Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 496
Filtrar
Más filtros

Tipo del documento
Intervalo de año de publicación
1.
Nature ; 576(7786): 228-231, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31802006

RESUMEN

The prediction of a supersonic solar wind1 was first confirmed by spacecraft near Earth2,3 and later by spacecraft at heliocentric distances as small as 62 solar radii4. These missions showed that plasma accelerates as it emerges from the corona, aided by unidentified processes that transport energy outwards from the Sun before depositing it in the wind. Alfvénic fluctuations are a promising candidate for such a process because they are seen in the corona and solar wind and contain considerable energy5-7. Magnetic tension forces the corona to co-rotate with the Sun, but any residual rotation far from the Sun reported until now has been much smaller than the amplitude of waves and deflections from interacting wind streams8. Here we report observations of solar-wind plasma at heliocentric distances of about 35 solar radii9-11, well within the distance at which stream interactions become important. We find that Alfvén waves organize into structured velocity spikes with duration of up to minutes, which are associated with propagating S-like bends in the magnetic-field lines. We detect an increasing rotational component to the flow velocity of the solar wind around the Sun, peaking at 35 to 50 kilometres per second-considerably above the amplitude of the waves. These flows exceed classical velocity predictions of a few kilometres per second, challenging models of circulation in the corona and calling into question our understanding of how stars lose angular momentum and spin down as they age12-14.

2.
Eur Radiol ; 33(4): 2995-3003, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36422646

RESUMEN

OBJECTIVES: To systematically investigate the usability of virtual non-contrast reconstructions (VNC) derived from dual-layer CT (DLCT) for detection and size measurements of kidney stones with regards to different degrees of surrounding iodine-induced attenuation and radiation dose. METHODS: Ninety-two kidney stones of varying size (3-14 mm) and composition were placed in a phantom filled with different contrast media/water mixtures exhibiting specific iodine-induced attenuation (0-1500 HU). DLCT-scans were acquired using CTDIvol of 2 mGy and 10 mGy. Conventional images (CI) and VNC0H-1500HU were reconstructed. Reference stone size was determined using a digital caliper (Man-M). Visibility and stone size were assessed. Statistical analysis was performed using the McNemar test, Wilcoxon test, and the coefficient of determination. RESULTS: All stones were visible on CI0HU and VNC200HU. Starting at VNC400 HU, the detection rate decreased with increasing HU and was significantly lower as compared to CI0HU on VNC≥ 600HU (100.0 vs. 94.0%, p < 0.05). The overall detection rate was higher using 10 mGy as compared to 2 mGy protocol (87.9 vs. 81.8%; p < 0.001). Stone size was significantly overestimated on all VNC compared to Man-M (7.0 ± 3.5 vs. 6.6 ± 2.8 mm, p < 0.001). Again, the 10 mGy protocol tended to show a better correlation with Man-M as compared to 2 mGy protocol (R2 = 0.39-0.68 vs. R2 = 0.31-0.57). CONCLUSIONS: Detection and size measurements of kidney stones surrounded by contrast media on VNC are feasible. The detection rate of kidney stones decreases with increasing iodine-induced attenuation and with decreasing radiation dose as well as stone size, while remaining comparable to CI0HU on VNC ≤ 400 HU. KEY POINTS: • The detection rate of kidney stones on VNC depends on the surrounding iodine-induced attenuation, the used radiation dose, and the stone size. • The detection rate of kidney stones on VNC decreases with greater iodine-induced attenuation and with lower radiation dose, particularly in small stones. • The visibility of kidney stones on VNC ≤ 400 HU remains comparable to true-non-contrast scans even when using a low-dose technique.


Asunto(s)
Yodo , Cálculos Renales , Imagen Radiográfica por Emisión de Doble Fotón , Masculino , Humanos , Medios de Contraste , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Cálculos Renales/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos
3.
J Community Health ; 47(6): 949-958, 2022 12.
Artículo en Inglés | MEDLINE | ID: mdl-35925435

RESUMEN

The Affordable Care Act includes a call for community health care workers (CHWs) to be integrated into health care delivery systems to improve health care quality. In recent years, there have been increasing calls for community-based participatory research (CBPR) and patient-centered outcomes research (PCOR), as such types of research hold much potential for identifying interventions to reduce health and health care disparities. Yet, little is known about the research training, knowledge, experience, and even interest of CHWs in these types of research or in health research in general (HR). Thus, the purposes of this study include determining if there are differences between participating CHWs (N = 202) in their levels of training, knowledge, experience, and interest in relation to CBPR, PCOR and HR. Findings suggest that certified CHWs, as compared to non-certified CHWs, have significantly higher knowledge levels across all three types of research (ß = 1.3, p = .007). Additionally, participants had significantly higher knowledge of HR compared to CBPR (ß = 0.5, p = .015), but not higher than their knowledge of PCOR (p > .5). Qualitative data analyses performed to determine research areas of interest among the participating CHWs resulted in eighteen major research interest themes. Examples of these major themes are chronic illness (n = 95), health promotion (n = 39), healthcare services and administration (n = 30), mental health (n = 29), and research evaluation and methodology (n = 26). Together, the findings suggest that though CHWs have an interest in a wide range of health research areas, they could benefit from research trainings tailored to their responsibilities and interests.


