Identification and study of novel genes expressed in the heart precursor cells

Understanding heart development on a molecular level is a requirement for uncovering the causes of congenital heart diseases. Several genes have been implicated as critical for heart development. However, the inducers of these genes as well as their targets and pathways, remain largely unknown. We have identified a promoter element of chick cCer able to drive EGFP expression in a population of cells that consistently exit from the anterior primitive streak region, from as early as stage HH3+, and that later will populate the heart. Using this promoter element as a tool allowed us to identify novel genes previously not known to potentially play a role in heart development. In order to identify and study genes expressed and involved in the correct development and differentiation of the vertebrate heart precursor cell (HPC) lineages, a differential screening using Affymetrix GeneChip® system technologies was performed. Remarkably, this screening led to the identification of more than 700 transcripts differentially expressed in the heart forming regions (HFR). Bioinformatic tools allowed us to filter the large amount of data generated from this approach and to select a few transcripts for in vivo validation. Five genes were selected for further characterization by whole mount in situ hybridization leading to the validation of their expression in the HPC. From those, Adtk1 and Ccbe1 were selected for functional analysis. Regarding to ccbe1, a more detailed WISH analysis was performed and showed that Ccbe1 is expressed specifically on the cardiac progenitors regions at HH4, more specifically in primary heart field and at later stages is present in the second heart field. Further functional analyses by knockdown and overexpression revealed an important role for Ccbe1 in early heart tube formation. Moreover, the results presented in this thesis suggested that Ccbe1 is a key gene during heart development and might be limited to multipotent and highly proliferative progenitors and downregulated upon cellular commitment into more specific cardiac phenotypes. Other of the genes identified, Adtk1 was also subjected to further functional studies. Knockdown of Adtk1 using morpholino oligonucleotides suggested that it might be necessary for the migration and fusion of the heart tube as well as for neural tube closure.

Liver-like biosensor: immobilized CYP3A4 sensors as tools for ligand binding and enzyme activity measurements

Cytochromes P450 constitute a super-family of enzymes involved in the metabolism of Xenobiotics, where human cytochrome P450 3A4 is the most abundant of all P450s, accounting for about 50% of all human liver cytochromes. This membrane anchored protein is responsible for the metabolization of a wide array of environmental drugs and intoxicants, mainly due to its haem domain properties, and active site cavity volume. These properties make this protein an excellent subject for biosensor application, although CYO3A4 enzyme is also famous for its instability. Enzyme inactivation at room temperature is a normal conversion process that this enzyme undergoes, that may hamper any biosensing approach.

Cradling ashes : a surrealist opera : how music and psychology can function together to express depraved heart syndrome : for countertenor, soprano, tenor, violin, viola, horn in F, piano, and tape.

Original wav file in this record was 0 bytes; re-extracted a new wav file from the CD in Special Collections Nov 2016 and replaced the original wav file in this record.

Predicting Risk of Re-hospitalization for Congestive Heart Failure Patients

Thesis (Master's)--University of Washington, 2012

Functional coherence and annotation agreement metrics for enzyme families

Tese de doutoramento, Informática (Bioinformática), Universidade de Lisboa, Faculdade de Ciências, 2015

Exploring the modulatory role of A2A receptors in oligodendrogenesis derived from neural stem/progenitor cells of the subventricular zone

Tese de mestrado, Neurociências, Faculdade de Medicina, Universidade de Lisboa, 2015

"Heart Music", Symphonic Band, February 14, 2008

Concert program for "Heart Music", Symphonic Band, February 14, 2008

Intervention Recommendations to Minimize the 30-Day Risk-of-Readmission for Heart Failure

Thesis (Master's)--University of Washington, 2015

Structure-inhibition relationship of phenylethanoid glycosides on angiotensin-converting enzyme using ultra-performance liquid chromatography-tandem quadrupole mass spectrometry

