133 research outputs found

    Fetal Doppler changes one week after endoscopic equatorial laser for twin-to-twin transfusion syndrome: a longitudinal study

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    Objective: To investigate sequential Doppler changes in donors and recipients before and 1 week after endoscopic laser for twin\u2010to\u2010twin transfusion syndrome (TTTS) and to examine factors that may be associated with such changes. Methods: In TTTS pregnancies undergoing laser treatment, we examined fetal Doppler changes before and 1 week postintervention. Intrauterine death rates and preoperative factors were analyzed in relation to Doppler changes. Results: Among 129 (85.4%) donors surviving at 1 week after laser, there was normalization of umbilical artery flow in 26 (72.2%) of 36 cases with preoperative abnormal Dopplers. In the remaining 10 (27.8%) fetuses, abnormal findings persisted. The rate of later intrauterine death was significantly higher in the latter group (6 of 10, 60.0%) compared with fetuses in which Doppler findings normalized (4 of 26, 15.4%; P < .05), with no difference in the rate of severe donor growth restriction between the 2 groups (80.0% vs 65.4%, respectively; P = .688). Conclusions: In about 70% of TTTS donors with preoperative abnormal umbilical artery Doppler, there was normalization 1 week after endoscopic laser. The incidence of fetal growth restriction was not significantly different in donors with persistence of Doppler abnormalities compared with those with normalized findings

    The use of sirolimus in the treatment of giant cystic lymphangioma : Four case reports and update of medical therapy

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    Rationale: Lymphatic malformations (LMs) are rare and benign anomalies resulting from the defective embryological development of the primordial lymphatic structures. Due to their permeative growth throughout all tissue layers, treatment is often challenging. Small asymptomatic lesions can be conservatively managed, while symptomatic lesions require active management. Surgery has been historically considered the treatment of choice, but today less invasive therapeutic options are preferred (sclerotherapy, laser therapy, oral medications). However, there are not uniform therapeutic protocols. Sirolimus is an oral medication that has been reported to be effective in the recent literature. Here we present the case of 4 newborns with giant multicystic lymphangioma treated with oral sirolimus after surgical resection had failed. Patient concerns: At birth the LMs were clinically appreciated as giant masses involving different organs and structures. Diagnoses: All patients had a prenatal diagnosis of giant multicystic lymphangioma confirmed at histological and cytological analysis. Interventions: Patients were treated with oral sirolimus after unsuccessful surgical resection. Outcomes: In all patients, sirolimus determined an overall reduction of the mass and a global involution from the macro-to the microcystic composition. Sirolimus was safe and poor disadvantages had been observed. The main and isolated adverse effect at laboratory analysis was progressive dyslipidemia, with increasing levels of total cholesterol and triglycerides. Lessons: To date, our experience with sirolimus in the management of LMs is favorable. We recommend the use of sirolimus after unsuccessful surgical excision have been tried or when the surgical approach is not feasible. A multidisciplinary follow-up is needed to monitor disease evolution

    Comparison of energy flows in deep inelastic scattering events with and without a large rapidity gap

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    Energy flows in deep inelastic electron-proton scattering are investigated at a centre-of-mass energy of 269 GeV for the range Q2 ≥ 10 GeV2 using the ZEUS detector. A comparison is made between events with and without a large rapidity gap between the hadronic system and the proton direction. The energy flows, corrected for detector acceptance and resolution, are shown for these two classes of events in both the HERA laboratory frame and the Breit frame. From the differences in the shapes of these energy flows we conclude that QCD radiation is suppressed in the large-rapidity-gap eents compared to the events without a large rapidity gap. © 1994

    Observation of hard scattering in photoproduction events with a large rapidity gap at HERA

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    Events with a large rapidity gap and total transverse energy greater than 5 GeV have been observed in quasi-real photoproduction at HERA with the ZEUS detector. The distribution of these events as a function of the γp centre of mass energy is consistent with diffractive scattering. For total transverse energies above 12 GeV, the hadronic final states show predominantly a two-jet structure with each jet having a transverse energy greater than 4 GeV. For the two-jet events, little energy flow is found outside the jets. This observation is consistent with the hard scattering of a quasi-real photon with a colourless object in the proton. © 1995

    Start a neonatal extracorporeal membrane oxygenation program: A multistep team training

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    Background: Extracorporeal membrane oxygenation (ECMO) is a complex life-saving support for acute cardio-respiratory failure, unresponsive to medical treatment. Emergency events on ECMO are rare but require immediate and proficient management. Multidisciplinary ECMO team members need to acquire and maintain over time cognitive, technical and behavioral skills, to safely face life-threatening clinical scenarios. Methods: A multistep educational program was delivered in a 4-year period to 32 ECMO team members, based on guidelines from the Extracorporeal Life Support Organization. A first traditional module was provided through didactic lectures, hands-on water drills, and laboratory animal training. The second phase consisted of a multi-edition high-fidelity simulation-based training on a modified neonatal mannequin (SimNewB\uae). In each session, participants were called to face, in small groups, ten critical scenarios, followed by debriefing time. Trainees underwent a pre-test for baseline competency assessment. Once completed the full training program, a post-test was administered. Pre- and post-test scores were compared. Trainees rated the educational program through survey questionnaires. Results: 28 trainees (87.5%) completed the full educational program. ECMO staffskills improved from a median pre-test score of 7.5/18 (IQR = 6-11) to 14/18 (IQR = 14-16) at post-test (P < 0.001, Wilcoxon rank test). All trainees highly rated the educational program and its impact on their practice. They reported high-fidelity simulations to be beneficial to novice learners as it increased self-confidence in ECMO-emergencies (according to 100% of surveyed), theoretical knowledge (61.5%) and team-work/communicative skills (58%). Conclusions: The multistep ECMO team training increased staff' knowledge, technical skills, teamwork, and self-confidence, allowing the successful development of a neonatal respiratory ECMO program. Conventional training was perceived as relevant in the early phase of the program development, while the active learning emerged to be more beneficial to master ECMO knowledge, specific skills, and team performance

    Observation of events with a large rapidity gap in deep inelastic scattering at HERA

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    In deep inelastic, neutral current scattering of electrons and protons at s=296 GeV, we observe in the ZEUS detector events with a large rapidity gap in the hadronic final state. They occur in the region of small Bjorken x and are observed up to Q2 of 100 GeV2. They account for about 5% of the events with Q2≥10 GeV2. Their general properties are inconsistent with the dominant mechanism of deep inelastic scattering, where color is transferred between the scattered quark and the proton remnant, and suggest that the underlying production mechanism is the diffractive dissociation of the virtual photon. © 1993

    Extraction of the gluon density of the proton at x

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    The gluon momentum density xg(x, Q2) of the proton was extracted at Q2 = 20 GeV2 for small values of x between 4 × 10-4 and 10-2 from the scaling violations of the proton structure function F2 measured recently by ZEUS in deep inelastic neutral current ep scattering at HERA. The extraction was performed in two ways. Firstly, using a global NLO fit to the ZEUS data on F2 at low x constrained by measurementsfrom NMC at larger x; and secondly using published approximate methods for the solution of the GLAP QCD evolution equations. Consistent results are obtained. A substantial increase of the gluon density is found at small x in comparison with the NMC result obtained at larger values of x. © 1995

    Initial study of deep inelastic scattering with ZEUS at HERA

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    Results are presented on neutral current, deep inelastic scattering measured in collisions of 26.7 GeV electrons and 820 GeV protons. The events typically populate a range in Q2 from 10 to 100 GeV2. The values of x extend down to x ∼ 10-4 which is two orders of magnitude lower than previously measured at such Q2 values in fixed target experiments. The measured cross sections are in accord with the extrapolations of current parametrisations of parton distributions. © 1993

    Inclusive jet differential cross sections in photoproduction at HERA

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    Inclusive jet differential cross sections for the reaction ep → jet + X at Q2 below 4 GeV2 have been measured with the ZEUS detector at HERA using an integrated luminosity of 0.55 pb-1. These cross sections are given in the kinematic region 0.2 \u3c y \u3c 0.85, for jet pseudorapidities in the ep-laboratory range -1 \u3c ηjet \u3c 2 and refer to jets at the hadron level with a cone radius of one unit in the η - θ plane. These results correspond to quasi-real photoproduction at centre-of-mass energies in the range 130-270 GeV and, approximately, for jet pseudorapidities in the interval -3 \u3c ηjet(λp CMS) \u3c 0. These measurements cover a new kinematic regime of the partonic structure of the photon, at typical scales up to ∼300 GeV2 and photon fractional momenta down to xγ ∼ 10-2. Leading logarithm parton shower Monte Carlo calculations, which include both resolved and direct processes and use the predictions of currently available parametrisations of the photon parton distributions, describe in general the shape and magnitude of the measured ηjet and Etjet distributions. © 1995

    Observation of hard scattering in photoproduction at HERA

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    We report a study of electron proton collisions at very low Q2, corresponding to virtual photoproduction at centre of mass energies in the range 100-295 GeV. The distribution in transverse energy of the observed hadrons is much harder than can be explained by soft processes. Some of the events show back-to-back two-jet production at the rate and with the characteristics expected from hard two-body scattering. A subset of the two-jet events have energy in the electron direction consistent with that expected from the photon remnant in resolved photon processes. © 1992
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