Journal articles: 'C++ Qt'

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Garoufalidis, Stavros, and Christian Zickert. "The symplectic properties of the PGL($n,\mathbb C$)-gluing equations." Quantum Topology 7, no. 3 (2016): 505–51. http://dx.doi.org/10.4171/qt/80.

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DI NARDO, ROSARIA, FILOMENA FEO, and OLIVIER GUIBÉ. "EXISTENCE RESULT FOR NONLINEAR PARABOLIC EQUATIONS WITH LOWER ORDER TERMS." Analysis and Applications 09, no. 02 (April 2011): 161–86. http://dx.doi.org/10.1142/s0219530511001790.

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In this paper, we prove, the existence of a renormalized solution for a class of nonlinear parabolic problems whose prototype is [Formula: see text] where QT = Ω × (0, T), Ω is an open and bounded subset of ℝN, N ≥ 2, T > 0, Δp is the so called p-Laplace operator, [Formula: see text], c ∈ (Lr(QT))N with [Formula: see text], [Formula: see text], b ∈ LN+2, 1(QT), f ∈ L1(QT), g ∈ (Lp'(QT))N and u0 ∈ L1(Ω).

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Sredniawa, B., A. Musialik-Lydka, P. Jarski, Z. Kalarus, and L. Polonski. "P-062 Sex differences of corrected QT interval and QT dynamics and torsade de pointes." EP Europace 4, Supplement_2 (December 1, 2003): B81. http://dx.doi.org/10.1016/eupace/4.supplement_2.b81-c.

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Chang, Kai-Ting, Hsu-Shien Shu, Chun-Yuan Chu, Wen-Hsien Lee, Po-Chao Hsu, Ho-Ming Su, Tsung-Hsien Lin, Wen-Chol Voon, Wen-Ter Lai, and Sheng-Hsiung Sheu. "Association between C-reactive protein, corrected QT interval and presence of QT prolongation in hypertensive patients." Kaohsiung Journal of Medical Sciences 30, no. 6 (June 2014): 310–15. http://dx.doi.org/10.1016/j.kjms.2014.02.012.

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Strevel, Elizabeth L., Douglas J. Ing, and Lillian L. Siu. "Molecularly Targeted Oncology Therapeutics and Prolongation of the QT Interval." Journal of Clinical Oncology 25, no. 22 (August 1, 2007): 3362–71. http://dx.doi.org/10.1200/jco.2006.09.6925.

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Investigation and utilization of molecularly targeted agents has induced a number of drug adverse effects that are not typically associated with conventional chemotherapy. QT interval prolongation, a cardiac toxicity that increases the risk of fatal arrhythmia, is associated with several novel oncology therapies. Classes of molecularly targeted agents with described QT effects include histone deacetylase inhibitors, multitargeted tyrosine kinase inhibitors, vascular disruption agents, farnesyl protein transferase inhibitors, Src/Abl kinase inhibitors, and protein kinase C inhibitors. Concurrently, guidelines for monitoring the QT-prolonging effects of drugs under development have become increasingly rigorous. Although these guidelines apply to anticancer agents, they were not specifically designed for the oncology patient population. This article will review the pathophysiology of QT prolongation, methods of preclinical QT assessment, and current guidelines for QT evaluation in early phase trials. Additionally, molecularly targeted agents with QT effects will be summarized, and mechanisms of addressing this toxicity in the context of oncology drug development will be explored.

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Viscido, Angelo, Annalisa Capannolo, Renata Petroni, Gianpiero Stefanelli, Giulia Zerboni, Massimo De Martinis, Stefano Necozione, et al. "Association between Corrected QT Interval and C-Reactive Protein in Patients with Inflammatory Bowel Diseases." Medicina 56, no. 8 (July 30, 2020): 382. http://dx.doi.org/10.3390/medicina56080382.

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Background and objectives: Electrocardiograph abnormalities (i.e., QT interval prolongation) have been described in inflammatory bowel diseases (IBD). We aimed to measure the QT interval in a cohort of patients with IBD and to analyze its relationship with clinical and inflammatory activity. Materials and Methods: We performed a cross-sectional study that included 38 IBD outpatients and 38 “age- and sex-matched” healthy controls. Nine patients had active IBD, and 29 were in clinical remission. Among the latter, 10 patients had sustained (lasting >1 year) and 19 had short-term remission (≤1 year). Corrected QT (QTc) interval was measured on standard 12-lead electrocardiograph. A systematic review of the literature on studies investigating the QT interval in patients with IBD was also performed. Results: QTc interval values were similar between IBD patients and healthy controls (417.58 ± 22.05 ms vs. 409.13 ± 19.61 ms, respectively; p: 0.479). Patients with active IBD had significantly higher QTc values (435.11 ± 27.31 ms) than both controls (409.13 ± 19.61 ms) and patients in remission (412.14 ± 17.33 ms) (p: 0.031). Post hoc analysis showed that the difference in QTc values between active IBD and remission was attributable to the group of patients with sustained remission (p < 0.05). Lastly, a significant correlation between QTc interval and C-reactive protein (CRP) values was observed (Spearman test: r = 0.563; p: 0.0005). Conclusions: Our study demonstrates an association between QTc duration and both clinical and inflammatory activity in patients with IBD. The higher the CRP value, the longer is the QTc duration. For practical purposes, all patients with active IBD should undergo a standard ECG. Prescription of drugs able to modify the QT interval should be avoided in patients with active IBD. The systematic review of the literature indicated that this is the first published study demonstrating an association between the QTc duration and CRP values in patients with IBD.

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Zhou, Hui, Wei Lai, Wengen Zhu, Jinyan Xie, Xin Liu, Yang Shen, Ping Yuan, et al. "Genotype-based clinical manifestation and treatment of Chinese long QT syndrome patients with KCNQ1 mutations – R380S and W305L." Cardiology in the Young 26, no. 4 (September 7, 2015): 754–63. http://dx.doi.org/10.1017/s1047951115001304.

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AbstractAimMost long QT syndrome patients are associated with genetic mutations. We aimed to investigate the clinical and biochemical characteristics and look for genotype-based preventive implications in Chinese long QT syndrome patients.Methods and resultsWe identified two missense mutations of the KCNQ1 gene in two independent Chinese families, including a previously reported mutation R380S in the C-terminus and a novel mutation W305L in the P-loop domain of the Kv7.1 channel, respectively. The proband with R380S was an 11-year-old girl who suffered a prolonged corrected QT interval of 660 ms, recurrent syncope, and sudden cardiac death, whose father was an asymptomatic carrier. The mutation W305L was detected in a 36-year-old woman with long QT syndrome and her immediate family members including the proband’s younger sister with an unexplained syncope, her son, and her elder daughter without symptoms. Metoprolol appeared to be effective in preventing arrhythmias and syncope in long QT syndrome patients with mutation W305L. Both R380S and W305L mutations led to “loss-of-function” of the Kv7.1 channel accounting for the clinical phenotypes.ConclusionsWe first show two missense KCNQ1 mutations – R380S and W305L – in Chinese long QT syndrome patients, resulting in the loss of protein function. Mutation W305L in the P-loop domain of the Kv7.1 may derive a pronounced benefit from β-blocker therapy in symptomatic long QT syndrome patients, whereas mutation R380S located in the C-terminus may be associated with a high risk of sudden cardiac death.

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Pasternak, Y., N. Shechter, R. Loebstein, N. Markovits, I. Gueta, H. Halkin, and H. Yarden‐Bilavsky. "Voriconazole‐induced QT c prolongation in a paediatric population." Acta Paediatrica 108, no. 6 (December 14, 2018): 1128–32. http://dx.doi.org/10.1111/apa.14652.

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Chen, Nianhang, Ying Ye, Liangang Liu, Josephine Reyes, Mahmoud S. Assaf, Claudia Kasserra, Simon Zhou, and Maria Palmisano. "Lenalidomide at Therapeutic and Supratherapeutic Doses Does Not Prolong QT c Intervals in the Thorough QT c Study Conducted in Healthy Men." Basic & Clinical Pharmacology & Toxicology 113, no. 3 (June 20, 2013): 179–86. http://dx.doi.org/10.1111/bcpt.12081.

