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1.
Genes Dev ; 35(7-8): 528-541, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33737385

RESUMEN

Esophageal squamous cell carcinoma (ESCC) is one of the most lethal cancers worldwide and evolves often to lung metastasis. P53R175H (homologous to Trp53R172H in mice) is a common hot spot mutation. How metastasis is regulated by p53R175H in ESCC remains to be investigated. To investigate p53R175H-mediated molecular mechanisms, we used a carcinogen-induced approach in Trp53R172H/- mice to model ESCC. In the primary Trp53R172H/- tumor cell lines, we depleted Trp53R172H (shTrp53) and observed a marked reduction in cell invasion in vitro and lung metastasis burden in a tail-vein injection model in comparing isogenic cells (shCtrl). Furthermore, we performed bulk RNA-seq to compare gene expression profiles of metastatic and primary shCtrl and shTrp53 cells. We identified the YAP-BIRC5 axis as a potential mediator of Trp53R172H -mediated metastasis. We demonstrate that expression of Survivin, an antiapoptotic protein encoded by BIRC5, increases in the presence of Trp53R172H Furthermore, depletion of Survivin specifically decreases Trp53R172H-driven lung metastasis. Mechanistically, Trp53R172H but not wild-type Trp53, binds with YAP in ESCC cells, suggesting their cooperation to induce Survivin expression. Furthermore, Survivin high expression level is associated with increased metastasis in several GI cancers. Taken together, this study unravels new insights into how mutant p53 mediates metastasis.


Asunto(s)
Neoplasias Pulmonares/fisiopatología , Survivin/genética , Survivin/metabolismo , Animales , Línea Celular Tumoral , Modelos Animales de Enfermedad , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias Pulmonares/genética , Ratones , Mutación , Metástasis de la Neoplasia , Transcriptoma , Proteína p53 Supresora de Tumor/metabolismo
2.
PLoS Genet ; 13(8): e1006938, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28787442

RESUMEN

Advances in genomics in recent years have provided key insights into defining cancer subtypes "within-a-tissue"-that is, respecting traditional anatomically driven divisions of medicine. However, there remains a dearth of data regarding molecular profiles that are shared across tissues, an understanding of which could lead to the development of highly versatile, broadly applicable therapies. Using data acquired from The Cancer Genome Atlas (TCGA), we performed a transcriptomics-centered analysis on 1494 patient samples, comparing the two major histological subtypes of solid tumors (adenocarcinomas and squamous cell carcinomas) across organs, with a focus on tissues in which both subtypes arise: esophagus, lung, and uterine cervix. Via principal component and hierarchical clustering analysis, we discovered that histology-driven differences accounted for a greater degree of inherent molecular variation in the tumors than did tissue of origin. We then analyzed differential gene expression, DNA methylation, and non-coding RNA expression between adenocarcinomas and squamous cell carcinomas and found 1733 genes, 346 CpG sites, and 42 microRNAs in common between organ sites, indicating specific adenocarcinoma-associated and squamous cell carcinoma-associated molecular patterns that were conserved across tissues. We then identified specific pathways that may be critical to the development of adenocarcinomas and squamous cell carcinomas, including Liver X receptor activation, which was upregulated in adenocarcinomas but downregulated in squamous cell carcinomas, possibly indicating important differences in cancer cell metabolism between these two histological subtypes of cancer. In addition, we highlighted genes that may be common drivers of adenocarcinomas specifically, such as IGF2BP1, which suggests a possible link between embryonic development and tumor subtype. Altogether, we demonstrate the need to consider biological similarities that transcend anatomical boundaries to inform the development of novel therapeutic strategies. All data sets from our analysis are available as a resource for further investigation.


