostics.

Adult↗
PubMed1993

Quality of life of liver transplant recipients. A pilot study.

In a cross-sectional survey of the quality of life of 45 liver transplant recipients, physical and psychological status, physical complaints, capability to participate in daily life, social support, and global quality of life were assessed. The average time of follow-up was 9 months after transplantation. Nine patients had moderate liver damage, 12 suffered from drug side effects, and 10 had extrahepatic diseases. Physical complaints, especially rheumatism, exhaustion, and gastric complaints, were higher than in the general population. Most patients were able to participate in daily life (do housework, take part in family life, etc.). Apart from the complex "health" (use of body), they did not differ in this respect from healthy individuals. Eighty percent of the patients reported having very good social support. The psychological status was generally good, with only 5% complaining of anxiety and nervousness. Sixty percent regarded their quality of life to be very high, 31% reported medium quality of life, and 9% felt very bad. No relationship was found between low quality of life and transplant malfunction; patients with extrahepatic diseases had the lowest quality of life. Among all subgroups, the individuals who were actively working again felt best. Psychological qualities necessary for coping with daily life (self-assurance, self-realization, satisfaction, and happiness) correlated most with the global quality of life (r = 0.80), whereas no relationship was found between quality of life and complaints in total (r = -0.32). This survey shows that during the first year after transplantation, transplant recipients report a high quality of life in important areas of living, despite many physical complaints, and even display an almost euphoric mood.

Adult↗
PubMed1993

[Changes in cervix cytology in women with liver transplants treated with immunosuppressive therapy].

During the time 1989 to 1992 we collected PAP smears of 58 women before and several times after a liver transplantation. Five of the patients (= 8.6%) showed a suspicious PAP smear, although pre-transplantation they had a normal cervical cytology. Histological one woman even had a higher grade dysplasia. 30 women received FK 506 after the liver transplantation, 28 patients Cyclosporin A as long-term medication. Likewise kidney and liver transplanted women have a higher risk to be affected by a cervical neoplasia. A acceleration of malignant growth seems to be likely. The influence on the cervical cells of both immunosuppressive drugs Cyclosporin A (Sandimmun) and FK 506 seem to be similar. It should be recommended to perform a close-meshed cervical cytology control when following -up the female liver transplant recipients.

Adolescent↗
PubMed1993

[Single coronary artery with branching of the right coronary artery from the left atrioventricular ramus of the circumflex artery. Incidence and significance].

In a series of 8500 consecutive coronary angiographies, we found three times an "anatomic single coronary artery" with origin of the right coronary artery from the AV-branch of the dominant circumflex artery (incidence 0.035%). In all three patients the investigation was made because of the suspicion of coronary heart disease. All 59 previously published cases (44 found at coronary angiography, 15 at necropsy) and our own three cases were not associated with other cardiovascular anomalies. A pathophysiological significance of this anomaly alone with regard to inducing myocardial ischemia can almost be excluded. The knowledge of this anomaly however is important to avoid errors in diagnosis and to evaluate the exact degree of severity of coronary heart disease.

Aged↗
PubMed1992

Inhibition of protein kinases in rat pheochromocytoma (PC12) cells promotes morphological differentiation and down-regulates ion channel expression.

We have studied morphological differentiation and ion channel expression in PC12 cells under different culture conditions. Differentiation mediated by nerve growth factor (NGF) was compared with that induced by depletion and inhibition of protein kinases (phorbol ester beta-PMA plus staurosporine). Morphological differentiation was similar under both conditions. However, ion channel densities, studied by means of the patch-clamp technique, were enhanced by NGF and reduced by beta-PMA+staurosporine. Similar changes were also observed for omega-conotoxin-sensitive Ca2+ channels by measuring radioligand binding. The decrease in Ca2+ channel density, after treatment of the cells with beta-PMA+staurosporine, resulted in a reduced increase in the intracellular Ca2+ concentration during K+ depolarization. We conclude that morphological differentiation, but not ion channel expression, can occur during depression of protein kinase activities in PC12 cells.

Alkaloids↗
PubMed1992

Inhibition of membrane currents and rises of intracellular Ca2+ in PC12 cells by CGS 9343B, a calmodulin inhibitor.

The calmodulin inhibitor 1,3-dihydro-1-[1-((4-methyl-4H,6H-pyrrolo[1,2-a]-[4,1]benzoxazepin - 4-yl)methyl)-4-piperidinyl]-2H-benzimidazol-2-one maleate (CGS 9343B) caused a reversible block of voltage-activated Ca2+, Na+, and K+ currents in differentiated rat pheochromocytoma (PC12) cells. The drug also inhibited nicotinic acetylcholine receptor (nAChR) channel currents but not inward currents evoked by extracellular ATP. Depolarization-induced intracellular Ca2+ transients were almost completely inhibited in growth cones and cell bodies by CGS 9343B. Our results suggest actions of CGS 9343B on ion fluxes unrelated to calmodulin inhibition.