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Asfaw, Meseret, Davd Lee Holtzman, Gene F. Kwan, lawrence T. Oyewusi, carole D. Mitnick, and Kwanjune J. Seung. "N C I D E N C E O F H I G H G R A D E Q T C F P R O L O N G A T I O N A N D I T S M A N A G E M E N T A M O N G P A T I E N T S U N D E R G O I N G T R E A T M E N T F O R D R U G R E S I S T A N T T U B E R C U L O S I S ( D R - T B ) : C A S E S E R I E S ." African Journal of Infectious Diseases 15, no. 2s (September 1, 2021): 38–41. http://dx.doi.org/10.21010/ajid.v15i2s.5.

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Background: The World Health Organization (WHO) has approved the use of two new drugs, namely Bedaquiline (Bdq) and Delamanid (Dlm), for treatment of Drug Resistant Tuberculosis (DR-TB). One of the concerns raised with the use of these drugs was QT-interval prolongation. This condition could be serious and life threatening. Hence, knowing the magnitude and its management is very important. This case series identifies the incidence and discusses the management of clinically significant QT-interval prolongation amongst a cohort of patients who have been on these medicines. Materials and Methods: Patients with reports of high grade QT-Interval prolongation (i.e. Grade-3 and Grade-4) were identified from the cohort of 265 patients enrolled on bedaquiline and/or delamanid and discussion is made on the pattern, severity and management of each cases identified. Results: Only 4 (1.5%) out of all 265 patients enrolled on Bedaquiline and/or Delamanid have developed high grade QT-Interval prolongation. And all are managed without permanent discontinuation of both drugs. Conclusion: The Incidence of clinically significant QTcF-interval prolongation among DR-TB patients taking bedaquiline and /or delamanid in Lesotho is low. And almost all cases can be managed with more frequent Electrocardiogram (ECG) monitoring and management of other possible causes of QT-interval prolongation without the need to stop one or both drugs permanently.

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INGOLD, MARIKO, SASKIA SCHMIDT, HERBERT DIETZ, RAINER GEORG JOERGENSEN, EVA SCHLECHT, and ANDREAS BUERKERT. "TANNINS IN GOAT DIETS MODIFY MANURE TURNOVER IN A SUBTROPICAL SOIL." Experimental Agriculture 54, no. 5 (July 24, 2017): 655–69. http://dx.doi.org/10.1017/s0014479717000291.

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SUMMARYQuality of animal manure as a nutrient source for crops and as a soil conditioner depends on how fast the organic matter is decomposed, releasing plant nutrients or building up the soil organic matter (SOM) pool. This turnover process is governed by manure composition, soil temperature, soil moisture and secondary metabolites in the manure such as tannins. To investigate the turnover and nutrient release from tannin-containing manure, a litterbag experiment was conducted in an irrigated lowland soil of northern Oman. A standardized quebracho tannin extract (QT) was either added to the goats’ diet and defecated with manure (QTf), or added to manure in a QT water suspension (QTc) prior to field application. Litterbags were installed within a two-year field experiment at 10-cm depth at the beginning of a consecutive sweet corn and radish cultivation, followed by their recovery every 2-–6 weeks until crop harvests. The litterbags contained pure goat manure (control) and the two types of QT-amended goat manure. Generally, QT increased OM remaining in litterbags at sampling by up to 22% compared with the control. QT reduced relative C, N, P and K release by 10% to 63% compared with the control, but effects were contradictory under sweet corn and radish. While under radish, both QT treatments reduced or tended to reduce C, N, P and K release from manure, QTc even increased N and P release under sweet corn. QTf, on the other hand, did not affect C, P and K release under sweet corn, whereas N release was reduced by 36–63% under both crops. As quebracho tannins in goat manure slowed down organic matter decomposition and reduced nutrient release, they may be useful agents in manure application to increase SOM pools and soil nutrient pools. However, the immobilization particularly of N by tannins can reduce the availability of this nutrient to crops.

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Aoued, Samy, Frédéric Danoix, Sébastien Y. P. Allain, Steve Gaudez, Guillaume Geandier, Jean-Christophe Hell, Michel Soler, and Mohamed Gouné. "Microstructure Evolution and Competitive Reactions during Quenching and Partitioning of a Model Fe–C–Mn–Si Alloy." Metals 10, no. 1 (January 16, 2020): 137. http://dx.doi.org/10.3390/met10010137.

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The mechanisms behind the carbon enrichment of austenite during quenching and partitioning are still a matter of debate. This work investigates the microstructural evolution during the quenching and partitioning of a model Fe–C–Mn–Si alloy by means of in situ high energy X-ray diffraction (HEXRD) atom probe tomography, and image analysis. The ultra-fast time-resolved quantitative information about phase transformations coupled with image analysis highlights the formation of carbide-free BCT bainite, which is formed within a very short range during the reheating and partitioning step. Its transformation rate, which is a better indicator than the intrinsic volume fraction, depends on the quenching temperature (QT). It is shown to decrease with decreasing QT, from 45% at QT = 260 °C to 20% at QT = 200 °C. As a consequence, a significant part of the carbon enrichment observed in austenite can be attributed to bainite transformation. Furthermore, a large part of carbon was shown to be trapped into martensite. Both the formation of Fe2.6C iron carbides and the segregation of carbon on lath boundaries in martensite were highlighted by atom probe tomography. The energy for carbon segregation was determined to be 0.20 eV, and the carbon concentration on the lath boundaries was obtained to be around 25 at %. Therefore, the carbon enrichment of austenite is the result of competitive reactions such as carbon partitioning from martensite, bainite transformation, and carbon trapping in martensite.

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Calborean, Veronica, Victor Gheorman, Octavian Istratoaie, Roxana Edme Mustafa, Petre Alexandru Cojocaru, Dragos Ovidiu Alexandru, Oana Galceava, et al. "QT Interval Analysis in Patients with Chronic Liver Disease." Revista de Chimie 69, no. 5 (June 15, 2018): 1134–38. http://dx.doi.org/10.37358/rc.18.5.6275.

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The prevalance of QT prolongation in chronic viral liver disease is high and the risk of complications is increased. We wanted to study the QT interval prolongation at the patients diagnosed with chronic hepatic disease and also to evaluate some of clinical and biochemical variables. We studied a cohort with 126 patients diagnosed with chronic viral hepatic diseases hospitalised to Cardiology Department, to the County Hospital of Craiova, between Octomber 2016 and January 2018. We aimed to determine the occurrence of QT interval prolongation in a large series of patients with chronic hepatic disease of viral etiology. We wanted to evaluated the QT prolongation to clinical and biochemical variables. The QT interval was measured by a standard 12-lead ECG for each patient, with prolongation defined as 460 ms. Multiple clinical and biochemical variables were evaluated including sex, age, areas (rural/urban) the frequency of arrhythmic events (PACs, PVCs, Atrial fibrillation, Bradycardia, Tachycardia), NT proBNP, Hb,uric acid, creatinine, alanine aminotransferase (ALT), aspartate aminotransferase (AST) , cholesterol, triglyceride, etc. The group of patients was composed by 43 woman and 83 men. From 43 women, representing 65.06% (461.56 �42.03) and from 83 men, means 66.67% (461.14 � 45.10) presented interval QT prolongation. Studing the distribution of hepatic etiologies we can see that 34 patients had hepatitis B, 35 patients hepatitis C, 5 patients B and C dual virus infection and 52 patients with chronic liver disease of etiology other than viral. We registered close results about QT interval prolongation on group, sex and origine group of patients. The value of QT interval to our patients was higher compared to other values recorder in other studies, at the patients with chronic hepatic disease, despide the fact we chose a higher value of QT prolongation. The highest value of QT interval was in the group of age between 60 and 69, even if in other studies we notice a prolonged QT interval at patients over 70 years old. The biological and biochemical profile of chronic hepatic disease of the subjects included in our study showed no statistical difference between male and female patients.We found a higher incidence of arrhythmic events, at patients with chronic hepatic disease of viral etiology, especially to premature atrial contraction and atrial fibrillation.We found a couple of correlation between QT interval prolongation and the evolution of chronic hepatic disease of viral etiology. It is very important to develop a strong and complex strategies to prevent and to treat the arrhythmic event presented at the patients diagnosticated with hepatic disease, because of the higher risk of developing life-threatening arrhythmias, includen sudden cardiac death.

