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1.
Ind Eng Chem Res ; 63(1): 78-88, 2024 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-38223498

RESUMEN

The impact of solution stoichiometry on the nucleation and growth of BaSO4 was studied by measuring solution transmittance and subsequent fitting to a crystallization model. Our results show that a large excess of either Ba2+ or SO42- ions inhibits both the nucleation and growth of BaSO4. However, for a small excess of Ba2+, the growth is enhanced. The dependence of nucleation and growth rates on supersaturation and solution stoichiometry was captured by a semiempirical rate model. Hence, the solution stoichiometry is a highly relevant parameter while studying all aspects of BaSO4 crystallization, and it could be worthwhile to examine other minerals similarly.

2.
Ann Oncol ; 34(9): 783-795, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37302750

RESUMEN

BACKGROUND: The HER2DX genomic test predicts pathological complete response (pCR) and survival outcome in early-stage HER2-positive (HER2+) breast cancer. Here, we evaluated the association of HER2DX scores with (i) pCR according to hormone receptor status and various treatment regimens, and (ii) survival outcome according to pCR status. MATERIALS AND METHODS: Seven neoadjuvant cohorts with HER2DX and clinical individual patient data were evaluated (DAPHNe, GOM-HGUGM-2018-05, CALGB-40601, ISPY-2, BiOnHER, NEOHER and PAMELA). All patients were treated with neoadjuvant trastuzumab (n = 765) in combination with pertuzumab (n = 328), lapatinib (n = 187) or without a second anti-HER2 drug (n = 250). Event-free survival (EFS) and overall survival (OS) outcomes were available in a combined series of 268 patients (i.e. NEOHER and PAMELA) with a pCR (n = 118) and without a pCR (n = 150). Cox models were adjusted to evaluate whether HER2DX can identify patients with low or high risk beyond pCR status. RESULTS: HER2DX pCR score was significantly associated with pCR in all patients [odds ratio (OR) per 10-unit increase = 1.59, 95% confidence interval 1.43-1.77; area under the ROC curve = 0.75], with or without dual HER2 blockade. A statistically significant increase in pCR rate due to dual HER2 blockade over trastuzumab-only was observed in HER2DX pCR-high tumors treated with chemotherapy (OR = 2.36 (1.09-5.42). A statistically significant increase in pCR rate due to multi-agent chemotherapy over a single taxane was observed in HER2DX pCR-medium tumors treated with dual HER2 blockade (OR = 3.11, 1.54-6.49). The pCR rates in HER2DX pCR-low tumors were ≤30.0% regardless of treatment administered. After adjusting by pCR status, patients identified as HER2DX low-risk had better EFS (P < 0.001) and OS (P = 0.006) compared with patients with HER2DX high-risk. CONCLUSIONS: HER2DX pCR score and risk score might help identify ideal candidates to receive neoadjuvant dual HER2 blockade in combination with a single taxane in early-stage HER2+ breast cancer.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/genética , Neoplasias de la Mama/patología , Receptor ErbB-2/genética , Resultado del Tratamiento , Trastuzumab , Taxoides , Terapia Neoadyuvante/efectos adversos , Protocolos de Quimioterapia Combinada Antineoplásica/efectos adversos
3.
J Chem Phys ; 158(5): 054501, 2023 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-36754828

RESUMEN

Multiple-step nucleation pathways have been observed during mineral formation in both inorganic and biomineral systems. These pathways can involve precursor aqueous species, amorphous intermediates, or metastable phases. Despite the widespread occurrence of these processes, elucidating the precise nucleation steps and the transformation mechanisms between each step remains a challenging task. Using a suite of potentiometric, microscopic, and spectroscopic tools, we studied the nucleation pathway of SrSO4 as a function of the physico-chemical solution parameters. Our observations reveal that below a threshold supersaturation, nucleation is driven by bound species, akin to the prenucleation cluster model, which directly leads to the formation of the stable phase celestine, SrSO4. At higher supersaturations, this situation is altered, with nucleation dominated by the consumption of free ions. Importantly, this change in nucleation mechanism is coupled to the formation of a hemihydrate metastable phase, SrSO4 · 1/2H2O, which eventually transforms into celestine, adhering to Ostwald's rule of stages. This transformation is a solution-mediated process, also occurring in the presence of a fluid film and is controlled by the physico-chemical parameters of the surrounding environment. It proceeds through the dissolution of the metastable phase and the de novo crystallization of the final phase. Overall, our results reveal that ion association taking place during the prenucleation stage dictates whether the nucleation pathway goes through an intermediate phase or not. This also underlines that although Ostwald's rule of stages is a common process, it is not a prerequisite for mineral formation-even in systems where it can occur.