Asunto(s)
Agentes Comunitarios de Salud , Patient Protection and Affordable Care Act , Estados Unidos , Humanos , Agentes Comunitarios de Salud/psicología , Atención a la Salud , Promoción de la Salud , Investigación Participativa Basada en la Comunidad , Investigación Cualitativa
4.
Phys Rev Lett ; 127(25): 255101, 2021 Dec 17.
Artículo en Inglés | MEDLINE | ID: mdl-35029449

RESUMEN

The high temperatures and strong magnetic fields of the solar corona form streams of solar wind that expand through the Solar System into interstellar space. At 09:33 UT on 28 April 2021 Parker Solar Probe entered the magnetized atmosphere of the Sun 13 million km above the photosphere, crossing below the Alfvén critical surface for five hours into plasma in casual contact with the Sun with an Alfvén Mach number of 0.79 and magnetic pressure dominating both ion and electron pressure. The spectrum of turbulence below the Alfvén critical surface is reported. Magnetic mapping suggests the region was a steady flow emerging on rapidly expanding coronal magnetic field lines lying above a pseudostreamer. The sub-Alfvénic nature of the flow may be due to suppressed magnetic reconnection at the base of the pseudostreamer, as evidenced by unusually low densities in this region and the magnetic mapping.

5.
Osteoarthritis Cartilage ; 28(9): 1202-1213, 2020 09.
Artículo en Inglés | MEDLINE | ID: mdl-32652238

RESUMEN

OBJECTIVE: To quantify preferences for attributes of potential analgesic treatments for moderate-to-severe pain associated with osteoarthritis (OA) and/or chronic low back pain (CLBP) as relevant to injectable nerve growth factor (NGF)-inhibitors, nonsteroidal anti-inflammatory drugs (NSAIDs), and opioids. METHODS: We used a discrete-choice experiment (DCE) to elicit preferences for attributes of OA and CLBP pharmaceutical treatments, and a best-worst scaling (BWS) exercise to further characterize the relative importance of treatment-related side-effect risks. The survey was completed online by 602 US residents with self-reported chronic, moderate-to-severe OA pain and/or CLBP who had tried, had contraindications for, or were unwilling to take currently available pharmaceutical therapies. In the DCE, respondents repeatedly chose between two hypothetical treatments defined by six attributes (symptom control; treatment-related risks of (1) severe joint problems, (2) heart attack, and (3) physical dependence; mode/frequency of administration; and cost). In the BWS exercise, respondents evaluated ten side-effect risks. Random-parameters logit models were estimated; conditional relative attribute importance, maximum acceptable risks, and willingness to pay were calculated. RESULTS: The most important DCE attributes were improving symptom control (scaled conditional relative importance, 10.00) and reducing risk of physical dependence (6.99). The three most important BWS attributes were, in rank order, risks of stroke, physical dependence, and heart attack. Respondents were willing to accept a > 4% treatment-related risk of severe joint problems for even modest symptom improvement. CONCLUSION: A pharmaceutical treatment with a risk of severe joint problems was viewed as an acceptable alternative to other treatments with comparable efficacy but risks associated with NSAIDs or opioids.


Asunto(s)
Analgésicos Opioides/uso terapéutico , Antiinflamatorios no Esteroideos/uso terapéutico , Artralgia/tratamiento farmacológico , Conducta de Elección , Dolor Crónico/tratamiento farmacológico , Dolor de la Región Lumbar/tratamiento farmacológico , Osteoartritis/tratamiento farmacológico , Prioridad del Paciente , Adulto , Anciano , Anciano de 80 o más Años , Analgésicos/uso terapéutico , Progresión de la Enfermedad , Femenino , Gastos en Salud , Humanos , Inyecciones , Masculino , Persona de Mediana Edad , Infarto del Miocardio , Factor de Crecimiento Nervioso/antagonistas & inhibidores , Medición de Riesgo , Estados Unidos , Adulto Joven
6.
Anaesthesist ; 69(4): 254-261, 2020 04.
Artículo en Alemán | MEDLINE | ID: mdl-32166396

