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1.
Artículo en Inglés | MEDLINE | ID: mdl-38819473

RESUMEN

PURPOSE: To report the 2-year follow-up of patients with mild-to-moderate knee osteoarthritis (OA) treated with genicular artery embolisation (GAE) as part of the GENESIS study. MATERIALS AND METHODS: Forty-six patients, median age = 60 (45-83) underwent GAE using permanent microspheres (100-300 µm). Technical success was defined as embolisation of the targeted genicular arteries. Knee Injury and Osteoarthritis Outcome Score (KOOS) and Visual Analogue Scale (VAS) (0-100 mm) were recorded at baseline, 6 weeks, 3 months, 1, 2 years. Contrast-enhanced MRI knee scans were acquired at baseline and 1 year, and evaluated with the Whole-Organ Magnetic Resonance Imaging Score (WORMS). Functional MRI brain imaging and psychometric assessments were undertaken to investigate correlation between neuropsychological phenotypes and clinical outcome. Adverse events were recorded prospectively. RESULTS: Technical success was achieved in forty patients (87%). Mean VAS improved from 58.63 (SD = 20.57, 95% CI 52.7-65.5) at baselines to 37.7 at 2-years (SD = 26.3, 95% CI 27.0-47.5). Whole and subgroup KOOS were significantly improved at each timepoint with associated reductions in analgesia usage. WORMS analysis demonstrated significant reduction in synovitis (p < 0.05) with no cases of osteonecrosis. Self-limiting skin discolouration occurred in four patients. A self-limiting groin haematoma and single case of deep-vein thrombosis due to immobilisation were also recorded. Nine patients subsequently underwent knee arthroplasty with no additional operational complexities identified. Neuropsychometric assessment elucidated a correlation between baseline catastrophising and greater reduction in pain post GAE. CONCLUSION: GAE is a safe intervention for mild-moderate knee osteoarthritis, with sustained efficacy at 2 years. These results are promising and justify ongoing controlled trials.

2.
Science ; 382(6676): 1287-1291, 2023 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-38096420

RESUMEN

The hydrogen-rich outer layers of massive stars can be removed by interactions with a binary companion. Theoretical models predict that this stripping produces a population of hot helium stars of ~2 to 8 solar masses (M☉), however, only one such system has been identified thus far. We used ultraviolet photometry to identify potential stripped helium stars then investigated 25 of them using optical spectroscopy. We identified stars with high temperatures (~60,000 to 100,000 kelvin), high surface gravities, and hydrogen-depleted surfaces; 16 stars also showed binary motion. These properties match expectations for stars with initial masses of 8 to 25 M☉ that were stripped by binary interaction. Their masses fall in the gap between subdwarf helium stars and Wolf-Rayet stars. We propose that these stars could be progenitors of stripped-envelope supernovae.

4.
Eur Arch Paediatr Dent ; 22(5): 869-877, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-33893625

RESUMEN

BACKGROUND: Drama and role play can be unlisted as methods to allow children to view problems from a range of different perspectives that may differ from their own experience. Application of drama technique to assess the cause of dental fear and anxiety in a school setting is novel. AIM: The aim of this study was to engage primary school children in the core investigation via participatory arts methodologies, namely, process drama to gain understanding of the causes of dental anxiety. DESIGN: Sixty-three children, aged 7-10 years from three primary schools participated in this study. A 90-min drama workshop was carried in each school. The children were encouraged to identify the causes of dental anxiety using key concepts from process drama. The sessions were audio-recorded and transcribed. RESULTS: Four key concepts emerged: (1) fear of the unknown; (2) unpleasant sensory experience; (3) society's perception and portrayal of the dentist; and (4) learnt negative associations with the dentist. Within each four key concepts, two sub-themes were identified. CONCLUSIONS: Role-playing and use of drama are a novel application and can reveal a considerable amount of information from the child's perspective on the cause of dental fear and anxiety.


