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Biomedical subjects

A Heim

Publications and source records attributed to A Heim.

6 recordsLinked to original sources
PubMed2025

Habitat Specialisation Impacts Clownfish Demographic Resilience to Pleistocene Sea-Level Fluctuations.

Habitat fragmentation and loss are key threats to biodiversity, yet their impacts on marine species remain poorly understood. Clownfishes, which rely on sea anemones for shelter and reproduction, provide an interesting model to explore how ecological specialisation mediates species responses to habitat perturbations. We used whole-genome data from 382 individuals across 10 species with varying host specialisations to reconstruct demographic histories and infer spatial genetic structure to assess the impact of Pleistocene sea-level fluctuations. Generalist species, associated with multiple hosts, maintained stable effective population sizes () and population connectivity during habitat fragmentation, reflecting resilience to environmental instability. In contrast, specialists experienced severedeclines and genetic structuring, driven by their dependence on specific hosts, without signs of population recovery following habitat reconnection. Spatial genomic analyses identified the Indonesian Through-Flow as a key dispersal corridor and the Coral Triangle as a critical hub of genetic diversity, while continental shelves and extensive open ocean regions appeared as barriers to gene flow. Our findings reveal how host specialisation shapes clownfish population dynamics, emphasising the importance of incorporating ecological dependencies into conservation assessments and deepening our understanding of species responses to ecological constraints and environmental changes over evolutionary timescales.

Animals↗
PubMed1992

Significance of coronary angiography, left heart catheterization, and endomyocardial biopsy for the diagnosis of idiopathic dilated cardiomyopathy.

Many physicians assume that a reliable diagnosis of idiopathic dilated cardiomyopathy can be made by noninvasive methods, mainly echocardiography. On the other hand, use of endomyocardial biopsy in those patients who have undergone left heart catheterization and who demonstrate left ventricular dysfunction of unknown origin is increasing. Therefore the purpose of this study was to investigate the yield of that diagnostic strategy in patients with the tentative diagnosis of idiopathic dilated cardiomyopathy. Between 1980 and 1988, 3.2% of our 15,442 patients were diagnosed as having idiopathic dilated cardiomyopathy on the basis of left heart catheterizations and coronary angiograms. Idiopathic dilated cardiomyopathy was diagnosed in 444 patients on the basis of clinical data and results of noninvasive tests before catheterization, but in only 295 of these cases was the diagnosis confirmed by means of coronary angiography and left heart catheterization (predictive value of noninvasive tests is 66%). The remaining 34% of patients demonstrated extensive coronary artery disease (13%), significant valvular heart disease (11%), and other or no heart disease (10%). The diagnostic sensitivity of noninvasive tools (patient history, ECG, stress test, echocardiography) was only 59%. Left heart catheterization can easily be combined with endomyocardial biopsy. With the use of histologic techniques, specific heart muscle diseases were detectable in 3.5% of 209 patients, but in only 1% could therapeutic consequences be determined. Thus coronary angiography and left heart catheterization are mandatory for the correct diagnosis of idiopathic dilated cardiomyopathy.(ABSTRACT TRUNCATED AT 250 WORDS)

Biopsy↗
PubMed1992

Synergistic interaction of interferon-beta and interferon-gamma in coxsackievirus B3-infected carrier cultures of human myocardial fibroblasts.

The antiviral effects of human interferon-beta (IFN-beta) and human recombinant interferon-gamma (rIFN-gamma) were studied in persistently coxsackievirus B3-infected carrier cultures of human myocardial fibroblasts over a period of 21 days. Synergism was observed with concentrations as low as 30 IU of IFN-beta plus 10 IU of rIFN-gamma/mL, reducing mean viral titers from 6.0 x 10(7) to 1.3 x 10(4) pfu/mL and number of infected cells from 14.4% to 0.1% as determined by quantitative in situ hybridization. Higher concentrations of IFNs (both > or = 30 IU/mL) were associated with transient antagonism followed by antiviral synergism. With 100 IU of IFN-beta plus 30 IU of rIFN-gamma/mL, elimination of infectious virus was consistently achieved and sustained for 6 weeks after cessation of IFN application, whereas at least threefold higher concentrations were required with single drugs. In summary, our data support a concept of low-dose IFN combination schedules that might become useful in the treatment of enteroviral heart disease.

Cells, Cultured↗
PubMed1991

Radioimmunoimaging of subacute infective endocarditis using a technetium-99m monoclonal granulocyte-specific antibody.

Immunoscintigraphy with a technetium-99m murine monoclonal IgG1 antibody directed against non-specific cross-reacting antigen (NCA-95) and carcinoembryonic antigen was performed with 20 patients with suspected subacute infective endocarditis (SIE) and 6 controls with suspected inflammatory/infectious disease elsewhere in the body. Immunoscintigraphy and echocardiography localised SIE in 11 of 15 patients in whom the disease could be confirmed. In 4 patients with validated SIE, the immunoscan was abnormal, and the echocardiogram was normal. In another 4 patients, the result was exactly the opposite. These findings suggest that the combination of immunoscintigraphy and echocardiography improves diagnostic efficacy in patients with suspected SIE.

Adolescent↗
PubMedDate not supplied

[Relevant pharmacologic data as a guide for use of beta-blockers in psychiatry].

In addition to their competitive blockade of the beta-receptors, beta-adrenergic-blocking drugs possess ancillary properties that may modulate their clinical effects. Among these properties, beta 1-selectivity, intrinsic sympathomimetic activity, lipid solubility, may affect pharmacokinetic and pharmacodynamic properties of beta-blockers. It could appear that lipid soluble drugs gain access to the Central Nervous System (CNS) more easily. But CNS effects of beta-blockers are probably modulated by other parameters. With those pharmacological data, the authors propose briefly a schematic use of main beta-blockers in psychiatry.

Adrenergic beta-Antagonists↗