Knowledge, attitudes, behaviors, and serological status related to Chagas disease among Latin American migrants in Germany: A cross-sectional study in six German cities.

Background: Little is known about knowledge, attitudes and behaviors concerning Chagas disease (CD) among Latin American migrants in Germany to inform public health decision making. Methods: A cross-sectional, questionnaire-based study was conducted between March 2014 and October 2019 among Latin American migrants in six cities in Germany to obtain information on migration history, socioeconomic and insurance status, knowledge about CD, potential risk factors for Trypanosoma cruzi infection, and willingness to donate blood or organs. Results: 168 participants completed the questionnaire. The four countries with the highest proportion of participants contributing to the study population were Colombia, Mexico, Peru and Ecuador. Before migrating to Europe, the majority of the study population resided in an urban setting in houses made of stone or concrete, had higher academic education and was integrated into the German healthcare and healthcare insurance system. The majority of all study participants were also willing to donate blood and organs and a quarter of them had donated blood previously. However, many participants lacked basic knowledge about symptoms and modes of transmission of Chagas disease. One out of 56 serologic tests (1.8%) performed was positive. The seropositive female participant born in Argentina had a negative PCR test and no signs of cardiac or other organ involvement. Conclusions: The study population does not reflect the population structure at risk for T. cruzi infection in endemic countries. Most participants had a low risk profile for infection with T. cruzi. Although the sample size was small and sampling was not representative of all persons at risk in Germany, the seroprevalence found was similar to studies previously conducted in Europe. As no systematic screening for T. cruzi in Latin American blood and organ donors as well as in women of child-bearing age of Latin American origin is implemented in Germany, a risk of occasional transmission of T. cruzi remains.

Evaluation of new colorimetric vitek 2 yeast identification card by use of different source media.

The new colorimetric Vitek 2 YST card was evaluated for identification of yeasts (136 strains) with respect to the influence of different source media. The Vitek 2 YST card achieved satisfactory results for all yeast species tested, with the exception of Candida guilliermondii, Candida norvegensis, Candida parapsilosis, Candida rugosa, and Candida tropicalis. After simple additional tests, 93.7% of all the strains tested were correctly identified. A significant influence of the isolation medium on the identification rate could not be observed.

Nuclear calcineurin is a sensor for detecting Ca2+ release from the nuclear envelope via IP3R.

In continuously beating cells like cardiac myocytes, there are rapid alterations of cytosolic Ca2+ levels. We therefore hypothesize that decoding Ca2+ signals for hypertrophic signaling requires intracellular Ca2+ microdomains that are partly independent from cytosolic Ca2+. Furthermore, there is a need for a Ca2+ sensor within these microdomains that translates Ca2+ signals into hypertrophic signaling. Recent evidence suggested that the nucleus of cardiac myocytes might be a Ca2+ microdomain and that calcineurin, once translocated into the nucleus, could act as a nuclear Ca2+ sensor. We demonstrate that nuclear calcineurin was able to act as a nuclear Ca2+ sensor detecting local Ca2+ release from the nuclear envelope via IP3R. Nuclear calcineurin mutants defective for Ca2+ binding failed to activate NFAT-dependent transcription. Under hypertrophic conditions Ca2+ transients in the nuclear microdomain were significantly higher than in the cytosol providing a basis for sustained calcineurin/NFAT-mediated signaling uncoupled from cytosolic Ca2+. Measurements of nuclear and cytosolic Ca2+ transients in IP3 sponge mice showed no increase of Ca2+ levels during diastole as we detected in wild-type mice. Nuclei, isolated from ventricular myocytes of mice after chronic Ang II treatment, showed an elevation of IP3R2 expression which was dependent on calcineurin/NFAT signaling and persisted for 3 weeks after removal of the Ang II stimulus. These data provide an explanation how Ca2+ and calcineurin might regulate transcription in cardiomyocytes in response to neurohumoral signals independently from their role in cardiac contraction control. KEY MESSAGES: • Calcineurin acts as an intranuclear Ca2+ sensor to promote NFAT activity. • Nuclear Ca2+ in cardiac myocytes increases via IP3R2 upon Ang II stimulation. • IP3R2 expression is directly dependent on calcineurin/NFAT.

