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B Ludwig

Publications and source records attributed to B Ludwig.

At least 109 records · Page 6Linked to original sources
PubMed1991

Cloning, genetic analysis, and nucleotide sequence of a determinant coding for a 19-kilodalton peptidoglycan-associated protein (Ppl) of Legionella pneumophila.

A genomic library of Legionella pneumophila, the causative agent of Legionnaires disease in humans, was constructed in Escherichia coli K-12, and the recombinant clones were screened by immuno-colony blots with an antiserum raised against heat-killed L. pneumophila. Twenty-three clones coding for a Legionella-specific protein of 19 kDa were isolated. The 19-kDa protein, which represents an outer membrane protein, was found to be associated with the peptidoglycan layer both in L. pneumophila and in the recombinant E. coli clones. This was shown by electrophoresis and Western immunoblot analysis of bacterial cell membrane fractions with a monospecific polyclonal 19-kDa protein-specific antiserum. The protein was termed peptidoglycan-associated protein of L. pneumophila (Ppl). The corresponding genetic determinant, ppl, was subcloned on a 1.8-kb ClaI fragment. DNA sequence studies revealed that two open reading frames, pplA and pplB, coding for putative proteins of 18.9 and 16.8 kDa, respectively, were located on the ClaI fragment. Exonuclease III digestion studies confirmed that pplA is the gene coding for the peptidoglycan-associated 19-kDa protein of L. pneumophila. The amino acid sequence of PplA exhibits a high degree of homology to the sequences of the Pal lipoproteins of E. coli K-12 and Haemophilus influenzae.

Amino Acid Sequence↗
PubMed1991

[Hydrophobicity and microbial production. 1. Selection of oleophilic microorganisms and qualitative characterization by several ecologically and technologically relevant activities].

From samples of different origin microorganisms were selected using the property of oleophily. All oleophilic isolates (30 strains are characterized in more detail) proved to be Gram-positive, nonsporogenic bacteria, obviously belonging to the group of coryneforms. They are growing on a broad spectrum of substrates, 11 strains are facultatively methylotrophic. They are utilizing methanol as well as n-alkanes and glucose without any supplines. 6 strains are able to degrade and decolorize triphenylmethane dyes, for example crystal violet and malachite green. Because of the degradative capacities, combined with the hydrophobic properties of the cell surface, the group of the oleophilic bacteria seems to be very promising in relation to the development of environmental technologies and ecological investigations.

Actinomycetales↗
PubMed1990

Cerebral and spinal MR-findings in patients with postrepair myelomeningocele.

In 114 patients with postrepair myelomeningocele MRI of the spine was performed. Tethered cord (89%) and associated malformations (syrinx, lipoma etc.) (33%) were the most important findings. Additional MRI scans of the head (44 patients) revealed numerous further anomalies. Arnold Chiari malformation was found in 76% of the patients (ACM I:32%, ACM II:44%). In the ACM II group compression of lower cranial nerves, brain stem, and cerebellum can lead to considerable neurologic symptoms. Therefore in patients with progressive neurologic dysfunction a complete investigation of the whole spine and brain is necessary. MRI proves to be the diagnostic procedure of choice in patients with dysraphic myelodysplasia.

Adolescent↗
PubMed1990

Complete genetic organization and functional aspects of the Escherichia coli S fimbrial adhesion determinant: nucleotide sequence of the genes sfa B, C, D, E, F.

The S fimbrial adhesin (sfa) determinant of E. coli comprises nine genes situated on a stretch of 7.9 kilobases (kb) DNA. Here the nucleotide sequence of the genes sfa B and sfa C situated proximal to the main structural gene sfaA is described. Sfa-LacZ fusions show that the two genes are transcribed in opposite directions. The isolation of mutants in the proximal region of the sfa gene cluster, the construction of sfa-phoA gene fusions and subsequent transcomplementation studies indicated that the genes sfa B and sfa C play a role in regulation of the sfa determinant. In addition the nucleotide sequence of the genes sfa D, sfa E and sfa F situated between the genes sfa A and sfa G responsible for S subunit proteins, were determined. It is suggested that these genes are involved in transport and assembly of fimbrial subunits. Thus the entire genetic organization of the sfa determinant is presented and compared with the gene clusters coding for P fimbriae (pap), F1C fimbriae (foc) and type I fimbriae (fim). The evolutionary relationship of fimbrial adhesion determinants is discussed.

