tbuckley/cabot-search huggingface dataset:
Nonlinear Analysis of the Baroreceptor Reflex System
Authors: William H. Levison, G. Octo Barnett, William D. Jackson
Journal: Circulation Research (1966)

The regulation of blood pressure by the baroreceptor reflex was examined in anesthetized dogs. The receptor feedback path was broken by surgical intervention, the input (carotid sinus pressure) was controlled by an external servo system, and simultaneous records of input and output (systemic arterial pressure) were obtained. A variety of pressure waveforms were applied to the carotid sinus so that the nonlinear behavior could be explored thoroughly. Most of the input waveforms consisted of relatively small signals about an operating point in the normal blood pressure range. The nonlinear behavior of the reflex was illustrated in a number of ways. Square waves, sinusoids, and short pulses produced asymmetric arterial pressure waveforms. An overshoot in the arterial pressure always followed the rising edge of the input square wave, but was generally absent following the negative-going part of the square wave. Either positive or negative pulses caused a transient drop in arterial pressure. The sinusoidal response was often distorted, with the falling portion of the output waveform steeper than the rising portion. The system behaved as a rectifier, or envelope-detector, as illustrated by 1) the decrease in mean arterial pressure when either the amplitude or the frequency of a sinusoidal input was increased and 2) the appearance in the arterial pressure waveform of a component correlated with the envelope of a modulated carrier. Another nonlinear phenomenon was the decrease in low-frequency sinusoidal gain caused by the addition of a high-frequency sinusoid to the sinus pressure waveform. This behavior indicates that if closed loop behavior in the intact animal is to be predicted from the open loop sinewave response, the effects of the cardiac pressure pulse must be considered. A model was constructed from standard electronic components to simulate the input-output behavior of the baroreceptor reflex. The model was able to simulate the response to high- and low-frequency sinusoids and to reproduce the essential features of the square-wave and pulse responses. On this basis the model was considered adequate for simulating the performance of the baroreceptor reflex in certain open loop and closed loop situations.
Rate Asymmetry After Genome Duplication Causes Substantial Long-Branch Attraction Artifacts in the Phylogeny of Saccharomyces Species
Authors: Mario A. Fares, Kevin P. Byrne, Kenneth H. Wolfe
Journal: Molecular Biology and Evolution (2005)

Whole-genome duplication (WGD) produces sets of gene pairs that are all of the same age. We therefore expect that phylogenetic trees that relate these pairs to their orthologs in other species should show a single consistent topology. However, a previous study of gene pairs formed by WGD in the yeast Saccharomyces cerevisiae found conflicting topologies among neighbor-joining (NJ) trees drawn from different loci and suggested that this conflict was the result of “asynchronous functional divergence” of duplicated genes (Langkjaer, R. B., P. F. Cliften, M. Johnston, and J. Piskur. 2003. Yeast genome duplication was followed by asynchronous differentiation of duplicated genes. Nature421:848–852). Here, we test whether the conflicting topologies might instead be due to asymmetrical rates of evolution leading to long-branch attraction (LBA) artifacts in phylogenetic trees. We constructed trees for 433 pairs of WGD paralogs in S. cerevisiae with their single orthologs in Saccharomyces kluyveri and Candida albicans. We find a strong correlation between the asymmetry of evolutionary rates of a pair of S. cerevisiae paralogs and the topology of the tree inferred for that pair. Saccharomyces cerevisiae gene pairs with approximately equal rates of evolution tend to give phylogenies in which the WGD postdates the speciation between S. cerevisiae and S. kluyveri (B-trees), whereas trees drawn from gene pairs with asymmetrical rates tend to show WGD pre-dating this speciation (A-trees). Gene order data from throughout the genome indicate that the “A-trees” are artifacts, even though more than 50% of gene pairs are inferred to have this topology when the NJ method as implemented in ClustalW (i.e., with Poisson correction of distances) is used to construct the trees. This LBA artifact can be ameliorated, but not eliminated, by using gamma-corrected distances or by using maximum likelihood trees with robustness estimated by the Shimodaira-Hasegawa test. Tests for adaptive evolution indicated that positive selection might be the cause of rate asymmetry in a substantial fraction (19%) of the paralog pairs.
Reconstitution of the functional receptors for murine and human interleukin 5.
Authors: S Takaki, Y Murata, T Kitamura, A Miyajima, A Tominaga, K Takatsu
Journal: The Journal of Experimental Medicine (1993)

