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Jayson Lian, Nicole Levine, Woojin Cho
PURPOSE: To review the current literature on methods of accurate numeration of vertebral segments in patients with Lumbosacral transitional vertebrae (LSTVs). LSTVs are a common congenital anomaly of the L5-S1 junction. While their clinical significance has been debated, unquestionable is the need for their identification prior to spinal surgery. We hypothesize that there are no reliable landmarks by which we can accurately number transitional vertebrae, and thus a full spinal radiograph is required...
March 21, 2018: European Spine Journal
Zahra Rostami, Sajad Jafari
Complex anatomical and physiological structure of an excitable tissue (e.g., cardiac tissue) in the body can represent different electrical activities through normal or abnormal behavior. Abnormalities of the excitable tissue coming from different biological reasons can lead to formation of some defects. Such defects can cause some successive waves that may end up to some additional reorganizing beating behaviors like spiral waves or target waves. In this study, formation of defects and the resulting emitted waves in an excitable tissue are investigated...
April 2018: Cognitive Neurodynamics
Aparajita Banerjee, Björn Hamberger
Catalyzing stereo- and regio-specific oxidation of inert hydrocarbon backbones, and a range of more exotic reactions inherently difficult in formal chemical synthesis, cytochromes P450 (P450s) offer outstanding potential for biotechnological engineering. Plants and their dazzling diversity of specialized metabolites have emerged as rich repository for functional P450s with the advances of deep transcriptomics and genome wide discovery. P450s are of outstanding interest for understanding chemical diversification throughout evolution, for gaining mechanistic insights through the study of their structure-function relationship, and for exploitation in Synthetic Biology...
2018: Phytochemistry Reviews: Proceedings of the Phytochemical Society of Europe
Jun Muratsu, Masahiro Koseki, Daisaku Masuda, Yuji Yasuga, Satoki Tomoyama, Keiji Ataka, Yoshiki Yagi, Atsushi Nakagawa, Hidehumi Hamada, Shigeki Fujita, Hiroaki Hattori, Tohru Ohama, Makoto Nishida, Hisatoyo Hiraoka, Yuji Matsuzawa, Shizuya Yamashita
We report a case of Tangier disease with Leriche syndrome and bleeding tendency. In this male patient, nasal hemorrhage had been observed frequently throughout childhood. At 46 years old, he experienced effort angina, and coronary angiography demonstrated 75% stenosis in the right coronary artery. Orange-colored tonsils, mild hepatosplenomegaly and very low levels of serum high-density lipoprotein cholesterol (HDL-C) were observed, and the patient was diagnosed with Tangier disease. At 52 years old, effort angina recurred...
March 20, 2018: Journal of Atherosclerosis and Thrombosis
Jung Ho Ko, Young-Joon Kim, Hyun Ho Jung
A 24-year-old man was admitted with sudden severe headache. Brain computed tomography (CT) revealed a subarachnoid hemorrhage in the basal cistern and both Sylvian cisterns and a left internal carotid artery angiogram showed a small aneurysm on the bifurcation of the left middle cerebral artery. We performed Y-configured stent-assisted coil embolization. On the fifth post-embolization day, the patient had chills, and his body temperature was over 38℃. Staphylococcus aureus was cultured from the venous blood sample...
January 1, 2018: Interventional Neuroradiology
Antonio Bauzá, Antonio Frontera
In this manuscript, we combined a search in the Cambridge Structural Database (CSD) and ab initio calculations (RI-MP2/def2-TZVPD level of theory) to analyze the ability of trisulphide and triselenide moieties to establish chalcogen 'like-like' interactions. A preliminary CSD inspection revealed two predominant structural patterns, depending on the anti or syn conformation adopted by the substituents of the S₃/Se₃ bridge, leading to bifurcated or double chalcogen bonding interactions, respectively. In order to analyze these two relevant structural motifs we have used a series of S and Se derivatives Ch₃X₂ (Ch = S and Se and X = H, F, CN, and CF₃) which act as both electron donor (using the lone pairs) and acceptor (using the σ-holes) entities...
March 19, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Wolfgang Buckel, Rudolf K Thauer
There are two types of electron bifurcation (EB), either quinone- or flavin-based (QBEB/FBEB), that involve reduction of a quinone or flavin by a two-electron transfer and two reoxidations by a high- and low-potential one-electron acceptor with a reactive semiquinone intermediate. In QBEB, the reduced low-potential acceptor (cytochrome b) is exclusively used to generate ΔμH+ . In FBEB, the "energy-rich" low-potential reduced ferredoxin or flavodoxin has dual function. It can give rise to ΔμH+ /Na+ via a ferredoxin:NAD reductase (Rnf) or ferredoxin:proton reductase (Ech) or conducts difficult reductions such as CO2 to CO...
