Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 471
Filtrar
Más filtros

Bases de datos
Tipo del documento
Intervalo de año de publicación
1.
MMWR Morb Mortal Wkly Rep ; 69(29): 965-970, 2020 Jul 24.
Artículo en Inglés | MEDLINE | ID: mdl-32701941

RESUMEN

Transmission of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), is ongoing in many communities throughout the United States. Although case-based and syndromic surveillance are critical for monitoring the pandemic, these systems rely on persons obtaining testing or reporting a COVID-19-like illness. Using serologic tests to detect the presence of SARS-CoV-2 antibodies is an adjunctive strategy that estimates the prevalence of past infection in a population. During April 28-May 3, 2020, coinciding with the end of a statewide shelter-in-place order, CDC and the Georgia Department of Public Health conducted a serologic survey in DeKalb and Fulton counties in metropolitan Atlanta to estimate SARS-CoV-2 seroprevalence in the population. A two-stage cluster sampling design was used to randomly select 30 census blocks in each county, with a target of seven participating households per census block. Weighted estimates were calculated to account for the probability of selection and adjusted for age group, sex, and race/ethnicity. A total of 394 households and 696 persons participated and had a serology result; 19 (2.7%) of 696 persons had SARS-CoV-2 antibodies detected. The estimated weighted seroprevalence across these two metropolitan Atlanta counties was 2.5% (95% confidence interval [CI] = 1.4-4.5). Non-Hispanic black participants more commonly had SARS-CoV-2 antibodies than did participants of other racial/ethnic groups (p<0.01). Among persons with SARS-CoV-2 antibodies, 13 (weighted % = 49.9; 95% CI = 24.4-75.5) reported a COVID-19-compatible illness,* six (weighted % = 28.2; 95% CI = 11.9-53.3) sought medical care for a COVID-19-compatible illness, and five (weighted % = 15.7; 95% CI = 5.1-39.4) had been tested for SARS-CoV-2 infection, demonstrating that many of these infections would not have been identified through case-based or syndromic surveillance. The relatively low seroprevalence estimate in this report indicates that most persons in the catchment area had not been infected with SARS-CoV-2 at the time of the survey. Continued preventive measures, including social distancing, consistent and correct use of face coverings, and hand hygiene, remain critical in controlling community spread of SARS-CoV-2.


Asunto(s)
Anticuerpos Antivirales/sangre , Betacoronavirus/inmunología , Técnicas de Laboratorio Clínico , Vigilancia en Salud Pública/métodos , Características de la Residencia/estadística & datos numéricos , Adolescente , Adulto , Anciano , Prueba de COVID-19 , Niño , Preescolar , Infecciones por Coronavirus/diagnóstico , Femenino , Georgia/epidemiología , Humanos , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , SARS-CoV-2 , Adulto Joven
2.
Br J Surg ; 106(4): 395-403, 2019 03.
Artículo en Inglés | MEDLINE | ID: mdl-30675910

RESUMEN

BACKGROUND: Percutaneous biopsy is recommended before surgery for suspected retroperitoneal sarcoma (RPS) to confirm the histological diagnosis and guide surgical strategy. The present study aimed to establish the diagnostic accuracy of percutaneous core biopsy with respect to histological diagnosis and tumour grade. METHODS: Data on patients with suspected RPS who underwent percutaneous biopsy followed by surgical resection between 2005 and 2016 at one of two tertiary European sarcoma units were reviewed. Histological tumour type and tumour grade on biopsy were correlated with postoperative histology to evaluate diagnostic accuracy. RESULTS: A total of 239 patients underwent percutaneous core biopsy followed by surgical resection in Milan (163, 68·2 per cent) or Birmingham (76, 31·8 per cent). Diagnostic accuracy varied with histological diagnosis (P < 0·001), but demonstrated overall concordance with final pathology following resection in 67·2 per cent of biopsies (κ = 0·606). The majority of discrepancies occurred in dedifferentiated liposarcoma (DDLPS), owing to under-recognition of dedifferentiation in this group. Concordance between pathology on biopsy and resection improved to 81·1 per cent when DDLPS and well differentiated liposarcoma were grouped together as liposarcoma. Grade on biopsy was concordant with grade on resection specimen in 60·4 per cent of tumours (κ = 0·640). Diagnosis of high-grade tumours on biopsy had a high specificity (98 per cent), and moderate positive predictive value (85 per cent) and negative predictive value (78 per cent). CONCLUSION: A diagnosis of DDLPS or leiomyosarcoma on percutaneous biopsy is highly reliable. High-grade sarcomas can be identified with high specificity, which opens the door to a study on neoadjuvant therapy in these patients.


