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1.
Phys Rev Lett ; 130(5): 051802, 2023 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-36800478

RESUMEN

The inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using 8.02×10^{20} protons-on-target in the NuMI beam. The sample of GeV electron neutrino interactions is the largest analyzed to date and is limited by ≃17% systematic rather than the ≃7.4% statistical uncertainties. The double-differential cross section in final-state electron energy and angle is presented for the first time, together with the single-differential dependence on Q^{2} (squared four-momentum transfer) and energy, in the range 1 GeV≤E_{ν}<6 GeV. Detailed comparisons are made to the predictions of the GENIE, GiBUU, NEUT, and NuWro neutrino event generators. The data do not strongly favor a model over the others consistently across all three cross sections measured, though some models have especially good or poor agreement in the single differential cross section vs Q^{2}.

2.
Phys Rev Lett ; 127(20): 201801, 2021 Nov 12.
Artículo en Inglés | MEDLINE | ID: mdl-34860065

RESUMEN

This Letter reports results from the first long-baseline search for sterile antineutrinos mixing in an accelerator-based antineutrino-dominated beam. The rate of neutral-current interactions in the two NOvA detectors, at distances of 1 and 810 km from the beam source, is analyzed using an exposure of 12.51×10^{20} protons-on-target from the NuMI beam at Fermilab running in antineutrino mode. A total of 121 of neutral-current candidates are observed at the far detector, compared to a prediction of 122±11(stat.)±15(syst.) assuming mixing only between three active flavors. No evidence for ν[over ¯]_{µ}→ν[over ¯]_{s} oscillation is observed. Interpreting this result within a 3+1 model, constraints are placed on the mixing angles θ_{24}<25° and θ_{34}<32° at the 90% C.L. for 0.05 eV^{2}≤Δm_{41}^{2}≤0.5 eV^{2}, the range of mass splittings that produces no significant oscillations at the near detector. These are the first 3+1 confidence limits set using long-baseline accelerator antineutrinos.

3.
Phys Rev Lett ; 123(15): 151803, 2019 Oct 11.
Artículo en Inglés | MEDLINE | ID: mdl-31702305

RESUMEN

The NOvA experiment has seen a 4.4σ signal of ν[over ¯]_{e} appearance in a 2 GeV ν[over ¯]_{µ} beam at a distance of 810 km. Using 12.33×10^{20} protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27 ν[over ¯]_{µ}→ν[over ¯]_{e} candidates with a background of 10.3 and 102 ν[over ¯]_{µ}→ν[over ¯]_{µ} candidates. This new antineutrino data are combined with neutrino data to measure the parameters |Δm_{32}^{2}|=2.48_{-0.06}^{+0.11}×10^{-3} eV^{2}/c^{4} and sin^{2}θ_{23} in the ranges from (0.53-0.60) and (0.45-0.48) in the normal neutrino mass hierarchy. The data exclude most values near δ_{CP}=π/2 for the inverted mass hierarchy by more than 3σ and favor the normal neutrino mass hierarchy by 1.9σ and θ_{23} values in the upper octant by 1.6σ.

4.
Phys Rev Lett ; 118(23): 231801, 2017 Jun 09.
Artículo en Inglés | MEDLINE | ID: mdl-28644674

RESUMEN

Results are reported from an improved measurement of ν_{µ}→ν_{e} transitions by the NOvA experiment. Using an exposure equivalent to 6.05×10^{20} protons on target, 33 ν_{e} candidates are observed with a background of 8.2±0.8 (syst.). Combined with the latest NOvA ν_{µ} disappearance data and external constraints from reactor experiments on sin^{2}2θ_{13}, the hypothesis of inverted mass hierarchy with θ_{23} in the lower octant is disfavored at greater than 93% C.L. for all values of δ_{CP}.

