PubMed Health⌕ Search

Biomedical subjects

M Diemer

Publications and source records attributed to M Diemer.

9 recordsLinked to original sources

Interaction between aspirin and ACE inhibitors in patients with heart failure.

Both aspirin (acetylsalicylic acid) and ACE inhibitors are often used concomitantly, especially in patients with both heart failure and ischaemic heart disease, which is the most common underlying cause of heart failure. The safety of the association has been questioned because both drugs affect a related prostaglandin-mediated pathway. Thanks to their vasodilating properties, prostaglandins play an important role in heart failure where peripheral vasoconstriction occurs. Some of the beneficial effects of ACE inhibitors might be related to reduced degradation of bradykinin that enhances the synthesis of prostaglandins, while aspirin, through inhibiting the enzyme cyclo-oxygenase, inhibits the production of prostaglandins. To date no prospective study has been conducted to investigate the effect of long term aspirin treatment in the postinfarction period allowing the possible impact of the interaction between aspirin and ACE inhibitors upon survival to be confirmed or negated. However, the practitioner needs to know how to optimise the treatment of his or her patients. In order to stimulate arguments for and against the use of aspirin in patients with heart failure receiving ACE inhibitors, we searched MEDLINE from 1960 to 2000 using the key words heart failure, aspirin, and ACE inhibitors for English language articles and conducted a review of the available data. We report on the potential mechanisms of the interaction and the results of experimental studies on haemodynamic parameters. Results of retrospective clinical studies, subgroup analysis that were undertaken to evaluate the overall action upon haemodynamic parameters and survival of the association are summarised. Conflicting conclusions have been reported in the literature. Many explanations can be advanced to try to understand these conflicting conclusions: differences in study design (results of retrospective trials have to be interpreted with caution); differences in the choice of the evaluation parameter (problem of the clinical relevance of haemodynamic parameters); differences in the characteristics of the patient (different underlying cardiopathy, e.g. heart failure, hypertension or ischaemic cardiopathy); and differences in the type and the dosage of each treatment (especially ACE inhibitors and aspirin since an interaction might occur more often with dosage of aspirin greater than 250mg).

Angiotensin-Converting Enzyme Inhibitors↗

[Survey of the negativation of bacteriologic tests in patients with active pulmonary tuberculosis: how long should the isolation be?].

The risk of contamination by contact with patients with tuberculosis is reduced by isolation of patients until negativation of direct sputum analysis for the research of tuberculosis bacilli. To evaluate the efficacy of this isolation, we compared, in 32 patients with active tuberculosis, the results of direct examination and culture of the sputum and the clinical outcome. Thirty-two successive patients hospitalized in the same internal medicine unit, received antituberculosis drugs and had 3 sputum examinations per week with direct analysis and culture until negativation of the 3 direct examinations. Then, isolation ended. At the time of direct-negativation, 14 of the 32 patients kept positive cultures. In the 18 remaining subjects, the cultures became negative, about seven days before direct-negativation. Patients with negative cultures had more frequently weight increase (83% versus 71%), were more rapidly without fever (11 days versus 19 days), had less cough and had less severe radiologic disease (50% versus 75%) compared to patients with positive cultures but these differences were not statistically significant due to the small sample size. In tuberculosis patients, 3 successive negative direct sputum examinations do not eliminate the risk of tuberculosis transmission, specially to hospitalized or immunocompromised patients. The risk of contamination in these cases, although unknown, may be weak. Terminating isolation should not be based on sputum examination alone, but also on other factors such as the clinical course (resolution of cough and fever, weight), the initial number of bacilli, and the severity of the radiological lesions.

Adult↗

Plant diversity and productivity experiments in european grasslands

At eight European field sites, the impact of loss of plant diversity on primary productivity was simulated by synthesizing grassland communities with different numbers of plant species. Results differed in detail at each location, but there was an overall log-linear reduction of average aboveground biomass with loss of species. For a given number of species, communities with fewer functional groups were less productive. These diversity effects occurred along with differences associated with species composition and geographic location. Niche complementarity and positive species interactions appear to play a role in generating diversity-productivity relationships within sites in addition to sampling from the species pool.

Journal Article↗

Impediments to writing do-not-resuscitate orders.