4.
Faraday Discuss ; 235(0): 95-108, 2022 Jul 14.
Artículo en Inglés | MEDLINE | ID: mdl-35389401

RESUMEN

In this work we link experimental results of SrSO4 precipitation with a nucleation model based on mesoscopic nucleation theory (MeNT) to stride towards a cohesive view of the nucleation process that integrates both classical and non-classical views. When SrCl2 and Na2SO4 are co-titrated at slow dosing rates, time-resolved turbidity, conductivity and ion-specific data reveal that the initial stage of the nucleation process is driven by neutral species, i.e. ion-pairs or larger, akin to the prenucleation cluster model. However, when co-titrations are conducted at higher rates, the onset of nucleation is dominated by the consumption of free ions, akin to the explanation provided by classical nucleation theory (CNT). The occurrence of both mechanisms for the same system is explained by a toy model that includes both the thermodynamics (consisting of a single energy barrier) and kinetics of cluster formation formally obtained from MeNT. This gives rise to an effective energy barrier exhibiting a local intermediate minimum, which does not originate from a minimum in the thermodynamic free energy. Rather, it is associated with an increased probability of observing a specific class (in terms of size/density) of precursor clusters due to their slower kinetics. At high supersaturations this minimum in the kinetics of cluster formation becomes less pronounced and the effective barrier is also significantly lowered. Consequently, the probability of observing an intermediate state is blurred and we recover a nucleation pathway more closely following the one envisaged by the classical model. Thus, our model is capable of capturing both single and multistep nucleation mechanisms observed experimentally considering only a single energy barrier.

5.
Rev Neurol ; 71(8): 292-297, 2020 Oct 16.
Artículo en Español | MEDLINE | ID: mdl-33034367

RESUMEN

INTRODUCTION: Idiopathic intracranial hypertension is an entity with an incidence of approximately 1.2: 100,000 inhabitants/year. It affects in a greater proportion obese women and women of childbearing age. Headache is the most characteristic symptom, followed by visual disturbances. In recent years, the diagnosis of dural sinus stenosis has increased in cases of intracranial hypertension resistant to conventional treatment. For this reason, the development of endovascular therapy as a therapeutic option in selected patients is booming. CASE REPORTS: We present three cases of intracranial hypertension secondary to dural sinus stenosis, diagnosed and treated in our hospital. Despite the establishment of adequate diuretic treatment and the performance of invasive procedures to bypass the cerebrospinal fluid, they persisted with neurological symptoms and visual deficits. After verifying that they fulfilled the requirements described in the literature, they underwent intracranial stenting, with satisfactory results in all of them, achieving the disappearance of the headache and recovery of visual acuity. CONCLUSION: Stenting of dural sinus stenosis as a cause of intracranial hypertension is an increasingly used technique, which has presented favorable results. Studies are necessary to know its long-term impact.