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Pasikova, Tetiana, and Elżbieta Miłosz. "Analiza porównawcza narzędzi RAD do wizualnego programowania w języku C++." Journal of Computer Sciences Institute 2 (December 30, 2016): 76–80. http://dx.doi.org/10.35784/jcsi.115.

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W artykule przedstawiono porównanie wybranych narzędzi RAD do wizualnego programowania w języku C++. Do porównania zostały wybrane środowiska programistyczne: C++ Builder, Visual Studio, Qt Creator. Wielokryterialna analiza porównawcza i wybór najlepszego środowiska do nauki wizualnego programowania w C++ zostały przeprowadzone na podstawie danych producenta i przeprowadzonego eksperymentu ze studentami.

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LEHNINGER, HARALD, and YUNKANG LIU. "The functional-differential equation y′(t)=Ay(t) +By(qt) +Cy′(qt) +f(t)." European Journal of Applied Mathematics 9, no. 1 (February 1998): 81–91. http://dx.doi.org/10.1017/s0956792597003343.

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An initial value problem for the functional differential equationy′(t) =Ay(t) +By(qt) +Cy′(qt) +f(t), t ≥ t0 > 0where A, B, C are complex matrices, q∈(0, 1), and f is a vector of continuous functions, is considered in this paper. Its solution is represented in terms of the fundamental solution via the variation-of-constants formula. For some special cases, the fundamental solutions are formulated as piecewise Dirichlet series. The variation-of-constants formula is used to analysis the asymptotic behaviour of the solutions of some scalar equations, including one with variable coefficients related to coherent states of the q-oscillator algebra in quantum mechanics.

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Su, Hang, Xi Qing Zhao, Tao Pan, Xiao Rong Lei, and Qing Feng Wang. "Microstructure and Mechanical Properties in QT-Treated 9Ni Steel." Advanced Materials Research 562-564 (August 2012): 39–42. http://dx.doi.org/10.4028/www.scientific.net/amr.562-564.39.

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Microstructure and mechanical properties in QT-Treated 9Ni steel were investigated. The detail microstructures were observed by optical microscope (OM) and transmission electron microscope (TEM). The volume fraction of austenite was estimated by XRD. Tensile test at room temperature and Charpy-V-Notch (CVN) impact test at -196°C were carried out. The results showed that the microstructure of QT-treated 9%Ni steel was composed of tempered martensite and reversed austenite. The brittle cementite was absorbed gradually by the increasing reversed austenite as the tempering temperature increased. The optimum tempering temperature range was 560°C~580°C. The reversed austenite could improve the cryogenic toughness of 9Ni steel through the combination of the scavenging effect and the TRIP effect.

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Waddell-Smith, Kathryn E., Nikki Earle, and Jonathan R. Skinner. "Must every child with long QT syndrome take a beta blocker?" Archives of Disease in Childhood 100, no. 3 (September 30, 2014): 279–82. http://dx.doi.org/10.1136/archdischild-2014-306864.

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Long QT syndrome is the most commonly recognised cause of sudden cardiac death in children. With a prevalence of 1 in 2000, family screening is identifying large numbers of hitherto asymptomatic gene carriers in the community, about a third of whom have a normal QT interval. The mainstay of treatment is long term uninterrupted beta blocker therapy, a treatment with many potential side effects. This article reviews the evidence and suggests a cohort who may, after assessment in a specialised cardiac-genetic clinic, be spared this treatment because of very low baseline risk. These are asymptomatic boys and prepubertal girls with a heart rate corrected QT interval persistently less than 470 ms who do not indulge in high risk activities (especially swimming) and do not have a missense mutation in the c-loop region of the KCNQ1 (long QT 1) gene.

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Oliveira, Filipe. "Approximation of the DNLS equation by the cubic nonlinear Schrödinger equation." Proceedings of the Royal Society of Edinburgh: Section A Mathematics 134, no. 3 (June 2004): 595–607. http://dx.doi.org/10.1017/s030821050000336x.

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We rigorously approach the Schrödinger equation of derivative type qt + iqxx + λ |q|2qx + μq2q̄x = 0, λ ∈ R, μ ∈ C, by the cubic nonlinear Schrödinger equation AT + i AXX + i k0 (λ − μ) |A|2A = 0. We also study the case of the KdV-like equation qt + i qxx + aqxxx + i |q|2q + λ̃ (|q|2q)x + μ̃ |q|2qx = 0, λ̃ μ̃ ∈ R, arising in optical physics.

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Hincapie-Castillo, Juan M., Benjamin Staley, Carl Henriksen, Arwa Saidi, Gloria Pflugfelder Lipori, and Almut G. Winterstein. "Development of a predictive model for drug-associated QT prolongation in the inpatient setting using electronic health record data." American Journal of Health-System Pharmacy 76, no. 14 (June 11, 2019): 1059–70. http://dx.doi.org/10.1093/ajhp/zxz100.

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Abstract Purpose We aimed to construct a dynamic model for predicting severe QT interval prolongation in hospitalized patients using inpatient electronic health record (EHR) data. Methods A retrospective cohort consisting of all adults admitted to 2 large hospitals from January 2012 through October 2013 was established. Thirty-five risk factors for severe QT prolongation (defined as a Bazett’s formula—corrected QT interval [QTc] of ≥500 msec or a QTc increase of ≥60 msec from baseline) were operationalized for automated EHR retrieval; upon univariate analyses, 26 factors were retained in models for predicting the 24-hour risk of QT events on hospital day 1 (the Day 1 model) and on hospital days 2–5 (the Days 2–5 model). Results A total of 1,672 QT prolongation events occurred over 165,847 days of risk exposure during the study period. C statistics were 0.828 for the Day 1 model and 0.813 for the Days 2–5 model. Patients in the upper 50th percentile of calculated risk scores experienced 755 of 799 QT events (94%) allocated in the Day 1 model and 804 of 873 QT events (92%) allocated in the Days 2–5 model. Among patients in the 90th percentile, the Day 1 and Days 2–5 models captured 351 of 799 (44%) and 362 of 873 (41%) QT events, respectively. Conclusion The risk models derived from EHR data for all admitted patients had good predictive validity. All risk factors were operationalized from discrete EHR fields to allow full automation for real-time identification of high-risk patients. Further research to test the models in other health systems and evaluate their effectiveness on outcomes and patient care in clinical practice is recommended.

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Drew, D., A. Baranchuk, and R. J. Brison. "P037: The impact of fever on corrected QT interval in a general emergency department population." CJEM 18, S1 (May 2016): S90—S91. http://dx.doi.org/10.1017/cem.2016.213.

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Introduction: Fever is one of the most common reasons for presentation to the emergency department (ED). Interestingly, a number of small studies suggest that fever may function as a modulator of the QT interval in healthy individuals and an arrhythmogenic trigger in patients with occult congenital QT abnormalities. The objective of this study was to explore whether presence of fever adversely affects the QT interval, and whether medications known to prolong this interval affect any association found. Methods: We performed a retrospective, single center study identifying patients (age > 18 years) presenting to the ED with fever (temperature > 38.0 °C) between January 1st, 2012 and December 31st, 2013 via electronic chart review. The subset for analysis were those who had an ECG both at time of fever and while afebrile (within 30 days of initial ECG). Temperature measurement was within 30 minutes of ECG. Actively paced patients were excluded. Univariate and multiple regression analysis were used to determine risk factors for QT derangement in patients with fever. Results: 2018 febrile visits occurred during the reviewed period, 181 of these patients went on to be included in the study. 54.1% of study subjects were female, and the average age was 68.9 years old. The etiology of fever was predominately infectious (69.6%), with community acquired pneumonia being the most frequent cause (24.3%). We found the median corrected QT interval to be significantly shorter in febrile as compared to afebrile patients [QTc = 388.7ms, (371.5-407.5) vs 406.7, (386.7-434.4); p < 0.001]. This difference was observed in both sexes. Males were found to be more likely to experience medication induced QTc prolongation [OR 5.35, 95% CI = 1.46 - 19.68; P < 0.05]. Two instances of Torsades de pointes were identified in our study, both occurring in males on QT prolonging medications. Conclusion: In an ED patient population, fever generally shortens the QT interval independent of sex. Prolongation of the QT interval during fever should thus increase clinical suspicion of congenital or acquired QT disorders. Additionally, males appear to be more susceptible to medication-induced derangements in the QT interval and may require more vigilant monitoring when treated with multiple QT prolonging medications.