Adhesins, Escherichia coli↗
PubMed1990

Primary leiomyosarcoma of the truncus pulmonalis. Report of a case with typical features and unusual metastases.

We present the fatal case of a patient with a primary leiomyosarcoma of the pulmonary trunk. During the patient's clinical course of 2 months, the pulmonary valve and the proximal segment of the truncus pulmonalis had to be removed surgically. At autopsy, we found an extensive local tumour recurrence with an almost complete obliteration of the right ventricular outflow. The right pulmonary artery was subtotally obliterated by a tumour thrombus, and the lungs and both adrenal glands showed extensive tumour metastases. A solitary tumour metastasis within the lumen of the right vena iliaca communis obviously was associated with diagnostic manipulations in the course of heart catheterization.

Blood Vessel Prosthesis↗
PubMed1990

Plasma disposition and tolerance of aditoprim in horses after single intravenous injection.

Aditoprim, a broad spectrum antimicrobial agent acting as a reversible dihydrofolate reductase inhibitor, was intravenously injected into four 12 to 24-year old horses at a dosage of 5 mg/kg b. w. Blood samples were collected over a 48-hour period after drug injection, and the separated plasma samples were assayed for aditoprim by high performance liquid chromatography. The body temperature, heart rate, respiration rate, and behaviour were recorded during the experiment. The bilirubin and urea concentrations were also determined in several plasma samples, and liver function tests were carried out. The concentrations of aditoprim in the plasma of horses were higher than the MIC of this drug against recently isolated pathogens for 6-13 h (Pasteurella haemolytica A 1) to 48 h (E. coli). The main pharmacokinetic characteristics of aditoprim in horses were: a large volume of distribution, reaching a mean value of 7.8 l/kg; a mean plasma clearance of 5.0 l/min; a plasma elimination half-life of 12 h. The clinical observations, blood chemistry, and liver function tests all demonstrated that the drug was well tolerated by the horses, although it was injected intravenously as a 25% solution. It was concluded that the 25% aditoprim injection solution could be used in horses without adverse effects at 5 mg/kg. Furthermore, aditoprim should demonstrate good antibacterial effects in horses when intravenously injected once a day.

Animals↗
PubMed1990

Paracoccus denitrificans cytochrome c1 gene replacement mutants.

We describe the construction and characterization of gene replacement mutants for the respiratory chain component cytochrome c1 in the bacterium Paracoccus denitrificans. Its structural gene (fbcC) was inactivated by insertion of the kanamycin resistance gene, introduced into a suicide vector, and conjugated into Paracoccus; chromosomal mutants obtained by homologous recombination were selected by antibiotic resistance screening and further characterized biochemically. They showed the complete spectral, enzymatic, and immunological loss of the fbcC gene product together with a serious defect in the assembly of the two other gene products of the fbc operon, cytochrome b and the FeS protein. A possible role of the cytochrome c1 in the assembly process for the enzyme complex is discussed. A functional restoration to wild-type phenotype was achieved by complementing in trans with a newly constructed broad-host-range vector carrying the fbcC gene cassette. When the complete fbc operon was present on this vector, overexpression of complex III subunits was observed. Apart from their physiological significance, such mutants are a prerequisite for probing structure-function relationships by site-directed mutagenesis in order to understand molecular details of electron transport and energy transduction processes of this respiratory enzyme in bacteria and in mitochondria.

Blotting, Southern↗
PubMed1989

Sulotroban during and after coronary angioplasty. A double-blind, placebo controlled study.

Sulotroban, a sulphonamide derivative, causes an inhibition of platelet aggregation by blocking thromboxane A2 receptors. We tested the effects of Sulotroban (4 x 800 mg per day) on acute events during and recurrence rate after coronary angioplasty, and compared it with placebo in a double-blind randomized fashion. The follow-up protocol included regular compliance control by pill count, stress testing, and coronary angiography at 6 months. Restenosis was defined as a loss of 50% of the initial gain in luminal diameter. A total of 107 patients were randomized. There were no differences between the groups in terms of age, sex, artery distribution, or left ventricular function. Primary success per vessel was 86% for the Sulotroban group (50/58), and 88% for the placebo group (51/58). Complications occurred in nine patients (8%): five emergency bypass operations and three myocardial infarctions. There were no differences between the centers, or the study groups. The study protocol was completed for 57 patients. There was one death in the placebo group. Restenosis was found in 65% of patients in the Sulotroban group (19/29) and 61% of patients in the placebo group (17/28) (ns). If all patients were included on an intention to treat basis, regardless of primary success and compliance with the protocol, the recurrence rate was 57% in the Sulotroban group (20/35), compared with 56% in the Placebo group (20/36) (ns). This randomized, double-blind study failed to show that Sulotroban is superior to placebo in preventing acute problems during, or restenosis after, coronary angioplasty.

