Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
1.
Clin Cancer Res ; 25(14): 4363-4374, 2019 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-30914433

RESUMEN

PURPOSE: Breast cancers with BRCA1/2 alterations have a relatively high mutational load, suggesting that immune checkpoint blockade may be a potential treatment option. However, the degree of immune cell infiltration varies widely, and molecular features contributing to this variability remain unknown. EXPERIMENTAL DESIGN: We hypothesized that genomic signatures might predict immunogenicity in BRCA1/2 breast cancers. Using The Cancer Genome Atlas (TCGA) genomic data, we compared breast cancers with (89) and without (770) either germline or somatic BRCA1/2 alterations. We also studied 35 breast cancers with germline BRCA1/2 mutations from Penn using WES and IHC. RESULTS: We found that homologous recombination deficiency (HRD) scores were negatively associated with expression-based immune indices [cytolytic index (P = 0.04), immune ESTIMATE (P = 0.002), type II IFN signaling (P = 0.002)] despite being associated with a higher mutational/neoantigen burden, in BRCA1/2 mutant breast cancers. Further, absence of allele-specific loss of heterozygosity (LOH negative; P = 0.01) or subclonality (P = 0.003) of germline and somatic BRCA1/2 mutations, respectively, predicted for heightened cytolytic activity. Gene set analysis found that multiple innate and adaptive immune pathways that converge on NF-κB may contribute to this heightened immunogenicity. IHC of Penn breast cancers demonstrated increased CD45+ (P = 0.039) and CD8+ infiltrates (P = 0.037) and increased PDL1 expression (P = 0.012) in HRD-low or LOH-negative cancers. Triple-negative cancers with low HRD had far greater CD8+ T cells (P = 0.0011) and Perforin 1 expression (P = 0.014) compared with hormone receptor-positive HRD-high cancers. CONCLUSIONS: HRD scores and hormone receptor subtype are predictive of immunogenicity in BRCA1/2 breast cancers and may inform the design of optimal immune therapeutic strategies.


Asunto(s)
Antineoplásicos Inmunológicos/uso terapéutico , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias de la Mama/genética , Neoplasias de la Mama/inmunología , Linfocitos T CD8-positivos/inmunología , Recombinación Homóloga , Antígeno B7-H1/antagonistas & inhibidores , Antígeno B7-H1/inmunología , Proteína BRCA1/metabolismo , Proteína BRCA2/metabolismo , Biomarcadores de Tumor/genética , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/patología , Femenino , Genómica/métodos , Humanos
2.
Clin Chim Acta ; 384(1-2): 105-12, 2007 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17632094

RESUMEN

BACKGROUND: Acrolein is a very reactive aldehyde present in cigarette smoke and endogenously generated by pathways such as lipid peroxidation and threonine metabolism by phagocytes. Acrolein has been shown to affect uptake of cholesterol by HDL. We hypothesized that acrolein could also have deleterious effects on paraoxonase 1 (PON-1) activity. We also determined whether free serum acrolein levels are higher in renal failure, and assessed whether they decrease after hemodialysis (HD) and whether this change correlates with increases in PON-1 activity. METHODS: We incubated human HDL with 0-10 mmol/l acrolein for 2 h and measured PON-1 activity and structural changes. Acrolein was also measured in 40 end stage renal disease (ESRD) patients (before and after a hemodialysis session), and 40 control subjects. RESULTS: We found that acrolein inhibits PON-1 activity in HDL in a time and concentration dependent fashion. Inhibition occurred at 40% at 0.5 mmol/l and was cancelled by cysteine but not by aminoguanidine or carnosine. We confirm that free serum acrolein levels are higher in chronic renal failure patients and demonstrate that they are partially removed by HD. Decrease in acrolein levels after dialysis correlate with increases in PON-1 activity (r=0.32, p 0.01). CONCLUSION: Acrolein inactivates paraoxonase 1 in HDL, a process that is inhibited by N-acetylcysteine. We confirm that acrolein levels are higher in ESRD and show for the first time, data supporting that acrolein is partially removed by hemodialysis. Decrease in acrolein levels after dialysis correlates with increase in PON-1 activity. This could offer new insights to explain low PON-1 activities in smokers and renal failure subjects as well as pointing at thiol-conserving reducing compounds such as N-acetylcysteine, as putative therapeutic palliatives.