RESUMEN

Arterial hypotension during cesarean delivery under spinal anesthesia can cause maternal and fetal adverse effects. Therefore, current guidelines recommend the continuous and preferably prophylactic use of vasopressors, emphasizing the use of alpha-agonists, such as phenylephrine. Besides a left lateral uterine displacement either an intravenous colloid preloading or a crystalloid co-loading is recommended. The blood pressure goal is to maintain a systolic arterial blood pressure of at least 90% of the initial baseline value and to avoid a drop to less than 80% of this baseline. To achieve this goal a prophylactic continuous phenylephrine infusion with an adjustable flow rate is recommended. It is advised to start with an initial dose of 25-50 µg/min, initiated immediately following the intrathecal injection of the local anesthetic and titrated according to the vital parameters. Parturients with cardiac diseases should be preoperatively evaluated following individual hemodynamic goals.


Asunto(s)
Anestesia Obstétrica/efectos adversos , Anestesia Raquidea/efectos adversos , Cesárea , Hipotensión/tratamiento farmacológico , Hipotensión/etiología , Adulto , Femenino , Humanos , Fenilefrina/uso terapéutico , Embarazo , Vasoconstrictores/uso terapéutico
7.
Phys Rev Lett ; 123(14): 145101, 2019 Oct 04.
Artículo en Inglés | MEDLINE | ID: mdl-31702218

RESUMEN

Reliable models of the solar wind in the near-Earth space environment may constrain conditions close to the Sun. This is relevant to NASA's contemporary innerheliospheric mission Parker Solar Probe. Among the outstanding issues is how to explain the solar wind temperature isotropy. Perpendicular and parallel proton and electron temperatures near 1 AU are theoretically predicted to be unequal, but in situ observations show quasi-isotropy sufficiently below the instability threshold condition. This has not been satisfactorily explained. The present Letter shows that the dynamical coupling of electrons and protons via collisional processes and instabilities may contribute toward the resolution of this problem.

8.
Phys Rev Lett ; 120(20): 205102, 2018 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-29864295

RESUMEN

We perform a statistical assessment of solar wind stability at 1 AU against ion sources of free energy using Nyquist's instability criterion. In contrast to typically employed threshold models which consider a single free-energy source, this method includes the effects of proton and He^{2+} temperature anisotropy with respect to the background magnetic field as well as relative drifts between the proton core, proton beam, and He^{2+} components on stability. Of 309 randomly selected spectra from the Wind spacecraft, 53.7% are unstable when the ion components are modeled as drifting bi-Maxwellians; only 4.5% of the spectra are unstable to long-wavelength instabilities. A majority of the instabilities occur for spectra where a proton beam is resolved. Nearly all observed instabilities have growth rates γ slower than instrumental and ion-kinetic-scale timescales. Unstable spectra are associated with relatively large He^{2+} drift speeds and/or a departure of the core proton temperature from isotropy; other parametric dependencies of unstable spectra are also identified.

9.
Acta Neurol Scand ; 138(3): 259-262, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29633241

RESUMEN

BACKGROUND: Nearly 10 years after its introduction into the market, the significance of lacosamide in genetic generalized epilepsies is still unclear. Its new mode of action may qualify lacosamide as a therapeutic agent in this entity, but only a limited number of cases have been published so far. AIM: To describe the efficacy of lacosamide as treatment in a patient with the absence status epilepticus. METHOD: We report on a 28-year-old woman with genetic generalized epilepsy who suffered recurrent absence status epilepticus during video-EEG-monitoring. After treatment failure of first- and second-line medication, lacosamide was administered. The outcome in this patient was evaluated, and a systematic literature review was performed for the use of lacosamide in the absence status epilepticus. RESULTS: After application of 400 mg lacosamide intravenously, the absence status epilepticus terminated within 30 minutes. No further seizures or epileptiform discharges reoccurred until the end of video-EEG-Monitoring 3 days later. CONCLUSIONS: The role of lacosamide as a therapeutic option in patients with the absence status epilepticus is unclear. Only two cases have been reported so far with conflicting results. Further randomized controlled studies are required to validate the relevance of lacosamide as treatment for status epilepticus in genetic generalized and the absence epilepsy.