Asunto(s)
Ansiedad al Tratamiento Odontológico , Instituciones Académicas , Niño , Ansiedad al Tratamiento Odontológico/etiología , Humanos
6.
Br J Cancer ; 113(1): 69-75, 2015 Jun 30.
Artículo en Inglés | MEDLINE | ID: mdl-26057448

RESUMEN

BACKGROUND: Malignant pleural mesothelioma (MPM) is a rare and essentially incurable malignancy most often linked with occupational exposure to asbestos fibres. In common with other malignancies, the development and progression of MPM is associated with extensive dysregulation of cell cycle checkpoint proteins that modulate cell proliferation, apoptosis, DNA repair and senescence. METHODS: The expression of cyclin-dependent kinase inhibitor p16/INK4A was evaluated by immunohistochemistry using tumour biopsy specimens from 88 MPM cases and a semi-quantitative score for p16/INK4A expression was obtained. Post-diagnosis survival and the survival benefit of chemotherapeutic intervention was correlated with p16/INK4A expression. RESULTS: A low, intermediate and high score for p16/INK4A expression was observed for 45 (51.1%), 28 (31.8%) and 15 (17.1%) of the MPM cases, respectively. Those cases with intermediate or high p16/INK4A tumour expression had a significantly better post-diagnosis survival than those cases whose tumours lost p16 expression (log-rank P<0.001). Those patients with sustained p16/INK4A expression who received chemotherapy also had a better survival than those treated patients whose tumours had lost p16/INK4A expression (log-rank P<0.001). CONCLUSIONS: Sustained p16/INK4A expression predicts better post-diagnosis survival in MPM and also better survival following chemotherapeutic intervention.


Asunto(s)
Proteínas Inhibidoras de las Quinasas Dependientes de la Ciclina/metabolismo , Mesotelioma/tratamiento farmacológico , Neoplasias Pleurales/tratamiento farmacológico , Línea Celular Tumoral , Estudios de Cohortes , Humanos , Mesotelioma/metabolismo , Mesotelioma/patología , Neoplasias Pleurales/metabolismo , Neoplasias Pleurales/patología
7.
Clin Exp Immunol ; 181(1): 39-50, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25943872

RESUMEN

Caspases are a group of proteolytic enzymes involved in the co-ordination of cellular processes, including cellular homeostasis, inflammation and apoptosis. Altered activity of caspases, particularly caspase-1, has been implicated in the development of intestinal diseases, such as inflammatory bowel disease (IBD) and colorectal cancer (CRC). However, the involvement of two related inflammatory caspase members, caspases-4 and -5, during intestinal homeostasis and disease has not yet been established. This study demonstrates that caspases-4 and -5 are involved in IBD-associated intestinal inflammation. Furthermore, we found a clear correlation between stromal caspase-4 and -5 expression levels, inflammation and disease activity in ulcerative colitis patients. Deregulated intestinal inflammation in IBD patients is associated with an increased risk of developing CRC. We found robust expression of caspases-4 and -5 within intestinal epithelial cells, exclusively within neoplastic tissue, of colorectal tumours. An examination of adjacent normal, inflamed and tumour tissue from patients with colitis-associated CRC confirmed that stromal expression of caspases-4 and -5 is increased in inflamed and dysplastic tissue, while epithelial expression is restricted to neoplastic tissue. In addition to identifying caspases-4 and -5 as potential targets for limiting intestinal inflammation, this study has identified epithelial-expressed caspases-4 and -5 as biomarkers with diagnostic and therapeutic potential in CRC.


Asunto(s)
Caspasas Iniciadoras/biosíntesis , Caspasas/biosíntesis , Colitis Ulcerosa/patología , Neoplasias Colorrectales/patología , Mucosa Intestinal/patología , Adulto , Anciano , Biomarcadores , Colitis Ulcerosa/diagnóstico , Neoplasias Colorrectales/diagnóstico , Células Epiteliales/metabolismo , Femenino , Humanos , Inflamación/patología , Mucosa Intestinal/citología , Masculino , Persona de Mediana Edad , Adulto Joven
8.
Breast Cancer Res Treat ; 149(2): 373-83, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25528022