Asunto(s)
Acroleína/sangre , Arildialquilfosfatasa/sangre , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/terapia , Diálisis Renal , Acetilcisteína/uso terapéutico , Acroleína/antagonistas & inhibidores , Acroleína/toxicidad , Anciano , Arildialquilfosfatasa/antagonistas & inhibidores , Cisteína/química , Cisteína/farmacología , Femenino , Humanos , Fallo Renal Crónico/tratamiento farmacológico , Lipoproteínas HDL/química , Lipoproteínas HDL/metabolismo , Masculino , Persona de Mediana Edad , Resultado del Tratamiento
3.
J Spec Oper Med ; 16(2): 5-8, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27450595

RESUMEN

Balanced component therapy (BCT) remains the mainstay in trauma resuscitation of the critically battle injured. In austere medical environments, access to packed red blood cells, apheresis platelets, and fresh frozen plasma is often limited. Transfusion of warm, fresh whole blood (FWB) has been used to augment limited access to full BCT in these settings. The main limitation of FWB is that it is not readily available for transfusion on casualty arrival. This small case series evaluates the impact early, mechanism-of-injury (MOI)-based, preactivation of the walking blood bank has on time to transfusion. We report an average time of 18 minutes to FWB transfusion from patient arrival. Early activation of the walking blood bank based on prehospital MOI may further reduce the time to FWB transfusion.


Asunto(s)
Amputación Traumática/terapia , Bancos de Sangre , Transfusión Sanguínea , Servicios Médicos de Urgencia , Hemorragia/terapia , Personal Militar , Tiempo de Tratamiento , Adulto , Amputación Traumática/complicaciones , Hemorragia/etiología , Humanos , Masculino , Adulto Joven
4.
Fitoterapia ; 76(5): 419-27, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-15894431

RESUMEN

Glycation, the nonenzymatic adduct formation between sugar dicarbonyls and proteins, is one key molecular basis of diabetic complications due to hyperglycemia. Given the link between glycation and oxidation, we hypothesized that herbal extracts with a high concentration of antioxidant phenolics might possess significant in vitro antiglycation activities as well. The aim of the present study was to address the hypothesis that polyphenol-rich Ilex paraguariensis (IP) extracts are capable of inhibiting advanced glycation end-products (AGEs) formation and to compare the potency of these extracts with green tea and with the standard antiglycation agent aminoguanidine. When we studied the effects of IP extract on AGE fluorescence generated on bovine serum albumin (BSA) by glycation with methylglyoxal, a dose-dependent effect that reaches 40% at 20 mul/ml of extract was demonstrated. Green tea did not display any significant effect. IP polyphenols are about 2- to 2.5-fold higher in our preparations compared with green tea. The effect of IP, therefore, may be due not only to the higher concentrations but to the different composition in phenolics of the two botanical preparations as well. To better discriminate between an antioxidant or a carbonyl quenching mechanism of action, we explored tryptophan fluorescence and cross-linking by sodium dodecyl sulfate polyacrylamide gel (SDS-PAGE) electrophoresis. The conformational changes induced by glycation and substitution of positive charges in arginine and/or lysine produce a decrease in tryptophan fluorescence. We show that incubation of BSA with methylglyoxal produces dramatic changes in tryptophan fluorescence that are prevented by aminoguanidine. This also prevents the downstream effect of AGE formation. Neither green tea nor IP extracts displayed any significant effect which rules out any significant participation as inhibitors in the first phase of the glycation cascade. The results from the SDS-PAGE serve to confirm the above-mentioned data. The effect is therefore due mainly to an inhibition of the second phase of the glycation reactions, namely the free-radical mediated conversion of the Amadori products to AGE. Taken together our results demonstrate a significant, dose-dependent effect of water extracts of I. paraguensis on AGE adducts formation on a protein model in vitro, whereas green tea displays no significant effect. The inhibition of AGE formation was comparable to that obtained by using millimolar concentrations of the standard antiglycation agent aminoguanidine.


