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M Ackermann

Publications and source records attributed to M Ackermann.

At least 91 records · Page 5Linked to original sources
PubMed1994

[Amalgam as the measure in filling therapy. A determination of its place].

As the value of amalgam restorations is increasingly being questioned in modern dentistry, the clinical potential of amalgam restorations in general has been evaluated in this literature review. The major factors limiting the longevity of amalgam restorations are operator- and patient-related. Both factors will likewise influence the longevity of any new restorative concepts. Nevertheless, amalgam restorations remain the standard against which alternative materials are evaluated. Amalgam restorations are slowly loosing ground to the use of tooth-colored materials, which are gaining in popularity. However, amalgam can not currently be withdrawn from the list of possible restorative materials used for patients in Switzerland.

Costs and Cost Analysis↗
PubMed1994

[Comparison of two ELISA systems for the detection of antibodies against IBR/IPV and against enzootic bovine leukemia virus].

Sensitivity and specificity of two ELISA systems for the detection of antibodies to Bovine Herpes-virus 1 (BHV1; IBR/IPV) were tested by using 214 sera of cattle with predetermined history of BHV1 infection and freedom from BHV1 infection, respectively. With these sera as "gold-standard", the sensitivity of ELISA1 (HerdCheck: Anti-IBR) appeared to exceed 98%, whereas for ELISA2 (Checkit: Trachitest) a sensitivity of between 94 and 99.3% was determined. The specificity of ELISA1 amounted to at least 96.9%, whereas for ELISA2 it ranged apparently from 81.5 to 98.5%. When applied in routine testings of serum samples, the two ELISA systems correlated extremely well. With each test, only 3 of 1431 samples gave contradictory results. In all these cases, alternative tests suggested that the contradictions represented false-positive reactions. A similar correlation was observed when milk samples in the place of sera were probed. The serum and milk samples were additionally tested using two corresponding ELISA systems (obtained from the same manufacturers) for the detection of antibodies to Bovine Leukemia virus (BLV). The sensitivity and specificity of these tests could not be determined because of lack of samples with known history of infection. The results of the tests, however, correlated very well. Only 6 of 1431 sera reacted in a contradictory way. These observations indicate that the kits tested in this study, both for the detection of antibodies to BHV1 and to BLV, meet high quality standards. Possibilities to improve the kits were still detected.

Animals↗
PubMed1993

Preliminary characterization of a monoclonal antibody specific for a viral 27 kD glycoprotein family synthesized in porcine epidemic diarrhoea virus infected cells.

We describe a new monoclonal antibody No. 204 (mcAb 204) which recognized a family of four polypeptides, consisting of a 27kD, a 24/23kD double band and a 19kD protein present within PEDV infected cell lysates. These proteins were identified by immunoprecipitation as well as by staining of immunoblots. In infected Vero cell cultures, the synthesis of the 27kD protein was initiated between 6 and 8 hours post inoculation. The 24/23kD double band and the 19kD protein were only detectable later. At least the 27 and the 24/23kD proteins were apparently glycosylated and present in purified virions. Pulse-chase as well as solubilization experiments indicated that the faster migrating bands represented processed products of the 27kD glycoprotein. The nature of the processing is not known at present. We suggest that the 27kD protein family may represent the integral membrane protein M of PEDV. Since this protein is highly abundant in virions as well as in infected cells, and since mcAb 204 is able to react with its antigen under various conditions, this monoclonal antibody may be useful to further studies of the M-protein of PEDV. In addition, it may provide a useful tool for routine diagnosis.

Animals↗
PubMed1993

Sequence analysis of the nucleocapsid protein gene of porcine epidemic diarrhoea virus.

The nucleotide (nt) sequence of 1.7 kbp cDNA representing the 3' end of the PEDV genome has been determined. Viral RNA was reverse transcribed and the cDNA was amplified by polymerase chain reaction using degenerate primers. The sequences of the primers were based on conserved regions of coronaviral genomes. A 1323 nt open reading frame (ORF) showed good homology to the nucleocapsid (N) gene of other coronaviruses. The greatest homologies at the amino acid and the nt levels were observed with Human Coronavirus 229E. A second 336 nt ORF, which might encode a leucine-rich protein, was found within the N gene. Between the 3' end of the N gene and the poly(A) tail was a sequence of eleven nt, which is conserved among the other sequenced coronaviruses. Finally, a seven base sequence similar to the conserved intergenic sequences was present 5' to the N gene. These results confirm the classification of PEDV as a coronavirus.

Base Sequence↗
PubMed1993

Low dose megestrol acetate can abrogate cachexia in advanced tumor patients receiving systemic interferon-alpha and/or interleukin-2 based antineoplastic therapy.

The progression of advanced malignancies is often associated with anorexia and cachexia, especially when patients receive concomitant systemic antitumor treatment. Megestrol acetate has been reported to increase appetite and body weight, and a linear dose-response relation for doses from 160 up to 1600 mg/day has been proposed. In our study, we were able to show that megestrol acetate at doses as low as 60 mg/day was sufficient to abrogate anorexia and weight loss. In contrast to previous studies, this effect was achieved while patients continued systemic antineoplastic therapy.

Anorexia↗
PubMed1993

Sequence determination of the nucleocapsid protein gene of the porcine epidemic diarrhoea virus confirms that this virus is a coronavirus related to human coronavirus 229E and porcine transmissible gastroenteritis virus.

The nucleotide sequence of 1.7 kbp cDNA, comprising the region nearest the 3' end of the genome of the porcine epidemic diarrhoea virus (PEDV), has been independently determined for two European isolates of PEDV. Almost identical results were obtained for the two isolates, which were derived from cases of PEDV infection in Belgium and Britain in 1977 and 1987, respectively. The sequences contained a 1323 nucleotide (nt) open reading frame (ORF), which showed moderate identity to the nucleocapsid (N) gene of other coronaviruses. The greatest similarity at both the nucleic acid and protein levels was to the human coronavirus 229E. The PEDV N gene was, however, notably larger than that of the human 229E and porcine transmissible gastroenteritis viruses. This reflects the presence of a putative insertion of approximately 135 nt located towards the middle of the N gene. A second 336 nt ORF, which might encode a leucine-rich protein similar to, but shorter than, the bovine coronavirus internal protein was found within the PEDV N gene. Several RNA motifs typical of coronaviruses were also observed. These results confirm the earlier provisional classification of PEDV as a coronavirus.

Amino Acid Sequence↗
PubMed1993

Metabolism of benzbromarone in man: structures of new oxidative metabolites, 6-hydroxy- and 1'-oxo-benzbromarone, and the enantioselective formation and elimination of 1'-hydroxybenzbromarone.

1. The uricosuric drug benzbromarone is extensively metabolized in man and two main metabolites are formed: the previously characterized 1'-hydroxybenzbromarone (metabolite M1) and an arylhydroxybenzbromarone (metabolite M2) of unknown structure. A dimethyl derivative was isolated from urine after methylation and was characterized by gas chromatography-mass spectrometry (g.l.c.-m.s.) and high resolution nuclear magnetic resonance spectroscopy as 4''-O-methyl-6-methoxybenzbromarone; the structure of M2 therefore is 6-hydroxybenzbromarone. 2. A minor metabolite was similarly characterized as 1'-oxobenzbromarone by comparison with authentic synthetic samples and is a product of biodegradation and not an artifact derived from the in vitro oxidation of 1'-hydroxybenzbromarone. Further minor metabolites were detected and were provisionally characterized by g.l.c.-m.s. after derivatization and include: 2'-hydroxybenzbromarone (an isomer of 1'-hydroxybenzbromarone); 1',6-dihydroxybenzbromarone; dihydroxy-aryl-benzbromarone; and two structure isomers of 6-hydroxybenzbromarone. Debrominated metabolites were not detectable. 3. Benzbromarone is hydroxylated in vivo at the prochiral centre C1' to 1'-hydroxybenzbromarone; analysis of 1'-hydroxybenzbromarone from plasma and urine extracts by h.p.l.c. using a chiral column revealed that two peaks were eluted which showed a mean enantiomeric ratio of 2.1 for plasma and 7.3 for urine; these data demonstrate that the formation and elimination of this metabolite is enantioselective; the absolute configuration of the 1'-chiral centre is presently unknown.

Adult↗
PubMed1992

Interactions of bovine and caprine herpesviruses with the natural and the foreign hosts.

Bovine herpesvirus 1 (BHV1) and caprine herpesvirus 1 (CapHV1) are useful models to study virus-host interactions, as well as pathogenicity and latency, when comparing the outcome of infection in the natural and the foreign hosts. Molecular seroepidemiological analyses revealed that cross-reacting antibodies were mainly induced by glycoprotein gI (gB analogue), by the major capsid protein and by nonstructural proteins, whereas the most virus-specific antibodies were elicited by glycoproteins gIII and gIV. These glycoproteins, especially gIII (gC analogue), might therefore play an important role in the virus-host-interactions. As a basis for further studies, we re-evaluated observations concerning experimental infections with BHV1 and CapHV1 in the natural and the foreign hosts. All parameters indicated that both viruses were able to infect either host, but that the pathogenicity was restricted to the natural host. Latent virus could be reactivated exclusively from cows infected with BHV1. It was possible neither to reactivate BHV1 from goats, nor to reactivate CapHV1 from either species. The experiments indicated that the outcome of infection in the natural and the foreign host is dependent on host and viral factors, whereby gIII is only one important virus component involved. Further investigations in the host and host cell range of BHV1 and CapHV1 will help to clarify the role of factors responsible for virus-host-interactions.

Animals↗
PubMed1992

Approaches to the identification of non-essential genes of African swine fever virus.

It is poorly understood why vaccines could not be developed for the control and prevention of African swine fever (ASF) virus infection. The aim of our study was to identify genes non-essential for ASF virus replication because there were indications that certain viral gene products, which apparently are non-essential for viral replication, conferred protection from death due to ASF. A cosmid library representing the genome of ASF virus strain France 64 was established and characterized. Then, in order to inactivate viral genes by insertion, the beta-galactosidase (beta-gal) gene was introduced either randomly or at specific locations of selected cloned DNA fragments. These constructions were transfected into cells which had been previously infected with a cell-culture-adapted viral strain in order to allow the generation of recombinant progeny virus. Viable recombinant progeny was identified by at least one of the following means: (1) expression of beta-gal; (2) detection of beta-gal specific DNA by plaque hybridization, and (3) absence of a functional product of the inactivated gene. Presently, we are characterizing a recombinant virus with an insertionally inactivated thymidine kinase gene.

African Swine Fever Virus↗
PubMed1992

An ELISA for detection of antibodies against porcine epidemic diarrhoea virus (PEDV) based on the specific solubility of the viral surface glycoprotein.

Viral proteins of porcine epidemic diarrhoea virus (PEDV) were extracted from the cytoplasm of infected Vero cells using hypotonic conditions and a non-ionic detergent. Both the pH and the NaCl concentration of the extraction buffer were varied in attempts to increase the solubility of the virion spike glycoproteins (S-protein) and of the nucleocapsid proteins (N-protein). Monoclonal antibodies, hyperimmune sera and convalescent pig sera were used to identify and monitor these proteins by immunoprecipitation and Western blots. The solubility of the S-protein was optimal at pH 4, whereas that of the N-protein was optimal at pH 9. Consequently, it was possible to enrich for either S-protein or N-protein; increases in the NaCl concentration of the buffer were of no advantage in this respect. Enriched preparations of the S-protein and N-protein were used as ELISA antigen for the S-ELISA and N-ELISA, respectively. The S-ELISA proved to be the more effective of the two immunoassays. Antibodies against S-protein remained detectable for longer periods of time than anti-N-protein antibodies in the sera of PEDV-infected pigs. Using this ELISA of increased sensitivity, it was observed that only a small number of farms in Switzerland had been infected with PEDV.

Animals↗
PubMed1992

Immunohistological diagnosis of rabbit haemorrhagic disease (RHD).

In the present study the diagnostic use of a biotinylated serum from an immune rabbit was investigated by means of an Avidin-Biotin-Complex (ABC)-Peroxidase method on paraffin sections. 15 cases of RHD which had been verified histologically and/or by haemagglutination test (HA), 4 suspected cases and 3 cases without history of RHD were included (cases 1 to 22). From 5 prospective cases a wider tissue range was examined (cases 23 to 25 and 29 to 30). Furthermore lungs, liver and placenta of 3 fetuses from a RHD affected dam were investigated (cases 26 to 28). The 20 typical cases had intense intranuclear and diffuse intracytoplasmic immunostaining of hepatocytes, predominantly in the periportal areas. In some cases there was also positive staining of macrophages in the lungs (4 cases), spleen (4 cases) and in lymph nodes (1 case). Positive granular staining in the renal mesangial cells of the glomeruli was observed in 1 case. No positive staining was observed in the 3 negative cases. In contrast to other reports (4), crossreactivity of these antigens to Porcine Parvovirus (PPV) could not be confirmed. Furthermore the RHD virus (RHDV) seems not to crossreact with Feline and Bovine Parvoviruses.

Animals↗
PubMed1992

Rapid and biologically safe diagnosis of African swine fever virus infection by using polymerase chain reaction.

In order to circumvent the need for infectious virus for the diagnosis of African swine fever (ASF), we established the polymerase chain reaction (PCR) technique for the detection of ASF virus (ASFV) DNA. A 740-bp fragment that originated from the conserved region of the viral genome was partially sequenced. From this sequence, four PCR primers and one oligonucleotide probe were designed and synthesized. A specific 640-bp PCR product was amplified by using oligonucleotides 1 and 5 as primers and extracts of the following samples as templates: organs and plasma obtained from ASFV-infected pigs, ASFV-infected cell cultures, and cloned DNA fragments containing the same conserved genomic region as that in the original 740-bp clone. No specific reaction products were observed in the corresponding controls. The identities of the PCR products were confirmed either by a second amplification with nested primers or by hybridization with a specific, biotinylated oligonucleotide probe. PCR proved to be a quicker and more sensitive method than virus isolation followed by the hemadsorption test when spleen and plasma samples from experimentally ASFV-infected pigs were tested. Furthermore, cloned virus DNA could be used as a positive control in the place of a live virus control. This is advantageous whenever the use of live virus is undesirable.

African Swine Fever↗
PubMed1990

Round table on infectious bovine rhinotracheitis/infectious pustular vulvovaginitis virus infection diagnosis and control.

The current situation of infectious bovine rhinotracheitis/infectious pustular vulvovaginitis infection in various European countries is reviewed. Whilst some have a high serological prevalence and use live virus vaccines to control the disease, others have a low prevalence and two countries (Denmark and Switzerland) have national eradication schemes which are almost complete. Serology remains important for diagnosis although other tests such as delayed cutaneous hypersensitivity may have a role to play. New tests such as polymerase chain reaction may find increasing application where high sensitivity is required, such as the detection of virus in semen.

Animals↗
PubMed1990

Eradication of infectious bovine rhinotracheitis in Switzerland: review and prospects.

Ten years after the first outbreak of infectious bovine rhinotracheitis (IBR) in Swiss dairy cows, the national cattle herd is almost free from infection with IBR virus (bovine herpesvirus 1, BHV 1). The national programme for the eradication of IBR was divided into four phases: (1) Prevention of transmission of the infection by restrictions on trade of bovines and assessment of the prevalence of cattle with antibodies to BHV 1. (2) Slaughtering animals with antibodies to BHV 1 in order to eradicate BHV 1 from breeding herds. (3) Detection and eradication of further BHV 1 reservoirs (e.g. fattening cattle). (4) Monitoring programme and legal actions in order to maintain the favourable situation. Approximately 50,000 animals were slaughtered in the course of the eradication of IBR. The total costs amounted to approximately SFr. 110,000,000 over 10 years. The costs for maintaining the situation are estimated at approximately SFr. 5,000,000 per annum.

Animals↗
PubMed1990

Inactivation of foot and mouth disease virus in skimmed milk with propionic acid, citric acid and hydrogen peroxide.

In order to protect farm animals from infections such as foot and mouth disease (FMD) and tuberculosis, the pasteurisation of milk and milk products designated for the feeding of animals is compulsory in Switzerland. Nowadays, milk products are often treated chemically with acids or with hydrogen peroxide in order to keep bacterial contamination low. The capacity of these chemical treatments to inactivate FMD virus in skimmed milk within 6 h at 5 degrees C was tested in this study. The results indicated that the addition of 0.1%-0.3% of consumable acids, such as citric acid or propionic acid, could not guarantee the complete inactivation of FMD virus in skimmed milk. Similar results were obtained both with FMD virus deliberately added to skimmed milk and with skimmed milk obtained from naturally infected cows. Hydrogen peroxide in concentrations of 0.1%-0.3% was also an ineffective means of controlling the risk of FMD virus transmission from contaminated milk.

Animals↗
PubMed1990

[Current information on the subject of African horse sickness (AHS)].

The objective of the present review was to summarize current knowledge of African horse sickness (AHS), based on available literature (which is nonetheless relatively scant) and recent information obtained from the O.I.E. Brief description is made of the biology of AHS virus (an arbovirus, transmitted by Culicoides imicola), isolation of the agent, diagnosis by serotyping procedures, and preventive measures (such as protection of horses from insect infestation, or vaccination programs) which may be taken. The recent outbreaks in Spain, Portugal, and Morocco, have demonstrated that much more research on this disease is required.

Africa↗
PubMed1989

Antibodies to foot-and-mouth disease virus infection associated (VIA) antigen: use of a bioengineered VIA protein as antigen in an ELISA.

An enzyme-linked immunosorbent assay (ELISA) to detect antibodies to foot-and-mouth disease (FMD) virus infection associated (VIA) antigen (viral RNA polymerase) in cattle sera, was developed using a bioengineered VIA (BioVIA) protein antigen. Compared with the classical immunodiffusion test, with viral RNA polymerase purified from infected cell cultures as antigen, this ELISA was more sensitive. However, depending on the cattle population examined, sera with antibodies to viral RNA polymerase, probably due to infection with other picornaviruses, were detected. Despite these observations, the ELISA using BioVIA provided a rapid answer as to whether or not FMD virus circulated in a given herd of cattle. The main advantage of this ELISA is its absolute safety, since in no step of the antigen production was infectious or uninfectious FMD virus involved. The test can therefore be performed under normal laboratory conditions and no isolation units are needed as they are for the immunodiffusion test.

Animals↗