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1.
Environ Sci Technol ; 57(17): 6799-6807, 2023 05 02.
Artículo en Inglés | MEDLINE | ID: mdl-37083047

RESUMEN

Plastic pollution has become ubiquitous with very high quantities detected even in ecosystems as remote as Arctic sea ice and deep-sea sediments. Ice algae growing underneath sea ice are released upon melting and can form fast-sinking aggregates. In this pilot study, we sampled and analyzed the ice algaeMelosira arcticaand ambient sea water from three locations in the Fram Strait to assess their microplastic content and potential as a temporary sink and pathway to the deep seafloor. Analysis by µ-Raman and fluorescence microscopy detected microplastics (≥2.2 µm) in all samples at concentrations ranging from 1.3 to 5.7 × 104 microplastics (MP) m-3 in ice algae and from 1.4 to 4.5 × 103 MP m-3 in sea water, indicating magnitude higher concentrations in algae. On average, 94% of the total microplastic particles were identified as 10 µm or smaller in size and comprised 16 polymer types without a clear dominance. The high concentrations of microplastics found in our pilot study suggest thatM. arctica could trap microplastics from melting ice and ambient sea water. The algae appear to be a temporary sink and could act as a key vector to food webs near the sea surface and on the deep seafloor, to which its fast-sinking aggregates could facilitate an important mechanism of transport.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos/análisis , Cadena Alimentaria , Ecosistema , Cubierta de Hielo , Proyectos Piloto , Regiones Árticas , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente
2.
Breast Cancer Res ; 24(1): 49, 2022 07 14.
Artículo en Inglés | MEDLINE | ID: mdl-35836268

RESUMEN

BACKGROUND: Early age at menarche and tall stature are associated with increased breast cancer risk. We examined whether these associations were also positively associated with mammographic density, a strong marker of breast cancer risk. METHODS: Participants were 10,681 breast-cancer-free women from 22 countries in the International Consortium of Mammographic Density, each with centrally assessed mammographic density and a common set of epidemiologic data. Study periods for the 27 studies ranged from 1987 to 2014. Multi-level linear regression models estimated changes in square-root per cent density (√PD) and dense area (√DA) associated with age at menarche and adult height in pooled analyses and population-specific meta-analyses. Models were adjusted for age at mammogram, body mass index, menopausal status, hormone therapy use, mammography view and type, mammographic density assessor, parity and height/age at menarche. RESULTS: In pooled analyses, later age at menarche was associated with higher per cent density (ß√PD = 0.023 SE = 0.008, P = 0.003) and larger dense area (ß√DA = 0.032 SE = 0.010, P = 0.002). Taller women had larger dense area (ß√DA = 0.069 SE = 0.028, P = 0.012) and higher per cent density (ß√PD = 0.044, SE = 0.023, P = 0.054), although the observed effect on per cent density depended upon the adjustment used for body size. Similar overall effect estimates were observed in meta-analyses across population groups. CONCLUSIONS: In one of the largest international studies to date, later age at menarche was positively associated with mammographic density. This is in contrast to its association with breast cancer risk, providing little evidence of mediation. Increased height was also positively associated with mammographic density, particularly dense area. These results suggest a complex relationship between growth and development, mammographic density and breast cancer risk. Future studies should evaluate the potential mediation of the breast cancer effects of taller stature through absolute breast density.


Asunto(s)
Densidad de la Mama , Neoplasias de la Mama , Adulto , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/etiología , Estudios Transversales , Femenino , Humanos , Mamografía/métodos , Menarquia , Grupos de Población , Embarazo , Factores de Riesgo
3.
Future Oncol ; 18(33): 3713-3726, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36250591

RESUMEN

Aim: Explore UK prostate cancer patients' experiences and preferences for in-person and remote consultations. Materials & methods: In January-March 2021, patients completed a survey of consultation format preferences. Results: Of 971 patients, most preferred in-person consultations when receiving diagnosis and results (92.3 and 66.5%, respectively) and discussing first and further treatment options (92.0 and 84.0%, respectively). Fewer patients considered follow-up (40.9%) or side effect consultations (47.7%) should be in person. Patients with longer travel preferred telephone consultations for receiving test results post-treatment. Patients over 55 preferred in-person consultations for discussing first treatment. Conclusion: To optimize prostate cancer care in the wake of COVID-19, we recommend patients have the option of consultation format, although key decisions should be made in person.


During the COVID-19 pandemic, there was a move away from in-person to remote consultations for patients with prostate cancer. However, it is not clear if remote consultations work well for every interaction. We surveyed UK-based men with prostate cancer about their preferences for consultation format. Patients wanted in-person consultations when receiving their diagnosis, discussing treatment options or getting test results after treatment. They were more accepting of remote consultations for regular follow-up or support with treatment side effects. Patients should ideally be offered a choice between in-person and remote consultations, although consultations should be in person when key decisions have to be made. These findings will be of value in planning care for patients with prostate cancer post pandemic.


