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1.
Public Health ; 218: 12-20, 2023 May.
Artículo en Inglés | MEDLINE | ID: mdl-36933354

RESUMEN

INTRODUCTION: The UK shielding policy intended to protect people at the highest risk of harm from COVID-19 infection. We aimed to describe intervention effects in Wales at 1 year. METHODS: Retrospective comparison of linked demographic and clinical data for cohorts comprising people identified for shielding from 23 March to 21 May 2020; and the rest of the population. Health records were extracted with event dates between 23 March 2020 and 22 March 2021 for the comparator cohort and from the date of inclusion until 1 year later for the shielded cohort. RESULTS: The shielded cohort included 117,415 people, with 3,086,385 in the comparator cohort. The largest clinical categories in the shielded cohort were severe respiratory condition (35.5%), immunosuppressive therapy (25.9%) and cancer (18.6%). People in the shielded cohort were more likely to be female, aged ≥50 years, living in relatively deprived areas, care home residents and frail. The proportion of people tested for COVID-19 was higher in the shielded cohort (odds ratio [OR] 1.616; 95% confidence interval [CI] 1.597-1.637), with lower positivity rate incident rate ratios 0.716 (95% CI 0.697-0.736). The known infection rate was higher in the shielded cohort (5.9% vs 5.7%). People in the shielded cohort were more likely to die (OR 3.683; 95% CI: 3.583-3.786), have a critical care admission (OR 3.339; 95% CI: 3.111-3.583), hospital emergency admission (OR 2.883; 95% CI: 2.837-2.930), emergency department attendance (OR 1.893; 95% CI: 1.867-1.919) and common mental disorder (OR 1.762; 95% CI: 1.735-1.789). CONCLUSION: Deaths and healthcare utilisation were higher amongst shielded people than the general population, as would be expected in the sicker population. Differences in testing rates, deprivation and pre-existing health are potential confounders; however, lack of clear impact on infection rates raises questions about the success of shielding and indicates that further research is required to fully evaluate this national policy intervention.


Asunto(s)
COVID-19 , Humanos , Femenino , Masculino , COVID-19/epidemiología , COVID-19/prevención & control , Estudios Retrospectivos , Gales/epidemiología , Pandemias/prevención & control , Salud Pública , Web Semántica , Política Pública
2.
Solid State Nucl Magn Reson ; 120: 101811, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35792451

RESUMEN

We study the metal-organic framework (MOF) ZIF-67 with 1H and 13C nuclear magnetic resonance (NMR). In addition to the usual orbital chemical shifts, we observe spinning sideband manifolds in the NMR spectrum due to hyperfine interactions of the paramagnetic cobalt with 1H and 13C. Both orbital and paramagnetic chemical shifts are in good agreement with values calculated from first principles, allowing high-confidence assignment of the observed peaks to specific sites within the MOF. Our measured resonance shifts, line shapes, and spin lattice relaxation rates are also consistent with calculated values. We show that molecules in the pores of the MOF can exhibit high-resolution NMR spectra with fast spin lattice relaxation rates due to dipole-dipole couplings to the Co2+ nodes in the ZIF-67 lattice, showcasing NMR spectroscopy as a powerful tool for identification and characterization of "guests" that may be hosted by the MOF in electrochemical and catalytic applications.

3.
Proc Natl Acad Sci U S A ; 116(52): 26633-26643, 2019 Dec 26.
Artículo en Inglés | MEDLINE | ID: mdl-31843909

RESUMEN

Corneal epithelia have limited self-renewal and therefore reparative capacity. They are continuously replaced by transient amplifying cells which spawn from stem cells and migrate from the periphery. Because this view has recently been challenged, our goal was to resolve the conflict by giving mice annular injuries in different locations within the corneolimbal epithelium, then spatiotemporally fate-mapping cell behavior during healing. Under these conditions, elevated proliferation was observed in the periphery but not the center, and wounds predominantly resolved by centripetally migrating limbal epithelia. After wound closure, the central corneal epithelium was completely replaced by K14+ limbal-derived clones, an observation supported by high-resolution fluorescence imaging of genetically marked cells in organ-cultured corneas and via computational modeling. These results solidify the essential role of K14+ limbal epithelial stem cells for wound healing and refute the notion that stem cells exist within the central cornea and that their progeny have the capacity to migrate centrifugally.