RESUMEN

The PI3K pathway is a key mechanism of trastuzumab resistance, but early attempts to indirectly target this pathway with mTOR inhibitors have had limited success. We present the results of a preclinical study of the selective alpha/delta isoform dominant PI3K inhibitor BAY 80-6946 tested alone and in combination with HER2-targeted therapies in HER2-positive cell lines, including models with acquired resistance to trastuzumab and/or lapatinib. A panel of HER2-positive breast cancer cells were profiled for their mutational status using Sequenom MassARRAY, PTEN status by Western blot, and anti-proliferative response to BAY 80-6946 alone and in combination with the HER2-targeted therapies trastuzumab, lapatinib and afatinib. Reverse phase protein array was used to determine the effect of BAY 80-6946 on expression and phosphorylation of 68 proteins including members of the PI3K and MAPK pathways. The Boyden chamber method was used to determine if BAY 80-6946 affected cellular invasion and migration. BAY 80-6946 has anti-proliferative and anti-invasive effects when used alone in our panel of cell lines (IC50s 3.9-29.4 nM). BAY 80-6946 inhibited PI3K signalling and was effective in cells regardless of their PI3K, P53 or PTEN status. The combination of HER2-targeted therapies and BAY 80-6946 inhibited growth more effectively than either therapy used alone (with clear synergism in many cases), and can restore sensitivity to trastuzumab and lapatinib in cells with acquired resistance to either trastuzumab and/or lapatinib. The addition of BAY 80-6946 to HER2-targeted therapy could represent an improved treatment strategy for patients with refractory metastatic HER2-positive breast cancer, and should be considered for clinical trial evaluation.


Asunto(s)
Anticuerpos Monoclonales Humanizados/farmacología , Neoplasias de la Mama/genética , Resistencia a Antineoplásicos , Inhibidores de las Quinasa Fosfoinosítidos-3 , Pirimidinas/farmacología , Quinazolinas/farmacología , Receptor ErbB-2/genética , Anticuerpos Monoclonales Humanizados/administración & dosificación , Antineoplásicos/administración & dosificación , Antineoplásicos/farmacología , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Evaluación Preclínica de Medicamentos , Sinergismo Farmacológico , Femenino , Humanos , Concentración 50 Inhibidora , Lapatinib , Sistema de Señalización de MAP Quinasas/efectos de los fármacos , Mutación , Fosfohidrolasa PTEN/metabolismo , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Inhibidores de Proteínas Quinasas/administración & dosificación , Inhibidores de Proteínas Quinasas/farmacología , Pirimidinas/administración & dosificación , Quinazolinas/administración & dosificación , Receptor ErbB-2/antagonistas & inhibidores , Receptor ErbB-2/metabolismo , Transducción de Señal/efectos de los fármacos , Serina-Treonina Quinasas TOR/metabolismo , Trastuzumab
9.
Tree Physiol ; 34(5): 443-58, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24664613

RESUMEN

Gas exchange, growth, water transport and carbon (C) metabolism diminish during drought according to their respective sensitivities to declining water status. The timing of this sequence of declining physiological functions may determine how water and C relations compromise plant survival. In this paper, we test the hypothesis that the degree of asynchrony between declining C supply (photosynthesis) and C demand (growth and respiration) determines the rate and magnitude of changes in whole-plant non-structural carbohydrates (NSC) during drought. Two complementary experiments using two tree species (Eucalyptus globulus Labill. and Pinus radiata D. Don) with contrasting drought response strategies were performed to (i) assess changes in radial stem growth, transpiration, leaf water potential and gas exchange in response to chronic drought, and (ii) evaluate the concomitant impacts of these drought responses on the temporal patterns of NSC during terminal drought. The three distinct phases of water stress were delineated by thresholds of growth cessation and stomatal closure that defined the 'carbon safety margin' (i.e., the difference between leaf water potential when growth is zero and leaf water potential when net photosynthesis is zero). A wider C safety margin in E. globulus was defined by an earlier cessation of growth relative to photosynthesis that reduced the demand for NSC while maintaining C acquisition. By contrast, the narrower C safety margin in P. radiata was characterized by a synchronous decline in growth and photosynthesis, whereby growth continued under a declining supply of NSC from photosynthesis. The narrower C safety margin in P. radiata was associated with declines in starch concentrations after ∼ 90 days of chronic drought and significant depletion of starch in all organs at mortality. The observed divergence in the sensitivity of drought responses is indicative of a potential trade-off between maintaining hydraulic safety and adequate C availability.