Asunto(s)
COVID-19 , Neoplasias de la Próstata , Consulta Remota , Telemedicina , Masculino , Humanos , Consulta Remota/métodos , Telemedicina/métodos , Pandemias , Neoplasias de la Próstata/diagnóstico , Neoplasias de la Próstata/terapia , Reino Unido/epidemiología
4.
Int J Mol Sci ; 22(24)2021 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-34948015

RESUMEN

Mechanical cues play a vital role in limb skeletal development, yet their influence and underpinning mechanisms in the regulation of endochondral ossification (EO) processes are incompletely defined. Furthermore, interactions between endochondral growth and mechanics and the mTOR/NF-ĸB pathways are yet to be explored. An appreciation of how mechanical cues regulate EO would also clearly be beneficial in the context of fracture healing and bone diseases, where these processes are recapitulated. The study herein addresses the hypothesis that the mTOR/NF-ĸB pathways interact with mechanics to control endochondral growth. To test this, murine embryonic metatarsals were incubated ex vivo in a hydrogel, allowing for the effects of quasi-static loading on longitudinal growth to be assessed. The results showed significant restriction of metatarsal growth under quasi-static loading during a 14-day period and concentration-dependent sensitivity to hydrogel-related restriction. This study also showed that hydrogel-treated metatarsals retain their viability and do not present with increased apoptosis. Metatarsals exhibited reversal of the growth-restriction when co-incubated with mTOR compounds, whilst it was found that these compounds showed no effects under basal culture conditions. Transcriptional changes linked to endochondral growth were assessed and downregulation of Col2 and Acan was observed in hydrogel-treated metatarsi at day 7. Furthermore, cell cycle analyses confirmed the presence of chondrocytes exhibiting S-G2/M arrest. These data indicate that quasi-static load provokes chondrocyte cell cycle arrest, which is partly overcome by mTOR, with a less marked interaction for NF-ĸB regulators.


Asunto(s)
Huesos Metatarsianos/embriología , Huesos Metatarsianos/crecimiento & desarrollo , FN-kappa B/metabolismo , Técnicas de Cultivo de Órganos/métodos , Agrecanos/genética , Animales , Fenómenos Biomecánicos , Colágeno Tipo II/genética , Medios de Cultivo , Perfilación de la Expresión Génica , Regulación del Desarrollo de la Expresión Génica , Hidrogeles , Huesos Metatarsianos/metabolismo , Ratones , Ratones Endogámicos C57BL , Transducción de Señal , Serina-Treonina Quinasas TOR/metabolismo
5.
Diabetologia ; 63(10): 2205-2217, 2020 10.
Artículo en Inglés | MEDLINE | ID: mdl-32728894

RESUMEN

AIMS/HYPOTHESIS: Treatment of vascular complications of diabetes remains inadequate. We reported that muscle pericytes (MPs) from limb muscles of vascular patients with diabetes mellitus display elevated levels of oxidative stress causing a dysfunctional phenotype. Here, we investigated whether treatment with dimethyl-2-oxoglutarate (DM-2OG), a tricarboxylic acid cycle metabolite with antioxidant properties, can restore a healthy metabolic and functional phenotype. METHODS: MPs were isolated from limb muscles of diabetes patients with vascular disease (D-MPs) and from non-diabetic control participants (ND-MPs). Metabolic status was assessed in untreated and DM-2OG-treated (1 mmol/l) cells using an extracellular flux analyser and anion-exchange chromatography-mass spectrometry (IC-MS/MS). Redox status was measured using commercial kits and IC-MS/MS, with antioxidant and metabolic enzyme expression assessed by quantitative RT-PCR and western blotting. Myogenic differentiation and proliferation and pericyte-endothelial interaction were assessed as functional readouts. RESULTS: D-MPs showed mitochondrial dysfunction, suppressed glycolytic activity and reduced reactive oxygen species-buffering capacity, but no suppression of antioxidant systems when compared with ND-MP controls. DM-2OG supplementation improved redox balance and mitochondrial function, without affecting glycolysis or antioxidant systems. Nonetheless, this was not enough for treated D-MPs to regain the level of proliferation and myogenic differentiation of ND-MPs. Interestingly, DM-2OG exerted a positive effect on pericyte-endothelial cell interaction in the co-culture angiogenesis assay, independent of the diabetic status. CONCLUSIONS/INTERPRETATION: These novel findings support the concept of using DM-2OG supplementation to improve pericyte redox balance and mitochondrial function, while concurrently allowing for enhanced pericyte-endothelial crosstalk. Such effects may help to prevent or slow down vasculopathy in skeletal muscles of people with diabetes. Graphical abstract.


Asunto(s)
Diabetes Mellitus Tipo 1/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Ácidos Cetoglutáricos/farmacología , Mitocondrias/efectos de los fármacos , Oxidación-Reducción/efectos de los fármacos , Pericitos/efectos de los fármacos , Adulto , Estudios de Casos y Controles , Técnicas de Cultivo de Célula , Femenino , Glucólisis/efectos de los fármacos , Humanos , Isquemia/metabolismo , Masculino , Persona de Mediana Edad , Mitocondrias/metabolismo , Músculo Esquelético/citología , Músculo Esquelético/metabolismo , Pericitos/metabolismo , Enfermedades Vasculares Periféricas/metabolismo , Especies Reactivas de Oxígeno/metabolismo
6.
Genesis ; 57(11-12): e23339, 2019 11.
Artículo en Inglés | MEDLINE | ID: mdl-31724301

RESUMEN

This study was conducted to check whether the three chick Early B-cell Factor (Ebf) genes, particularly cEbf1, would be targets for Shh and Bmp signals during somites mediolateral (ML) patterning. Tissue manipulations and gain and loss of function experiments for Shh and Bmp4 were performed and the results revealed that cEbf1 expression was initiated in the cranial presomitic mesoderm by low dose of Bmp4 from the lateral mesoderm and maintained in the ventromedial part of the epithelial somite and the medial sclerotome by Shh from the notochord; while cEbf2/3 expression was induced and maintained by Bmp4 and inhibited by high dose of Shh. To determine whether Ebf1 plays a role in somite patterning, transfection of a dominant-negative construct was carried out; this showed suppression of cPax1 expression in the medial sclerotome and upregulation and medial expansion of cEbf3 and cPax3 expression in sclerotome and dermomyotome, respectively, suggesting that Ebf1 is important for ML patterning. Thus, it is possible that low doses of Bmp4 set up Ebf1 expression which, together with Shh from the notochord, leads to establishment of the medial sclerotome and suppression of lateral identities. These data also conclude that Bmp4 is required in both the medial and lateral domain of the somitic mesoderm to keep the ML identity of the sclerotome through maintenance of cEbf gene expression. These striking findings are novel and give a new insight on the role of Bmp4 on mediolateral patterning of somites.


Asunto(s)
Tipificación del Cuerpo/genética , Transactivadores/genética , Animales , Proteína Morfogenética Ósea 4/metabolismo , Embrión de Pollo , Pollos/metabolismo , Regulación del Desarrollo de la Expresión Génica/genética , Proteínas Hedgehog/genética , Mesodermo/metabolismo , Notocorda/metabolismo , Somitos/metabolismo , Factores de Transcripción/genética
7.
Exp Cell Res ; 364(1): 16-27, 2018 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-29360432

RESUMEN

This study demonstrates highly dynamic spatial and temporal pattern of SULF1/SULF2 expression in a number of neuronal cell types growing in normal culture medium that included their transient nuclear mobilisation. Their nuclear translocation became particularly apparent during cell proliferation as both SULF1/SULF2 demonstrated not only cell membrane associated expression, their known site of function but also transient nuclear mobilisation during nuclear cell division. Nuclear localisation was apparent not only by immunocytochemical staining but also confirmed by immunoblotting staining of isolated nuclear fractions of C6, U87 and N2A cells. Immunocytochemical analysis demonstrated rapid nuclear exit of both SULF1/SULF2 following cell division that was slightly delayed but not blocked in a fraction of the polyploid cells observed in C6 cells. The overexpression of both Sulf1 and Sulf2 genes in C6 and U87 cells markedly promoted in vitro growth of these cells accompanied by nuclear mobilisation while inhibition of both these genes inhibited cell proliferation with little or no nuclear SULF1/SULF2 mobilisation. SULF1/SULF2 activity in these cells thus demonstrated a clear co-ordination of extracellular cell signalling with nuclear events related to cell proliferation.


Asunto(s)
Ciclo Celular , Núcleo Celular/metabolismo , Matriz Extracelular/metabolismo , Glioma/metabolismo , Neuroblastoma/metabolismo , Sulfotransferasas/metabolismo , Núcleo Celular/genética , Células Cultivadas , Glioma/patología , Humanos , Neuroblastoma/patología , Neuronas/citología , Neuronas/metabolismo , Transducción de Señal , Sulfatasas
8.
Breast Cancer Res ; 20(1): 156, 2018 12 29.
Artículo en Inglés | MEDLINE | ID: mdl-30594212

RESUMEN

BACKGROUND: Fully automated assessment of mammographic density (MD), a biomarker of breast cancer risk, is being increasingly performed in screening settings. However, data on body mass index (BMI), a confounder of the MD-risk association, are not routinely collected at screening. We investigated whether the amount of fat in the breast, as captured by the amount of mammographic non-dense tissue seen on the mammographic image, can be used as a proxy for BMI when data on the latter are unavailable. METHODS: Data from a UK case control study (numbers of cases/controls: 414/685) and a Norwegian cohort study (numbers of cases/non-cases: 657/61059), both with volumetric MD measurements (dense volume (DV), non-dense volume (NDV) and percent density (%MD)) from screening-age women, were analysed. BMI (self-reported) and NDV were taken as measures of adiposity. Correlations between BMI and NDV, %MD and DV were examined after log-transformation and adjustment for age, menopausal status and parity. Logistic regression models were fitted to the UK study, and Cox regression models to the Norwegian study, to assess associations between MD and breast cancer risk, expressed as odds/hazard ratios per adjusted standard deviation (OPERA). Adjustments were first made for standard risk factors except BMI (minimally adjusted models) and then also for BMI or NDV. OPERA pooled relative risks (RRs) were estimated by fixed-effect models, and between-study heterogeneity was assessed by the I2 statistics. RESULTS: BMI was positively correlated with NDV (adjusted r = 0.74 in the UK study and r = 0.72 in the Norwegian study) and with DV (r = 0.33 and r = 0.25, respectively). Both %MD and DV were positively associated with breast cancer risk in minimally adjusted models (pooled OPERA RR (95% confidence interval): 1.34 (1.25, 1.43) and 1.46 (1.36, 1.56), respectively; I2 = 0%, P >0.48 for both). Further adjustment for BMI or NDV strengthened the %MD-risk association (1.51 (1.41, 1.61); I2 = 0%, P = 0.33 and 1.51 (1.41, 1.61); I2 = 0%, P = 0.32, respectively). Adjusting for BMI or NDV marginally affected the magnitude of the DV-risk association (1.44 (1.34, 1.54); I2 = 0%, P = 0.87 and 1.49 (1.40, 1.60); I2 = 0%, P = 0.36, respectively). CONCLUSIONS: When volumetric MD-breast cancer risk associations are investigated, NDV can be used as a measure of adiposity when BMI data are unavailable.