The murine interleukin 5 receptor (mIL-5R) is composed of two distinct subunits, alpha and beta. The alpha subunit (mIL-5R alpha) specifically binds IL-5 with low affinity. The beta subunit (mIL-5R beta) does not bind IL-5 by itself, but forms the high-affinity receptor with mIL-5R alpha. mIL-5R beta has been revealed to be the mIL-3R-like protein, AIC2B which is shared with receptors for IL-3 and granulocyte/macrophage colony-stimulating factor. We demonstrated here the reconstitution of the functional receptors for murine and human IL-5 on the mouse IL-2-dependent cell line, CTLL-2. CTLL-2 was transfected with the cDNAs for mIL-5R alpha and/or AIC2B. Only CTLL-2 transfectant expressing both mIL-5R alpha and AIC2B expressed the high-affinity receptor and proliferated in response to murine IL-5. Then CTLL-2 was transfected with the cDNAs for hIL-5R alpha and/or KH97 (beta c), the human homologue of AIC2B. Though beta c did not contribute much to binding affinity of hIL-5R, only CTLL-2 transfectant expressing both hIL-5R alpha and beta c proliferated in response to human IL-5. These results showed that the beta subunit is indispensable in IL-5 signal transduction. We further investigated the function of IL-5-specific alpha subunit in transmitting IL-5 signals. Mutant mIL-5R alpha, which lacks its whole cytoplasmic domain, was transfected into mouse IL-3-dependent cell line, FDC-P1 expressing AIC2B intrinsically. The resulting transfectant did not respond to IL-5, though the transfectant expressed the high-affinity IL-5R, indicating that the cytoplasmic portion of the alpha subunit also has some important role in IL-5-mediated signal transduction.
The Changing HIV Epidemic in Mexico
Authors: Larry R. Kirkland
Journal: JAMA (2008)

Our website uses cookies to enhance your experience. By continuing to use our site, or clicking "Continue," you are agreeing to our Cookie Policy | Continue JAMA HomeNew OnlineCurrent IssueFor Authors Publications JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry (1919-1959) Podcasts Clinical Reviews Editors' Summary Medical News Author Interviews More JN Learning / CMESubscribeJobsInstitutions / LibrariansReprints & Permissions Terms of Use | Privacy Policy | Accessibility Statement 2023 American Medical Association. All Rights Reserved Search All JAMA JAMA Network Open JAMA Cardiology JAMA Dermatology JAMA Forum Archive JAMA Health Forum JAMA Internal Medicine JAMA Neurology JAMA Oncology JAMA Ophthalmology JAMA Otolaryngology–Head & Neck Surgery JAMA Pediatrics JAMA Psychiatry JAMA Surgery Archives of Neurology & Psychiatry Input Search Term Sign In Individual Sign In Sign inCreate an Account Access through your institution Sign In Purchase Options: Buy this article Rent this article Subscribe to the JAMA journal
Flexible Long-Range Loops in the VH Gene Region of the Igh Locus Facilitate the Generation of a Diverse Antibody Repertoire
Authors: Jasna Medvedovic, Anja Ebert, Hiromi Tagoh, Ido M. Tamir, Tanja A. Schwickert, Maria Novatchkova, Qiong Sun, Pim J. Huis in ‘t Veld, Chunguang Guo, Hye Suk Yoon, Yves Denizot, Sjoerd J.B. Holwerda, Wouter de Laat, Michel Cogné, Yang Shi, Frederick W. Alt, Meinrad Busslinger
Journal: Immunity (2013)
Optimization of Hypolipidemic and Antiplatelet Treatment in the Diabetic Patient with Renal Disease
Authors: Mariella Trovati, Franco Cavalot
Journal: Journal of the American Society of Nephrology (2004)

Because diabetes confers a very high risk of cardiovascular morbility and mortality, an aggressive hypolipidemic and antiplatelet treatment has been strongly recommended in the whole diabetic population. In particular, patients who have diabetes should be considered in "secondary prevention" even before presenting cardiovascular events, because diabetes is a "coronary heart disease equivalent." Furthermore, because renal failure is a cardiovascular risk factor per se, patients with diabetes and renal disease present an even greater risk for atherosclerotic vascular events and should be treated even more intensively with hypolipidemic and antiaggregating drugs: the presence of renal impairment does not justify a nihilist therapeutical approach, even if appropriate cautions are mandatory. Finally, dyslipidemia contributes to the deterioration of renal function, a phenomenon potentially prevented by hypolipidemic therapy.
WHO is unfit for health emergencies, says independent panel
Authors: Anne Gulland
Journal: BMJ (2015)

The World Health Organization lacks the capacity and culture to deal with health emergencies, an independent report into WHO’s handling of the Ebola epidemic has found.1

The Ebola Interim Assessment Panel, commissioned by but independent of WHO, has urged large scale reform of the organisation, ruling out setting up a new health emergency agency.

The panel, chaired by the former chief executive of the UK based overseas aid charity Oxfam, Barbara Stocking, said that WHO did not “currently possess the capacity or organisational culture to deliver a full emergency public health response . . . When a health emergency occurs WHO must have the ability to shift into rapid decision making and action and to adapt and adjust its resource allocation methods of work and information practices accordingly.

“The panel really does believe that this is a defining moment for WHO …
Drug-induced Pneumonitis and Heart Failure Simultaneously Associated with Venlafaxine
Authors: Marjolein Drent, Suveer Singh, Anton P. M. Gorgels, David M. Hansell, Otto Bekers, Andrew G. Nicholson, Robert Jan van Suylen, Roland M. du Bois
Journal: American Journal of Respiratory and Critical Care Medicine (2003)

Two cases of interstitial pneumonia with cardiac failure developing in patients treated with the new antidepressant venlafaxine are presented. A strong relationship between the development of the patients' illness and the initiation of venlafaxine treatment was identified. The cytochrome P (CYP) 450 system is involved in the metabolism of venlafaxine, suggesting that alterations in the drug metabolic clearance might be, at least in part, responsible for the development of drug-induced damage in these cases. This might occur either as a consequence of a genetic factor or concomitant drug therapy with an inhibitor of the related CYP system. After identifying the causative agent in the first case, withdrawal of the antidepressant together with corticosteroid treatment led to a favorable outcome. In the other case, the multiorgan failure became fatal. These cases highlight a hitherto undescribed association of an adverse lung reaction and heart failure due to venlafaxine.
Life-Threatening Hemorrhaging in Neonatal Ulcerated Congenital Hemangioma
Authors: Sophie Vildy, Julie Macher, Claire Abasq-Thomas, Catherine Le Rouzic-Dartoy, Francis Brunelle, Dominique Hamel-Teillac, Franck Duteille, Christophe Perret, Pierre Perrot, Elisabeth Cassagnau, Anne Chauty-Frondas, Helene Aubert, Sébastien Barbarot
Journal: JAMA Dermatology (2015)

Congenital hemangiomas (CHs) are rare benign vascular tumors that differ from common infantile hemangiomas in that they grow in utero and are fully developed at birth. While ulceration is a common, predominantly benign complication in infantile hemangioma, little is known about the prognosis of ulcerated CH. However, it has been observed that ulcerated CH may be complicated by life-threatening bleeding episodes.We report 2 cases of ulcerated rapidly involuting congenital hemangiomas (RICH) that were complicated by life-threatening bleeding episodes in the neonatal period. In both cases, the CHs were fed by high-flow vessels and the ensuing massive bleeding was due to superficial vessel wall erosion induced by the ulceration. Both patients were successfully treated with intravascular embolization; one patient underwent additional hemostatic surgery.These 2 cases highlight the importance of closely monitoring children with ulcerated CH because of the risk of severe bleeding. Embolization is the treatment of choice in the case of severe bleeding, as the natural history of RICH is to spontaneously regress.
Large-scale analysis of chromosomal aberrations in cancer karyotypes reveals two distinct paths to aneuploidy
Authors: Michal Ozery-Flato, Chaim Linhart, Luba Trakhtenbrot, Shai Izraeli, Ron Shamir
Journal: Genome biology (2011)