4.
Behav Med ; 48(4): 320-330, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34086534

RESUMEN

Nationally, opioid overdose remains strikingly persistent among people experiencing homelessness and housing instability. Limited information is available about the characteristics of this phenomenon in economically disadvantaged communities of color. This study sought to evaluate the association between key contextual factors and experiencing a non-fatal opioid overdose among people who use heroin in Washington Heights, New York City. We conducted a cross-sectional survey (N = 101) among participants seeking harm reduction services who reported heroin use in the last three months. Binary logistic regression models examined the association between key social and structural factors and the likelihood of ever experiencing a non-fatal opioid overdose and recently experiencing a non-fatal opioid overdose. The majority of the sample reported housing instability and lived in poverty; almost 42% were homeless. After adjustment, participants who injected heroin were more likely to have ever experienced a non-fatal opioid overdose. Also, younger participants who reported hunger in the last six months were more likely to have experienced a non-fatal opioid overdose in the last three months. Findings suggest the role of structural vulnerability in shaping overdose risk among the participants. Overdose prevention strategies should consider factors of the social and economic environment to mitigate barriers to accessing health and social services within the context of the current opioid crisis.


Asunto(s)
Sobredosis de Droga , Sobredosis de Opiáceos , Estudios Transversales , Sobredosis de Droga/epidemiología , Heroína , Inestabilidad de Vivienda , Humanos , Ciudad de Nueva York/epidemiología , Washingtón
5.
Br J Cancer ; 124(12): 1921-1933, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-33785878

RESUMEN

BACKGROUND: Dynamic transitions of tumour cells along the epithelial-mesenchymal axis are important in tumorigenesis, metastasis and therapy resistance. METHODS: In this study, we have used cell lines, 3D spheroids and tumour samples in a variety of cell biological and transcriptome analyses to highlight the cellular and molecular dynamics of OSCC response to ionising radiation. RESULTS: Our study demonstrates a prominent hybrid epithelial-mesenchymal state in oral squamous cell carcinoma cells and tumour samples. We have further identified a key role for levels of E-cadherin in stratifying the hybrid cells to compartments with varying levels of radiation response and radiation-induced epithelial-mesenchymal transition. The response to radiation further entailed the generation of a new cell population with low expression levels of E-cadherin, and positive for Vimentin (ECADLow/Neg-VIMPos), a phenotypic signature that showed an enhanced capacity for radiation resistance and invasion. At the molecular level, transcriptome analysis of spheroids in response to radiation showed an initial burst of misregulation within the first 30 min that further declined, although still highlighting key alterations in gene signatures. Among others, pathway analysis showed an over-representation for the Wnt signalling pathway that was further confirmed to be functionally involved in the generation of ECADLow/Neg-VIMPos population, acting upstream of radiation resistance and tumour cell invasion. CONCLUSION: This study highlights the functional significance and complexity of tumour cell remodelling in response to ionising radiation with links to resistance and invasive capacity. An area of less focus in conventional radiotherapy, with the potential to improve treatment outcomes and relapse-free survival.


Asunto(s)
Carcinoma de Células Escamosas/patología , Transición Epitelial-Mesenquimal , Neoplasias de la Boca/patología , Tolerancia a Radiación/genética , Carcinoma de Células Escamosas/genética , Línea Celular Tumoral , Movimiento Celular/genética , Transición Epitelial-Mesenquimal/genética , Transición Epitelial-Mesenquimal/efectos de la radiación , Perfilación de la Expresión Génica , Regulación Neoplásica de la Expresión Génica/efectos de la radiación , Genes de Cambio/fisiología , Genes de Cambio/efectos de la radiación , Estudios de Asociación Genética , Humanos , Neoplasias de la Boca/genética , Invasividad Neoplásica , Fenotipo , Radiación Ionizante , Transcriptoma/efectos de la radiación , Vía de Señalización Wnt/genética , Vía de Señalización Wnt/efectos de la radiación
6.
Anaesthesia ; 76(11): 1475-1481, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33780550

RESUMEN

The Emergency Medical Retrieval and Transfer Service for Wales launched in 2015. This service delivers senior pre-hospital doctors and advanced critical care practitioners to the scene of time-critical life- and limb-threatening incidents to provide advanced decision-making and pre-hospital clinical care. The impact of the service on 30-day mortality was evaluated retrospectively using a data linkage system. The study included patients who sustained moderate-to-severe blunt traumatic injuries (injury severity score ≥ 9) between 27 April 2015 and 30 November 2018. The association between pre-hospital management by the Emergency Medical Retrieval and Transfer Service and 30-day mortality was assessed using multivariable logistic regression. In total, data from 4035 patients were analysed, of which 412 (10%) were treated by the Emergency Medical Retrieval and Transfer Service. A greater proportion of patients treated by the Emergency Medical Retrieval and Transfer Service had an injury severity score ≥ 16 and Glasgow coma scale ≤ 12 (288 (70%) vs. 1435 (40%) and 126 (31%) vs. 325 (9%), respectively). The unadjusted 30-day mortality rate was 11.7% for patients managed by the Emergency Medical Retrieval and Transfer Service compared with 9.6% for patients managed by standard pre-hospital care services. However, after adjustment for differences in case-mix, the 30-day mortality rate for patients treated by the Emergency Medical Retrieval and Transfer Service was 37% lower (adjusted odds ratio 0.63 (95%CI 0.41-0.97); p = 0.037). The introduction of an emergency medical retrieval service was associated with a reduction in 30-day mortality for patients with blunt traumatic injury.