Asunto(s)
Sequías , Eucalyptus/fisiología , Pinus/fisiología , Hojas de la Planta/metabolismo , Tallos de la Planta/crecimiento & desarrollo , Transpiración de Plantas , Metabolismo de los Hidratos de Carbono , Eucalyptus/crecimiento & desarrollo , Gases/metabolismo , Pinus/crecimiento & desarrollo , Árboles , Agua/metabolismo
10.
Colorectal Dis ; 16(1): O16-25, 2014 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24119076

RESUMEN

AIM: To date, there is no uniform consensus on whether tumour regression grade (TRG) is predictive of outcome in rectal cancer. Furthermore, the lack of standardization of TRG grading is a major source of variability in published studies. The aim of this study was to evaluate the prognostic impact of TRG in a cohort of patients with locally advanced rectal cancer treated with neoadjuvant chemoradiation therapy (CRT). In addition to the Mandard TRG, we utilized four TRG systems modified from the Mandard TRG system and applied them to the cohort to assess which TRG system is most informative. METHOD: One-hundred and fifty-three patients with a T3/T4 and/or a node-positive rectal cancer underwent neoadjuvant 5-fluorouracil-based CRT followed by surgical resection. RESULTS: Thirty-six (23.5%) patients achieving complete pathological response (ypCR) had a 5-year disease-free survival (DFS) rate of 100% compared with a DFS rate of 74% for 117 (76.5%) patients without ypCR (P = 0.003). The Royal College of Pathologists (RCPath) TRG best condenses the Mandard five-point TRG by stratifying patients into three groups with distinct 5-year DFS rates of 100%, 86% and 67%, respectively (P = 0.001). In multivariate analysis, pathological nodal status and circumferential resection margin (CRM) status, but not TRG, remained significant predictors of DFS (P = 0.002, P = 0.035 and P = 0.310, respectively). CONCLUSION: Our findings support the notion that ypCR status, nodal status after neoadjuvant CRT and CRM status, but not TRG, are predictors of long-term survival in patients with locally advanced rectal cancer.


Asunto(s)
Adenocarcinoma/patología , Quimioradioterapia , Ganglios Linfáticos/patología , Terapia Neoadyuvante , Neoplasias del Recto/patología , Adenocarcinoma/terapia , Adulto , Anciano , Anciano de 80 o más Años , Antimetabolitos Antineoplásicos/uso terapéutico , Supervivencia sin Enfermedad , Femenino , Fluorouracilo/uso terapéutico , Humanos , Escisión del Ganglio Linfático , Masculino , Persona de Mediana Edad , Análisis Multivariante , Estadificación de Neoplasias , Pronóstico , Modelos de Riesgos Proporcionales , Neoplasias del Recto/terapia , Inducción de Remisión , Resultado del Tratamiento , Carga Tumoral , Adulto Joven
11.
Tree Physiol ; 32(8): 958-67, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22874831

RESUMEN

Increased climatic variability, including extended periods of drought stress, may compromise on the health of forest ecosystems. The effects of defoliating pests on plantations may also impact on forest productivity. Interactions between climate signals and pest activity are poorly understood. In this study, we examined the combined effects of reduced water availability and defoliation on maximum photosynthetic rate (A(sat)), stomatal conductance (g(s)), plant water status and growth of Eucalyptus globulus Labill. Field-grown plants were subjected to two water-availability regimes, rain-fed (W-) and irrigated (W+). In the summer of the second year of growth, leaves from 75% of crown length removed from trees in both watering treatments and physiological responses within the canopies were examined. We hypothesized that defoliation would result in improved plant water status providing a mechanistic insight into leaf- and canopy-scale gas-exchange responses. Defoliated trees in the W+ treatment exhibited higher A(sat) and g(s) compared with non-defoliated trees, but these responses were not observed in the W- treatment. In contrast, at the whole-plant scale, maximum rates of transpiration (E(max)) and canopy conductance (G(Cmax)) and soil-to-leaf hydraulic conductance (K(P)) increased in both treatments following defoliation. As a result, plant water status was unaffected by defoliation and trees in the defoliated treatments exhibited homeostasis in this respect. Whole-plant soil-to-leaf hydraulic conductance was strongly correlated with leaf scale g(s) and A(sat) following the defoliation, providing a mechanistic insight into compensatory up-regulation of photosynthesis. Above-ground height and diameter growth were unaffected by defoliation in both water availability treatments, suggesting that plants use a range of responses to compensate for the impacts of defoliation.