5.
Phys Rev Lett ; 118(15): 151802, 2017 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-28452513

RESUMEN

This Letter reports new results on muon neutrino disappearance from NOvA, using a 14 kton detector equivalent exposure of 6.05×10^{20} protons on target from the NuMI beam at the Fermi National Accelerator Laboratory. The measurement probes the muon-tau symmetry hypothesis that requires maximal θ_{23} mixing (θ_{23}=π/4). Assuming the normal mass hierarchy, we find Δm_{32}^{2}=(2.67±0.11)×10^{-3} eV^{2} and sin^{2}θ_{23} at the two statistically degenerate values 0.404_{-0.022}^{+0.030} and 0.624_{-0.030}^{+0.022}, both at the 68% confidence level. Our data disfavor the maximal mixing scenario with 2.6σ significance.

6.
J Appl Microbiol ; 121(2): 577-86, 2016 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-27187055

RESUMEN

AIMS: High rate algal ponds (HRAPs) have been suggested as replacements for waste stabilization ponds (WSPs) in Community Wastewater Management Systems (CWMS) used in rural South Australian (SA) towns. Treated effluent from CWMS is reused for irrigation. To manage the risk of human exposure to pathogens, the disinfection performance of HRAPs was validated using the common indicators Escherichia coli and F-RNA bacteriophage; aerobic spore-forming bacteria (ASFB) were used as indicators for protozoa. METHODS AND RESULTS: Using standard culture methods, the removal of the indicator organisms F-RNA bacteriophage, E. coli and ASFB by a HRAP at Kingston-on-Murray, SA, was measured. The mean log10 reduction values achieved for the F-RNA bacteriophage was 1·59 ± 0·82 log10 PFU 100 ml(-1) and for E. coli it was 2·13 ± 0·55 log10  E. coli MPN 100 ml(-1) . ASFB numbers in the treated pond effluent often exceeded those of the influent. CONCLUSIONS: The results show that HRAPs are able to remove viral and bacterial indicators to levels acceptable for subsurface irrigation of nonfood crops. Additionally, it was concluded that alternate environmental sources and the potential for regrowth made ASFB unsuitable indicators for pathogenic protozoa in natural pond systems. SIGNIFICANCE AND IMPACT OF THE STUDY: This study shows HRAPs would be suitable replacements for WSPs in CWMS schemes in regard to pathogen disinfection. Such demonstration of the treatment efficacy of HRAPs, together with their smaller land area requirements relative to WSPs, should facilitate their wider adoption in rural and remote communities.


Asunto(s)
Bacterias/crecimiento & desarrollo , Chlorophyta/fisiología , Estanques/microbiología , Aguas Residuales/microbiología , Purificación del Agua/métodos , Australia , Bacterias/aislamiento & purificación , Viabilidad Microbiana , Estanques/química , Eliminación de Residuos Líquidos/métodos
7.
Phys Rev Lett ; 113(24): 241803, 2014 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-25541766

RESUMEN

The T2K off-axis near detector ND280 is used to make the first differential cross-section measurements of electron neutrino charged current interactions at energies ∼1 GeV as a function of electron momentum, electron scattering angle, and four-momentum transfer of the interaction. The total flux-averaged ν(e) charged current cross section on carbon is measured to be ⟨σ⟩(ϕ)=1.11±0.10(stat)±0.18(syst)×10⁻³8 cm²/nucleon. The differential and total cross-section measurements agree with the predictions of two leading neutrino interaction generators, NEUT and GENIE. The NEUT prediction is 1.23×10⁻³8 cm²/nucleon and the GENIE prediction is 1.08×10⁻³8 cm²/nucleon. The total ν(e) charged current cross-section result is also in agreement with data from the Gargamelle experiment.

8.
Phys Rev Lett ; 112(18): 181801, 2014 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-24856687

RESUMEN

New data from the T2K neutrino oscillation experiment produce the most precise measurement of the neutrino mixing parameter θ23. Using an off-axis neutrino beam with a peak energy of 0.6 GeV and a data set corresponding to 6.57×10(20) protons on target, T2K has fit the energy-dependent νµ oscillation probability to determine oscillation parameters. The 68% confidence limit on sin(2)(θ23) is 0.514(-0.056)(+0.055) (0.511±0.055), assuming normal (inverted) mass hierarchy. The best-fit mass-squared splitting for normal hierarchy is Δm32(2)=(2.51±0.10)×10(-3) eV(2)/c(4) (inverted hierarchy: Δm13(2)=(2.48±0.10)×10(-3) eV(2)/c(4)). Adding a model of multinucleon interactions that affect neutrino energy reconstruction is found to produce only small biases in neutrino oscillation parameter extraction at current levels of statistical uncertainty.