Asunto(s)
Cuidados Críticos , Servicios Médicos de Urgencia/estadística & datos numéricos , Heridas y Lesiones/patología , Adolescente , Adulto , Anciano , Niño , Preescolar , Bases de Datos Factuales , Femenino , Escala de Coma de Glasgow , Humanos , Lactante , Recién Nacido , Modelos Logísticos , Masculino , Persona de Mediana Edad , Médicos/psicología , Sistema de Registros , Estudios Retrospectivos , Factores de Tiempo , Gales , Heridas y Lesiones/mortalidad , Adulto Joven
7.
Photochem Photobiol Sci ; 19(2): 171-179, 2020 Feb 19.
Artículo en Inglés | MEDLINE | ID: mdl-31942903

RESUMEN

Nicotinamide (NAM), an amide form of vitamin B3, replenishes cellular energy after ultraviolet radiation (UVR) exposure, thereby enhancing DNA repair and reducing UVR's immunosuppressive effects. NAM reduces actinic keratoses and new keratinocyte cancers in high risk individuals, but its effects on melanoma are unknown. Melanomas arising on NAM or placebo within the ONTRAC skin cancer chemoprevention trial (Oral Nicotinamide To Reduce Actinic Cancer) were examined by immunohistochemistry. The effects of NAM (50 µM, 5 mM and 20 mM) on the viability, proliferation and invasiveness of four human melanoma cell lines and on the viability and proliferation of two human melanocyte lines, with and without UV irradiation were also investigated. 50 µM NAM did not affect viability, proliferation or invasion of melanoma or melanocyte cell lines, whereas concentrations too high to be achievable in vivo reduced viability and proliferation. Nicotinamide did not enhance melanoma viability, proliferation or invasiveness in vitro, providing additional confidence in its safety for use in clinical trials in high risk patients. Peritumoral and tumour infiltrating CD4+ and CD8+ lymphocytes were significantly increased in melanomas arising on NAM compared to those arising on placebo. Given the chemopreventive activity of nicotinamide against keratinocyte cancers, its DNA repair enhancing effects in melanocytes and now its potential enhancement of tumour-infiltrating lymphocytes and lack of adverse effects on melanoma cell growth and proliferation, clinical trials of nicotinamide for melanoma chemoprevention are now indicated.


Asunto(s)
Melanoma/patología , Niacinamida/farmacología , Neoplasias Cutáneas/patología , Linfocitos T CD4-Positivos/citología , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/citología , Linfocitos T CD8-positivos/inmunología , Línea Celular Tumoral , Movimiento Celular/efectos de los fármacos , Supervivencia Celular/efectos de los fármacos , Humanos , Melanoma/tratamiento farmacológico , Melanoma/prevención & control , Niacinamida/química , Niacinamida/uso terapéutico , Neoplasias Cutáneas/tratamiento farmacológico , Rayos Ultravioleta
8.
J Chem Phys ; 148(24): 244302, 2018 Jun 28.
Artículo en Inglés | MEDLINE | ID: mdl-29960347

RESUMEN

Photoabsorption cross sections and oscillator strengths for the strong, predissociating vibrational bands, v ≥ 11, in the S2 BΣu-3-XΣg-3(v,0) system are reported. Absorption measurements were undertaken on S2 vapor produced by a radio-frequency discharge through H2S seeded in helium, and also in a two-temperature sulfur furnace, at temperatures of 370 K and 823 K, respectively. S2 column densities were determined in each source by combining experimental line strengths in low-v non-predissociating B - X bands (v < 7) with calculated line f-values based on measured radiative lifetimes and calculated branching ratios. The broad-band capabilities of two vacuum-ultraviolet Fourier-transform spectrometers, used with instrumental resolutions of 0.22 cm-1 and 0.12 cm-1, respectively, allowed for simultaneous recordings of both non-predissociating and predissociating bands, thus placing the predissociating-band cross sections on a common absolute scale. Uncertainties in the final cross section datasets are estimated to be 15% for the 370-K vapor and 10% for the 823-K vapor. The experimental cross sections are used to inform a detailed predissociation model of the B(v) levels in Paper II [Lewis et al., J. Chem. Phys. 148, 244303 (2018)]. For astrophysical and other applications, this model can be adjusted simply to provide isotopologue-specific cross sections for a range of relevant temperatures.

10.
Am J Pathol ; 186(7): 1847-1860, 2016 07.
Artículo en Inglés | MEDLINE | ID: mdl-27182643

RESUMEN

Loss of E-cadherin marks a defect in epithelial integrity and polarity during tissue injury and fibrosis. Whether loss of E-cadherin plays a causal role in fibrosis is uncertain. α3ß1 Integrin has been identified to complex with E-cadherin in cell-cell adhesion, but little is known about the details of their cross talk. Herein, E-cadherin gene (Cdh1) was selectively deleted from proximal tubules of murine kidney by Sglt2Cre. Ablation of E-cadherin up-regulated α3ß1 integrin at cell-cell adhesion. E-cadherin-deficient proximal tubular epithelial cell displayed enhanced transforming growth factor-ß1-induced α-smooth muscle actin (α-SMA) and vimentin expression, which was suppressed by siRNA silencing of α3 integrin, but not ß1 integrin. Up-regulation of transforming growth factor-ß1-induced α-SMA was mediated by an α3 integrin-dependent increase in integrin-linked kinase (ILK). Src phosphorylation of ß-catenin and consequent p-ß-catenin-Y654/p-Smad2 transcriptional complex underlies the transcriptional up-regulation of ILK. Kidney fibrosis after unilateral ureteric obstruction or ischemia reperfusion was increased in proximal tubule E-cadherin-deficient mice in comparison to that of E-cadherin intact control mice. The exacerbation of fibrosis was explained by the α3 integrin-dependent increase of ILK, ß-catenin nuclear translocation, and α-SMA/proximal tubular-specific Cre double positive staining in proximal tubular epithelial cell. These studies delineate a nonconventional integrin/ILK signaling by α3 integrin-dependent Src/p-ß-catenin-Y654/p-Smad2-mediated up-regulation of ILK through which loss of E-cadherin leads to kidney fibrosis.


Asunto(s)
Cadherinas/deficiencia , Integrina alfa3beta1/metabolismo , Enfermedades Renales/patología , Proteínas Serina-Treonina Quinasas/metabolismo , Animales , Western Blotting , Adhesión Celular , Inmunoprecipitación de Cromatina , Modelos Animales de Enfermedad , Fibrosis/metabolismo , Fibrosis/patología , Inmunohistoquímica , Inmunoprecipitación , Enfermedades Renales/metabolismo , Túbulos Renales Proximales/metabolismo , Túbulos Renales Proximales/patología , Ratones , Ratones Noqueados , Microscopía Electrónica de Transmisión , Reacción en Cadena en Tiempo Real de la Polimerasa , Transducción de Señal/fisiología
11.
Theor Appl Genet ; 130(10): 2069-2090, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28707249

RESUMEN

KEY MESSAGE: QTL consistent across seasons were detected for resistance to cassava brown streak disease induced root necrosis and foliar symptoms. The CMD2 locus was detected in an East African landrace, and comprised two QTL. Cassava production in Africa is compromised by cassava brown streak disease (CBSD) and cassava mosaic disease (CMD). To reduce costs and increase the precision of resistance breeding, a QTL study was conducted to identify molecular markers linked to resistance against these diseases. A bi-parental F1 mapping population was developed from a cross between the Tanzanian farmer varieties, Namikonga and Albert. A one-step genetic linkage map comprising 943 SNP markers and 18 linkage groups spanning 1776.2 cM was generated. Phenotypic data from 240 F1 progeny were obtained from two disease hotspots in Tanzania, over two successive seasons, 2013 and 2014. Two consistent QTLs linked to resistance to CBSD-induced root necrosis were identified in Namikonga on chromosomes II (qCBSDRNFc2Nm) and XI (qCBSDRNc11Nm) and a putative QTL on chromosome XVIII (qCBSDRNc18Nm). qCBSDRNFc2Nm was identified at Naliendele in both seasons. The same QTL was also associated with CBSD foliar resistance. qCBSDRNc11Nm was identified at Chambezi in both seasons, and was characterized by three peaks, spanning a distance of 253 kb. Twenty-seven genes were identified within this region including two LRR proteins and a signal recognition particle. In addition, two highly significant CMD resistance QTL (qCMDc12.1A and qCMDc12.2A) were detected in Albert, on chromosome 12. Both qCMDc12.1A and qCMDc12.2A lay within the range of markers reported earlier, defining the CMD2 locus. This is the first time that two loci have been identified within the CMD2 QTL, and in germplasm of apparent East African origin. Additional QTLs with minor effects on CBSD and CMD resistance were also identified.


