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W Rüger

Publications and source records attributed to W Rüger.

At least 37 records · Page 2Linked to original sources
PubMed1993

Characterization of cDNA clones encoding a major microneme antigen of Sarcocystis muris (Apicomplexa) cyst merozoites.

Two monoclonal antibodies directed against a microneme antigen of Sarcocystis muris cyst merozoites (16/17 kDa band doublet) were used to isolate cDNA clones from a lambda ZAP expression library. Restriction analysis revealed that the inserts were highly similar, with sizes ranging between 1.8 and 2.3 kb. In addition, a full-length cDNA insert of 2.6 kb was obtained by hybridization screening. On Northern blots, a single mRNA species of 2.7 kb was detected by a cDNA-derived probe. Southern blot hybridization suggests that the gene is present as a single copy. The nucleotide sequence of the full-length clone contains a single reading frame with a coding capacity of 26.5 kDa. The hypothetical polypeptide consists of a putative N-terminal signal peptide followed by a hydrophilic domain of unknown function, and the mature protein sequence. After purifying the 16/17 kDa antigen from cyst merozoites, a partial N-terminal amino acid sequence was obtained. Thus, the identity of the cDNA sequence was confirmed. The deduced sequence of the mature protein is predominantly hydrophilic and rich in cysteine (8.7%). Database searching suggested weak homologies of the hypothetical polypeptide to plasma kallikrein, tenascin and blood coagulation factors.

Amino Acid Sequence↗
PubMed1992

A comparison of sporozoite and cyst merozoite surface proteins of Sarcocystis.

Surface labeling of Sarcocystis muris and S. suicanis sporozoites with N-hydroxysuccinimide biotin led to the detection of major membrane proteins with relative molecular weights of 29 and 30 kDa, respectively. Immunoblots of Sarcocystis sporozoite proteins probed with sera from infected hosts or with polyclonal monospecific antibodies generated against membrane antigens of cyst merozoites (noncorresponding stages) showed cross-reactivity between the two developmental stages (cyst merozoites and sporozoites) as well as between the species S. muris and S. suicanis. Two-dimensional gel electrophoresis resulted in the identification of isoforms of the sporozoite membrane antigens, with isoelectric points ranging from pH 4.7 to pH 6.4 for S. muris and from pH 4.7 to pH 5.2 for S. suicanis. The molecular masses, the charge heterogeneity, and the immunological reactivity of the surface proteins of Sarcocystis sporozoites were similar to those of cyst merozoites of both species.

Animals↗
PubMed1992

Deoxyuridylate-hydroxymethylase of bacteriophage SPO1.

Phage SPO1 of Bacillus subtilis carries hydroxymethyl-deoxyuridylate in place of thymidylate in its DNA. The enzyme, responsible for the conversion of dUMP to HmdUMP, is a dUMP hydroxymethylase, encoded by the SPO1 gene 29. Here we describe the cloning and sequencing of the gene and the overexpression of the gene product. DNA hybridization using the DNA of bacteriophage T4 dCMP-hydroxymethylase gene as a probe, allowed us to identify and map g29 on a 3.9-kb restriction fragment, EcoRI*11. We determined the nucleotide sequence. One of the open reading frames detected, coding for a putative 44.6-kDa protein, showed significant amino acid homologies with all known thymidylate synthases. Gp29 was overexpressed in the pT7 system. Extracts prepared from induced cells show hydroxymethylase activity in a tritium release assay.

Amino Acid Sequence↗
PubMed1992

Cloning and expression in Escherichia coli of cDNAs encoding a 31-kilodalton surface antigen of Sarcocystis muris.

Using polyadenylated RNA isolated from Sarcocystis muris cyst merozoites, we have constructed a cDNA library in the expression vector lambda ZAP. Immunoscreening with monoclonal and polyclonal antibodies directed against a 31-kDa surface antigen of S. muris [1] yielded a number of clones with insert sizes ranging between 1.1 kb and 1.3 kb. An additional clone with an insert length of 1.55 kb was isolated by screening with a labeled DNA probe derived from one of the cDNA clones. The cDNA sequence was found to contain an open reading frame specifying a polypeptide of 280 amino acids with a predicted size of 29.7 kDa. The deduced amino acid sequence is rich in serine and threonine (22%) and harbors a hypothetical N-terminal signal peptide sequence as well as a C-terminal glycosyl phosphatidylinositol anchor attachment site. The predicted amino acid sequence has been confirmed by peptide sequencing and an analysis of the overall amino acid composition of the 31-kDa protein. A recombinant protein was obtained which was recognized by the polyclonal antibodies directed against the 31-kDa antigen. Antiserum raised against the purified fusion protein specifically reacted with a 31-kDa protein from S. muris cystozoites. Southern blot analysis indicated that the corresponding gene exists as a single copy within the S. muris genome.

Amino Acid Sequence↗
PubMed1992

The Vienna SMZO-PACS-project: the totally digital hospital.

This paper gives an overview of the SMZO-PACS-Project in the form of a rough specification of the system architecture and the functional parameters related to it. The PACS architecture, determined by the large amount of data volume produced in the SMZO Hospital is outlined. In both radiology and trauma departments high technical requirements concerning data throughout and fault tolerance are demanded. Therefore these PACS modules are designed to minimize the workload of the network so that the performance is not degraded in the case of fault of a single component. A PACS module includes image acquisition devices of a certain modality with related reporting workstations and a distributed electronic archive. The functionality of the modules is described, special interest is posed on the integration of the different information management systems PACS, RIS and HIS, to achieve a complete record of data input and throughput in the hospital.

Austria↗
PubMed1992

Integration of radiology and hospital information systems (RIS, HIS) with PACS: requirements of the radiologist.

PACS development has now reached a stage where it can clearly be stated that the technology for storage, networking and display in a fully digital environment is available. This is reflected by an already large and rapidly increasing number of PACS installations in USA, Western Europe and Japan. Such installations consist of a great variety of information systems, more or less interconnected, like PACS, HIS, RIS and other departmental systems, differing in both hardware and software. Various data - even if they only concern one person - are stored in different systems distributed in the hospital. The integration of all digital systems into a functional unit is determined by the radiologist's need of quick access to all relevant information regardless where it is stored. The interconnection and functional integration of all digital systems in the hospital determine the clinical benefits of PACS. This paper (1) describes the radiologist's requirements concerning this integration, and (2) presents some realistic solutions such as the Siemens ISI (Information System Interface), and a mobile viewing station for the wards (visitBox).

Austria↗
PubMed1991

Gene product dsbA of bacteriophage T4 binds to late promoters and enhances late transcription.

Gene product 33 of phage T4 is known to be essential in late transcription. Upstream from gene 33 and overlapping its 5' terminal sequence by 20 bp, we identified an open reading frame coding for a binding protein for double-stranded DNA (DsbA). Gene product DsbA is composed of 89 amino acid residues with a Mr of 10376 kDa. We purified this protein to homogeneity from over-expressing cells. Gel retardation assays reveal that it binds to DNA and footprint analyses disclose that it interacts preferentially with T4 late promoter regions. At the sites of binding the protein introduces nicks in double-stranded DNA. In vitro transcription assays performed with T4 late modified RNA polymerase on restriction fragments harbouring a T4 late promoter region prove that gene product DsbA enhances transcription from these promoter regions in the presence of gene product 33. Gene dsbA is distinct from gene das which maps close to this genomic region.

Base Sequence↗
PubMed1991

Biochemical and immunological characterization of major surface antigens of Sarcocystis muris and S. suicanis cyst merozoites.

Surface proteins of Sarcocystis cyst merozoites were labeled by biotinylation or radioiodination and identified on Western blots after sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE). The major labeled proteins of S. muris and S. suicanis have relative molecular masses of 31 and 33 kDa, respectively. Immunoblots performed with the 31-kDa protein and sera of experimentally infected mice or with monoclonal antibodies to S. muris revealed that this protein is immunogenic. Indirect fluorescent antibody tests (IFAT) executed using Sarcocystis cyst merozoites and polyclonal monospecific antibodies obtained from rabbits immunized with homogeneous major surface antigens gave additional evidence for the localization of the identified antigens in the pellicle. Analysis of S. muris and S. suicanis proteins by two-dimensional gel electrophoresis revealed multiple isoelectric forms.

Animals↗
PubMed1990

[Longitudinal study of the denture condition of young people between the age of 16 and 18].

Medical evidence on the extension and progression tendency of caries and periodontal diseases have been made by OHI/S, DMF/T-index as well as CPITN with the help of 555 apprentices at the beginning of their vocational training. Shortly before finishing their apprenticeship 415 of then had been examined again in the course of which had to be find out how their teeth-formation had worsened according to periodic examination within 18 month. The results show a clear deterioration of the oral state of health, but evidently indicate that corrections can be gained by continuous care, prevention and early diagnosis.

Adolescent↗
PubMed1989

Effects of the novel compound, Hoe 065, upon impaired learning and memory in rodents.

The effects of Hoe 065 (n-octyl 2-[N-[(S)-1-ethoxycarbonyl-3-phenylpropyl]-L-alanyl]-(1S,3S, 5S)-2-azabicyclo [3.3.0]octane-3-carboxylate maleate salt) were studied on the performance of mice and rats in different learning tasks. Hoe 065 prevented the disruption of memory induced by scopolamine administered before training. The results indicate that Hoe 065 improves cognitive function in different tasks.

Animals↗
PubMed1989

Bacteriophage T4 early promoter regions. Consensus sequences of promoters and ribosome-binding sites.

Twenty-nine early promoters from bacteriophage T4 and 14 early promoters from bacteriophage T6 were isolated using vector M13HDL17, a promoterless derivative of M13mp8 carrying a linker sequence, the bacteriophage lambda-terminator tR1, and the lacZ' gene including part of its ribosome-binding site. The consensus sequence for the T4 promoters is: (sequence; see text). Ribosome-binding sites of T4 share the sequence: 5'...g.GGAga..aA.ATGAa.a...3' The consensus sequence of the T4 early promoter regions is significantly different in sequence and length from that of Escherichia coli promoters. Only one of the promoters detected with vector M13HDL17 resembled a typical bacterial promoter. The high information content raises the possibility that additional proteins recognize and contact nucleotides within the promoter region. All T4 early promoters also carry DNA sequences that could support DNA curving, a structural feature that might contribute to promoter recognition.

Base Sequence↗
PubMed1989

Effects of Hoe 065, a compound structurally related to inhibitors of angiotensin converting enzyme, on acetylcholine metabolism in rat brain.

Hoe 065, a compound structurally related to inhibitors of angiotensin converting enzyme, caused a fall in the content of acetylcholine (ACh) in different brain areas of the rat following i.p. administration in the range 0.03-30 mg/kg. This effect occurred 0.5 h after a single injection and lasted for at least 6 h. Simultaneous administration of the choline uptake inhibitor hemicholinium-3 (HC-3) with Hoe 065 potentiated the decrease in ACh content induced by HC-3. In the same dose range Hoe 065 acutely enhanced the activity of the enzyme choline acetyltransferase as well as the capacity of the high-affinity choline uptake system which is considered as the rate-limiting step in the synthesis of ACh. Cholinesterase activity in vivo was not altered by the compound. Hoe 065 produced a concurrent elevation of brain cyclic GMP content. Taken together, these results suggest that Hoe 065 acutely increases cholinergic activity within its physiological range, probably by means of an enhanced release of ACh.

Acetylcholine↗
PubMed1989

The inconsistent distribution of introns in the T-even phages indicates recent genetic exchanges.

Group I self-splicing introns are present in the td, nrdB and sunY genes of bacteriophage T4. We previously reported that whereas the td intron is present in T2, T4 and T6, the nrdB intron is present in T4 only. These studies, which argue in favor of introns as mobile genetic elements, have been extended by defining the distribution of all three T4 introns in a more comprehensive collection of T2, T4 and T6 isolates. The three major findings are as follows: First, all three introns are inconsistently distributed throughout the T-even phage family. Second, different T2 isolates have different intron complements, with T2H and T2L having no detectable introns. Third, the intron open reading frames are inherited or lost as a unit with their respective flanking intron core elements. Furthermore, exon sequences flanking sites where introns are inserted in the T4 td, sunY and nrdB genes were determined for all the different T-even isolates studied. Six of eighteen residues surrounding the junction sequences are identical. In contrast, a comprehensive comparison of exon sequences in intron plus and intron minus variants of the sunY gene indicate that sequence changes are concentrated around the site of intron occurrence. This apparent paradox may be resolved by hypothesizing that the recombination events responsible for intron acquisition or loss require a consensus sequence, while these same events result in sequence heterogeneity around the site.

Base Sequence↗