Asunto(s)
Índice de Masa Corporal , Densidad de la Mama , Neoplasias de la Mama/diagnóstico por imagen , Procesamiento de Imagen Asistido por Computador/métodos , Mamografía/métodos , Adiposidad , Anciano , Anciano de 80 o más Años , Mama/diagnóstico por imagen , Mama/patología , Neoplasias de la Mama/patología , Estudios de Casos y Controles , Estudios de Cohortes , Estudios de Factibilidad , Femenino , Humanos , Modelos Logísticos , Tamizaje Masivo/métodos , Persona de Mediana Edad , Noruega , Medición de Riesgo , Factores de Riesgo , Reino Unido
9.
Reproduction ; 156(4): 313-330, 2018 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-30306765

RESUMEN

Equine chorionic girdle trophoblast cells play important endocrine and immune functions critical in supporting pregnancy. Very little is known about the genes and pathways that regulate chorionic girdle trophoblast development. Our aim was to identify genes and signalling pathways active in vivo in equine chorionic girdle trophoblast within a critical 7-days window. We exploited the late implantation of the equine conceptus to obtain trophoblast tissue. An Agilent equine 44K microarray was performed using RNA extracted from chorionic girdle and chorion (control) from equine pregnancy days 27, 30, 31 and 34 (n = 5), corresponding to the initiation of chorionic girdle trophoblast proliferation, differentiation and migration. Data were analysed using R packages limma and maSigPro, Ingenuity Pathway Analysis and DAVID and verified using qRT-PCR, promoter analysis, western blotting and migration assays. Microarray analysis showed gene expression (absolute log FC >2, FDR-adjusted P < 0.05) was rapidly and specifically induced in the chorionic girdle between days 27 and 34 (compared to day 27, day 30 = 116, day 31 = 317, day 34 = 781 genes). Pathway analysis identified 35 pathways modulated during chorionic girdle development (e.g. FGF, integrin, Rho GTPases, MAPK) including pathways that have limited description in mammalian trophoblast (e.g. IL-9, CD40 and CD28 signalling). Rho A and ERK/MAPK activity was confirmed as was a role for transcription factor ELF5 in regulation of the CGB promoter. The purity and accessibility of chorionic girdle trophoblast proved to be a powerful resource to identify candidate genes and pathways involved in early equine placental development.


Asunto(s)
Caballos/embriología , Trofoblastos/metabolismo , Animales , Femenino , Expresión Génica , Caballos/metabolismo , Masculino , Placentación , Embarazo , Transducción de Señal , Transcriptoma
10.
PLoS Med ; 14(6): e1002335, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28666001

RESUMEN

BACKGROUND: Mammographic density (MD) is one of the strongest breast cancer risk factors. Its age-related characteristics have been studied in women in western countries, but whether these associations apply to women worldwide is not known. METHODS AND FINDINGS: We examined cross-sectional differences in MD by age and menopausal status in over 11,000 breast-cancer-free women aged 35-85 years, from 40 ethnicity- and location-specific population groups across 22 countries in the International Consortium on Mammographic Density (ICMD). MD was read centrally using a quantitative method (Cumulus) and its square-root metrics were analysed using meta-analysis of group-level estimates and linear regression models of pooled data, adjusted for body mass index, reproductive factors, mammogram view, image type, and reader. In all, 4,534 women were premenopausal, and 6,481 postmenopausal, at the time of mammography. A large age-adjusted difference in percent MD (PD) between post- and premenopausal women was apparent (-0.46 cm [95% CI: -0.53, -0.39]) and appeared greater in women with lower breast cancer risk profiles; variation across population groups due to heterogeneity (I2) was 16.5%. Among premenopausal women, the √PD difference per 10-year increase in age was -0.24 cm (95% CI: -0.34, -0.14; I2 = 30%), reflecting a compositional change (lower dense area and higher non-dense area, with no difference in breast area). In postmenopausal women, the corresponding difference in √PD (-0.38 cm [95% CI: -0.44, -0.33]; I2 = 30%) was additionally driven by increasing breast area. The study is limited by different mammography systems and its cross-sectional rather than longitudinal nature. CONCLUSIONS: Declines in MD with increasing age are present premenopausally, continue postmenopausally, and are most pronounced over the menopausal transition. These effects were highly consistent across diverse groups of women worldwide, suggesting that they result from an intrinsic biological, likely hormonal, mechanism common to women. If cumulative breast density is a key determinant of breast cancer risk, younger ages may be the more critical periods for lifestyle modifications aimed at breast density and breast cancer risk reduction.


Asunto(s)
Envejecimiento , Densidad de la Mama , Perimenopausia , Posmenopausia , Premenopausia , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Persona de Mediana Edad
11.
J Cell Physiol ; 231(6): 1392-404, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26639105

RESUMEN

The transmembrane glycoprotein E11 is considered critical in early osteoblast-osteocyte transitions (osteocytogenesis), however its function and regulatory mechanisms are still unknown. Using the late osteoblast MLO-A5 cell line we reveal increased E11 protein/mRNA expression (P < 0.001) concomitant with extensive osteocyte dendrite formation and matrix mineralization (P < 0.001). Transfection with E11 significantly increased mRNA levels (P < 0.001), but immunoblotting failed to detect any correlative increases in E11 protein levels, suggestive of post-translational degradation. We found that exogenous treatment of MLO-A5 and osteocytic IDG-SW3 cells with 10 µM ALLN (calpain and proteasome inhibitor) stabilized E11 protein levels and induced a profound increase in osteocytic dendrite formation (P < 0.001). Treatment with other calpain inhibitors failed to promote similar osteocytogenic changes, suggesting that these effects of ALLN rely upon its proteasome inhibitor actions. Accordingly we found that proteasome-selective inhibitors (MG132/lactacystin/ Bortezomib/Withaferin-A) produced similar dose-dependent increases in E11 protein levels in MLO-A5 and primary osteoblast cells. This proteasomal targeting was confirmed by immunoprecipitation of ubiquitinylated proteins, which included E11, and by increased levels of ubiquitinylated E11 protein upon addition of the proteasome inhibitors MG132/Bortezomib. Activation of RhoA, the small GTPase, was found to be increased concomitant with the peak in E11 levels and its downstream signaling was also observed to promote MLO-A5 cell dendrite formation. Our data indicate that a mechanism reliant upon blockade of proteasome-mediated E11 destabilization contributes to osteocytogenesis and that this may involve downstream targeting of RhoA. This work adds to our mechanistic understanding of the factors regulating bone homeostasis, which may lead to future therapeutic approaches.


Asunto(s)
Diferenciación Celular/efectos de los fármacos , Glicoproteínas de Membrana/metabolismo , Osteoblastos/efectos de los fármacos , Osteocitos/efectos de los fármacos , Complejo de la Endopetidasa Proteasomal/metabolismo , Inhibidores de Proteasoma/farmacología , Animales , Calpaína/antagonistas & inhibidores , Calpaína/metabolismo , Línea Celular , Inhibidores de Cisteína Proteinasa/farmacología , Relación Dosis-Respuesta a Droga , Glicoproteínas de Membrana/genética , Ratones Endogámicos C57BL , Osteoblastos/enzimología , Osteocitos/enzimología , Fenotipo , Estabilidad Proteica , Proteolisis , ARN Mensajero/metabolismo , Factores de Tiempo , Transfección , Ubiquitinación , Proteínas de Unión al GTP rho/metabolismo , Proteína de Unión al GTP rhoA
12.
Breast Cancer Res ; 18(1): 96, 2016 09 26.
Artículo en Inglés | MEDLINE | ID: mdl-27670914

RESUMEN

BACKGROUND: Full-field digital mammography, which is gradually being introduced in most clinical and screening settings, produces two types of images: raw and processed. However, the extent to which mammographic density measurements, and their ability to predict breast cancer risk, vary according to type of image is not fully known. METHODS: We compared the performance of the semi-automated Cumulus method on digital raw, "analogue-like" raw and processed images, and the performance of a recently developed method - Laboratory for Breast Radiodensity Assessment (LIBRA) - on digital raw and processed images, in a case-control study (414 patients (cases) and 684 controls) by evaluating the extent to which their measurements were associated with breast cancer risk factors, and by comparing their ability to predict breast cancer risk. RESULTS: Valid Cumulus and LIBRA measurements were obtained from all available images, but the resulting distributions differed according to the method and type of image used. Both Cumulus and LIBRA percent density were inversely associated with age, body mass index (BMI), parity and postmenopausal status, regardless of type of image used. Cumulus percent density was strongly associated with breast cancer risk, but with the magnitude of the association slightly stronger for processed (risk increase per one SD increase in percent density (95 % CI): 1.55 (1.29, 1.85)) and "analogue-like" raw (1.52 (1.28, 1.80)) than for raw (1.35 (1.14, 1.60)) images. LIBRA percent density produced weaker associations with risk, albeit stronger for processed (1.32 (1.08, 1.61)) than raw images (1.17 (0.99, 1.37)). The percent density values yielded by the various density assessment/type of image combinations had similar ability to discriminate between patients and controls (area under the receiving operating curve values for percent density, age, BMI, parity and menopausal status combined ranged from 0.61 and 0.64). CONCLUSIONS: The findings showed that Cumulus can be used to measure density on all types of digital images. They also indicate that LIBRA may provide a valid fully automated alternative to the more labour-intensive Cumulus. However, the same digital image type and assessment method should be used when examining mammographic density across populations, or longitudinal changes in density within a single population.


