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H Lode

Publications and source records attributed to H Lode.

At least 127 records · Page 7Linked to original sources
PubMed1994

Comparative pharmacokinetics of the new oral cephalosporins.

The comparative pharmacokinetics of the new oral cephalosporins (ester and nonester types), together with that of the first generation carbacephem, loracarbef, are considered in healthy volunteers. Also in this review, pharmacokinetic and microbiological data are combined in order to predict the possible clinical efficacy of this group of agents. Despite apparent similarities in the structure of these agents, single dose studies have revealed marked differences in the pharmacokinetics of the oral cephalosporins. Multiple dose studies showed no evidence of accumulation with these agents. In the elderly, only minor changes in the pharmacokinetics of the oral agents were observed, and were insufficient to warrant dosage adjustment. Unlike that of the nonester compounds, the bioavailability of the ester cephalosporins is increased when they are administered after food. Variable effects are observed when the ester agents are coadministered with antacids or H2-antagonists; while the absorption of cefetamet pivoxil was unaffected by coadministered antacids or H2-antagonists, the absorption of cefpodoxime proxetil was reduced.

Administration, Oral↗
PubMed1993

Determination of a new cephalosporin, SCE-2787, in serum and urine by high-performance liquid chromatography.

A high-performance liquid chromatographic method for the determination of a new-broad spectrum cephalosporin (I, SCE-2787) has been developed. The analyte was extracted from serum by precipitation of serum proteins with acetonitrile. Acetonitrile was extracted from the protein-free supernatant by dichloromethane. Urine was simply diluted with mobile phase. Separation was performed by ion-pair chromatography on a reversed-phase column (Nucleosil 5C18; 125 mm x 4.0 mm I.D.; 5 microns average particle size). The guard column was Perisorb RP18 (30 mm x 4.0 mm I.D.; 30-40 microns particle size). The mobile phase was acetonitrile-buffer solution containing 15 mM heptanesulphonic acid (pH 3.2) (4.5:95.5, v/v). Detection was performed at 235 nm with a diode-array detector, which also served to record ultraviolet spectra. The assay was sensitive, precise, accurate and fast. Specificity was controlled by on-line recording the ultraviolet spectrum of I and also by enzymic degradation with beta-lactamase. No interferences were observed during the analysis of serum and urine of healthy volunteers in pharmacokinetic studies.

Biological Assay↗
PubMed1993

[A Q fever epidemic in Berlin. The epidemiological and clinical aspects].

An epidemic of Q fever in Berlin affected at least 80 patients (45 females, 35 males; age range 1-75 years). Sheep were identified as the focus of infection: they had been brought to a veterinary clinic because of nonspecific symptoms. The peak incidence of the infection was in April and May, 1992. Most of the patients were staff or students at the veterinary clinic. This is the most northern and, at the same time largest, Q fever epidemic recorded in Germany over the last 28 years. The complement fixation reaction (CFR) was not helpful diagnostically in the acute stage of the disease as it remained negative in the first 14 days (CFR < or = 1:5). Most of the patients had sudden fever to over 40 degrees C, severe headache and dry cough. Pulmonary infiltrates were seen in the chest radiograph of 8 of the 10 patients presented in this contribution. Auscultation was largely negative. Two patients had signs of hepatic involvement (GPT as high as 71 U/l). The drug of choice was doxycycline at a dosage of 200 mg twice daily for 14 days.

Adolescent↗
PubMed1993

Pharmacokinetics of new oral cephalosporins, including a new carbacephem.

This review analyzes the pharmacokinetics of new oral cephalosporins, including esters, non-esters, and the carbacephem loracarbef, in healthy volunteers, as described in the literature and evaluated in several studies of our own. Single-dose studies have demonstrated considerable pharmacokinetic differences among these compounds. Cefixime, cefpodoxime proxetil, and cefetamet pivoxil are characterized by a low peak concentration and a prolonged half-life, while the other new agents have higher peak levels and shorter half-lives. Except for cefixime, the new oral cephalosporins are eliminated mainly by the kidneys. Pharmacokinetic studies in the elderly and in children indicate that the bioavailability of these agents is not influenced by age. Food increases the bioavailability of the ester cephalosporins but does not affect the absorption kinetics of the other new drugs.

Administration, Oral↗
PubMed1993

Diagnostic problems in lower respiratory tract infections.

The main problems of diagnosis in lower respiratory tract infection are the differentiation of infection from colonization or contamination, and the isolation of a reliable and true pathogen. The clinical findings and differentiation of patients into those with pneumonia or infective exacerbations of chronic bronchitis should provide a definitive early diagnosis. Expectorated sputum may be unreliable in pneumonia, because of contamination by oropharyngeal flora. Although blood cultures may be negative, they provide a precise diagnosis and should be obtained in all pneumonias admitted to hospital. Other more invasive procedures are transtracheal needle aspiration, fibrebronchoscopic techniques including protected specimen brush and bronchoalveolar lavage with quantitative culturing and cytological analysis, transthoracic needle aspiration, thoracoscopy--guided biopsy and open lung biopsy. Any invasive procedure in a severely ill patient should be carefully directed weighing the risks as well as the benefits, whilst taking the underlying disease and expected survival into consideration.

Bacteria↗
PubMed1993

Comparative pharmacokinetics and serum bactericidal activities of SCE-2787 and ceftazidime.