TITLE: Tratamiento endovascular de la estenosis de los senos venosos intracraneales en la hipertensión intracraneal: descripción de tres casos y discusión de la bibliografía.Introducción. La hipertensión intracraneal idiopática es una entidad con una incidencia anual aproximada de 1,2 por cada 100.000 habitantes. Afecta en mayor proporción a mujeres obesas y en edad fértil. La cefalea es el síntoma más característico, seguido de las alteraciones visuales. En los últimos años, se ha incrementado el diagnóstico de la estenosis de los senos durales en los casos de hipertensión intracraneal resistentes al tratamiento convencional. Por ello, se encuentra en auge el desarrollo de la terapia endovascular como opción terapéutica en pacientes seleccionados. Casos clínicos. Se presentan tres casos de hipertensión intracraneal secundaria a estenosis de los senos durales, diagnosticados y tratados en nuestro hospital. A pesar de la instauración del adecuado tratamiento diurético y de la realización de procedimientos invasivos de derivación del líquido cefalorraquídeo, persistían la clínica neurológica y el déficit visual. Tras comprobar que cumplían los requisitos descritos en la bibliografía, se sometieron a la implantación de stent intracraneal (stenting), con resultado satisfactorio en todos ellos, logrando la desaparición de la cefalea y la recuperación de la agudeza visual. Conclusión. El stenting de la estenosis de los senos durales como causa de hipertensión intracraneal es una técnica cada vez más utilizada que ha presentado resultados favorables. Es necesaria la realización de estudios para conocer su impacto a largo plazo.


Asunto(s)
Seudotumor Cerebral , Stents , Constricción Patológica , Femenino , Humanos , Seudotumor Cerebral/complicaciones , Seudotumor Cerebral/terapia , Trastornos de la Visión/etiología
6.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 37(2): 80-86, mar.-abr. 2018. tab, ilus, graf
Artículo en Español | IBECS | ID: ibc-171451

RESUMEN

Objetivo. El Standardized uptake value (SUV) y los parámetros volumétricos volumen metabólico tumoral (MTV) y glicolisis total de la lesión (TLG) de la 18F-FDG PET/TC son útiles para determinar el pronóstico preoperatorio y postratamiento del cáncer epitelial de ovario (CEO). El Ki67 es otro marcador pronóstico en el CEO asociado con la agresividad tumoral. El objetivo fue estudiar la asociación entre los parámetros de la 18F-FDG PET/TC y el Ki67 en el CEO pretratamiento para determinar si la PET/TC puede predecir la agresividad tumoral de forma no invasiva. Material y métodos. Se realizó una PET/TC a 18 pacientes con sospecha o recién diagnóstico de CEO. Se obtuvo el SUV máximo (SUVmax), SUV medio (SUVmean) y el MTV y la TLG corporal (wbMTV y wbTLG, respectivamente), con un dintel del 30%-40% del SUVmax. Se estimó el índice de Ki67 (medio y máximo) en muestras del tejido tumoral, y se correlacionó con los parámetros de la PET. Resultados. La edad media fue 57,0 años (desviación estándar 13,6 años). Se observó una moderada correlación entre el Ki67 medio y el SUVmax (r=0.392), SUVmean 30% (r=0.437) y SUVmean 40% (r=0.443), así como entre el Ki67 máximo y el SUVmax (r=0.360), SUVmean 30% (r=0.362) y SUVmean 40% (r=0.319). La correlación fue más débil, e inversamente negativa, entre el Ki67 medio y máximo y los parámetros volumétricos de la PET. No hubo diferencias estadísticamente significativas entre las correlaciones. Conclusiones. SUVmax y SUVmean se correlacionaron moderadamente con el Ki67 mientras que los parámetros volumétricos mostraron una correlación débil. SUVmax y SUVmean podrían utilizarse para predecir la agresividad tumoral en el CEO pretratamiento (AU)


Objective. Standardised uptake value (SUV) and volumetric parameters such as metabolic tumour volume (MTV) and total lesion glycolysis (TLG) from 18F-FDG PET/CT are useful criteria for disease prognosis in pre-operative and post-treatment epithelial ovarian cancer (EOC). Ki67 is another prognostic biomarker in EOC, associated with tumour aggressiveness. The aim of this study is to evaluate the association between 18F-FDG PET/CT measurements and Ki67 in pre-treatment EOC to determine if PET/CT parameters could non-invasively predict tumour aggressiveness. Material and methods. A pre-treatment PET/CT was performed on 18 patients with suspected or newly diagnosed EOC. Maximum SUV (SUVmax), mean SUV (SUVmean), whole-body MTV (wbMTV), and whole-body TLG (wbTLG) with a threshold of 30% and 40% of the SUVmax were obtained. Furthermore, Ki67 index (mean and hotspot) was estimated in tumour tissue specimens. Immunohistochemical findings were correlated with PET parameters. Results. The mean age was 57.0 years old (standard deviation 13.6 years). A moderate correlation was observed between mean Ki67 index and SUVmax (r=0.392), SUVmean 30% (r=0.437), and SUVmean 40% (r=0.443), and also between hotspot Ki67 index and SUVmax (r=0.360), SUVmean 30% (r=0.362) and SUVmean 40% (r=0.319). There was a weaker correlation, which was inversely negative, between mean and hotspot Ki67 and volumetric PET parameters. However, no statistical significant differences were found for any correlations. Conclusions. SUVmax and SUVmean were moderately correlated with Ki67 index, whereas volumetric PET parameters overall, showed a weaker correlation. Thus, SUVmax and SUVmean could be used to assess tumour aggressiveness in pre-treatment EOC (AU)


