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1.
J Anim Sci ; 1022024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38219027

RESUMEN

Six female littermate piglets were used in an experiment to evaluate the mRNA expression in tissues from piglets given one or two 1 mL injections of iron dextran (200 mg Fe/mL). All piglets in the litter were administered the first 1 mL injection < 24 h after birth. On day 7, piglets were paired by weight (mean body weight = 1.72 ±â€…0.13 kg) and one piglet from each pair was randomly selected as control (CON) and the other received a second injection (+Fe). At weaning on day 22, each piglet was anesthetized, and samples of liver and duodenum were taken from the anesthetized piglets and preserved until mRNA extraction. differential gene expression data were analyzed with a fold change cutoff (FC) of |1.2| P < 0.05. Pathway analysis was conducted with Z-score cutoff of P < 0.05. In the duodenum 435 genes were significantly changed with a FC ≥ |1.2| P < 0.05. In the duodenum, Claudin 1 and Claudin 2 were inversely affected by + Fe. Claudin 1 (CLDN1) plays a key role in cell-to-cell adhesion in the epithelial cell sheets and was upregulated (FC = 4.48, P = 0.0423). Claudin 2 (CLDN2) is expressed in cation leaky epithelia, especially during disease or inflammation and was downregulated (FC = -1.41, P = 0.0097). In the liver, 362 genes were expressed with a FC ≥ |1.2| P < 0.05. The gene most affected by a second dose of 200 mg Fe was hepcidin antimicrobial peptide (HAMP) with a FC of 40.8. HAMP is a liver-produced hormone that is the main circulating regulator of Fe absorption and distribution across tissues. It also controls the major flows of Fe into plasma by promoting endocytosis and degradation of ferroportin (SLC4A1). This leads to the retention of Fe in Fe-exporting cells and decreased flow of Fe into plasma. Gene expression related to metabolic pathway changes in the duodenum and liver provides evidence for the improved feed conversion and growth rates in piglets given two iron injections preweaning with contemporary pigs in a companion study. In the duodenum, there is a downregulation of gene clusters associated with gluconeogenesis (P < 0.05). Concurrently, there was a decrease in the mRNA expression of genes for enzymes required for urea production in the liver (P < 0.05). These observations suggest that there may be less need for gluconeogenesis, and possibly less urea production from deaminated amino acids. The genomic and pathway analyses provided empirical evidence linking gene expression with phenotypic observations of piglet health and growth improvements.


Iron deficiency anemia (IDA) in neonatal piglets is a problem that occurs unless there is intervention with exogenous iron. The most common method to prevent IDA is with an iron injection within 48 h of birth. However, the iron from the first injection will only support normal iron status in the piglets for ~4 kg of growth. As a result, with faster-growing piglets and larger litters, many piglets weaned today are iron deficient which results in slower growth and poor immunity. Pigs never fully recover nor grow at the same rate as those that have sufficient iron status. The aim of this study was to evaluate the effects of one or two injections of iron dextran on the differences in gene expression and metabolic pathway changes in the small intestine and liver of nursing piglets. At weaning, samples of liver and duodenum underwent genome-wide RNA sequencing. The data obtained were statistically analyzed to determine which genes and metabolic pathways were affected. There were 362 and 435 genes significantly changed in the liver and duodenum, respectively, due to a second dose of iron dextran on day 7 after birth.


Asunto(s)
Dextranos , Hierro , Animales , Femenino , Porcinos , Hierro/metabolismo , Destete , Dextranos/metabolismo , Claudina-1/metabolismo , Claudina-2/metabolismo , Lactancia , Complejo Hierro-Dextran , Hígado/metabolismo , Duodeno/metabolismo , ARN Mensajero/metabolismo , Urea/metabolismo , Expresión Génica
2.
Front Oncol ; 13: 1260411, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37817767

RESUMEN

Primary lung carcinoma or lung cancer (LC) is classified into small-cell or non-small-cell (NSCLC) lung carcinoma. Lung squamous cell carcinoma (LSCC) is the second most common subtype of NSCLC responsible for 30% of all LCs, and its survival remains low with only 24% of patients living for five years or longer post-diagnosis primarily due to the advanced stage of tumors at the time of diagnosis. The pathogenesis of LSCC is still poorly understood and has hampered the development of effective diagnostics and therapies. This review highlights the known risk factors, genetic and epigenetic alterations, miRNA biomarkers linked to the development and diagnosis of LSCC and the lack of therapeutic strategies to target specifically LSCC. We will also discuss existing animal models of LSCC including carcinogen induced, transgenic and xenograft mouse models, and their advantages and limitations along with the chemopreventive studies and molecular studies conducted using them. The importance of developing new and improved mouse models will also be discussed that will provide further insights into the initiation and progression of LSCC, and enable the identification of new biomarkers and therapeutic targets.

4.
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
5.
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.

6.
Clin Oncol (R Coll Radiol) ; 34(7): e291-e297, 2022 07.
Artículo en Inglés | MEDLINE | ID: mdl-35314092

RESUMEN

AIMS: We conducted a pooled analysis of four randomised controlled trials and a non-trial retrospective dataset to study the changes in serum prostate-specific antigen (PSA) concentrations during treatment and its impact on survival in men treated with docetaxel for metastatic castration-resistant prostate cancer. We also compared the outcomes and pre-treatment prognostic factors between trial and non-trial patients. MATERIALS AND METHODS: Data were obtained from four randomised controlled trials and a non-trial cohort from a tertiary cancer centre. The PSA kinetics covariates chosen were absolute value (PSAT), best percentage change (BPCH) and tumour growth rate (K). The association between the covariates collected and overall survival was assessed within a Cox proportional hazards model. How well a covariate captured the difference between trial and non-trial patients was assessed by reporting on models with or without trial status as a covariate. RESULTS: We reviewed individual datasets of 2282 patients. The median overall survival for trial patients was 20.4 (95% confidence interval 19.6-22.2) months and for the non-trial cohort was 12.4 (10.7-14.7) months (P < 0.001). Of the pre-treatment factors, we found that only lactate dehydrogenase fully captured the difference in prognosis between the trial and non-trial cohorts. All PSA kinetic metrics appeared to be prognostic in both the trial and non-trial patients. However, the effect size was reduced in non-trial versus trial patients (interaction P < 0.001). Of the time-dependent covariates, we found that BPCH best captured the difference between trial and non-trial patient prognosis. CONCLUSIONS: The analysis presented here highlights how data from open-source trial databases can be combined with emerging clinical practice databases to assess differences between trial versus non-trial patients for particular treatments. These results highlight the importance of developing prognostic models using both pre-treatment and time-dependent biomarkers of new treatments.


Asunto(s)
Docetaxel , Neoplasias de la Próstata Resistentes a la Castración , Docetaxel/uso terapéutico , Humanos , Masculino , Pronóstico , Antígeno Prostático Específico , Neoplasias de la Próstata Resistentes a la Castración/tratamiento farmacológico , Neoplasias de la Próstata Resistentes a la Castración/patología , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Retrospectivos , Taxoides/uso terapéutico , Resultado del Tratamiento
7.
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
8.
Sci Adv ; 7(40): eabh0363, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34586840

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic, chemoresistant malignancy and is characterized by a dense, desmoplastic stroma that modulates PDAC progression. Here, we visualized transient manipulation of focal adhesion kinase (FAK), which integrates bidirectional cell-environment signaling, using intravital fluorescence lifetime imaging microscopy of the FAK-based Förster resonance energy transfer biosensor in mouse and patient-derived PDAC models. Parallel real-time quantification of the FUCCI cell cycle reporter guided us to improve PDAC response to standard-of-care chemotherapy at primary and secondary sites. Critically, micropatterned pillar plates and stiffness-tunable matrices were used to pinpoint the contribution of environmental cues to chemosensitization, while fluid flow­induced shear stress assessment, patient-derived matrices, and personalized in vivo models allowed us to deconstruct how FAK inhibition can reduce PDAC spread. Last, stratification of PDAC patient samples via Merlin status revealed a patient subset with poor prognosis that are likely to respond to FAK priming before chemotherapy.