Adenosine Triphosphate↗
PubMed1992

Hepatitis C virus reinfection in allografts after orthotopic liver transplantation.

From September 1988 to May 1991, 160 orthotopic liver transplantations were performed in our hospital. Twenty-four patients had end-stage cirrhosis caused by chronic non-A, non-B hepatitis. Antibodies against hepatitis C virus were documented before and after orthotopic liver transplantation in 13 patients. Studies using the polymerase chain reaction demonstrated hepatitis C virus RNA in the serum and liver tissue of 17 patients (10 of whom tested positive for hepatitis C virus antibodies) before orthotopic liver transplantation. Tissue samples taken from liver grafts during the operation were hepatitis C virus RNA negative in every case. Ten of these 17 patients had positive hepatitis C virus RNA findings in serum and liver biopsy specimens within the first month after surgery. One patient died of Mucor sepsis 2 mo after orthotopic liver transplantation. Another patient died of multi-organ failure 3 mo after a retransplantation. Two patients underwent retransplantation for graft rejection at 2 and 3 mo, respectively. One year after orthotopic liver transplantation, hepatitis C virus RNA was demonstrated in allograft biopsy specimens in 13 of 15 patients. Two patients remained hepatitis C virus RNA negative in repeated biopsies up to 12 mo. Mild portal and lobular hepatitis developed within 6 months of orthotopic liver transplantation in four patients and within 1 yr in five additional patients. The data suggest that persistent hepatitis C virus reinfects the allograft in most cases, but the risk of acute organ damage caused by hepatitis C virus reinfection is low.

Adult↗
PubMed1992

Activation of different pathways for calcium elevation by bradykinin and ATP in rat pheochromocytoma (PC 12) cells.

We have studied the pathways by which extracellular bradykinin and adenosine 5'-triphosphate (ATP) elicit changes in intracellular free calcium ([Ca2+]i) in nerve-growth-factor(NGF)- treated rat pheochromocytoma (PC 12) cells. Both substances caused a significant rise in [Ca2+]i as assessed by fura-2 based microfluorimetry. The bradykinin-induced response consisted of an initial Ca2+ mobilization from an internal pool followed by a sustained increase in [Ca2+]i, which was due to activation of a small inward current. The initial response always started at a localized site opposite to the cell nucleus. The inward current was partially carried by Ca2+ and began with a time lag of about 4 s after the start of the initial transient signal. Stepwise hyperpolarization of the plasma membrane, after activation of the inward current by bradykinin, caused a simultaneous increase in current amplitude and in [Ca2+]i, due to an increase in the driving force for Ca2+ influx. With ATP as an agonist the onset of inward current coincided with an increase in [Ca2+]i. Inward current and [Ca2+]i were enhanced during hyperpolarizing steps indicating a substantial Ca2+ influx through ATP-activated channels. No release of Ca2+ from internal stores, but a large Na+ inward current, was observed in Ca(2+)-free external solution after addition of ATP. While the bradykinin-induced responses were much more pronounced in cell bodies than in growth cones, the ATP effects were somewhat variable in cell bodies and more homogeneous in growth cones.

Adenosine Triphosphate↗
PubMed1992

[Orthotopic liver transplantation in hepatic cirrhosis: on the problem of infection of the transplant with persistent hepatitis viruses].

269 orthotopic liver transplantations (OLT) were performed in 253 patients at our institution from September 1988 to May 1992. 121 patients had end-stage cirrhosis secondary to viral hepatitis type B, delta, or type non-A non-B and C respectively. Reinfection of the graft by persistent viruses is a potential complication in these cases. Passive immunization with anti-HBs hyperimmunoglobulin (HIg) can prevent clinically relevant reinfection of the graft in patients with hepatitis B virus (HBV) infection and low replication rates. Patients with high replication rates will rarely benefit from OLT. Patients with hepatitis delta virus (HDV) infection usually experience HDV reinfection of the graft with subsequent chronic hepatitis although prophylaxis with anti-HBs-HIg was performed. Treatment with interferon alpha had no apparent effect on the incidence of graft reinfection with HBV in this series, but the replication rate of HDV was reduced. Persistent hepatitis C viruses (HCV) usually infect the graft; this was demonstrated in 17 patients by means of the polymerase chain reaction. HCV infection usually causes a mild form of acute hepatitis with transition to a chronic course. Therefore the significance of persistent viral infection lies in the potential for chronic hepatitis in the transplanted organ rather than in the danger of acute injury of the allograft.

Biopsy, Needle↗