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A Schwandt

Publications and source records attributed to A Schwandt.

6 recordsLinked to original sources
PubMed2001

Prospective analysis of a fever evaluation algorithm after major gynecologic surgery.

OBJECTIVE: We performed a prospective trial to evaluate the feasibility, accuracy, and safety of a postoperative fever algorithm that is based on symptoms and physical examination in an attempt to decrease the random use of urine cultures, blood cultures, and chest radiographs. STUDY DESIGN: Our fever algorithm consisted of assessing all febrile postoperative patients for signs and symptoms of infection. If none were present, no tests were ordered. RESULTS: Twenty-eight of 105 consecutive patients (27%) had postoperative fever after major gynecologic surgery. Three of 28 febrile patients (11%) were evaluated with tests according to the algorithm. Two of 28 febrile patients (7%) were evaluated in violation of the algorithm. Four febrile patients (14%) had documented infections. Two patients had infections within the first 30 days after discharge. Compared with our previous retrospective review, significantly fewer febrile patients were evaluated with testing with a significantly increased yield of positive test results. CONCLUSIONS: Our postoperative fever evaluation algorithm that is based on symptoms and physical examination is feasible, is safe, decreases random testing, and increases the yield of positive test results.

Adult↗
PubMed1999

Experiences in HCV-NAT screening prior to releasing cellular components by the German Red Cross Blood Transfusion Service of Baden-Württemberg.

In this report we present the accumulated data on nucleic acid testing (NAT) for hepatitis C virus (HCV) RNA of blood donations by the Blood Transfusion Service of Baden-Württemberg in the period between March 1997 and March 1999. An extra barcoded blood sample was collected from each donor. Samples were tested by NAT in mini-pools of maximally 96 samples. First-time and repeat donors were tested separately. RT/HCV-PCR was performed with the COBAS HCV Amplicortrade mark, versions 1.0 and 2.0 from Roche Diagnostic Systems. Many modifications have been introduced to the original protocol since the implementation of NAT screening aiming at an increase in the sensitivity and specificity of the assay. NAT positive pools containing serologically positive samples were detected. Initially, reactive pools were identified that could not be confirmed by secondary pooling and single testing procedures. So far, no serologically negative but NAT positive sample has been found.

Blood Banks↗
PubMed1998

Human Langerhans cells express a novel form of the leukocyte common antigen (CD45).

CD45 is a family of transmembrane glycoproteins that function as protein tyrosine phosphatases. All isoforms exhibit common CD45 epitopes, whereas the restricted CD45 epitopes (RA, RB, and RO) are each limited to one or more isoforms. In prior studies, we showed that human Langerhans cells in normal epidermis express a novel CD45 phenotype. They express common CD45 epitopes but are characteristically RA- RB- RO-. This suggests that Langerhans cells can express a novel form of CD45. In order to clarify this issue further, mRNA extracted from enriched Langerhans cell preparations was reverse transcribed into cDNA. The 5' portion of CD45 cDNA was then amplified using polymerase chain reaction primers complementary to exon 2 and exons 9-10, which flank the CD45 variable exon region (exons 4-6). Cloning and sequencing of the dominant 441 bp polymerase chain reaction product revealed the following exon configuration for the 5' translated region of Langerhans cells CD45: exon 3/7/8/9/10. This is the same exon configuration associated with the 180 kd CD45 isoform expressed by memory T cells and monocytes/macrophages; however, these cell types are RO+ whereas normal Langerhans cells are RO-. The RO epitope is known to be an oligosaccharide with a terminal sialic acid moiety. Therefore, we determined the expression of a related epitope, OPD4, by Langerhans cells. This is another terminal sialic acid moiety expressed by the 180 kd CD45 isoform of memory T cells but not by monocytes/macrophages. Langerhans cells were OPD4-. Our data suggest that memory T cells, monocytes/macrophages, and Langerhans cells all express a common CD45 transcript lacking exons 4-6; however, this transcript appears to undergo lineage-specific, post-translational glycosylation to create three distinct CD45 glycoproteins: RO+ OPD4+, RO+ OPD4-, and RO- OPD4-, which are expressed typically by memory T cells, monocytes/macrophages, and Langerhans cells, respectively. Because these epitopes are located extracellularly, they are postulated to allow differential responses to extracellular stimuli by creating differential ligand specificity.

Epitopes↗
PubMedDate not supplied

A temperature-sensitive mutation affecting synthesis of outer arm dyneins in Tetrahymena thermophila.

We have characterized a novel, temperature-sensitive mutation affecting motility in Tetrahymena thermophila. Mutants grew and divided normally at the restrictive temperature (38 degrees C), but became nonmotile. Scanning electron microscopic analysis indicated that nonmotile mutants contained the normal number of cilia and that the cilia were of normal length. Transmission electron microscopic analysis indicated that axonemes isolated from nonmotile mutants lacked outer dynein arms, so the mutation was named oad 1 (outer arm deficient). Motile mutants shifted to 38 degrees C under conditions that prevent cell growth and division (starvation) remained motile suggesting that once assembled into axonemes at the permissive temperature (28 degrees C) the outer arm dyneins remain functional at 38 degrees C. Starved, deciliated mutants regenerated a full complement of functional cilia at 38 degrees C, indicating that the mechanism that incorporates the outer arm dynein into developing axonemes is not affected by the oad 1 mutation. Starved, nonmotile mutants regained motility when shifted back to 28 degrees C, but not when incubated with cycloheximide. We interpret these results to rule out the hypothesis that the oad 1 mutation affects the site on the microtubules to which the outer arm dyneins bind. Axonemes isolated from mutants grown for one generation at 38 degrees C had a mean of 6.0 outer arm dyneins, and axonemes isolated from mutants grown for two generations at 38 degrees C had a mean of 3.2 outer arm dyneins. Taken together, these results indicate that the oad 1 mutation affects the synthesis of outer arm dyneins in Tetrahymena.

Animals↗
PubMedDate not supplied

Biochemical analysis of a mutant Tetrahymena lacking outer dynein arms.

Tetrahymena thermophila mutants homozygous for the oad mutation become nonmotile when grown at the restrictive temperature, and axonemes isolated from nonmotile mutants lack approximately 90% of their outer dynein arms. Electrophoretic analyses of axonemes isolated from nonmotile mutants (oad axonemes) indicate they contain significantly fewer of the 22 S dynein heavy chains that axonemes isolated from wild-type cells (wild-type axonemes) contain. The 22 S dynein heavy chains that remain in axonemes isolated from nonmotile, oad mutants are assembled into 22 S dynein particles that exhibit wild-type levels of ATPase activity. Two-dimensional gel electrophoresis of oad axonemes show that they are deficient in no proteins other than those proteins thought to be components of 22 S dynein. This report is the first formal proof that outer dynein arms in Tetrahymena cilia are composed of 22 S dynein.

Animals↗