Myocardial energy depletion and dynamic systolic dysfunction in hypertrophic cardiomyopathy

Evidence indicates that anatomical and physiological phenotypes of hypertrophic cardiomyopathy (HCM) stem from genetically mediated, inefficient cardiomyocyte energy utilization, and subsequent cellular energy depletion. However, HCM often presents clinically with normal left ventricular (LV) systolic function or hyperkinesia. If energy inefficiency is a feature of HCM, why is it not manifest as resting LV systolic dysfunction? In this Perspectives article, we focus on an idiosyncratic form of reversible systolic dysfunction provoked by LV obstruction that we have previously termed the 'lobster claw abnormality' — a mid-systolic drop in LV Doppler ejection velocities. In obstructive HCM, this drop explains the mid-systolic closure of the aortic valve, the bifid aortic pressure trace, and why patients cannot increase stroke volume with exercise. This phenomenon is characteristic of a broader phenomenon in HCM that we have termed dynamic systolic dysfunction. It underlies the development of apical aneurysms, and rare occurrence of cardiogenic shock after obstruction. We posit that dynamic systolic dysfunction is a manifestation of inefficient cardiomyocyte energy utilization. Systolic dysfunction is clinically inapparent at rest; however, it becomes overt through the mechanism of afterload mismatch when LV outflow obstruction is imposed. Energetic insufficiency is also present in nonobstructive HCM. This paradigm might suggest novel therapies. Other pathways that might be central to HCM, such as myofilament Ca2+ hypersensitivity, and enhanced late Na+ current, are discussed

An input–output model of exchange-rate pass-through

The impact of the exchange rate on price formation is often debated through a mechanism called the exchange-rate pass-through. Studies of the pass-through generally rely on econometric analysis implemented on time series data. This study examines pass-through to the domestic price level through an input–output model. The proposed model is implemented on a sample of countries, and a number of different variables connected to the pass-through are examined. A comparison across countries and sectors highlights the importance of the construction sector in price formation. National income is negatively related to the pass-through. A high dependence on intermediate imports implies higher pass-through. Price level volatility and pass-through are positively related; whereas a country’s monetary policy stance has no apparent effect. The effect of exchange-rate volatility is unclear; it is negative for the real effective exchange rate, the connection is very weak in the case of the nominal exchange rate. © 2017, © 2017 The International Input–Output Association

Does scapular elevation occur with glenohumeral flexion and abduction? a study through open magnetic resonance imaging and autopsy

Objectives: This study aims to reveal whether there is an elevation in scapula during flexion and abduction of the glenohumeral joint. Patients and methods: In the first stage of our study 32 subjects were randomly divided into two groups. The mobility of the scapular notch was examined using open magnetic resonance imaging (MRI) assay when the glenohumeral joint was in flexion in the first group (5 males, 10 females; mean age 21.1 years; range 18 to 24 years) and in abduction in the second group (8 males, 9 females; mean age 22.1 years; range 18 to 27 years) and the motion range was found to be between 0 and 150 degrees. In the second stage of our study, the mobilities of the scapular notch was examined on autopsy during passive humeral mobility. Results: According to the open MRI results, there was no elevation or depression during the passive flexion and abduction of the glenohumeral joint. While the scapular notch migrated slightly to the medial side during abduction of the glenohumeral joint, it did not move during flexion. Also in an autopsy study, we observed that scapula did not move in vertical direction during the glenohumeral abduction and flexion mobilities. Conclusion: There is no vertical mobility in the scapula during glenohumeral flexion and abduction. Also, there is no medial mobility during flexion except during abduction

Geological features and geochemical characteristics of Late Devonian-Early Carboniferous K-bentonites from northwestern Turkey

Newly discovered K-bentonite beds, interstratified with limestones/dolomitic limestones of the Upper Devonian-Lower Carboniferous Yilanli Formation, are exposed in the northwestern Black Sea region of Turkey, around Zonguldak and Bartin. K-bentonite samples collected from four different locations: the Gavurpinari and Yilanli Burnu quarries from the Bartin area, the Cimsir Cukurlari quarry from the Sapca area, and the Gudullu and Gokgol highway tunnel section near Zonguldak city were investigated using optical microscopy, X-ray diffraction and inductively coupled plasma mass spectrometry in order to reveal their mineralogical and geochemical characteristics and understand their origin and evolution. The K-bentonites occur at different levels in the Yilanli Formation as 2-40 cm-thick, greenish to yellowish beds cropping out several hundred metres along strike. Preliminary biostratigraphic data suggest that the protoliths of the Bartin (Gavurpinari and Yilanli Burnu) and Gudullu K-bentonites were deposited at around the boundary between the Frasnian and Famennian, whereas those in the Sapca and Gokgol sections are slightly younger (Devonian-Carboniferous boundary interval). The lithofacies types of the host carbonate rocks suggest an 'epeiric' shallow carbonate platform environment. Illite and mixed-layer illite-smectite were the major clay minerals in the K-bentonites. The K-bentonites from the Bartin area display a high degree of illitization and consist mainly of illite indicating high-grade diagenesis, whereas illite-smectite-rich samples from the Sapca and Gokgol tunnel locations reflect relatively lower diagenetic conditions. According to their geochemical compositions, two groups of K-bentonites were distinguished, one with alkali basalt (Bartin area and Gudullu locations) and one with trachyte affinities (Gokgol tunnel and Sapca locations). Geochemical fingerprinting of K-bentonites by trace and rare earth element (REE) data suggest that tephras with alkali basalt composition have been derived by a source formed in a 'continental back-arc' setting, whereas the source of K-bentonites with trachytic precursors is related to 'continental within-plate rifting'. An evaluation of the global Late Devonian and Devonian-Carboniferous volcanism suggests that the bentonite precursors may be related to late-Variscan magmatism in Laurussia