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H Lode

Publications and source records attributed to H Lode.

At least 109 records · Page 6Linked to original sources
PubMed1992

Superoxide anion release induced by platelet-activating factor is increased in human alveolar macrophages from smokers.

This study was designed to investigate the effects of the platelet-activating factor (PAF) on the superoxide anion production (O2.) of human alveolar macrophages (AM) from nonsmoking (n = 18) and smoking (n = 30) subjects. Freshly isolated cells were stimulated with (PAF) or with a phorbol ester (phorbol 12-myristate 13 acetate (PMA)). Stimulation with PAF led to a dose-dependent increase of O2. production by AM in both groups. The median effective dose (EC50) for PAF action on O2. production of smoker AM was 0.5 x 10(-8) M, compared to nonsmoker AM with an EC50 of 1.0 x 10(-7) M. This effect of PAF was blockable by the PAF-antagonist WEB 2086 in a dose-dependent manner. Comparison of the relative increase of O2. production after PAF-stimulation showed that smoker cells were significantly more sensitive to PAF than nonsmoker cells (p less than 0.01). In contrast to the findings with PAF, the relative increase of O2. production after PMA-stimulation showed no differences between smoker and nonsmoker AM. Our data suggest that AM from smoking subjects are more sensitive to PAF than AM from nonsmokers.

Bronchoalveolar Lavage Fluid↗
PubMed1992

Azithromycin in lower respiratory tract infections.

Azithromycin is a new azalide antimicrobial agent which has a broad spectrum of activity against common lower respiratory tract pathogens including pneumococci, staphylococci, Legionella species, Mycoplasma and Chlamydia species. In particular, it is more active against Haemophilus influenzae than other macrolides. In comparison to other new macrolides, azithromycin achieves higher tissue and intracellular concentrations and these concentrations are sustained for several days after dosing due to a long elimination half-life. The efficacy of azithromycin against lower respiratory tract infections has been proven in several clinical studies. Once-daily dosing with azithromycin, over a 3- or 5- day period was as effective as a 10-day course of other commonly used antibiotics such as amoxycillin/clavulanic acid, erythromycin or cefaclor in lower respiratory tract infections. Azithromycin short-course therapy may offer an advantage in terms of patient compliance and the duration of treatment.

Animals↗
PubMed1992

[Ambulant atypical pneumonia: clinical diagnosis and therapy].

Atypical pneumonias are caused by mycoplasma, chlamydia and legionella species. From a clinical point of view the disease is comparable to influenza-like infections. Macrolide antibiotics covered the species which are most important. Especially new macrolides displayed better pharmacokinetic properties, allowing dose reduction and reduced frequency of intake. For legionella infections also therapy with modern quinolones is possible.

Chlamydia Infections↗
PubMed1991

Fibrin degradation product D-dimer in the diagnosis of pulmonary embolism.

The study objective was to determine the specificity and sensitivity of plasma concentrations of D-dimer, a fibrin degradation product, as a marker for ongoing thrombotic and thrombolytic events in pulmonary embolism. A prospective study was performed in 74 patients with suspected pulmonary embolism who appeared in the emergency room with dyspnea and/or chest pain. The presence of pulmonary embolism was established by positive findings either in pulmonary angiography or lung scan. D-dimer concentrations were determined in all patients. In 11 patients with positive pulmonary angiography, D-dimer concentrations were monitored for 6-12 days. D-dimer concentrations were determined by a quantitative enzyme-linked immunoassay. Plasma probes of 26 patients (16 with/10 without positive pulmonary angiography) were re-assayed with a semiquantitative latex agglutination assay. D-dimer levels were significantly higher in patients with pulmonary embolism (greater than 1000 ng/mL in 41 out of 43) than in those without (less than 1000 ng/mL in all 21 patients) (p less than 0.01). The sensitivity and specificity for the ELISA were found to be 95% and 100%, respectively, for establishing the diagnosis of pulmonary embolism. In the latex assay the values were 81% and 60%, respectively. It is concluded that in patients with dyspnea and/or chest pain, determination of D-dimer in plasma by ELISA adds a valuable tool to the noninvasive diagnostic procedure for pulmonary embolism. From the time-course of D-dimer values we conclude that this assay might be valuable up to at least 6 days after symptom onset. The assay, however, is unreliable in malignancies or after surgery.