Angiotensin-converting enzyme (ACE) plays a critical role in rennin-angiotensin system. Recently, natural products isolated from herbal medicines revealed inhibitory effects against ACE which suggested their potential activities in regulating blood pressure. In this study, ACE inhibition (ACEI) of 21 phenylethanoid glycosides and related phenolic compounds were investigated by measuring the production of HA a rapid, sensitive, accurate and specific ultra-performance liquid chromatography-tandem quadrupole mass spectrometry (UPLC-MS/MS) method. The test compounds showed different inhibitory potencies on ACE ranging from 5.29 to 95.01% at 50 mM, and the compounds with ACEI higher than 50% were selected for further IC50 determination. The IC50 values were from 0.53 ± 0.04 to 15.035 ± 0.036 mM. The structure-inhibition relationship were then explored and the result showed that cinnamoyl groups played an essential role in ACEI of phenylethanoid glycosides. Furthermore, the sub-structures of increasing ACEI for phenylethanoid glycosides is more hydroxyls and less steric hindrance to chelate the active site Zn2+ of ACE. In summary, our results suggested that phenylethanoid glycosides are a widely available source of anti-hypertensive natural products and the information provided from structure-inhibition relationship study could aid the design of structurally modified phenylethanoid glycosides as anti-hypertensive drugs.

Respiratory and non-respiratory sinus arrhythmia: implications for heart rate variability

The quantity of blood arriving at the left side of the heart oscillates throughout the breathing cycle due to the mechanics of breathing. Neurally regulated fluctuations in the length of the heart period act to dampen oscillations of the left ventricular stroke volume entering the aorta. We have reported that stroke volume oscillations but not spectral frequency variability stroke volume measures can be used to estimate the breathing frequency. This study investigated with the same recordings whether heart period oscillations or spectral heart rate variability measures could function as estimators of breathing frequency. Continuous 270 s cardiovascular recordings were obtained from 22 healthy adult volunteers in the supine and upright postures. Breathing was recorded simultaneously. Breathing frequency and heart period oscillation frequency were calculated manually, while heart rate variability spectral maximums were obtained using heart rate variability software. These estimates were compared to the breathing frequency using the Bland–Altman agreement procedure. Estimates were required to be \±10% (95% levels of agreement). The 95% levels of agreement measures for the heart period oscillation frequency (supine: -27.7 to 52.0%, upright: -37.8 to 45.9%) and the heart rate variability spectral maximum estimates (supine: -48.7 to 26.5% and -56.4 to 62.7%, upright: -37.8 to 39.3%) exceeded 10%. Multiple heart period oscillations were observed to occur during breathing cycles. Both respiratory and non-respiratory sinus arrhythmia was observed amongst healthy adults. This observation at least partly explains why heart period parameters and heart rate variability parameters are not reliable estimators of breathing frequency. In determining the validity of spectral heart rate variability measurements we suggest that it is the position of the spectral peaks and not the breathing

The ubiquitin editing enzyme A20 maintains immune homeostasis and prevents autoimmunity

Dissertation presented to obtain the Doctorate degree (Ph.D.) in Biology at Instituto de Tecnologia Química e Biológica da Universidade Nova de Lisboa

The Hybrid Approach for Palliation of Hypoplastic Left Heart Syndrome: Intermediate Results of a Single-Center Experience

INTRODUCTION: Hypoplastic left heart syndrome (HLHS) is a major cause of cardiac death during the first week of life. The hybrid approach is a reliable, reproducible treatment option for patients with HLHS. Herein we report our results using this approach, focusing on its efficacy, safety and late outcome. METHODS: We reviewed prospectively collected data on patients treated for HLHS using a hybrid approach between July 2007 and September 2014. RESULTS: Nine patients had a stage 1 hybrid procedure, with seven undergoing a comprehensive stage 2 procedure. One patient completed the Fontan procedure. Five patients underwent balloon atrial septostomy after the hybrid procedure; in three patients, a stent was placed across the atrial septum. There were three deaths: two early after the hybrid procedure and one early after stage two palliation. Overall survival was 66%. CONCLUSIONS: In our single-center series, the hybrid approach for HLHS yields intermediate results comparable to those of the Norwood strategy. The existence of dedicated teams for the diagnosis and management of these patients, preferably in high-volume centers, is of major importance in this condition.

Synthesis of new enzyme stabilisers inspired by compatible solutes of hyperthermophilic microorganisms

Dissertation presented to obtain the Ph.D degree in Engineering Sciences and Technology.