887 research outputs found
Cardiovascular magnetic resonance in patients with pectus excavatum compared with normal controls
<p>Abstract</p> <p>Purpose</p> <p>To assess cardiothoracic structure and function in patients with pectus excavatum compared with control subjects using cardiovascular magnetic resonance imaging (CMR).</p> <p>Method</p> <p>Thirty patients with pectus excavatum deformity (23 men, 7 women, age range: 14-67 years) underwent CMR using 1.5-Tesla scanner (Siemens) and were compared to 25 healthy controls (18 men, 7 women, age range 18-50 years). The CMR protocol included cardiac cine images, pulmonary artery flow quantification, time resolved 3D contrast enhanced MR angiography (CEMRA) and high spatial resolution CEMRA. Chest wall indices including maximum transverse diameter, pectus index (PI), and chest-flatness were measured in all subjects. Left and right ventricular ejection fractions (LVEF, RVEF), ventricular long and short dimensions (LD, SD), mid-ventricle myocardial shortening, pulmonary-systemic circulation time, and pulmonary artery flow were quantified.</p> <p>Results</p> <p>In patients with pectus excavatum, the pectus index was 9.3 ± 5.0 versus 2.8 ± 0.4 in controls (P < 0.001). No significant differences between pectus excavatum patients and controls were found in LV ejection fraction, LV myocardial shortening, pulmonary-systemic circulation time or pulmonary flow indices. In pectus excavatum, resting RV ejection fraction was reduced (53.9 ± 9.6 versus 60.5 ± 9.5; P = 0.013), RVSD was reduced (P < 0.05) both at end diastole and systole, RVLD was increased at end diastole (P < 0.05) reflecting geometric distortion of the RV due to sternal compression.</p> <p>Conclusion</p> <p>Depression of the sternum in pectus excavatum patients distorts RV geometry. Resting RVEF was reduced by 6% of the control value, suggesting that these geometrical changes may influence myocardial performance. Resting LV function, pulmonary circulation times and pulmonary vascular anatomy and perfusion indices were no different to controls.</p
First-line treatment with oxaliplatin and capecitabine in patients with advanced or metastatic oesophageal cancer: a phase II study
This phase II study assessed the safety and efficacy of oxaliplatin and capecitabine in patients with advanced oesophageal cancer. Fifty-one eligible patients received oxaliplatin 130âmgâmâ2 intravenously on day 1 and capecitabine 1000âmgâmâ2 orally twice daily on days 1 to 14 in a 21-day treatment cycle as first-line treatment for advanced oesophageal cancer. Grade 3 neutropenia was seen in one patient and anaemia in another patient. No grade 4 haematological toxicities were observed. Grade 4 non-haematological toxicity (lethargy) occurred in one patient (2%). Grade 3 non-haematological toxicity was seen in 14 (27%) patients (vomiting and polyneuropathy (8%); nausea (6%); lethargy and handâfoot syndrome (4%); and anorexia, diarrhoea, and hyperbilirubinaemia (each in one patient)). In 22% of the patients, toxicity was the reason for stopping the treatment. The overall response rate was 39%. The median overall survival was 8 months; the 1-year survival rate was 26%. In the quality of life (QoL) analysis, the emotional well-being improved during treatment, but the physical functioning scores declined. The fatigue score on the symptom scales increased. Overall, the global QoL score did not change during treatment. In conclusion, the activity of oxaliplatin and capecitabine is comparable with other chemotherapy regimens in advanced oesophageal cancer with a low frequency of grade 3/4 toxicity. Because this treatment can be given on an outpatient basis, it is probably less toxic than cisplatin-based therapy and preserves QoL during treatment, it is a viable treatment option in patients with advanced oesophageal cancer
Remote Ischemic Conditioning as an Additional Treatment for Acute Ischemic Stroke.
Acute ischemic stroke (AIS) is the leading cause of disability in adults worldwide and has the second highest mortality of all cardiovascular diseases[1]. The burden of stroke is likely to increase significantly during the next decades, primarily due to population growth and aging[2]. Given the detrimental impact of stroke on healthcare (costs) and patient well-being, it is imperative to explore opportunities for novel therapies to add to the current treatment to further minimize neurological injury.
During an ischemic stroke, occlusion of a cerebral artery abrogates cerebral perfusion, causing brain tissue distal from the occlusion to become deprived of oxygen and nutrients, ultimately leading to ischemic injury. Surrounding the ischemic core an area called the penumbra contains potentially reversible injured brain tissue, which may remain viable for several hours. Whilst the time window to attenuate the detrimental impact of an ischemic stroke seems limited to six hours after onset of AIS[3, 4], recent research suggests that subgroups may benefit up to 24 hours[5, 6]. This time window of 6-24 hours offers perspective for hospital-based, additional therapies to reduce ischemic injury and minimize clinical deterioration in AIS patients.
This review focuses on remote ischemic conditioning (RIC) as an additive therapy to improve clinical outcomes in AIS patients, both when applied as a single as well as repeated bouts. RIC refers to the application of several cycles of brief ischemia and reperfusion to a limb (using a blood pressure cuff). Pre-clinical work revealed this stimulus to reduce neural damage after reperfusion[7-11], validating the concept that RIC may have clinical potential in AIS. RIC therefore represents a simple, low cost therapeutic strategy that may salvage brain tissue in the penumbral area. In this review, we will summarize (pre)clinical evidence for the efficacy of RIC as an additional therapy in AIS patients
Lung Function after the Minimal Invasive Pectus Excavatum Repair (Nuss Procedure)
Background The Nuss procedure was introduced at our center in 1999. The operation was mainly performed for cosmesis. Little information is available regarding the influence of this operation on lung function. Methods The aim of this study, a prospective analysis, was to analyze the effect of the Nuss procedure on lung function variables. Between 1999 and 2007 a total of 203 patients with pectus excavatum were treated with the Nuss procedure, of whom 145 (104 male, 41 female) were located at Emma Childrenâs Hospital. In the latter subset of consecutive patients, static lung function variables [total lung capacity (TLC), functional residual capacity (FRC), vital capacity (VC)] and dynamic lung function variables [forced expired volume in 1 s (FEV1), maximum expiratory flow (MEF50)] were performed using spirometry and body box measurements at four time points: prior to operation Some of these data were presented at the International Surgical Week
In vitro inhibition of monkeypox virus production and spread by Interferon-ÎČ
<p>Abstract</p> <p>Background</p> <p>The <it>Orthopoxvirus </it>genus contains numerous virus species that are capable of causing disease in humans, including variola virus (the etiological agent of smallpox), monkeypox virus, cowpox virus, and vaccinia virus (the prototypical member of the genus). Monkeypox is a zoonotic disease that is endemic in the Democratic Republic of the Congo and is characterized by systemic lesion development and prominent lymphadenopathy. Like variola virus, monkeypox virus is a high priority pathogen for therapeutic development due to its potential to cause serious disease with significant health impacts after zoonotic, accidental, or deliberate introduction into a naĂŻve population.</p> <p>Results</p> <p>The purpose of this study was to investigate the prophylactic and therapeutic potential of interferon-ÎČ (IFN-ÎČ) for use against monkeypox virus. We found that treatment with human IFN-ÎČ results in a significant decrease in monkeypox virus production and spread <it>in vitro</it>. IFN-ÎČ substantially inhibited monkeypox virus when introduced 6-8 h post infection, revealing its potential for use as a therapeutic. IFN-ÎČ induced the expression of the antiviral protein MxA in infected cells, and constitutive expression of MxA was shown to inhibit monkeypox virus infection.</p> <p>Conclusions</p> <p>Our results demonstrate the successful inhibition of monkeypox virus using human IFN-ÎČ and suggest that IFN-ÎČ could potentially serve as a novel safe therapeutic for human monkeypox disease.</p
Surface pretreatments for medical application of adhesion
Medical implants and prostheses (artificial hips, tendono- and ligament plasties) usually are multi-component systems that may be machined from one of three material classes: metals, plastics and ceramics. Typically, the body-sided bonding element is bone. The purpose of this contribution is to describe developments carried out to optimize the techniques , connecting prosthesis to bone, to be joined by an adhesive bone cement at their interface. Although bonding of organic polymers to inorganic or organic surfaces and to bone has a long history, there remains a serious obstacle in realizing long-term high-bonding strengths in the in vivo body environment of ever present high humidity. Therefore, different pretreatments, individually adapted to the actual combination of materials, are needed to assure long term adhesive strength and stability against hydrolysis. This pretreatment for metal alloys may be silica layering; for PE-plastics, a specific plasma activation; and for bone, amphiphilic layering systems such that the hydrophilic properties of bone become better adapted to the hydrophobic properties of the bone cement. Amphiphilic layering systems are related to those developed in dentistry for dentine bonding. Specific pretreatment can significantly increase bond strengths, particularly after long term immersion in water under conditions similar to those in the human body. The bond strength between bone and plastic for example can be increased by a factor approaching 50 (pealing work increasing from 30 N/m to 1500 N/m). This review article summarizes the multi-disciplined subject of adhesion and adhesives, considering the technology involved in the formation and mechanical performance of adhesives joints inside the human body
