Publications by authors named "Sarah M Kamel"

Acoustic emission from the compounds [Fe(HB(tz))] and [Fe(Htrz)(trz)]BF was detected during the thermally induced spin transition and is correlated with simultaneously recorded calorimetric signals. We ascribe this phenomenon to elastic waves produced by microstructural and volume changes accompanying the spin transition. Despite the perfect reversibility of the spin state switching (seen by the calorimeter), the acoustic emission activity decreases for successive thermal cycles, revealing thus irreversible microstructural evolution of the samples.

View Article and Find Full Text PDF

The Santa Barbara Basin is an extraordinary archive of environmental and ecological change, where varved sediments preserve microfossils that provide an annual to decadal record of the dynamics of surrounding ecosystems. Of the microfossils preserved in these sediments, benthic foraminifera are the most abundant seafloor-dwelling organisms. While they have been extensively utilized for geochemical and paleoceanographic work, studies of their morphology are lacking.

View Article and Find Full Text PDF

In some shape-memory single crystals the stress-strain (~) curves, belonging to stress induced martensitic transformations from austenite to martensite at fixed temperature, instead of being the usual slightly increasing function or horizontal, have an overall negative slope with sudden stress drops in it. We discuss this phenomenon by using a local equilibrium thermodynamic approach and analysing the sign of the second derivative of the difference of the Gibbs free energy. We show that, considering also the possible nucleation and growth of two martensite structural modifications/variants, the stress-strain loops can be unstable.

View Article and Find Full Text PDF

There are many systems producing crackling noise (avalanches) in materials. Temporal shapes of avalanches, () ( is the detected voltage signal, is the time), have self-similar behaviour and the normalized () function (e.g.

View Article and Find Full Text PDF

Gain-of-function mutations in the protein-tyrosine phosphatase SHP2 are the most frequently occurring mutations in sporadic juvenile myelomonocytic leukemia (JMML) and JMML-like myeloproliferative neoplasm (MPN) associated with Noonan syndrome (NS). Hematopoietic stem and progenitor cells (HSPCs) are the disease propagating cells of JMML. Here, we explored transcriptomes of HSPCs with SHP2 mutations derived from JMML patients and a novel NS zebrafish model.

View Article and Find Full Text PDF

Background: Cohesinopathies is a term that refers to/covers rare genetic diseases caused by mutations in the cohesin complex proteins. The cohesin complex is a multiprotein complex that facilitates different aspects of cell division, gene transcription, DNA damage repair, and chromosome architecture. Shugoshin proteins prevent the cohesin complex from premature dissociation from chromatids during cell division.

View Article and Find Full Text PDF

Cardiomyopathies are a group of heterogeneous diseases that affect the muscles of the heart, leading to early morbidity and mortality in young and adults. Genetic forms of cardiomyopathy are caused predominantly by mutations in structural components of the cardiomyocyte sarcomeres, the contractile units of the heart, which includes cardiac Troponin T (TnT). Here, we generated mutations with CRISPR/Cas9 technology in the zebrafish gene, encoding cardiac TnT, at a mutational "hotspot" site to establish a zebrafish model for genetic cardiomyopathies.

View Article and Find Full Text PDF

Pheochromocytomas and paragangliomas (PPGLs) caused by mutations in the B-subunit of the succinate dehydrogenase (SDHB) have the highest metastatic rate among PPGLs, and effective systemic therapy is lacking. To unravel underlying pathogenic mechanisms, and to evaluate therapeutic strategies, suitable in vivo models are needed. The available systemic Sdhb knock-out mice cannot model the human PPGL phenotype: heterozygous Sdhb mice lack a disease phenotype, and homozygous Sdhb mice are embryonically lethal.

View Article and Find Full Text PDF

Mutations in genes encoding K channel subunits have been reported for pancreatic disorders and Cantú syndrome. Here, we report a syndrome in six patients from two families with a consistent phenotype of mild intellectual disability, similar facies, myopathy, and cerebral white matter hyperintensities, with cardiac systolic dysfunction present in the two oldest patients. Patients are homozygous for a splice-site mutation in ABCC9 (c.

View Article and Find Full Text PDF

The CXCR3-CXCL11 chemokine-signaling axis plays an essential role in infection and inflammation by orchestrating leukocyte trafficking in human and animal models, including zebrafish. Atypical chemokine receptors (ACKRs) play a fundamental regulatory function in signaling networks by shaping chemokine gradients through their ligand scavenging function, while being unable to signal in the classic G-protein-dependent manner. Two copies of the CXCR3 gene in zebrafish, cxcr3.

View Article and Find Full Text PDF

The zebrafish () has become a popular vertebrate model organism to study organ formation and function due to its optical clarity and rapid embryonic development. The use of genetically modified zebrafish has also allowed identification of new putative therapeutic drugs. So far, most studies have relied on broad overexpression of transgenes harboring patient-derived mutations or loss-of-function mutants, which incompletely model the human disease allele in terms of expression levels or cell-type specificity of the endogenous gene of interest.

View Article and Find Full Text PDF
Article Synopsis
  • * The authors introduce MUSCLEMOTION, an automated, open-source software tool that works with regular lab imaging setups, enabling easy analysis of cardiac contractions and responses to drugs across various experimental models.
  • * MUSCLEMOTION provides accurate measurements of heart movement in different setups, matching the reliability of existing advanced techniques and offering a unified approach to study cardiac diseases and drug effects in both lab and clinical settings.
View Article and Find Full Text PDF