Asunto(s)
Adenocarcinoma/genética , Carcinoma de Células Escamosas/genética , Regulación Neoplásica de la Expresión Génica , Transcriptoma , Adenocarcinoma/diagnóstico , Carcinoma de Células Escamosas/diagnóstico , Cuello del Útero/patología , Metilación de ADN , Regulación hacia Abajo , Epigenómica , Esófago/patología , Femenino , Marcadores Genéticos , Variación Genética , Humanos , Receptores X del Hígado/genética , Receptores X del Hígado/metabolismo , Pulmón/patología , MicroARNs/genética , MicroARNs/metabolismo , Análisis de Componente Principal , Pronóstico , Proteínas de Unión al ARN/genética , Proteínas de Unión al ARN/metabolismo , Reproducibilidad de los Resultados , Regulación hacia Arriba
3.
Phys Chem Chem Phys ; 21(14): 7567-7575, 2019 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-30899929

RESUMEN

A facile strategy of color switching has been developed through reversibly multicolored photoluminescence modulation in dual rare-earth element modified 0.94Bi0.5Na0.5TiO3-0.06BaTiO3 (BNT6BT-Tb/Eu-x) relaxor ferroelectrics via the application of in situ electric fields. By virtue of the chemical and charge disorder induced by the trivalent rare earth ions, more dynamic and weakly correlated polar nanoregions are formed, which facilitate a reversible transition between the randomly oriented polar nanoregions and unstable ordered ferroelectric domains under an electric field. The electroceramics thus become more ergodic, exhibiting giant and reversible electric field-induced strain as well as structural symmetry changes around the luminescent centers and the BNT6BT-Tb/Eu-0.04 sample reveals the highest ergodicity degree. Accordingly, the overall emission color can be modulated reversibly between orange and green by purely physical stimuli (an electric field). The design of the color modulation elucidated in this work should inspire similar research expanded to other soft ferroelectrics for optical tuning and displays at ambient temperature. This should also be helpful for the realization of regulating the physical coupling (photoluminescence color switching-ergodic relaxor ferroelectrics) in multifunctional inorganic materials.

4.
BJOG ; 125(4): 451-459, 2018 03.
Artículo en Inglés | MEDLINE | ID: mdl-29125674

RESUMEN

OBJECTIVE: To examine preferences for follow-up testing in women screened with high or intermediate risk for Down syndrome in the first or second trimester. DESIGN: Prospective cohort study. SETTING: Three public hospitals in Hong Kong, China. SAMPLE: Women with pregnancies termed as high risk (≥1:250; HR) or intermediate risk (1:251-1200; IR) for Down syndrome. METHODS: Women with pregnancies screened as HR were offered the choices of: (1) an invasive test plus chromosomal microarray (CMA) to obtain more detailed fetal genetic information; (2) non-invasive cell-free prenatal DNA screening (NIPT) to detect trisomies 13, 18 and 21, and to avoid procedure-related miscarriage; and (3) to decline any further testing. Women received standardised counselling informing them that the reporting times were identical, the procedure miscarriage risk was 0.1-0.2% and that there was no charge for screening. Women with IR pregnancies (1:251-1200) were offered NIPT as a secondary screening test. MAIN OUTCOME MEASURES: Uptake rate for NIPT. RESULTS: Three hundred and forty-seven women had pregnancies deemed as HR; 344 (99.1%) women opted for follow-up testing, 216 (62.2%) of whom chose NIPT. Five hundred and seven of 614 women (82.6%) with IR risk chose NIPT. Seven (21%) of 34 women with nuchal translucency ≥3.5 mm opted for NIPT. CONCLUSION: In a setting where reporting times are similar and there is no cost difference between options, approximately 60% of women with pregnancies classed as HR would opt for NIPT, offering simple but limited aneuploidy assessment, over a diagnostic procedure with comprehensive and more detailed assessment. TWEETABLE ABSTRACT: 60% of pregnant Chinese women prefer NIPT over CMA when screened as high risk for Down syndrome.


Asunto(s)
Aborto Espontáneo/prevención & control , Ácidos Nucleicos Libres de Células/análisis , Análisis Citogenético , Síndrome de Down/diagnóstico , Pruebas Genéticas , Prioridad del Paciente/estadística & datos numéricos , Aborto Espontáneo/etiología , Adulto , Estudios de Cohortes , Análisis Citogenético/métodos , Análisis Citogenético/estadística & datos numéricos , Femenino , Pruebas Genéticas/métodos , Pruebas Genéticas/estadística & datos numéricos , Hong Kong , Humanos , Análisis por Micromatrices , Embarazo , Diagnóstico Prenatal/efectos adversos , Diagnóstico Prenatal/métodos , Diagnóstico Prenatal/psicología , Diagnóstico Prenatal/estadística & datos numéricos , Ajuste de Riesgo/métodos
6.
Build Environ ; 135: 297-307, 2018 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-32287983

RESUMEN

Twisted wind flows generated by the complex terrain of Hong Kong induce two types of complication to Air Ventilation Assessment (AVA), first, imposing a false boundary condition on the wind tunnel tests done for AVA and, second, creating an ambiguity in determining the approaching wind direction in calculating the probability of occurrence of winds. The latter issue is partially solved using correction methods in post-analysis of AVA but the accuracy of these methods is not yet accessed. This study employs two twisted wind profiles to test an urban area in a boundary layer wind tunnel to investigate the influence of twisted wind flows on the outcomes of AVA and to estimate the accuracy of three common correction methods: No-Shift, Threshold, and Proportional methods. The results reveal significant differences in wind speeds at the pedestrian level for twisted and conventional wind flows at locations with low building densities. The discrepancies in wind speeds are minimum at the locations where the density of buildings is high. The indicators calculated by the No-Shift method frequently deviate from those of the twisted wind flows, while the Threshold and Proportional methods routinely over-predict the indicators of AVA.

7.
Am J Hematol ; 92(8): E138-E145, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-28474779

RESUMEN

The tumor suppressors B-lymphocyte-induced maturation protein-1 (BLIMP-1) and p53 play a crucial role in B-cell lymphomas, and their inactivation contributes to the pathogenesis of a wide spectrum of lymphoid malignancies, including diffuse large B-cell lymphomas (DLBCLs). Patients with activated B-cell-like (ABC) DLBCL may present with loss of BLIMP-1, c-Myc over-expression, decreased p53, and poor prognosis. Nevertheless, there is a lack of in vivo models recapitulating the biology of high-grade ABC DLBCL. We therefore aimed to develop an in vivo model aiming to recapitulate the phenotype observed in this cohort of patients. A Cre-Lox approach was used to achieve inactivation of both p53 and BLIMP-1 in murine B-cells. Contextual ablation of BLIMP-1 and p53 led to development of IgM-positive B-cell lymphoma with an aggressive phenotype, supported by c-Myc up-regulation, and accumulation of somatic mutations, as demonstrated by whole exome sequencing. Sensitivity of B-tumor cells to BTK inhibition was demonstrated. This model mirrors what reported in patients with ABC DLBLC, and therefore represents a novel model for studying the biology of ABC-DLBCL harboring the dual loss of BLIMP-1/p53 and c-Myc over-expression.


Asunto(s)
Linfocitos B/metabolismo , Linfocitos B/patología , Transformación Celular Neoplásica/genética , Proteínas Represoras/deficiencia , Proteína p53 Supresora de Tumor/deficiencia , Animales , Linfocitos B/efectos de los fármacos , Biomarcadores , Evolución Clonal/genética , Modelos Animales de Enfermedad , Expresión Génica , Regulación Neoplásica de la Expresión Génica , Genes myc , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Ratones , Ratones Transgénicos , Factor 1 de Unión al Dominio 1 de Regulación Positiva , Inhibidores de Proteínas Quinasas/farmacología
8.
Aust N Z J Psychiatry ; 51(1): 23-31, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27313138