A phase II study of capecitabine and docetaxel combination chemotherapy in patients with advanced gastric cancer
Jet energy measurement with the ATLAS detector in proton-proton collisions at root s=7 TeV
The jet energy scale and its systematic uncertainty are determined for jets measured with the ATLAS detector at the LHC in proton-proton collision data at a centre-of-mass energy of âs = 7TeV corresponding to an integrated luminosity of 38 pb-1. Jets are reconstructed with the anti-kt algorithm with distance parameters R=0. 4 or R=0. 6. Jet energy and angle corrections are determined from Monte Carlo simulations to calibrate jets with transverse momenta pTâ„20 GeV and pseudorapidities {pipe}η{pipe}<4. 5. The jet energy systematic uncertainty is estimated using the single isolated hadron response measured in situ and in test-beams, exploiting the transverse momentum balance between central and forward jets in events with dijet topologies and studying systematic variations in Monte Carlo simulations. The jet energy uncertainty is less than 2. 5 % in the central calorimeter region ({pipe}η{pipe}<0. 8) for jets with 60â€pT<800 GeV, and is maximally 14 % for pT<30 GeV in the most forward region 3. 2â€{pipe}η{pipe}<4. 5. The jet energy is validated for jet transverse momenta up to 1 TeV to the level of a few percent using several in situ techniques by comparing a well-known reference such as the recoiling photon pT, the sum of the transverse momenta of tracks associated to the jet, or a system of low-pT jets recoiling against a high-pT jet. More sophisticated jet calibration schemes are presented based on calorimeter cell energy density weighting or hadronic properties of jets, aiming for an improved jet energy resolution and a reduced flavour dependence of the jet response. The systematic uncertainty of the jet energy determined from a combination of in situ techniques is consistent with the one derived from single hadron response measurements over a wide kinematic range. The nominal corrections and uncertainties are derived for isolated jets in an inclusive sample of high-pT jets. Special cases such as event topologies with close-by jets, or selections of samples with an enhanced content of jets originating from light quarks, heavy quarks or gluons are also discussed and the corresponding uncertainties are determined. © 2013 CERN for the benefit of the ATLAS collaboration
Measurement of the inclusive and dijet cross-sections of b-jets in pp collisions at sqrt(s) = 7 TeV with the ATLAS detector
The inclusive and dijet production cross-sections have been measured for jets
containing b-hadrons (b-jets) in proton-proton collisions at a centre-of-mass
energy of sqrt(s) = 7 TeV, using the ATLAS detector at the LHC. The
measurements use data corresponding to an integrated luminosity of 34 pb^-1.
The b-jets are identified using either a lifetime-based method, where secondary
decay vertices of b-hadrons in jets are reconstructed using information from
the tracking detectors, or a muon-based method where the presence of a muon is
used to identify semileptonic decays of b-hadrons inside jets. The inclusive
b-jet cross-section is measured as a function of transverse momentum in the
range 20 < pT < 400 GeV and rapidity in the range |y| < 2.1. The bbbar-dijet
cross-section is measured as a function of the dijet invariant mass in the
range 110 < m_jj < 760 GeV, the azimuthal angle difference between the two jets
and the angular variable chi in two dijet mass regions. The results are
compared with next-to-leading-order QCD predictions. Good agreement is observed
between the measured cross-sections and the predictions obtained using POWHEG +
Pythia. MC@NLO + Herwig shows good agreement with the measured bbbar-dijet
cross-section. However, it does not reproduce the measured inclusive
cross-section well, particularly for central b-jets with large transverse
momenta.Comment: 10 pages plus author list (21 pages total), 8 figures, 1 table, final
version published in European Physical Journal
Effective Rheology of Bubbles Moving in a Capillary Tube
We calculate the average volumetric flux versus pressure drop of bubbles
moving in a single capillary tube with varying diameter, finding a square-root
relation from mapping the flow equations onto that of a driven overdamped
pendulum. The calculation is based on a derivation of the equation of motion of
a bubble train from considering the capillary forces and the entropy production
associated with the viscous flow. We also calculate the configurational
probability of the positions of the bubbles.Comment: 4 pages, 1 figur
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