Asunto(s)
Biopsia con Aguja Gruesa/métodos , Leiomiosarcoma/patología , Liposarcoma/patología , Liposarcoma/cirugía , Neoplasias Retroperitoneales/patología , Neoplasias Retroperitoneales/cirugía , Adulto , Anciano , Estudios de Cohortes , Bases de Datos Factuales , Supervivencia sin Enfermedad , Femenino , Hospitales Universitarios , Humanos , Italia , Leiomiosarcoma/mortalidad , Leiomiosarcoma/cirugía , Liposarcoma/mortalidad , Modelos Logísticos , Masculino , Persona de Mediana Edad , Pronóstico , Curva ROC , Neoplasias Retroperitoneales/mortalidad , Estudios Retrospectivos , Medición de Riesgo , Análisis de Supervivencia , Resultado del Tratamiento , Reino Unido
3.
Environ Geochem Health ; 41(2): 1037-1053, 2019 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30276587

RESUMEN

An assortment of organic material can leach from lignite (low-rank coal) in water, and the water-soluble fraction from lignite has been associated with adverse health effects in areas of the Balkans. Recent efforts have been made to evaluate this hypothesis in other areas where lignite is in contact with groundwater like in the U.S. Gulf Coast region. In this study, five Gulf Coast lignite samples were extracted with water, and the water-soluble portion of the coal was then characterized by total organic carbon, UV-Vis spectroscopy, and gas chromatography/mass spectrometry. Additionally, human kidney cells (HK-2) were exposed to water-soluble extracts of Gulf Coast lignite to assess toxicity. Cell viability was measured, and a dose-response curve was used to generate IC50 values that ranged from 490 to 3000 ppm. The most toxic extract (Dolet Hills) was from Louisiana where lignite-derived organic material has been previously linked to high incidence of renal pelvic cancer. Concentrations of nephrotoxic metals (As, Cd, Co, Cu, Hg, Pb, V, Zn) were screened and were below those considered toxic to renal cells. We conclude that leachates from lignite do indeed have toxic affects on cultured human renal cells. Although the IC50 values are higher than the concentration of organic matter in the local groundwater, typically < 5 ppm, the effects of long-term low-level exposure is not known.


Asunto(s)
Carbón Mineral/toxicidad , Riñón/efectos de los fármacos , Carbono/análisis , Línea Celular , Carbón Mineral/análisis , Cromatografía de Gases y Espectrometría de Masas , Humanos , Riñón/citología , Mercurio/análisis , Mercurio/toxicidad , Metales/análisis , Metales/toxicidad , Espectrofotometría Ultravioleta , Pruebas de Toxicidad/métodos , Estados Unidos , Agua/química
4.
Br J Surg ; 105(4): 401-409, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29405251

RESUMEN

BACKGROUND: Radiation-associated angiosarcoma of the breast (RAAS) is a rare complication of adjuvant radiotherapy associated with poor survival. The British Sarcoma Group guidelines recommend that all angiosarcomas are referred to a sarcoma multidisciplinary team, although there is no recommendation that patients are managed within a sarcoma service. The aims of this study were to compare survival, complete excision rates and local recurrence rates of patients managed within a sarcoma service and those managed within local hospitals. METHODS: All patients with RAAS referred to a regional sarcoma service between 1998 and 2015 were identified from prospective databases. Patient records, and radiology, pathology and operation notes were reviewed retrospectively. RESULTS: Thirty-six patients were operated on with curative intent; 26 were managed by the sarcoma service (of whom 21 underwent radical excision of the irradiated field followed by chest wall reconstruction) and ten were managed locally. Median age was 69·5 (range 43-85) years. Disease-specific survival was significantly longer in patients managed by the sarcoma service than in those managed locally: median 91·1 (range 69·2-113·0) versus 48·8 (18·6-79·1) months respectively (P = 0·012). Overall survival rates were similar (P = 0·112). There was no difference in complete excision rate (18 of 26 in sarcoma service versus 5 of 10 in local services; P = 0·456), although the local recurrence rate was significantly lower among patients managed by the sarcoma service (9 of 26 versus 8 of 10; P = 0·015). CONCLUSION: Specialist management of RAAS leads to fewer local recurrences and improved disease-specific survival. Early referral and management within specialist units is recommended.


Asunto(s)
Neoplasias de la Mama/mortalidad , Neoplasias de la Mama/cirugía , Hemangiosarcoma/mortalidad , Hemangiosarcoma/cirugía , Mastectomía , Neoplasias Inducidas por Radiación/mortalidad , Neoplasias Inducidas por Radiación/cirugía , Radioterapia Adyuvante/efectos adversos , Oncología Quirúrgica , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias de la Mama/etiología , Femenino , Estudios de Seguimiento , Hemangiosarcoma/etiología , Humanos , Persona de Mediana Edad , Recurrencia Local de Neoplasia/epidemiología , Neoplasias Inducidas por Radiación/etiología , Derivación y Consulta , Estudios Retrospectivos , Análisis de Supervivencia , Resultado del Tratamiento
6.
Artículo en Inglés | MEDLINE | ID: mdl-28739783

RESUMEN

Drug-drug interactions between antiretroviral medications and rifampin complicate the treatment of HIV and tuberculosis coinfection. This study evaluated the effect of rifampin on the pharmacokinetics of oral cabotegravir, an integrase strand transfer inhibitor being investigated for long-acting treatment and prevention of HIV-1 infection. This was a phase I, single-center, open-label, fixed-sequence crossover study in healthy adults. The objective was to evaluate the effect of steady-state rifampin on the single-dose plasma pharmacokinetics of cabotegravir. Subjects received a single oral dose of cabotegravir (30 mg) on day 1 followed by plasma sampling on days 1 to 8. Treatment with once-daily oral rifampin (600 mg) occurred on days 8 to 28. Subjects received a second dose of 30 mg cabotegravir on day 21 followed by pharmacokinetic sampling on days 21 to 28. Fifteen subjects were enrolled and completed the study. Rifampin decreased the cabotegravir area under the concentration-time curve from 0 h to infinity and the half-life by 59% and 57%, respectively, whereas oral clearance was increased 2.4-fold. The maximum concentration of cabotegravir in plasma was unaffected by coadministration with rifampin. All adverse events were mild in severity, with chromaturia attributed to rifampin observed in all subjects. Rifampin induction of cabotegravir metabolism resulted in increased cabotegravir oral clearance and significantly decreased cabotegravir exposures. Rifampin is expected to increase cabotegravir clearance following long-acting injectable administration. Concomitant administration of rifampin with oral and long-acting formulations of cabotegravir is not recommended currently without further study. (This study has been registered at ClinicalTrials.gov under registration no. NCT02411435.).


Asunto(s)
Fármacos Anti-VIH/sangre , Fármacos Anti-VIH/farmacocinética , Infecciones por VIH/prevención & control , Piridonas/sangre , Piridonas/farmacocinética , Rifampin/farmacología , Adulto , Anciano , Fármacos Anti-VIH/farmacología , Estudios Cruzados , Interacciones Farmacológicas , Femenino , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Voluntarios Sanos , Humanos , Masculino , Persona de Mediana Edad , Piridonas/farmacología , Adulto Joven
7.
Am J Physiol Regul Integr Comp Physiol ; 313(3): R240-R250, 2017 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-28637658

RESUMEN

Skeletal muscle stem cells play a critical role in regeneration of myofibers. We previously demonstrated that chronic binge alcohol (CBA) markedly attenuates myoblast differentiation potential and myogenic gene expression. Muscle-specific microRNAs (miRs) are implicated in regulation of myogenic genes. The aim of this study was to determine whether myoblasts isolated from asymptomatic CBA-administered simian immunodeficiency virus (SIV)-infected macaques treated with antiretroviral therapy (ART) showed similar impairments and, if so, to elucidate potential underlying mechanisms. Myoblasts were isolated from muscle at 11 mo after SIV infection from CBA/SIV macaques and from time-matched sucrose (SUC)-treated SIV-infected (SUC/SIV) animals and age-matched controls. Myoblast differentiation and myogenic gene expression were significantly decreased in myoblasts from SUC/SIV and CBA/SIV animals compared with controls. SIV and CBA decreased muscle-specific miR-206 in plasma and muscle and SIV decreased miR-206 expression in myoblasts, with no statistically significant changes in other muscle-specific miRs. These findings were associated with a significant increase in histone deacetylase 4 (HDAC4) and decrease in myogenic enhancer factor 2C (MEF2C) expression in CBA/SIV muscle. Transfection with miR-206 inhibitor decreased myotube differentiation, increased expression of HDAC4, and decreased MEF2C, suggesting a critical role of miR-206 in myogenesis. Moreover, HDAC4 was confirmed to be a direct miR-206 target. These results support a mechanistic role for decreased miR-206 in suppression of myoblast differentiation resulting from chronic alcohol and SIV infection. The parallel changes in skeletal muscle and circulating levels of miR-206 warrant studies to establish the possible use of plasma miR-206 as an indicator of impaired muscle function.


Asunto(s)
Consumo Excesivo de Bebidas Alcohólicas/fisiopatología , Diferenciación Celular , MicroARNs/metabolismo , Desarrollo de Músculos , Mioblastos/citología , Mioblastos/patología , Síndrome de Inmunodeficiencia Adquirida del Simio/fisiopatología , Animales , Consumo Excesivo de Bebidas Alcohólicas/patología , Consumo Excesivo de Bebidas Alcohólicas/virología , Regulación hacia Abajo , Macaca mulatta , Masculino , MicroARNs/genética , Mioblastos/virología , Síndrome de Inmunodeficiencia Adquirida del Simio/patología , Síndrome de Inmunodeficiencia Adquirida del Simio/virología
8.
Skin Res Technol ; 23(2): 221-226, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-27804169

