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1.
Heliyon ; 10(7): e29311, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38633649

RESUMEN

The Venturi flow meter offers a range of measurement options for liquids, gas, steam, and slurries in piped systems. The main criteria for assessing Venturi performance include permanent pressure loss, discharge coefficient, relative pressure loss coefficient, and measurement accuracy. However, the extended length of Venturis, relative to other flow rate measuring instruments, can present limitations in some applications. Furthermore, the manufacturing of shorter Venturis requires less material and energy. This study addresses the challenge by developing shorter Venturi meters that adhere to established performance standards. Previous studies show that cone angles, the ratio of throat diameter to inlet diameter (ß-ratio), and the throat length impact the performance of a Venturi. The scope of this research considers single-phase, incompressible and isothermal flows. The investigation focuses on the effect of cone angles for flows with Reynolds numbers ranging from 5000 to 10,000,000. Two axisymmetric Venturis, with a ß-ratio of 0.7, were designed and evaluated against an ISO-5167 classical Venturi with the same ß-ratio. Despite the ISO-5167 Venturi outperforming the others across the key criteria, a Venturi designed with a 40-degree convergent cone angle and a 10-degree divergent cone angle was 24.9 % shorter than the classical design and demonstrated similar performance to the ISO-5167 Venturi across Reynolds numbers from 100,000 to 10,000,000.

2.
Cancers (Basel) ; 12(7)2020 Jul 17.
Artículo en Inglés | MEDLINE | ID: mdl-32708981

RESUMEN

Immunotherapy, such as anti-PD1, has improved the survival of patients with metastatic melanoma. However, predicting which patients will respond to immunotherapy remains a significant knowledge gap. In this study we analyzed pre-immunotherapy treated tumors from 52 patients with metastatic melanoma and monitored their response based on RECIST 1.1 criteria. The responders group contained 21 patients that had a complete or partial response, while the 31 non-responders had stable or progressive disease. Whole exome sequencing (WES) was used to identify biomarkers of anti-PD1 response from somatic mutations between the two groups. Variants in codons G34 and G41 in NFKBIE, a negative regulator of NFkB, were found exclusively in the responders. Mutations in NKBIE-related genes were also enriched in the responder group compared to the non-responders. Patients that harbored NFKBIE-related gene mutations also had a higher mutational burden, decreased tumor volume with treatment, and increased progression-free survival. RNA sequencing on a subset of tumor samples identified that CD83 was highly expressed in our responder group. Additionally, Gene Set Enrichment Analysis showed that the TNFalpha signaling via NFkB pathway was one of the top pathways with differential expression in responders vs. non-responders. In vitro NFkB activity assays indicated that the G34E variant caused loss-of-function of NFKBIE, and resulted in activation of NFkB signaling. Flow cytometry assays indicated that G34E variant was associated with upregulation of CD83 in human melanoma cell lines. These results suggest that NFkB activation and signaling in tumor cells contributes to a favorable anti-PD1 treatment response, and clinical screening to include aberrations in NFkB-related genes should be considered.

3.
Dermatol Online J ; 24(4)2018 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-29905998

RESUMEN

BACKGROUND: Although previous studies identify gender differences in melanoma, limited research on the phenomenon exists. METHODS: In this retrospective chart review, 1,156 adults diagnosed with melanoma, between 2006-2016, at the University of Colorado were included. Breslow depth, mitotic rate, ulceration status, and location were extracted from charts between March and August 2016. Cochran-Armitage trend tests and cumulative logistic regression were used to examine the association between gender and Breslow depth, univariately and after adjusting for potential confounders. RESULTS: In univariate analysis, males were significantly more likely to present with lesions with higher Breslow depths (p for trend=0.005). In models adjusted for age, melanoma subtype, and location, males were marginally more likely to present with lesions with higher Breslow depths (cumulative OR: 1.261, 95% CI: 0.988-1.611, p=0.060). Males were also marginally more likely to present with lesions with higher mitotic rates, after further adjustments for all other prognostic factors (cumulative OR: 1.244, 95% CI: 0.979-1.580, p=0.074). LIMITATIONS: This was a retrospective single-institution study. CONCLUSION: Differences in mitotic rates among melanomas in males versus females, even after adjustments for all other prognostic factors, suggests that biological differences may contribute to the female prognosis advantage.


Asunto(s)
Neoplasias de Cabeza y Cuello/patología , Melanoma/secundario , Mitosis , Neoplasias Cutáneas/patología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Neoplasias de Cabeza y Cuello/complicaciones , Neoplasias de Cabeza y Cuello/fisiopatología , Humanos , Extremidad Inferior , Masculino , Melanoma/complicaciones , Melanoma/fisiopatología , Persona de Mediana Edad , Índice Mitótico , Pronóstico , Estudios Retrospectivos , Factores Sexuales , Neoplasias Cutáneas/complicaciones , Neoplasias Cutáneas/fisiopatología , Úlcera Cutánea/etiología , Extremidad Superior , Adulto Joven
4.
Mol Cancer Ther ; 17(1): 222-231, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-29054983

RESUMEN

Oncogenic ALK fusions occur in several types of cancer and can be effectively treated with ALK inhibitors; however, ALK fusions and treatment response have not been characterized in malignant melanomas. Recently, a novel isoform of ALK (ALKATI ) was reported in 11% of melanomas but the response of melanomas expressing ALKATI to ALK inhibition has not been well characterized. We analyzed 45 melanoma patient-derived xenograft models for ALK mRNA and protein expression. ALK expression was identified in 11 of 45 (24.4%) melanomas. Ten melanomas express wild-type (wt) ALK and/or ALKATI and one mucosal melanoma expresses multiple novel EML4-ALK fusion variants. Melanoma cells expressing different ALK variants were tested for response to ALK inhibitors. Whereas the melanoma expressing EML4-ALK were sensitive to ALK inhibitors in vitro and in vivo, the melanomas expressing wt ALK or ALKATI were not sensitive to ALK inhibitors. In addition, a patient with mucosal melanoma expressing ALKATI was treated with an ALK/ROS1/TRK inhibitor (entrectinib) on a phase I trial but did not respond. Our results demonstrate ALK fusions occur in malignant melanomas and respond to targeted therapy, whereas melanomas expressing ALKATI do not respond to ALK inhibitors. Targeting ALK fusions is an effective therapeutic option for a subset of melanoma patients, but additional clinical studies are needed to determine the efficacy of targeted therapies in melanomas expressing wt ALK or ALKATIMol Cancer Ther; 17(1); 222-31. ©2017 AACR.


Asunto(s)
Melanoma/genética , Proteínas de Fusión Oncogénica/genética , Proteínas de Fusión Oncogénica/metabolismo , Animales , Femenino , Humanos , Melanoma/patología , Ratones , Ratones Desnudos , Persona de Mediana Edad , Isoformas de Proteínas , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Melanoma Res ; 27(3): 189-199, 2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28296713

RESUMEN

Mucosal melanomas are a rare subtype of melanoma, arising in mucosal tissues, which have a very poor prognosis due to the lack of effective targeted therapies. This study aimed to better understand the molecular landscape of these cancers and find potential new therapeutic targets. Whole-exome sequencing was performed on mucosal melanomas from 19 patients and 135 sun-exposed cutaneous melanomas, with matched peripheral blood samples when available. Mutational profiles were compared between mucosal subgroups and sun-exposed cutaneous melanomas. Comparisons of molecular profiles identified 161 genes enriched in mucosal melanoma (P<0.05). KIT and NF1 were frequently comutated (32%) in the mucosal subgroup, with a significantly higher incidence than that in cutaneous melanoma (4%). Recurrent SF3B1 R625H/S/C mutations were identified and validated in 7 of 19 (37%) mucosal melanoma patients. Mutations in the spliceosome pathway were found to be enriched in mucosal melanomas when compared with cutaneous melanomas. Alternative splicing in four genes were observed in SF3B1-mutant samples compared with the wild-type samples. This study identified potential new therapeutic targets for mucosal melanoma, including comutation of NF1 and KIT, and recurrent R625 mutations in SF3B1. This is the first report of SF3B1 R625 mutations in vulvovaginal mucosal melanoma, with the largest whole-exome sequencing project of mucosal melanomas to date. The results here also indicated that the mutations in SF3B1 lead to alternative splicing in multiple genes. These findings expand our knowledge of this rare disease.


Asunto(s)
Biomarcadores de Tumor/genética , Exoma/genética , Melanoma/genética , Membrana Mucosa/patología , Mutación , Neurofibromina 1/genética , Fosfoproteínas/genética , Proteínas Proto-Oncogénicas c-kit/genética , Factores de Empalme de ARN/genética , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Femenino , Estudios de Seguimiento , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad , Membrana Mucosa/metabolismo , Pronóstico
6.
Dermatol Online J ; 23(11)2017 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-29447632

RESUMEN

INTRODUCTION: Numerous studies report a correlation between distance to diagnostic provider in an academic medical center and poorer prognosis ofdisease. Limited research on this topic exists with respect to melanoma. METHODS: This was a retrospective chart review of 1,463 adults (≥18 years) initially diagnosed with melanoma between 2006-2016. Associations between distance traveled and Breslow depth and presence of metastatic disease were assessed via cumulative and binary logistic regression models, adjusting for patient and tumor characteristics. RESULTS: Subjects traveling ≥50 miles had 58% greater odds of having an increased Breslow depth than those traveling less than that distance (OR: 1.58; 95% CI: 1.24-2.01; p<0.0001), and had four times the odds of presenting with metastatic disease (OR: 4.04; 95% CI: 3.00-5.46; p<0.0001). DISCUSSION: We highlight the correlation between increased distance to our academic medical center with greater Breslow depths and the presence ofmetastatic disease at presentation. CONCLUSION: Future studies assessing other factors and regional differences that limit access to diagnosis might help improve screening efforts to prevent poorer prognosis for patients in these areas.


Asunto(s)
Centros Médicos Académicos , Melanoma , Neoplasias Cutáneas , Viaje , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Modelos Logísticos , Masculino , Melanoma/patología , Persona de Mediana Edad , Pronóstico , Estudios Retrospectivos , Factores de Riesgo , Neoplasias Cutáneas/patología
7.
Pigment Cell Melanoma Res ; 30(1): 53-62, 2017 01.
Artículo en Inglés | MEDLINE | ID: mdl-27864876

RESUMEN

Genomic rearrangements resulting in activating kinase fusions have been increasingly described in a number of cancers including malignant melanoma, but their frequency in specific melanoma subtypes has not been reported. We used break-apart fluorescence in situ hybridization (FISH) to identify genomic rearrangements in tissues from 59 patients with various types of malignant melanoma including acral lentiginous, mucosal, superficial spreading, and nodular. We identified four genomic rearrangements involving the genes BRAF, RET, and ROS1. Of these, three were confirmed by Immunohistochemistry (IHC) or sequencing and one was found to be an ARMC10-BRAF fusion that has not been previously reported in melanoma. These fusions occurred in different subtypes of melanoma but all in tumors lacking known driver mutations. Our data suggest gene fusions are more common than previously thought and should be further explored particularly in melanomas lacking known driver mutations.


Asunto(s)
Proteínas del Dominio Armadillo/genética , Melanoma/clasificación , Melanoma/genética , Proteínas de Fusión Oncogénica/genética , Proteínas Tirosina Quinasas/genética , Proteínas Proto-Oncogénicas B-raf/genética , Proteínas Proto-Oncogénicas c-ret/genética , Proteínas Proto-Oncogénicas/genética , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Reordenamiento Génico , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Melanoma/patología , Persona de Mediana Edad
8.
Oncologist ; 20(10): 1189-98, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26306903

RESUMEN

The WNT signaling cascade is integral in numerous biological processes including embryonic development, cell cycle regulation, inflammation, and cancer. Hyperactivation of WNT signaling secondary to alterations to varying nodes of the pathway have been identified in multiple tumor types. These alterations converge into increased tumorigenicity, sustained proliferation, and enhanced metastatic potential. This review seeks to evaluate the evidence supporting the WNT pathway in cancer, the therapeutic strategies in modulating this pathway, and potential challenges in drug development.


Asunto(s)
Antineoplásicos/farmacología , Terapia Molecular Dirigida/métodos , Neoplasias/tratamiento farmacológico , Vía de Señalización Wnt/efectos de los fármacos , Animales , Antineoplásicos/uso terapéutico , Ensayos Clínicos como Asunto , Humanos , Péptidos y Proteínas de Señalización Intercelular/inmunología , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Neoplasias/metabolismo , beta Catenina/genética , beta Catenina/metabolismo
9.
Biofabrication ; 7(2): 025003, 2015 Apr 14.
Artículo en Inglés | MEDLINE | ID: mdl-25869447

RESUMEN

The use of materials to impose tissue-like architecture at cell resolution will be important if engineered functional replacements for damaged cardiovascular, pulmonary, renal or digestive tissues are to be authentically engineered. Here, we demonstrate a coordinated system for the fabrication and subsequent culture of tubular tissues composed of multiple layers, cell-types and materials with physiological dimensions and defined architectures at cell resolution. We developed an automated tube fabricator that rolls 2D-matrices into 3D-tubular constructs directly from cells, hydrogels and scaffold biomaterials. Coordinated use of surface modification strategies allows 2D cell sheets and cell/biomaterial composites (i.e. hydrogels or electrospun scaffolds) to be fabricated which may be transferred into a perfusion bioreactor in a rapid and standardized procedure. To exemplify our strategy we fabricated structures resembling human mammary artery and gut; these can be imaged in situ and real-time electrical resistance measurements performed of the vessel walls, allowing non-invasive assessment of viability and functionality. Our system allows patterning at cellular resolution with variable tissue thickness, length, luminal diameter, and constituent biomaterial. This inherent flexibility will allow the recapitulation of the complex hierarchical biological architectures and generate functionality found natively in vivo.


Asunto(s)
Andamios del Tejido , Células 3T3 , Animales , Automatización , Órganos Bioartificiales , Materiales Biomiméticos/química , Reactores Biológicos , Técnicas de Cultivo de Célula , Células Cultivadas , Células Endoteliales de la Vena Umbilical Humana , Humanos , Hidrogeles/química , Ratones , Polímeros/química , Ingeniería de Tejidos
10.
J Oncol ; 2011: 201593, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-22203844

RESUMEN

Oxaliplatin use in palliative and adjuvant treatment of colon cancer is frequently limited by cumulative neurotoxicity, leading to reduced quality of life and decreased dose. The mechanism of this neurotoxicity is unclear, but may relate to neuronal voltage-gated sodium channels involving calcium chelation by a metabolite of the drug. Various preventative measures have been tested to reduce the incidence of neurotoxicity, including calcium and magnesium infusions, dose interruption of the drug, and prophylactic neuromodulatory agents. Despite the promising efficacy of these measures, they are not universally accepted. Less is known about the best way to treat established neurotoxicity, which is permanent in some patients, although venlafaxine has shown promise in small clinical trials. This paper analyzes the extent, cause and risk factors for neuropathy, and the potential preventative and therapeutic treatments for oxaliplatin-induced neuropathy.

12.
Vaccine ; 20(7-8): 1004-18, 2002 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-11803060

RESUMEN

ChimeriVax is a live, attenuated recombinant virus constructed from yellow fever (YF) 17D in which the envelope protein genes of YF 17D are replaced with the corresponding genes of another flavivirus. A ChimeriVax vaccine was developed against Japanese encephalitis (JE). A randomized, double-blind, outpatient study was conducted to compare the safety and immunogenicity of ChimeriVax-JE and YF 17D. Six YF immune and six non-immune adults were randomized to receive a single SC inoculation of ChimeriVax-JE (5log(10)PFU), ChimeriVax-JE (4log(10)PFU) or YF-VAX((R)) (5log(10)PFU). Mild, transient injection site reactions and flu-like symptoms were noted in all treatment groups, with no significant difference between the groups. Nearly all subjects inoculated with ChimeriVax-JE at both dose levels developed a transient, low-level viremia which was similar in magnitude and duration to that following YF-VAX). Neutralizing antibody seroconversion rates to ChimeriVax-JE was 100% in the high and low dose groups in both naïve and YF immune subjects; seroconversion to wild-type JE strains was similar or lower than to the homologous (vaccine) virus. Mean neutralizing antibody responses were higher in the ChimeriVax-JE high dose groups (naïve subjects LNI 1.55, PRNT(50) 254; YF immune subjects LNI 2.23, PRNT(50) 327) than in the low dose groups (naïve subjects 1.38, PRNT(50) 128; YF immune subjects LNI 1.62, PRNT(50) 270). JE antibody levels were higher in YF immune than in naïve subjects, dispelling concerns about anti-vector immunity. The safety and immunogenicity profile of ChimeriVax-JE vaccine appears to be similar to that of YF 17D. The new vaccine holds promise for prevention of JE in travelers and residents of endemic countries. The ChimeriVax technology platform is being exploited for development of new vaccines against dengue and West Nile.


Asunto(s)
Infecciones por Flavivirus/prevención & control , Vacunas contra la Encefalitis Japonesa/inmunología , Proteínas Recombinantes de Fusión/inmunología , Vacunas Sintéticas/inmunología , Vacuna contra la Fiebre Amarilla/inmunología , Adulto , Alanina Transaminasa/sangre , Anticuerpos Antivirales/sangre , Método Doble Ciego , Femenino , Humanos , Inmunoglobulina M/sangre , Recuento de Leucocitos , Masculino , Vacunas Atenuadas/inmunología , Vacunas Sintéticas/efectos adversos , Viremia/prevención & control
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