9.
Phys Rev Lett ; 112(6): 061802, 2014 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-24580687

RESUMEN

The T2K experiment has observed electron neutrino appearance in a muon neutrino beam produced 295 km from the Super-Kamiokande detector with a peak energy of 0.6 GeV. A total of 28 electron neutrino events were detected with an energy distribution consistent with an appearance signal, corresponding to a significance of 7.3σ when compared to 4.92±0.55 expected background events. In the Pontecorvo-Maki-Nakagawa-Sakata mixing model, the electron neutrino appearance signal depends on several parameters including three mixing angles θ12, θ23, θ13, a mass difference Δm(32)(2) and a CP violating phase δ(CP). In this neutrino oscillation scenario, assuming |Δm(32)(2)|=2.4×10(-3) eV(2), sin(2)θ(23)=0.5, and Δm322>0 (Δm(32)(2)<0), a best-fit value of sin(2)2θ(13)=0.140(-0.032)(+0.038) (0.170(-0.037)(+0.045)) is obtained at δ(CP)=0. When combining the result with the current best knowledge of oscillation parameters including the world average value of θ(13) from reactor experiments, some values of δ(CP) are disfavored at the 90% C.L.

10.
Phys Rev Lett ; 111(21): 211803, 2013 Nov 22.
Artículo en Inglés | MEDLINE | ID: mdl-24313479

RESUMEN

The T2K Collaboration reports a precision measurement of muon neutrino disappearance with an off-axis neutrino beam with a peak energy of 0.6 GeV. Near detector measurements are used to constrain the neutrino flux and cross section parameters. The Super-Kamiokande far detector, which is 295 km downstream of the neutrino production target, collected data corresponding to 3.01×10(20) protons on target. In the absence of neutrino oscillations, 205±17 (syst) events are expected to be detected while only 58 muon neutrino event candidates are observed. A fit to the neutrino rate and energy spectrum, assuming three neutrino flavors and normal mass hierarchy yields a best-fit mixing angle sin2(θ23)=0.514±0.082 and mass splitting |Δm(32)(2)|=2.44(-0.15)(+0.17)×10(-3) eV2/c4. Our result corresponds to the maximal oscillation disappearance probability.

11.
Phys Rev Lett ; 107(4): 041801, 2011 Jul 22.
Artículo en Inglés | MEDLINE | ID: mdl-21866992

RESUMEN

The T2K experiment observes indications of ν(µ) → ν(e) appearance in data accumulated with 1.43×10(20) protons on target. Six events pass all selection criteria at the far detector. In a three-flavor neutrino oscillation scenario with |Δm(23)(2)| = 2.4×10(-3) eV(2), sin(2)2θ(23) = 1 and sin(2)2θ(13) = 0, the expected number of such events is 1.5±0.3(syst). Under this hypothesis, the probability to observe six or more candidate events is 7×10(-3), equivalent to 2.5σ significance. At 90% C.L., the data are consistent with 0.03(0.04) < sin(2)2θ(13) < 0.28(0.34) for δ(CP) = 0 and a normal (inverted) hierarchy.

12.
Scand J Med Sci Sports ; 21(6): e341-50, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21518010

RESUMEN

The purpose of this study was to examine the effects of exercising at different intensities over 7 weeks on components of physical fitness and CVD risk factors. Forty-seven boys and 10 girls, (16.4±0.7 years of age) were divided into a moderate, high intensity, or a control group. All participants had indices of obesity and blood pressure recorded in addition to four physical performance measures pre- and post-intervention. In addition, the intervention groups repeated the physical performance measures at the 4th week phase of the intervention. Following the intervention, significant improvements (P<0.05) in the high-intensity group were found in the 20 MSFT, agility, CMJ and 10 m sprint post-intervention. Participants in the moderate intensity group displayed significant improvements (P<0.05) in both the CMJ and 20 MSFT post-intervention. Body fat % significantly improved (P<0.01) in the moderate group only post-intervention. Interestingly, Systolic blood pressure significantly improved post-intervention (112±10 vs 106±11 mmHg) (P=0.017) in the high intensity group. In conclusion, high-intensity exercise over 7 weeks is a very time efficient means of improving important components of physical fitness in adolescents.


Asunto(s)
Ejercicio Físico/fisiología , Aptitud Física/fisiología , Adolescente , Enfermedades Cardiovasculares/prevención & control , Estudios de Cohortes , Femenino , Humanos , Masculino , Obesidad/prevención & control , Escocia , Encuestas y Cuestionarios
13.
Aust Vet J ; 87(7): 266-72, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19573149

RESUMEN

OBJECTIVE: To identify and gain an understanding of the influenza viruses circulating in wild birds in Australia. DESIGN: A total of 16,303 swabs and 3782 blood samples were collected and analysed for avian influenza (AI) viruses from 16,420 wild birds in Australia between July 2005 and June 2007. Anseriformes and Charadriiformes were primarily targeted. PROCEDURES: Cloacal, oropharyngeal and faecal (environmental) swabs were tested using polymerase chain reaction (PCR) for the AI type A matrix gene. Positive samples underwent virus culture and subtyping. Serum samples were analysed using a blocking enzyme-linked immunosorbent assay for influenza A virus nucleoprotein. RESULTS: No highly pathogenic AI viruses were identified. However, 164 PCR tests were positive for the AI type A matrix gene, 46 of which were identified to subtype. A total of five viruses were isolated, three of which had a corresponding positive PCR and subtype identification (H3N8, H4N6, H7N6). Low pathogenic AI H5 and/or H7 was present in wild birds in New South Wales, Tasmania, Victoria and Western Australia. Antibodies to influenza A were also detected in 15.0% of the birds sampled. CONCLUSIONS: Although low pathogenic AI virus subtypes are currently circulating in Australia, their prevalence is low (1.0% positive PCR). Surveillance activities for AI in wild birds should be continued to provide further epidemiological information about circulating viruses and to identify any changes in subtype prevalence.


Asunto(s)
Anseriformes , Enfermedades de las Aves/virología , Charadriiformes , Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/virología , Animales , Anticuerpos Antivirales/sangre , Australia/epidemiología , Enfermedades de las Aves/epidemiología , ADN Viral/química , ADN Viral/genética , Ensayo de Inmunoadsorción Enzimática/veterinaria , Virus de la Influenza A/genética , Gripe Aviar/sangre , Gripe Aviar/epidemiología , Reacción en Cadena de la Polimerasa/veterinaria , Prevalencia , Proteínas de la Matriz Viral/química , Proteínas de la Matriz Viral/genética
14.
Med J Aust ; 174(8): 425; author reply 426, 2001 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-11346095
15.
Clin Chem ; 47(5): 910-8, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11325896

RESUMEN

BACKGROUND: This investigation was undertaken to identify the structure of a novel immunoreactive metabolite derived from fosphenytoin that has been hypothesized previously as present in sera from renally impaired patients receiving this prodrug. METHODS: The metabolite was isolated from uremic sera using solid-phase extraction and HPLC. Structural analysis was performed using HPLC-tandem mass spectrometry, nuclear magnetic resonance (NMR), deuterium exchange, and chemical derivatization. Immunoreactivity was evaluated using a fluorescence polarization immunoassay. RESULTS: The metabolite had a parent ion at m/z 457 in the negative-ion mode and fragmented to yield the m/z 251 of phenytoin, as well as other mass fragments of phenytoin. Mass fragments associated with glucuronic acid were also present. The chromatographic peak corresponding to this metabolite demonstrated immunoreactivity sufficient to lead to falsely increased reported values for phenytoin immunoassays. The observed immunoreactivity was also proportional to the relative concentration of the metabolite in collected fractions. Analysis by NMR indicated the presence of phenyl groups with chemical shifts identical to those of phenytoin, as well as the presence of a methylene bridge, which was consistent with the same methylene bridge present on the phosphate ester of fosphenytoin. Comparative analysis of serum samples from renally impaired patients receiving phenytoin vs fosphenytoin using multiple reaction monitoring quantification demonstrated that this metabolite was associated with fosphenytoin administration. CONCLUSIONS: A unique immunoreactive oxymethylglucuronide metabolite derived from fosphenytoin has been isolated from sera from uremic patients receiving this prodrug.