Asunto(s)
Resistencia a la Enfermedad/genética , Manihot/genética , Enfermedades de las Plantas/genética , Sitios de Carácter Cuantitativo , Mapeo Cromosómico , Ligamiento Genético , Genotipo , Manihot/microbiología , Fenotipo , Enfermedades de las Plantas/microbiología , Polimorfismo de Nucleótido Simple , Tanzanía
12.
Nature ; 478(7367): 93-6, 2011 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-21979050

RESUMEN

The snowball Earth hypothesis postulates that the planet was entirely covered by ice for millions of years in the Neoproterozoic era, in a self-enhanced glaciation caused by the high albedo of the ice-covered planet. In a hard-snowball picture, the subsequent rapid unfreezing resulted from an ultra-greenhouse event attributed to the buildup of volcanic carbon dioxide (CO(2)) during glaciation. High partial pressures of atmospheric CO(2) (pCO2; from 20,000 to 90,000 p.p.m.v.) in the aftermath of the Marinoan glaciation (∼635 Myr ago) have been inferred from both boron and triple oxygen isotopes. These pCO2 values are 50 to 225 times higher than present-day levels. Here, we re-evaluate these estimates using paired carbon isotopic data for carbonate layers that cap Neoproterozoic glacial deposits and are considered to record post-glacial sea level rise. The new data reported here for Brazilian cap carbonates, together with previous ones for time-equivalent units, provide estimates lower than 3,200 p.p.m.v.--and possibly as low as the current value of ∼400 p.p.m.v. Our new constraint, and our re-interpretation of the boron and triple oxygen isotope data, provide a completely different picture of the late Neoproterozoic environment, with low atmospheric concentrations of carbon dioxide and oxygen that are inconsistent with a hard-snowball Earth.

13.
Ann Oncol ; 27(2): 294-9, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26578732

RESUMEN

BACKGROUND: Pre-treatment lymphocytopaenia may result from cytokines secreted by the tumour microenvironment in association with aggressive tumour biology. We sought to establish the prognostic significance of lymphocytopaenia in muscle-invasive and advanced bladder cancer. PATIENTS AND METHODS: Seventy-four patients with muscle-invasive bladder cancer treated with radical chemoradiotherapy and 131 patients with advanced bladder cancer treated with palliative chemotherapy were included in the study. The absolute lymphocyte count on the first day of treatment was recorded. Invasive local or systemic recurrence in the muscle-invasive bladder cancer cohort and all-cause mortality in the advanced bladder cancer cohort were defined as survival end points. Receiver operating characteristic (ROC) curve analysis was utilized to determine the cut-off for defining lymphocytopaenia in the muscle-invasive bladder cancer cohort followed by multivariable analysis in a model evaluating the following variables: anaemia, neutrophilia, tumour stage, hydronephrosis and neoadjuvant chemotherapy. Subsequently, lymphocytopaenia was assessed in a multivariable model of the advanced bladder cancer cohort analysing the following prognostic variables: neutrophilia, anaemia, performance status and presence of bone or visceral metastases. A further analysis was carried out evaluating absolute lymphocyte count as a continuous variable. RESULTS: An absolute lymphocyte count of 1.5 × 10(9)/l was determined as the cut-off on ROC curve analysis in the muscle-invasive bladder cancer cohort, and multivariate analysis revealed that only lymphocytopaenia was predictive for inferior outcome in this cohort. In the advanced bladder cancer cohort, lymphocytopaenia [hazard ratio (HR) 1.6, 95% confidence interval (CI) 1.1-2.4; P = 0.02] and performance status (HR 1.7, 95% CI 1.0-2.7; P = 0.047) were adverse prognostic factors in the binary variable multivariate model. Absolute lymphocyte count was the sole significant factor when analysed as a continuous variable (HR 0.66, 95% CI 0.5-0.87; P = 0.003). CONCLUSION: Pre-treatment lymphocytopaenia is an independent adverse prognostic factor in both muscle-invasive and advanced bladder cancer. It may be a manifestation of cancer-induced immune suppression driving tumour progression.


Asunto(s)
Biomarcadores de Tumor/sangre , Neoplasias Óseas/secundario , Linfopenia/patología , Neoplasias de los Músculos/secundario , Neoplasias de la Vejiga Urinaria/patología , Anciano , Anciano de 80 o más Años , Anemia/complicaciones , Quimioradioterapia , Estudios de Cohortes , Femenino , Humanos , Hidronefrosis/complicaciones , Recuento de Linfocitos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/patología , Neutrófilos/inmunología , Pronóstico , Curva ROC , Microambiente Tumoral , Vejiga Urinaria/patología , Neoplasias de la Vejiga Urinaria/mortalidad , Neoplasias de la Vejiga Urinaria/terapia
14.
Metab Eng ; 38: 105-114, 2016 11.
Artículo en Inglés | MEDLINE | ID: mdl-27445159

RESUMEN

Heparin is a carbohydrate anticoagulant used clinically to prevent thrombosis, however impurities can limit its efficacy. Here we report the biosynthesis of heparin-like heparan sulfate via the recombinant expression of human serglycin in human cells. The expressed serglycin was also decorated with chondroitin/dermatan sulfate chains and the relative abundance of these glycosaminoglycan chains changed under different concentrations of glucose in the culture medium. The recombinantly expressed serglycin produced with 25mM glucose present in the culture medium was found to possess anticoagulant activity one-seventh of that of porcine unfractionated heparin, demonstrating that bioengineered human heparin-like heparan sulfate may be a safe next-generation pharmaceutical heparin.