Asunto(s)
Humanos , Tomografía Computarizada por Tomografía de Emisión de Positrones/métodos , Fluorodesoxiglucosa F18/farmacocinética , Antígeno Ki-67/análisis , Neoplasias Ováricas/diagnóstico por imagen , Células Epiteliales/patología , Sensibilidad y Especificidad , Volumetría/métodos , Neoplasias Ováricas/metabolismo , Glucólisis/efectos de la radiación , Inmunohistoquímica/métodos
7.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28869177

RESUMEN

OBJECTIVE: Standardised uptake value (SUV) and volumetric parameters such as metabolic tumour volume (MTV) and total lesion glycolysis (TLG) from 18F-FDG PET/CT are useful criteria for disease prognosis in pre-operative and post-treatment epithelial ovarian cancer (EOC). Ki67 is another prognostic biomarker in EOC, associated with tumour aggressiveness. The aim of this study is to evaluate the association between 18F-FDG PET/CT measurements and Ki67 in pre-treatment EOC to determine if PET/CT parameters could non-invasively predict tumour aggressiveness. MATERIAL AND METHODS: A pre-treatment PET/CT was performed on 18 patients with suspected or newly diagnosed EOC. Maximum SUV (SUVmax), mean SUV (SUVmean), whole-body MTV (wbMTV), and whole-body TLG (wbTLG) with a threshold of 30% and 40% of the SUVmax were obtained. Furthermore, Ki67 index (mean and hotspot) was estimated in tumour tissue specimens. Immunohistochemical findings were correlated with PET parameters. RESULTS: The mean age was 57.0 years old (standard deviation 13.6 years). A moderate correlation was observed between mean Ki67 index and SUVmax (r=0.392), SUVmean 30% (r=0.437), and SUVmean 40% (r=0.443), and also between hotspot Ki67 index and SUVmax (r=0.360), SUVmean 30% (r=0.362) and SUVmean 40% (r=0.319). There was a weaker correlation, which was inversely negative, between mean and hotspot Ki67 and volumetric PET parameters. However, no statistical significant differences were found for any correlations. CONCLUSIONS: SUVmax and SUVmean were moderately correlated with Ki67 index, whereas volumetric PET parameters overall, showed a weaker correlation. Thus, SUVmax and SUVmean could be used to assess tumour aggressiveness in pre-treatment EOC.


Asunto(s)
Antígenos de Neoplasias/análisis , Carcinoma/diagnóstico por imagen , Radioisótopos de Flúor/farmacocinética , Fluorodesoxiglucosa F18/farmacocinética , Antígeno Ki-67/análisis , Neoplasias Glandulares y Epiteliales/diagnóstico por imagen , Neoplasias Ováricas/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Radiofármacos/farmacocinética , Adulto , Anciano , Carcinoma/metabolismo , Carcinoma Epitelial de Ovario , Simulación por Computador , Femenino , Glucólisis , Humanos , Interpretación de Imagen Asistida por Computador , Técnicas para Inmunoenzimas , Persona de Mediana Edad , Neoplasias Glandulares y Epiteliales/metabolismo , Neoplasias Ováricas/metabolismo , Estudios Prospectivos , Distribución Tisular , Carga Tumoral , Adulto Joven
8.
Phys Chem Chem Phys ; 19(26): 17009-17018, 2017 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-28636046

