Takotsubo syndrome and atrial myxoma-identifying a new trigger: a case report.

Takotsubo syndrome (TTS) is a rare cardiomyopathy, but its prevalence is increasing due to the greater availability of diagnostic tools, whose pathophysiology is unknown; however, the evidence points to an excess of catecholamines that ends up generating cardiac stunning. The cause of excessive sympathetic discharge is multifactorial, and some tumors may be related to their origin. In this case report, we present a female patient with TTS whose only identified triggering factor was an atrial myxoma, which generated an unusual clinical presentation. Current multimodal diagnostic tools together with the multidisciplinary evaluation of the HeartTeam allowed an accurate diagnosis and an adequate management of the clinical picture.

Removal of arsenic and methylene blue from water by granular activated carbon media impregnated with zirconium dioxide nanoparticles.

This study investigated the effects of in situ ZrO(2) nanoparticle formation on properties of granulated activated carbon (GAC) and their impacts on arsenic and organic co-contaminant removal. Bituminous and lignite based zirconium dioxide impregnated GAC (Zr-GAC) media were fabricated by hydrolysis of zirconium salt followed by annealing of the product at 400 °C in an inert environment. Media characterization suggested that GAC type does not affect the crystalline structure of the resulting ZrO(2) nanoparticles, but does affect zirconium content of the media, nanoparticle morphology, nanoparticle distribution, and surface area of Zr-GAC. The arsenic removal performance of both media was compared using 5mM NaHCO(3) buffered ultrapure water and model groundwater containing competing ions, both with an initial arsenic C(0) ≈ 120 µg/L. Experimental outcomes suggested favorable adsorption energies and higher or similar adsorption capacities than commercially available or experimental adsorbents when compared on the basis of metal content. Short bed adsorber column tests showed that arsenic adsorption capacity decreases as a result of kinetics of competing ions. Correlation between the properties of the media and arsenic and methylene blue removal suggested that surface area and GAC type may be the dominant factors controlling the arsenic and organic co-contaminant removal performance of the fabricated Zr-GAC media.

Microhomologies between T-DNA ends and target sites often occur in inverted orientation and may be responsible for the high frequency of T-DNA-associated inversions.

Sequence analysis of left and right border integration sites of independent, single-copy T-DNA inserts in Arabidopsis thaliana revealed three previously unrecognized concomitants of T-DNA integration. First, genomic pre-insertion sites shared sequence similarity not only with the T-DNA left and right border regions, as was previously reported, but also at high frequency with the inverted complement of the T-DNA right border region. Second, palindromic sequences were frequently found to overlap or lie adjacent to genomic target sites, suggesting a high recombinogenic potential for palindromic elements during T-DNA integration and a possible role during the primary contact between the T-DNA and the target DNA. Third, "filler" DNA sequences between genomic pre-insertion site DNA and T-DNA often derive from sequences in the T-DNA left and right border regions that are clustered around palindromic sequences in these T-DNA regions, suggesting that these palindromic elements are "hot spots" for filler DNA formation. The discovery of inverted sequence similarities at the right border suggests a previously unrecognized mode of T-DNA integration that involves heteroduplex formation at both T-DNA borders and with opposite strands of the target DNA. Scanning for sequence similarities in both direct and inverted orientation may increase the probability and/or effectiveness of anchoring the T-DNA to the target DNA. Variations on this scheme may also account for inversion events at the target site of T-DNA integration and inverted T-DNA repeat formation, common sequence organization patterns associated with T-DNA integration.

Systemic lupus erythematosus in three ethnic groups. XVIII. Factors predictive of poor compliance with study visits.

OBJECTIVE: To determine the baseline factors predictive of poor compliance with study visits in a longitudinal multiethnic lupus cohort study. METHODS: Patients with systemic lupus erythematosus (n = 344) representing a total of 2,069 potential study visits were studied. Of the participants, 24.4% were Hispanic, 43.3% African American, and 32.3% Caucasian. Noncompliance was defined as missing 2 or more study visits. For the purpose of these analyses, visits completed only by review of medical records were considered missing. Baseline socioeconomic-demographic, clinical, and psychosocial features between compliant and noncompliant patients were compared. Variables with P < 0.10 were then entered into a multivariable logistic regression analysis with compliance being the dependent variable. RESULTS: There were 178 compliant and 166 noncompliant patients. Noncompliant patients were more likely to be young, unmarried, of African American ethnicity, live closer to the medical centers, and have longer disease duration and greater disease activity as assessed by the physician than the compliant patients. In the multivariable model, longer disease duration (P = 0.010), higher level of disease activity (P = 0.009), and shorter distance to travel to study visits (P = 0.046) were predictors of noncompliance; their odds ratios and confidence intervals were below 1. CONCLUSIONS: We have identified baseline patient characteristics that may predict noncompliance with study visits (disease duration, disease activity, and distance to the medical center). This information will serve as the basis for developing interventions to curtail noncompliance. Our data may have applicability in other lupus cohort studies.

Identification of a novel glucocorticoid receptor mutation in budesonide-resistant human bronchial epithelial cells.

We developed a molecular genetic model to investigate glucocorticoid receptor (GR) signaling in human bronchial epithelial cells in response to the therapeutic steroid budesonide. Based on a genetic selection scheme using the human Chago K1 cell line and integrated copies of a glucocorticoid-responsive herpes simplex virus thymidine kinase gene and a green fluorescent protein gene, we isolated five Chago K1 variants that grew in media containing budesonide and ganciclovir. Three spontaneous budesonide-resistant subclones were found to express low levels of GR, whereas two mutants isolated from ethylmethane sulfonate-treated cultures contained normal levels of GR protein. Analysis of the GR coding sequence in the budesonide-resistant subclone Ch-BdE5 identified a novel Val to Met mutation at amino acid position 575 (GRV575M) which caused an 80% decrease in transcriptional regulatory functions with only a minimal effect on ligand binding activity. Homology modeling of the GR structure in this region of the hormone binding domain and molecular dynamic simulations suggested that the GRV575M mutation would have a decreased affinity for the LXXLL motif of p160 coactivators. To test this prediction, we performed transactivation and glutathione-S-transferase pull-down assays using the p160 coactivator glucocorticoid interacting protein 1 (GRIP1)/transcriptional intermediary factor 2 and found that GRV575M transcriptional activity was not enhanced by GRIP1 in transfected cells nor was it able to bind GRIP1 in vitro. Identification of the novel GRV575M variant in human bronchial epithelial cells using a molecular genetic selection scheme suggests that functional assays performed in relevant cell types could identify subtle defects in GR signaling that contribute to reduced steroid sensitivities in vivo.