Adult↗
PubMed1991

Evidence for a platelet-activating factor receptor on human alveolar macrophages.

In this report we demonstrate evidence which strongly suggests that human alveolar macrophages possess receptor for the platelet activating factor (PAF). We investigated the effects of PAF by measuring (a) the intracellular free calcium concentration [Ca2+]i, using the fura-2 method in single isolated cells and (b) the production of superoxide anion. PAF increased [Ca2+]i in a dose-dependent manner (EC50 = 1 x 10(-8) M), whereas lyso-PAF had no effect. The initial increase of [Ca2+]i was followed by a slow decrease to a sustained elevation of [Ca2+]i significantly above basal values. While the initial rise in [Ca2+]i was only slightly reduced in Ca(2+)-free medium (1 mM EGTA), the sustained phase was totally abolished. The sustained calcium increase was also blocked after preincubation of AM with the calcium-channel blocker nitrendipine. PAF increased the production of superoxide anion (O2-) by human alveolar macrophages in a dose- dependent manner. The effects of PAF on [Ca2+]i and (O2-) could be blocked by the PAF-specific antagonist WEB 2086 dose dependently, indicating a receptor-mediated event.

Adult↗
PubMed1991

[Use and risk of antibacterial chemotherapy from the medical point of view].

The evaluation of the efficacy and possible intolerance of an antibacterial chemotherapy is based on the exact analysis of patient specific signs and symptoms, pathogenetic factors of the specific bacteria and parameters of the specific substance. One has to differentiate between usefulness of the antibiotics (effect) and the possible risks for the patient as well as for the physician involved. Today the legal regulations have become so strict for treatment with new substances in phase II to III studies that in most of the new chemotherapeutic substances the relationship between efficacy and possible intolerance reactions may be judged as optimal for both the patient and the physician. Our own experiences have shown that patients involved in studies with well designed protocols are better controlled and in most instances also better treated than patients treated outside such protocols.

Anti-Bacterial Agents↗
PubMed1991

The pharmacokinetics of azithromycin and their clinical significance.

The usefulness of erythromycin is limited by its poor pharmacokinetic profile which is characterised by low blood levels and poor gastric acid stability. Erythromycin's short half-life means that a four-times daily dosage schedule is required for effective treatment. In comparison, the azalide structure of azithromycin confers a much improved pharmacokinetic profile. The bioavailability of azithromycin is approximately 37% in humans (25% for erythromycin). Serum concentrations decline in a polyphasic manner and the relatively short serum half-life (11-14 hours recorded 8-24 hours after last dose) is an indication of the initial rapid distribution of drug into the tissues. The low serum levels recorded 24 hours or more after the end of administration are thought to reflect the slow release of azithromycin from tissues. Tissue concentrations exceed serum concentrations by as much as 100-fold following a single 500 mg oral dose. Macrophages and polymorphonuclear leucocytes concentrate azithromycin at levels greater than those found in tissues themselves. During multiple dosing, tissue half-life increases with duration of administration and the tissue to serum ratio further increases. High concentrations of drug are found in tissues such as tonsil, lung, prostate, liver and lymph nodes with relatively low concentrations in fat and muscle. Significantly, the sustained high levels of drug in the tissues appears to correlate with good in vivo activity. Two 1.5 g regimens have been investigated in clinical trials: 500 mg on day 1, followed by 250 mg daily on days 2 to 5; or 500 mg daily for three days.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗
PubMed1991

The use of oral temafloxacin compared with a parenteral cephalosporin in hospitalized patients with pneumonia.

In a European open, multicentre, prospective clinical trial, 100 hospitalized adult patients (61 males; 18-91 years old (mean age 62] with bacterial pneumonia, diagnosed clinically and radiographically, were randomized to receive either oral temafloxacin 600 mg twice daily (n = 49) or intravenous cefotaxime 2 g thrice daily (n = 51). Signs, symptoms and chest radiographs were assessed during, at the end of therapy and at follow-up eight to ten days after the last dose. Patients were treated for a maximum of ten days. Sputum was obtained for culture before, during and after therapy. The clinical cure rate for the temafloxacin treatment group was 90%, the bacteriological cure rate was 91% and the radiological response rate was 95%. The respective rates for the cefotaxime-treated group were 92%, 96% and 100%. There were no significant differences between the treatment groups for clinical or microbiological outcome, premature study discontinuation, or adverse events. Oral temafloxacin was clinically and bacteriologically equivalent to intravenous cefotaxime in the treatment of hospitalized adults with bacterial pneumonia.