BACKGROUND: Physicians are frequently unaware of their patients' desires regarding end-of-life care. Consequently, opportunities to implement do-not-resuscitate (DNR) orders are often missed. OBJECTIVE: To determine the reasons attending physicians do not write DNR orders when patients face increased mortality. METHODS: Over 4 months, the medical records of all inpatients on the General Medicine Service were reviewed at the time of discharge to identify patients with conditions predicting increased mortality. These cases were presented to a 5-member panel who decided if a DNR order was indicated. Reasons for missing DNR orders were discussed with the attending physicians. RESULTS: Of 613 consecutive admissions, the panel identified 149 patients (24%) for whom DNR orders were indicated. In 88 (59%) of these, DNR orders were absent. The lack of a DNR order did not correlate with age (P = .95), sex (P = .61), or race (P = .80). The attending physicians' explanations for not writing DNR orders in these 88 cases included the belief that the patient was not in imminent danger of death (n = 49 [56%]), the belief that the primary physician should discuss DNR issues (n = 43 [49%]), and the lack of an appropriate opportunity to discuss end-of-life issues (n = 38 [43%]). In 11 (12%) of the 88 cases, patients or their families did not accept the recommendation for a DNR order. No physicians expressed concerns regarding the morality of DNR orders, discomfort discussing end-of-life issues, or the threat of litigation as reasons for not writing a DNR order. CONCLUSIONS: Limitations in the extent and depth of the physician-patient relationship appear to be the most frequent impediments to writing DNR orders in our institution.

Adult↗

Intraspecific brood parasitism: a strategy for floating females in the European starling.

In many bird species, there is a floating population of females that are excluded from breeding because of competition for limited breeding resources. Female floaters may enhance their reproductive success by engaging in intraspecific brood parasitism. We studied female floaters in a population of European starlings, Sturnus vulgaris, in order to determine their identity and potential parasitic behaviour. Females were caught after being attracted to nestboxes with artificial nests during 1993-1995. None of the females was known to have a nest of her own at capture but 47% of the females either laid an egg in the nest or carried a fully developed egg within the reproductive tract, indicating that they were intraspecific brood parasites. The floating females were significantly younger and smaller than breeding females. Of 13 females equipped with radiotransmitters and followed daily, all but one started a breeding attempt of their own after 3-8 days and the majority settled as secondary females or mated with males where the original female had disappeared. This suggests that females that are unable to compete successfully for nest sites or males early in the breeding season may use intraspecific brood parasitism to enhance reproductive success during the period that they are constrained from breeding. The importance of settling rapidly because of a seasonal decline in reproductive success may also promote the evolution of intraspecific brood parasitism in the starling. The relative reproductive success of combining egg dumping with breeding compared with traditional breeding will depend on the costs of delaying breeding as well as the probability of finding a mate later in the breeding season. Copyright 1999 The Association for the Study of Animal Behaviour.

Journal Article↗

Thrombolytic and antithrombotic efficacy of the platelet GPIIb-IIIa antagonist DMP728.

OBJECTIVE: This study was undertaken to determine the antithrombotic and thrombolytic efficacy of DMP728 alone and in conjunction with thrombolytic agents. BACKGROUND: Coronary artery reocclusion continues to be a significant clinical problem after thrombolytic therapy or balloon angioplasty, with incidence rates of 5-20% regardless of thrombolytic intervention. To date, no adjunctive therapy has been shown to eliminate the incidence of rethrombosis after thrombolysis. DMP728, a novel small-molecular-weight platelet GPIIb-IIIa receptor antagonist, has been shown to prevent rethrombosis after thrombolysis in various arterial thrombosis models in dogs. It might therefore have potential utility in optimizing the clinical outcome of currently available thrombolytic agents. The present investigation was designed to examine the thrombolytic potential of DMP728 alone and in conjunction with different thrombolytic agents. METHODS: The deaggregatory effect of DMP728 in reversing human platelet aggregation after initiation of platelet aggregation by 10 mumol/l adenosine 5'-diphosphate was determined using light-transmittance aggregometry. The in-vitro efficacy of DMP728, alone and in combination with thrombolytic drugs, in dispersing a preformed platelet-rich clot was determined using a clot-dispersion assay. In addition, the in-vivo thrombolytic effects of DMP728, alone and in conjunction with streptokinase, were examined in an electrolytically induced femoral artery thrombosis model in dogs. RESULTS: DMP728 had concentration-dependent deaggregatory and thrombolytic effects in reversing aggregates and in dispersing a preformed platelet-rich thrombus in vitro. Furthermore, it exhibited significant potentiation (P < 0.01) when combined with different thrombolytic drugs such as streptokinase, tissue-type plasminogen activator (t-PA) and urokinase in lysing platelet-rich thrombus. DMP728 had significant in-vivo thrombolytic effects along with synergy in fully restoring arterial flow upon its concomitant use with subeffective to ineffective doses of streptokinase in an electrolytically induced femoral artery thrombosis model in dogs. It also reduced the time to reperfusion and prevented the incidence of rethrombosis after streptokinase. CONCLUSIONS: These findings suggest the potential utility and benefits of DMP728, not only in preventing arterial thrombosis but also in optimizing the efficacy of thrombolytic drugs.

Adenosine Diphosphate↗