Asunto(s)
Coagulación Sanguínea/efectos de los fármacos , Ingeniería Genética/métodos , Heparina/análogos & derivados , Proteoglicanos/administración & dosificación , Proteoglicanos/biosíntesis , Proteínas de Transporte Vesicular/administración & dosificación , Proteínas de Transporte Vesicular/biosíntesis , Anticoagulantes/administración & dosificación , Anticoagulantes/metabolismo , Células HEK293 , Heparina/administración & dosificación , Heparina/biosíntesis , Heparina/genética , Humanos , Ingeniería Metabólica , Proteoglicanos/genética , Proteínas de Transporte Vesicular/genética
15.
Stem Cells ; 33(1): 157-69, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24966117

RESUMEN

Stem cell (SC) division, deployment, and differentiation are processes that contribute to corneal epithelial renewal. Until now studying the destiny of these cells in a living mammal has not been possible. However, the advent of inducible multicolor genetic tagging and powerful imaging technologies has rendered this achievable in the translucent and readily accessible murine cornea. K14CreER(T2)-Confetti mice that harbor two copies of the Brainbow 2.1 cassette, yielding up to 10 colors from the stochastic recombination of fluorescent proteins, were used to monitor K-14(+) progenitor cell dynamics within the corneal epithelium in live animals. Multicolored columns of cells emerged from the basal limbal epithelium as they expanded and migrated linearly at a rate of 10.8 µm/day toward the central cornea. Moreover, the permanent expression of fluorophores, passed on from progenitor to progeny, assisted in discriminating individual clones as spectrally distinct streaks containing more than 1,000 cells within the illuminated area. The centripetal clonal expansion is suggestive that a single progenitor cell is responsible for maintaining a narrow corridor of corneal epithelial cells. Our data are in agreement with the limbus as the repository for SC as opposed to SC being distributed throughout the central cornea. This is the first report describing stem/progenitor cell fate determination in the murine cornea using multicolor genetic tracing. This model represents a powerful new resource to monitor SC kinetics and fate choice under homeostatic conditions, and may assist in assessing clonal evolution during corneal development, aging, wound-healing, disease, and following transplantation.


Asunto(s)
Córnea/citología , Epitelio Corneal/citología , Células Madre/citología , Animales , Diferenciación Celular/fisiología , Córnea/metabolismo , Células Epiteliales/citología , Células Epiteliales/metabolismo , Epitelio Corneal/metabolismo , Ratones , Ratones Endogámicos BALB C , Ratones Endogámicos C57BL , Células Madre/metabolismo
16.
AIDS Behav ; 20(8): 1621-31, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-26860536

RESUMEN

Screening for HIV-associated neurocognitive disorders (HAND) is important to improve clinical outcomes. We compared the diagnostic sensitivity and specificity of the mini-mental state examination, International HIV dementia scale (IHDS), Montreal cognitive assessment, Simioni symptom questionnaire and cognitive assessment tool-rapid version (CAT-rapid) to a gold standard neuropsychological battery. Antiretroviral-experienced participants from Cape Town, South Africa, and Baltimore, USA, were recruited. The sensitivity and specificity of the five tools, as well as those of the combined IHDS and CAT-rapid, were established using 2 × 2 contingency tables and ROC analysis. More than a third (65165) had symptomatic HAND. In detecting HIV-D, the CAT-Rapid had good sensitivity (94 %) and weak specificity (52 %) (cut-point ≤10), while the IHDS showed fair sensitivity (68 %) and good specificity (86 %) (cut-point ≤10). The combined IHDS and CAT-rapid showed excellent sensitivity and specificity for HIV-D at a cut-off score of ≤16 (out of 20; 89 and 82 %). No tool was adequate in screening for any HAND. The combination IHDS and CAT-rapid tool appears to be a good screener for HIV-D but is only fairly sensitive and poorly specific in screening for any HAND. Screening for milder forms of HAND continues to be a clinical challenge.


Asunto(s)
Complejo SIDA Demencia/diagnóstico , Comparación Transcultural , Infecciones por VIH/complicaciones , Tamizaje Masivo/instrumentación , Encuestas y Cuestionarios/normas , Complejo SIDA Demencia/psicología , Baltimore , Trastornos del Conocimiento/diagnóstico , Femenino , Infecciones por VIH/psicología , Humanos , Masculino , Tamizaje Masivo/métodos , Pruebas Neuropsicológicas , Valor Predictivo de las Pruebas , Curva ROC , Sensibilidad y Especificidad , Índice de Severidad de la Enfermedad , Sudáfrica
17.
J Cell Sci ; 126(Pt 1): 67-76, 2013 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23203799