RESUMEN

BACKGROUND: Recent advances in technology have enabled the development of various non-invasive skin imaging tools to aid real-time diagnosis of both benign and malignant skin tumours, minimizing the need for invasive skin biopsy. Multispectral optoacoustic tomography (MSOT) is a recently developed non-invasive imaging tool, which offers the unique capacity for high resolution three dimensional (3D) optical mapping of tissue by further delivering highly specific optical contrast from a depth of several millimetres to centimetres in living tissues. MSOT enables volumetric, spectroscopic differentiation of tissue, both in vivo and in real time, with and without the application of biomarker-specific probes, and is further able of providing spatial maps of skin chromophores, as well as underlying blood vasculature. METHODS: Three patients with suspicious skin tumours consented to have their lesions imaged with MSOT prior to excision. The histological findings and measurements were compared. RESULTS: We demonstrated the first in vivo clinical use of MSOT for 3D reconstruction of skin tumours in three patients with good histological correlation. CONCLUSION: Our findings confirm the potential benefit of the new imaging method in guiding surgical intervention to achieve a more precise excision with better clearance and lower relapse rates. It can also potentially help to shorten the duration of Mohs' micrographic surgery. Further large-scale studies are necessary to ensure correlation between MSOT and histology.


Asunto(s)
Interpretación de Imagen Asistida por Computador/métodos , Imagenología Tridimensional/métodos , Técnicas Fotoacústicas/métodos , Neoplasias Cutáneas/diagnóstico por imagen , Neoplasias Cutáneas/patología , Tomografía Óptica/métodos , Anciano , Dermoscopía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
9.
Int J Obes (Lond) ; 39(4): 695-701, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25354845

RESUMEN

BACKGROUND/OBJECTIVES: We have reported that maternal overnutrition/obesity (OB) in sheep resulting from feeding 150% of National Research Council (NRC) requirements throughout gestation leads to maternal hyperglycemia and hyperinsulinemia. Further, newborn lambs born to OB vs control-fed (CON, 100% of NRC) ewes exhibited greater adiposity, increased blood cortisol, insulin and glucose and the elimination of the postnatal leptin spike seen in lambs born to CON ewes. This early postnatal leptin peak is necessary for the development of hypothalamic circuits, which program appetite in later life. This study evaluated the multigenerational impact of OB on insulin:glucose dynamics of mature female F1 offspring fed only to requirements throughout gestation and on their lambs (F2 generation). DESIGN AND METHODS: Adult F1 female offspring born to OB (n=10) or CON (n=7) ewes were utilized. All F1 ewes were subjected to a glucose tolerance test at midgestation and late gestation. Jugular blood was obtained from F2 lambs at birth (day 1) through postnatal day 11, and plasma glucose, insulin, cortisol and leptin concentrations were determined. Dual-energy X-ray absorptiometry was utilized to determine bone mineral density, bone mineral content, lean tissue mass and fat tissue mass. RESULTS: Fasted blood glucose and insulin concentrations were greater (P<0.05) in OBF1 than CONF1 ewes at midgestation and late gestation. Further, after glucose infusion, both glucose and insulin concentrations remained higher in OBF1 ewes (P<0.05) than CONF1 ewes, demonstrating greater insulin resistance. Blood concentrations of glucose, insulin and cortisol and adiposity were higher (P<0.01) in OBF2 lambs than CONF2 lambs at birth. Importantly, OBF2 lambs failed to exhibit the early postnatal leptin peak exhibited by CONF2 lambs. CONCLUSIONS: These data suggest that these OBF2 lambs are predisposed to exhibit the same metabolic alterations as their mothers, suggesting a multigenerational programming effect.


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales/fisiología , Glucemia/metabolismo , Leptina/metabolismo , Obesidad/patología , Efectos Tardíos de la Exposición Prenatal/metabolismo , Alimentación Animal , Animales , Femenino , Prueba de Tolerancia a la Glucosa , Masculino , Desnutrición , Fenómenos Fisiologicos Nutricionales Maternos/fisiología , Hipernutrición , Embarazo , Ovinos
10.
Mol Genet Metab ; 115(1): 23-6, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25873073

RESUMEN

Dietary management of 418 adult patients with galactosaemia (from 39 centres/12 countries) was compared. All centres advised lactose restriction, 6 restricted galactose from galactosides ± fruits and vegetables and 12 offal. 38% (n=15) relaxed diet by: 1) allowing traces of lactose in manufactured foods (n=13) or 2) giving fruits, vegetables and galactosides (n=2). Only 15% (n=6) calculated dietary galactose. 32% of patients were lost to dietetic follow-up. In adult galactosaemia, there is limited diet relaxation.