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Akkuş, Oğuz, Gamze Akkuş, and Onur Kaypaklı. "The Possible Effects of Dapagliflozin on 12-derived Electrocardiogram in Patients with Type 2 Diabetes Mellitus." Endocrine, Metabolic & Immune Disorders - Drug Targets 19, no. 2 (February 7, 2019): 207–13. http://dx.doi.org/10.2174/1871530319666181218121508.

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Background: Dapagliflozin, sodium glucose cotransporter 2 inhibitor, has potential side effects on electrolyte imbalance as it has diuretic effects which include decreasing glucose reabsorption, increasing glucosuria and natriuresis. We aimed to determine the possible effects of dapagliflozin on electrocardiogram (ECG) in patients with type 2 DM. </P><P> Material and Methods: This retrospective study consisted of 49 patients (25 female, 24 male). Patients who had inadequate glycemic control besides using several oral antidiabetics, subsequently endorsed with dapagliflozin, were included in the current study. Results: Meantime interval from treatment initiation to control was 10.5 ± 5.03 weeks. Body mass index, glucose, HbA1C, eGFR, LDL-C, heart rate, systolic and diastolic blood pressures were found to be significantly lower at control admission (p<0.05). Creatinine and QT interval were significantly higher at control admission (p<0.05). Baseline Tpe duration and baseline Tpe/QT ratio were found to be significantly correlated with Tpe/QT difference (p<0.05). In linear regression analysis, baseline Tpe/QT ratio was found to be the sole independent predictor of Tpe/QT difference (p<0.05). Conclusion: Initiation of dapagliflozin treatment seems to be safe, up to several months, in terms of serum electrolytes and ECG findings in patients with type 2 DM with a probable improvement.

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Njock Bayock, Francois, Paul Kah, Pavel Layus, and Victor Karkhin. "Numerical and Experimental Investigation of the Heat Input Effect on the Mechanical Properties and Microstructure of Dissimilar Weld Joints of 690-MPa QT and TMCP Steel." Metals 9, no. 3 (March 20, 2019): 355. http://dx.doi.org/10.3390/met9030355.

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The study evaluates numerically and experimentally the effect of welding heat input parameters on the microstructure and hardness of the heat-affected zone (HAZ) of quenched and tempered (QT) and thermo-mechanically controlled process (TMCP) 690-MPa high-strength steel. Numerical analyses and experimental comparisons were applied using three heat input values (10, 14, and 17 kJ/cm) in order to predict the thermal fields during welding. Experimental analysis was carried out of the microstructure and microhardness behavior in different HAZ areas. The numerical values indicate that the maximum respective values of temperature measured in QT steel and TMCP steel were about 1300 and 1200 °C for a heat input of 10 kJ/cm, 1400 and 1300 °C for a heat input of 14 kJ/cm, and 1600 and 1450 °C for a heat input of 17 kJ/cm. The cooling times resulted, for a heat input of 10 kJ/cm, in numerical t8/5 (14.5 s) and experimental (18.84 s) increases in hardness in the coarse-grain heat-affected zone (CGHAZ) of the QT steel (317 HV0.1), due to the formation of bainite and lath martensite structures with grain growth. Decreased hardness in the CGHAZ of TMCP steel (240 HV0.1) was caused by primary recrystallization of the microstructure and the formation of more equilibrium products of austenite decomposition. Increasing the heat input (14 to 17 kJ/cm) led to numerical t8/5 (29 s) and experimental (36 s) decreases in hardness in the CGHAZ of QT steel (270 HV0.1) due to the full austenite (thermal weld cycle), and maintained the relative value of TMCP steel (235 HV0.1).

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Kitamura, Michihide, and Akinobu Irie. "Spin Flows in Magnetic Semiconductor/Insulator/Superconductor Tunneling Junction." International Journal of Superconductivity 2015 (April 5, 2015): 1–9. http://dx.doi.org/10.1155/2015/273570.

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Tunneling currents along the c-axis of the majority and minority spin electrons have been studied for a magnetic semiconductor (MS)/insulator (I)/superconductor (S) tunneling junction consisting of a Ga1−xMnxAs MS with x = 1/32, a nonmagnetic I with a realistic dimension, and a HgBa2Ca2Cu3O8.4 (Hg-1223) high-Tc S. The normalized charge and spin currents, QT,Cμ′Vex and QT,Sμ′Vex, and the flows of the majority ↑ and minority ↓ spin electrons, QT,↑μ′Vex and QT,↓μ′Vex, have been calculated at a fixed external voltage Vex, as a function of the magnetic moment μ′ (≡μ/μB) per a Mn atom which is deduced from the band structure calculations. It is found that the tunneling due to the minority spin electron dominates when μ′<2.4, but such a phenomenon is not found for μ′>2.4. We have pointed out that the present MS/I/S tunneling junction seems to work as a switching device in which the ↑ and ↓ spin flows can be easily controlled by the external magnetic field.

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Demirtaş, Abdullah Orhan. "Tp-e interval and Tp-e/QTc ratio are significantly increased in patients with brain death." Acta Medica 50, no. 3 (September 30, 2019): 25–31. http://dx.doi.org/10.32552/2019.actamedica.363.

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Objective: We aimed to investigate whether there is a change in Tpe interval, Tpe/QT and Tpe/QTc ratios in patients with brain death. Materials and Methods: Fifty brain death patients and 50 age and sex matched healthy controls were included in the study. In addition to routine evaluation, Tp-e interval, Tp-e / QT and Tp-e / QTc ratios were measured in 12-lead electrocardiography. Tp-e was measured in the precordial leads using the Tail method; the time from the peak of the T wave to the point where the wave reached the isoelectric line. Results: White blood cell, aspartate aminotransferase, alanine aminotransferase and high sensitive c reactive protein levels were significantly higher in patients with brain death. The frequency of patients with QTc prolongation, Tp-e interval, Tp-e/QT and Tp-e/QTc values were significantly higher in patients with brain death (p <0.05). Tp-e interval, Tp-e/QT and Tp-e/QTc values were found to be positively correlated with HsCRP (p<0.001 for all). The cutoff value of Tpe/QT ratio obtained by ROC curve analysis was 0.225 for prediction of brain death (sensitivity: 64.0%, specificity: 84.0%). The area under the curve (AUC) was 0.824 (p<0.001). Conclusion: Tp-e interval, Tp-e / QT and Tp-e / QTc ratios are increased in patients with brain death compared to healthy controls. This may be related to the effect of the changing neuroendocrine state in patients with brain death.

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Calderillo, G., C. Cano, J. M. Ruiz, J. Zamora, H. Lopez, J. Martinez, and D. Gallardo. "Chemoradiotherapy in anal carcinoma using cisplatin and 5FU." Journal of Clinical Oncology 24, no. 18_suppl (June 20, 2006): 14128. http://dx.doi.org/10.1200/jco.2006.24.18_suppl.14128.