Asunto(s)
Acetamidas/uso terapéutico , Anticonvulsivantes/uso terapéutico , Epilepsia Tipo Ausencia/tratamiento farmacológico , Adulto , Femenino , Humanos , Lacosamida , Convulsiones/tratamiento farmacológico
10.
Acta Anaesthesiol Scand ; 62(3): 347-356, 2018 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-29210062

RESUMEN

BACKGROUND: Mechanical ventilation with oxygen is life-saving, however, may result in hyperoxia. The aim was to analyse the incidence and duration of hyperoxia burden and related in-hospital mortality in critically ill patients. METHODS: Patients of all ages admitted to intensive care units (ICUs) and with mechanical ventilation for at least seven consecutive days were included in this single centre retrospective medical record audit. The main outcome measure was time-weighted arterial partial pressure of oxygen (PaO2 ) over 7 days. Logistic regression for association with in-hospital mortality and propensity score matching was performed. RESULTS: In total, 20,889 arterial blood gases of 419 patients were analysed. Time-weighted mean PaO2 was 14.0 ± 2.4 kPa. Time-weighted mean FiO2 was 49.2 ± 12.1%. Seventy-six (18.1%) patients showed continuous hyperoxia exposure, defined as time-weighted mean PaO2 > 16 kPa. Duration of hyperoxia, hypoxia (PaO2 < 8 kPa) and normoxia (PaO2 8-16 kPa) were 37.9 ± 31.0 h (23.7%), 4.9 ± 9.5 h (3.1%), and 116.8 ± 29.6 h (73.2%). Hyperoxia occurred especially at low to moderate FiO2 in patients of first and second age quartiles (1-57 years) with smaller SAPS2 score. In-hospital mortality of patients with hyperoxia (32.9%) or normoxia did not differ (35.9%; P = 0.691). Conditional logistic regression showed no association between hyperoxia and in-hospital mortality (OR 1.46; 95%CI 0.72-2.96; P = 0.29). CONCLUSION: Substantial hyperoxia burden was observed in ICU patients. Young patients with less comorbidities showed hyperoxic episodes more often, especially with lower FiO2 . Hyperoxia during 7 days of mechanical ventilation did not correlate to increased in-hospital mortality.


Asunto(s)
Enfermedad Crítica/mortalidad , Mortalidad Hospitalaria , Hiperoxia/epidemiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Análisis de Datos , Femenino , Humanos , Incidencia , Lactante , Modelos Logísticos , Masculino , Persona de Mediana Edad , Oxígeno/sangre , Estudios Retrospectivos , Adulto Joven
11.
Public Health ; 162: 58-62, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29975861

RESUMEN

OBJECTIVES: Public health initiatives to increase parental awareness about children's obesity have become more prominent in the past decade. These initiatives may contribute to increased concern in parents for their children's weight, even if their children are at a healthy weight. The aim of the present study was to document trends in parental (N = 365; 67.9% female) concern for their children's weight from 2002 to 2012 using surveys on health and eating behaviors. STUDY DESIGN: Participants (N = 365) were parents who completed surveys in 2002 and were followed up in 2012 as part of a longitudinal epidemiological study of eating attitudes and behavior. METHODS: McNemar's test and logistic regression models estimated changes in and predictors of parental concern. RESULTS: In 2002, 36.5% of participants indicated concern for their children's weight, which rose to 54.4% in 2012. Parents of overweight children were more likely to report concern than parents of average-weight children at baseline and 10-year follow-up. However, concern increased significantly even among parents of average-weight children, rising from 28.7% to 41.6% (McNemar's test statistic: 8.20, P = .002). Secondary analyses revealed that parents' baseline drive for thinness predicted increased likelihood of concern in these parents (odds ratio: 1.10, P = .04). CONCLUSION: Findings support the need for future research to examine consequences of societal messages about pediatric obesity.


Asunto(s)
Actitud Frente a la Salud , Peso Corporal , Padres/psicología , Adulto , Niño , Femenino , Humanos , Estudios Longitudinales , Masculino , Obesidad Infantil/psicología , Prevalencia , Encuestas y Cuestionarios
12.
Hum Reprod ; 32(2): 272-283, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27994001