Ceftazidime and the new SCE-2787 are parenteral cephalosporins with a broad antimicrobial spectrum. Pharmacokinetics, serum bactericidal activities, and side effects were investigated in a randomized crossover study. A total of 12 healthy volunteers received a 20-min infusion of 1.5 g of SCE-2787 or 2.0 g of ceftazidime. Serum and urine concentrations were determined by the bioassay method and by high-pressure liquid chromatography (HPLC). The mean (+/- standard deviation) drug concentrations in serum at the end of infusion of SCE-2787 and ceftazidime were 124.4 +/- 23.8 and 233.1 +/- 54.1 mg/liter, respectively. The urine recovery of SCE-2787 was 87.8% +/- 5.5% of dose in 24 h and for ceftazidime was 85.8% +/- 6.3% of dose in 24 h. Metabolites of SCE-2787 could not be detected by HPLC in serum or urine. Pharmacokinetic parameters were calculated both with a noncompartmental analysis and on the basis of an open two-compartment model (drugs are administered into and eliminated from a central compartment only. However, reversible drug distribution from the central space occurs simultaneously into one peripheral space). The area under the concentration time curve from 0 h to infinity of SCE-2787 was 197.9 +/- 25.4 mg.h/liter, and that of ceftazidime was 334.2 +/- 40.0 mg.h/liter. SCE-2787 had a mean terminal half-life in the elimination phase of 109.0 +/- 15.3 min, while that of ceftazidime was 99.0 +/- 13.4 min. The volume of distribution at steady state of SCE-2787 was 17.1 +/- 1.6 liters/70 kg, and that of ceftazidime was 122.9 +/- 1.3 liters/70 kg. The mean residence time of SCE-2787 was 136.4 +/- 15.4 min, and that of ceftazidime was 122.9 +/- 12.7 min. The renal clearance per. 1.73 m2 of SCE-2787 was 103.1 +/- 12.3 ml/min, and that of ceftazidime was 80.6 +/- 13.2 ml/min. The serum bactericidal activities were measured with the microdilution method of Stratton and Reller (L. B. Reller and C. W. Stratton, J. Infect. Dis. 136:196-204, 1977) against 40 clinically isolated strains. One hour after administration, we measured mean reciprocal bactericidal titers of SCE-2787 and ceftazidime, respectively, against Escherichia coli of 388 and 243, against Klebsiella pneumoniae of 395 and 138, against Pseudomonas aeruginosa of 13.0 and 12.7, and against Staphylococcus aureus of 32.2 and 4.0. No severe side effects were observed in this single drug administration.

Adult↗
PubMed1993

Increased number of alveolar macrophages expressing surface molecules of the CD11/CD18 family in sarcoidosis and idiopathic pulmonary fibrosis is related to the production of superoxide anions by these cells.

This study was designed to investigate the expression and functional properties of leukocyte adhesion molecules (LeuCAM; CD11/CD18 family) on human alveolar macrophages (AM) from patients with sarcoidosis and idiopathic pulmonary fibrosis. Cells were obtained by bronchoalveolar lavage (BAL) from 17 patients with sarcoidosis (SA), 15 with idiopathic pulmonary fibrosis (IPF), and 14 nonsmokers (NS). Expression of LeuCAM on freshly isolated cells was studied using the peroxidase-antiperoxidase method with monoclonal antibodies (MoAb) detecting CD11a, CD11b, CD11c, and CD18. The functional properties of the adhesion molecules were studied by measuring superoxide anion production (O2-) of SA and IPF AM after blocking the CD18 molecule by an MoAb. Compared with nonsmokers, the samples from SA and IPF patients contained an increased number of AM expressing CD11a, CD11b, CD11c, and CD18 (all p < 0.008), which was correlated to the number of AM/ml BAL (p < 0.008). Spontaneous O2- secretion of AM was higher in SA (6.4 +/- 1.2 nMO2-/10(6) AM/120 min) and IPF (12.0 +/- 1.1 nMO2-/10(6) AM/120 min) compared with NS (2.5 +/- 0.2 nMO2-/10(6) AM/120 min) (both p < 0.008). Incubation of the AM with the MoAb anti-CD18 reduced the spontaneous O2- release from SA AM by 52 +/- 8% and from IPF AM by 49 +/- 3% but did not influence O2- release from NS AM (92 +/- 4%). Our data indicate that the increased expression of LeuCAM on AM in subjects with SA and IPF seems to be involved in the increased O2- production of these cells in both diseases.

Adult↗
PubMed1993

Fluoroquinolones: interaction profile during enteral absorption.

Fluoroquinolones are used worldwide in the treatment of severe infections. These drugs, however, can interact with other agents. This paper is a review of drug interactions with different quinolone derivatives at the absorption phase; the review deals mainly with the prototype quinolones, ciprofloxacin and ofloxacin, and also with some of the newer agents. The concomitant agents considered are food, H2-receptor antagonists, anticholinergic drugs and metallic cation-containing compounds. Food (standard breakfast), H2-receptor antagonists and anticholinergic drugs had no major effect on the bioavailability of the quinolones. However, antacids, ferrous sulfate and other metallic cation-containing compounds impaired the bioavailability of the quinolones. This effect is due to chelation between the functional groups of the quinolone molecule and the metallic cations, resulting in insoluble complexes that can be absorbed. The degree of impairment varied between different quinolone derivatives.

Administration, Oral↗