History and electrocardiography as pathway to diagnosis of Brugada syndrome: a case report

Introduction: The major electrocardiographic feature of Brugada syndrome is a distinct ST-segment elevation in the right precordial leads. Patients with spontaneously emerging Brugada ECG have a high risk of sudden arrhythmic death secondary to ventricular tachycardia/fibrillation. The ECG manifestations of Brugada syndrome are often dynamic. Type 1 pattern is diagnostic of Brugada syndome and is characterized by a coved ST segment elevation ≥2 mm, followed by a negative T wave.1-3 Case report: 23-years-old male has been hospitalized due to piercing pain in the left hemithorax and chills and fever lasting for several hours. He experienced such complaints for the first time in his life. He does not use tobacco, alcohol or psychoactive substances. He plays football for recreation. He reported severe family history: his father died at age of 36, and two paternal uncles died before their age of 25. At admission, he is conscious, oriented, mildly dyspneic, febrile (39.8˚C); BP 115/70 mmHg. Laboratory: WBC 13.9 x 109/L, neutrophils 85%, CRP 87; urine culture showed Escherichia coli >100.000/ mL. He has been treated with antipyretic/paracetamol, antibiotic according to antibiogramme, and rehydration therapy. The initial ECG showed type 1 Brugada sign: cove ST elevation in V1-3 with negative T waves; RBBB (Figure 1). After a 12 hours of hospitalization, the ECG showed type 2 Brugada sign: saddle-shaped elevation of ST-segment and J point in V2 (Figure 2). After 24 hours of hospitalization, the ECG showed type 3 Brugada sign (Figure 3). At discharge 7 days later, type 1 Brugada sign develops again – a cove ST elevation in V1-2 and a saddle ST elevation in V3 (Figure 4). Ajmaline test has been performed according to protocol. During administration of a maximum dose of 70 mg, a >2 mm ST elevation was detected in V2-3, making the test positive. Electrophysiological study involved right femo-ral vein access with quadripolar catheter to the right ventricle. Programmed stimulation did not induce ventricular tachycardia/ fibrillation. The patient was not indicated for ICD for prevention of sudden cardiac death. Conclusion: Family history and electrocardiography are the cornerstones of diagnosis of Brugada syndrome even today. Hyperthermia helped damask typical type 1 Brugada sign that showed dynamic changes. Our patient did not meet the criteria for implantation of ICD device

Spontaneous coronary artery dissection: a case report

Introduction: Spontaneous coronary artery dissection (SCAD) is a rare cause of acute coronary syndrome. Some of the predisposing factors for SCAD are atherosclerosis, peripartum period, inflammatory and connective tissue disorders, heavy exercise, and certain drugs (oral contraceptives, cocaine, etc.).1,

Raman scattering by coupled plasmon-LO phonons in InN nanocolumns

Raman measurements on high quality, relaxed InN nanocolumns grown on Si(001) and Si(111) substrates by plasma-assisted molecular beam epitaxy are reported. A coupled LO phonon-plasmon mode around 430 cm-1, together with the uncoupled LO phonon appears in the nanocolumnar samples. The coupled mode is attributed to spontaneous accumulation of electrons at the lateral surfaces of the nanocolumns, while the uncoupled phonon originates from their inner part. Infrared reflectance measurements confirm the presence of electrons in the nanocolumns. The electron density in the accumulation layer depends on the growth temperature and is sensitive to exposure of HCl. Our results indicate that accumulation of intrinsic electrons occurs not only at the polar surfaces of InN layers, but also on non-polar lateral surfaces of InN nanocolumns. Its origin is attributed to an In-rich surface reconstruction of the nanocolumns sidewalls

Resonant Raman-active localized vibrational modes in AlyGa{1-y}NxAs{1-x} alloys: Experiment and firstprinciples calculations

The localized vibrational modes associated with substitutional aluminium and nitrogen atoms in AlyGa1−yNxAs1−x have been studied within first-principles density functional theory using a supercell approach. Localized vibrational modes related to N-AlmGa4−m (1≤m≥4) complexes have been identified, which reveal the formation of N-Al4 units well above random abundance, in qualitative agreement with a large calculated value (391 meV) of the Al-N bond formation energy. We determine the resonant Raman-active modes from the selection rule obtained by calculating the electron-phonon coupling strength and optical transition matrix elements and compare them with resonant Raman spectroscopy measurements. The localized modes from Raman scattering measurements with frequencies around 325, 385, 400, 450, 500, and 540 cm−1 are found to be in good agreement with the calculated modes (326, 364, 384, 410, 456, 507, and 556 cm−1). The modes are classified as follows: the two modes at 326 and 556 cm−1 belong to the N-AlGa3 configuration; there are three modes which belong to N-Al2Ga2 with frequencies at 326, 364, and 507 cm−1; the N-Al3Ga configuration gives rise to modes whose frequencies are 384 and 456 cm−1; and the mode at a frequency of 410 cm−1 belongs to the N-Al4 complex. The comparison of line intensities from samples before and after rapid thermal annealing allows us to experimentally distinguish vibrational modes associated with different clusters, in agreement with the theoretical assignments

Multidimensional acoustic analysis of pathological voice

Introduction There are subjective and objective ways to examine the effects of vocal therapy in voice disorders. The most precise and objective check-up is the use of computer voice analysis. Objective The aim of the research was to perform a detailed analysis of acoustic structure of the vowel A before and after voice treatment in patients with vocal fold nodules in order to obtain objective verification of the vocal rehabilitation success. Methods We examined 30 female patients, aged 34.6 +/- 6.69 years, with vocal fold nodules. Acoustic parameters of voice were compared with the control group consisting of 21 subjects without voice pathology. In all persons the vowel A was recorded and analyzed before and after a month of vocal therapy. The success of the vocal therapy was tracked using computer analysis of vocal structure. Signal, noise and tremor parameters were processed. Results Of the analyzed vowel A parameters: STD, PER, JITA, JITT, RAP, vFO, ShdB, SHIM, APQ, VTI, SPI, F0, NHR, FTRI, eleven improved (p lt 0.05 and p lt 0.01). Three parameters (F0, NHR, FTRI) changed showing improvement, but the obtained differences were not statistically significant (p > 0.05). Conclusion Based on the obtained results it was concluded that vocal therapy gave satisfactory results, but that it should be continually applied until full stabilization of the voice

Identification of sterile cytoplasm (CMS) in maize by using specific mtDNA primers

Thirty sources of cytoplasmic male sterility (CMS) from Maize Gene Bank "Zemun Polje", distributed among Yugoslav OP varieties, have been tested for the presence of particular type of cytoplasm by a single seed multiplex PCR approach with specific primer pairs for T, C and S type cytoplasm. Combination of three pairs of primers in a single PCR reaction, corresponding to the chimeric regions of mtDNA sequences specific for each type of CMS, allowed reliable identification of the major CMS types. Dominant presence of S type cytoplasm was detected. For sources where there is no clear identification of the type of CMS (absence of the PCR band) there is a reasonable doubt that it could be a new, yet unidentified type of CMS.Trideset izvora citoplazmatične muške sterilnosti (CMS) u okviru lokalnih populacija iz Banke gena Instituta za kukuruz "Zemun Polje" je testirano na prisustvo odgovarajućeg tipa citoplazme multipleks PCR metodom, korišćenjem specifičnih prajmera za T, C i S citoplazmu. Kombinovanje tri para prajmera u jednoj PCR reakciji, koji odgovaraju himernim regionima mitohondrijalnih DNK sekvenci specifičnih za svaki tip citoplazme, omogućilo je pouzdanu identifikaciju glavnih tipova sterilne citoplazme. Detektovano je dominantno prisustvo S tipa citoplazme. Za izvore sterilnosti kod kojih nije identifikovan tip sterilne citoplazme (odsustvo PCR trake) postoji realna sumnja da se radi o novim, neidentifikovanim tipovima citoplazmatične muške sterilnosti

Direct visualization and effects of atomic-scale defects on the optoelectronic properties of hexagonal boron nitride

This is the peer reviewed version of the following article: Advanced Electronic Materials 7.7 (2021): 2001177 which has been published in final form at https://doi.org/10.1002/aelm.202001177. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Version