Transient ventricular pre-excitation in takotsubo syndrome: Delving in an alternative plausible mechanism

2021 ◽  
Author(s):  
John E. Madias
Keyword(s):  
Takotsubo Syndrome ◽  
Plausible Mechanism

New Procedure for the Highly Regioselective Aerobic Bromination of Aromatic Compounds Using Copper-based Nanocatalyst

2020 ◽  
Vol 17 (3) ◽  
pp. 234-239
Author(s):  
Jalal Albadi ◽  
Mehdi Jalali
Keyword(s):  
Aromatic Compounds ◽  
Plausible Mechanism

A new procedure for the highly regioselective aerobic bromination of aromatic compounds in the presence of copper-based nanoparticles (CuO/ZnO nanocatalyst) under reflux condition is described. Mechanistic parameters are discussed and the plausible mechanism is proposed. Recyclability of the CuO/ZnO nanocatalyst has also been explored upon aerobic bromination of aromatic compounds.

1+1 > 2: Integration of the Host-directed Traditional Chinese Medicine and the Virus-targeted Modern Medicine in Control of COVID-19

2020 ◽  
Vol 7 (2) ◽  
pp. 89-94
Author(s):  
Jianjun Sun
Keyword(s):  
Chinese Medicine ◽  
Traditional Chinese Medicine ◽  
Infectious Diseases ◽  
Modern Medicine ◽  
The World ◽  
Plausible Mechanism

The COVID-19 pandemic has caused millions of infections and hundreds of thousands deaths in the world. The pandemic is still ongoing and no specific antivirals have been found to control COVID-19. The integration of Traditional Chinese Medicine with supportive measures of Modern Medicine has reportedly played an important role in the control of COVID-19 in China. This review summarizes the evidence of TCM in the treatment of COVID-19 and discusses the plausible mechanism of TCM in control of COVID-19 and other viral infectious diseases.

Iodine-Mediated Sulfenylation of Imidazo[1,2-a]pyridines with Ethyl Arylsulfinates

Synlett ◽  
2021 ◽  
Author(s):  
Dong Tang ◽  
Jian Sun ◽  
Yangxiu Mu ◽  
Zafar Iqbal ◽  
Jing Hou ◽  
...  
Keyword(s):  
Reaction Process ◽  
Mild Conditions ◽  
Plausible Mechanism

AbstractA simple iodine-mediated approach is reported for the synthesis of sulfenylated imidazo[1,2-a]pyridines through the reaction of imidazo[1,2-a]pyridines with ethyl arylsulfinates under mild conditions. The reaction scope was investigated, and a plausible mechanism is proposed to elucidate the reaction process and activation mode. The results indicate that ethyl sulfinates are efficient sulfur sources for the construction of C–S bonds.

Digital imaging of the oil permeation mechanism in an oleophobic textile

2021 ◽  
pp. 004051752110069
Author(s):  
Gannian Zhang ◽  
Qinfa Zhang
Keyword(s):  
Pore Size ◽  
Digital Imaging ◽  
Chemical Warfare ◽  
Linear Variation ◽  
Contact Lines ◽  
High Definition ◽  
Effective Protection ◽  
Silicon Oil ◽  
Plausible Mechanism ◽  
Three Stages

Resistance of military clothing to oil permeation is important for effective protection against chemical warfare. In this paper, while a military textile is rendered oleophobic (oil contact angle ≈ 120°) through plasma-assisted deposition of perfluorodecyl acrylate (PFAC8), permeation of the textile by silicon oil is observed. Using high-definition digital imaging, we study the oil permeation dynamics, rationalize the permeation with a plausible mechanism and identify the threshold textile pore size for prevention of the permeation. We find that oil permeates defects of PFAC8 textiles. Our data suggests a linear variation for oil permeation volume ΔV with time t and implies a gravity-driving permeation mechanism. The mechanism comprises three stages involving merging and propagation of oil–yarn contact lines. The threshold pore size dm scales with σ/ P, where σ is the oil surface tension and P is the hydrostatic head exerted by the oil drop. The paper indicates the importance of an undamaged textile structure to ‘robust’ oil resistance.

scholarly journals Cardiac Rupture—The Most Serious Complication of Takotsubo Syndrome: A Series of Five Cases and a Systematic Review

2021 ◽  
Vol 10 (5) ◽  
pp. 1066
Author(s):  
Małgorzata Zalewska-Adamiec ◽  
Hanna Bachórzewska-Gajewska ◽  
Sławomir Dobrzycki
Keyword(s):  
Female Gender ◽  
Left Ventricular ◽  
Cardiac Rupture ◽  
Control Group ◽  
Mechanical Complication ◽  
Takotsubo Syndrome ◽  
St Segment Elevation ◽  
Glucose Levels ◽  
Risk Of Death ◽  
St Segment