Asunto(s)
Sequías , Eucalyptus/fisiología , Fotosíntesis/fisiología , Enfermedades de las Plantas , Hojas de la Planta/fisiología , Transpiración de Plantas/fisiología , Agua/fisiología , Riego Agrícola , Clima , Eucalyptus/crecimiento & desarrollo , Tallos de la Planta/crecimiento & desarrollo , Estomas de Plantas/fisiología , Lluvia , Suelo , Estrés Fisiológico , Árboles/crecimiento & desarrollo , Árboles/fisiología , Regulación hacia Arriba
12.
Br J Surg ; 99(3): 387-96, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22241325

RESUMEN

BACKGROUND: Epidemiological studies have linked obesity with many cancers. The insulin-like growth factor (IGF) 1 axis may be an important mediator in obesity-associated cancer. This study examined the relationship between IGF-1 and its receptor (IGF-1R) in oesophageal adenocarcinoma, a cancer strongly linked to obesity. METHODS: Patients with oesophageal adenocarcinoma considered suitable for attempted curative treatment were studied. Visceral adiposity was defined by waist circumference or visceral fat area. Free and total IGF-1 in serum were measured by enzyme-linked immunosorbent assay. Quantitative polymerase chain resection was used to determine mRNA expression of IGF-1 and IGF-1R in resected tumour samples. IGF-1R expression in tissue microarrays (TMAs) was quantified by immunohistochemistry. RESULTS: A total of 220 patients were studied. Total and free IGF-1 levels were significantly increased in the serum of viscerally obese patients. Gene expression analysis revealed a significant association between obesity status and both IGF-1R (P = 0·021) and IGF-1 (P = 0·031) in tumours. TMA analysis demonstrated that IGF-1R expression in resected tumours was significantly higher in viscerally obese patients than in those of normal weight (P = 0·023). Disease-specific survival was longer in patients with negative IGF-1R expression than in those with IGF-1R-positive tumours (median 60·0 versus 23·4 months; P = 0·027). CONCLUSION: This study highlighted the association of the IGF axis with visceral obesity, and a potential impact on the biology of oesophageal adenocarcinoma through its receptor. Targeting the IGF axis may have a rationale in future studies.


Asunto(s)
Adenocarcinoma/metabolismo , Neoplasias Esofágicas/metabolismo , Factor I del Crecimiento Similar a la Insulina/metabolismo , Grasa Intraabdominal/metabolismo , Adenocarcinoma/patología , Adulto , Anciano , Índice de Masa Corporal , Ensayo de Inmunoadsorción Enzimática , Neoplasias Esofágicas/patología , Femenino , Humanos , Inmunohistoquímica , Factor I del Crecimiento Similar a la Insulina/genética , Grasa Intraabdominal/patología , Masculino , Persona de Mediana Edad , Obesidad Abdominal/metabolismo , Obesidad Abdominal/patología , ARN Mensajero/metabolismo , Reacción en Cadena en Tiempo Real de la Polimerasa , Receptor IGF Tipo 1/genética , Receptor IGF Tipo 1/metabolismo , Análisis de Supervivencia , Circunferencia de la Cintura
13.
Br J Cancer ; 105(10): 1487-94, 2011 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-21989182