Asunto(s)
Dieta , Galactosa/administración & dosificación , Galactosemias/dietoterapia , Adulto , Alimentos , Frutas , Humanos , Lactosa/administración & dosificación , Encuestas y Cuestionarios , Verduras
11.
Mol Genet Metab ; 115(1): 17-22, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25862610

RESUMEN

BACKGROUND: There appears little consensus concerning protein requirements in phenylketonuria (PKU). METHODS: A questionnaire completed by 63 European and Turkish IMD centres from 18 countries collected data on prescribed total protein intake (natural/intact protein and phenylalanine-free protein substitute [PS]) by age, administration frequency and method, monitoring, and type of protein substitute. Data were analysed by European region using descriptive statistics. RESULTS: The amount of total protein (from PS and natural/intact protein) varied according to the European region. Higher median amounts of total protein were prescribed in infants and children in Northern Europe (n=24 centres) (infants <1 year, >2-3g/kg/day; 1-3 years of age, >2-3 g/kg/day; 4-10 years of age, >1.5-2.5 g/kg/day) and Southern Europe (n=10 centres) (infants <1 year, 2.5 g/kg/day, 1-3 years of age, 2 g/kg/day; 4-10 years of age, 1.5-2 g/kg/day), than by Eastern Europe (n=4 centres) (infants <1 year, 2.5 g/kg/day, 1-3 years of age, >2-2.5 g/kg/day; 4-10 years of age, >1.5-2 g/kg/day) and with Western Europe (n=25 centres) giving the least (infants <1 year, >2-2.5 g/kg/day, 1-3 years of age, 1.5-2 g/kg/day; 4-10 years of age, 1-1.5 g/kg/day). Total protein prescription was similar in patients aged >10 years (1-1.5 g/kg/day) and maternal patients (1-1.5 g/kg/day). CONCLUSIONS: The amounts of total protein prescribed varied between European countries and appeared to be influenced by geographical region. In PKU, all gave higher than the recommended 2007 WHO/FAO/UNU safe levels of protein intake for the general population.


Asunto(s)
Aminoácidos/administración & dosificación , Caseínas/administración & dosificación , Proteínas en la Dieta/administración & dosificación , Suplementos Dietéticos , Fragmentos de Péptidos/administración & dosificación , Fenilcetonurias/dietoterapia , Adulto , Niño , Preescolar , Europa (Continente) , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Fenilalanina , Encuestas y Cuestionarios , Turquía , Organización Mundial de la Salud
12.
Intern Med J ; 45(10): 1054-65, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26247170

RESUMEN

BACKGROUND/AIM: This study aimed to report the clinical characteristics and outcomes of Australian patients treated with eculizumab for atypical haemolytic uraemic syndrome (aHUS). METHODS: A retrospective cohort study was undertaken of all patients in Australia treated with eculizumab provided in a compassionate access programme for a clinical diagnosis of aHUS using prospectively collected clinical data. RESULTS: A total of 10 patients with a median age of 23.5 years (interquartile range (IQR) 24.83 years) received compassionate access eculizumab for aHUS in Australia. Eight patients were female, and three had a family history of aHUS. Three received eculizumab for an initial acute aHUS presentation, three for relapsing and refractory acute aHUS, two for de novo aHUS post-renal transplantation, and one each for aHUS recurrence post-transplantation and facilitation of transplantation with a history of aHUS. The median duration of eculizumab therapy has been 911.5 days (IQR 569 days) with a cumulative exposure of 9184 days. At baseline all patients had renal and extra-renal aHUS involvement, with up to three non-renal organs affected. All but one patient, who died from uncontrollable gastrointestinal aHUS manifestations, have continued. The nine continuing patients achieved remission of aHUS. Two of the four patients requiring renal replacement therapy (RRT) at eculizumab commencement subsequently ceased RRT. Clinical events occurring in this cohort while on eculizumab treatment included neutropenia (two), posterior reversible encephalopathy syndrome (one), cardiomyopathy (one), pulmonary embolus (one), antibody-mediated rejection resulting in renal graft failure (one), iron deficiency (one), gastrointestinal haemorrhage (one) and death (one). CONCLUSION: Eculizumab has been an effective therapy for aHUS in this cohort, including when other therapies have failed.


Asunto(s)
Anticuerpos Monoclonales Humanizados/uso terapéutico , Síndrome Hemolítico Urémico Atípico/complicaciones , Síndrome Hemolítico Urémico Atípico/tratamiento farmacológico , Inactivadores del Complemento/uso terapéutico , Adolescente , Adulto , Anticuerpos Monoclonales Humanizados/efectos adversos , Australia , Ensayos de Uso Compasivo , Inactivadores del Complemento/efectos adversos , Femenino , Humanos , Lactante , Trasplante de Riñón , Masculino , Recurrencia , Estudios Retrospectivos , Resultado del Tratamiento , Adulto Joven
13.
Anaesthesia ; 70(2): 183-9, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25290190

RESUMEN

Animal studies have shown that injection pressures > 75 kPa indicate probable intrafascicular needle tip position. This study describes the flow/pressure characteristics of seven common needle systems. A syringe pump delivered flow rates of 5, 6.67, 10, 13.3, 15 and 20 ml.min(-1) through these needle systems, while keeping the needle tips open to atmosphere. A pressure transducer connected between the syringe and needle provided a real-time graphical display for analysis. Mean plateau pressures increased linearly with flow and with decreasing needle diameter (2.7-92 kPa). Flow rates > 17 ml.min(-1) and needle sizes 22 G and smaller produced mean plateau pressures > 75 kPa. Pressure monitors upstream from the needle may produce false-positive alarms at high flow rates due to needle resistance, and unreliable readings due to non-laminar flow. We recommend injection rates ≤ 15 ml.min(-1) (0.25 ml.s(-1) ) to reduce the effect of factors upstream from the needle tip as a cause of high pressure readings.


Asunto(s)
Anestesia de Conducción/instrumentación , Agujas/clasificación , Agujas/estadística & datos numéricos , Presión , Diseño de Equipo , Bombas de Infusión/estadística & datos numéricos , Inyecciones/instrumentación , Inyecciones/estadística & datos numéricos , Reología/métodos , Reología/estadística & datos numéricos , Jeringas/estadística & datos numéricos
14.
Br J Cancer ; 110(3): 648-55, 2014 Feb 04.
Artículo en Inglés | MEDLINE | ID: mdl-24335920

RESUMEN

BACKGROUND: Anti-EGFR antibody, cetuximab, improves overall survival (OS) in K-ras wild-type chemotherapy-refractory colorectal cancer. Epidermal growth factor receptor ligand epiregulin (EREG) gene expression may further predict cetuximab benefit. METHODS: Tumour samples from a phase III clinical trial of cetuximab plus best supportive care (BSC) vs BSC alone (CO.17) were analysed for EREG mRNA gene expression. Predictive effects of high vs low EREG on OS and progression-free survival (PFS) were examined for treatment-biomarker interaction. RESULTS: Both EREG and K-ras status were ascertained in 385 (193 cetuximab, 192 BSC) tumour samples. Within the high EREG and K-ras wild-type status ('co-biomarker')-positive group (n=139, 36%), median PFS was 5.4 vs 1.9 months (hazard ratio (HR) 0.31; P<0.0001), and median OS was 9.8 vs 5.1 months (HR 0.43; P<0.001) for cetuximab vs BSC, respectively. In the rest (n=246, 64%), PFS (HR 0.82; P=0.12) and OS (HR 0.90; P=0.45) were not significantly different. Test for treatment interaction showed a larger cetuximab effect on OS (HR 0.52; P=0.007) and PFS (HR 0.49; P=0.001) in the co-biomarker-positive group. CONCLUSION: In pre-treated K-ras wild-type status colorectal cancer, patients with high EREG gene expression appear to benefit more from cetuximab therapy compared with low expression. Epiregulin as a selective biomarker requires further evaluation.


Asunto(s)
Anticuerpos Monoclonales Humanizados/administración & dosificación , Neoplasias Colorrectales/tratamiento farmacológico , Factor de Crecimiento Epidérmico/biosíntesis , Proteínas ras/genética , Adulto , Anciano , Anciano de 80 o más Años , Biomarcadores de Tumor/genética , Cetuximab , Ensayos Clínicos Fase III como Asunto , Neoplasias Colorrectales/genética , Neoplasias Colorrectales/patología , Supervivencia sin Enfermedad , Factor de Crecimiento Epidérmico/genética , Epirregulina , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Mutación , Estadificación de Neoplasias
15.
Phys Rev Lett ; 113(1): 018301, 2014 Jul 04.
Artículo en Inglés | MEDLINE | ID: mdl-25032933

RESUMEN

In this Letter, we present NMR spin-lattice and relaxometry data for proton transfer in one of the shortest known N-H⋯O hydrogen bonds in a single crystal of 3,5 pyridinedicarboxylic acid (35PDCA). It is widely believed that proton transfer by quantum tunneling does not occur in short hydrogen bonds since the ground state energy level lies above the potential barrier, yet these data show a temperature independent, proton tunneling rate below 77 K and a clear deviation from classical dynamics below 91 K. This study therefore suggests that proton tunneling occurs in all hydrogen bonds at low temperature and the crossover temperature to classical hopping must be determined when evaluating whether proton tunneling persists at higher temperature, for example in enzyme catalysis under physiological conditions.