Administration, Oral↗
PubMed1991

Endothelin increases [Ca2+]i, protein phosphorylation, and O2-. production in human alveolar macrophages.

The goal of the present study was to investigate whether endothelin (ET) increases O2-.production in alveolar macrophages and to establish which second messengers are activated by ET. We measured the effects of ET on cytosolic free calcium concentration [Ca2+]i, protein phosphorylation, and O2-.production in human alveolarmacrophages (HAM). Human macrophages were obtained by bronchoalveolar lavage. [Ca2+]i was measured by the fura-2 method both in cell suspensions and in isolated single macrophages. Protein phosphorylation was assessed by gel electrophoresis and autoradiography after labeling the cells with 32P. ET increased [Ca2+]i in a dose-dependent manner (50% effective concentration = 1 x 10(-7)M). At a concentration of 10(-6)M ET, [Ca2+]i rose from basal values of 121 +/- 23 to 456 +/- 41 nM. This increase was comparable with the increase of [Ca2+]i induced by N-formyl-L-methionyl-L-leucyl-L-phenylalanine and platelet-activating factor (PAF; 1-O-alkyl-2-acetyl-sn-glyceryl-3-phosphorylcholine). The initial rise in [Ca2+]i and the sustained phase were significantly reduced in calcium-free medium (1 mM ethyleneglycol-bis(beta-aminoethyl ether)-N,N,N',N'-tetraacetic acid) and after preincubation of HAM with the calcium channel blocker nitrendipine (10(-7)M). Exposure of 32P-labeled HAM to ET for 1 min induced the phosphorylation of a group of 48-kDa proteins and of a 35-kDa protein. The ET-induced 32P incorporation into the 48-kDa proteins was less pronounced than the 12-O-tetra-decanoylphorbol-13-acetate or PAF-induced response (168 +/- 24 vs. 356 +/- 68 and 278 +/- 61% of control).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Pulmonary schistosomiasis resembling acute pulmonary tuberculosis.

Pulmonary involvement of schistosomiasis is usually characterized by a miliary mottling or diffuse nodular infiltrates. In most cases, pulmonary involvement is associated with an apparent clinical involvement of other organs. This report describes a 35 yr old patient who developed a cavity, a parenchymatous infiltrate and hilar adenopathy in association with pulmonary schistosomiasis. Schistosoma eggs were demonstrated in transbronchial biopsies from the lung. Pulmonary involvement of schistosomiasis is reviewed and atypical features are discussed, which may lead to diagnostic difficulties, particularly compared to tuberculosis.

Adult↗
PubMed1991

[Clinical aspects of endocarditis].

Considering the incidence of infectious endocarditis this disease is still an important clinical entity in internal medicine departments. Leading symptoms are fever, cardiac murmurs, embolic phenomena, skin alterations and also sometimes CNS-disturbances. Two different clinical endocarditis entities can be separated: an acute aggressive course of endocarditis and the subacute course (endocarditis lenta). Diagnostic procedures are mainly based on positive blood cultures and echocardiographic detection of cardiac vegetations. In case of a progressive development of cardiac insufficiency, non treatable infection, large vegetations on valve and embolic phenomena a prosthetic valve implantation is indicated.

Endocarditis, Bacterial↗
PubMed1991

[Pharmacokinetic aspects of tuberculosis therapy with a fixed combination of rifampicin, isoniazide and pyrazinamide].

The here described investigations show correspondingly that the administration of isoniazid, rifampicin and pyrazinamide in a fixed combination of the administration of the individual substances is bioequivalent under pharmacokinetic aspects. Further investigations on large populations of patients must, however, still confirm whether or not the advantages of the fix combination striven for or theoretically to be expected can be proved in practice.

Biological Availability↗