Asunto(s)
Antioxidantes/farmacología , Productos Finales de Glicación Avanzada/química , Ilex paraguariensis , Fitoterapia , Extractos Vegetales/farmacología , , Antioxidantes/administración & dosificación , Antioxidantes/uso terapéutico , Relación Dosis-Respuesta a Droga , Productos Finales de Glicación Avanzada/antagonistas & inhibidores , Guanidinas , Humanos , Extractos Vegetales/administración & dosificación , Extractos Vegetales/uso terapéutico , Hojas de la Planta , Albúmina Sérica Bovina/química
5.
J Trauma Acute Care Surg ; 79(5): 790-6, 2015 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-26496103

RESUMEN

BACKGROUND: In Afghanistan, care of the acutely injured trauma patient commonly occurred in facilities with limited blood banking capabilities. Apheresis platelets were often not available. Component therapy consisted of 1:1 packed red blood cells and fresh frozen plasma. Fresh, whole blood transfusion often augmented therapy in the severely injured patient. This study analyzed the safety of fresh, whole blood use in a resource-limited setting. METHODS: A retrospective analysis was performed on a prospectively collected data set of US battle injuries presenting to three US Marine Corps (USMC) expeditionary surgical care facilities in Helmand Province, Afghanistan, between January 2010 and July 2012. Included in the review were patients with Injury Severity Scores (ISSs) of 15 or higher receiving blood transfusions. Univariate analyses were performed, followed by multivariable logistic regression to describe the relationship between the treatment group and posttreatment complications such as trauma-induced coagulopathy, infection, mortality, venous thromboembolism, and transfusion reaction. Propensity scores were calculated and included in multivariable models to adjust for potential bias in treatment selection. RESULTS: A total of 61 patients were identified; all were male marines with a mean (SD) age of 23.5 (3.6) years. The group receiving fresh, whole blood was noted to have higher ISSs and lower blood pressure, pH, and base deficits on arrival. Traumatic coagulopathy was significantly less common in the group receiving fresh, whole blood (odds ratio, 0.01; 95% confidence interval, 0.00-0.18). Multivariable models found no other significant differences between the treatment groups. CONCLUSION: The early use of fresh, whole blood in a resource-limited setting seems to confer a benefit in reducing traumatic coagulopathy. This study's small sample size precludes further statement on the overall safety of fresh, whole blood use. LEVEL OF EVIDENCE: Therapy study, level IV.


Asunto(s)
Transfusión Sanguínea/métodos , Causas de Muerte , Procedimientos Quirúrgicos Operativos/métodos , Heridas Relacionadas con la Guerra/terapia , Guerra , Adulto , Afganistán , Análisis de Varianza , Estudios de Cohortes , Bases de Datos Factuales , Estudios de Seguimiento , Humanos , Puntaje de Gravedad del Traumatismo , Modelos Logísticos , Masculino , Personal Militar , Análisis Multivariante , Seguridad del Paciente , Estudios Retrospectivos , Medición de Riesgo , Procedimientos Quirúrgicos Operativos/mortalidad , Tasa de Supervivencia , Reacción a la Transfusión , Resultado del Tratamiento , Heridas Relacionadas con la Guerra/diagnóstico , Heridas Relacionadas con la Guerra/mortalidad , Heridas Relacionadas con la Guerra/cirugía , Adulto Joven
6.
Mil Med ; 178(3): e376-9, 2013 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-23707129

RESUMEN

The role of bedside ultrasound by physicians with advanced ultrasound training, such as emergency medicine providers, has been clearly established in the austere setting of combat medicine. This highly mobile, noninvasive, and versatile imaging modality has a role in evaluating battle- and nonbattle-related presentations. This case report describes a U.S. Marine reporting to an austere medical facility with the chief complaint of abdominal pain. An ultrasound of the patient's urinary tract revealed abnormalities that suggested right bladder wall thickening and an echo dense layer of sediment as the potential source of his discomfort. These findings supported patient transfer to a higher echelon of care. Further diagnostic testing revealed Crohn's disease with an associated enterovesicular fistula.


Asunto(s)
Colon/diagnóstico por imagen , Enfermedad de Crohn/complicaciones , Fístula Intestinal/diagnóstico por imagen , Sistemas de Atención de Punto/estadística & datos numéricos , Vejiga Urinaria/diagnóstico por imagen , Fístula Urinaria/diagnóstico por imagen , Adulto , Colonoscopía , Enfermedad de Crohn/diagnóstico , Diagnóstico Diferencial , Humanos , Fístula Intestinal/etiología , Masculino , Tomografía Computarizada por Rayos X , Ultrasonografía , Fístula Urinaria/etiología
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA