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1.
Scott Med J ; 67(4): 189-195, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35818757

RESUMEN

BACKGROUND AND AIMS: Bystanders should be protected against aerosols, droplets, saliva, blood and vomitus during resuscitation after cardiac arrest The SARUS (safer - airway - resuscitation) CPR airway hood™ is a clear plastic cover and integrated mask that envelopes the head and torso. Our objectives were to test leakage using saline aerosol generation tests, then assess the performance of the hood during mock cardio-pulmonary resuscitation on a manikin. METHODS: A checklist was validated by comparing the performance of 10 novices against 10 experts during mock resuscitation. Thereafter, 15 novices were tested with and without the hood, in a randomised cross-over study, one week apart. RESULTS: Laboratory analysis showed a > 99% reduction of saline particles detected 5 cm, 75 cm and 165 cm above volunteers wearing the hood. On manikins, experts scored better compared to novices, 8.5 (0.7) vs 7.6 (1.2), difference (95%CI) 0.9 (0.4-1.3), P = 0.0004. Novice performance was equivalent using the hood and standard equipment, 7.3 (1.4) vs 7.3 (1.1) respectively, difference (90%CI) 0.0 (-0.3 - 0.3), P = 0.90. CONCLUSION: Aerosol transmission reduced in the breathing zone. Simulated resuscitation by novices was equivalent with and without the hood.


Asunto(s)
Reanimación Cardiopulmonar , Paro Cardíaco , Humanos , Estudios Cruzados , Maniquíes , Aerosoles
2.
BMC Plant Biol ; 21(1): 590, 2021 Dec 13.
Artículo en Inglés | MEDLINE | ID: mdl-34903166

RESUMEN

BACKGROUND: Arabinogalactan-proteins (AGPs) are structurally complex hydroxyproline-rich cell wall glycoproteins ubiquitous in the plant kingdom. AGPs biosynthesis involves a series of post-translational modifications including the addition of type II arabinogalactans to non-contiguous Hyp residues. To date, eight Hyp-galactosyltransferases (Hyp-GALTs; GALT2-GALT9) belonging to CAZy GT31, are known to catalyze the addition of the first galactose residues to AGP protein backbones and enable subsequent AGP glycosylation. The extent of genetic redundancy, however, remains to be elucidated for the Hyp-GALT gene family. RESULTS: To examine their gene redundancy and functions, we generated various multiple gene knock-outs, including a triple mutant (galt5 galt8 galt9), two quadruple mutants (galt2 galt5 galt7 galt8, galt2 galt5 galt7 galt9), and one quintuple mutant (galt2 galt5 galt7 galt8 galt9), and comprehensively examined their biochemical and physiological phenotypes. The key findings include: AGP precipitations with ß-Yariv reagent showed that GALT2, GALT5, GALT7, GALT8 and GALT9 act redundantly with respect to AGP glycosylation in cauline and rosette leaves, while the activity of GALT7, GALT8 and GALT9 dominate in the stem, silique and flowers. Monosaccharide composition analysis showed that galactose was decreased in the silique and root AGPs of the Hyp-GALT mutants. TEM analysis of 25789 quintuple mutant stems indicated cell wall defects coincident with the observed developmental and growth impairment in these Hyp-GALT mutants. Correlated with expression patterns, galt2, galt5, galt7, galt8, and galt9 display equal additive effects on insensitivity to ß-Yariv-induced growth inhibition, silique length, plant height, and pollen viability. Interestingly, galt7, galt8, and galt9 contributed more to primary root growth and root tip swelling under salt stress, whereas galt2 and galt5 played more important roles in seed morphology, germination defects and seed set. Pollen defects likely contributed to the reduced seed set in these mutants. CONCLUSION: Additive and pleiotropic effects of GALT2, GALT5, GALT7, GALT8 and GALT9 on vegetative and reproductive growth phenotypes were teased apart via generation of different combinations of Hyp-GALT knock-out mutants. Taken together, the generation of higher order Hyp-GALT mutants demonstrate the functional importance of AG polysaccharides decorating the AGPs with respect to various aspects of plant growth and development.


Asunto(s)
Arabidopsis/genética , Galactanos/metabolismo , Galactosiltransferasas/metabolismo , Mucoproteínas/metabolismo , Arabidopsis/enzimología , Arabidopsis/fisiología , Arabidopsis/ultraestructura , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Pared Celular/metabolismo , Flores/enzimología , Flores/genética , Flores/fisiología , Flores/ultraestructura , Galactosiltransferasas/genética , Pleiotropía Genética , Germinación , Glucósidos/química , Glicosilación , Hidroxiprolina/metabolismo , Meristema/enzimología , Meristema/genética , Meristema/fisiología , Meristema/ultraestructura , Mucoproteínas/genética , Mutación , Especificidad de Órganos , Floroglucinol/análogos & derivados , Floroglucinol/química , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Tallos de la Planta/enzimología , Tallos de la Planta/genética , Tallos de la Planta/fisiología , Tallos de la Planta/ultraestructura , Biosíntesis de Proteínas , Estrés Salino , Semillas/enzimología , Semillas/genética , Semillas/fisiología , Semillas/ultraestructura
3.
J Laryngol Otol ; 129(8): 801-6, 2015 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-26087671

RESUMEN

OBJECTIVES: To evaluate the histopathological findings from post-treatment neck dissection of p16 positive and negative oropharyngeal carcinoma cases, after completion of chemoradiotherapy, and to question the role of neck dissection after a 'clinically complete response' to chemoradiotherapy. METHODS: Data were collected retrospectively from a cohort of patients treated with curative intent using chemoradiotherapy and post-treatment neck dissection. Primary tumours underwent p16 immunohistochemistry. Neck dissection specimens were examined for viable cancer cells. RESULTS: A total of 76 cases were assessed. Viable cancer cells were detected from neck dissection in 29 per cent of p16 negative cases. Locoregional recurrence occurred in 12.9 per cent of p16 negative cases. The association between p16 positivity in the primary tumour and histopathologically negative neck dissection was significant (p < 0.05). CONCLUSION: p16 status appeared to be an independent marker of disease control for the cohort in this study. The data raise questions about the role of post-treatment neck dissection in p16 positive cases with a 'clinically complete response' to chemoradiotherapy.


Asunto(s)
Biomarcadores de Tumor/análisis , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Quimioradioterapia Adyuvante , Disección del Cuello , Proteínas de Neoplasias/análisis , Neoplasias Orofaríngeas/patología , Neoplasias Orofaríngeas/terapia , Adulto , Anciano , Estudios de Cohortes , Terapia Combinada , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Femenino , Humanos , Ganglios Linfáticos/patología , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Orofaringe/patología , Valor Predictivo de las Pruebas , Pronóstico , Estudios Retrospectivos
4.
J Laryngol Otol ; 129(5): 496-501, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25994384

RESUMEN

OBJECTIVE: A large variety of techniques have been used for auricular haematoma management. The open surgical management of auricular haematoma involves incision, evacuation and the obliteration of dead space using biodegradable mattress sutures. Our goal was to describe open surgical management for primary, recurrent and spontaneous auricular haematoma. METHODS: Auricular haematoma patients who underwent open surgical management were prospectively audited (2010-2013). Information was collected on demographics, clinical presentation, aetiology, examination findings, previous interventions, details of open surgical management and post-operative follow up. RESULTS: In all, 12 male and 3 female patients with a mean age of 33 years (range 16-86 years) were evaluated. Contact sport injury was the most common aetiology. Ten patients had undergone previous unsuccessful interventions to treat auricular haematoma before open surgical management was performed. All patients were managed successfully without significant recurrence. One patient had a minor local reaccumulation which required reinsertion of a mattress suture. One elderly patient developed localised cellulitis which responded well to antibiotics. CONCLUSION: Open surgical management of auricular haematoma has been successful. The technique is simple and reliable, and can be accomplished in a clinical setting under local anaesthesia.


Asunto(s)
Drenaje/métodos , Pabellón Auricular/cirugía , Enfermedades del Oído/cirugía , Hematoma/cirugía , Técnicas de Sutura/instrumentación , Implantes Absorbibles , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Pabellón Auricular/lesiones , Enfermedades del Oído/etiología , Femenino , Hematoma/etiología , Humanos , Masculino , Ilustración Médica , Persona de Mediana Edad , Recurrencia , Resultado del Tratamiento , Adulto Joven
5.
J Laryngol Otol ; 127(11): 1141-2, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-24148186

RESUMEN

We present a novel way of providing and improving retraction whilst performing tracheostomies, using elasticated retractors. The benefits of this method include an improved surgical field and the facility for use by a single surgeon. This type of retraction could potentially be used in a variety of other head and neck procedures.


Asunto(s)
Traqueostomía/métodos , Elasticidad , Cabeza/cirugía , Humanos , Cuello/cirugía , Instrumentos Quirúrgicos , Traqueostomía/instrumentación
6.
Surgeon ; 11(6): 330-7, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23932799

RESUMEN

Retraction of tissues and anatomical structures is an essential component of all forms of surgery. The means by which operative access is gained through retraction are many and diverse. In this article, the various forms of retraction methods currently available are reviewed, with special reference to hand held, self-retaining and compliant techniques. The special challenges posed by laparoscopic surgery are considered and future developments in new retraction techniques are anticipated.


Asunto(s)
Ergonomía , Instrumentos Quirúrgicos , Procedimientos Quirúrgicos Operativos/métodos , Diseño de Equipo , Humanos
8.
Phys Rev Lett ; 110(13): 131802, 2013 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-23581310

RESUMEN

The beauty to up quark coupling constant |V(ub)| can be extracted from B → ρ e+ ν(e) combined with the form factors for D → K* e+ ν(e) and B → V ℓ+ ℓ- and D → ρ e+ ν(e). Using the entire CLEO-c ψ(3770) → DD event sample, corresponding to an integrated luminosity of 818 pb(-1) and approximately 5.4×10(6) DD events, we measure the form factors for the decays D0 → ρ- e+ ν(e) and D+ → ρ0 e+ ν(e) for the first time and the branching fractions with improved precision. A four-dimensional unbinned maximum likelihood fit determines the form factor ratios to be V(0)/A1(0)=1.48±0.15±0.05 and A2(0)/A1(0)=0.83±0.11±0.04. Assuming Cabibbo-Kobayashi-Maskawa unitarity, the known D meson lifetimes, and our measured branching fractions we obtain the form factor normalizations A1(0), A2(0), and V(0). We also present a measurement of the branching fraction for D+ → ω e+ ν(e) with improved precision.

10.
Phys Rev Lett ; 107(4): 041803, 2011 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-21866994

RESUMEN

Using 586 pb(-1) of e+ e- collision data at E(c.m.) = 4170 MeV, produced at the Cornell Electron Storage Ring collider and collected with the CLEO-c detector, we observe the process e+ e- → π+ π- h(c)(1P). We measure its cross section to be 15.6±2.3±1.9±3.0 pb, where the third error is due to the external uncertainty on the branching fraction of ψ(2S) → π0 h(c)(1P), which we use for normalization. We also find evidence for e+ e- → ηh(c)(1P) at 4170 MeV at the 3σ level and see hints of a rise in the e+ e- → π+ π- h(c)(1P) cross section at 4260 MeV.

11.
J Laryngol Otol ; 123(10): 1160-2, 2009 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-19573257

RESUMEN

OBJECTIVES: To establish the safety and effectiveness of nurse-led triage of otolaryngology out-patient referrals. METHOD: One hundred consecutive general practitioner referrals were reviewed by two consultants, two specialist registrars, two foundation year two senior house officers and two otolaryngology nurses. One of the nurses had received triage training. All referrals were triaged as 'urgent', 'soon' or 'routine' by each rater. RESULTS: The triage-trained nurse's results demonstrated good agreement with those of the senior consultant (80 per cent). This agreement was similar to that with the other consultant (77 per cent) and the specialist registrars (79 and 82 per cent). Weighted kappa statistics (correcting for chance agreement) showed that the triage-trained nurse had the second closest agreement to the senior consultant (0.66). After the actual out-patient appointments, retrospective review of the patients' case notes revealed that none had been triaged inappropriately by the trained nurse, and no urgent cases had been missed. CONCLUSIONS: Triage of out-patient referrals by trained ENT nurses is safe and effective, and is an acceptable alternative to traditional consultant vetting of referrals.