RESUMEN

BACKGROUND: The aim of this pilot retrospective study was to investigate the immunohistochemical expression of Cathepsin S (CatS) in three cohorts of colorectal cancer (CRC) patients (n=560). METHODS: Prevalence and association with histopathological variables were assessed across all cohorts. Association with clinical outcomes was investigated in the Northern Ireland Adjuvant Chemotherapy Trial cohort (n=211), where stage II/III CRC patients were randomised between surgery-alone or surgery with adjuvant fluorouracil/folinic acid (FU/FA) treatment. RESULTS: Greater than 95% of tumours had detectable CatS expression with significantly increased staining in tumours compared with matched normal colon (P>0.001). Increasing CatS was associated with reduced recurrence-free survival (RFS; P=0.03) among patients treated with surgery alone. Adjuvant FU/FA significantly improved RFS (hazard ratio (HR), 0.33; 95% CI, 0.12-0.89) and overall survival (OS; HR, 0.25; 95% CI, 0.08-0.81) among 36 patients with high CatS. Treatment did not benefit the 66 patients with low CatS, with a RFS HR of 1.34 (95% CI, 0.60-3.19) and OS HR of 1.33 (95% CI, 0.56-3.15). Interaction between CatS and treatment status was significant for RFS (P=0.02) and OS (P=0.04) in a multivariate model adjusted for known prognostic markers. CONCLUSION: These results signify that CatS may be an important prognostic biomarker and predictive of response to adjuvant FU/FA in CRC.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Biomarcadores de Tumor/metabolismo , Catepsinas/metabolismo , Quimioterapia Adyuvante , Neoplasias Colorrectales/tratamiento farmacológico , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Cohortes , Neoplasias Colorrectales/enzimología , Neoplasias Colorrectales/cirugía , Femenino , Fluorouracilo/administración & dosificación , Humanos , Inmunohistoquímica , Leucovorina/administración & dosificación , Masculino , Persona de Mediana Edad , Proyectos Piloto , Pronóstico
14.
Tree Physiol ; 31(7): 686-99, 2011 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-21746746

RESUMEN

The current approach to modelling pest impacts on forest net primary production (NPP) is to apply a constant modifier. This does not capture the large spatial and temporal variability in pest abundance and activity that can occur, meaning that overestimates or underestimates of pest impacts on forest NPP are likely. Taking a more mechanistic approach that incorporates an understanding of how physiology is influenced by pest attack, enables us to better capture system feedbacks and dynamics, thereby improving the capacity to predict into novel situations such as changing climate, and to account for both changes in pest activity and host responses to the growing environment now and into the future. We reviewed the effects of pests on forest NPP and found a range of responses and physiological mechanisms underlying those responses. Pest outbreaks can clearly be a major perturbation to forest NPP, and it seems likely that the frequency and intensity of pest outbreaks, and the ways in which host species respond to pest damage, will change in the future. We summarized these impacts in the form of a conceptual model at leaf, tree and stand scales, and compared the physiological processes embedded within that framework with the capacity of a representative range of NPP models to capture those processes. We found that some models can encapsulate some of the processes, but no model can comprehensively account for the range of physiological responses to pest attack experienced by trees. This is not surprising, given the paucity of empirical data for most of the world's forests, and that the models were developed primarily for other purposes. We conclude with a list of the key physiological processes and pathways that need to be included in forest growth models in order to adequately capture pest impacts on forest NPP under current and future climate scenarios, the equations that might enable this and the empirical data required to support them.


Asunto(s)
Biomasa , Cambio Climático , Modelos Biológicos , Árboles/crecimiento & desarrollo , Árboles/parasitología , Animales , Procesos Autotróficos , Respiración de la Célula , Herbivoria , Fotosíntesis , Enfermedades de las Plantas , Hojas de la Planta/metabolismo , Árboles/metabolismo
15.
J Clin Pathol ; 64(8): 649-53, 2011 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-21690244

RESUMEN

These guidelines supplement existing guidelines on HER2 testing by immunohistochemistry and in-situ hybridisation(ISH) methods in the UK. They provide a specific focus on aspects of guidance relevant to HER2 ISH testing methods, both fluorescent and chromogenic. They are formulated to give advice on methodology, interpretation and quality control for ISH-based testing of HER2 status in common tumour types, including both breast and gastric tumours. The aim is to ensure that all ISH-based testing is accurate, reliable and timely.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Hibridación in Situ/métodos , Receptor ErbB-2/metabolismo , Neoplasias Gástricas/diagnóstico , Neoplasias de la Mama/genética , Femenino , Genes erbB-2 , Humanos , Hibridación in Situ/normas , Capacitación en Servicio , Cuerpo Médico/educación , Técnicas de Sonda Molecular , Garantía de la Calidad de Atención de Salud , Control de Calidad , Proyectos de Investigación , Manejo de Especímenes , Neoplasias Gástricas/genética
17.
Plant Cell Environ ; 34(10): 1652-65, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21707651

RESUMEN

Productivity of trees can be affected by limitations in resources such as water and nutrients, and herbivory. However, there is little understanding of their interactive effects on carbon uptake and growth. We hypothesized that: (1) in the absence of defoliation, photosynthetic rate and leaf respiration would be governed by limiting resource(s) and their impact on sink limitation; (2) photosynthetic responses to defoliation would be a consequence of changing source:sink relationships and increased availability of limiting resources; and (3) photosynthesis and leaf respiration would be adjusted in response to limiting resources and defoliation so that growth could be maintained. We tested these hypotheses by examining how leaf photosynthetic processes, respiration, carbohydrate concentrations and growth rates of Eucalyptus globulus were influenced by high or low water and nitrogen (N) availability, and/or defoliation. Photosynthesis of saplings grown with low water was primarily sink limited, whereas photosynthetic responses of saplings grown with low N were suggestive of source limitation. Defoliation resulted in source limitation. Net photosynthetic responses to defoliation were linked to the degree of resource availability, with the largest responses measured in treatments where saplings were ultimately source rather than sink limited. There was good evidence of acclimation to stress, enabling higher rates of C uptake than might otherwise have occurred.


Asunto(s)
Eucalyptus/fisiología , Nitrógeno/metabolismo , Fotosíntesis/fisiología , Transpiración de Plantas/fisiología , Agua/metabolismo , Aclimatación , Transporte Biológico/fisiología , Transporte Biológico/efectos de la radiación , Dióxido de Carbono/metabolismo , Dióxido de Carbono/efectos de la radiación , Respiración de la Célula/fisiología , Deshidratación , Eucalyptus/enzimología , Eucalyptus/crecimiento & desarrollo , Eucalyptus/efectos de la radiación , Luz , Fotosíntesis/efectos de la radiación , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología , Hojas de la Planta/efectos de la radiación , Tallos de la Planta/crecimiento & desarrollo , Tallos de la Planta/fisiología , Tallos de la Planta/efectos de la radiación , Transpiración de Plantas/efectos de la radiación , Ribulosa-Bifosfato Carboxilasa/metabolismo , Plantones/metabolismo , Suelo/análisis , Estrés Fisiológico , Árboles , Regulación hacia Arriba/fisiología
18.
Br J Cancer ; 104(3): 480-7, 2011 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-21285972

RESUMEN

BACKGROUND: The CXC-chemokine expression is linked with colorectal cancer (CRC) progression but their significance in resected CRC is unclear. We explored the prognostic impact of such expression in stage II and III CRC. METHODS: Tissue microarrays were constructed from stage II and III CRC biopsies (n=254), and the expression of CXCL1 and CXCL8, and their receptors CXCR1 and CXCR2, in malignant and adjacent normal tissue was graded by immunohistochemistry and was correlated with prognostic factors. RESULTS: Expression of CXCL1, CXCR1 and CXCR2 was elevated in tumour epithelium relative to normal adjacent tissue (P<0.001). CXCL8 expression was detectable in the peritumoural inflammatory infiltrate. There was no overall association between CXCL1, CXCR1 or CXCR2 expression and prognostic endpoints; however, univariate subgroup survival analysis demonstrated an inverse association between CXCL1 and recurrence-free survival (RFS) in stage III patients (P=0.041). The CXCL8 positivity in the tumour infiltrate, however, correlated with earlier disease stage (P<0.001) and improved relapse-free survival across the cohort (P<0.001). Disease stage (P<0.001) and tumour infiltrate CXCL8 positivity (P=0.007) were associated with enhanced RFS in multivariate Cox regression analysis. CONCLUSION: Autocrine CXC-chemokine signalling may have adverse prognostic effects in early CRC. Conversely, CXCL8 positivity within the immune infiltrate may have good prognostic significance.


