Antibandwidth of Complete k-ary Trees

AbstractThe antibandwidth problem is to label vertices of a n-vertex graph injectively by 1,2,3,…n, so that the minimum difference between labels of adjacent vertices is maximised. The problem is motivated by the obnoxious facility location problem, radiocolouring, work and game scheduling and is dual to the well known bandwidth problem. We prove exact results for the antibandwidth of complete k-ary trees, k even, and estimate the parameter for odd k up to the second order term. This extends previous results for complete binary trees

Present Constraints on the H-dibaryon at the Physical Point from Lattice QCD

The current constraints from lattice QCD on the existence of the H-dibaryon are discussed. With only two significant lattice QCD calculations of the H-dibaryon binding energy at approximately the same lattice spacing, the forms of the chiral and continuum extrapolations to the physical point are not determined. In this brief report, we consider the constraints on the H-dibaryon imposed by two simple chiral extrapolations. In both instances, the extrapolation to the physical pion mass allows for a bound H-dibaryon or a near-threshold scattering state. Further lattice QCD calculations are required to clarify this situation.Comment: 8 pages, 2 figures, 1 table; revised for the journa

Long-term cerebral thromboembolic complications of transapical endocardial resynchronization therapy

Purpose: Cardiac resynchronization therapy (CRT) is an established therapeutic option in selected heart failure patients (pts). However, the transvenous left ventricular (LV) lead implantation remains ineffectual in a considerable number of pts. Transapical LV (TALV) lead implantation is an alternative minimally invasive, surgical, endocardial implantation technique. The aim of the present prospective study is to determine the long-term outcome, including the cerebral thromboembolic complications, of pts

Эффективность СРАР или высокочастотной Jet-вентиляции с помощью назо-оральной маски в лечении отека легких

Objective: to compare the efficiency of continuous positive airway pressure (CPAP) and high-frequency jet ventilation by means of a mask (HFJV-M) in the treatment of cardiogenic edema of the lung. Design: a retrospective study. Setting: Department of Anesthesiology and Intensive Medicine, Hospital NsP, Vranov, Slovakia. Subjects and methods. A hundred and ninety-six patients with varying cardiogenic edema of the lung were divided into 3 groups according to the severity of pulmonary edema (PE). By taking into account comparable pharmacotherapy, mean airway pressure, and FiO2, the authors compared the efficiency of CPAP (n=64) and HFJV-M (n=101) from the rate of changes in respiration rate, blood oxygenation, acid-base balance, and the duration of ventilation support and the length of stay in the intensive care unit (ICU). The results were assessed by the unpaired Student’s test. The procedure of artificial ventilation via HFJV-M was approved by the Professional and Ethics Committee, Ministry of Health in the Republic of Slovakia, in 1989 for clinical application. Results. Comparison of CPAP or HFJV-M used in mild PE that was called Phase 1 of PE revealed no statistically significant differences in the parameters being assessed. In severer forms of PE characterized as Phases 2 and 3, the use of HFJV-M in the first 3 hours of ventilation maintenance caused a rapider reduction in spontaneous respiration rate from 25—33 per min to 18—22 per min (p>0.01). The application of HFJV-M also showed a statistically significant difference in the correction rate of PaO2, pH, and oxygenation index (PaO2/FIO2) (p>0.01) predominantly within the first 2 hours of therapy. Comparison of the mean duration of necessary ventilation maintenance (CPAP versus HFJV-M: 10.9 versus 6.8 hours) and the mean length of stay in the ICU (CPAP versus HFJV-N: 2.7 versus 2 days) revealed a statistically significant difference (p>0.01 and p>0.05, respectively). Only 6.6% of the HFJV-M group patients needed intubation and routine ventilation modes. Conclusion. The statistical analysis of controlled parameters (oxygenation, acid-base balance, duration of ventilation maintenance, length of hospital stay, and intubation needs) established that ventilation maintenance by HFJV-M versus CPAP was more effective just in the first 2—5 hours of therapy. When HFJV-M was used, the duration of required ventilation maintenance and the length of stay in the ICU were less since the need for intubation decreased to 6.6%.Цель исследования — сравнение эффективности режимов вентиляции с постоянным положительным давлением (CPAP) и высокочастотной струйной вентиляции с помощью маски (HFJV-M) в лечении кардиогенного отека легких. Тип исследования — ретроспективное. Имя и адрес места исследования: Отделение анестезиологии и интенсивной помощи (АРО), госпиталь NsP Vranov, Словакия. Материал и методы. 196 больных с различной формой кардиогенного отека легких (ОЛ) были разделены на 3 группы, согласно тяжести ОЛ. При сопоставимой фармакотерапии, среднем давлении в дыхательных путях и FiO2, авторы сравнили эффективность CPAP (у 64 пациентов) и HFJV-M (у 101 пациента) по скорости изменений частоты дыхания, оксигенации крови, КОС, а также продолжительности вентиляционной поддержки и госпитализации в АРО. Результаты оценивали с помощью непарного теста Стьюдента. Методика ИВЛ (искусственной вентиляции легких) посредством HFJV-M была одобрена для клинического использования профессиональным и этическим комитетом министерства здоровья в республике Словакия в 1989 году. Результаты. Сравнение использования CPAP или HFJV-M при легкой форме ОЛ, которая названа 1-й фазой ОЛ, не выявило статистически значимых различий оцениваемых параметров. При более тяжелых формах ОЛ, охарактеризованных как 2-я и 3-я фазы ОЛ, применение HFJV-M в первые 3 часа вентиляционной поддержки привело к более быстрому снижению частоты самостоятельного дыхания с 25—33 в минуту до 18—22 в минуту (р>0,01). При использовании HFJV-M обнаружили также статистически значимую разницу в скорости коррекции PaO2, pH и индекса оксигенации (PaO2/FIO2) (р>0,01), преимущественно в первые 2 часа терапии. При сравнении средней длительности необходимой вентиляционной поддержки (CPAP против HFJV-M: 10,9 против 6,8 часов) и средней длительности госпитализации (CPAP против HFJV-M: 2,7 против 2 дней) выявили статистически значимую разницу (р>0,01 и р>0,05, соответственно). Необходимость в интубации и использовании обычных методов вентиляции возникла только у 6,6% больных, включенных в исследование эффективности HFJV-M. Заключение. После статистического анализа контролируемых параметров (оксигенация, КОС, длительность вентиляционной поддержки, длительность госпитализации, необходимость интубации) было установлено, что вентиляционная поддержка с помощью HFJV-M в сопоставлении с CPAP более эффективна уже в первые 2—5 часов терапии. При применении HFJV-M продолжительность необходимой вентиляционной поддержки и госпитализации в ОРИТ меньше, поскольку необходимость интубации снизилась до 6,6%

Limited Tumor Tissue Drug Penetration Contributes to Primary Resistance against Angiogenesis Inhibitors

Resistance mechanisms against antiangiogenic drugs are unclear. Here, we correlated the antitumor and antivascular properties of five different antiangiogenic receptor tyrosine kinase inhibitors (RTKIs) (motesanib, pazopanib, sorafenib, sunitinib, vatalanib) with their intratumoral distribution data obtained by matrix-assisted laser desorption ionization mass spectrometry imaging (MALDI-MSI). In the first mouse model, only sunitinib exhibited broad-spectrum antivascular and antitumor activities by simultaneously suppressing vascular endothelial growth factor receptor-2 (VEGFR2) and desmin expression, and by increasing intratumoral hypoxia and inhibiting both tumor growth and vascularisation significantly. Importantly, the highest and most homogeneous intratumoral drug concentrations have been found in sunitinib-treated animals. In another animal model, where - in contrast to the first model - vatalanib was detectable at homogeneously high intratumoral concentrations, the drug significantly reduced tumor growth and angiogenesis. In conclusion, the tumor tissue penetration and thus the antiangiogenic and antitumor potential of antiangiogenic RTKIs vary among the tumor models and our study demonstrates the potential of MALDI-MSI to predict the efficacy of unlabelled small molecule antiangiogenic drugs in malignant tissue. Our approach is thus a major technical and preclinical advance demonstrating that primary resistance to angiogenesis inhibitors involves limited tumor tissue drug penetration. We also conclude that MALDI-MSI may significantly contribute to the improvement of antivascular cancer therapies

Intracardiac echocardiography to guide transseptal catheterization for radiofrequency catheter ablation of left-sided accessory pathways: two case reports

Intracardiac echocardiography (ICE) is a useful tool for guiding transseptal puncture during electrophysiological mapping and ablation procedures. Left-sided accessory pathways (LSAP) can be ablated by using two different modalities: retrograde approach through the aortic valve and transseptal approach with puncture of the fossa ovalis. We shall report two cases of LSAP where transcatheter radiofrequency ablation (TCRFA) was firstly attempted via transaortic approach with ineffective results. Subsequently, a transseptal approach under ICE guidance has been performed. During atrial septal puncture ICE was able to locate the needle tip position precisely and provided a clear visualization of the "tenting effect" on the fossa ovalis. ICE allowed a better mapping of the mitral ring and a more effective catheter ablation manipulation and tip contact which resulted in a persistent and complete ablation of the accessory pathway with a shorter time of fluoroscopic exposure. ICE-guided transseptal approach might be a promising modality for TCRFA of LSAP

Matrix metalloproteinase-9 activity and a downregulated Hedgehog pathway impair blood-brain barrier function in an <i>in vitro</i> model of CNS tuberculosis

Central nervous system tuberculosis (CNS TB) has a high mortality and morbidity associated with severe inflammation. The blood-brain barrier (BBB) protects the brain from inflammation but the mechanisms causing BBB damage in CNS TB are uncharacterized. We demonstrate that Mycobacterium tuberculosis (Mtb) causes breakdown of type IV collagen and decreases tight junction protein (TJP) expression in a co-culture model of the BBB. This increases permeability, surface expression of endothelial adhesion molecules and leukocyte transmigration. TJP breakdown was driven by Mtb-dependent secretion of matrix metalloproteinase (MMP)-9. TJP expression is regulated by Sonic hedgehog (Shh) through transcription factor Gli-1. In our model, the hedgehog pathway was downregulated by Mtb-stimulation, but Shh levels in astrocytes were unchanged. However, Scube2, a glycoprotein regulating astrocyte Shh release was decreased, inhibiting Shh delivery to brain endothelial cells. Activation of the hedgehog pathway by addition of a Smoothened agonist or by addition of exogenous Shh, or neutralizing MMP-9 activity, decreased permeability and increased TJP expression in the Mtb-stimulated BBB co-cultures. In summary, the BBB is disrupted by downregulation of the Shh pathway and breakdown of TJPs, secondary to increased MMP-9 activity which suggests that these pathways are potential novel targets for host directed therapy in CNS TB