16.
Int J Obes (Lond) ; 37(4): 568-75, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22614057

RESUMEN

BACKGROUND: Obesity in women of childbearing age is increasing at an alarming rate. Growing evidence shows that maternal obesity induces detrimental effects on offspring health, including pre-disposition to obesity. We have shown that maternal obesity increases fetal intramuscular adipogenesis at mid-gestation. However, the mechanisms are poorly understood. MicroRNAs (miRNAs) regulate mRNA stability. We hypothesized that maternal obesity alters fetal muscle miRNA expression, thereby influencing intramuscular adipogenesis. METHODS: Non-pregnant ewes received a control diet (Con, fed 100% of National Research Council (NRC) recommendations, n=6) or obesogenic diet (OB; 150% NRC recommendations, n=6) from 60 days before to 75 days after conception when the fetal longissimus dorsi (LD) muscle was sampled and miRNA expression analyzed by miRNA microarray. One of miRNAs with differential expression between Con and OB fetal muscle, let-7g, was further tested for its role in adipogenesis and cell proliferation in C3H10T1/2 cells. RESULTS: A total of 155 miRNAs were found with a signal above 500, among which, three miRNAs, hsa-miR-381, hsa-let-7g and bta-miR-376d, were differentially expressed between Con and OB fetuses, and confirmed by quantitative real-time PCR (QRT-PCR) analyses. Reduced expression of miRNA let-7g, an abundantly expressed miRNA, in OB fetal muscle was correlated with higher expression of its target genes. Overexpression of let-7g in C3H10T1/2 cells reduced their proliferation rate. Expression of adipogenic markers decreased in cells overexpressing let-7g, and the formation of adipocytes was also reduced. Overexpression of let-7g decreased expression of inflammatory cytokines. CONCLUSION: Fetal muscle miRNA expression was altered due to maternal obesity, and let-7g downregulation may enhance intramuscular adipogenesis during fetal muscle development in the setting of maternal obesity.


Asunto(s)
Adipogénesis/genética , Desarrollo Fetal/genética , MicroARNs/metabolismo , Músculo Esquelético/metabolismo , Obesidad/metabolismo , Animales , Dieta , Regulación hacia Abajo , Femenino , Regulación del Desarrollo de la Expresión Génica , Fenómenos Fisiologicos Nutricionales Maternos , Músculo Esquelético/embriología , Obesidad/genética , Embarazo , Reacción en Cadena en Tiempo Real de la Polimerasa , Oveja Doméstica
17.
HIV Clin Trials ; 14(5): 192-203, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24144896

RESUMEN

BACKGROUND: GSK1265744 is an HIV integrase strand transfer inhibitor selected for clinical development. OBJECTIVE: This first-time-in-human and phase IIa investigation assessed GSK1265744 antiviral activity, pharmacokinetics, safety, and tolerability in healthy and HIV-1-infected subjects. METHODS: This double-blind, placebo-controlled study consisted of a dose escalation of single (part A) and multiple (part B) oral doses in 48 healthy subjects and an oral dose (part C) in 11 HIV-1-infected subjects. In part A, 2 cohorts of 9 subjects received either 5 and 25 mg or 10 and 50 mg. In part B, 3 cohorts of 10 subjects received 5, 10, or 25 mg once daily for 14 days. In part C and the phase IIa study, subjects received 5 or 30 mg once daily for 10 days. RESULTS: Dose-proportional increases in drug exposure were observed in healthy and HIV-1-infected subjects. In healthy subjects, pharmacokinetic variability was low following single or repeat dosing (coefficient of variation, 13%-34% and 15%-23%, respectively). Mean plasma half-life was 31.5 hours. GSK1265744 monotherapy significantly reduced plasma HIV-1 RNA from baseline to day 11 in HIV-1-infected subjects receiving 5 or 30 mg versus placebo (P < .001); mean decrease was 2.2 to 2.3 log10 copies/mL, respectively. Study drug was generally well tolerated with no clinically relevant trends in laboratory values, vital signs, or electrocardiograms. CONCLUSIONS: GSK1265744 was well tolerated in healthy and HIV-1-infected subjects. Results demonstrate once-daily doses of 5 or 30 mg exceeded minimum target therapeutic concentrations and produced a significant reduction in plasma HIV-1 RNA viral load.


Asunto(s)
Fármacos Anti-VIH/farmacocinética , Infecciones por VIH/tratamiento farmacológico , Piridonas/farmacocinética , Adulto , Fármacos Anti-VIH/efectos adversos , Fármacos Anti-VIH/uso terapéutico , Relación Dosis-Respuesta a Droga , Genotipo , VIH-1/genética , VIH-1/metabolismo , Humanos , Masculino , Piridonas/efectos adversos , Piridonas/uso terapéutico , ARN Viral , Carga Viral , Adulto Joven
18.
Photoacoustics ; 27: 100383, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36068806

RESUMEN

Combining optoacoustic (OA) imaging with ultrasound (US) enables visualisation of functional blood vasculature in breast lesions by OA to be overlaid with the morphological information of US. Here, we develop a simple OA feature set to differentiate benign and malignant breast lesions. 94 female patients with benign, indeterminate or suspicious lesions were recruited and underwent OA-US. An OA-US imaging feature set was developed using images from the first 38 patients, which contained 14 malignant and 8 benign solid lesions. Two independent radiologists blindly scored the OA-US images of a further 56 patients, which included 31 malignant and 13 benign solid lesions, with a sensitivity of 96.8% and specificity of 84.6%. Our findings indicate that OA-US can reveal vascular patterns of breast lesions that indicate malignancy using a simple feature set based on single wavelength OA data, which is therefore amenable to application in low resource settings for breast cancer management.