Abstract Background Chromosomal aneuploidy, that is to say the gain or loss of chromosomes, is the most common abnormality in cancer. While certain aberrations, most commonly translocations, are known to be strongly associated with specific cancers and contribute to their formation, most aberrations appear to be non-specific and arbitrary, and do not have a clear effect. The understanding of chromosomal aneuploidy and its role in tumorigenesis is a fundamental open problem in cancer biology. Results We report on a systematic study of the characteristics of chromosomal aberrations in cancers, using over 15,000 karyotypes and 62 cancer classes in the Mitelman Database. Remarkably, we discovered a very high co-occurrence rate of chromosome gains with other chromosome gains, and of losses with losses. Gains and losses rarely show significant co-occurrence. This finding was consistent across cancer classes and was confirmed on an independent comparative genomic hybridization dataset of cancer samples. The results of our analysis are available for further investigation via an accompanying website. Conclusions The broad generality and the intricate characteristics of the dichotomy of aneuploidy, ranging across numerous tumor classes, are revealed here rigorously for the first time using statistical analyses of large-scale datasets. Our finding suggests that aneuploid cancer cells may use extra chromosome gain or loss events to restore a balance in their altered protein ratios, needed for maintaining their cellular fitness.
Values for function in rheumatoid arthritis: patients, professionals, and public
Authors: S Hewlett
Journal: Annals of the Rheumatic Diseases (2001)

Although many disability questionnaires measure fact very efficiently, they do not allow for consideration of the relevance of that disability to the patient. Data suggest that professionals misinterpret the relevance of disability for the patient and thus, also, the outcome of treatment.Firstly, to examine agreement on levels of importance for the items on a validated disability scale (Health Assessment Questionnaire (HAQ) and Modified HAQ (MHAQ)), within groups of patients with rheumatoid arthritis, health professionals, and controls. Secondly, to see if functional items important to patients are included in the HAQ, and whether the HAQ items are important to patients.25 patients with RA, 25 rheumatology health professionals, and 25 healthy controls were asked to rate the importance of the HAQ (20 items) and MHAQ (eight domains). Before seeing the HAQ, patients were asked to generate items of function important to them.Only a slight-fair agreement within each group was found for the level of importance of the HAQ and MHAQ, and also within any combination of the groups (kappa values <0.38). Most of the functional items valued by patients were contained on the HAQ (70%), and no HAQ items were consistently rated as unimportant.Patients, professionals, and healthy controls do not agree on the importance of disabilities. These data support the need to assess the personal impact of disability, as well as disability itself. Individual importance of disability weighted by level of disability is proposed as a model for calculating the personal impact of disability. A new tool to assess the personal impact of disability is being developed.
Splanchnic Extraction and Interconversion of Testosterone and Androstenedione in Man*
Authors: Marco A. Rivarola, Robert T. Singleton, Claude J. Migeon
Journal: Journal of Clinical Investigation (1967)

A constant infusion of (3)H-testosterone and (14)C-androstenedione was administered to four human subjects, two males and two females, until the concentrations of radioactive testosterone and androstenedione in systemic plasma became constant. At that time the concentrations of radioactive testosterone and androstenedione in hepatic vein plasma were determined. Splanchnic extraction of testosterone and androstenedione and the contribution of the splanchnic system to the blood interconversion of testosterone and androstenedione were calculated. Androstenedione is extracted by the splanchnic system more efficiently than testosterone since 82.3% of androstenedione and 44% of testosterone were removed from the plasma after one passage. The fraction of testosterone entering the splanchnic system that is transferred to blood androstenedione was 0.011 and the maximum possible transfer due to recirculation was 0.026. This was 28% of the total blood transfer from testosterone to androstenedione. The fraction of androstenedione entering the splanchnic system that is transferred to blood testosterone after one passage was 0.005, whereas the maximum possible transfer in this system was 0.006. This represented only 16% of the total transfer from androstenedione to testosterone. Therefore, a large fraction of the interconversion of testosterone and androstenedione in vivo occurs outside the splanchnic system.
Evaluation of left ventricular segmental wall motion in hypertrophic cardiomyopathy with myocardial tagging.
Authors: S E Maier, S E Fischer, G C McKinnon, O M Hess, H P Krayenbuehl, P Boesiger
Journal: Circulation (1992)

BACKGROUND Segmental wall motion was assessed noninvasively in eight patients with hypertrophic cardiomyopathy and six healthy volunteers by magnetic resonance myocardial tagging. METHODS AND RESULTS Localization scans were performed for determination of the true short-axis views of the left ventricle (double-angulated view). Spatial modulation of magnetization was used to produce a rectangular grid of landmarks. Distortion of the grid was assessed at end diastole, mid systole, and end systole with multiphase gradient echoes. Image sets were acquired at three different planes, namely, the base, the equator, and the apex. Quantitative evaluation was carried out by computer-assisted image analysis. Each individual grid crossing point was identified automatically and the displacement calculated. A polar coordinate system with the center of gravity as motion reference point was chosen to assess fractional rotation and radial displacement at the endocardial, midwall, and epicardial layers of the septal, anterior, posterior, and inferior regions. A wringing motion of the left ventricle with a clockwise rotation of 5.0 +/- 2.4 degrees at the base and a counterclockwise rotation of -9.6 +/- 2.9 degrees at the apex was observed in control subjects. An equal rotation of 5.0 +/- 2.5 degrees at the base and a slightly reduced rotation of -7.3 +/- 5.2 degrees at the apex was found in patients with hypertrophic cardiomyopathy. A transmural gradient in fractional rotation and radial displacement was observed, with the highest values in the endocardial layer. Rotation in patients with hypertrophic cardiomyopathy was significantly less than in normal volunteers in the posterior region of the equatorial and apical planes. Furthermore, radial displacement was significantly reduced in the septum and inferior wall. In the anterior and posterior wall segments, a reduction of the radial displacement was observed only in the epicardium and midwall layers. CONCLUSIONS Magnetic resonance myocardial tagging allows the noninvasive assessment of regional wall motion. Both in normal volunteers and in patients with hypertrophic cardiomyopathies, cardiac motion occurs in a complex mode, with the base and the apex rotating in opposite directions and the equatorial plane as a transitional zone (wringing motion). A reduced cardiac rotation can be observed in patients with hypertrophic cardiomyopathy mainly in the posterior region, whereas a reduced radial displacement is found in the inferior septal zone.
Outcome After Implantation of a Cardioverter-Defibrillator in Patients With Brugada Syndrome
Authors: Frédéric Sacher, Vincent Probst, Philippe Maury, Dominique Babuty, Jacques Mansourati, Yuki Komatsu, Christelle Marquie, Antonio Rosa, Abou Diallo, Romain Cassagneau, Claire Loizeau, Raphael Martins, Michael E. Field, Nicolas Derval, Shinsuke Miyazaki, Arnaud Denis, Akihiko Nogami, Philippe Ritter, Jean-Baptiste Gourraud, Sylvain Ploux, Anne Rollin, Adlane Zemmoura, Dominique Lamaison, Pierre Bordachar, Bertrand Pierre, Pierre Jaïs, Jean-Luc Pasquié, Mélèze Hocini, François Legal, Pascal Defaye, Serge Boveda, Yoshito Iesaka, Philippe Mabo, Michel Haïssaguerre
Journal: Circulation (2013)

Implantable cardioverter-defibrillator indications in Brugada syndrome remain controversial, especially in asymptomatic patients. Previous outcome data are limited by relatively small numbers of patients or short follow-up durations. We report the outcome of patients with Brugada syndrome implanted with an implantable cardioverter-defibrillator in a large multicenter registry.A total of 378 patients (310 male; age, 46±13 years) with a type 1 Brugada ECG pattern implanted with an implantable cardioverter-defibrillator (31 for aborted sudden cardiac arrest, 181 for syncope, and 166 asymptomatic) were included. Fifteen patients (4%) were lost to follow-up. During a mean follow-up of 77±42 months, 7 patients (2%) died (1 as a result of an inappropriate shock), and 46 patients (12%) had appropriate device therapy (5±5 shocks per patient). Appropriate device therapy rates at 10 years were 48% for patients whose implantable cardioverter-defibrillator indication was aborted sudden cardiac arrest, 19% for those whose indication was syncope, and 12% for the patients who were asymptomatic at implantation. At 10 years, rates of inappropriate shock and lead failure were 37% and 29%, respectively. Inappropriate shock occurred in 91 patients (24%; 4±4 shocks per patient) because of lead failure (n=38), supraventricular tachycardia (n=20), T-wave oversensing (n=14), or sinus tachycardia (n=12). Importantly, introduction of remote monitoring, programming a high single ventricular fibrillation zone (>210-220 bpm), and a long detection time were associated with a reduced risk of inappropriate shock.Appropriate therapies are more prevalent in symptomatic Brugada syndrome patients but are not insignificant in asymptomatic patients (1%/y). Optimal implantable cardioverter-defibrillator programming and follow-up dramatically reduce inappropriate shock. However, lead failure remains a major problem in this population.