tbuckley/cabot-search huggingface dataset:
Supplementary oxygen therapy in COPD: is it really useful?
Authors: P M A CALVERLEY
Journal: Thorax (2000)

Many patients with severe chronic obstructive pulmonary disease (COPD) develop hypoxaemia at rest when awake as their disease progresses. This may or may not be accompanied by hypercapnia but is a poor prognostic feature, independent of the forced expiratory volume in one second (FEV1).1 For many years the scientific study of COPD was driven by the need to gain a greater understanding of the processes which led to these disorders of gas exchange. Ultimately this led to the introduction of effective treatment designed to increase the arterial oxygen tension beyond 8.0 kPa for at least 15 hours per day. The well known randomised controlled trials which confirmed the survival benefit of this treatment2 3 are also the cornerstone of evidence based oxygen prescribing.4 Since these results were published in the 1980s the costs of oxygen therapy have increased steadily in the UK and elsewhere5 and constitute one of the largest medical expenses, particularly in the care of patients with COPD. Over half of this money is spent on providing oxygen for indications other than continuous domiciliary care. The rationale for these other indications is less secure and certainly less studied. The publication of two papers addressing different aspects of this treatment in this issue of Thorax is a welcome addition to our information about this common therapeutic problem.6 7 

The physiological basis of exercise limitation in COPD has been challenged in recent years with the observation that end expiratory lung volume rises during exercise and is closely related to the degree of breathlessness.8 9 Empirical studies have shown that supplementary oxygen increases the six minute walking distance compared with placebo in COPD,10 11 and that these effects are most marked when tests of endurance rather than maximum exercise are conducted.12 More …
Challenges in Prevention of Abusive Head Trauma
Authors: Joanne N. Wood
Journal: JAMA Pediatrics (2015)

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 Pediatrics HomeNew OnlineCurrent IssueFor Authors Podcast 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) 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 Pediatrics journal
Potassium and calcium current blocking properties of the novel antiarrhythmic agent H 345/52: implications for proarrhythmic potential
Authors: Gregory J Amos, Christina Abrahamsson, Göran Duker, Luc Hondeghem, Mattias Palmer, Leif Carlsson
Journal: Cardiovascular Research (2001)

Objectives: To study the blocking effects of H 345/52 on ionic currents of rabbit ventricular myocytes and how these features translate into a proarrhythmic potential. Methods: The single electrode voltage clamp technique was used to study the effects of H 345/52 on the rapid component of the delayed rectifying potassium current, IKr, and the L-type calcium current (ICa). Differential effects of H 345/52 and almokalant on APD prolongation were studied in a rabbit Purkinje fibre/ventricular muscle preparation. The temporal variability of the action potential duration (APD) and its relation to proarrhythmias was examined in Langendorff-perfused rabbit hearts administered H 345/52 or almokalant. Anaesthetised, methoxamine-sensitised rabbits were used to assess the propensity of intravenous H 345/52 and ibutilide to induce torsades de pointes (TdP). Results: H 345/52 potently blocked IKr (IC50=40 nM) without consequential use-dependency. The ICa was also blocked, but at higher concentrations (IC50=1.3 μM). Block of ICa was markedly frequency-dependent (positive) and influenced by membrane potential, such that H 345/52 was more effective following clamp steps from plateau potentials than from −80 mV. In the Purkinje fibre–ventricular muscle preparation, almokalant prolonged the Purkinje fibre APD preferentially, whereas H 345/52 homogeneously prolonged APD in both tissue types. In the perfused rabbit heart, H 345/52 (1 μM) and almokalant (0.3 μM) prolonged APD to a similar degree but increased the temporal variability of APD differently, from 3±0.4 ms in control hearts to 8±1.2 ms and to 38±7.5 ms (P<0.001 vs. H 345/52), respectively. Unequivocal early after-depolarisations were seen in 5/6 almokalant-perfused hearts but in no heart administered H 345/52 (P<0.05). In anaesthetised rabbits, H 345/52 (17.4 μmol/kg) or ibutilide (2.6 μmol/kg maximum), maximally lengthened the QT interval from 133±4.5 to 177±8.0 ms and from 125±5.1 to 166±9.3 ms (P<0.001, n = 8). However, whereas ibutilide induced TdP in all animals at 0.06±0.009 μmol/kg, H 345/52 did not induce TdP (P = 0.0002) at up to 17.4 μmol/kg. Conclusions: H 345/52 blocks IKr with high potency and ICa with somewhat lower potency and was found to delay ventricular repolarisation without substantially increasing temporal or spatial dispersion and without inducing early after-depolarisations or TdP.
The New Zealand Rugby Injury and Performance Project: II. Previous injury experience of a rugby-playing cohort.
Authors: D F Gerrard, A E Waller, Y N Bird
Journal: British Journal of Sports Medicine (1994)

The Rugby Injury and Performance Project (RIPP) is a prospective cohort study by a multidisciplinary research group. Rugby injuries constitute an important area for research because rugby union is New Zealand's national sport and because of the considerable cost of all sports injury acknowledged by the Accident Rehabilitation and Compensation Insurance Corporation (ACC). The initial phase of data collection in the RIPP involved a pre-season questionnaire which, among other things, sought to establish variables relating to the past injury experience of players. The influence of previous injury, the use of safety equipment and the availability and significance of medical advice were among the variables identified by individual questionnaires. This paper analyses the responses to pre-season questions about injury experience in the previous 12 months. In so doing, it identifies baseline data which will be used to address a possible relationship between past injury experience and the prediction of injury during the season.
Putting reasoning and judgement in their proper argumentative place
Authors: Mike Oaksford
Journal: Behavioral and Brain Sciences (2011)

Abstract This commentary agrees with Mercier and Sperber's (M&amp;S's) thesis on the argumentative function of reasoning but suggests that an account of argument strength is required. A Bayesian account of argument strength (Hahn &amp; Oaksford 2007) shows how the deployment of deductive fallacies, weak inductive arguments, and judgment fallacies such as base-rate neglect, can all be rationally defended in the right argumentative context.
Determination of Tissue O2 Tensions by Hollow Visceral Tonometers: Effect of Breathing Enriched O2 Mixtures*
Authors: Edward H. Bergofsky
Journal: Journal of Clinical Investigation (1964)

possible to obtain corresponding samples of ve- nous blood draining the organ to compare tissue and blood gas tensions under various experimental conditions. MethodsTwenty adult mongrel dogs were used in these ex- periments; of these, 15 females were chosen, since it
Bach1 Represses Wnt/β-Catenin Signaling and Angiogenesis
Authors: Li Jiang, Meng Yin, Xiangxiang Wei, Junxu Liu, Xinhong Wang, Cong Niu, Xueling Kang, Jie Xu, Zhongwei Zhou, Shaoyang Sun, Xu Wang, Xiaojun Zheng, Shengzhong Duan, Kang Yao, Ruizhe Qian, Ning Sun, Alex Chen, Rui Wang, Jianyi Zhang, Sifeng Chen, Dan Meng
Journal: Circulation Research (2015)

Wnt/β-catenin signaling has an important role in the angiogenic activity of endothelial cells (ECs). Bach1 is a transcription factor and is expressed in ECs, but whether Bach1 regulates angiogenesis is unknown. This study evaluated the role of Bach1 in angiogenesis and Wnt/β-catenin signaling. Hind-limb ischemia was surgically induced in Bach1(-/-) mice and their wild-type littermates and in C57BL/6J mice treated with adenoviruses coding for Bach1 or GFP. Lack of Bach1 expression was associated with significant increases in perfusion and vascular density and in the expression of proangiogenic cytokines in the ischemic hindlimb of mice, with enhancement of the angiogenic activity of ECs (eg, tube formation, migration, and proliferation). Bach1 overexpression impaired angiogenesis in mice with hind-limb ischemia and inhibited Wnt3a-stimulated angiogenic response and the expression of Wnt/β-catenin target genes, such as interleukin-8 and vascular endothelial growth factor, in human umbilical vein ECs. Interleukin-8 and vascular endothelial growth factor were responsible for the antiangiogenic response of Bach1. Immunoprecipitation and GST pull-down assessments indicated that Bach1 binds directly to TCF4 and reduces the interaction of β-catenin with TCF4. Bach1 overexpression reduces the interaction between p300/CBP and β-catenin, as well as β-catenin acetylation, and chromatin immunoprecipitation experiments confirmed that Bach1 occupies the TCF4-binding site of the interleukin-8 promoter and recruits histone deacetylase 1 to the interleukin-8 promoter in human umbilical vein ECs. Bach1 suppresses angiogenesis after ischemic injury and impairs Wnt/β-catenin signaling by disrupting the interaction between β-catenin and TCF4 and by recruiting histone deacetylase 1 to the promoter of TCF4-targeted genes.
Infliximab for peristomal pyoderma gangrenosum
Authors: D. Mimouni, G.J. Anhalt, D.J. Kouba, H.C. Nousari
Journal: British Journal of Dermatology (2003)

Summary Peristomal pyoderma gangrenosum (PPG) is a variant of pyoderma gangrenosum (PG) that is more refractory to treatment. It is a cause of severe morbidity and poses a therapeutic challenge for the clinician. Infliximab (Remicade®; Centocor, Malvern, PA, USA) is a chimeric monoclonal antibody directed against tumour necrosis factor‐α that has been proven to be effective in the treatment of inflammatory bowel disease (IBD) and rheumatoid arthritis. Currently, very few reports exist documenting its use in the treatment of PG and none in the treatment of PPG. We describe our experience of treating three patients with IBD‐associated PPG with infliximab. All patients tolerated the drug without significant side‐effects. Two patients with PPG recovered completely following the administration of infliximab, and one patient had a partial response to the drug. We conclude that infliximab appears to be a safe and effective therapeutic alternative in patients with PPG.
A point mutation in the cysteine-rich domain of glycoprotein (GP) IIIa results in the expression of a GPIIb-IIIa (αIIbβ3) integrin receptor locked in a high-affinity state and a Glanzmann thrombasthenia–like phenotype
Authors: Catherine Ruiz, Chao-Yan Liu, Qi-Hong Sun, Marianne Sigaud-Fiks, Edith Fressinaud, Jean-Yves Muller, Paquita Nurden, Alan T. Nurden, Peter J. Newman, Nathalie Valentin
Journal: Blood (2001)
Release of cartilage and bone macromolecules into synovial fluid: differences between psoriatic arthritis and rheumatoid arthritis
Authors: B Mansson
Journal: Annals of the Rheumatic Diseases (2001)

<h3>OBJECTIVE</h3> To elucidate whether differences in the destructive tissue process in cartilage and bone in psoriatic arthritis (PsA) and rheumatoid arthritis (RA) can be recognised by different release patterns of molecular fragments derived from joint tissue. <h3>METHODS</h3> Aggrecan, cartilage oligomeric matrix protein (COMP), and bone sialoprotein (BSP) were quantified by immunoassays in knee joint synovial fluid samples. These were obtained early in the disease course of patients with PsA and RA. At the time of arthrocentesis radiographs of their knee and hip joints were normal. <h3>RESULTS</h3> At follow up no destruction had developed in the knees and hips of most patients with PsA (n=18), whereas the patients with RA could be separated into one "destructive" group (n=18) and one "non-destructive" group (n=25). Patients with PsA had low synovial fluid aggrecan concentrations (p&lt;0.001 <i>v</i> the RA destructive group) but high COMP concentrations (p&lt;0.01 and p&lt;0.05<i>v</i> destructive and non-destructive RA groups, respectively). Consequently, the aggrecan/COMP ratio was lowest in the PsA group (p&lt;0.001 and p&lt;0.01 <i>v</i> the destructive and non-destructive RA group, respectively). The synovial fluid concentrations of BSP did not differ between the three patient groups. <h3>CONCLUSIONS</h3> The release pattern of aggrecan and COMP, reflecting cartilage turnover, differed between the PsA group and, particularly, the destructive RA group. This suggests that different pathophysiological mechanisms for cartilage involvement operate in these conditions, with different destructive potential. The BSP concentrations did not differ between the patients groups, which indicates similar levels of bone involvement.
Prospective, randomized evaluation of thrombectomy prior to percutaneous intervention in diseased saphenous vein grafts and thrombus-containing coronary arteries
Authors: Gregg W. Stone, David A. Cox, Joseph Babb, Dean Nukta, Luc Bilodeau, Louis Cannon, Thomas D. Stuckey, James Hermiller, Eric A. Cohen, Reginald Low, Steven R. Bailey, Alexandra J. Lansky, Richard E. Kuntz
Journal: Journal of the American College of Cardiology (2003)
Sarcoidosis patient: Do we need to perform plethysmography when spirometry and DLCO were done?
Authors: Piotr Boros, Magdalena Martusewicz-Boros, Philip Quanjer, Paul Enright, Stefan Wesolowski
Journal: European Respiratory Journal (2011)

Introduction: Plethysmographic measurement of total lung capacity (TLCbox) is the gold standard for measuring lung volumes. Gas dilution methods are considered less accurate in patients with substantial airway obstruction and take more time. DLCOsb is usually done in patients suspected of having an interstitial lung disease (ILD) and the test includes measurement of alveolar volume (VA).

Aim of study: To compare TLCbox with TLCVA in a large group of sarcoidosis patients in different stages of the disease.

Methods: Data from 830 consecutive sarcoidosis patients (223 in stage I, 486 in stage II, and 121 in stage III). All tests met 2005 ATS/ERS PFT technique and quality guidelines. TLCVA was calculated as the sum of VA and dead space.

Results: TLCbox was larger than TLCVA by a mean of 0.18 L (95%CI: 0.15; 0.20) and 2.8% (95%CI: 2.3; 3.3). TLC was normal (above the 5th percentile) in 772 patients (93%) by TLCbox and in 762 cases (92%) by TLCVA. Sensitivity of the TLCVA for a low TLCbox was 83% and specificity 97%, so NPV was 99% and PPV 71%. The AUC by ROC analysis was 0.90. Airway obstruction was present in only 12% of the patients, but their TLCVA was significantly lower than their TLCbox when compared to those without airway obstruction (0.39 L ±0.39 vs. 0.15 L ±0.39). In this subgroup, the sensitivity of TLCVA was only 50% and specificity 96%, so NPV was 98% but PPV only 33%. The differences of TLCbox and TLCVA were correlated with FEV1/FVC ratio.

Conclusions: A normal TLCVA rules out a low TLCbox with a high degree of certainty in patients with sarcoidosis, but a low TLCVA does not confirm a low TLCbox in patients with airway obstruction.
Determinants of 24-hour energy expenditure in man. Methods and results using a respiratory chamber.
Authors: E Ravussin, S Lillioja, T E Anderson, L Christin, C Bogardus
Journal: Journal of Clinical Investigation (1986)

Daily human energy requirements calculated from separate components of energy expenditure are inaccurate and usually in poor agreement with measured energy intakes. Measurement of energy expenditure over periods of 24 h or longer is needed to determine more accurately rates of daily energy expenditure in humans. We provide a detailed description of a human respiratory chamber and methods used to determine rates of energy expenditure over 24-h periods in 177 subjects. The results show that: fat-free mass (FFM) as estimated by densitometry is the best available determinant of 24-h energy expenditures (24EE) and explains 81% of the variance observed between individuals (24EE [kcal/d] = 597 + 26.5 FFM); 24EE in an individual is very reproducible (coefficient of variation = 2.4%); and even when adjusted for differences in FFM, there is still considerable interperson variability of the daily energy expenditure. A large portion of the variability of 24EE among individuals, independent of differences in body size, was due to variability in the degree of spontaneous physical activity, i.e., "fidgeting," which accounted for 100-800 kcal/d in these subjects.
Role of moesin in hyaluronan induced cell migration in glioblastoma multiforme
Authors: Leroi V DeSouza, Ajay Matta, Zia Karim, Joydeep Mukherjee, X Simon Wang, Olga Krakovska, Gelareh Zadeh, Abhijit Guha, KW Michael Siu
Journal: Molecular Cancer (2013)

A major barrier to effective treatment of glioblastoma multiforme (GBM) is the invasion of glioma cells into the brain parenchyma rendering local therapies such as surgery and radiation therapy ineffective. GBM patients with such highly invasive and infiltrative tumors have poor prognosis with a median survival time of only about a year. However, the mechanisms leading to increased cell migration, invasion and diffused behavior of glioma cells are still poorly understood.In the current study, we applied quantitative proteomics for the identification of differentially expressed proteins in GBMs as compared to non-malignant brain tissues.Our study led to the identification of 23 proteins showing overexpression in GBM; these include membrane proteins, moesin and CD44. The results were verified using Western blotting and immunohistochemistry in independent set of GBM and non-malignant brain tissues. Both GBM tissues and glioma cell lines (U87 / U373) demonstrated membranous expression of moesin and CD44, as revealed by immunohistochemistry and immunofluorescence, respectively. Notably, glioma cells transfected with moesin siRNA displayed reduced migration and invasion on treatment with hyaluronan (HA), an important component of the extracellular matrix in GBM. CD44, a transmembrane glycoprotein, acts as a major receptor for hyaluronan (HA). Using co-immunoprecipitation assays, we further demonstrated that moesin interacts with CD44 in glioma cells only after treatment with HA; this implicates a novel role of moesin in HA-CD44 signaling in gliomas.Our results suggest that development of inhibitors which interfere with CD44-moesin interactions may open a new avenue in the future to mitigate cellular migration in gliomas.
Comparison of cardiac and pulmonary-specific quality-of-life measures in pulmonary arterial hypertension
Authors: H. Chen, T. De Marco, E.A. Kobashigawa, P.P. Katz, V.W. Chang, P.D. Blanc
Journal: European Respiratory Journal (2011)

Studies systematically comparing the performance of health-related quality-of-life (HRQoL) instruments in pulmonary arterial hypertension (PAH) are lacking. We sought to address this by comparing cardiac and respiratory-specific measures of HRQoL in PAH. We prospectively assessed HRQoL in 128 patients with catheterisation-confirmed PAH at baseline and at 6, 12 and post-24 month follow-up visits. Cardiac-specific HRQoL was assessed using the Minnesota Living with Heart Failure Questionnaire (LHFQ); respiratory-specific HRQoL was assessed using the Airways Questionnaire 20 (AQ20); and general health status was assessed using the 36-item Short Form physical component summary (SF-36 PCS). The LHFQ and AQ20 were highly intercorrelated. Both demonstrated strong internal consistency and converged with the SF-36 PCS. Both discriminated patients based on World Health Organization (WHO) functional class, 6-min walking distance (6MWD) and Borg dyspnoea index (BDI), with the exception of a potential floor effect associated with low 6MWD. The LHFQ was more responsive than the AQ20 to changes over time in WHO functional class, 6MWD and BDI. In multivariate analyses, the LHFQ and AQ20 were each longitudinal predictors of general health status, independent of functional class, 6MWD and BDI. In conclusion, both cardiac-specific and respiratory-specific measures appropriately assess HRQoL in most patients with PAH. Overall, the LHFQ demonstrates stronger performance characteristics than the AQ20.
Epidurual pneumatosis: a benign complication of benign pneumomediastinum
Authors: C Defouilloy, C Galy, E Lobjoie, V Strunski, M Ossart
Journal: European Respiratory Journal (1995)

Subcutaneous emphysema and pneumomediastinum are well-known complications of barotrauma. There are no fascial barriers between the posterior mediastinum and the retropharyngeal and epidural spaces; thus, air can diffuse freely to the epidural space and produce an epidural pneumatosis. We report a case of epidural pneumatosis caused by a pneumomediastinum following nasotracheal intubation for an attempted suicide. This benign complication of air leakage was easily recognized on computed tomography (CT) scan.
Cell Adhesion Regulates CDC25A Expression and Proliferation in Acute Myeloid Leukemia
Authors: Anne Fernandez-Vidal, Loïc Ysebaert, Christine Didier, Remy Betous, Fabienne De Toni, Naïs Prade-Houdellier, Cécile Demur, Marie-Odile Contour-Galcéra, Grégoire P. Prévost, Bernard Ducommun, Bernard Payrastre, Claire Racaud-Sultan, Stéphane Manenti
Journal: Cancer Research (2006)

Abstract The effects of cell adhesion on leukemia cell proliferation remain poorly documented and somehow controversial. In this work, we investigated the effect of adhesion to fibronectin on the proliferation of acute myeloid leukemia (AML) cell lines (U937 and KG1a) and CD34+ normal or leukemic primary cells. We observed an increased rate of proliferation of AML cells when adhered to fibronectin, concomitant with accelerated S-phase entry and accumulation of CDC25A. Conversely, normal CD34+ cell proliferation was decreased by adhesion to fibronectin with a concomitant drop in CDC25A expression. Importantly, we showed that both small interfering RNA (siRNA)–mediated CDC25A down-regulation and a recently developed CDC25 pharmacologic inhibitor impaired this adhesion-dependent proliferation, establishing a functional link between CDC25A accumulation and adhesion-dependent proliferation in leukemic cells. CDC25A accumulation was found only slightly dependent on transcriptional regulation and essentially due to modifications of the proteasomal degradation of the protein as shown using proteasome inhibitors and reverse transcription-PCR. Interestingly, CDC25A regulation was Chk1 dependent in these cells as suggested by siRNA-mediated down-regulation of this protein. Finally, we identified activation of the phosphatidylinositol 3-kinase/Akt pathway as an adhesion-dependent regulation mechanism of CDC25A protein expression. Altogether, our data show that in leukemic cells adhesion to fibronectin increases CDC25A expression through proteasome- and Chk1-dependent mechanisms, resulting in enhanced proliferation. They also suggest that these adhesion-dependent proliferation properties of hematopoietic cells may be modified during leukemogenesis. (Cancer Res 2006; 66(14): 7128-35)