RESUMEN

INTRODUCTION: There is mixed evidence in the literature on the role of inflammation in major depressive disorder. Contradictory findings are attributed to lack of rigorous characterization of study subjects, to the presence of concomitant medical illnesses, to the small sample sizes, and to the limited number of cytokines tested. METHODS: Subjects aged 18-70 years, diagnosed with major depressive disorder and presenting with chronic course of illness, as well as matched controls ( n = 236), were evaluated by trained raters and provided blood for cytokine measurements. Cytokine levels in EDTA plasma were measured with the MILLIPLEX Multi-Analyte Profiling Human Cytokine/Chemokine Assay employing Luminex technology. The Wilcoxon rank-sum test was used to compare cytokine levels between major depressive disorder subjects and healthy volunteers, before (interleukin [IL]-1ß, IL-6, and tumor necrosis factor-α) and after Bonferroni correction for multiple comparisons (IL-1α, IL-2, IL-3, IL-4, IL-5, IL-7, IL-8, IL-10, IL-12(p40), IL-12(p70), IL-13, IL-15, IFN-γ-inducible protein 10, Eotaxin, interferon-γ, monotype chemoattractant protein-1, macrophage inflammatory protein-1α, granulocyte-macrophage colony-stimulating factor and vascular endothelial growth factor). RESULTS: There were no significant differences in cytokine levels between major depressive disorder subjects and controls, both prior to and after correction for multiple analyses (significance set at p ⩽ 0.05 and p ⩽ 0.002, respectively). CONCLUSION: Our well-characterized examination of cytokine plasma levels did not support the association of major depressive disorder with systemic inflammation. The heterogeneity of major depressive disorder, as well as a potential sampling bias selecting for non-inflammatory depression, might have determined our findings discordant with the literature.


Asunto(s)
Citocinas/sangre , Trastorno Depresivo Mayor/sangre , Inflamación/sangre , Adolescente , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto Joven
11.
Build Environ ; 124: 245-257, 2017 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32287974

RESUMEN

Owing to the void space at lower heights, lift-up buildings have high building permeability at ground level and subsequently improve the air circulation in congested urban areas. Despite this advantage, the lift-up design has been sparsely adopted for buildings in urban areas partly because of the lack of understanding of the combined effects of building dimensions and lift-up design on the surrounding pedestrian level wind (PLW) field. Therefore, this study aims to investigate the influence of lift-up buildings with different aspect ratios (height/width) on the surrounding PLW field and pedestrian wind comfort level. Five lift-up buildings with aspect ratios 4:1 to 0.5:1 were tested in a boundary layer wind tunnel and results were compared with those of five buildings with similar dimensions but without lift-up design. The results reveal a strong dependence of the maximum wind speed in lift-up areas with building height, which results subsequently a small area of acceptable wind conditions near tall and slender lift-up buildings. Lift-up designs adopted for short and wide buildings produce larger areas of pedestrian wind comfort. The central cores modified with corner modifications are effective in increasing the pedestrian wind comfort in the lift-up area of tall and slender buildings.

12.
Build Environ ; 117: 154-165, 2017 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-32362712

RESUMEN

Modern megacities are teeming with closely-spaced tall buildings, which limit air circulation at the pedestrian level. The resultant lack of air circulation creates poorly ventilated areas with accumulated air pollutants and thermal discomfort in the summer. To improve air circulation at the pedestrian level, buildings may be designed to have a 'lift-up' shape, in which the main structure is supported by a central core, columns or shear walls. However, a lack of knowledge on the influence of the 'lift-up' design on the surrounding wind environment limits the use of 'lift-up' buildings. This study aims to investigate the influence of 'lift-up' buildings and their dimensions on the pedestrian-level wind environments using wind tunnel tests. A parametric study was undertaken by using 9 'lift-up' building models with different core heights and widths. The results were compared with the surrounding wind environment of a control building with similar dimensions. The results reveal that the 'lift-up' core height is the most influential parameter and governs the area and magnitude of high and low wind speed zones around such buildings. Based on wind tunnel test results and a selected comfort criterion, appropriate core dimensions could be selected to have acceptable wind conditions near lift-up buildings.

13.
Ann Rheum Dis ; 75(6): 1133-8, 2016 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26318385

RESUMEN

OBJECTIVES: To evaluate the risk of opportunistic infections (OIs) in patients with rheumatoid arthritis (RA) treated with tofacitinib. METHODS: Phase II, III and long-term extension clinical trial data (April 2013 data-cut) from the tofacitinib RA programme were reviewed. OIs defined a priori included mycobacterial and fungal infections, multidermatomal herpes zoster and other viral infections associated with immunosuppression. For OIs, we calculated crude incidence rates (IRs; per 100 patient-years (95% CI)); for tuberculosis (TB) specifically, we calculated rates stratified by patient enrolment region according to background TB IR (per 100 patient-years): low (≤0.01), medium (>0.01 to ≤0.05) and high (>0.05). RESULTS: We identified 60 OIs among 5671 subjects; all occurred among tofacitinib-treated patients. TB (crude IR 0.21, 95% CI of (0.14 to 0.30)) was the most common OI (n=26); median time between drug start and diagnosis was 64 weeks (range 15-161 weeks). Twenty-one cases (81%) occurred in countries with high background TB IR, and the rate varied with regional background TB IR: low 0.02 (0.003 to 0.15), medium 0.08 (0.03 to 0.21) and high 0.75 (0.49 to 1.15). In Phase III studies, 263 patients diagnosed with latent TB infection were treated with isoniazid and tofacitinib concurrently; none developed TB. For OIs other than TB, 34 events were reported (crude IR 0.25 (95% CI 0.18 to 0.36)). CONCLUSIONS: Within the global tofacitinib RA development programme, TB was the most common OI reported but was rare in regions of low and medium TB incidence. Patients who screen positive for latent TB can be treated with isoniazid during tofacitinib therapy.


Asunto(s)
Antirreumáticos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Infecciones Oportunistas/inducido químicamente , Piperidinas/efectos adversos , Pirimidinas/efectos adversos , Pirroles/efectos adversos , Tuberculosis/inducido químicamente , Antirreumáticos/uso terapéutico , Artritis Reumatoide/epidemiología , Artritis Reumatoide/inmunología , Ensayos Clínicos como Asunto , Humanos , Huésped Inmunocomprometido , Inmunosupresores/efectos adversos , Inmunosupresores/uso terapéutico , Incidencia , Janus Quinasa 3/antagonistas & inhibidores , Infecciones Oportunistas/epidemiología , Infecciones Oportunistas/inmunología , Piperidinas/uso terapéutico , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/uso terapéutico , Pirimidinas/uso terapéutico , Pirroles/uso terapéutico , Medición de Riesgo , Tuberculosis/epidemiología , Tuberculosis/inmunología
16.
Horm Metab Res ; 47(11): 833-8, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26267327

RESUMEN

Identification of germline mutation in patients with apparently sporadic pheochromocytomas and paragangliomas is crucial. Clinical indicators, which include young age, bilateral or multifocal, extra-adrenal, malignant, or recurrent tumors, predict the likelihood of harboring germline mutation in Caucasian subjects. However, data on the prevalence of germline mutation, as well as the applicability of these clinical indicators in Chinese, are lacking. We conducted a cross-sectional study at a single endocrine tertiary referral center in Hong Kong. Subjects with pheochromocytomas and paragangliomas were evaluated for the presence of germline mutations involving 10 susceptibility genes, which included NF1, RET, VHL, SDHA, SDHB, SDHC, SDHD, TMEM 127, MAX, and FH genes. Clinical indicators were assessed for their association with the presence of germline mutations. Germline mutations, 2 being novel, were found in 24.4% of the 41 Chinese subjects recruited and 11.4% among those with apparently sporadic presentation. The increasing number of the afore-mentioned clinical indicators significantly correlated with the likelihood of harboring germline mutation in one of the 10 susceptibility genes. (r=0.757, p=0.026). The presence of 2 or more clinical indicators should prompt genetic testing for germline mutations in Chinese subjects. In conclusion, our study confirmed that a significant proportion of Chinese subjects with apparently sporadic pheochromocytoma and paraganglioma harbored germline mutations and these clinical indicators identified from Caucasians series were also applicable in Chinese subjects. This information will be of clinical relevance in the design of appropriate genetic screening strategies in Chinese populations.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales/genética , Pueblo Asiatico/genética , Predisposición Genética a la Enfermedad , Paraganglioma/genética , Feocromocitoma/genética , Adulto , China , Mutación de Línea Germinal/genética , Humanos , Persona de Mediana Edad , Curva ROC
17.
BMC Med Inform Decis Mak ; 15: 43, 2015 Jun 02.
Artículo en Inglés | MEDLINE | ID: mdl-26032596