RESUMEN

Transforming growth factor ß1 (TGF-ß1) is known to be both anti-inflammatory and profibrotic. Cross-talk between TGF-ß/Smad and Wnt/ß-catenin pathways in epithelial-mesenchymal transition (EMT) suggests a specific role for ß-catenin in profibrotic effects of TGF-ß1. However, no such mechanistic role has been demonstrated for ß-catenin in the anti-inflammatory effects of TGF-ß1. In the present study, we explored the role of ß-catenin in the profibrotic and anti-inflammatory effects of TGF-ß1 by using a cytosolic, but not membrane, ß-catenin knockdown chimera (F-TrCP-Ecad) and the ß-catenin/CBP inhibitor ICG-001. TGF-ß1 induced nuclear Smad3/ß-catenin complex, but not ß-catenin/LEF-1 complex or TOP-flash activity, during EMT of C1.1 (renal tubular epithelial) cells. F-TrCP-Ecad selectively degraded TGF-ß1-induced cytoplasmic ß-catenin and blocked EMT of C1.1 cells. Both F-TrCP-Ecad and ICG-001 blocked TGF-ß1-induced Smad3/ß-catenin and Smad reporter activity in C1.1 cells, suggesting that TGF-ß1-induced EMT depends on ß-catenin binding to Smad3, but not LEF-1 downstream of Smad3, through canonical Wnt. In contrast, in J774 macrophages, the ß-catenin level was low and was not changed by interferon-γ (IFN-γ) or lipopolysaccharide (LPS) with or without TGF-ß1. TGF-ß1 inhibition of LPS-induced TNF-α and IFN-γ-stimulated inducible NO synthase (iNOS) expression was not affected by F-TrCP-Ecad, ICG-001 or by overexpression of wild-type ß-catenin in J774 cells. Inhibition of ß-catenin by either F-TrCP-Ecad or ICG-001 abolished LiCl-induced TOP-flash, but not TGF-ß1-induced Smad reporter, activity in J774 cells. These results demonstrate for the first time that ß-catenin is required as a co-factor of Smad in TGF-ß1-induced EMT of C1.1 epithelial cells, but not in TGF-ß1 inhibition of macrophage activation. Targeting ß-catenin may dissociate the TGF-ß1 profibrotic and anti-inflammatory effects.


Asunto(s)
Antiinflamatorios/farmacología , Factor de Unión 1 al Potenciador Linfoide/metabolismo , Proteína smad3/metabolismo , Factor de Crecimiento Transformador beta1/farmacología , beta Catenina/metabolismo , Animales , Western Blotting , Línea Celular , Transición Epitelial-Mesenquimal/efectos de los fármacos , Transición Epitelial-Mesenquimal/genética , Inmunoprecipitación , Factor de Unión 1 al Potenciador Linfoide/genética , Ratones , Microscopía Fluorescente , Unión Proteica/efectos de los fármacos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteína smad3/genética , beta Catenina/genética
18.
Child Care Health Dev ; 41(6): 954-62, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26010416

RESUMEN

BACKGROUND: Urinary incontinence is frequently experienced by children with spina bifida, putting them at increased risk for low self-esteem and impacting upon participation in home, school and leisure activities. However, little is known about children's experiences of these continence issues. OBJECTIVE: This study explored the experiences of children and young people with spina bifida around continence issues, social participation and peer relationships, in order to identify potential areas of support healthcare professionals can provide. METHODS: Children and youth aged 6-18 years with diagnoses of spina bifida and neurogenic bladder and their parents were invited to participate in semi-structured interviews. Descriptive thematic analysis was employed. RESULTS: Eleven children (with a range of mobility levels, types of spina bifida and degrees of bladder control) and their parents participated in the study. Three broad themes were identified, which encompassed the following: (1) normal versus different; (2) independence, ownership and the road to continence; and (3) peer relationships and acceptance. DISCUSSION: The experiences discussed by the children and parents in this study ranged from minimal impact of incontinence on their day-to-day living to significant social isolation and rejection. The stigma of incontinence was apparent in all interviews. Children and youth who were able to control their bladder with minimal accidents had greater independence and more opportunities for social participation. Healthcare professionals need to take into account that parents and their children may differ in attitudes and desires about the management of incontinence.