RESUMEN

STUDY QUESTION: Do short-term and long-term exposures to low-dose folic acid supplementation alter DNA methylation in sperm? SUMMARY ANSWER: No alterations in sperm DNA methylation patterns were found following the administration of low-dose folic acid supplements of 400 µg/day for 90 days (short-term exposure) or when pre-fortification of food with folic acid and post-fortification sperm samples (long-term exposure) were compared. WHAT IS KNOWN ALREADY: Excess dietary folate may be detrimental to health and DNA methylation profiles due to folate's role in one-carbon metabolism and the formation of S-adenosyl methionine, the universal methyl donor. DNA methylation patterns are established in developing male germ cells and have been suggested to be affected by high-dose (5 mg/day) folic acid supplementation. STUDY DESIGN, SIZE, DURATION: This is a control versus treatment study where genome-wide sperm DNA methylation patterns were examined prior to fortification of food (1996-1997) in men with no history of infertility at baseline and following 90-day exposure to placebo (n = 9) or supplement containing 400 µg folic acid/day (n = 10). Additionally, pre-fortification sperm DNA methylation profiles (n = 19) were compared with those of a group of post-fortification (post-2004) men (n = 8) who had been exposed for several years to dietary folic acid fortification. PARTICIPANTS/MATERIALS, SETTING, METHODS: Blood and seminal plasma folate levels were measured in participants before and following the 90-day treatment with placebo or supplement. Sperm DNA methylation was assessed using the whole-genome and genome-wide techniques, MassArray epityper, restriction landmark genomic scanning, methyl-CpG immunoprecipitation and Illumina HumanMethylation450 Bead Array. MAIN RESULTS AND THE ROLE OF CHANCE: Following treatment, supplemented individuals had significantly higher levels of blood and seminal plasma folates compared to placebo. Initial first-generation genome-wide analyses of sperm DNA methylation showed little evidence of changes when comparing pre- and post-treatment samples. With Illumina HumanMethylation450 BeadChip arrays, no significant changes were observed in individual probes following low-level supplementation; when compared with those of the post-fortification cohort, there were also few differences in methylation despite exposure to years of fortified foods. LARGE SCALE DATA: Illumina HumanMethylation450 BeadChip data from this study have been submitted to the NCBI Gene Expression Omnibus under the accession number GSE89781. LIMITATIONS, REASONS FOR CAUTION: This study was limited to the number of participants available in each cohort, in particular those who were not exposed to early (pre-1998) fortification of food with folic acid. While genome-wide DNA methylation was assessed with several techniques that targeted genic and CpG-rich regions, intergenic regions were less well interrogated. WIDER IMPLICATIONS OF THE FINDINGS: Overall, our findings provide evidence that short-term exposure to low-dose folic acid supplements of 400 µg/day, over a period of 3 months, a duration of time that might occur during infertility treatments, has no major impact on the sperm DNA methylome. STUDY FUNDING/COMPETING INTERESTS: This work was supported by a grant to J.M.T. from the Canadian Institutes of Health Research (CIHR: MOP-89944). The authors have no conflicts of interest to declare.


Asunto(s)
Metilación de ADN/efectos de los fármacos , Suplementos Dietéticos , Ácido Fólico/administración & dosificación , Espermatozoides/metabolismo , Adulto , Método Doble Ciego , Ácido Fólico/análisis , Humanos , Masculino , Semen/química , Espermatozoides/efectos de los fármacos , Adulto Joven
13.
Br J Anaesth ; 118(3): 400-406, 2017 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-28199523

RESUMEN

Background: Cerebral microemboli (ME) are frequently generated during orthopaedic surgery and may impair cerebral integrity. However, the nature of cerebral ME, being either of solid or gaseous origin, is poorly investigated. Our primary aim was to determine both the frequency and nature of cerebral ME in generally anaesthetised patients undergoing major orthopaedic surgery. Methods: Fifty patients (hip/knee/shoulder prosthesis, spine surgery) were enrolled. Cerebral ME and cerebral blood flow velocity (CBFV) were determined in both middle cerebral arteries for 15 min preoperatively and postoperatively, using transcranial Doppler ultrasound. Cerebral tissue oxygen index, determined by near-infrared spectroscopy, was further examined. Statistical analysis was carried out using the Wilcoxon matched-pairs signed-ranks test (median (25 th ; 75 th percentile), P < 0.05). Results: Overall the frequency of postoperative cerebral ME rose to 600% of preoperative values. Primarily gaseous ME occurred preoperatively and postoperatively [19 (6; 63) vs 116 (24; 373), P < 0.001], while the number of solid ME was negligibly small [1 (0; 2) vs 2 (0; 6), P < 0.001]. CBFV and cerebral tissue oxygen index remained unaltered bilaterally before and after surgery. Conclusions: Our findings indicate that cerebral ME considerably increase after major orthopaedic surgery under general anaesthesia. The predominant accumulation of gaseous ME and their preoperative occurrence, suggest that the general anaesthesia and individual patient factors may contribute to the embolic load in addition to orthopaedic surgery. Clinical trial registration: . NCT02340416.


