Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 92
Filtrar
Más filtros

Intervalo de año de publicación
1.
Proc Natl Acad Sci U S A ; 117(45): 28287-28296, 2020 11 10.
Artículo en Inglés | MEDLINE | ID: mdl-33093209

RESUMEN

Head and neck squamous cell carcinoma (HNSCC) associated with high-risk human papilloma virus (HPV) infection is a growing clinical problem. The WEE1 kinase inhibitor AZD1775 (WEE1i) overrides cell cycle checkpoints and is being studied in HNSCC regimens. We show that the HPV16 E6/E7 oncoproteins sensitize HNSCC cells to single-agent WEE1i treatment through activation of a FOXM1-CDK1 circuit that drives mitotic gene expression and DNA damage. An isogenic cell system indicated that E6 largely accounts for these phenotypes in ways that extend beyond p53 inactivation. A targeted genomic analysis implicated FOXM1 signaling downstream of E6/E7 expression and analyses of primary tumors and The Cancer Genome Atlas (TCGA) data revealed an activated FOXM1-directed promitotic transcriptional signature in HPV+ versus HPV- HNSCCs. Finally, we demonstrate the causality of FOXM1 in driving WEE1i sensitivity. These data suggest that elevated basal FOXM1 activity predisposes HPV+ HNSCC to WEE1i-induced toxicity and provide mechanistic insights into WEE1i and HPV+ HNSCC therapies.


Asunto(s)
Proteínas de Ciclo Celular/efectos de los fármacos , Proteína Forkhead Box M1/metabolismo , Infecciones por Papillomavirus/tratamiento farmacológico , Proteínas Tirosina Quinasas/efectos de los fármacos , Pirazoles/antagonistas & inhibidores , Pirimidinonas/antagonistas & inhibidores , Carcinoma de Células Escamosas de Cabeza y Cuello/tratamiento farmacológico , Proteína Quinasa CDC2/metabolismo , Puntos de Control del Ciclo Celular , Proteínas de Ciclo Celular/metabolismo , Línea Celular Tumoral , Daño del ADN/efectos de los fármacos , Neoplasias de Cabeza y Cuello , Humanos , Proteínas Oncogénicas Virales/metabolismo , Proteínas E7 de Papillomavirus/metabolismo , Proteínas Tirosina Quinasas/metabolismo , Proteínas Represoras/metabolismo , Regulación hacia Arriba
2.
Nanotechnology ; 32(4): 045603, 2021 Jan 22.
Artículo en Inglés | MEDLINE | ID: mdl-33036011

RESUMEN

Turkevich method is one of the most employed techniques to synthesize gold nanoparticles. Despite its simplicity, the mechanism has been an issue of debate over the past years. The general belief is that particles are formed by a classical nucleation and growth theory, originally described by LaMer's model. In the present work, we provide new experimental evidences that supports either LaMer's theory and their detractors. In the former model, it is proposed that particles are generated by a burst nucleation form the initial 'seeds', from which their growth in a second and quasi-independent step. Instead, our experiments (DLS, UV/VIS and TEM measurements) support the idea that nanoparticles 'seeds' tend to form large intermediate clusters at the beginning of the synthesis, that afterwards disassemble to yield the final nanoparticles. However, unlike other reports, we propose that during the cluster formation the particles do not coalesce, instead they come close to each other without losing their identity. As the synthesis continues, these clusters are progressively separated into the final particles. As a consequence, a path to synthesize ultra-narrow size nanoparticles is provided, along with their stability against salt aggregation, and shelf-time. We found that these ultra-homogeneous nanoparticles are stable for several months, making them suitable for many applications in the biomedical and analytical research.

3.
Lancet Oncol ; 18(7): e405-e413, 2017 07.
Artículo en Inglés | MEDLINE | ID: mdl-28677576

RESUMEN

Head and neck cancer surgery is often a complex multi-step procedure that includes major resections, vascularised tissue reconstruction, and extensive neck dissection. The upper aerodigestive tract mucosal lining is often disrupted during surgery, which requires the management of a clean-contaminated field and the need to reconstruct the mucosal lining. With bacterial contamination, surgical site infections (SSI) are a serious complication that can result in delayed wound healing, wound breakdown, fistula formation, and compromised tissue reconstruction. Methods to reduce SSI in patients with head and neck cancer have been intensely researched, yielding evolving and varied practice patterns. In this Review, we outline the data supporting perioperative antibiotic prophylaxis for clean-contaminated surgeries, which suggest that clindamycin is an inadequate prophylactic antibiotic therapy in the reduction of SSI, and that prolonged antibiotic courses have no established benefit. For salvage laryngectomy after radiotherapy with or without chemotherapy, reconstruction with vascularised tissue reduces the frequency and severity of pharyngocutaneous fistula formation. These evidence-based recommendations have been shown to reduce the chance of SSI after head and neck surgery.


Asunto(s)
Antibacterianos/uso terapéutico , Profilaxis Antibiótica , Neoplasias de Cabeza y Cuello/cirugía , Colgajos Quirúrgicos/irrigación sanguínea , Infección de la Herida Quirúrgica/prevención & control , Clindamicina/uso terapéutico , Humanos , Procedimientos de Cirugía Plástica , Factores de Riesgo
4.
PLoS Genet ; 9(1): e1003169, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23341773

RESUMEN

In oral squamous cell carcinoma (OSCC), metastasis to lymph nodes is associated with a 50% reduction in 5-year survival. To identify a metastatic gene set based on DNA copy number abnormalities (CNAs) of differentially expressed genes, we compared DNA and RNA of OSCC cells laser-microdissected from non-metastatic primary tumors (n = 17) with those from lymph node metastases (n = 20), using Affymetrix 250K Nsp single-nucleotide polymorphism (SNP) arrays and U133 Plus 2.0 arrays, respectively. With a false discovery rate (FDR)<5%, 1988 transcripts were found to be differentially expressed between primary and metastatic OSCC. Of these, 114 were found to have a significant correlation between DNA copy number and gene expression (FDR<0.01). Among these 114 correlated transcripts, the corresponding genomic regions of each of 95 transcripts had CNAs differences between primary and metastatic OSCC (FDR<0.01). Using an independent dataset of 133 patients, multivariable analysis showed that the OSCC-specific and overall mortality hazards ratio (HR) for patients carrying the 95-transcript signature were 4.75 (95% CI: 2.03-11.11) and 3.45 (95% CI: 1.84-6.50), respectively. To determine the degree by which these genes impact cell survival, we compared the growth of five OSCC cell lines before and after knockdown of over-amplified transcripts via a high-throughput siRNA-mediated screen. The expression-knockdown of 18 of the 26 genes tested showed a growth suppression ≥ 30% in at least one cell line (P<0.01). In particular, cell lines derived from late-stage OSCC were more sensitive to the knockdown of G3BP1 than cell lines derived from early-stage OSCC, and the growth suppression was likely caused by increase in apoptosis. Further investigation is warranted to examine the biological role of these genes in OSCC progression and their therapeutic potentials.


Asunto(s)
Carcinoma de Células Escamosas , Ganglios Linfáticos , Metástasis Linfática , Neoplasias de la Boca , Pronóstico , Anciano , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Femenino , Regulación Neoplásica de la Expresión Génica , Genómica , Humanos , Ganglios Linfáticos/metabolismo , Ganglios Linfáticos/patología , Metástasis Linfática/genética , Metástasis Linfática/patología , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/genética , Neoplasias de la Boca/patología , Estadificación de Neoplasias , Polimorfismo de Nucleótido Simple , ARN Interferente Pequeño/genética
5.
Cancer ; 119(10): 1845-52, 2013 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-23456789

RESUMEN

BACKGROUND: Given the complexity of management of advanced head and neck squamous cell carcinoma (HNSCC), this study hypothesized that high hospital volume would be associated with receiving National Comprehensive Cancer Network (NCCN) guideline therapy and improved survival in patients with advanced HNSCC. METHODS: The Surveillance, Epidemiology, and End Results (SEER)-Medicare database was used to identify patients with advanced HNSCC. Treatment modalities and survival were determined using Medicare data. Hospital volume was determined by the number of patients with HNSCC treated at each hospital. RESULTS: There were 1195 patients with advanced HNSCC who met inclusion criteria. In multivariable analyses, high hospital volume was not associated with receiving multimodality therapy per NCCN guidelines (odds ratio = 1.02, 95% confidence interval = 0.66-1.60), but showed a nearly significant inverse association with survival in a model adjusted for National Cancer Institute-designated cancer center status, age, sex, race, socioeconomic status, marital status, comorbidity, year of diagnosis, tumor site, and tumor stage (hazard ratio = 0.85, 95% confidence interval = 0.69-1.04). CONCLUSIONS: Medicare patients with advanced HNSCC treated at high-volume hospitals were not more likely to receive NCCN guideline therapy, but had nearly statistically significant better survival, when compared with patients treated at low-volume hospitals. These results suggest that features of high-volume hospitals other than delivery of NCCN guideline therapy influence survival. Cancer 2013. © 2013 American Cancer Society.


Asunto(s)
Carcinoma de Células Escamosas/mortalidad , Neoplasias de Cabeza y Cuello/mortalidad , Hospitales de Alto Volumen/estadística & datos numéricos , Hospitales de Bajo Volumen/estadística & datos numéricos , Servicio de Oncología en Hospital/estadística & datos numéricos , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Carcinoma de Células Escamosas/terapia , Quimioterapia Adyuvante , Femenino , Neoplasias de Cabeza y Cuello/patología , Neoplasias de Cabeza y Cuello/terapia , Hospitales de Alto Volumen/normas , Humanos , Comunicación Interdisciplinaria , Estimación de Kaplan-Meier , Masculino , Medicare , Análisis Multivariante , Oportunidad Relativa , Servicio de Oncología en Hospital/normas , Grupo de Atención al Paciente , Radioterapia Adyuvante , Factores de Riesgo , Programa de VERF , Resultado del Tratamiento , Estados Unidos/epidemiología
6.
Ground Water ; 61(5): 617-625, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37680017

RESUMEN

In this issue paper, the authors refine the definition of water sustainability to account for temporal dynamics and spatial variability, identify specific challenges that must be resolved in the very near future to avoid catastrophic outcomes on levels ranging from economic disruption to survival of mankind, discuss related policy changes and potential effectiveness, and describe several technologies available to achieve water security and sustainability. While water quality certainly poses formidable challenges, in this piece we emphasize and address challenges associated with dynamic water supply availability. Our future as a society will depend upon how well and how rapidly we navigate these challenges in the coming years. As such, the main objective is to encourage private and public sector practitioners to consider revising existing programs, and to update current industry business models in a manner that promotes expedited solutions, alignment of beneficial goals, and motivates the biggest consumers of water to adopt modern data collection and decision support technologies.


Asunto(s)
Agua Subterránea , Abastecimiento de Agua
7.
J Pediatr Gastroenterol Nutr ; 55(6): 679-88, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-22699837

RESUMEN

OBJECTIVES: Variations in chronic illness care are common in our health care system and may lead to suboptimal outcomes. Specifically, inconsistent use and suboptimal medication dosing have been demonstrated in the care of patients with inflammatory bowel disease (IBD). Quality improvement (QI) efforts have improved outcomes in conditions such as asthma and diabetes mellitus, but have not been well studied in IBD. We hypothesized that QI efforts would lead to improved outcomes in our pediatric IBD population. METHODS: A QI team was formed within our IBD center in 2005. By 2007, we began prospectively capturing physician global assessment (PGA) and patient-reported global assessment. Significant QI interventions included creating evidence-based medication guidelines, joining a national QI collaborative, initiation of preclinic planning, and monitoring serum 25-hydroxyvitamin D. RESULTS: From 2007 to 2010, 505 patients have been followed at our IBD center. During this time, the frequency of patients in clinical remission increased from 59% to 76% (P < 0.05), the frequency of patients who report that their global assessment is >7 increased from 69% to 80% (P < 0.05), and the frequency of patients with a Short Pediatric Crohn's Disease Activity Index (sPCDAI) <15 increased from 60% to 77% (P < 0.05). The frequency of repeat steroid use decreased from 17% to 10% (P < 0.05). We observed an association between the use of a vitamin D supplement (P = 0.02), serum 25-hydroxyvitamin D (P < 0.05), and quiescent disease activity. CONCLUSIONS: Our results show that significant improvements in patient outcomes are associated with QI efforts that do not rely on new medication or therapies.


Asunto(s)
Atención a la Salud/normas , Enfermedades Inflamatorias del Intestino/terapia , Mejoramiento de la Calidad , Esteroides/uso terapéutico , Vitamina D/uso terapéutico , Adolescente , Niño , Conducta Cooperativa , Suplementos Dietéticos , Femenino , Guías como Asunto , Humanos , Enfermedades Inflamatorias del Intestino/sangre , Enfermedades Inflamatorias del Intestino/tratamiento farmacológico , Masculino , Estudios Prospectivos , Inducción de Remisión , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Vitamina D/análogos & derivados , Vitamina D/sangre
8.
Oncogene ; 41(24): 3355-3369, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35538224

RESUMEN

The oncogene Ras and the tumor suppressor gene p53 are frequently co-mutated in human cancer and mutations in Ras and p53 can cooperate to generate a more malignant cell state. To discover novel druggable targets for cancers carrying co-mutations in Ras and p53, we performed arrayed, kinome focused siRNA and oncology drug phenotypic screening utilizing a set of syngeneic Ras mutant squamous cell carcinoma (SCC) cell lines that also carried co-mutations in selected p53 pathway genes. These cell lines were derived from SCCs from carcinogen-treated inbred mice which harbored germline deletions or mutations in Trp53, p19Arf, Atm, or Prkdc. Both siRNA and drug phenotypic screening converge to implicate the phosphoinositol kinases, receptor tyrosine kinases, MAP kinases, as well as cell cycle and DNA damage response genes as targetable dependencies in SCC. Differences in functional kinome profiles between Ras mutant cell lines reflect incomplete penetrance of Ras synthetic lethal kinases and indicate that co-mutations cause a rewiring of survival pathways in Ras mutant tumors. This study describes the functional kinomic landscape of Ras/p53 mutant chemically-induced squamous cell carcinoma in both the baseline unperturbed state and following DNA damage and nominates candidate therapeutic targets, including the Nek4 kinase, for further development.


Asunto(s)
Carcinoma de Células Escamosas , Proteína p53 Supresora de Tumor , Proteínas ras , Animales , Carcinoma de Células Escamosas/enzimología , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patología , Línea Celular Tumoral , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Humanos , Ratones , Mutación , ARN Interferente Pequeño , Proteína p53 Supresora de Tumor/genética , Proteína p53 Supresora de Tumor/metabolismo , Proteínas ras/genética
9.
Oral Oncol ; 127: 105774, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-35219073

RESUMEN

The main objective of our study was to understand the impact of immune cell composition and the tumor-reactivity of tumor infiltrating lymphocytes (TIL) in HPV-positive (HPV+) and HPV-negative (HPV-) head and neck squamous cell carcinoma (HNSCC). TIL cultures were established from primary HNSCC tumors, the T cell subsets were phenotypically characterized using flow cytometry, and Interferon (IFN)-γ ELISA assay was used to determine TIL function. NanoString Immune Profiler was used to determine an immune signature by HPV-status, and multiplex immunohistochemistry (MIHC) was used to quantify immune cell distributions and their spatial relationships. Results showed that HPV+ and HPV- HNSCC had similar capacity to expand IFN-γ reactive TIL populations, and these TIL populations had similar characteristics. NanoString analysis revealed increased differential expression of genes related to B cell functions in HPV+ HNSCC, which were significant at a Benjamini-Yekutieli adjusted p-value of < 0.001. MIHC also displayed increased CD8+ T cell and CD19/CD20+ B cell densities in the tumor region of HPV+ HNSCC as opposed to HPV- HNSCC (p < 0.01). Increases in a combined metric of tumor B cell content and stromal plasma cell content was associated with increased progression-free survival in HPV- HNSCC patients treated with immune checkpoint inhibitor therapy (p = 0.03). In summary, TIL populations expanded from HPV+ and HPV- HNSCC displayed similar IFN-γ reactivity. However, we identified a strong B-cell signature present within HPV+ HNSCC, and higher B and plasma cell content associated with improved PFS in HPV- HNSCC patients treated with immune checkpoint inhibitors.


Asunto(s)
Neoplasias de Cabeza y Cuello , Infecciones por Papillomavirus , Neoplasias de Cabeza y Cuello/complicaciones , Humanos , Inmunidad , Linfocitos Infiltrantes de Tumor , Carcinoma de Células Escamosas de Cabeza y Cuello/metabolismo
10.
Cancer Res ; 82(18): 3375-3393, 2022 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-35819261

RESUMEN

Pancreatic ductal adenocarcinoma (PDAC) typically presents as metastatic disease at diagnosis and remains refractory to treatment. Next-generation sequencing efforts have described the genomic landscape, classified molecular subtypes, and confirmed frequent alterations in major driver genes, with coexistent alterations in KRAS and TP53 correlating with the highest metastatic burden and poorest outcomes. However, translating this information to guide therapy remains a challenge. By integrating genomic analysis with an arrayed RNAi druggable genome screen and drug profiling of a KRAS/TP53 mutant PDAC cell line derived from a patient-derived xenograft (PDCL), we identified numerous targetable vulnerabilities that reveal both known and novel functional aspects of pancreatic cancer biology. A dependence on the general transcription and DNA repair factor TFIIH complex, particularly the XPB subunit and the CAK complex (CDK7/CyclinH/MAT1), was identified and further validated utilizing a panel of genomically subtyped KRAS mutant PDCLs. TFIIH function was inhibited with a covalent inhibitor of CDK7/12/13 (THZ1), a CDK7/CDK9 kinase inhibitor (SNS-032), and a covalent inhibitor of XPB (triptolide), which led to disruption of the protein stability of the RNA polymerase II subunit RPB1. Loss of RPB1 following TFIIH inhibition led to downregulation of key transcriptional effectors of KRAS-mutant signaling and negative regulators of apoptosis, including MCL1, XIAP, and CFLAR, initiating caspase-8 dependent apoptosis. All three drugs exhibited synergy in combination with a multivalent TRAIL, effectively reinforcing mitochondrial-mediated apoptosis. These findings present a novel combination therapy, with direct translational implications for current clinical trials on metastatic pancreatic cancer patients. Significance: This study utilizes functional genetic and pharmacological profiling of KRAS-mutant pancreatic adenocarcinoma to identify therapeutic strategies and finds that TFIIH inhibition synergizes with TRAIL to induce apoptosis in KRAS-driven pancreatic cancer.


Asunto(s)
Adenocarcinoma , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Adenocarcinoma/tratamiento farmacológico , Adenocarcinoma/genética , Carcinoma Ductal Pancreático/tratamiento farmacológico , Carcinoma Ductal Pancreático/genética , Quinasas Ciclina-Dependientes/genética , Humanos , Neoplasias Pancreáticas/tratamiento farmacológico , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patología , Proteínas Proto-Oncogénicas p21(ras)/genética , Neoplasias Pancreáticas
11.
J Clin Oncol ; 40(2): 138-149, 2022 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-34699271

RESUMEN

PURPOSE: Definitive or postoperative chemoradiation (CRT) is curative for human papillomavirus-associated (HPV+) oropharynx cancer (OPC) but induces significant toxicity. As a deintensification strategy, we studied primary transoral surgery (TOS) and reduced postoperative radiation therapy (RT) in intermediate-risk HPV+ OPC. METHODS: E3311 is a phase II randomized trial of reduced- or standard-dose postoperative RT for resected stage III-IVa (American Joint Committee on Cancer-seventh edition) HPV+ OPC, determined by pathologic parameters. Primary goals were feasibility of prospective multi-institutional study of TOS for HPV+ OPC, and oncologic efficacy (2-year progression-free survival) of TOS and adjuvant therapy in intermediate-risk patients after resection. TOS plus 50 Gy was considered promising if the lower limit of the exact 90% binomial confidence intervals exceeded 85%. Quality of life and swallowing were measured by functional assessment of cancer therapy-head and neck and MD Anderson Dysphagia Index. RESULTS: Credentialed surgeons performed TOS for 495 patients. Eligible and treated patients were assigned as follows: arm A (low risk, n = 38) enrolled 11%, intermediate risk arms B (50 Gy, n = 100) or C (60 Gy, n = 108) randomly allocated 58%, and arm D (high risk, n = 113) enrolled 31%. With a median 35.2-month follow-up for 359 evaluable (eligible and treated) patients, 2-year progression-free survival Kaplan-Meier estimate is 96.9% (90% CI, 91.9 to 100) for arm A (observation), 94.9% (90% CI, 91.3 to 98.6]) for arm B (50 Gy), 96.0% (90% CI, 92.8 to 99.3) for arm C (60 Gy), and 90.7% (90% CI, 86.2 to 95.4) for arm D (66 Gy plus weekly cisplatin). Treatment arm distribution and oncologic outcome for ineligible or step 2 untreated patients (n = 136) mirrored the 359 evaluable patients. Exploratory comparison of functional assessment of cancer therapy-head and neck total scores between arms B and C is presented. CONCLUSION: Primary TOS and reduced postoperative RT result in outstanding oncologic outcome and favorable functional outcomes in intermediate-risk HPV+ OPC.


Asunto(s)
Antineoplásicos/uso terapéutico , Biomarcadores de Tumor/análisis , Cisplatino/uso terapéutico , Inhibidor p16 de la Quinasa Dependiente de Ciclina/análisis , Neoplasias Orofaríngeas/terapia , Papillomaviridae/aislamiento & purificación , Faringectomía , Radioterapia de Intensidad Modulada , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Adulto , Anciano , Anciano de 80 o más Años , Antineoplásicos/efectos adversos , Quimioradioterapia Adyuvante , Cisplatino/efectos adversos , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neoplasias Orofaríngeas/química , Neoplasias Orofaríngeas/patología , Neoplasias Orofaríngeas/virología , Faringectomía/efectos adversos , Supervivencia sin Progresión , Estudios Prospectivos , Radioterapia de Intensidad Modulada/efectos adversos , Carcinoma de Células Escamosas de Cabeza y Cuello/química , Carcinoma de Células Escamosas de Cabeza y Cuello/patología , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Factores de Tiempo
12.
J Toxicol Environ Health A ; 74(15-16): 1076-86, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21707431

RESUMEN

Mining industry is a vital economic sector for many countries but it is also one of the most hazardous activities, both occupationally and environmentally. Existing studies point to several adverse effects on communities' health living near mines, effects such as mesothelioma and respiratory illnesses. Results achieved in a geochemical sampling campaign undertaken in the vicinity of São Francisco de Assis village showed an anomalous distribution of some heavy metals in soils and waters. To evaluate the effects of mining activities on human health produced by these conditions, a group of 28 individuals from São Francisco de Assis village was examined for some biological endpoints. A nonexposed group (30 individuals) with the same demographic characteristics without exposure to genotoxic compounds was also studied and data obtained from both groups compared. Results of the T-cell receptor mutation assay and micronucleus (MN) test showed significant increases in the frequencies of both mutations and MN in exposed subjects compared to controls. Data obtained in the analysis of the different lymphocyte subsets demonstrated significant decreases in percentages of CD3+ and CD4+ cells, and a significant increase in percentage of CD16/56+ cells, in exposed individuals. The results of the present study indicate an elevated risk of human environmental contamination resulting from mining activities, emphasizing the need to implement preventive measures, remediation, and rehabilitation plans. This would lead to a reduction in cancer risk not only for this particular population but for all populations exposed under similar conditions.


Asunto(s)
Exposición a Riesgos Ambientales/efectos adversos , Monitoreo del Ambiente , Contaminantes Ambientales/toxicidad , Metales Pesados/toxicidad , Minería , Adulto , Anciano , Envejecimiento , Biomarcadores , Estudios de Casos y Controles , Contaminantes Ambientales/química , Femenino , Humanos , Residuos Industriales , Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Pruebas de Mutagenicidad , Portugal , Receptores de Antígenos de Linfocitos T/efectos de los fármacos , Receptores de Antígenos de Linfocitos T/genética , Caracteres Sexuales , Adulto Joven
13.
J Craniofac Surg ; 22(3): 801-4, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21558937

RESUMEN

OBJECTIVES: Defects of the scalp and lateral temporal bone (LTB) represent a unique challenge to the reconstructive surgeon. Simple reconstructive methods such as skin grafts, locoregional flaps, or tissue expanders are often not feasible owing to a myriad of reasons. Vascularized free tissue transfer coverage offers distinct advantages in managing these defects. MATERIALS AND METHODS: A retrospective case series was performed on all patients at the University of Washington Medical Center who had scalp or LTB defects reconstructed with free tissue transfer from May 1996 to July 2009. Cases were analyzed for defect characteristics, flap type, vessel selection, radiation status, dural exposure, complications, and outcomes. RESULTS: A total of 68 free flap reconstructions were performed in 65 patients with scalp or LTB defects. A total of 22 resections included craniotomy, and 48 patients had preoperative or postoperative radiation. Defects ranged from 6 to 836 cm(2). All flaps (46 latissimus, 11 rectus, 4 radial forearm, 6 anterolateral thigh, and 1 omental) were transferred successfully. Vein grafts were required in 5 cases. Complications included delayed flap failure requiring secondary reconstruction, neck hematoma, venous thrombosis, skull base infection, large wound dehiscence, small wound dehiscence, donor site hematoma and seroma, and cerebrospinal fluid leak. Cosmetic results were consistent and durable. CONCLUSIONS: Microvascular free tissue transfer is a safe and reliable method of reconstructing scalp and LTB defects while offering favorable cosmetic results. We favor the use of latissimus muscle-only flap with skin graft coverage for large scalp defects and rectus or anterolateral thigh free flaps for lateral temporal bone defects.


Asunto(s)
Colgajos Tisulares Libres/irrigación sanguínea , Neoplasias de Cabeza y Cuello/cirugía , Osteomielitis/cirugía , Osteorradionecrosis/cirugía , Procedimientos de Cirugía Plástica/métodos , Cuero Cabelludo/cirugía , Hueso Temporal/cirugía , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Craneotomía , Estética , Femenino , Humanos , Masculino , Microcirculación , Persona de Mediana Edad , Complicaciones Posoperatorias , Estudios Retrospectivos
14.
Heliyon ; 7(6): e07392, 2021 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34307927

RESUMEN

The present work addresses some fundamental aspects in the preparation of protein-conjugated gold nanoparticles, in order to ensure an appropriate final product. Ten broadly available and/or easy to implement analytical tools were benchmarked and compared in their capacity to provide reliable and conclusive information for each step of the procedure. These techniques included transmission electron microscopy, UV/VIS spectroscopy, dynamic light scattering, zeta-potential, Fourier-transformed infrared spectroscopy, colloidal stability titration, end-point colloidal stability analysis, cyclic voltammetry, agarose gel electrophoresis and size-exclusion chromatography (SEC). Four different proteins widely used as adaptors or blocking agents were tested, together with 13 nm gold nanoparticles containing different surface chemistries. Among all tested techniques, some of the least popular among nanomaterial scientists probed to be the most informative, including colloidal stability, gel electrophoresis and SEC; the latter being also an efficient purification procedure. These three techniques provide low-cost, low time consuming, sensitive and robust ways to assess the success of the nanoparticle bioconjugation steps, especially when used in adequate combinations.

15.
Clin Cancer Res ; 27(22): 6250-6264, 2021 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-34407971

RESUMEN

PURPOSE: Human papillomavirus (HPV) infection drives the development of some head and neck squamous cell carcinomas (HNSCC). This disease is rapidly increasing in incidence worldwide. Although these tumors are sensitive to treatment, approximately 10% of patients fail therapy. However, the mechanisms that underlie treatment failure remain unclear. EXPERIMENTAL DESIGN: We performed RNA sequencing (RNA-seq) on tissues from matched primary- (pHNSCC) and metachronous-recurrent cancers (rHNSCC) to identify transcriptional differences to gain mechanistic insight into the evolutionary adaptations of metachronous-recurrent tumors. We used HPV-related HNSCC cells lines to investigate the effect of (i) NRF2 overexpression on growth in vitro and in vivo, (ii) oxidative phosphorylation (OXPHOS) inhibition using IACS-010759 on NRF2-dependent cells, and (iii) combination of cisplatin and OXPHOS inhibition. RESULTS: The OXPHOS pathway is enriched in recurrent HPV-associated HNSCC and may contribute to treatment failure. NRF2-enriched HNSCC samples from The Cancer Genome Atlas (TCGA) with enrichment in OXPHOS, fatty-acid metabolism, Myc, Mtor, reactive oxygen species (ROS), and glycolytic signaling networks exhibited worse survival. HPV-positive HNSCC cells demonstrated sensitivity to the OXPHOS inhibitor, in a NRF2-dependent manner. Further, using murine xenograft models, we identified NRF2 as a driver of tumor growth. Mechanistically, NRF2 drives ROS and mitochondrial respiration, and NRF2 is a critical regulator of redox homeostasis that can be crippled by disruption of OXPHOS. NRF2 also mediated cisplatin sensitivity in endogenously overexpressing primary HPV-related HNSCC cells. CONCLUSIONS: These results unveil a paradigm-shifting translational target harnessing NRF2-mediated metabolic reprogramming in HPV-related HNSCC.


Asunto(s)
Alphapapillomavirus , Neoplasias de Cabeza y Cuello , Infecciones por Papillomavirus , Animales , Neoplasias de Cabeza y Cuello/genética , Humanos , Ratones , Recurrencia Local de Neoplasia/genética , Fosforilación Oxidativa , Papillomaviridae/genética , Infecciones por Papillomavirus/complicaciones , Infecciones por Papillomavirus/genética
16.
Health Policy Plan ; 36(5): 740-753, 2021 Jun 03.
Artículo en Inglés | MEDLINE | ID: mdl-33848340

RESUMEN

Costa Rica is a bright spot of primary healthcare (PHC) performance, providing first-contact accessibility and continuous, comprehensive, coordinated, and patient-centered care to its citizens. Previous research hypothesized that strong data collection and use for quality improvement are central to Costa Rica's success. Using qualitative data from 40 interviews with stakeholders across the Costa Rican healthcare system, this paper maps the various data streams at the PHC level and delineates how these data are used to make decisions around insuring and improving the quality of PHC delivery. We describe four main types of PHC data: individual patient data, population health data, national healthcare delivery data, and local supplementary healthcare delivery data. In particular, we find that the Healthcare Delivery Performance Index-a ranking of the nation's 106 Health Areas using 15 quality indicators-is utilized by Health Area Directors to create quality improvement initiatives, ranging from education and coaching to optimization of care delivery and coordination. By ranking Health Areas, the Index harnesses providers' intrinsic motivation to stimulate improvement without financial incentives. We detail how a strong culture of valuing data as a tool for improving population health and robust training for personnel have enabled effective data collection and use. However, we also find that the country's complex data systems create unnecessary duplication and can inhibit efficient data use. Costa Rica's experience with data collection, analysis, and use for quality improvement hold important lessons for PHC in other public sector systems.


Asunto(s)
Atención Primaria de Salud , Mejoramiento de la Calidad , Costa Rica , Recolección de Datos , Atención a la Salud , Humanos
17.
Mol Cancer ; 9: 143, 2010 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-20537188

RESUMEN

BACKGROUND: Lymphotropism in oral squamous cell carcinoma (OSCC) is one of the most important prognostic factors of 5-year survival. In an effort to identify genes that may be responsible for the initiation of OSCC lymphotropism, we examined DNA copy number gains and losses and corresponding gene expression changes from tumor cells in metastatic lymph nodes of patients with OSCC. RESULTS: We performed integrative analysis of DNA copy number alterations (CNA) and corresponding mRNA expression from OSCC cells isolated from metastatic lymph nodes of 20 patients using Affymetrix 250 K Nsp I SNP and U133 Plus 2.0 arrays, respectively. Overall, genome CNA accounted for expression changes in 31% of the transcripts studied. Genome region 11q13.2-11q13.3 shows the highest correlation between DNA CNA and expression. With a false discovery rate < 1%, 530 transcripts (461 genes) demonstrated a correlation between CNA and expression. Among these, we found two subsets that were significantly associated with OSCC (n = 122) when compared to controls, and with survival (n = 27), as tested using an independent dataset with genome-wide expression profiles for 148 primary OSCC and 45 normal oral mucosa. We fit Cox models to calculate a principal component analysis-derived risk-score for these two gene sets ('122-' or '27-transcript PC'). The models combining the 122- or 27-transcript PC with stage outperformed the model using stage alone in terms of the Area Under the Curve (AUC = 0.82 or 0.86 vs. 0.72, with p = 0.044 or 0.011, respectively). CONCLUSIONS: Genes exhibiting CNA-correlated expression may have biological impact on carcinogenesis and cancer progression in OSCC. Determination of copy number-associated transcripts associated with clinical outcomes in tumor cells with an aggressive phenotype (i.e., cells metastasized to the lymph nodes) can help prioritize candidate transcripts from high-throughput data for further studies.


Asunto(s)
Carcinoma de Células Escamosas/genética , Dosificación de Gen , Perfilación de la Expresión Génica , Neoplasias de la Boca/genética , Adulto , Anciano , Anciano de 80 o más Años , Área Bajo la Curva , Carcinoma de Células Escamosas/mortalidad , Carcinoma de Células Escamosas/patología , Femenino , Expresión Génica , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Neoplasias de la Boca/mortalidad , Neoplasias de la Boca/patología , Polimorfismo de Nucleótido Simple , Análisis de Componente Principal , Modelos de Riesgos Proporcionales , ARN Mensajero , Curva ROC , Adulto Joven
18.
Clin Cancer Res ; 15(4): 1353-61, 2009 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-19228736

RESUMEN

PURPOSE: To determine if gene expression signature of invasive oral squamous cell carcinoma (OSCC) can subclassify OSCC based on survival. EXPERIMENTAL DESIGN: We analyzed the expression of 131 genes in 119 OSCC, 35 normal, and 17 dysplastic mucosa to identify cluster-defined subgroups. Multivariate Cox regression was used to estimate the association between gene expression and survival. By stepwise Cox regression, the top predictive models of OSCC-specific survival were determined and compared by receiver operating characteristic analysis. RESULTS: The 3-year overall mean+/-SE survival for a cluster of 45 OSCC patients was 38.7+/-0.09% compared with 69.1+/-0.08% for the remaining patients. Multivariate analysis adjusted for age, sex, and stage showed that the 45 OSCC patient cluster had worse overall and OSCC-specific survival (hazard ratio, 3.31; 95% confidence interval, 1.66-6.58 and hazard ratio, 5.43; 95% confidence interval, 2.32-12.73, respectively). Stepwise Cox regression on the 131 probe sets revealed that a model with a term for LAMC2 (laminin gamma2) gene expression best identified patients with worst OSCC-specific survival. We fit a Cox model with a term for a principal component analysis-derived risk score marker and two other models that combined stage with either LAMC2 or PCA. The area under the curve for models combining stage with either LAMC2 or PCA was 0.80 or 0.82, respectively, compared with 0.70 for stage alone (P=0.013 and 0.008, respectively). CONCLUSIONS: Gene expression and stage combined predict survival of OSCC patients better than stage alone.


Asunto(s)
Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/mortalidad , Perfilación de la Expresión Génica , Neoplasias de la Boca/genética , Neoplasias de la Boca/mortalidad , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma de Células Escamosas/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Análisis de Componente Principal , Modelos de Riesgos Proporcionales , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa
19.
Biochem Mol Biol Educ ; 48(3): 247-252, 2020 05.
Artículo en Inglés | MEDLINE | ID: mdl-31899583

RESUMEN

The use of the thermodynamic formalism in the investigation of biochemical reactions constitutes one of the key analysis in bioenergetics, and the first step in such analysis is the selection of the adequate reference state. For biochemistry majors, thermodynamic analysis based on the chemical reference state is used in Physical Chemistry courses, while the biological and biochemical reference states are used in Biochemistry courses. As these definitions are introduced in different courses, it is difficult that students can understand the need to select a reference state as a first step in the energy analysis of a system. The lack of suitable examples in textbooks to illustrate the importance of the adequate selection of the reference state in a thermodynamic analysis, promoted the present analysis of the energetic role of pyrophosphate (PPi) in comparison with adenosine-triphosphate in different ambient conditions, namely, the early PPi world (better described by the chemical reference state), the enclosed systems like the cells (better described by the biological reference state), and the actual thioester world (better described by the biochemical reference state). This example not only provides a new interesting point of view on the evolution of two biochemical fuels but also represents a biochemical example in which the use of different reference states can illustrate a single process from different points of views.


Asunto(s)
Adenosina Trifosfato/metabolismo , Bioquímica/educación , Química Física/educación , Difosfatos/metabolismo , Animales , Bioquímica/normas , Química Física/normas , Metabolismo Energético , Humanos , Hidrólisis , Valores de Referencia , Estudiantes , Termodinámica , Uruguay
20.
BMJ Glob Health ; 5(8)2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32843571

RESUMEN

As the world strives to achieve universal health coverage by 2030, countries must build robust healthcare systems founded on strong primary healthcare (PHC). In order to strengthen PHC, country governments need actionable guidance about how to implement health reform. Costa Rica is an example of a country that has taken concrete steps towards successfully improving PHC over the last two decades. In the 1990s, Costa Rica implemented three key reforms: governance restructuring, geographic empanelment, and multidisciplinary teams. To understand how Costa Rica implemented these reforms, we conducted a process evaluation based on a validated implementation science framework. We interviewed 39 key informants from across Costa Rica's healthcare system in order to understand how these reforms were implemented. Using the Exploration Preparation Implementation Sustainment (EPIS) framework, we coded the results to identify Costa Rica's key implementation strategies and explore underlying reasons for Costa Rica's success as well as ongoing challenges. We found that Costa Rica implemented PHC reforms through strong leadership, a compelling vision and deliberate implementation strategies such as building on existing knowledge, resources and infrastructure; bringing together key stakeholders and engaging deeply with communities. These reforms have led to dramatic improvements in health outcomes in the past 25 years. Our in-depth analysis of Costa Rica's specific implementation strategies offers tangible lessons and examples for other countries as they navigate the important but difficult work of strengthening PHC.


Asunto(s)
Reforma de la Atención de Salud , Cobertura Universal del Seguro de Salud , Costa Rica , Atención a la Salud , Humanos
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA