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W Gerlich

Publications and source records attributed to W Gerlich.

At least 19 recordsLinked to original sources
PubMed1996

[Trends in autologous blood transfusion in the old states of the Federal Republic of Germany, 1989-1993. 1. A panel study of 143 hopitals].

Increased perception of the risks of homologous blood transfusion has focused substantial interest on autologous blood transfusion (ABT). To evaluate the role of ABT in the Federal Republic of Germany (FRG), we conducted postal surveys of German hospitals in 1989 and 1993. In the present study, the responses of 143 hospitals in the "old" federal states (former West Germany) that replied to both of our surveys were analysed. The objective was to examine trends in ABT practice in the FRG from 1989 to 1993. The study was restricted to the "old" federal states because data for the "new" federal states (former German Democratic Republic) were not available for that period. METHODS. Data presented in this study were obtained by postal surveys of German hospitals in 1989 and 1993. Because of German reunification (3 October 1990), only hospitals in the "old" federal states were surveyed in 1989, while hospitals in both the "old" and "new" states were included in 1993. Four hundred randomly selected hospitals in the "old" federal states were included in both surveys, 143 of which responded to both. The completed questionnaires of these 143 hospitals were analysed. In addition, to estimate the magnitude of positive selection bias, the data provided by these 143 hospitals were compared with data provided by another set of 162 hospitals in the "old" federal states that replied to the 1993 but not to the 1989 survey. RESULTS. There were no significant changes from 1989 to 1993 in the 143 hospitals with respect to hospital size by number of beds and spectrum of surgical specialties. The proportion of hospitals that performed preoperative autologous blood donation grew by 20% (from 74% to 89%) and the proportion that used this technique regularly ("frequently" and "mostly") rose by 80% (from 25% to 45%). The percentage of hospitals that performed preoperative plasmapheresis had more than doubled (from 8% to 19%). The proportion that used acute isovolaemic haemodilution grew by 32% (from 62% to 82%), while those doing so regularly ("frequently" and "mostly") increased by only 17% (from 23% to 27%). The fraction of hospitals equipped with cell-washing devices grew by 29% (from 35% to 45%). General transfusion practice, as measured by acceptance of postoperative haemoglobin levels of less than 10.0 g/dl, had changed but little. CONCLUSIONS. Although the 143 hospitals are not representative on a national level, the findings of our study allow some conclusions on general trends in the "old" states of the FRG. The potential for ABT has substantially grown in the "old" states from 1989 to 1993, although more consistent advantage of this potential could be taken.

Blood Transfusion, Autologous↗
PubMed1996

[Autologous blood transfusion in the Federal Republic of Germany--results of a questionnaire in 1993. 2. The use of autologous transfusion in the old and new federation].

In 1993, we conducted a postal survey to assess the use of autologous blood transfusion (ABT) in the Federal Republic of Germany after reunification. The results of this survey have already been reported in a previous paper, but without differentiation between the "old" and "new" states (former West Germany and former German Democratic Republic, respectively). In the present study, the data of our 1993 survey were further analysed to see if there were differences in the use of ABT between the "old" and "new" states. METHODS. The study is based on data of a 1993 postal survey of German hospitals. Details concerning the performance of the survey have been reported in a previous paper. Briefly, questionnaires were mailed to the anaesthesia departments of 400 randomly selected hospitals in the "old" states and 284 hospitals in the "new" states of the Federal Republic of Germany. The questionnaires contained 36 questions related to general information on the hospital and the use of ABT; 305 completed questionnaires were returned from the "old" states and 197 from the "new" states, response rates of 76% and 69%, respectively. For the present investigation, the responses of the hospitals of the "old" and "new" states were analysed separately. Frequency distributions of categorical variables were analysed by the chi-square test. Because of multiple testing, statistical significance was attained only at the 0.05% level (P < or = 0.0005). RESULTS. There were no significant differences between the "old" and "new" states with respect to hospital size by number of beds, percentage of general and specialised hospitals, and percentage of operations requiring blood transfusion. In both the "old" and "new" states, 9% of the responding hospitals maintained a hospital-based transfusion service, while the other depended on regional blood banks. Preoperative autologous blood donation (PABD) was performed at least "rarely" in 85% and 71% (P = 0.0001), and "mostly" in 20% and 10% (P = 0.0014) of the hospitals in the "old" and "new" states, respectively. Uniformly, the principal uses of PABD were for orthopaedic and cardiac surgery. In 62% and 27% (P < 0.0001) of those hospitals that reported performing PABD, the autologous blood service was run by the anaesthesia department. Preoperative plasmapheresis was performed in 14% and 8% (P = 0.008), and isovolaemic haemodilution in 82% and 56% (P < 0.0001) of the hospitals in the "old" and "new" states, respectively. Automated autotransfusion devices (cell savers) were available in 38% and 19% (P < 0.0001) of the hospitals, respectively. Simple collection devices for perioperative blood salvage were used in 17% and 15% (P = 0.24) of the hospitals in the "old" and "new" states, respectively. CONCLUSION. We conclude that ABT is more widely used in the "old" than the "new" states of the Federal Republic of Germany. ABT is regarded as a desirable alternative to homologous blood transfusion, and in the interest of equal standards of medical care throughout the nation, the use of ABT should be further promoted, especially in the "new" states of the Federal Republic of Germany.