RESUMEN

BACKGROUND: Similarity-based retrieval of Electronic Health Records (EHRs) from large clinical information systems provides physicians the evidence support in making diagnoses or referring examinations for the suspected cases. Clinical Terms in EHRs represent high-level conceptual information and the similarity measure established based on these terms reflects the chance of inter-patient disease co-occurrence. The assumption that clinical terms are equally relevant to a disease is unrealistic, reducing the prediction accuracy. Here we propose a term weighting approach supported by PubMed search engine to address this issue. METHODS: We collected and studied 112 abdominal computed tomography imaging examination reports from four hospitals in Hong Kong. Clinical terms, which are the image findings related to hepatocellular carcinoma (HCC), were extracted from the reports. Through two systematic PubMed search methods, the generic and specific term weightings were established by estimating the conditional probabilities of clinical terms given HCC. Each report was characterized by an ontological feature vector and there were totally 6216 vector pairs. We optimized the modified direction cosine (mDC) with respect to a regularization constant embedded into the feature vector. Equal, generic and specific term weighting approaches were applied to measure the similarity of each pair and their performances for predicting inter-patient co-occurrence of HCC diagnoses were compared by using Receiver Operating Characteristics (ROC) analysis. RESULTS: The Areas under the curves (AUROCs) of similarity scores based on equal, generic and specific term weighting approaches were 0.735, 0.728 and 0.743 respectively (p < 0.01). In comparison with equal term weighting, the performance was significantly improved by specific term weighting (p < 0.01) but not by generic term weighting. The clinical terms "Dysplastic nodule", "nodule of liver" and "equal density (isodense) lesion" were found the top three image findings associated with HCC in PubMed. CONCLUSIONS: Our findings suggest that the optimized similarity measure with specific term weighting to EHRs can improve significantly the accuracy for predicting the inter-patient co-occurrence of diagnosis when compared with equal and generic term weighting approaches.


Asunto(s)
Diagnóstico , Registros Electrónicos de Salud , Aplicaciones de la Informática Médica , PubMed , Terminología como Asunto , Hong Kong , Humanos
20.
Hong Kong Med J ; 21(6): 569-72, 2015 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-26634375

RESUMEN

Mycoplasma pneumoniae infection usually presents with upper and lower respiratory tract infection. Extrapulmonary involvement is not uncommon, however. We report two cases of predominantly extrapulmonary manifestations of Mycoplasma pneumoniae infection without significant pulmonary involvement. Both cases were diagnosed by serology. These cases illustrate the diversity of clinical presentations of Mycoplasma pneumoniae infection. Clinicians should maintain a high index of suspicion.


Asunto(s)
Edema Encefálico/microbiología , Eritema Multiforme/microbiología , Neumonía por Mycoplasma/complicaciones , Resultado Fatal , Humanos , Masculino , Persona de Mediana Edad , Mycoplasma pneumoniae , Neumonía por Mycoplasma/sangre , Neumonía por Mycoplasma/microbiología , Pruebas Serológicas , Adulto Joven
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