Angioplasty, Balloon↗
PubMed1989

Use of pharmacokinetics when dealing with the drug residue problem in food-producing animals.

If the principal pharmacokinetic parameters of a veterinary drug-such as its elimination half-life from blood plasma, volume of distribution, plasma protein binding and metabolism-are known, then the presence and concentration of residues in animal tissue after administration of the drug can be predicted. This makes it possible to reduce the number of animals required by conventional residue testing and satisfies a legitimate demand of animal welfare groups. Using radioactively labelled drugs, the ratio of the parent substance to its metabolites can be established. Thus as a rule the determination of parent substance is sufficient for the routine determination of residues in foodstuffs. This is true in particular of sulfonamides. The pharmacokinetics of this class of substances are such that their main metabolites are eliminated from the animal's body faster than the parent substance. Other examples given are ceftriaxone, carprofen und climazolam.

Animals↗
PubMed1989

Carprofen in veterinary medicine. II. Inhibitory effect on the release of PGF2 alpha in the early postpartum cow.

Carprofen, a non-steroidal anti-inflammatory drug (NSAID) known to inhibit prostaglandin synthesis, was given intravenously in five cows at a daily dose of 0.7 mg/kg for five days beginning on day 1 postpartum. Blood samples were collected at various times over a period of six days following the first injection. At this dose, carprofen reached highest plasma values of about 45 micrograms/ml after the fifth injection and was well tolerated by all the cows. During the whole experimental period, mean plasma levels of 15-keto-13, 14-dihydro-prostaglandin F2 alpha, the primary metabolite of PGF2 alpha, were significantly (p less than 0.05) lower in treated than in control animals (28-47% vs 64-101% of pretreatment concentrations). The suppressive effect of carprofen on PGF2 alpha-production occurred immediately after its application and was maximal 3-6 h post injection on the first and on the fifth experimental day (60-80% and 40-85%, respectively). We conclude from our results that carprofen in a single dose of 0.7 mg/kg b.w. effectively suppresses PGF2 alpha-release in the postpartum cow. Whether this effect is beneficial in the treatment of uterine inflammatory processes remains to be determined.

Animals↗
PubMed1989

Carprofen in veterinary medicine. I. Plasma disposition, milk excretion and tolerance in milk-producing cows.

Carprofen, a non-steroidal anti-inflammatory drug (NSAID), was injected intravenously in six cows after calving, either as a single or a daily dose of 0.7 mg/kg for five days. Carprofen was well tolerated by the cows at this dose rate, the milk production and biochemical variables remaining within the normal ranges. The plasma elimination half-life of carprofen ranged from 44.5 to 64.6 h after repeated daily injections. These values are longer than those reported for other NSAIDs used in veterinary medicine, e.g. flunixin and phenylbutazone. The volume of distribution and the clearance values calculated after a single intravenous injection amounted to 0.09 l/kg and 9.0 ml/min. The concentration of carprofen in milk collected twice daily (morning and evening) was, in general, below the sensitivity limit of the analytical method (25 ng/ml) up to five days after the last carprofen injection; the concentration of carprofen reached about 30 ng/ml in only a few milk samples collected after the fourth or fifth injection. This indicates that carprofen is poorly excreted in the milk.

Animals↗
PubMed1988

Assessment of indapamide in elderly hypertensive patients with special emphasis on well-being.

One hundred forty-nine patients between 56 and 80 years of age with mild to moderate hypertension received indapamide (2.5 mg per day) monotherapy for 12 weeks. In addition to studies of the efficacy and tolerance of indapamide, the study comprised an assessment of well-being, which was carried out objectively by the physician, and subjectively by the patient himself, by means of a list of complaints and a visual analogue scale. The mean blood pressure was lowered from 179/91 mm Hg (supine) before treatment to 149/81 mm Hg at the end of the treatment. The general well-being of the patients, as judged by the physician, showed a markedly positive evolution. The patients themselves indicated that their most frequent symptoms, such as sleep disorders, functional organic disturbances, and sensory and motor fatigue, had improved by 65 to 85 percent, indicating a tendency to better compliance.

Aged↗