Blood Transfusion, Autologous↗
PubMed1995

Analysis of the precore DNA sequence and detection of precore antigen in liver specimens from patients with anti-hepatitis B e-positive chronic hepatitis.

A number of naturally occurring hepatitis B virus (HBV) mutants unable to synthesize the hepatitis B e antigen (HBeAg) have been identified in patients characterized by HBV DNA and anti-HBe in their serum. Because the analysis of the HBV-associated DNA and antigens in the liver tissue is still not complete, we investigated the precore sequence of HBV DNA and its encoded proteins in the liver tissue of 32 patients positive for HBV DNA and anti-HBe in their serum. Three different groups of patients were identified. Group I (n = 14) was characterized by viral DNA sequences with a G-A transition in the distal precore gene region, thus creating a termination codon (TAG). Liver tissue from this group was negative for HBeAg but positive for hepatitis B core antigen (HBcAg) and a peptide containing the last 10 aminoacids of the precore and the first four aminoacids of the c region. Group II (n = 6) showed variable mutations in base sequences further upstream and negative for HBeAg and the precore peptide. Group III (n = 12) contained wild-type HBV DNA sequences in the tissue and positivity for precore- and core-encoded proteins. We conclude from our study that the group of patients with HBV DNA and anti-HBe in the serum is rather heterogeneous, including HBV DNA mutations in the precore region as well as infection with the wild-type virus being negative for HBeAg in the serum. The precore peptide is produced and expressed in the tissue even when the formation of a stop codon at base 1896 prevents the complete translation of the entire HBe protein.

Base Sequence↗
PubMed1991

[The importance of autologous blood transfusion in the Federal Republic of Germany. Results of a survey carried out in 1989].

The study was designed to evaluate the role of autologous blood transfusion in current clinical practice. METHODS. Standardized questionnaires were distributed to the anesthesia departments of 421 randomly selected hospitals in the 'old' Federal Republic of Germany and West Berlin in August 1989. The questionnaires contained 26 questions relating to (1) the particular hospital, (2) preoperative autologous blood donation (PABD), (3) preoperative plasmapheresis, (4) isovolemic hemodilution, (5) intra- and postoperative autotransfusion, (6) general practice followed in blood transfusion, and (7) blood salvage in children. RESULTS. In all, 207 completed questionnaires (49%) were returned, 12% of which came from university hospitals, 25% from hospitals with more than 500 beds, 58% from hospitals with fewer than 500 beds and 5% from smaller specialized hospitals. Over half (52%) of the responding hospitals were running their own transfusion services or were located in the vicinity of a regional blood bank. The overall proportion of surgical procedures requiring perioperative blood transfusions was 10%. PABD was performed "not at all" in 24% of the hospitals, "rarely" in 28%, "occasionally" in 24%, "frequently" in 10%, and "routinely" in 13%. PABD was standard in 75% of the departments of orthopedic surgery, in 68% of the departments of cardiac surgery, and in 33% of the departments of vascular surgery. In two-thirds of the hospitals reporting the use of PABD, the anesthesia departments were in charge of the autologous blood service. For 64% of the hospitals, liquid storage of whole blood was reported as the standard technique. Patients normally not eligible for homologous blood donation according to established donor criteria were accepted for autologous blood donation at most "occasionally" in 60% of the hospitals, but "frequently" or "mostly" in 36%. Preoperative autologous plasmapheresis was performed when major intraoperative blood loss was anticipated in 12% of the hospitals. Isovolemic hemodilution was performed "not at all" in 30% of the hospitals, "rarely" in 17%, "occasionally" in 25%, "frequently" in 14%, and "mostly" in 12%. The reasons most frequently given for not performing hemodilution were "too time-consuming" (41%) and "too little blood-saving effect" (32%). Autotransfusion devices were available in 40% of the hospitals. Others deemed such devices "badly needed" (5%) or "desirable" (43%), while 45% found them "not necessary." The principal use of intraoperative autotransfusion was in cardiac surgery (79% of the departments), orthopedics (47% of the departments) and vascular surgery (45% of the departments). In 29% of the responding hospitals autotransfusion devices were also used for postoperative autotransfusion ("seldom" in 7%, "occasionally" in 10%, "frequently" in 6%, "mostly" in 6%). In the absence of cardiopulmonary disease, hemoglobin concentrations below 8-10 g/dl were considered an indication for blood transfusion. In patients with compromised cardiopulmonary function the lowest acceptable level was 10-12 g/dl. Blood salvage techniques are obviously rarely used in children. Experiences with PABD in children were reported by 14.5% of the hospitals, experience with isovolemic hemodilution by 22% and with intra- and postoperative autotransfusion in 18% and 12.5% of the hospitals, respectively. Preoperative plasmapheresis was performed in children in 3.5% of the hospitals. CONCLUSIONS. Although the present sample is not representative on a national level, our findings allow the conclusion that the simple techniques of both preoperative autologous blood donation and isovolemic hemodilution are unduly neglected in surgical and anesthetic practice, whereas even smaller hospitals are fairly well equipped with sophisticated autotransfusion devices.

Blood Transfusion, Autologous↗
PubMed1989

Unsatisfactory specificities and sensitivities of six enzyme immunoassays for antibodies to hepatitis B core antigen.

To examine the consistency and comparability of anti-hepatitis B core antigen (anti-HBcAg) assays, four blood donation centers of the Red Cross in the Federal Republic of Germany tested 4,080 unselected blood donors with six different tests in parallel. Confirmation testing of reactive samples was done in the National Reference Center for Viral Hepatitis. Depending on the test kit used, 4.1 to 9.9% of serum samples were initially positive and 2.9 to 7.5% were repeatedly positive. Sixteen percent of serum samples were positive in at least one test but only three percent were positive in all six tests. Statistical analysis of frequency distribution of optical densities for each test suggested that there should be a correction of the cutoff values. This reduced the number of false-positive results by half, but a significant proportion of discrepant results could not be resolved. The lack of specificity and consistency requires cautious interpretation of isolated anti-HBcAg results in clinical specimens. Screening of predominantly anti-HBcAg-negative populations (e.g., blood donors) by the current anti-HBcAg test kits will almost necessarily give unsatisfactory results.

Blood Donors↗
PubMed1986

Treatment of hepatitis B surface antigen (HBsAg)-positive chronic hepatitis with recombinant leucocyte alpha-A interferon.

A total of 32 individuals with HBsAg-positive and anti-delta-negative chronic hepatitis were treated with recombinant alpha-A interferon in phase I and phase II studies. In 5/32 patients HBsAg could be eliminated and in 19/32 individuals HBeAg became negative including all those who also eliminated HBsAg. Side-effects were tolerable in most patients and were readily reversible upon discontinuation of interferon therapy. In conclusion, treatment of HBsAg-positive chronic hepatitis with interferon seems to be a promising therapeutic approach. Future studies will have to establish the optimal dose, duration of treatment and factors predicting a favourable outcome of the treatment.

Drug Evaluation↗
PubMed1982

[Preparation and testing of a hepatitis B vaccine (author's transl)].

Starting with 41.5 l of plasma from anti-HBe positive carriers of HBs antigen, 11,400 doses of a hepatitis B vaccine with 42 micrograms HBsAg-protein and 11,300 national units HBsAg activity per dose were obtained. After purification, HBsAg is obtained in 99% purity with a yield of more than 90% protein. A possible residual infectivity was inactivated by a diluted formalin solution. The infectivity test in chimpanzees confirmed the absence of infectious hepatitis viruses (HBV and nonA-nonB). In guinea pigs the immunogenicity of the vaccine was comparable to that of the reference preparation from the U.S. National Institute of Health. The presence of Al(OH)3 in the vaccine increased the anti-HBs titre by factors of 30-50. After vaccination with two doses 41 of 45 persons became anti-HBs positive, with three doses 42 of 45 persons developed anti-HBs. Median anti-HBs titre after the third doses: schedule I (three doses in intervals of 6 weeks) 427 mWHO-U/ml; schedule II (two doses at an interval of 4 weeks, third doses 4 months after the first doses) 1535 mWHO-U/ml. The vaccine was well tolerated. There were minor local reactions only.

Animals↗
PubMed1980

[Follow-up study on antibody dependent cell-mediated cytotoxicity and cell-mediated cytotoxicity to HBs-antigen conjugated target cells in patients with hepatitis B (author's transl)].

Results of a follow up study on ADCC and CMC to HBs antigen conjugated target cells in patients with hepatitis B are given. The cytotoxic reaction was measured immediately after onset of the disease, three weeks and three months thereafter CMC was increased over the whole observation period. The results in hepatitis B patients were significantly different to those in normal controls. The ADCC in the presence of an antiserum to HBs antigen was in patients with hepatitis B immediately after onset of the disease reduced in comparison to the controls; it increased during the three months to the values of the controls in patients with uncomplicated disease. Experiments with isolated lymphocyte populations showed that the ADCC is mainly dependent on Fc receptor bearing lymphocytes whereas the CMC is mediated by T-cells and Fc-receptor bearing cells.

Antibody-Dependent Cell Cytotoxicity↗
PubMed1980

Experimental non-A, non-B hepatitis: four types of cytoplasmic alteration in hepatocytes of infected chimpanzees.

On the occasion of an outbreak of non-A, non-B hepatitis in a plasmapheresis centre (81 cases, incubation period: 3--6 weeks) a pool of 12 plasma samples was obtained in the early phase of increasing transaminases. Two chimpanzees were inoculated, each receiving 12 ml of the pooled plasma. After an incubation period of 10--12 weeks a mild non-A, non-B hepatitis developed. Serum transaminases were slightly elevated. Needle biopsies, taken fortnightly, showed a slight activation of Kupffer cells (6--8 weeks), single cell necroses, and infiltration of the portal tracts (10--13 weeks). Electron microscopically four types of cytoplasmic change, were found in hepatocytes and assumed to be specific for the infection, Type I: Sponge-like inclusion (6 weeks after inoculation) composed of a dense matrix and irregularly arranged membranes. Type II: Attaching curved membranes (8 weeks), developing by close apposition of two cisternae of smooth endoplasmic reticulum. Type III: Cylindrical complexes (10 weeks), already described in literature. Type IV: Microtubular aggregates, usually neighbouring type III structures. The findings suggest 1) that the agent of the present infection is, at least in part, identical with that of the long incubation type of experimental non-A, non-B hepatitis, and 2) that ultrastructural alterations may precede manifest hepatitis.

Animals↗
PubMed1979

[Experiments for the development of a hepatitis B vaccine: immunogenicity of HBsAg in guinea pigs (author's transl)].

Hepatitis B surface antigen (HBsAg) was purified from human plasma by gel chromatography, isopyknic centrifugation, and zonal centrifugation. The final product had about 60% of the original activity and was essentially free from hepatitis B virus particles (HBV) and plasma proteins. Treatment with formaldehyde concentrations up to 0.1% for inactivation of residual infectivity did not significantly reduce antigenicity in vitro and immunogenicity in guinea pigs. Adsorption to aluminum hydroxide resulted in 16-fold higher concentrations of antibody against HBsAg (anti-HBs) than did injection of soluble HBsAg. After two injections of 0.2 microgram HBsAg, which was treated with 0.1% formaldehyde and absorbed to aluminum hydroxide, the median titer of anti-HBs in guinea pigs was 4 IU/ml (normal value in human hepatitis B convalescents: about 0.1) for 1 year without further injections. When guinea pigs received 12 equivalents of homologous anti-HBs serum before the first injection of adsorbed HBsAg, the same anti-HBs titers were found after the booster injection as in animals which had not been passively immunized. A simultaneous application of an experimental HBsAg vaccine and hepatitis B immunoglobulin would probably decrease the potential risk of HBV infections caused by the vaccine itself and also produce rapid protection. To establish absence of HBV as completely as possible, the vaccine should be produced from anti-HBe-positive plasma by efficient purification procedures and it should be inactivated by formalin.

Aluminum Hydroxide↗
PubMed1979

Detection of antibodies to Sendai virus by enzyme-linked immunosorbent assay (ELISA).

An enzyme-linked immunosorbent assay (ELISA) for the detection of antibodies to Sendai virus, a paramyxovirus, is described. The assay was found to be about 20-fold more sensitive than the hemagglutination inhibition assay. Differentiation between virus specific IgG and IgM is possible. The test appears to be especially useful in the study of early events in antibody formation in vivo as well as in vitro.

Animals↗