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14128 Background: Chemoradiation (CRT) is now established as the primary treatment for anal carcinoma. The original combination was 5Fu and mitomycin C, but the cisplatin may offer better local control than the standar of MMC with toxicity more tolerable. Methods: Between March 2000 and January 2005, 25 patients with anal carcinoma advanced with non pre-treated were enrolled. Eligible patients had an ECOG PS 0–2. They received cisplatin 80–100 mg/m2 day 1 and 5FU 800–1000 mg/m2 day 1–4 every 4 weeks and radiotherapy >45 Gys. Results: 25 patients, 12 male and 13 female, median age 63 (range 36–83 y). 22 with squamous cell carcinoma and 3 adenocarcinoma. (A) 11 patients recieved QT concurrente with RT, median cycles 2 and median of RT 50 Gys and (B) 14 patients recieved QT follow QT-RT concurrent, median cycles 3.5 and median of RT 48 Gys. The toxicity 3–4 were: neutropenia 23%, anaemia 4%, trombocytopenia 8%, diarrhea 15%, vomiting and nausea 19%. The evaluation: (RC) (64%), (RP) (28%) and PD (8%). The median survival 15.5 m (9–42 m), 12 m group A vs 16 m group B. Conclusions: The combination RT-QT with cisplatin and 5FU is feasible and tolerable, and may offer more the secuencie QT follow CRT. No significant financial relationships to disclose.

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Asfaw, Teffera M. "A New Topological Degree Theory for Perturbations of Demicontinuous Operators and Applications to Nonlinear Equations with Nonmonotone Nonlinearities." Journal of Function Spaces 2016 (2016): 1–15. http://dx.doi.org/10.1155/2016/3970621.

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Let X be a real reflexive locally uniformly convex Banach space with locally uniformly convex dual space X⁎. Let T:X⊇DT→2X⁎ be maximal monotone of type Γdϕ (i.e., there exist d≥0 and a nondecreasing function ϕ:0,∞→0,∞ with ϕ(0)=0 such that 〈v⁎,x-y〉≥-dx-ϕy for all x∈DT, v⁎∈Tx, and y∈X),L:X⊃D(L)→X⁎ be linear, surjective, and closed such that L-1:X⁎→X is compact, and C:X→X⁎ be a bounded demicontinuous operator. A new degree theory is developed for operators of the type L+T+C. The surjectivity of L can be omitted provided that RL is closed, L is densely defined and self-adjoint, and X=H, a real Hilbert space. The theory improves the degree theory of Berkovits and Mustonen for L+C, where C is bounded demicontinuous pseudomonotone. New existence theorems are provided. In the case when L is monotone, a maximality result is included for L and L+T. The theory is applied to prove existence of weak solutions in X=L20,T;H01Ω of the nonlinear equation given by ∂u/∂t-∑i=1N(∂/∂xi)Aix,u,∇u+Hλx,u,∇u=fx,t, x,t∈QT; ux,t=0, x,t∈∂QT; and ux,0=ux,T, x∈Ω, where λ>0, QT=Ω×0,T, ∂QT=∂Ω×0,T, Aix,u,∇u=∂/∂xiρx,u,∇u+aix,u,∇u (i=1,2,…,N), Hλx,u,∇u=-λΔu+gx,u,∇u, Ω is a nonempty, bounded, and open subset of RN with smooth boundary, and ρ,ai,g:Ω¯×R×RN→R satisfy suitable growth conditions. In addition, a new existence result is given concerning existence of weak solutions for nonlinear wave equation with nonmonotone nonlinearity.

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Alkhallaf, S., H. Cornille, B. Markowska, Z. Lankri, and N. Delepine. "Voriconazole-induced QT-corrected (QTc) interval prolongation, bradycardia, hypothermia, mydriasis in an immunosuppressed patient with Ewing." Journal of Clinical Oncology 27, no. 15_suppl (May 20, 2009): e20738-e20738. http://dx.doi.org/10.1200/jco.2009.27.15_suppl.e20738.

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e20738 Background: Invasive aspergillosis is an important cause of increased mortality and morbidity in immunocompromised patients. Early treatment of probable aspergillosis by voriconazole is recommended by many authors. Nevertheless direct possible lethal complications must be taken into account. Methods: we describe a case of voriconazole adverse events in a 18 y old patient treated for aplasia by antibiotics and caspofungin. He remained febrile: Voriconazole initiated for digestive mycosis, caugh, endemic aspergillosis. Second injection was badly tolerated ( fever 40 °, dyspnea, chills, myalgias, hypotension) leading to stop Voriconazole. Few hours later, bradycardia (36 bpm/mn), QT c interval prolongation (QTc 482ms), bilateral mydriasis, hypothermia appeared. Others risks for cardiac events were studied: prior cardiotoxic chemotherapy; lightly low calcemia and magnesemia, negative T ondes, traducing major potassium deficit in cardiac cells, in spite of initially normal kaliemia (4.6 mmol/l) mild hypokalemia (3.3 meq/l). Systemic infection was eliminated, cerebral MRI normal, blood dosage of voriconazole at 80 h and 96 h after last dose negative. We discontinued potentially arrhythmogenic drugs. Specific treatment consisted of electrolyte disturbances correction, IV atropine, scopolamine patch. 24 h holter ECG revealed neither torsades de pointes nor ventricular tachycardia. QT c interval remained longer for 3 days. Onde T was normalised at day 6, with disappearance of bradycardia and hypothermia,without any cardiac event. Results: Azole family antifungal agents were pointed out as arrhythmogenic (QTc prolongation, torsades de pointes) in combination or alone. Few data reported bradycardia and QT c prolongation with voriconazole, although the drug package insert warns about such reactions. Furthermore, none case of mydriasis was reported but noted in Pfizer American data file(< 2% of case). Conclusions: Careful monitoring of QTc prolongation and bradycardia in patients receiving voriconazole is mandatory, particularly those with electrolyte disturbances, concomitant QT prolonging drugs, and /or receiving toxic cardiac chemotherapy. No significant financial relationships to disclose.

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Toib, Amir, Chen Zhang, Giulia Borghetti, Xiaoxiao Zhang, Markus Wallner, Yijun Yang, Constantine D. Troupes, et al. "Remodeling of repolarization and arrhythmia susceptibility in a myosin-binding protein C knockout mouse model." American Journal of Physiology-Heart and Circulatory Physiology 313, no. 3 (September 1, 2017): H620—H630. http://dx.doi.org/10.1152/ajpheart.00167.2017.

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Hypertrophic cardiomyopathy (HCM) is one of the most common genetic cardiac diseases and among the leading causes of sudden cardiac death (SCD) in the young. The cellular mechanisms leading to SCD in HCM are not well known. Prolongation of the action potential (AP) duration (APD) is a common feature predisposing hypertrophied hearts to SCD. Previous studies have explored the roles of inward Na+ and Ca2+ in the development of HCM, but the role of repolarizing K+ currents has not been defined. The objective of this study was to characterize the arrhythmogenic phenotype and cellular electrophysiological properties of mice with HCM, induced by myosin-binding protein C (MyBPC) knockout (KO), and to test the hypothesis that remodeling of repolarizing K+ currents causes APD prolongation in MyBPC KO myocytes. We demonstrated that MyBPC KO mice developed severe hypertrophy and cardiac dysfunction compared with wild-type (WT) control mice. Telemetric electrocardiographic recordings of awake mice revealed prolongation of the corrected QT interval in the KO compared with WT control mice, with overt ventricular arrhythmias. Whole cell current- and voltage-clamp experiments comparing KO with WT mice demonstrated ventricular myocyte hypertrophy, AP prolongation, and decreased repolarizing K+ currents. Quantitative RT-PCR analysis revealed decreased mRNA levels of several key K+ channel subunits. In conclusion, decrease in repolarizing K+ currents in MyBPC KO ventricular myocytes contributes to AP and corrected QT interval prolongation and could account for the arrhythmia susceptibility. NEW & NOTEWORTHY Ventricular myocytes isolated from the myosin-binding protein C knockout hypertrophic cardiomyopathy mouse model demonstrate decreased repolarizing K+ currents and action potential and QT interval prolongation, linking cellular repolarization abnormalities with arrhythmia susceptibility and the risk for sudden cardiac death in hypertrophic cardiomyopathy.

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Batchvarov, V. N., K. Hnatkova, A. J. Camm, and M. Malik. "A18-4 Long-term stability of the individual QT/RR relationship." EP Europace 4, Supplement_2 (December 1, 2003): B27. http://dx.doi.org/10.1016/eupace/4.supplement_2.b27-c.

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Donger, Claire, Isabelle Denjoy, Myriam Berthet, Nathalie Neyroud, Corinne Cruaud, Mohammed Bennaceur, Guy Chivoret, Ketty Schwartz, Philippe Coumel, and Pascale Guicheney. "KVLQT1 C-Terminal Missense Mutation Causes a Forme Fruste Long-QT Syndrome." Circulation 96, no. 9 (November 4, 1997): 2778–81. http://dx.doi.org/10.1161/01.cir.96.9.2778.

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Karahan, Zulkuf, Murat Ugurlu, Berzal Ucaman, Ali Veysel Ulug, Ilyas Kaya, Kemal Cevik, Mehmet Sahin Adiyaman, Onder Oztürk, Hikmet Iyem, and Ferit Ozdemir. "Association Between ACE Gene Polymorphism and QT Dispersion in Patients with Acute Myocardial Infarction." Open Cardiovascular Medicine Journal 10, no. 1 (May 31, 2016): 117–21. http://dx.doi.org/10.2174/1874192401610010117.

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Background: Angiotensin converting enzyme (ACE) gene polymorphism is associated with high renin-angiotensin system causing myocardial fibrosis and ventricular repolarization abnormality. Based on these findings, this study was designed to determine the association between ACE gene insertion/deletion (I/D) polymorphism and QT dispersion after acute myocardial infarction (MI). Objective and Methods: The study included 108 patients with acute MI. Blood samples were obtained from all the patients for genomic DNA analysis. ECGs were recorded at baseline and at the end of a 6-month follow up. The OT dispersion was manually calculated. Results: The mean age of the patients was 57.5 ±9.9 years (ranging from 36 to 70). The patients with DD genotype showed longer QT dispersion than patients with II or DI genotype at the baseline, while at the end of the six-month follow up the patients with DI genotype showed longer QT dispersion than patients with DD or II genotypes. However, the magnitude of the QT dispersion prolongation was higher in patients carrying the ACE D allele than patients who were not carrying it, at baseline and at the end of six-month follow up (52.5 ±2.6 msn vs. 47.5±2.1 msn at baseline, 57±3.2 msn vs. 53±2.6 msn in months, P: 0.428 and P: 0.613, respectively). Conclusion: Carriers of the D allele of ACE gene I/D polymorphism may be associated with QT dispersion prolongation in patients with MI.An interaction of QT dispersion and ACE gene polymorphism may be associated with an elevation of serum type I-C terminal pro-collagen concentration, possibly leading to myocardial fibrosis, and increased action potential duration.

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Hübschle, Christian B., George M. Sheldrick, and Birger Dittrich. "ShelXle: a Qt graphical user interface forSHELXL." Journal of Applied Crystallography 44, no. 6 (November 12, 2011): 1281–84. http://dx.doi.org/10.1107/s0021889811043202.

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ShelXleis a graphical user interface forSHELXL[Sheldrick, G. M. (2008).Acta Cryst.A64, 112–122], currently the most widely used program for small-molecule structure refinement. It combines an editor with syntax highlighting for theSHELXL-associated .ins (input) and .res (output) files with an interactive graphical display for visualization of a three-dimensional structure including the electron density (Fo) and difference density (Fo–Fc) maps. Special features ofShelXleinclude intuitive atom (re-)naming, a strongly coupled editor, structure visualization in various mono and stereo modes, and a novel way of displaying disorder extending over special positions.ShelXleis completely compatible with all features ofSHELXLand is written entirely in C++ using the Qt4 and FFTW libraries. It is available at no cost for Windows, Linux and Mac-OS X and as source code.

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Iserles, A. "On the generalized pantograph functional-differential equation." European Journal of Applied Mathematics 4, no. 1 (March 1993): 1–38. http://dx.doi.org/10.1017/s0956792500000966.

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The generalized pantograph equation y′(t) = Ay(t) + By(qt) + Cy′(qt), y(0) = y0, where q ∈ (0, 1), has numerous applications, as well as being a useful paradigm for more general functional-differential equations with monotone delay. Although many special cases have been already investigated extensively, a general theory for this equation is lacking–its development and exposition is the purpose of the present paper. After deducing conditions on A, B, C ∈ ℂd×d that are equivalent to well-posedness, we investigate the expansion of y in Dirichlet series. This provides a very fruitful form for the investigation of asymptotic behaviour, and we duly derive conditions for limt⋅→∞y(t) = 0. The behaviour on the stability boundary possesses no comprehensive explanation, but we are able to prove that, along an important portion of that boundary, y is almost periodic and, provided that q is rational, it is almost rotationally symmetric. The paper also addresses itself to a detailed analysis of the scalar equation y′(t) = by(qt), y(0) = 1, to high-order pantograph equations, to a phenomenon, similar to resonance, that occurs for specific configurations of eigenvalues of A, and to the equation Y′(t) = AY(t) + Y(qt) B, Y(0) = Y0.

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Eisenberg, Susan J., Navneet Dullet, Michael D. Lesh, and Melvin M. Scheinman. "Polymorphous ventricular tachycardia in patients with normal cardiac function and QT interval." Journal of the American College of Cardiology 17, no. 2 (February 1991): A198. http://dx.doi.org/10.1016/0735-1097(91)91760-c.

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Stein, Kenneth M., Claudine Fenton, Anne Marie Lehany, Peter M. Okin, and Paul Kligfield. "Incidence of QT interval prolongation during pentamidine therapy of Pneumocystis carinii pneumonia." American Journal of Cardiology 68, no. 10 (October 1991): 1091–94. http://dx.doi.org/10.1016/0002-9149(91)90502-c.

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36

Boulay, Emmanuel, Eric Troncy, Michael V. Accardi, Michael K. Pugsley, Anne-Marie Downey, Lois Miraucourt, Hai Huang, et al. "Confounders and Pharmacological Characterization When Using the QT, JTp, and Tpe Intervals in Beagle Dogs." International Journal of Toxicology 39, no. 6 (October 16, 2020): 530–41. http://dx.doi.org/10.1177/1091581820954865.

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Introduction: Corrected QT (QTc) interval is an essential proarrhythmic risk biomarker, but recent data have identified limitations to its use. The J to T-peak (JTp) interval is an alternative biomarker for evaluating drug-induced proarrhythmic risk. The aim of this study was to evaluate pharmacological effects using spatial magnitude leads and DII electrocardiogram (ECG) leads and common ECG confounders (ie, stress and body temperature changes) on covariate adjusted QT (QTca), covariate adjusted JTp (JTpca), and covariate adjusted T-peak to T-end (Tpeca) intervals. Methods: Beagle dogs were exposed to body hyper- (42 °C) or hypothermic (33 °C) conditions or were administered epinephrine to assess confounding effects on heart rate corrected QTca, JTpca, and Tpeca intervals. Dofetilide (0.1, 0.3, 1.0 mg/kg), ranolazine (100, 140, 200 mg/kg), and verapamil (7, 15, 30, 43, 62.5 mg/kg) were administered to evaluate pharmacological effects. Results: Covariate adjusted QT (slope −12.57 ms/°C) and JTpca (−14.79 ms/°C) were negatively correlated with body temperature but Tpeca was minimally affected. Epinephrine was associated with QTca and JTpca shortening, which could be related to undercorrection in the presence of tachycardia, while minimal effects were observed for Tpeca. There were no significant ECG change following ranolazine administration. Verapamil decreased QTca and JTpca intervals and increased Tpeca, whereas dofetilide increased QTca and JTpca intervals but had inconsistent effects on Tpeca. Conclusion: Results highlight potential confounders on QTc interval, but also on JTpca and Tpeca intervals in nonclinical studies. These potential confounding effects may be relevant to the interpretation of ECG data obtained from nonclinical drug safety studies with Beagle dogs.

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Genovesi, Simonetta, Daniela M. Prata Pizzala, Massimo Pozzi, Laura Ratti, Maria Milanese, Federico Pieruzzi, Antonio Vincenti, Andrea Stella, Giuseppe Mancia, and Marco Stramba-Badiale. "QT interval prolongation and decreased heart rate variability in cirrhotic patients: relevance of hepatic venous pressure gradient and serum calcium." Clinical Science 116, no. 12 (May 14, 2009): 851–59. http://dx.doi.org/10.1042/cs20080325.

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A prolongation of QT interval has been shown in patients with cirrhosis and it is considered as part of the definition of the so-called ‘cirrhotic cardiomyopathy’. The aim of the present study was to assess the determinants of QT interval prolongation in cirrhotic patients. Forty-eight male patients with different stages of liver disease were divided into three subgroups according to the Child–Pugh classification. All patients underwent a 24-h ECG Holter recording. The 24-h mean of QT intervals corrected for heart rate (termed QTc) and the slope of the regression line QT/RR were calculated. HRV (heart rate variability), plasma calcium and potassium concentration and HVPG (hepatic venous pressure gradient) were measured. QTc was progressively prolonged from Child A to Child C patients (P=0.001). A significant correlation between QTc and HVPG was found (P=0.003). Patients with alcohol-related cirrhosis presented QTc prolongation more frequently than patients with post-viral cirrhosis (P<0.001). The QT/RR slope was steeper in subjects with alcoholic aetiology as compared with viral aetiology (P=0.02), suggesting that these patients have a further QTc prolongation when heart rate decreases. The plasma calcium concentration was inversely correlated with QTc (P<0.001). The presence of severe portal hypertension was associated with decreased HRV (P<0.001). Cirrhotic patients with a more severe disease, especially of alcoholic aetiology, who have greater HVPG and lower calcium plasma levels, have an altered ventricular repolarization and a reduced vagal activity to the heart, which may predispose to life-threatening arrhythmias.

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MacKenzie, Marius A., Wim R. M. Aengevaeren, Ad R. M. M. Hermus, Tjeerd van der Werf, Gerlach F. F. M. Pieters, Anthony G. H. Smals, and Peter W. C. Kloppenborg. "Electrocardiographic changes during steady mild hypothermia and normothermia in patients with poikilothermia." Clinical Science 82, no. 1 (January 1, 1992): 39–45. http://dx.doi.org/10.1042/cs0820039.

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1. ECG changes observed in short-term induced and accidental hypothermia are well known. To assess the influence of steady-state spontaneous hypothermia on the ECG, we subjected four patients with acquired poikilothermia (severe thermolability) to 24 h ECG recording, exercise testing and thermal stress. 2. Twenty-four hour Holter monitoring showed a significant reduction in heart rate and a prolongation of the QT interval during steady-state mild hypothermia (rectal temperature 33.9 ± 0.7°C, mean ± sd) compared with during normothermia; no significant changes occurred in the PR interval, QRS complex and QTc interval (QT interval corrected for heart rate). 3. Unlike during normothermia, during steady hypothermia atrioventricular Wenckebach blocks were observed in two patients, whereas another patient showed markedly more atrioventricular Wenckebach blocks during hypothermia. 4. During steady hypothermia the heart rate variability was significantly enhanced in comparison with normothermia. 5. Exercise tolerance was similar during mild hypothermia and normothermia. 6. Heat exposure (ambient temperature 40°C) induced significantly greater changes in rectal temperature, heart rate and PR interval, QRS complex and QT interval in the patients than in the control subjects (n = 8). 7. The present study reveals that even mild steady spontaneous hypothermia can elicit ECG changes, presumably mediated by relatively enhanced cardiac vagal tone. Hence, spontaneous abnormalities in core temperature should be taken into account in interpreting the ECG in clinical practice.

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Monteiro, Felipe R., Mário A. P. Garcia, Lucas C. Cordeiro, and Eddie B. de Lima Filho. "Bounded model checking of C++ programs based on the Qt cross-platform framework." Software Testing, Verification and Reliability 27, no. 3 (March 2, 2017): e1632. http://dx.doi.org/10.1002/stvr.1632.

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Ohno, Seiko, Dimitar P. Zankov, Hidetada Yoshida, Keiko Tsuji, Takeru Makiyama, Hideki Itoh, Masaharu Akao, Jules C. Hancox, Toru Kita, and Minoru Horie. "N- and C-terminal KCNE1 mutations cause distinct phenotypes of long QT syndrome." Heart Rhythm 4, no. 3 (March 2007): 332–40. http://dx.doi.org/10.1016/j.hrthm.2006.11.004.

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41

Hosseini, Meisam, Jose Vicente, Lars Johannesen, Alexander Wong, Dustin C. McAfee, Norman Stockbridge, and David G. Strauss. "Map of thorough QT studies with QTc and J-T peak c biomarkers." Journal of Electrocardiology 51, no. 1 (January 2018): e3. http://dx.doi.org/10.1016/j.jelectrocard.2017.12.013.

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Khalil, Osama Ahmed, Mohamed Samy Fawzy, Ashraf Khalifa EL-Naggar, and Entesar Kamel Sayed. "Evaluation of QT Intervals in Compensated and Decompensated Chronic Hepatitis C Cirrhotic Patients." Egyptian Journal of Hospital Medicine 79, no. 1 (April 1, 2020): 435–41. http://dx.doi.org/10.21608/ejhm.2020.80836.

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43

Adlan, Ahmed M., Vasileios F. Panoulas, Jacqueline P. Smith, James P. Fisher, and George D. Kitas. "Association Between Corrected QT Interval and Inflammatory Cytokines in Rheumatoid Arthritis." Journal of Rheumatology 42, no. 3 (January 15, 2015): 421–28. http://dx.doi.org/10.3899/jrheum.140861.

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Objective.Corrected QT (QTc) interval predicts all-cause and cardiovascular mortality and may contribute to the increased mortality risk in rheumatoid arthritis (RA). Animal experiments have shown that proinflammatory cytokines [tumor necrosis factor (TNF)-α and interleukin 1 (IL-1)] can prolong cardiomyocyte action potential. We sought to determine whether elevations in circulating inflammatory cytokines were independently associated with QTc prolongation in patients with RA.Methods.One hundred twelve patients [median age 62 (interquartile range 17) yrs; 80 women (71%)] from a well-characterized RA cohort underwent baseline 12-lead electrocardiograms for QT interval measurement and contemporary blood sampling to assess concentrations of inflammatory markers including C-reactive protein (CRP), TNF-α, and interleukins (IL-1α, IL-1β, IL-6, IL-10). QTc was calculated using the Bazett (QTBAZ= QT ÷ √RR) and Framingham Heart Study (QTFHS= QT + 0.154 × [1 – RR]) heart rate correction formulas.Results.Inflammatory cytokines (TNF-α, IL-1β, IL-6, IL-10) were positively correlated with QTBAZ(Spearman rank correlation coefficient rho = 0.199, 0.210, 0.222, 0.333; all p < 0.05). In multivariable regression analysis, these associations were all confounded by age except IL-10, where higher tertile groups were independently and positively associated with QTBAZ(β = 0.202, p = 0.023) and QTFHS(β = 0.223, p = 0.009) when compared to the lower tertile. CRP (per unit increase) was independently associated with QTBAZ(β = 0.278, p = 0.001), but not QTFHS.Conclusion.To our knowledge, ours is the first study demonstrating a contemporary link between inflammatory cytokines and QT interval in humans. Our results suggest that a lower inflammatory burden may protect against QTc prolongation in patients with RA. However, further studies are required to confirm the effects of pro- and antiinflammatory cytokines on QTc interval.

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Dimitriu, Alexandru Grigore, Cristina Mandric, and Lavinia Dimitriu. "0534: Utility of research of the QT/QT-c intervals dispersion and cardiac biomarkers for early diagnosis of anthracycline induced cardiotoxicity in children." Archives of Cardiovascular Diseases Supplements 8, no. 1 (January 2016): 24. http://dx.doi.org/10.1016/s1878-6480(16)30072-6.

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Musialik-Lydka, A., B. Sredniawa, T. Zielinska, P. Jarski, Z. Kalarus, and L. Polonski. "A16-4 Non-dipping hypertensive subjects and left ventricular hypertrophy and qt dispersion." EP Europace 4, Supplement_2 (December 1, 2003): B24. http://dx.doi.org/10.1016/eupace/4.supplement_2.b24-c.

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Sun, Lei, Sergey Yagoda, Hongqi Xue, Randy Brown, Narinder Nangia, David McDonnell, Bhaskar Rege, Lisa von Moltke, and Borje Darpo. "143 A Combination of Olanzapine and Samidorphan Has No Clinically Relevant Effect on QT Prolongation up to Supratherapeutic Doses." CNS Spectrums 25, no. 2 (April 2020): 291. http://dx.doi.org/10.1017/s1092852920000590.

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Abstract:Background:ALKS 3831, a combination of olanzapine and samidorphan (OLZ/SAM) in development for schizophrenia, is intended to mitigate olanzapine-associated weight gain. This thorough QT (tQT) study evaluated OLZ/SAM effects on electrocardiogram parameters.Methods:In this randomized, double-blind, parallel-group study, 100 patients with stable schizophrenia were randomized 3:2 to either receive OLZ/SAM 10/10 mg (therapeutic dose) on days 2–4, 20/20 mg on days 5–8, and 30/30 mg (supratherapeutic dose) on days 9–13 with moxifloxacin-matching placebo on days 1 and 14, or a single dose of moxifloxacin 400 mg and matching placebo on days 1 and 14 (nested crossover design). Drug concentration relation to change from baseline in Fridericia-corrected QTc (ΔQTcF) was evaluated using a linear mixed-effect concentration-QTc (C-QTc) model. Adverse events were assessed.Results:The slope (90% CI) of the C-QTc was not significant for olanzapine or samidorphan (0.03 [−0.01, 0.08] and 0.01 [−0.01, 0.04] msec per ng/mL, respectively). Predicted placebo-corrected ΔQTcF (90% CI) was 2.33 (−2.72, 7.38) and 1.38 (−3.37, 6.12) msec at the observed geometric mean maximal concentration of olanzapine (62.6 ng/mL) and samidorphan (75.1 ng/mL), respectively, on day 13. A clinically relevant QT effect (ie, placebo-corrected ΔQTcF ≥10 msec) can be excluded for olanzapine and samidorphan concentrations up to ≈110 and ≈160 ng/mL, respectively. Assay sensitivity was confirmed by the C-QTc relationship of moxifloxacin. OLZ/SAM was well tolerated.Conclusions:OLZ/SAM, in doses and plasma concentrations up to supratherapeutic levels, was well tolerated and had no clinically relevant effects on electrocardiogram parameters, including QT interval, in patients with schizophrenia.Funding Acknowledgements:This study was funded by Alkermes, Inc.

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Armstrong, R. B., M. D. Delp, E. F. Goljan, and M. H. Laughlin. "Progressive elevations in muscle blood flow during prolonged exercise in swine." Journal of Applied Physiology 63, no. 1 (July 1, 1987): 285–91. http://dx.doi.org/10.1152/jappl.1987.63.1.285.

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Distribution of muscle blood flow has not been measured in man during prolonged exercise, but progressive elevations in skin flow coupled with constant cardiac output (QT) have suggested muscle blood flow may be compromised. However, previous experiments with rats demonstrated progressive increases in muscle blood flow over time during prolonged submaximal exercise. The present study was performed to study muscle blood flow in miniature swine during long-term exercise to shed light on this apparent anomaly. QT and distribution of QT were studied with radiolabeled microspheres while pigs ran on a level treadmill at a speed (10.5 km/h) requiring 71 +/- 4% of maximal O2 consumption (VO2 max). QT increased 23% from the 5th to the 30th min of exercise, whereas total skeletal muscle flow increased by 49%. Increases in flow in the muscles resulted from decreased resistance, since mean arterial pressure declined over this time period (-7%). In addition, the proportional increases in muscle flow were similar within synergistic muscle groups independent of fiber type composition (e.g., elbow extensors: 59–78%; elbow flexors: 26–40%). The factor that limited continued exercise appeared to be body temperature. Colonic temperature rose in linear fashion over time; the animals became exhausted at approximately 42 degrees C. These flow data are similar to previous findings in rats and indicate that during prolonged treadmill locomotion in quadrupedal animals muscle blood flow increases over time to near maximal levels.

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Yin, Jing, Wei Gu, Xiao Fang Yang, and Chuan Hua Li. "Design of QT-4.7 LAN Chat System Based on ARM Linux." Advanced Materials Research 926-930 (May 2014): 1906–9. http://dx.doi.org/10.4028/www.scientific.net/amr.926-930.1906.

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Instant messaging technologies are becoming more and more mature as network gains popularity and develops rapidly. Instant messaging software such as QQ and Wechat from Tencent, Mitalk and YY Voice are based on C/S mode. In this paper, after completing software development, the platform is migrated and its kernel recompiled. After building root file system and migrating relevant library files, it not only resolves the problems such as Chi-nese gibberish and missing input method after migration, but also designs an instant messaging software for enterprises similar to IP messenger through P2P technology and C++ pro-gramming in QT framework based on Socket communication mechanism, thus realizing messaging and file transfer within LAN.

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Fialová, Kateřina, Jiří Blahák, Marek Motola, Jiří Jarkovský, Jan Mužík, and Marie Nováková. "Effect of perphenazine on electrogram of rat isolated heart." Acta Veterinaria Brno 80, no. 1 (2011): 87–92. http://dx.doi.org/10.2754/avb201180010087.

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The aim of this study was to clarify whether administration of antipsychotic perphenazine contributes to the electrophysiological changes of the isolated heart. Fourteen adult male Wistar rats were divided into two groups. Langendorff hearts were perfused with Krebs-Henseleit solution at constant pressure (85 mmHg) and 37 °C (CaCl2, 1.2 mM). The electrogram was recorded by touch-free method. The hearts of the first group were exposed to 3.10-5 M perphenazine, the hearts of the second group to 3.10-8 M perphenazine. The incidence of arrhythmias and the heart rate and QT interval changes were studied on electrogram during 30 min periods of control, the first perphenazine administration, washout, and the second drug administration. Perphenazine administration significantly prolonged QT (p < 0.001) and QTc (p < 0.05) in group 1. In group 2, QT and QTc prolongation was less pronounced (p < 0.05). A number of arrhythmias appeared, from single premature ventricular complexes to more severe ones in both groups. The heart rate changes were non-significant. We conclude that although phenothiazines are still medicaments of choice in certain psychoses, their cardiovascular side effects should be always taken in consideration.

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Bandorski, Dirk, Reinhard Hoeltgen, Nicole Becker, Winfried Padberg, Harilaos Bogossian, Christoph Wiedenroth, Matthias Arlt, et al. "Follow-Up (Measurement) of Corrected QT Interval in Adult Patients before and after Lung Transplantation." BioMed Research International 2017 (2017): 1–5. http://dx.doi.org/10.1155/2017/4519796.

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Background. Prolongation of the corrected QT (QTc) interval is well known for many drugs, some of which are an integral part of the therapeutic regimen after lung transplantation (LTX). Therefore, we investigated the QTc interval after LTX in the present study. Patients and Methods. The medical records of patients after LTX were studied for demographic data, indication of LTX, medication, and baseline and follow-up ECGs. The QT interval was corrected for the patient’s heart rate using the different formulae of Bazett, Fridericia, Hodges, and Framingham. Results. Fifty-nine patients were included. The mean age ± SD was 55.6±7.8 years (median 58 years). After LTX, QTc intervals showed no (relevant) changes during follow-up, even though all patients were treated with drugs (in combination) known to bear a risk of prolonged QTc interval and cortisone. The longest QTc intervals were obtained using Bazett’s formula. Conclusion. The QTc interval did not increase under immunosuppressive medication after LTX in our cohort of patients. We speculate that the concurrent use of cortisone may shorten the QT(c) intervals or cancel out drug-induced prolongation of the QTc interval.

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Journal articles on the topic 'C++ Qt'

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