Asunto(s)
Densidad de la Mama , Neoplasias de la Mama/epidemiología , Neoplasias de la Mama/patología , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Mamografía/métodos , Persona de Mediana Edad , Oportunidad Relativa , Medición de Riesgo , Factores de Riesgo
13.
Breast Cancer Res ; 18(1): 130, 2016 12 19.
Artículo en Inglés | MEDLINE | ID: mdl-27993168

RESUMEN

BACKGROUND: Inter-women and intra-women comparisons of mammographic density (MD) are needed in research, clinical and screening applications; however, MD measurements are influenced by mammography modality (screen film/digital) and digital image format (raw/processed). We aimed to examine differences in MD assessed on these image types. METHODS: We obtained 1294 pairs of images saved in both raw and processed formats from Hologic and General Electric (GE) direct digital systems and a Fuji computed radiography (CR) system, and 128 screen-film and processed CR-digital pairs from consecutive screening rounds. Four readers performed Cumulus-based MD measurements (n = 3441), with each image pair read by the same reader. Multi-level models of square-root percent MD were fitted, with a random intercept for woman, to estimate processed-raw MD differences. RESULTS: Breast area did not differ in processed images compared with that in raw images, but the percent MD was higher, due to a larger dense area (median 28.5 and 25.4 cm2 respectively, mean √dense area difference 0.44 cm (95% CI: 0.36, 0.52)). This difference in √dense area was significant for direct digital systems (Hologic 0.50 cm (95% CI: 0.39, 0.61), GE 0.56 cm (95% CI: 0.42, 0.69)) but not for Fuji CR (0.06 cm (95% CI: -0.10, 0.23)). Additionally, within each system, reader-specific differences varied in magnitude and direction (p < 0.001). Conversion equations revealed differences converged to zero with increasing dense area. MD differences between screen-film and processed digital on the subsequent screening round were consistent with expected time-related MD declines. CONCLUSIONS: MD was slightly higher when measured on processed than on raw direct digital mammograms. Comparisons of MD on these image formats should ideally control for this non-constant and reader-specific difference.


Asunto(s)
Densidad de la Mama , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/patología , Procesamiento de Imagen Asistido por Computador , Mamografía/métodos , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Persona de Mediana Edad
14.
J Surg Res ; 206(2): 411-417, 2016 12.
Artículo en Inglés | MEDLINE | ID: mdl-27884337

RESUMEN

BACKGROUND: Fostering surgeon engagement in community outreach was recently identified as a major priority toward reducing health care disparities in surgery. We aimed to increase surgeon engagement in the local community, understand prevalent beliefs, and identify educational opportunities in the local community regarding cancer screening and treatment using community outreach. MATERIALS AND METHODS: In collaboration with the university's cancer center, the medical student surgical interest group, surgical faculty, and residents developed a community outreach program. The program consisted of networking time, a formal presentation, panel discussion, and question and answer time. A survey was distributed to all participants before the educational session, and a program assessment was distributed at the program's conclusion. RESULTS: A total of 256 community members and 22 surgical volunteers attended at least one of the two events. Attendees were insured (175; 92.7%), female (151; 80%), and African-American (176; 93.1%), with a mean age of 61 y (standard deviation 14.0). About 56 participants (29.6%) were unwilling to undergo screening colonoscopy. Forty-eight respondents (25.4%) endorsed mistrust in doctors and 25% believed surgery causes cancer to spread; a significantly higher proportion of them aged <60 y old. About 113 (59.8%) and 87 (46.1%) misunderstood the definitions of malignant and metastatic, respectively. Males were more unsure than females (61% versus 55%, P = 0.5 and 70% versus 55%; P = 0.01). CONCLUSIONS: Risk perceptions related to fatalism, mistrust, or lack of knowledge were prevalent. The ability of surgeons to reach at-risk populations in the prehospital setting is an important opportunity waiting to be capitalized upon.


Asunto(s)
Actitud Frente a la Salud , Relaciones Comunidad-Institución , Educación en Salud/métodos , Hospitales Universitarios , Relaciones Médico-Paciente , Cirujanos , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Colonoscopía , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/cirugía , Femenino , Educación en Salud/organización & administración , Disparidades en Atención de Salud , Humanos , Masculino , Persona de Mediana Edad , Philadelphia , Estudiantes de Medicina , Confianza , Adulto Joven
15.
Emerg Infect Dis ; 21(7): 1128-34, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26079176

RESUMEN

In May 2014, a traveler from the Kingdom of Saudi Arabia was the first person identified with Middle East respiratory syndrome coronavirus (MERS-CoV) infection in the United States. To evaluate transmission risk, we determined the type, duration, and frequency of patient contact among health care personnel (HCP), household, and community contacts by using standard questionnaires and, for HCP, global positioning system (GPS) tracer tag logs. Respiratory and serum samples from all contacts were tested for MERS-CoV. Of 61 identified contacts, 56 were interviewed. HCP exposures occurred most frequently in the emergency department (69%) and among nurses (47%); some HCP had contact with respiratory secretions. Household and community contacts had brief contact (e.g., hugging). All laboratory test results were negative for MERS-CoV. This contact investigation found no secondary cases, despite case-patient contact by 61 persons, and provides useful information about MERS-CoV transmission risk. Compared with GPS tracer tag recordings, self-reported contact may not be as accurate.