Epidemiology of Chagas disease in Europe: many calculations, little knowledge.

Chagas disease and its causative agent Trypanosoma cruzi are endemic in almost all countries in South and Middle America. Currently, there are more than 10 million affected people. It is the most common reason for heart failure and a frequent cause of intestinal problems in Latin America. The phenotype of the Chagas cardiomyopathy is varying. Dilative cardiomyopathy, often accompanied by an apical aneurysm is the most common finding in the end stage heart failure, but rhythm disorders like conduction blocks, ventricular or supraventricular forms of tachycardia or repolarization changes occur as well, mainly in the early stages. Migration of infected people leads to a distribution from the endemic countries to North America and Europe. Although more than 500,000 people of Latin American origin are currently living in Europe, Chagas disease is not considered as a public health problem, yet. Cases of transmission via blood donation, organ transplantation or from mother-to-child are reported for several European countries but there is no database for Germany. Current epidemiological data are mostly available from regional surveys from other countries or are extrapolated. Hence, there is a large variation in the estimated numbers on the incidence of Chagas. Robust and reliable data are lacking. This review gives an overview on the currently available data and calls for a German Chagas surveillance.

Role of nNOS in cardiac ischemia-reperfusion injury.

Recent studies have consistently demonstrated that neuronal nitric oxide synthase (nNOS) is cardioprotective in different disease states. nNOS has been shown to delay transition to heart failure in response to pressure overload, to protect the myocardium from functional deterioration after myocardial infarction, and to decrease mortality after myocardial infarction. Recent work identified the precise molecular mechanisms of nNOS action in the myocardium during rest and after myocardial damage. In animal models with nNOS overexpression restricted to cardiac myocytes and nNOS(-/-) mice, it was consistently demonstrated that nNOS decreased myocardial contractility via inhibition of the I(Ca,L) amplitude and [Ca(2+)](i) transients. The mitochondria and xanthine oxidoreductase were identified as further targets for nNOS in cardiac disease models. In this review, we focus on the protective effects of nNOS after ischemia-reperfusion injury, with emphasis on the subcellular localization of nNOS and its putative targets.

Inhibition of nuclear translocation of calcineurin suppresses T-cell activation and prevents acute rejection of donor hearts.

BACKGROUND: Inhibition of calcineurin (CnA) activity by cyclosporine A (CsA) is the mainstay in immunosuppressive therapy. CsA inhibits the phosphatase activity of the cytosolic phosphatase CnA and, therefore, prevents the dephosphorylation and subsequently nuclear translocation of the transcription factor nuclear factor of activated T cells (NFAT). However, CsA has multiple other targets within the cell and is, therefore, not specific. We developed a new approach to inhibit CnA/NFAT signaling. This synthetic peptide prevented CnA nuclear translocation in vitro. The purpose of this study was to demonstrate that this novel approach could potentially inhibit T-cell function in vitro and in vivo. METHODS: T-cell activation (Jurkat T cells, naïve rat T cells, and peripheral human T cells) was assessed by protein synthesis, interleukin (IL)-2 promoter activity, and IL-2 levels after T-cell activation. Immunohistological stainings for CnA were performed to investigate nuclear localization of CnA. The immunosuppressive effects in vivo of the synthetic peptide were investigated in rats with heterotopic transplanted hearts. RESULTS: The nuclear localization signal peptide significantly decreased alloantigen-specific T-lymphocyte proliferation, IL-2 promoter activity, and IL-2 production (338% ± 27% vs. 149% ± 11%, n=8, P<0.05) in cultured T cells by inhibition of CnA nuclear translocation. The synthetic peptide also significantly decreased the number of graft infiltrating CD8 T lymphocytes. Moreover, treatment with the synthetic inhibitory inhibited acute graft rejection (5 ± 0.6 days vs. 12 ± 2 days, n=10, P<0.05). CONCLUSIONS: Inhibition of nuclear translocation of CnA is a novel approach to inhibit the activation of the CnA/NFAT signaling cascade. Further studies have to demonstrate the long-term use of this principle in vivo.