March 21, 2018: Chemical Reviews
Yimy Amarillo, Angela Isabel Tissone, German Mato, Marcela S Nadal
Slow repetitive burst firing by hyperpolarized thalamocortical (TC) neurons correlates with global slow rhythms (< 4 Hz), which are the physiological oscillations during N-REM sleep, or pathological ones during idiopathic epilepsy. The pacemaker activity of TC neurons depends on the expression of several subthreshold conductances, which are modulated in a behaviorally dependent manner. Here we show that up-regulation of the small and neglected inward rectifier potassium current IKir induces repetitive burst firing at slow and delta frequency bands...
March 21, 2018: Journal of Neurophysiology
Karl N Blodgett, Xiao Zhu, Patrick S Walsh, Dewei Sun, Jaeyeon Lee, Soo Hyuk Choi, Timothy S Zwier
The folding propensities of a capped, cyclically constrained, mixed <i>α</i>/<i>β</i>-diastereomer pair, (<i>SRSS</i>) Ac-Ala-<i>β</I><sub>ACHC</sub>-Ala-NHBn (hereafter <i>RS</i>) and (<i>SSRS</i>) Ac-Ala-<i>β</I><sub>ACHC</sub>-Ala-NHBn (<i>SR</i>), have been studied in a molecular beam using single-conformation spectroscopic techniques. These <i>α</i>/<i>β</i>-tripeptides contain a cyclohexane ring across each C<sub><i>α</i></sub>-C<sub><i>β</i></sub> bond, at which positions their stereochemistries differ...
March 20, 2018: Journal of Physical Chemistry. A
Yoav Yaakov Biton
The statistical mechanics of a short circularized DNA molecule, a DNA minicircle, with prescribed linking number depends heavily on the mechanical and geometrical properties of the DNA, which are known to be functions of the sequence. A description of a general numerical scheme used for our advanced simulation is presented with examples that reveal the effects of sequence dependence and local deformations, caused by protein binding, on the configurations in a canonical ensemble of a supercoiled minicircle. Using a realistic course grain model in which the sequence-dependent elasticity, the intra-molecular electrostatic interactions, and the impenetrability of the DNA molecule are taken into account, we show the bifurcation of equilibria of supercoiled minicircle DNA with the induced bending as a parameter...
March 20, 2018: Journal of Chemical Theory and Computation
K Schneider
The radiographic technique of pediatric chest X‑rays is substantially different from that in adults. In nearly all cases ap/pa X‑rays are sufficient and lateral radiographs are rarely needed. In the first years of life the thymus may overshadow the heart, the great vessels and the lung hila. The most important anatomical structures essential for diagnosing pathological findings of the lungs and mediastinum are the trachea with the bifurcation and the main bronchi with the adjacent great vessels. For the assessment of distended lungs and intrathoracic consolidations, fundamental knowledge of the anatomy in childhood and malformations which can involve the airways, the lungs, the heart, as well as systemic and pulmonary vessels are indispensable...
March 19, 2018: Der Radiologe
P Lylyk, J Chudyk, C Bleise, H Henkes, P Bhogal
BACKGROUND: Recently, numerous devices dedicated to the treatment of wide-necked aneurysms have become available. We present our initial experience with the pCANvas device and present the technical success rate, clinical outcome and immediate angiographic occlusion rates. OBJECTIVE: We sought to determine the efficacy of flow with the pCANvas for the treatment of unruptured intracranial aneurysms. METHODS: We performed a retrospective review of our prospectively collected data to identify patients treated with the pCANvas device between February 2015 and February 2017...
March 19, 2018: Clinical Neuroradiology
Yan Zhang, Hong Li, Yingqin Jia, Pengfei Yang, Feng Zhao, Wei Wang, Wenqing Liu, Guisheng Chen, Xiaoqing Zhuang, Juan Li
BACKGROUD: Vascular calcification is currently recognized as an important pathobiological process in atherosclerosis, but the mechanism remains elusive. Given the similarities in vascular calcification and bone formation,18 F-sodium fluoride (18 F-NaF) is now considered a novel marker of vascular calcification. This study aimed to correlate18 F-NaF accumulation with the histological characterization of vascular calcification in carotid plaques. METHODS: A total of 8 patients who were undergoing carotid endarterectomy (CEA) for carotid artery stenosis were recruited...
March 16, 2018: Journal of Stroke and Cerebrovascular Diseases: the Official Journal of National Stroke Association
Tomotaka Ohshima, Shigeru Miyachi, Naoki Matsuo, Reo Kawaguchi, Aichi Niwa, Ryuya Maejima, Taiki Isaji, Masakazu Takayasu
BACKGROUND AND PURPOSE: We report a secure endovascular approach for the treatment of vascular lesions of the posterior circulation. Even if a large profile guide catheter is wedged in the unilateral vertebral artery (VA), our VA flow reversal method can prevent ischemic complications, including the spinal cord infarction. CASE PRESENTATION: The patient was a 64-year-old woman who had been followed up for arteriovenous malformation (AVM) and an unruptured aneurysm of the basilar artery-superior cerebellar artery bifurcation...
March 16, 2018: Journal of Stroke and Cerebrovascular Diseases: the Official Journal of National Stroke Association
Jared A Grummer, Mariana M Morando, Luciano J Avila, Jack W Sites, Adam D Leaché
Rapid evolutionary radiations are difficult to resolve because divergence events are nearly synchronous and gene flow among nascent species can be high, resulting in a phylogenetic "bush". Large datasets composed of sequence loci from across the genome can potentially help resolve some of these difficult phylogenetic problems. A suitable test case is the Liolaemus fitzingerii species group of lizards, which includes twelve species that are broadly distributed in Argentinean Patagonia. The species in the group have had a complex evolutionary history that has led to high morphological variation and unstable taxonomy...
March 16, 2018: Molecular Phylogenetics and Evolution
François Dérimay, Gérard Finet, Geraud Souteyrand, Luc Maillard, Adel Aminian, Benoit Lattuca, Guillaume Cayla, Guillaume Cellier, Pascal Motreff, Gilles Rioufol
AIMS: A new coronary bifurcation provisional stenting technique without kissing balloon, rePOT, associating proximal optimizing technique (POT), side-branch inflation and final POT, showed excellent mechanical results in a bench test. The present study sought to use optical coherence tomography (OCT) to quantify the mechanical results of rePOT in vivo in a large patient sample with complex coronary bifurcations. METHODS AND RESULTS: 106 patients with coronary bifurcations were included in a multicenter prospective registry (left main, 40...
March 20, 2018: EuroIntervention
Zilun Li, Henghui Yin, Mian Wang, Ridong Wu, Chenshu Liu, Chen Yao, Guangqi Chang
PURPOSE: To report the use of the octopus endograft technique to treat a patient with a ruptured thoracoabdominal aortic aneurysm (TAAA). CASE REPORT: A 46-year-old man was diagnosed with a contained rupture of a 9-cm type V TAAA. The presence of an occluded superior mesenteric artery (SMA), a stenotic celiac trunk, an enlarged inferior mesenteric artery (IMA), and rich collaterals with the SMA and celiac trunk made endovascular repair with the octopus endograft technique appear feasible...
April 2018: Journal of Endovascular Therapy
John J Cawley, Jürgen Kriwet
A new pycnodont fish from the early-mid Cenomanian, Late Cretaceous, of the 'Ein Yabrud quarry near the village of Beit Eil in Israel is the first pycnodont fish to be described from this locality. Due to the locality where it was found, Scalacurvithys naishi gen. et sp. nov. is considered an inhabitant of reefal waters interspersed with lagoons in the eastern Tethys Sea. Scalacurvichthys naishi is notable for its protruding, hook-shaped first dorsal ridge scale above a large triangular dermatocranium, a deeply sloped and antero-posteriorly shortened skull and bifurcated cloacal scales...
2018: Journal of Systematic Palaeontology
Tanja Stadler, Alexandra Gavryushkina, Rachel C M Warnock, Alexei J Drummond, Tracy A Heath
A birth-death-sampling model gives rise to phylogenetic trees with samples from the past and the present. Interpreting "birth" as branching speciation, "death" as extinction, and "sampling" as fossil preservation and recovery, this model - also referred to as the fossilized birth-death (FBD) model - gives rise to phylogenetic trees on extant and fossil samples. The model has been mathematically analyzed and successfully applied to a range of datasets on different taxonomic levels, such as penguins, plants, and insects...
March 14, 2018: Journal of Theoretical Biology
Gosse Overal, Bas Teusink, Frank J Bruggeman, Josephus Hulshof, Robert Planqué
Yeast glycolysis has been the focus of research for decades, yet a number of dynamical aspects of yeast glycolysis remain poorly understood at present. If nutrients are scarce, yeast will provide its catabolic and energetic needs with other pathways, but the enzymes catalysing upper glycolytic fluxes are still expressed. We conjecture that this overexpression facilitates the rapid transition to glycolysis in case of a sudden increase in nutrient concentration. However, if starved yeast is presented with abundant glucose, it can enter into an imbalanced state where glycolytic intermediates keep accumulating, leading to arrested growth and cell death...
March 14, 2018: Mathematical Biosciences
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