Asunto(s)
Infecciones por Coronavirus/transmisión , Coronavirus del Síndrome Respiratorio de Oriente Medio , Adulto , Trazado de Contacto , Infecciones por Coronavirus/virología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Medición de Riesgo , Estados Unidos , Adulto Joven
16.
Breast Cancer Res ; 16(5): 439, 2014 Sep 20.
Artículo en Inglés | MEDLINE | ID: mdl-25239205

RESUMEN

INTRODUCTION: Mammographic density is a strong breast cancer risk factor and a major determinant of screening sensitivity. However, there is currently no validated estimation method for full-field digital mammography (FFDM). METHODS: The performance of three area-based approaches (BI-RADS, the semi-automated Cumulus, and the fully-automated ImageJ-based approach) and three fully-automated volumetric methods (Volpara, Quantra and single energy x-ray absorptiometry (SXA)) were assessed in 3168 FFDM images from 414 cases and 685 controls. Linear regression models were used to assess associations between breast cancer risk factors and density among controls, and logistic regression models to assess density-breast cancer risk associations, adjusting for age, body mass index (BMI) and reproductive variables. RESULTS: Quantra and the ImageJ-based approach failed to produce readings for 4% and 11% of the participants. All six density assessment methods showed that percent density (PD) was inversely associated with age, BMI, being parous and postmenopausal at mammography. PD was positively associated with breast cancer for all methods, but with the increase in risk per standard deviation increment in PD being highest for Volpara (1.83; 95% CI: 1.51 to 2.21) and Cumulus (1.58; 1.33 to 1.88) and lower for the ImageJ-based method (1.45; 1.21 to 1.74), Quantra (1.40; 1.19 to 1.66) and SXA (1.37; 1.16 to 1.63). Women in the top PD quintile (or BI-RADS 4) had 8.26 (4.28 to 15.96), 3.94 (2.26 to 6.86), 3.38 (2.00 to 5.72), 2.99 (1.76 to 5.09), 2.55 (1.46 to 4.43) and 2.96 (0.50 to 17.5) times the risk of those in the bottom one (or BI-RADS 1), respectively, for Volpara, Quantra, Cumulus, SXA, ImageJ-based method, and BI-RADS (P for trend <0.0001 for all). The ImageJ-based method had a slightly higher ability to discriminate between cases and controls (area under the curve (AUC) for PD = 0.68, P = 0.05), and Quantra slightly lower (AUC = 0.63; P = 0.06), than Cumulus (AUC = 0.65). CONCLUSIONS: Fully-automated methods are valid alternatives to the labour-intensive "gold standard" Cumulus for quantifying density in FFDM. The choice of a particular method will depend on the aims and setting but the same approach will be required for longitudinal density assessments.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Glándulas Mamarias Humanas/anomalías , Interpretación de Imagen Radiográfica Asistida por Computador , Anciano , Densidad de la Mama , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Factores de Riesgo
17.
Development ; 138(5): 947-57, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21303848

RESUMEN

The Drosophila Dachsous and Fat proteins function as ligand and receptor, respectively, for an intercellular signaling pathway that regulates Hippo signaling and planar cell polarity. Although gene-targeted mutations in two mammalian Fat genes have been described, whether mammals have a Fat signaling pathway equivalent to that in Drosophila, and what its biological functions might be, have remained unclear. Here, we describe a gene-targeted mutation in a murine Dachsous homolog, Dchs1. Analysis of the phenotypes of Dchs1 mutant mice and comparisons with Fat4 mutant mice identify requirements for these genes in multiple organs, including the ear, kidney, skeleton, intestine, heart and lung. Dchs1 and Fat4 single mutants and Dchs1 Fat4 double mutants have similar phenotypes throughout the body. In some cases, these phenotypes suggest that Dchs1-Fat4 signaling influences planar cell polarity. In addition to the appearance of cysts in newborn kidneys, we also identify and characterize a requirement for Dchs1 and Fat4 in growth, branching and cell survival during early kidney development. Dchs1 and Fat4 are predominantly expressed in mesenchymal cells in multiple organs, and mutation of either gene increases protein staining for the other. Our analysis implies that Dchs1 and Fat4 function as a ligand-receptor pair during murine development, and identifies novel requirements for Dchs1-Fat4 signaling in multiple organs.


Asunto(s)
Cadherinas/genética , Organogénesis/genética , Transducción de Señal/genética , Animales , Cadherinas/deficiencia , Cadherinas/metabolismo , Polaridad Celular/genética , Crecimiento y Desarrollo , Riñón/crecimiento & desarrollo , Ratones , Ratones Mutantes , Transducción de Señal/fisiología
18.
Dev Growth Differ ; 55(8): 710-22, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24111778

RESUMEN

The chick Early B-cell Factor-2 and 3 (cEbf2 and cEbf3) genes are members of EBF family of helix loop helix transcription factors. The expression, regulation and importance of these genes have been extensively studied in lymphatic, nervous and muscular tissues. Recently, a new role for some members of EBF in bone development has been investigated. However, the expression profile and regulation in the axial skeleton precursor, the somite, have yet to be elucidated. Therefore, this study was aimed to investigate the expression and regulation of cEbf2 and cEbf3 genes in the developing chick embryo somite from HH4 to HH28. The spatiotemporal expression study revealed predominant localization of cEbf2 and cEbf3 in the lateral sclerotomal domains and later around vertebral cartilage anlagen of the arch and the proximal rib. Subsequently, microsurgeries, ectopic gene expression experiments were performed to analyze which tissues and factors regulate cEbf2 and cEbf3 expression. Lateral barriers experiments indicated the necessity for lateral signal(s) in the regulation of cEbf2 and cEbf3 genes. Results from tissue manipulations and ectopic gene expression experiments indicate that lateral plate-derived Bmp4 signals are necessary for the initiation and maintenance of cEbf2 and cEbf3 genes in somites. In conclusion, cEbf2 and cEbf3 genes are considered as lateral sclerotome markers which their expression is regulated by Bmp4 signals from the lateral plate mesoderm.


Asunto(s)
Proteínas Aviares/metabolismo , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/biosíntesis , Proteína Morfogenética Ósea 4/metabolismo , Pollos/fisiología , Regulación del Desarrollo de la Expresión Génica/fisiología , Transducción de Señal/fisiología , Somitos/embriología , Animales , Proteínas Aviares/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Proteína Morfogenética Ósea 4/genética , Cartílago/citología , Cartílago/embriología , Células Cultivadas , Embrión de Pollo , Somitos/citología , Columna Vertebral/citología , Columna Vertebral/embriología , Xenopus laevis
19.
Sci Total Environ ; 874: 162452, 2023 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-36870500

RESUMEN

The Okavango Panhandle is the main influent watercourse of the Okavango Delta, an inland sink of the entire sediment load of the Cubango-Okavango River Basin (CORB). The sources of pollution in the CORB, and other endorheic basins, are largely understudied when compared to exorheic systems and the world's oceans. We present the first study of the distribution of microplastic (MP) pollution in surface sediments of the Okavango Panhandle in Northern Botswana. MP concentrations (64 µm-5 mm size range) in sediment samples from the Panhandle range between 56.7 and 399.5 particles kg-1 (dry weight) when analysed with fluorescence microscopy. The concentrations of MP in the 20 µm to 5 mm grain size range (analysed with Raman spectroscopy) range between 1075.7 and 1756.3 particles kg-1. One shallow core (15 cm long) from an oxbow lake suggests that MP size decreases with depth while MP concentration increases downcore. Raman Spectroscopy revealed that the compositions of the MP are dominated by polyethene terephthalate (PET), polypropylene (PP), polyethene (PE), polystyrene (PS), and polyvinyl chloride (PVC). From this novel data set it was possible to estimate that 10.9-336.2 billion particles could be transported into the Okavango Delta annually, indicating that the region represents a significant sink for MP, raising concerns for the unique wetland ecosystem.

20.
J Cell Physiol ; 226(3): 749-61, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-20717929

RESUMEN

Glycosaminoglycans (GAGs) are critical for extracellular matrix (ECM) integrity in cartilage but mechanisms regulating their synthesis are not defined. UDP-glucose dehydrogenase (UGDH) catalyses UDP-glucose oxidation to UDP-glucuronic acid, an essential monosaccharide in many GAGs. Our previous studies in articular surface (AS) cells from embryonic joints have established pivotal roles for mitogen-activated protein kinases (MAPK) in synthesis of the unsulfated GAG, hyaluronan (HA). We investigated the functional significance of UGDH in GAG production and chondrogenesis, and determined roles for MEK-ERK and p38MAPK pathways in regulating UGDH expression and function. Inhibitors of MEK and p38MAPK reduced UGDH protein in AS cells. Treatment with TGF-ß (archetypal growth factor) increased UGDH expression, sulfated (s)-GAG/HA release and pericellular matrix formation in a p38MAPK-dependent manner. Retroviral overexpression of UGDH augmented HA/sGAG release and pericellular matrix elaboration, which were blocked by inhibiting MEK but not p38MAPK. UGDH overexpression increased cartilage nodule size in bone marrow culture, promoted chondrogenesis in limb bud micromass culture and selectively suppressed medium HA levels and modified GAG sulfation, as assessed by FACE analysis. Our data provide evidence that: (i) TGF-ß regulates UGDH expression via p38MAPK to modulate sGAG/HA secretion, (ii) MEK-ERK, but not p38MAPK facilitates UGDH-induced HA and sGAG release, and (iii) increased UGDH expression promotes chondrogenesis directly and differential modifies GAG levels and sulfation. These results indicate a more diverse role for UGDH in the support of selective GAG production than previously described. Factors regulating UGDH may provide novel candidates for restoring ECM integrity in degenerative cartilage diseases, such as osteoarthritis.Arthritis Research Campaign.


Asunto(s)
Condrogénesis , Glicosaminoglicanos/biosíntesis , Ácido Hialurónico/biosíntesis , Ácido Hialurónico/metabolismo , Uridina Difosfato Glucosa Deshidrogenasa/metabolismo , Animales , Pollos , Condrogénesis/efectos de los fármacos , Sulfatos de Condroitina/metabolismo , Electroforesis , Quinasas MAP Reguladas por Señal Extracelular/metabolismo , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Articulaciones/citología , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Quinasas de Proteína Quinasa Activadas por Mitógenos/metabolismo , Modelos Biológicos , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factor de Crecimiento Transformador beta/farmacología , Uridina Difosfato Glucosa Deshidrogenasa/genética , Proteínas Quinasas p38 Activadas por Mitógenos/antagonistas & inhibidores , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo
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