Asunto(s)
Glucurónidos/sangre , Glucurónidos/aislamiento & purificación , Fenitoína/aislamiento & purificación , Fenitoína/metabolismo , Profármacos/metabolismo , Cromatografía Líquida de Alta Presión , Deuterio , Inmunoensayo de Polarización Fluorescente , Glucurónidos/química , Humanos , Espectroscopía de Resonancia Magnética , Espectrometría de Masas , Fenitoína/análogos & derivados , Fenitoína/sangre , Fenitoína/química , Fenitoína/uso terapéutico , Profármacos/uso terapéutico , Uremia/tratamiento farmacológico
16.
J Am Geriatr Soc ; 49(11): 1525-9, 2001 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-11890593

RESUMEN

OBJECTIVES: The effectiveness of percutaneous endoscopic gastrostomy (PEG) in older adults remains controversial. Although prior studies have examined the safety of PEG and its impact on nutrition, there are limited data on the economic costs. The purpose of this study is to describe the healthcare costs associated with PEG tube feeding over 1 year. DESIGN: Prospective cohort study. SETTING: Small community of approximately 60,000 residents served by two hospital systems. PARTICIPANTS: One hundred five (70%) of 150 patients age 60 and older receiving PEG over a 24-month period in the targeted community who permitted access to their medical records. MEASUREMENTS: Patients were interviewed at baseline and every 2 months for 1 year to obtain information on use of enteral formula, complication rates, and health services use. We obtained inpatient charge data for all hospitalizations and PEG procedures for 1 year. RESULTS: Censoring patients at death or 1 year post-PEG, the mean number of days of PEG tube feeding was 180 (range 5-365). The average cost for PEG tube feeding for this cohort of patients was $7,488 (median $3,691) in 1997 and 1998. The average daily cost of PEG tube feeding was $87.21 (median $33.50). The estimated cost of providing 1 year of feeding via PEG is $31,832 (median $12,227). The main components of this cost include the initial PEG procedure (29.4%), enteral formula (24.9%), and hospital charges for major complications (33.4%). CONCLUSIONS: Direct charges associated with PEG tube feeding over 1 year are conservatively estimated at $31,832; there was considerable variation in charges because of the cost of rare but costly major complications. Also, feeding patients via PEG resulted in cost shifts in terms of the primary payor. The economic cost of PEG tube feeding is another consideration in decision making for long-term enteral feeding among older adults.


Asunto(s)
Nutrición Enteral/economía , Gastroscopía/economía , Gastrostomía/economía , Costos de la Atención en Salud/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Indiana , Cuidados a Largo Plazo/economía , Masculino , Persona de Mediana Edad
17.
J Am Geriatr Soc ; 48(9): 1048-54, 2000 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10983903

RESUMEN

OBJECTIVE: Percutaneous endoscopic gastrostomy (PEG) has become the preferred method to provide enteral tube feeding to older adults who have difficulty eating, but the impact of PEG on patient outcomes is poorly understood. The objective of this study was to describe changes in nutrition, functional status, and health-related quality of life among older adults receiving PEG. DESIGN: A prospective cohort study. SETTING: A small community of approximately 60,000 residents served by two hospital systems. PARTICIPANTS: One hundred fifty patients aged 60 and older receiving PEG from one of the four gastroenterologists practicing in the targeted community. MEASUREMENTS: Patients were assessed at baseline and every 2 months for 1 year to obtain clinical characteristics, process of care data, physical and cognitive function, subjective health status, nutritional status, complications, and mortality. RESULTS: Over a 14-month period, 150 patients received PEG tubes in the targeted community; the mean age was 78.9. The most frequent indications for the PEG were stroke (40.7%), neurodegenerative disorders (34.7%), and cancer (13.3%). All measures of functional status, cognitive status, severity of illness, comorbidity, and quality of life demonstrated profound and life-threatening impairment; 30-day mortality was 22% and 1-year mortality was 50%. Among patients surviving 60 days or more, at least 70% had no significant improvement in functional, nutritional, or subjective health status. Serious complications were rare, but most patients experienced symptomatic problems that they attributed to the enteral tube feeding. CONCLUSIONS: PEG tube feeding in severely and chronically ill older adults can be accomplished safely. However, there are important patient burdens associated with the PEG and there was limited evidence that the procedure improves functional, nutritional, or subjective health status in this cohort of older adults. The issues raised in this descriptive study provide impetus for a randomized trial of PEG tube feeding compared with alternative methods of patient care for older adults with difficulty eating.


Asunto(s)
Actividades Cotidianas , Gastroscopía , Gastrostomía , Estado Nutricional , Calidad de Vida , Factores de Edad , Anciano , Anciano de 80 o más Años , Actitud Frente a la Salud , Nutrición Enteral/efectos adversos , Nutrición Enteral/mortalidad , Nutrición Enteral/psicología , Femenino , Gastroscopía/efectos adversos , Gastroscopía/mortalidad , Gastroscopía/psicología , Gastrostomía/efectos adversos , Gastrostomía/mortalidad , Gastrostomía/psicología , Evaluación Geriátrica , Humanos , Masculino , Persona de Mediana Edad , Evaluación de Procesos y Resultados en Atención de Salud , Estudios Prospectivos , Análisis de Supervivencia , Resultado del Tratamiento
18.
Optom Vis Sci ; 77(1): 51-7, 2000 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-10654859

RESUMEN

PURPOSE: To test the hypothesis that access to and amount of eye care services in Jamaica are inadequate and that this is related to insufficient eye care personnel and legal limitations on optometric practice in Jamaica. METHODS: An eye care provider survey, a consumer survey, and a literature search were used for data collection. The consumer sample consisted of 500 subjects (aged 16 to 84 years or older) recruited from a stratified random sample of food markets in Jamaica. The provider sample consisted of 10 ophthalmologists and 10 optometrists, randomly selected from licensing rosters. Adequacy of amount of eye care services was measured by comparing the frequency of eye examinations in Jamaica with professional practice guidelines. Access was measured by the eye provider to population ratio compared with calculated need for adequate care. RESULTS: Only 38.6% of the study population had received an eye examination within 3 years and only 23.4% reported having eye examinations at least once every 3 years. Over 43% had never received an eye examination. The total eye care provider/population ratio was only 2.04/100,000 and only 1.32/100,000 when optometrists are excluded. CONCLUSION: Access to and amount of eye care services are severely inadequate in Jamaica. Outdated optometric laws governing the activities of eye care professionals compounds the problem.


Asunto(s)
Política de Salud , Accesibilidad a los Servicios de Salud/normas , Fuerza Laboral en Salud/normas , Optometría , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Oftalmopatías/diagnóstico , Oftalmopatías/terapia , Femenino , Accesibilidad a los Servicios de Salud/organización & administración , Humanos , Jamaica , Masculino , Persona de Mediana Edad , Optometría/economía , Optometría/legislación & jurisprudencia , Estudios Retrospectivos , Encuestas y Cuestionarios
19.
J Am Geriatr Soc ; 47(9): 1105-9, 1999 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-10484254

RESUMEN

OBJECTIVE: To describe clinical decision-making for percutaneous endoscopic gastrostomy from the perspective of patients, caregivers, and physicians. DESIGN: A prospective cohort study. SETTING AND PATIENTS: All patients aged 60 and older receiving percutaneous endoscopic gastrostomies in a defined community over a 16-month period. MAIN OUTCOMES MEASURES: Either patients or their surrogate decision-makers completed a semistructured face-to-face interview to map out the information gathering process, expectations, and discussants involved in the decision to proceed with gastrostomy feeding. Physicians completed a written questionnaire to determine their likelihood of recommending percutaneous endoscopic gastrostomy, their involvement in the decision-making and recommendation process, and sources of perceived pressure in the decision-making. RESULTS: We identified 100 patients who received percutaneous endoscopic gastrostomy during the study window and 82 primary care physicians who provided care in the defined community. The most common reasons for the procedure were stroke, neurologic disease, and cancer. Patients or their surrogate decision-makers reported multiple discussants, incomplete information, and considerable distress in arriving at the decision to proceed with artificial feeding. This distress was usually in the context of an acute and debilitating illness that often overshadowed the decision about artificial feeding. The decision for gastrostomy often appeared to be a "non-decision" in the sense that decision-makers perceived few alternatives. Physicians also reported considerable distress in arriving at recommendations to proceed with percutaneous endoscopic gastrostomy, including perceived pressures from families or other healthcare professionals. Physicians have clear patterns of triage for percutaneous endoscopic gastrostomy, but the assumptions underlying these patterns are not well supported by the medical literature. CONCLUSIONS: Patients, caregivers, and physicians are often compelled to make decisions about long-term enteral feeding under tragic circumstances and with incomplete information. Decision-makers typically do not perceive any acceptable alternatives. Because data on these patients' long-term functional outcomes are lacking, decision-makers appear to focus primarily on the short-term safety of the procedure and the potential for improved nutrition.


Asunto(s)
Toma de Decisiones , Nutrición Enteral , Gastrostomía , Servicios de Salud para Ancianos , Anciano , Cuidadores/psicología , Redes Comunitarias , Nutrición Enteral/psicología , Femenino , Gastrostomía/psicología , Estado de Salud , Humanos , Masculino , Persona de Mediana Edad , Pacientes/psicología , Relaciones Médico-Paciente , Médicos/psicología , Estudios Prospectivos , Medición de Riesgo , Encuestas y Cuestionarios , Incertidumbre
20.
Clin Exp Rheumatol ; 15(5): 535-9, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9307862

RESUMEN

OBJECTIVE: To study serum levels of von Willebrand factor antigen (vWF:Ag) and anti-endothelial cell antibodies (AECA) in pregnancies with systemic lupus erythematosus (SLE) compared to healthy pregnancies and to evaluate their correlation with disease activity and fetal outcome. METHODS: Twenty-four patients with SLE were compared with 26 healthy pregnancies. vWF:Ag and AECA levels were measured by ELISA. RESULTS: In lupus pregnancies vWF:Ag and AECA levels were significantly elevated compared to healthy pregnancies (vWF:Ag: 255 +/- 160%, 10/24 positive vs 135 +/- 59%, 1/26 positive, p = 0.006; AECA Binding Index: 36 +/- 29%, 5/24 positive vs 17 +/- 16%, 1/26 positive, p = 0.002). When samples taken during follow-up were evaluated, vWF:Ag was positive in 21/27 (78%) of the samples during exacerbations compared to 4/25 (16%) in remission. Only 5/27 (19%) of the samples during exacerbations and none during remission were positive for AECA. Samples during three pregnancy failures were positive for vWF:Ag, but not for AECA. Of the 13 samples taken from the mothers of 4 babies with neo-natal lupus, 10 were positive for vWF:Ag and three for AECA. No correlations of anti-cardiolipin antibodies (aCL) were seen either with vWF:Ag or AECA titres. CONCLUSION: Compared to healthy pregnancies, vWF:Ag and AECA levels are increased in lupus pregnancies. vWF:Ag levels also correlated with active disease.


Asunto(s)
Lupus Eritematoso Sistémico/complicaciones , Complicaciones Cardiovasculares del Embarazo/inmunología , Vasculitis/etiología , Aborto Espontáneo/etiología , Aborto Espontáneo/inmunología , Adulto , Anticuerpos Anticardiolipina/sangre , Antígenos/sangre , Autoanticuerpos/inmunología , Biomarcadores , Ensayo de Inmunoadsorción Enzimática , Femenino , Humanos , Trabajo de Parto Prematuro/etiología , Trabajo de Parto Prematuro/inmunología , Embarazo , Complicaciones Cardiovasculares del Embarazo/etiología , Factor de von Willebrand/inmunología
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