19.
Br J Cancer ; 105(1): 44-52, 2011 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-21629245

RESUMEN

BACKGROUND: The objectives of this phase I study were to determine the safety, pharmacokinetics (PK), pharmacodynamics and efficacy of brivanib combined with full-dose cetuximab in patients with advanced gastrointestinal malignancies. METHODS: Patients with advanced gastrointestinal malignancies who had failed prior therapies received brivanib (320, 600 or 800 mg daily) plus cetuximab (400 mg m(-2) loading dose then 250 mg m(-2) weekly). Assessments included adverse events, PK, tumour response, 2[18F]fluoro-2-deoxyglucose positron-emitting tomography and K-Ras mutation analyses. RESULTS: Toxicities observed were manageable; the most common treatment-related toxicities (>10% of patients) were fatigue, diarrhoea, anorexia, increase in aspartate aminotransferase and alanine aminotransferase, acneiform dermatitis, headache, mucosal inflammation, nausea, dry skin, vomiting, hypertension, pruritus, proteinuria and weight loss. Of 62 patients, 6 (9.7%) had objective radiographic partial responses, with an overall response rate of 10%. Median duration of response was 9.2 months; median progression-free survival was 3.9 months. CONCLUSIONS: The acceptable toxicity profile and efficacy of brivanib observed in this study were promising. These findings are being further evaluated in a phase III study of brivanib plus cetuximab vs cetuximab alone in patients previously treated with combination chemotherapy for K-Ras wild-type advanced metastatic colorectal cancer.


Asunto(s)
Alanina/análogos & derivados , Anticuerpos Monoclonales/farmacocinética , Anticuerpos Monoclonales/uso terapéutico , Neoplasias Gastrointestinales/tratamiento farmacológico , Terapia Recuperativa , Triazinas/farmacocinética , Triazinas/uso terapéutico , Adulto , Anciano , Alanina/farmacocinética , Alanina/uso terapéutico , Anticuerpos Monoclonales Humanizados , Antineoplásicos/farmacocinética , Antineoplásicos/uso terapéutico , Cetuximab , Quimioterapia Combinada , Femenino , Neoplasias Gastrointestinales/patología , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/tratamiento farmacológico , Recurrencia Local de Neoplasia/patología , Tasa de Supervivencia , Distribución Tisular , Resultado del Tratamiento , Receptor 2 de Factores de Crecimiento Endotelial Vascular/antagonistas & inhibidores
20.
Br J Cancer ; 104(3): 488-95, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21206494

RESUMEN

BACKGROUND: Although it is accepted that metastatic colorectal cancers (mCRCs) that carry activating mutations in KRAS are unresponsive to anti-epidermal growth factor receptor (EGFR) monoclonal antibodies, a significant fraction of KRAS wild-type (wt) mCRCs are also unresponsive to anti-EGFR therapy. Genes encoding EGFR ligands amphiregulin (AREG) and epiregulin (EREG) are promising gene expression-based markers but have not been incorporated into a test to dichotomise KRAS wt mCRC patients with respect to sensitivity to anti-EGFR treatment. METHODS: We used RT-PCR to test 110 candidate gene expression markers in primary tumours from 144 KRAS wt mCRC patients who received monotherapy with the anti-EGFR antibody cetuximab. Results were correlated with multiple clinical endpoints: disease control, objective response, and progression-free survival (PFS). RESULTS: Expression of many of the tested candidate genes, including EREG and AREG, strongly associate with all clinical endpoints. Using multivariate analysis with two-layer five-fold cross-validation, we constructed a four-gene predictive classifier. Strikingly, patients below the classifier cutpoint had PFS and disease control rates similar to those of patients with KRAS mutant mCRC. CONCLUSION: Gene expression appears to identify KRAS wt mCRC patients who receive little benefit from cetuximab. It will be important to test this model in an independent validation study.


Asunto(s)
Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Proteínas Proto-Oncogénicas/genética , Proteínas ras/genética , Anticuerpos Monoclonales/uso terapéutico , Anticuerpos Monoclonales Humanizados , Antineoplásicos/uso terapéutico , Cetuximab , Neoplasias Colorrectales/secundario , Resistencia a Antineoplásicos/genética , Expresión Génica , Humanos , Proteínas Proto-Oncogénicas p21(ras)
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA