Biomedical subjects

Norbert Nowotny

Publications and source records attributed to Norbert Nowotny.

33 records · Page 2Linked to original sources

PubMed2004

Purification and characterization of antimicrobial peptides from the skin secretions of the mink frog (Rana septentrionalis).

Skin secretions were obtained from male, female, and juvenile specimens of the mink frog (Rana septentrionalis) by electric stimulation and shown to contain 10 peptides that differentially inhibited the growth of microorganisms. The elution profiles of secretions from the three groups following reverse-phase HPLC were almost identical indicating that there were no major sexual or developmental differences in chemical composition. Four peptides of the brevinin-1 family, with potent antimicrobial activity and strong hemolytic activity, two members of ranatuerin-2 family and three members of the temporin family, were purified and characterized structurally. A 21-amino-acid C-terminally alpha-amidated peptide (GIWDTIKSMGKVFAGKILQNL.NH(2)) with broad-spectrum antimicrobial activity was also isolated from the skin secretions. This peptide shows limited structural similarity with the N-terminal region of brevinin-2 peptides previously isolated from R. temporaria skin but lacks the C-terminal cyclic heptapeptide domain associated with this family. Molecular and morphological data support the placement of R. septentrionalis in the R. catesbeiana species group, but analysis based upon the distribution of the molecular forms of the antimicrobial peptides is indicative of a closer phylogenetic relationship between R. septentrionalis and the frogs of the R. pipiens and R. boylii groups.

Amino Acid Sequence↗

PubMed2004

Investigations into shaking mink syndrome: an encephalomyelitis of unknown cause in farmed mink (Mustela vison) kits in Scandinavia.

An apparently novel neurological disease clinically characterized by shaking, tremors, seizures, staggering gait, and ataxia was first observed in farmed mink kits in Denmark in 2000 and subsequently in Sweden, Denmark, and Finland in 2001, and again in Denmark in 2002. Lymphoplasmacytic encephalomyelitis was found in the affected kits. The lesions were most severe in the brainstem and cerebellum and consisted of neuronal degeneration and necrosis, neuronophagia, focal and diffuse gliosis, perivascular cuffs formed by lymphocytes, plasma cells and macrophages, and segmental loss of Purkinje cells. Testing was conducted to determine the cause of the disease, including general virological investigations (virus culture, negative-staining electron microscopy, immunoelectron microscopy, polymerase chain reaction for herpesviruses, adenoviruses, pestiviruses, and coronaviruses), tests for specific viral diseases (canine distemper, Borna disease, Louping ill, West Nile virus infection, tick-borne encephalitis, Aleutian disease), tests for protozoa (Toxoplasma gondii, Neospora caninum, Encephalitozoon cuniculi), bacteria (general culture, listeria, Clamydophila psittaci), and intracerebral inoculation of neonatal mice. The results of all these investigations were negative. One group of 3 mink kits inoculated intracerebrally with brain homogenate of affected mink developed clinical signs and histological lesions similar to those observed in naturally infected mink. Based on the histopathological features, it is postulated that the disease is caused by a yet unidentified virus.

Animals↗

PubMed2003

A melittin-related peptide from the skin of the Japanese frog, Rana tagoi, with antimicrobial and cytolytic properties.

Two peptides with antimicrobial and cytolytic properties were purified from an extract of the skin of Tago's brown frog Rana tagoi. The primary structure of one peptide (FLPILGKLLS(10)GIL.NH(2)) identifies it as a member of the temporin family, whereas the second peptide (AIGSILGALA(10)KGLPTLISWI(20)KNR.NH(2)) displays 78% sequence identity to melittin from the venom of the honeybee Apis florea. Compared with melittin, the melittin-related peptide (MRP) was equipotent in inhibiting the growth of the Gram-positive bacterium Staphylococcus aureus, 5-fold less potent against the Gram-negative bacterium Escherichia coli and against the fungal pathogen, Candida albicans. MRP was 13-fold less hemolytic than melittin against human erythrocytes and 4- and 5-fold less cytolytic against mouse EL4 T-lymphoma-derived cells and L929 fibroblasts, respectively. However, at non-cytotoxic concentrations (<or=8 microM), MRP did not protect HeLa cells from cell death produced by human rhinovirus type 2 infection.

Amino Acid Sequence↗

PubMed2003

Usutu virus activity in Austria, 2001-2002.

Usutu virus (USUV), a member of the mosquito-borne clade within the Flaviviridae family, was responsible for avian mortality in Austria in 2001. In 2002, the virus continued to kill birds, predominantly blackbirds. High numbers of avian deaths were recorded within the city of Vienna and in surrounding districts of the federal state of Lower Austria, while single die-offs were noticed in the federal states of Styria and Burgenland. A total of 72 birds were submitted for laboratory examination, 30 of which tested positive for USUV by immunohistochemistry and/or polymerase chain reaction. Laboratory-confirmed cases of USUV infection originated from the federal states of Vienna and Lower Austria only. The data show that (i) USUV has managed to overwinter and has been able to establish a transmission cycle in Austria, (ii) the virus seems to have become a resident pathogen of Austria with a tendency to spread to other geographic areas, and (iii) the surveillance of dead blackbirds is a useful sentinel system for monitoring USUV activity.

Animals↗

PubMed2003

Feline orthopoxvirus infection transmitted from cat to human.

We report the case of a 56-year-old female patient who presented with an inflamed, ulcerated lesion on the left side of her neck after contact (scratch) with a cat living in the patient's house. Satellite lesions developed despite local treatment and parenteral clindamycin. Histopatholgic examination and the Tzanck test showed evidence of a viral infection. Subsequent transmission electron microscopy of scrap tissue and material from a fresh pustule exhibited multiple typical poxvirus particles, predominantly in remnants of scaled-off layers of degenerated keratinocytes, and virus particles in intermingled phagocytes, leading to the diagnosis of feline Orthopoxvirus (cowpox virus) infection. These results were verified by polymerase chain reaction and sequencing. Concern has been raised as to whether discontinuation of smallpox vaccine would cause an increase in Orthopoxvirus infection, but this has not yet shown to be the case.

Acyclovir↗

PubMed2003

Development and evaluation of PCR assays for the detection of Paenibacillus larvae in honey samples: comparison with isolation and biochemical characterization.

PCR assays were developed for the direct detection of Paenibacillus larvae in honey samples and compared with isolation and biochemical characterization procedures. Different primer pairs, designed from the 16S rRNA and the metalloproteinase precursor gene regions, and different DNA extraction methods were tested and compared. The sensitivity of the reactions was evaluated by serial dilutions of DNA extracts obtained from P. larvae cultures. The specificity of the primers was assessed by analyzing related Paenibacillus and Bacillus strains isolated from honey. The PCR assays also amplified these related bacteria, but at lower sensitivity. In the next step, the PCR assays were applied to contaminated honey and other bee products originating from 15 countries. Lysozyme treatment followed by proteinase K digestion was determined to be the best DNA extraction method for P. larvae spores. The most sensitive primer pair detected P. larvae in 18 of 23 contaminated honey samples, as well as in pollen, wax, and brood. Honey specimens containing saprophyte bacilli and paenibacilli, but not P. larvae, were PCR negative. Although the isolation and biochemical identification method (BioLog) showed higher sensitivity and specificity, PCR proved to be a valuable technique for large-scale screening of honey samples for American foulbrood, especially considering its rapidity and moderate costs.

Animals↗

PubMed2003

Idiopathic acute onset myelopathy in cheetah (Acinonyx jubatus) cubs.

Numerous cases of ataxia, hind limb paresis, and paralysis have occurred in cheetah (Acinonyx jubatus) cubs over the past 10 yr within the European Endangered Species Program population, including 12 in mainland Europe, two in the British Isles, one in Namibia, and one in Dubai. The condition is the most important medical factor limiting European cheetah population growth. Eight cubs at the Salzburg Zoo, Austria, were affected. They demonstrated upper motor neuron lesions when alive and bilateral, symmetrical myelin degeneration of the spinal cord on necropsy. Ballooning of myelin sheaths surrounded mostly preserved axons, and no spheroids, characteristic of acute axonal degeneration, were found. Myelin loss markedly exceeded axonal degeneration. The syndrome's etiology is unclear, although viral, bacterial, parasitic, genetic, nutritional-metabolic, toxic, and physical causes have been considered.

Acinonyx↗

PubMed2003

[Sero-epidemiological studies of zoonotic infections in hunters--comparative analysis with veterinarians, farmers, and abattoir workers].

The aim of this study was to investigate seroprevalences to zoonotic pathogens in hunters, to compare the results with other predisposed occupational groups already investigated and to propose preventive measures. Blood samples were taken from 146 male and 3 female hunters from the provinces of Styria and Burgenland in the south-east of Austria and anamnestic data were obtained using a questionnaire. The serological investigations included the following bacterial, viral and parasitic zoonotic agents or zoonoses, respectively (antibody prevalence rates in brackets): borreliosis (IgG 42%, IgM 7%), brucellosis (1%), chlamydiosis (3%), ehrlichiosis (IgG 15%, IgM 3%), leptospirosis (10%), tularaemia (3%), Q fever (0%), encephalomyocarditis virus (EMCV, 15%), Puumala-Hantavirus (10%), Newcastle Disease virus (4%), Echinococcus multilocularis/E. granulosus (5%/11%), toxocariasis (17%). Particularly striking in comparison with the control group and the veterinarians, farmers and slaughterhouse workers examined in earlier projects were the high seroprevalences to Borrelia burgdorferi sensu lato, Ehrlichia spp., Leptospira interrogans, E. granulosus and E. multilocularis, encephalomyocarditis, Puumala-Hantavirus and Newcastle Disease virus as well as to Brucella abortus and Francisella tularensis. The present study indicates that hunters are especially exposed to zoonotic pathogens.

Adult↗

PubMed2002

Phylogenetic analysis of acute bee paralysis virus strains.

Reverse transcription-PCR assays have been established for a quick, sensitive, and specific diagnosis of acute bee paralysis virus (ABPV), a common virus of the honeybee (Apis mellifera), directly from clinical samples. A 3,071-nucleotide fragment of the ABPV genome, which includes the entire capsid polyprotein gene, was amplified from Austrian, German, Polish, and Hungarian ABPV samples and sequenced, and the sequences were compared. The alignment of a smaller fragment with ABPV sequences from the United States and the United Kingdom revealed nucleotide identity rates between 89 and 96%, respectively. Phylogenetic trees which display the molecular relationship between the viruses of different geographic origin were constructed.

Animals↗

PubMed2002

Fatal infection of a pet monkey with Human herpesvirus.

Concerns have been raised about pet monkeys as a potential threat to humans. We report the opposite situation, a danger to pets that arises from humans. Similar to herpesvirus B (Cercopithecine herpesvirus 1), which endangers humans but not its host species, Human herpesvirus 1 can act as a "killer virus" when crossing the species barrier to New World monkeys.

Animals↗

PubMed2002

Emergence of Usutu virus, an African mosquito-borne flavivirus of the Japanese encephalitis virus group, central Europe.

During late summer 2001 in Austria, a series of deaths in several species of birds occurred, similar to the beginning of the West Nile virus (WNV) epidemic in the United States. We necropsied the dead birds and examined them by various methods; pathologic and immunohistologic investigations suggested a WNV infection. Subsequently, the virus was isolated, identified, partially sequenced, and subjected to phylogenetic analysis. The isolates exhibited 97% identity to Usutu virus (USUV), a mosquito-borne Flavivirus of the Japanese encephalitis virus group; USUV has never previously been observed outside Africa nor associated with fatal disease in animals or humans. If established in central Europe, this virus may have considerable effects on avian populations; whether USUV has the potential to cause severe human disease is unknown.

Africa↗

PubMed2001

Conservation of coding potential and terminal sequences in four different isolates of Borna disease virus.

We determined the complete nucleotide sequences of two poorly characterized strains of Borna disease virus (BDV) and compared them to reference strains V and He/80. Strain H1766 was almost 98% and 95% identical to strains V and He/80, respectively, whereas strain No/98 was only about 81% identical to both reference strains. In contrast to earlier reports, we found an additional A residue at the extreme 3'-end of the single-stranded RNA genome in all four BDV strains. The exact numbers of nucleotides in the four BDV genomes could not be determined due to a micro-heterogeneity at the 5'-end. If our longest sequence is a correct copy of the viral RNA, the two ends of the BDV genome would show almost perfect complementarity. All three transcription start sites, all four termination sites, both splice donor sites and both major splice acceptor sites are highly conserved, whereas a minor alternative splice acceptor site is not. The L protein of No/98 differs at 7% of its amino acid positions from the polymerase in the other strains, with most differences mapping to the C-terminal moiety of the molecule. Re-evaluation of L protein sequences of strains V and He/80 revealed differences at several positions compared to published information, indicating that variant forms of the viral polymerase have previously been characterized. These results are important because correct structures of genome ends and of the polymerase gene are the most critical parameters for the future development of techniques that will permit the genetic manipulation of BDV.

3' Untranslated Regions↗

PubMedDate not supplied

Use of an internal standard in a closed one-tube RT-PCR for the detection of equine arteritis virus RNA with fluorescent probes.

Routine detection of equine arteritis virus (EAV) can be achieved by virus isolation (VI) in cell culture, or by the amplification of viral genome by molecular methods. To simplify molecular diagnosis, a number of different Reverse Transcriptase Polymerase Chain Reaction (RT-PCR) and RT-nested PCR (RT-nPCR) assays were compared, and a one-tube method was developed and optimised utilizing a fluorogenic probe (TaqMan). An artificial RNA template (Mimic) and associated probe were also constructed to provide in-tube validation of the RT-PCR system. To assess the utility of the RT-PCR TaqMan assay, 28 different isolates of EAV representing different genetic groups of American and European strains were tested. Furthermore, the ability of VI and RT-PCR TaqMan assay to detect EAV in different biological matrices such as semen, nasal and faecal swabs and blood was compared. All 28 EAV strains were detected by the RT-PCR TaqMan assay. The results of TaqMan and VI testing were in agreement for 30 of the 33 semen samples and all of the 50 other clinical specimens examined: the RT-PCR TaqMan assay detected 18 positive semen samples, three more than VI. In conclusion, the one-tube RT-PCR TaqMan assay is a rapid, reliable method for the detection of EAV.

Animals↗

PubMedDate not supplied

[Seroepidemiological studies of zoonotic infections in hunters in southeastern Austria--prevalences, risk factors, and preventive methods].

The aim of this study was to investigate the seroprevalences to zoonotic pathogens in hunters, to propose preventive measures and to obtain more information about the occurrence of zoonotic pathogens in local wild animal populations. From 146 male and 3 female hunters originating from the south-eastern Austrian federal states of Styria and Burgenland blood samples were taken and anamnestic data were obtained using a questionnaire. The serological investigations included the following viral, bacterial and parasitic zoonotic agents or zoonoses, respectively (antibody-seroprevalences in brackets): encephalomyocarditis virus (EMCV, 15%), Puumala-Hantavirus (10%), Newcastle Disease virus (NDV, 4%), borreliosis (IgG 42%, IgM 7%), brucellosis (1%), chlamydiosis (3%), ehrlichiosis (IgG 15%, IgM 3%), leptospirosis (10%), tularaemia (3%), Q fever (0%), Echinococcus multilocularis/E. granulosus (5%/11%), toxocariasis (17%). Out of a control group of 50 persons (urban population, no hunters) only one person was found to be seropositive for Toxocara canis and NDV and four for EMCV, all other results were negative in the control group. The high seroprevalences especially to Borrelia burgdorferi s.l., Ehrlichia spp., Leptospira interrogans, E. granulosus, E. multilocularis, encephalomyocarditis virus and Puumala virus demonstrate that hunters are particularly exposed to zoonotic pathogens. It should also be noted that one hunter was seropositive for Brucella abortus and five exhibited antibodies to Francisella tularensis. In these cases, as well as in the cases of the 15 seropositives for Leptospira interrogans, the suspected source of infection may--besides rodents--also include wild boars and brown hares. The infections with NDV and Chlamydophila psittaci may be traced back to contact with certain species of birds (potential risk: aviaries). For Hantaviruses, rodents are considered to be the main source of human infections.

Animals↗

PubMedDate not supplied

[Screening for antibodies against zoonotic agents among employees of the Zoological Garden of Vienna, Schönbrunn, Austria].

The aim of this study was to investigate the prevalence of antibodies against zoonotic agents in employees of the zoological garden of Vienna, Schönbrunn, Austria. Sixty out of 120 employees participated in the study. In 97% of them antibodies to at least one zoonotic agent were identified. Only two participants were free of antibodies to the zoonotic agents tested. The following seroprevalences (in brackets) were obtained: Viral zoonotic (and potentially zoonotic) agents: Influenzavirus A/H1N1 (58%), Influenzavirus A/H3N2 (85%), Lymphocytic choriomeningitis virus (13%), Encephalomyocarditis virus (5%), Orthopox- (Cowpox-) virus and Hantavirus type Puumala (3%). Hantavirus type Hantaan and Borna disease virus (all negative). Bacterial zoonotic agents: Bartonella henselae (65 %), Borrelia burgdorferi (10%), Leptospira interrogans serovar copenhageni and serovar icterohaemorrhagiae as well as Chlamydophila psittoci (2% each). Brucella spp., Coxiella bumetii, and Francisella tularensis (all negative). Parasitic zoonotic agents: Toxoplasma gondii (53%), Toxocara spp. (21%), Capillaria hepatica (2%), Fasciola hepatica, Schistosoma mansoni, E. multilocularis, and E. granulosus (all negative). The remarkably high seroprevalence to the causative agent of cat scratch disease, Bartonella henselae, is probably due to the private contact of the employees to cats. Regarding viral zoonotic agents it has to be mentioned that Influenzavirus vaccination and/or human-to-human transmission of especially A/H3N2 Influenzaviruses probably attributed significantly to the very high seroprevalence to both Influenzavirus types A/H1N1 and A/H3N2. When investigating parasitic zoonotic agents, high prevalence rates were found against Toxoplasma gondii and Toxocara spp., however, it was not possible to establish a causal link between seropositivity and the professional activity in the zoo. Interestingly, in the case of antibodies to T. gondii, the typical correlation with age was not found in this study, while in the case of the Toxocara spp. positive subjects a correlation was identified with both age and duration of employment in the zoo. Regarding the later two zoonotic parasites, employees of the zoological garden showed significantly higher seroprevalences than the average Austrian population. Antibodies to Capillaria hepatica, a hepatic-parasite in rodents which is diagnosed in humans rarely, were identified in one employee and another one showed a questionable positive result. Further investigations did not exhibit clinical infestations with the parasite in these two individuals so far.

Adolescent↗