Asunto(s)
Embolia Intracraneal/diagnóstico por imagen , Procedimientos Ortopédicos , Complicaciones Posoperatorias/diagnóstico por imagen , Ultrasonografía Doppler Transcraneal/métodos , Anciano , Anciano de 80 o más Años , Artroplastia de Reemplazo , Arterias Cerebrales/diagnóstico por imagen , Estudios de Cohortes , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Columna Vertebral/cirugía
14.
Pharmacogenomics J ; 16(6): 551-558, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-26503817

RESUMEN

Gene copy number variants (CNVs) of CYP2E1 have been described but not functionally characterized. Here we investigated effects of CNVs on hepatic and lymphoblastoid CYP2E1 expression. Using available single-nuleotide polymorphism microarray data and quantitative PCR, CYP2E1 gene duplication and deletion carriers were identified. CYP2E1 mRNA, protein and enzyme activity (chlorzoxazone-6-hydroxylation) phenotypes of CYP2E1 were not associated with gene copy number. Analysis of gene expression in lymphoblastoid cell lines in relation to CNV confirmed this finding in an extrahepatic tissue and for other ethnicities. Further analyses identified a linked haplotype cluster with possible influence on gene expression. In summary, our data suggest a homeostatic, gene dosage-insensitive regulation of CYP2E1 expression by unknown gene dosage compensation mechanisms. This is in striking contrast to well-known structural variations of CYP2A6 and CYP2D6 that have a strong impact on expression and activity. These findings are important in the context of pharmacogenetic prediction.


Asunto(s)
Citocromo P-450 CYP2E1/genética , Citocromo P-450 CYP2E1/metabolismo , Variaciones en el Número de Copia de ADN , Dosificación de Gen , Hepatocitos/enzimología , Variantes Farmacogenómicas , Línea Celular , Clorzoxazona/metabolismo , Bases de Datos Genéticas , Eliminación de Gen , Duplicación de Gen , Perfilación de la Expresión Génica/métodos , Regulación Enzimológica de la Expresión Génica , Haplotipos , Humanos , Hidroxilación , Análisis de Secuencia por Matrices de Oligonucleótidos , Fenotipo , Reacción en Cadena de la Polimerasa , Polimorfismo de Nucleótido Simple , Población Blanca/genética
15.
Pharmacogenomics J ; 16(4): 341-51, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26239079

RESUMEN

Human organic anion transporter 7 (OAT7, SLC22A9) is a hepatic transport protein poorly characterized so far. We therefore sought to identify novel OAT7 substrates and factors contributing to variable hepatic OAT7 expression. Using OAT7-expressing cells, pravastatin was identified as a substrate. Hepatic SLC22A9/OAT7 mRNA and protein expression varied 28-fold and 15-fold, respectively, in 126 Caucasian liver samples. Twenty-four variants in SLC22A9 were genotyped, including three rare missense variants (rs377211288, rs61742518, rs146027075), which occurred only heterozygously. No variant significantly affected hepatic SLC22A9/OAT7 expression. The three missense variants, however, showed functional consequences when expressed in vitro. Hepatic nuclear factor 4-alpha (HNF4α) emerged as a major transcriptional regulator of SLC22A9 by a series of in silico and in vitro analyses. In conclusion, pravastatin is the first identified OAT7 drug substrate. Substantial inter-individual variability in hepatic OAT7 expression, majorly driven by HNF4α, may contribute to pravastatin drug disposition and might affect response.The Pharmacogenomics Journal advance online publication, 4 August 2015; doi:10.1038/tpj.2015.55.


Asunto(s)
Inhibidores de Hidroximetilglutaril-CoA Reductasas/metabolismo , Hígado/metabolismo , Transportadores de Anión Orgánico Sodio-Independiente/genética , Variantes Farmacogenómicas/genética , Pravastatina/metabolismo , Transporte Biológico , Regulación de la Expresión Génica , Células HEK293 , Factor Nuclear 4 del Hepatocito/genética , Factor Nuclear 4 del Hepatocito/metabolismo , Heterocigoto , Humanos , Cinética , Mutación Missense , Transportadores de Anión Orgánico Sodio-Independiente/metabolismo , Fenotipo , Transfección , Población Blanca/genética
16.
Diabetes Obes Metab ; 18(12): 1244-1252, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27502528

RESUMEN

AIMS: To evaluate, in patients with type 2 diabetes (T2DM) treated with insulin, the extent of weight gain over 2 years of insulin treatment, and the dynamics of weight gain in relation to glycaemic achievements over time according to adiposity levels at insulin initiation. MATERIALS AND METHODS: Patients with T2DM (n = 155 917), who commenced insulin therapy and continued it for at least 6 months, were selected from a large database of electronic medical records in the USA. Longitudinal changes in body weight and glycated haemoglobin (HbA1c) according to body mass index (BMI) category were estimated. RESULTS: Patients had a mean age of 59 years, a mean HbA1c level of 9.5%, and a mean BMI of 35 kg/m2 at insulin initiation. The HbA1c levels at insulin initiation were significantly lower (9.2-9.4%) in the obese patients than in patients with normal body weight (10.0%); however, the proportions of patients with HbA1c >7.5% or >8.0% were similar across the BMI categories. The adjusted weight gain fell progressively with increasing baseline BMI category over 6, 12 and 24 months (p < .01). The adjusted changes in HbA1c were similar across BMI categories. A 1% decrease in HbA1c was associated with progressively less weight gain as pretreatment BMI rose, ranging from a 1.24 kg gain in those with a BMI <25 kg/m2 to a 0.32 kg loss in those with a BMI > 40 kg/m2 . CONCLUSIONS: During 24 months of insulin treatment, obese patients gained significantly less body weight than normal-weight and overweight patients, while achieving clinically similar glycaemic benefits. These data provide reassurance with regard to the use of insulin in obese patients.


Asunto(s)
Diabetes Mellitus Tipo 2/tratamiento farmacológico , Hipoglucemiantes/uso terapéutico , Insulina/uso terapéutico , Obesidad Mórbida/metabolismo , Aumento de Peso , Anciano , Glucemia/metabolismo , Índice de Masa Corporal , Peso Corporal , Estudios de Casos y Controles , Bases de Datos Factuales , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/metabolismo , Registros Electrónicos de Salud , Femenino , Estudios de Seguimiento , Hemoglobina Glucada/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Obesidad/complicaciones , Obesidad/metabolismo , Obesidad Mórbida/complicaciones , Sobrepeso/complicaciones , Sobrepeso/metabolismo , Estudios Retrospectivos
17.
Exp Brain Res ; 234(9): 2609-18, 2016 09.
Artículo en Inglés | MEDLINE | ID: mdl-27173496

RESUMEN

In bipedal gait, the initiation of the first step is preceded by a complex sequence of movements which shift the centre of mass of the body towards the stance foot to allow for a step of the swing foot. These anticipatory postural adjustments (APAs) have been investigated in order to elucidate movement strategies in healthy and diseased persons. We studied the influence of several external parameters (age, type of step initiation) on APAs and investigated whether Parkinsonian patients may have different APAs. As a result, we found that externally elicited steps were preceded by faster and larger APAs than self-timed steps. Parkinsonian patients without the freezing of gait (FOG) phenomenon showed overall slightly reduced APAs but did not clearly differ from patients with FOG. Multiple APAs were seen in up to 25 % of the steps of the patients and in a much lower percentage of the steps of control subjects. The results indicate that APAs are significantly influenced by the timing of a step, i.e. are larger in externally elicited steps. The patients showed an overall preserved APA pattern but slowed movements and amplitude, indicating that increased bradykinesia due to progressive illness is a plausible explanation for these findings. The freezing phenomenon is not explained by a general absence or massive reduction in APA measures.


Asunto(s)
Trastornos Neurológicos de la Marcha/fisiopatología , Marcha/fisiología , Equilibrio Postural/fisiología , Adulto , Anciano , Fenómenos Biomecánicos , Femenino , Pie/fisiología , Pie/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , Movimiento/fisiología , Postura/fisiología , Tiempo de Reacción
18.
Acta Anaesthesiol Scand ; 60(4): 492-501, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26489399

RESUMEN

BACKGROUND: Perioperative high-dose oxygen (O2 ) exposure can cause hyperoxia. While the effect of constant hyperoxia on the vascular endothelium has been investigated to some extent, the impact of cyclic hyperoxia largely remains unknown. We hypothesized that cyclic hyperoxia would induce more injury than constant hyperoxia to human umbilical vein endothelial cells (HUVECs). METHODS: HUVECs were exposed to cyclic hyperoxia (5-95% O2 ) or constant hyperoxia (95% O2 ), normoxia (21% O2 ), and hypoxia (5% O2 ). Cell growth, viability (Annexin V/propidium iodide and 3-(4,5-dimethythiazol-2-yl)-2,5-diphenyl tetrazolium bromide, MTT) lactate dehydrogenase (LDH), release, cytokine (interleukin, IL and macrophage migration inhibitory factor, MIF) release, total antioxidant capacity (TAC), and superoxide dismutase activity (SOD) of cell lysate were assessed at baseline and 8, 24, and 72 h. A signal transduction pathway finder array for gene expression analysis was performed after 8 h. RESULTS: Constant and cyclic hyperoxia-induced gradually detrimental effects on HUVECs. After 72 h, constant or cyclic hyperoxia exposure induced change in cytotoxic (LDH +12%, P = 0.026; apoptosis +121/61%, P < 0.01; alive cells -15%, P < 0.01; MTT -16/15%, P < 0.01), inflammatory (IL-6 +142/190%, P < 0.01; IL-8 +72/43%, P < 0.01; MIF +147/93%, P < 0.01), or redox-sensitive (SOD +278%, TAC-25% P < 0.01) markers. Gene expression analysis revealed that constant and cyclic hyperoxia exposure differently activates oxidative stress, nuclear factor kappa B, Notch, and peroxisome proliferator-activated receptor pathways. CONCLUSIONS: Extreme hyperoxia exposure induces inflammation, apoptosis and cell death in HUVECs. Although our findings cannot be transferred to clinical settings, results suggest that hyperoxia exposure may cause vascular injury that could play a role in determining perioperative outcome.


Asunto(s)
Apoptosis , Hiperoxia/complicaciones , Inflamación/etiología , Proliferación Celular , Supervivencia Celular , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana/patología , Humanos , Hiperoxia/patología , Transcriptoma
19.
Nervenarzt ; 87(10): 1086-1093, 2016 Oct.
Artículo en Alemán | MEDLINE | ID: mdl-27389600

RESUMEN

Brivaracetam is the latest antiepileptic drug to be approved for adjunctive therapy in focal epilepsy and has a high affinity as a SV2A ligand. The aim of this review article is to summarize the data from the pivotal studies in which more than 2000 patients received brivaracetam. A significant median reduction in seizures from 30.5 % to 53.1 % for 50 mg/day, from 32.5 % to 37.2 % for 100 mg/day and 35.6 % for 200 mg/day could be demonstrated. Overall brivaracetam appears to be well-tolerated, with fatigue, dizziness and somnolence being the main adverse side effects. An immediate change from levetiracetam to brivaracetam at a conversion ratio of 10:1 to 15:1 seems feasible and could alleviate behavioral side effects related to treatment with levetiracetam. A swift permeability into brain tissue and a faster onset of action compared to levetiracetam suggest that brivaracetam could be useful in emergency situations.


Asunto(s)
Trastornos de Somnolencia Excesiva/inducido químicamente , Mareo/inducido químicamente , Epilepsias Parciales/tratamiento farmacológico , Fatiga/inducido químicamente , Pirrolidinonas/administración & dosificación , Pirrolidinonas/efectos adversos , Anticonvulsivantes/administración & dosificación , Anticonvulsivantes/efectos adversos , Quimioterapia Adyuvante , Trastornos de Somnolencia Excesiva/prevención & control , Mareo/prevención & control , Relación Dosis-Respuesta a Droga , Epilepsias Parciales/diagnóstico , Medicina Basada en la Evidencia , Fatiga/prevención & control , Humanos , Resultado del Tratamiento
20.
Clin Genet ; 87(6): 536-42, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25318681

RESUMEN

We identified an MSH6 mutation (c.10C>T, p.Gln4*) causing Lynch syndrome (LS) in 11 French Canadian (FC) families from the Canadian province of Quebec. We aimed to investigate the molecular and clinical implications of this mutation among FC carriers and to assess its putative founder origin. We studied 11 probands and 27 family members. Additionally 6433 newborns, 187 colorectal cancer (CRC) cases, 381 endometrial cancer (EC) cases and 179 additional controls, all of them from Quebec, were used. Found in approximately 1 of 400 newborns, the mutation is one of the most common LS mutations described. We have found that this mutation confers a greater risk for EC than for CRC, both in the 11 studied families and in the unselected cases: EC [odds ratio (OR) = 7.5, p < 0.0001] and CRC (OR = 2.2, p = 0.46). Haplotype analyses showed that the mutation arose in a common ancestor, probably around 430-656 years ago, coinciding with the arrival of the first French settlers. Application of the results of this study could significantly improve the molecular testing and clinical management of LS families in Quebec.


Asunto(s)
Neoplasias Colorrectales Hereditarias sin Poliposis/epidemiología , Neoplasias Colorrectales Hereditarias sin Poliposis/genética , Proteínas de Unión al ADN/genética , Etnicidad/genética , Efecto Fundador , Mutación , Adolescente , Adulto , Anciano , Canadá/epidemiología , Niño , Preescolar , Neoplasias Colorrectales Hereditarias sin Poliposis/diagnóstico , Neoplasias Endometriales/epidemiología , Neoplasias Endometriales/genética , Familia , Femenino , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Haplotipos , Heterocigoto , Humanos , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Quebec , Riesgo , Adulto Joven
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA