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T Abel

Publications and source records attributed to T Abel.

80 records · Page 5Linked to original sources

[Candida tropicalis as causative agent of septicemia (author's transl)].

In connection with microbiological findings in two patients, a report on septicemia caused by C. tropicalis is given. C. tropicalis is second in frequency to C. albicans in man. Because for the different biological properties of Candida species in each case of isolation of such fungi from clinical specimens an identification of the species is obligatory, because the generalizing diagnosis of "Candida mycosis" may be insufficient for the detection of epidemiological and pathogenetic associations. The possible primary resistance of C. tropicalis against the antimycotic 5-Fluorocytosine (Ancotil) is discussed. It is shown that the antigen similarity within the most important Candida species as e.g. between C. albicans and C. tropicalis may cause a false interpretation of serological results concerning the causative agent of the infection. For a safe inactivation of C. tropicalis on human skin, cleaning with 70% isopropyl alcohol for ten seconds is proposed. Because C. tropicalis is entering the human body preferably through food it is discussed whether a microbiological control of food for patients predisposed for such infections should be performed.

Adult↗

[Aspergillus serum precipitins in patients of a lung clinic].

The incidence and distribution of aspergillosis among patients of a lung clinic in West Berlin were recorded. The immunodiffusion test (IDT) was used on sera of 228 patients seen during one day to test for precipitins against A. fumigatus, A. flavus, and A. niger. Precipitating antibodies specific against A. fumigatus were found in five patients, in two of them A. fumigatus was isolated simultaneously from sputum. In order to obtain a clear view of the clinical occurrence of asperigillosis and its course one requires not only serological tests but also the isolation of Aspergillus in culture from sputum or bronchial secretion. IDT is useful for detecting aspergillosis and for screening persons harbouring Aspergillus in their respiratory tract.

Aspergillosis↗

Disseminated gonorrhea: diagnosis through contact tracing.

Over a 1-year period four patients were seen at the Jewish General Hospital with presumed disseminated gonococcemia. The patients' histories, clinical findings and responses to therapy strongly supported this diagnosis; however, cultures from various sites were negative for Neisseria gonorrhoeae in all four patients. Sexual contacts of these patients were traced and appropriate cultures were found to be positive, demonstrating the importance of tracing sexual contacts to help confirm the diagnosis in such patients.

Adult↗

Environmental enrichment modifies the PKA-dependence of hippocampal LTP and improves hippocampus-dependent memory.

cAMP-dependent protein kinase (PKA) is critical for the expression of some forms of long-term potentiation (LTP) in area CA1 of the mouse hippocampus and for hippocampus-dependent memory. Exposure to spatially enriched environments can modify LTP and improve behavioral memory in rodents, but the molecular bases for the enhanced memory performance seen in enriched animals are undefined. We tested the hypothesis that exposure to a spatially enriched environment may alter the PKA dependence of hippocampal LTP. Hippocampal slices from enriched mice showed enhanced LTP following a single burst of 100-Hz stimulation in the Schaffer collateral pathway of area CA1. In slices from nonenriched mice, this single-burst form of LTP was less robust and was unaffected by Rp-cAMPS, an inhibitor of PKA. In contrast, the enhanced LTP in enriched mice was attenuated by Rp-cAMPS. Enriched slices expressed greater forskolin-induced, cAMP-dependent synaptic facilitation than did slices from nonenriched mice. Enriched mice showed improved memory for contextual fear conditioning, whereas memory for cued fear conditioning was unaffected following enrichment. Our data indicate that exposure of mice to spatial enrichment alters the PKA dependence of LTP and enhances one type of hippocampus-dependent memory. Environmental enrichment can transform the pharmacological profile of hippocampal LTP, possibly by altering the threshold for activity-dependent recruitment of the cAMP-PKA signaling pathway following electrical and chemical stimulation. We suggest that experience-dependent plasticity of the PKA dependence of hippocampal LTP may be important for regulating the efficacy of hippocampus-based memory.

Action Potentials↗

Strain-dependent differences in LTP and hippocampus-dependent memory in inbred mice.

Many studies have used "reverse" genetics to produce "knock-out" and transgenic mice to explore the roles of various molecules in long-term potentiation (LTP) and spatial memory. The existence of a variety of inbred strains of mice provides an additional way of exploring the genetic bases of learning and memory. We examined behavioral memory and LTP expression in area CA1 of hippocampal slices prepared from four different inbred strains of mice: C57BL/6J, CBA/J, DBA/2J, and 129/SvEms-+(Ter?)/J. We found that LTP induced by four 100-Hz trains of stimulation was robust and long-lasting in C57BL/6J and DBA/2J mice but decayed in CBA/J and 129/SvEms-+(Ter?)/J mice. LTP induced by one 100-Hz train was significantly smaller after 1 hr in the 129/SvEms-+(Ter?)/J mice than in the other three strains. Theta-burst LTP was shorter lasting in CBA/J, DBA/2J, and 129/SvEms-+(Ter?)/J mice than in C57BL/6J mice. We also observed specific memory deficits, among particular mouse strains, in spatial and nonspatial tests of hippocampus-dependent memory. CBA/J mice showed defective learning in the Morris water maze, and both DBA/2J and CBA/J strains displayed deficient long-term memory in contextual and cued fear conditioning tests. Our findings provide strong support for a genetic basis for some forms of synaptic plasticity that are linked to behavioral long-term memory and suggest that genetic background can influence the electrophysiological and behavioral phenotypes observed in genetically modified mice generated for elucidating the molecular bases of learning, memory, and LTP.

Animals↗

Different training procedures recruit either one or two critical periods for contextual memory consolidation, each of which requires protein synthesis and PKA.

We have used a combined genetic and pharmacological approach to define the time course of the requirement for protein kinase A (PKA) and protein synthesis in long-term memory for contextual fear conditioning in mice. The time course of amnesia in transgenic mice that express R(AB) and have genetically reduced PKA activity in the hippocampus parallels that observed both in mice treated with inhibitors of PKA and mice treated with inhibitors of protein synthesis. This PKA- and protein synthesis-dependent memory develops between 1 hr and 3 hr after training. By injecting the protein synthesis inhibitor anisomycin or the PKA inhibitor Rp-cAMPs at various times after training, we find that depending on the nature of training, contextual memory has either one or two brief consolidation periods requiring synthesis of new proteins, and each of these also requires PKA. Weak training shows two time periods of sensitivity to inhibitors of protein synthesis and PKA, whereas stronger training exhibits only one. These studies underscore the parallel dependence of long-term contextual memory on protein synthesis and PKA and suggest that different training protocols may recruit a common signaling pathway in distinct ways.

Acoustic Stimulation↗

Neuropsychiatric lupus.

Sixty-six systemic lupus erythematosus (SLE) patients followed prospectively had 77 episodes of neuropsychiatric lupus (NPL). Patients with NPL had more SLE manifestations than patients without NPL. Serologic data and cerebrospinal fluid analysis were not helpful in identifying an episode of NPL. Electroencephalogram was abnormal in more than 1/2 and brain scans in more than 3/4 of patients. In 74 episodes with a known outcome, 54 improved, 44 having been treated with increased corticosteroids. Patients with NPL had a higher incidence of deaths compared to patients without NPL.

Adolescent↗