Asunto(s)
Quimiocinas CXC/biosíntesis , Neoplasias Colorrectales/metabolismo , Mucosa Intestinal/metabolismo , Células del Estroma/metabolismo , Neoplasias Colorrectales/patología , Humanos , Interleucina-8/biosíntesis , Estadificación de Neoplasias , Pronóstico
19.
Tree Physiol ; 30(8): 957-68, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20601436

RESUMEN

We examined spatial and temporal dynamics of foliage respiration in canopies of dominant and suppressed Eucalyptus globulus trees to better understand processes regulating foliage respiration in a young fast-growing stand. Temperature response functions and seasonal measures of respiration (measured at a reference temperature of 15 °C, R15) were studied for approximately 1 year to (i) examine controls on respiration as a function of canopy position, foliar nitrogen and non-structural carbohydrate concentrations and (ii) assess the capacity for thermal acclimation within E. globulus canopies. The short-term temperature response of respiration varied both with canopy position and seasonally. Area-based R(15) measurements declined with increasing canopy depth and were strongly related to foliar N concentrations, especially in upper-canopy positions. R15 was negatively correlated with the average temperature of the preceding 14 days, a pattern consistent with thermal acclimation. In suppressed canopies, R15 was higher than that at similar canopy heights in dominant trees. Similarly, foliar concentrations of non-structural carbohydrates were also relatively higher in suppressed canopies than dominant canopies, providing support for a substrate-based model of leaf respiration. Our data highlight the dynamic nature of foliar respiration within E. globulus canopies, which contrasts with the generally simplistic representation of respiration within most process-based models.


Asunto(s)
Ecosistema , Eucalyptus/fisiología , Hojas de la Planta/fisiología , Transpiración de Plantas/fisiología , Estaciones del Año , Aclimatación
20.
Br J Dermatol ; 163(2): 345-52, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20346029

RESUMEN

BACKGROUND: Changes in genomic DNA methylation associated with cancer include global DNA hypomethylation and gene-specific hyper- or hypomethylation. We have previously identified a genetic variant in the MTHFR gene involved in the methylation pathway which confers risk for the development of squamous cell carcinoma (SCC) in renal transplant patients. This genetic variant has also been discovered to confer SCC risk in nontransplant patients with low folate status. OBJECTIVES: To explore the methylation profile of SCC compared with adjacent non-neoplastic skin using pyrosequencing, and to elucidate whether the MTHFR polymorphism impacts upon the methylation patterns in SCC. METHODS: We used pyrosequencing to evaluate global (using long interspersed nuclear element 1) and gene-specific (p16 and MGMT) methylation status in 47 SCCs and 40 adjacent autologous non-neoplastic skin samples in those with (n = 16) and without (n = 17) the MTHFR polymorphism. RESULTS: Pyrosequencing methylation analysis revealed that SCC was hypomethylated compared with adjacent non-neoplastic skin (P < 0.04). Patients with the MTHFR polymorphism had higher levels of global methylation in tumours and non-neoplastic skin compared with those without the MTHFR polymorphism (P < 0.002). There was no association between levels of methylation in tumour and non-neoplastic skin for the genes MGMT and p16. CONCLUSIONS: Global hypomethylation appears to be a feature of SCC. Aberrant methylation of DNA appears related to polymorphisms of MTHFR. Such findings suggest that intervention in the form of demethylating agents or folate supplementation might be beneficial in the treatment or prevention of SCC.


Asunto(s)
Carcinoma de Células Escamosas/genética , Metilación de ADN/genética , Trasplante de Riñón , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Proteínas de Neoplasias/genética , Polimorfismo Genético , Neoplasias Cutáneas/genética , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Secuencia de ADN/métodos
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