Background: The most serious complication of the acute Takotsubo phase is a myocardial perforation, which is rare, but it usually results in the death of the patient. Methods: In the years 2008–2020, 265 patients were added to the Podlasie Takotsubo Registry. Cardiac rupture was observed in five patients (1.89%), referred to as the Takotsubo syndrome with complications of cardiac rupture (TS+CR) group. The control group consisted of 50 consecutive patients with uncomplicated TS. The diagnosis of TS was based on the Mayo Clinic Criteria. Results: Cardiac rupture was observed in women with TS aged 74–88 years. Patients with TS and CR were older (82.20 vs. 64.84; p = 0.011), than the control group, and had higher troponin, creatine kinase, aspartate aminotransferase, and blood glucose levels (168.40 vs. 120.67; p = 0.010). The TS+CR group demonstrated a higher heart rate (95.75 vs. 68.38; p < 0.0001) and the Global Registry of Acute Coronary Events (GRACE) scores (186.20 vs. 121.24; p < 0.0001) than the control group. In patients with CR, ST segment elevation was recorded significantly more often in the III, V4, V5 and V6 leads. Left ventricular free wall rupture was noted in four patients, and in one case, rupture of the ventricular septum. In a multivariate logistic regression, the factors that increase the risk of CR in TS were high GRACE scores, and the presence of ST segment elevation in lead III. Conclusions: Cardiac rupture in TS is rare but is the most severe mechanical complication and is associated with a very high risk of death. The main risk factors for left ventricular perforation are female gender, older age, a higher concentration of cardiac enzymes, higher GRACE scores, and ST elevations shown using electrocardiogram (ECG).

scholarly journals Dynamic Left Intraventricular Obstruction Phenotype in Takotsubo Syndrome

2021 ◽  
Vol 10 (15) ◽  
pp. 3235
Author(s):  
Davide Di Vece ◽  
Angelo Silverio ◽  
Michele Bellino ◽  
Gennaro Galasso ◽  
Carmine Vecchione ◽  
...  
Keyword(s):  
Cardiogenic Shock ◽  
Systolic Function ◽  
Hemodynamic Instability ◽  
Left Ventricular ◽  
Takotsubo Syndrome ◽  
Benign Condition ◽  
Coronary Syndrome ◽  
Lv Dysfunction ◽  
Appropriate Therapy ◽  
Selection Of

Takotsubo syndrome (TTS) is characterized by acute, generally transient left ventricular (LV) dysfunction. Although TTS has been long regarded as a benign condition, recent evidence showed that rate of acute complications and in-hospital mortality is comparable to that of patients with acute coronary syndrome. In particular, the prevalence of cardiogenic shock ranges between 6% and 20%. In this setting, detection of mechanisms leading to cardiogenic shock can be challenging. Besides a severely impaired systolic function, onset of LV outflow tract obstruction (LVOTO) together with mitral regurgitation related to systolic anterior motion of mitral valve leaflets can lead to hemodynamic instability. Early identification of LVOTO with echocardiography is crucial and has important implications on selection of the appropriate therapy. Application of short-acting b1-selective betablockers and prudent administration of fluids might help to resolve LVOTO. Conversely, inotrope agents may increase basal hypercontractility and worsen the intraventricular pressure gradient. To date, outcomes and management of patients with TTS complicated by LVOTO as yet has not been comprehensively investigated.

scholarly journals Ethnic comparison in takotsubo syndrome: novel insights from the International Takotsubo Registry

2021 ◽  
Author(s):  
Yoichi Imori ◽  
Ken Kato ◽  
Victoria L. Cammann ◽  
Konrad A. Szawan ◽  
Manfred Wischnewsky ◽  
...  
Keyword(s):  
Hospital Mortality ◽  
Clinical Characteristics ◽  
Ethnic Disparities ◽  
Japanese Patients ◽  
Learning Approach ◽  
Takotsubo Syndrome ◽  
Unique Identifier ◽  
Hospital Outcomes ◽  
Machine Learning Approach ◽  
The Impact

Abstract Background Ethnic disparities have been reported in cardiovascular disease. However, ethnic disparities in takotsubo syndrome (TTS) remain elusive. This study assessed differences in clinical characteristics between Japanese and European TTS patients and determined the impact of ethnicity on in-hospital outcomes. Methods TTS patients in Japan were enrolled from 10 hospitals and TTS patients in Europe were enrolled from 32 hospitals participating in the International Takotsubo Registry. Clinical characteristics and in-hospital outcomes were compared between Japanese and European patients. Results A total of 503 Japanese and 1670 European patients were included. Japanese patients were older (72.6 ± 11.4 years vs. 68.0 ± 12.0 years; p < 0.001) and more likely to be male (18.5 vs. 8.4%; p < 0.001) than European TTS patients. Physical triggering factors were more common (45.5 vs. 32.0%; p < 0.001), and emotional triggers less common (17.5 vs. 31.5%; p < 0.001), in Japanese patients than in European patients. Japanese patients were more likely to experience cardiogenic shock during the acute phase (15.5 vs. 9.0%; p < 0.001) and had a higher in-hospital mortality (8.2 vs. 3.2%; p < 0.001). However, ethnicity itself did not appear to have an impact on in-hospital mortality. Machine learning approach revealed that the presence of physical stressors was the most important prognostic factor in both Japanese and European TTS patients. Conclusion Differences in clinical characteristics and in-hospital outcomes between Japanese and European TTS patients exist. Ethnicity does not impact the outcome in TTS patients. The worse in-hospital outcome in Japanese patients, is mainly driven by the higher prevalence of physical triggers. Trial Registration URL: https://www.clinicaltrials.gov; Unique Identifier: NCT01947621.

scholarly journals Takotsubo syndrome after mitral valve surgery: a case report

2020 ◽  
Author(s):  
Ana Devesa ◽  
Rafael Hernández-Estefanía ◽  
José Tuñón ◽  
Álvaro Aceña
Keyword(s):  
Mitral Valve ◽  
Fatal Outcome ◽  
Mitral Valve Surgery ◽  
Left Ventricular ◽  
Valve Surgery ◽  
Lv Function ◽  
Partial Recovery ◽  
Takotsubo Syndrome ◽  
Left Circumflex Artery ◽  
Coronary Syndrome

Abstract Background Takotsubo syndrome is a frequent entity; however, it has never been described after a mitral valve surgery. Case summary  We present the case of a 79-year-old woman, with background of atrial fibrillation and a left atrial appendage closure device, who was admitted for elective mitral valve replacement, because of asymptomatic severe primary mitral regurgitation. Biologic mitral valve was implanted without incidences, but in the postoperative, she developed cardiogenic shock. Electrocardiogram (ECG) showed inverted T waves in precordial leads and an echocardiography showed severe left ventricular (LV) dysfunction with mid to distal diffuse hypokinesis, and better contractility in basal segments. Troponin levels were mildly elevated. With the suspicion of a postoperative acute coronary syndrome, a coronary angiography was performed and showed no significant coronary lesions. The haemodynamic situation was compromised for the next 48 h, in which vasoactive support and intra-aortic balloon counterpulsation were implemented. After 48 h, the haemodynamic situation suddenly improved. The ECG was normalized, and a control echocardiogram showed partial recovery of the LV function with resolution of regional wall motion abnormalities. The patient could be discharged at 1 week. The clinical picture was interpreted as a stress cardiomyopathy after mitral valve surgery. Discussion  Takotsubo syndrome is a threatening condition; complications in acute phase could lead to a fatal outcome. Mitral valve surgery has to be considered as a trigger for this entity, after excluding coronary involvement, specially of left circumflex artery.

scholarly journals Be different to be better: the effect of personality on optimal foraging with incomplete knowledge

2021 ◽  
Author(s):  
Poppy M. Jeffries ◽  
Samantha C. Patrick ◽  
Jonathan R. Potts
Keyword(s):  
Optimal Foraging ◽  
Optimal Foraging Theory ◽  
Foraging Strategy ◽  
Foraging Strategies ◽  
Partial Knowledge ◽  
Marginal Value ◽  
Animal Populations ◽  
Plausible Mechanism ◽  
Insight Into ◽  
Modelling Approach

AbstractMany animal populations include a diversity of personalities, and these personalities are often linked to foraging strategy. However, it is not always clear why populations should evolve to have this diversity. Indeed, optimal foraging theory typically seeks out a single optimal strategy for individuals in a population. So why do we, in fact, see a variety of strategies existing in a single population? Here, we aim to provide insight into this conundrum by modelling the particular case of foraging seabirds, that forage on patchy prey. These seabirds have only partial knowledge of their environment: they do not know exactly where the next patch will emerge, but they may have some understanding of which locations are more likely to lead to patch emergence than others. Many existing optimal foraging studies assume either complete knowledge (e.g. Marginal Value Theorem) or no knowledge (e.g. Lévy Flight Hypothesis), but here we construct a new modelling approach which incorporates partial knowledge. In our model, different foraging strategies are favoured by different birds along the bold-shy personality continuum, so we can assess the optimality of a personality type. We show that it is optimal to be shy (resp. bold) when living in a population of bold (resp. shy) birds. This observation gives a plausible mechanism behind the emergence of diverse personalities. We also show that environmental degradation is likely to favour shyer birds and cause a decrease in diversity of personality over time.

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