Asunto(s)
Actitud Frente a la Salud , Participación Social , Disrafia Espinal/complicaciones , Incontinencia Urinaria/etiología , Incontinencia Urinaria/psicología , Adolescente , Niño , Femenino , Humanos , Relaciones Interpersonales , Masculino , Ontario , Padres/psicología , Grupo Paritario , Investigación Cualitativa , Autocuidado , Disrafia Espinal/psicología , Disrafia Espinal/rehabilitación , Incontinencia Urinaria/rehabilitación
19.
J Biol Chem ; 288(5): 3289-304, 2013 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-23235151

RESUMEN

Mast cells are derived from hematopoietic progenitors that are known to migrate to and reside within connective and mucosal tissues, where they differentiate and respond to various stimuli by releasing pro-inflammatory mediators, including histamine, growth factors, and proteases. This study demonstrated that primary human mast cells as well as the rat and human mast cell lines, RBL-2H3 and HMC-1, produce the heparan sulfate proteoglycan, perlecan, with a molecular mass of 640 kDa as well as smaller molecular mass species of 300 and 130 kDa. Utilizing domain-specific antibodies coupled with N-terminal sequencing, it was confirmed that both forms contained the C-terminal module of the protein core known as endorepellin, which were generated by mast cell-derived proteases. Domain-specific RT-PCR experiments demonstrated that transcripts corresponding to domains I and V, including endorepellin, were present; however, mRNA transcripts corresponding to regions of domain III were not present, suggesting that these cells were capable of producing spliced forms of the protein core. Fractions from mast cell cultures that were enriched for these fragments were shown to bind endothelial cells via the α(2)ß(1) integrin and stimulate the migration of cells in "scratch assays," both activities of which were inhibited by incubation with either anti-endorepellin or anti-perlecan antibodies. This study shows for the first time that mast cells secrete and process the extracellular proteoglycan perlecan into fragments containing the endorepellin C-terminal region that regulate angiogenesis and matrix turnover, which are both key events in wound healing.


Asunto(s)
Proteoglicanos de Heparán Sulfato/metabolismo , Mastocitos/metabolismo , Neovascularización Fisiológica , Fragmentos de Péptidos/metabolismo , Cicatrización de Heridas , Secuencia de Aminoácidos , Animales , Adhesión Celular , Línea Celular , Movimiento Celular , Vasos Coronarios/citología , Células Endoteliales/citología , Células Endoteliales/metabolismo , Glicosaminoglicanos/biosíntesis , Proteoglicanos de Heparán Sulfato/química , Proteoglicanos de Heparán Sulfato/genética , Proteoglicanos de Heparán Sulfato/aislamiento & purificación , Humanos , Integrina alfa2beta1/metabolismo , Pulmón/citología , Mastocitos/citología , Datos de Secuencia Molecular , Fragmentos de Péptidos/química , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , Estructura Terciaria de Proteína , Proteoglicanos/biosíntesis , ARN Mensajero/genética , ARN Mensajero/metabolismo , Ratas , Proteínas de Transporte Vesicular/biosíntesis
20.
Br J Cancer ; 111(12): 2262-7, 2014 Dec 09.
Artículo en Inglés | MEDLINE | ID: mdl-25393368

RESUMEN

BACKGROUND: AT7519 is a small-molecular inhibitor of multiple cyclin-dependent kinases (CDKs). It shows encouraging anti-cancer activity against multiple cell lines and in tumour xenografts. This phase I study was conducted to evaluate the safety and tolerability of AT7519 given as 1-h intravenous infusion on days 1, 4, 8 and 11 every 3 weeks. METHODS: Patients with advanced refractory solid tumours or non-Hodgkin's lymphoma were enroled. Dose escalation occurred in a 3+3 manner based on toxicity assessment. Pharmacokinetic samples were collected after first AT7519 infusion, whereas pharmacodynamics (PD) samples were obtained in selected patients. RESULTS: Thirty-four patients were enroled, and 32 received study treatments over 4 dose levels. Dose-limiting toxicities included mucositis, febrile neutropenia, rash, fatigue and hypokalemia. The recommended phase II dose (RP2D) was 27.0 mg m(-2). Ten of 19 patients evaluable for efficacy had stable disease as the best response (median duration: 3.3 months; range: 2.5 to 11.1 months). There was no clinically significant QTc prolongation. There was an apparent dose proportional increase in AT7519 exposure. The PD studies showed reduction in markers of CDK activity in selected patients' skin biopsies post treatment. CONCLUSIONS: AT7519, when administered as an intravenous infusion on days 1, 4, 8 and 11, was well tolerated. The RP2D is 27.0 mg m(-2). At this dose level, plasma AT7519 concentrations were above the biologically active concentrations, and preliminary anti-cancer activity was observed in patients. This dosing schedule is being further evaluated in multiple phase II studies.


Asunto(s)
Quinasas Ciclina-Dependientes/antagonistas & inhibidores , Neoplasias/tratamiento farmacológico , Piperidinas/administración & dosificación , Inhibidores de Proteínas Quinasas/administración & dosificación , Pirazoles/administración & dosificación , Adulto , Anciano , Relación Dosis-Respuesta a Droga , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias/enzimología , Neoplasias/metabolismo , Piperidinas/efectos adversos , Piperidinas/farmacocinética , Inhibidores de Proteínas Quinasas/efectos adversos , Inhibidores de Proteínas Quinasas/farmacocinética , Pirazoles/efectos adversos , Pirazoles/farmacocinética
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