Asunto(s)
Otolaringología/normas , Pautas de la Práctica en Enfermería/normas , Triaje/normas , Humanos , Relaciones Interprofesionales , Otolaringología/educación , Servicio Ambulatorio en Hospital , Estudios Prospectivos , Derivación y Consulta/normas , Triaje/métodos
12.
Phys Rev Lett ; 102(1): 011801, 2009 Jan 09.
Artículo en Inglés | MEDLINE | ID: mdl-19257180

RESUMEN

Using 2.45x10;{7} psi(2S) decays collected with the CLEO-c detector at the Cornell Electron Storage Ring we present the most precise measurements of magnetic dipole transitions in the charmonium system. We measure B(psi(2S)-->gammaeta_{c})=(4.32+/-0.16+/-0.60)x10;{-3}, B(J/psi-->gammaeta_{c})/B(psi(2S)-->gammaeta_{c})=4.59+/-0.23+/-0.64, and B(J/psi-->gammaeta_{c})=(1.98+/-0.09+/-0.30)%. We observe a distortion in the eta_{c} line shape due to the photon-energy dependence of the magnetic dipole transition rate. We find that measurements of the eta_{c} mass are sensitive to the line shape, suggesting an explanation for the discrepancy between measurements of the eta_{c} mass in radiative transitions and other production mechanisms.

13.
Phys Rev Lett ; 101(19): 192001, 2008 Nov 07.
Artículo en Inglés | MEDLINE | ID: mdl-19113261

RESUMEN

We report the first observation of Upsilon(2S)-->etaUpsilon(1S), with a branching fraction B=(2.1(-0.6)+0.7(stat)+/-0.3(syst)) x 10(-4) and a statistical significance 5.3sigma. Data were acquired with the CLEO III detector at the CESR e+e(-) symmetric collider. This is the first process observed involving a b-quark spin flip. For related transitions, 90% confidence limits in units of 10(-4) are B(Upsilon(2S)-->pi0Upsilon(1S)) < 1.8, B(Upsilon(3S)-->etaUpsilon(1S)) < 1.8, B(Upsilon(3S)-->pi0Upsilon(1S)) < 0.7, and B(Upsilon(3S)-->pi0Upsilon(2S)) < 5.1.

14.
Phys Rev Lett ; 101(20): 201601, 2008 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-19113327

RESUMEN

In this Letter, we describe a search for lepton flavor violation (LFV) in the bottomonium system. We search for leptonic decays Upsilon(nS)-->mutau (n=1, 2, and 3) using the data collected with the CLEO III detector. We identify the tau lepton using its leptonic decay nu_{tau}nu[over ]_{e}e and utilize multidimensional likelihood fitting with probability density function shapes measured from independent data samples. We report our estimates of 95% C.L. upper limits on LFV branching fractions of Upsilon mesons. We interpret our results in terms of the exclusion plot for the energy scale of a hypothetical new interaction versus its effective LFV coupling in the framework of effective field theory.

15.
Phys Rev Lett ; 101(15): 151801, 2008 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-18999588

RESUMEN

Using a total of 2.74 x 10(7) decays of the psi(2S) collected with the CLEO-c detector, we present a study of chi(cJ)-->gammaV, where V=rho(0), omega, phi. The transitions chi(c1)-->gammarho(0 and chi(c1)-->gammaomega are observed with B(chi(c1)-->gammarho(0))=(2.43+/-0.19+/-0.22) x 10(-4) and B(chi(c1)-->gammaomega)=(8.3+/-1.5+/-1.2) x 10(-5). In the chi(c1)-->gammarho(0) transition, the final state meson is dominantly longitudinally polarized. Upper limits on the branching fractions of other chi(cJ) states to light vector mesons are presented.

16.
Phys Rev Lett ; 101(15): 151802, 2008 Oct 10.
Artículo en Inglés | MEDLINE | ID: mdl-18999589

RESUMEN

We search for a non-SM-like CP-odd Higgs boson (a(1)(0)) decaying to tau(+)tau(-) or mu(+)mu(-) in radiative decays of the Upsilon(1S). No significant signal is found, and upper limits on the product branching ratios are set. Our tau(+)tau(-) results are almost 2 orders of magnitude more stringent than previous upper limits. Our data provide no evidence for a Higgs state with a mass of 214 MeV decaying to mu(+)mu(-), previously proposed as an explanation for 3 Sigma(+)-->pmu(+)mu(-) events observed by the HyperCP experiment. Our results constrain NMSSM models.