9.
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
10.
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
11.
Geochim Cosmochim Acta ; 282: 177-200, 2020 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-33005059

RESUMEN

Isotope fractionation due to photochemical self-shielding is believed to be responsible for the enrichment of inner solar system planetary materials in the rare isotopes of carbon, nitrogen, and oxygen relative to the Sun. Self-shielding may also contribute to sulfur isotope mass-independent fractionation in modern atmospheric sulfates, although its role in the early Earth atmosphere has not yet been convincingly established. Here, I present an analytical formulation of isotopic photodissociation rate coefficients that describe self-shielding isotope signatures for 3 and 4-isotope systems broadly representative of O and S isotopes. The analytic equations are derived for idealized molecular spectra, making an analytic formulation tractable. The idealized spectra characterize key features of actual isotopologue spectra, particularly for CO and SO2, but are applicable to many small molecules and their isotopologues. The analytic expressions are convenient for evaluating the magnitude of isotope effects without having to pursue involved numerical solutions. More importantly, the analytic expressions illustrate the origin of particular isotope signatures, such as the previously unexplained large mass-dependent fractionation associated with photodissociation of optically-thick SO2. The formulation presented here elucidates the origin of some of these important isotopic fractionation processes.

12.
Mucosal Immunol ; 13(6): 877-891, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32820248

RESUMEN

COVID-19 is causing a major once-in-a-century global pandemic. The scientific and clinical community is in a race to define and develop effective preventions and treatments. The major features of disease are described but clinical trials have been hampered by competing interests, small scale, lack of defined patient cohorts and defined readouts. What is needed now is head-to-head comparison of existing drugs, testing of safety including in the background of predisposing chronic diseases, and the development of new and targeted preventions and treatments. This is most efficiently achieved using representative animal models of primary infection including in the background of chronic disease with validation of findings in primary human cells and tissues. We explore and discuss the diverse animal, cell and tissue models that are being used and developed and collectively recapitulate many critical aspects of disease manifestation in humans to develop and test new preventions and treatments.


Asunto(s)
Anticuerpos Antivirales/biosíntesis , Antivirales/farmacología , Betacoronavirus/patogenicidad , Infecciones por Coronavirus/inmunología , Modelos Animales de Enfermedad , Neumonía Viral/inmunología , Vacunas Virales/biosíntesis , Enzima Convertidora de Angiotensina 2 , Animales , Animales Modificados Genéticamente , Antivirales/síntesis química , Betacoronavirus/efectos de los fármacos , Betacoronavirus/genética , Betacoronavirus/fisiología , COVID-19 , Vacunas contra la COVID-19 , Gatos , Quirópteros , Infecciones por Coronavirus/tratamiento farmacológico , Infecciones por Coronavirus/genética , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/virología , Cricetulus , Femenino , Hurones , Haplorrinos , Humanos , Masculino , Ratones , Organoides/efectos de los fármacos , Organoides/inmunología , Organoides/virología , Pandemias , Peptidil-Dipeptidasa A/genética , Peptidil-Dipeptidasa A/inmunología , Neumonía Viral/tratamiento farmacológico , Neumonía Viral/genética , Neumonía Viral/virología , SARS-CoV-2 , Índice de Severidad de la Enfermedad , Especificidad de la Especie , Glicoproteína de la Espiga del Coronavirus/genética , Glicoproteína de la Espiga del Coronavirus/inmunología , Vacunas Virales/administración & dosificación
13.
Cell Rep ; 31(9): 107702, 2020 06 02.
Artículo en Inglés | MEDLINE | ID: mdl-32492418

RESUMEN

To better understand the influence of ultraviolet (UV) irradiation on the initial steps of skin carcinogenesis, we examine patches of labeled keratinocytes as a proxy for clones in the interfollicular epidermis (IFE) and measure their size variation upon UVB irradiation. Multicolor lineage tracing reveals that in chronically irradiated skin, patches near hair follicles (HFs) increase in size, whereas those far from follicles do not change. This is explained by proliferation of basal epidermal cells within 60 µm of HF openings. Upon interruption of UVB, patch size near HFs regresses significantly. These anatomical differences in proliferative behavior have significant consequences for the cell of origin of basal cell carcinomas (BCCs). Indeed, a UV-inducible murine BCC model shows that BCC patches are more frequent, larger, and more invasive near HFs. These findings have major implications for the prevention of field cancerization in the epidermis.


Asunto(s)
Epidermis/metabolismo , Neoplasias Inducidas por Radiación/patología , Rayos Ultravioleta , Animales , Carcinoma Basocelular/metabolismo , Carcinoma Basocelular/patología , Proliferación Celular , Ciclina D1/metabolismo , Modelos Animales de Enfermedad , Epidermis/efectos de la radiación , Folículo Piloso/patología , Ratones , Ratones Endogámicos C57BL , Ratones Transgénicos , Neoplasias Inducidas por Radiación/metabolismo , Neoplasias Cutáneas/metabolismo , Neoplasias Cutáneas/patología , Células Madre/citología , Células Madre/metabolismo , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo
14.
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
15.
Nat Commun ; 10(1): 5546, 2019 12 05.
Artículo en Inglés | MEDLINE | ID: mdl-31804466

RESUMEN

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common cancer worldwide. Tobacco use is the main risk factor for HNSCC, and tobacco-associated HNSCCs have poor prognosis and response to available treatments. Recently approved anti-PD-1 immune checkpoint inhibitors showed limited activity (≤20%) in HNSCC, highlighting the need to identify new therapeutic options. For this, mouse models that accurately mimic the complexity of the HNSCC mutational landscape and tumor immune environment are urgently needed. Here, we report a mouse HNSCC model system that recapitulates the human tobacco-related HNSCC mutanome, in which tumors grow when implanted in the tongue of immunocompetent mice. These HNSCC lesions have similar immune infiltration and response rates to anti-PD-1 (≤20%) immunotherapy as human HNSCCs. Remarkably, we find that >70% of HNSCC lesions respond to intratumoral anti-CTLA-4. This syngeneic HNSCC mouse model provides a platform to accelerate the development of immunotherapeutic options for HNSCC.


Asunto(s)
Carcinoma de Células Escamosas/terapia , Neoplasias de Cabeza y Cuello/terapia , Inmunoterapia/métodos , Ipilimumab/uso terapéutico , Neoplasias de la Boca/terapia , Animales , Antineoplásicos Inmunológicos/uso terapéutico , Carcinoma de Células Escamosas/inducido químicamente , Línea Celular Tumoral , Modelos Animales de Enfermedad , Neoplasias de Cabeza y Cuello/inducido químicamente , Humanos , Ratones , Neoplasias de la Boca/inducido químicamente , Nicotiana/efectos adversos
16.
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.

17.
Science ; 366(6470)2019 12 06.
Artículo en Inglés | MEDLINE | ID: mdl-31806788

RESUMEN

Lava flows present a recurring threat to communities on active volcanoes, and volumetric eruption rate is one of the primary factors controlling flow behavior and hazard. The time scales and driving forces of eruption rate variability, however, remain poorly understood. In 2018, a highly destructive eruption occurred on the lower flank of Kilauea Volcano, Hawai'i, where the primary vent exhibited substantial cyclic eruption rates on both short (minutes) and long (tens of hours) time scales. We used multiparameter data to show that the short cycles were driven by shallow outgassing, whereas longer cycles were pressure-driven surges in magma supply triggered by summit caldera collapse events 40 kilometers upslope. The results provide a clear link between eruption rate fluctuations and their driving processes in the magmatic system.

18.
Vet J ; 250: 1-5, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31383413

RESUMEN

Canine papillomatosis is mainly attributed to papillomavirus infections. Papillomavirus DNA is also frequently identified in healthy skin, and evidence of high papillomavirus diversity complicates this simplistic view of causality. The aim of this study was to determine how frequently canine papillomas contain papillomavirus DNA and express viral protein, and how these factors correlate to the histology and anatomic location. Fifty-three archived, formalin-fixed samples of canine papillomas and eight samples of other proliferative skin lesions from dogs were included. Samples were re-evaluated histologically, tested for papillomavirus L1-antigen using immunohistochemistry, and for papillomavirus DNA with PCR assays and molecular sequencing. Most papillomas from haired skin contained papillomavirus DNA (96%) and antigen (92%). Of oral papillomas, 88% were positive for both papillomavirus DNA and antigen. Approximately 50% of non-papilloma proliferations and papillomas from eyelid/conjunctiva specimens contained viral DNA, but antigen was present in only 12% of eyelid/conjunctiva papillomas and in none of the non-papilloma proliferations. The presence of viral antigen was highly correlated with histological indicators of viral infection, including intranuclear inclusions, koilocytes, cytoplasmatic vacuolation and dysplasia. The viruses found were mainly CPV1 and CPV2. CPV1 dominated in oral infections, while CPV2 dominated in cutaneous endophytic papillomas. Co-infections with CPV1 and CPV2 accounted for about 20% of all detected infections. These results support a role for papillomaviruses in canine cutaneous and oral, exophytic and endophytic papillomas and support previously raised doubts about their role in squamous papillomas from eyelid/conjunctiva specimens.


Asunto(s)
Coinfección/veterinaria , Enfermedades de los Perros/patología , Papiloma/veterinaria , Papillomaviridae/aislamiento & purificación , Infecciones por Papillomavirus/veterinaria , Animales , Coinfección/patología , ADN Viral/análisis , Enfermedades de los Perros/virología , Perros , Papiloma/patología , Papiloma/virología , Papillomaviridae/genética , Infecciones por Papillomavirus/patología , Infecciones por Papillomavirus/virología , Proteínas Virales/análisis
20.
Stem Cell Reports ; 12(1): 14-28, 2019 01 08.
Artículo en Inglés | MEDLINE | ID: mdl-30554917

RESUMEN

It is thought that corneal epithelial injuries resolve by leading-edge cells "sliding" or "rolling" into the wound bed. Here, we challenge this notion and show by real-time imaging that corneal wounds initially heal by "basal cell migration." The K14CreERT2-Confetti multi-colored reporter mouse was employed to spatially and temporally fate-map cellular behavior during corneal wound healing. Keratin-14+ basal epithelia are forced into the wound bed by increased population pressure gradient from the limbus to the wound edge. As the defect resolves, centripetally migrating epithelia decelerate and replication in the periphery is reduced. With time, keratin-14+-derived clones diminish in number concomitant with their expansion, indicative that clonal evolution aligns with neutral drifting. These findings have important implications for the involvement of stem cells in acute tissue regeneration, in key sensory tissues such as the cornea.


Asunto(s)
Células Madre Adultas/metabolismo , Lesiones de la Cornea/metabolismo , Células Epiteliales/metabolismo , Queratina-14/metabolismo , Limbo de la Córnea/metabolismo , Cicatrización de Heridas , Células Madre Adultas/fisiología , Animales , Movimiento Celular , Células Epiteliales/fisiología , Epitelio Corneal/citología , Epitelio Corneal/metabolismo , Femenino , Limbo de la Córnea/citología , Masculino , Ratones , Ratones Endogámicos C57BL
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