A case of fatal ephedra intake associated with lipofuscin accumulation, caspase activation and cleavage of myofibrillary proteins

Ephedra, a herb reported to suppress appetite and stimulate the sympathetic nervous system as well as cardiac performance, has recently been related to several adverse events, including seizure, stroke, hypertension, myocardial infarction, and sudden death. Here, we describe the case of a 45‐year‐old woman who died of cardiovascular collapse while taking ephedra. Tissue analysis revealed non‐specific degenerative alterations in the myocardium (lipofuscin accumulation, basophilic degeneration and vacuolation of myocytes, as well as myofibrillary loss), associated with myocyte apoptosis, caspase activation, and extensive cleavage of miofibrillary proteins α‐actin, α‐actinin, and cardiac troponin T. Healthcare professionals are therefore urged to warn their patients about the risk of serious adverse effects, which may follow ephedra intake.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/102708/1/ejhf2004-09-012.pd

Incorporation of Organ-Specific MicroRNA Target Sequences to Improve Gene Therapy Specificity:

Thesis advisor: Vassilios BezzeridesThe aim of this study was to utilize a massively parallel reporter assay (MPRA) to identify organ-specific microRNA (miRNA) target sequences to refine the timing and expression of transgene expression for gene therapy. We previously had developed a cardiac gene therapy for Catecholaminergic Polymorphic Ventricular Tachycardia (CPVT) using a systemically delivered adeno-associated virus (AAV9) vector. We hypothesized that incorporation of organ specific miRNA target sites into our vector construct could improve our therapy’s tissue specificity due to the ability of miRNAs to silence transgene expression. Initially, we attempted to incorporate mir-124 target sequences into our vector to detarget the brain. Although these initial attempts were unsuccessful, the study allowed us to develop a protocol to test the effectiveness of miRNA target sequences. Thereafter, we developed a method to screen thousands of putative miRNA target sequences simultaneously. In this study, target sequences of miRNAs specific to the heart, brain and liver were incorporated into a plasmid library. This plasmid library was subsequently made into AAV and injected into mice from a CPVT transgenic line. Total DNA and RNA was later extracted from the target organs, converted into genomic DNA (gDNA) and complementary DNA (cDNA) libraries respectively, and sent for amplicon sequencing. We analyzed the results using Comparative Microbiome Analysis 2.0 software (CoMA) and a custom python script to count the occurrence of each specified barcode per sample. In doing so, we showed that the miRNA suppression mechanism is not only effective but also organ specific. Furthermore, we developed a second script to create a combinatorial library from a set list of miRNA target sequences enabling us to efficiently test thousands of target sequence combinations at once. In doing so, we will be able to identify effective miRNA target sequence combinations to further improve gene therapy specificity.Thesis (BS) — Boston College, 2021.Submitted to: Boston College. College of Arts and Sciences.Discipline: Departmental Honors.Discipline: Biology

Identifying and Quantifying Molecular Species in Biological Samples Using a Multimodal Mass Spectrometry Approach

This item is available only to currently enrolled UTSA students, faculty or staff. To download, navigate to Log In in the top right-hand corner of this screen, then select Log in with my UTSA ID.Mass spectrometry is a versatile analytical tool that can identify, quantify, and even localize an analyte in biological samples. Mass spectrometry has a plethora of applications, but it is often underutilized in fields outside of analytical chemistry. Through optimized method development and utilization of other techniques, multidisciplinary results can be obtained. Cattle fever ticks pose an impending threat to the United States. Through mass spectrometry, current approved macrocyclic lactone-based drugs are quantified using electrospray ionization liquid chromatography tandem mass spectrometry (ESI-LC/MS/MS). The results are used to make recommendations concerning interactions, and efficacy. Additionally, novel drug-targets are probed though matrix-assisted laser desorption/ionization time-of flight mass spectrometry imaging (MALDI-TOF MSI). Peptides are localized and identified on intact tissue sections of cattle fever ticks. The methodology allows for interspecies comparisons, and investigation into mechanisms for drug-resistance. Mass spectrometry can be applied to analysis of other biological matrices. Fatty acid content in skin, and plasma samples can be quantified, and correlated to self-reported pain. The higher the omega-6 fatty acid content, the more sensitive one is to external stimuli. Therefore, the ratio of omega-6 to omega-3 fatty acids are shown to influence pain mechanism pathways, and may contribute to comorbid pain conditions, such as diabetic neuropathy. Aged, dried blood spots contain viable information but are often overlooked. Through optimized sample prep, proteins can be extracted and identified. This provides a baseline for comparison to changes in protein compositions after potential diseases progression. This work bridges the gap between multiple disciplines for more rounded research.Chemistr