17.
Phys Rev Lett ; 101(18): 182002, 2008 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-18999819

RESUMEN

We measure the mass of the eta;{'} meson using psi(2S)-->pi;{+}pi;{-}J/psi, J/psi-->gammaeta;{'} events acquired with the CLEO-c detector operating at the CESR e;{+}e;{-} collider. Using three decay modes, eta;{'}-->rho;{0}gamma, eta;{'}-->pi;{+}pi;{-}eta with eta-->gammagamma, and eta;{'}-->pi;{+}pi;{-}eta with eta-->pi;{+}pi;{-}pi;{0}, we find M_{eta;{'}}=957.793+/-0.054+/-0.036 MeV, in which the uncertainties are statistical and systematic, respectively. This result is consistent with but substantially more precise than the current world average.

18.
Phys Rev Lett ; 101(18): 182003, 2008 Oct 31.
Artículo en Inglés | MEDLINE | ID: mdl-18999820

RESUMEN

A precision measurement of the mass of the h_{c}(1P1) state of charmonium has been made using a sample of 24.5x10;{6} psi(2S) events produced in e;{+}e;{-} annihilation at the Cornell Electron Storage Ring (CESR). The reaction used was psi(2S)-->pi;{0}h_{c}, pi;{0}-->gammagamma, h_{c}-->gammaeta_{c}, and the reaction products were detected in the CLEO-c detector. Data have been analyzed both for the inclusive reaction and for the exclusive reactions in which eta_{c} decays are reconstructed in 15 hadronic decay channels. Consistent results are obtained in the two analyses. The averaged results of the present measurements are M(h_{c})=3525.28+/-0.19(stat.)+/-0.12(syst.) MeV, and B(psi(2S)-->pi;{0}h_{c})xB(h_{c}-->gammaeta_{c})=(4.19+/-0.32+/-0.45)x10;{-4}. Using the ;{3}P_{J} centroid mass, DeltaM_{hf}(1P) identical withM(chi_{cJ})-M(h_{c})=+0.02+/-0.19+/-0.13 MeV.

19.
Phys Rev Lett ; 101(10): 101801, 2008 Sep 05.
Artículo en Inglés | MEDLINE | ID: mdl-18851203

RESUMEN

We report the first observation of the decay J/psi-->3gamma. The signal has a statistical significance of 6sigma and corresponds to a branching fraction of B(J/psi-->3gamma)=(1.2+/-0.3+/-0.2)x10;{-5}, in which the errors are statistical and systematic, respectively. The measurement uses psi(2S)-->pi;{+}pi;{-}J/psi events acquired with the CLEO-c detector operating at the CESR e;{+}e;{-} collider.

20.
J Colloid Interface Sci ; 328(1): 147-52, 2008 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-18834992

RESUMEN

We present the results of a molecular dynamics study of a set of surface-tethered S(CH2CH2O)6CH3 chains. In this study, we analyze helix formation, in addition to thermal disorder, and find that spontaneous helix formation and details of helix morphology depend on charge partitioning ascribed to oxygen and the methylene groups. The effects of varying surface coverage as well as chain-surface interaction strength indicate that a set of approximately 7/2 helical structures oriented predominantly normal to the surface are formed at near full coverage. This occurs even though thermal disorder clearly precludes a description based on the concept of a perfect crystalline monolayer. Thermal fluctuations in chain morphology in the vicinity of the terminal methyl groups lead to the exposure of oxygen to the external environment. We also find that the persistence of compact helix-containing domains at partial surface coverage results in the formation of well-defined cavities or void regions that expose the bare surface, even in the presence of strong chain-surface attractive interactions.


Asunto(s)
Óxido de Etileno/química , Modelos Moleculares , Conformación Molecular , Compuestos de Azufre/química , Simulación por Computador , Calor , Enlace de Hidrógeno , Estructura Secundaria de Proteína
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