RESUMEN

The long-chain members of the lead(ii) alkanoate series or soaps, from octanoate to octadecanoate, have been thoroughly characterized by means of XRD, PDF analysis, DSC, FTIR, ssNMR and other techniques, in all their phases and mesophases. The crystal structures at room temperature of all of the members of the series are now solved, showing the existence of two polymorphic forms in the room temperature crystal phase, different to short and long-chain members. Only nonanoate and decanoate present both forms, and this polymorphism is proven to be monotropic. At higher temperature, these compounds present a solid mesophase, defined as rotator, a liquid crystal phase and a liquid phase, all of which have a similar local arrangement. Since some lead(ii) soaps appear as degradation compounds in oil paintings, the solved crystal structures of lead(ii) soaps can now be used as fingerprints for their detection using X-ray diffraction. Pair distribution function analysis on these compounds is very similar in the same phases and mesophases for the different members, showing the same short range order. This observation suggests that this technique could also be used in the detection of these compounds in disordered phases or in the initial stages of formation in paintings.

9.
Clin. transl. oncol. (Print) ; 19(1): 119-124, ene. 2017. tab, graf
Artículo en Inglés | IBECS | ID: ibc-159126

RESUMEN

Purpose. Immunotherapy (IT) agents and BRAF inhibitors (BRAFi) are effective treatments for patients with advanced BRAF-mutant melanoma although the optimal sequence remains to be elucidated. The aim of this study was to compare the outcomes of two different cohorts of patients treated with BRAFi first, then IT or the reverse sequence. Patients and methods. This is a retrospective study on two groups of patients: a cohort was treated first with BRAFi followed by immunotherapy (BRAFi-IT) and the other cohort with the reverse sequence (IT-BRAFi). Baseline characteristics and clinical outcomes were compared between the two cohorts. Results. A total of 25 patients were included in the study. Sixteen patients were given BRAFi-IT sequence and nine received IT-BRAFi sequence. No differences were observed in the characteristics of patients prior to each treatment between cohorts. Objective response rate (ORR) achieved by BRAFi were not different among groups. ORR achieved by IT was higher when administered after BRAFi (43.8 vs 0 %). Survival rates at 1-2 years were similar in both cohorts and median overall survival was not different for BRAFi-IT and IT-BRAFi (log rank test p = 0.97). Conclusions. No differences were observed in OS between the two cohorts. These results support the indistinct use of IT or BRAFi as initial treatment in patients with metastatic BRAF-mutant melanoma, although higher rate of response to IT was observed when administered after BRAFi. Prospective randomized clinical trials are needed on this issue (AU)


No disponible


Asunto(s)
Humanos , Masculino , Femenino , Melanoma/diagnóstico , Melanoma/inmunología , Melanoma/terapia , Inmunoterapia/métodos , Inmunoterapia , Proteínas Mutantes/análisis , Estudios de Cohortes , Estudios Retrospectivos , 24960 , Estimación de Kaplan-Meier
10.
Clin Transl Oncol ; 19(1): 119-124, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-27147251

RESUMEN

PURPOSE: Immunotherapy (IT) agents and BRAF inhibitors (BRAFi) are effective treatments for patients with advanced BRAF-mutant melanoma although the optimal sequence remains to be elucidated. The aim of this study was to compare the outcomes of two different cohorts of patients treated with BRAFi first, then IT or the reverse sequence. PATIENTS AND METHODS: This is a retrospective study on two groups of patients: a cohort was treated first with BRAFi followed by immunotherapy (BRAFi-IT) and the other cohort with the reverse sequence (IT-BRAFi). Baseline characteristics and clinical outcomes were compared between the two cohorts. RESULTS: A total of 25 patients were included in the study. Sixteen patients were given BRAFi-IT sequence and nine received IT-BRAFi sequence. No differences were observed in the characteristics of patients prior to each treatment between cohorts. Objective response rate (ORR) achieved by BRAFi were not different among groups. ORR achieved by IT was higher when administered after BRAFi (43.8 vs 0 %). Survival rates at 1-2 years were similar in both cohorts and median overall survival was not different for BRAFi-IT and IT-BRAFi (log rank test p = 0.97). CONCLUSIONS: No differences were observed in OS between the two cohorts. These results support the indistinct use of IT or BRAFi as initial treatment in patients with metastatic BRAF-mutant melanoma, although higher rate of response to IT was observed when administered after BRAFi. Prospective randomized clinical trials are needed on this issue.


Asunto(s)
Anticuerpos Monoclonales/uso terapéutico , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Inmunoterapia , Melanoma/tratamiento farmacológico , Mutación/genética , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas B-raf/antagonistas & inhibidores , Proteínas Proto-Oncogénicas B-raf/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Estudios de Seguimiento , Humanos , Masculino , Melanoma/inmunología , Melanoma/patología , Persona de Mediana Edad , Estadificación de Neoplasias , Pronóstico , Estudios Retrospectivos , Tasa de Supervivencia , Adulto Joven
11.
Radiologia ; 59(4): 355-358, 2017.
Artículo en Inglés, Español | MEDLINE | ID: mdl-28012727

RESUMEN

Pseudoaneurysms of the uterine artery are an uncommon cause of severe gynecological bleeding secondary to surgical manipulation of the pelvis or to instrumental delivery. The different imaging techniques are of vital importance in the diagnosis. Angiography is the technique used for confirmation and also for treatment in many cases. Endovascular treatment by embolizing the pseudoaneurysm has become established as the treatment of choice, making it possible to avoid hysterectomy in women of childbearing age. This article presents two cases of gynecological bleeding due to pseudoaneurysms (one secondary to surgery and one secondary to childbirth) that were embolized in a novel way using cyanoacrylate.


Asunto(s)
Aneurisma Falso/diagnóstico por imagen , Aneurisma Falso/terapia , Embolización Terapéutica , Enbucrilato/uso terapéutico , Arteria Uterina , Vagina/irrigación sanguínea , Adulto , Femenino , Humanos , Adulto Joven
12.
Rev. esp. med. nucl. imagen mol. (Ed. impr.) ; 35(2): 88-95, mar.-abr. 2016. tab, ilus, graf
Artículo en Inglés | IBECS | ID: ibc-148914

RESUMEN

Objective. Metabolic tumour volume (MTV) and total lesion glycolysis (TLG) from 18F-FDG PET/CT are emerging prognostic biomarkers in various solid neoplasms. These volumetric parameters and the SUVmax have shown to be useful criteria for disease prognostication in preoperative and post-treatment epithelial ovarian cancer (EOC) patients. The purpose of this study was to evaluate the utility of 18F-FDG PET/CT measurements to predict survival in patients with recurrent EOC. Material and methods. Twenty-six patients with EOC who underwent a total of 31 18F-FDG PET/CT studies for suspected recurrence were retrospectively included. SUVmax and volumetric parameters whole-body MTV (wbMTV) and whole-body TLG (wbTLG) with a threshold of 40% and 50% of the SUVmax were obtained. Correlation between PET parameters and progression-free survival (PFS) and the survival analysis of prognostic factors were calculated. Results. Serous cancer was the most common histological subtype (76.9%). The median PFS was 12.5 months (range 10.7-20.6 months). Volumetric parameters showed moderate inverse correlation with PFS but there was no significant correlation in the case of SUVmax. The correlation was stronger for first recurrences. By Kaplan-Meier analysis and log-rank test, wbMTV 40%, wbMTV 50% and wbTLG 50% correlated with PFS. However, SUVmax and wbTLG 40% were not statistically significant predictors for PFS. Conclusion. Volumetric parameters wbMTV and wbTLG 50% measured by 18F-FDG PET/CT appear to be useful prognostic predictors of outcome and may provide valuable information to individualize treatment strategies in patients with recurrent EOC (AU)


Objetivo. El metabolic tumour volume (MTV) y la total lesion glycolysis (TLG) obtenidos de la 18F-FDG PET/TC son biomarcadores pronósticos emergentes en varias neoplasias. Estos parámetros volumétricos junto con el SUVmax son útiles para determinar el pronóstico preoperatorio y post-tratamiento de las pacientes con cáncer epitelial de ovario (CEO). El objetivo fue determinar la utilidad de los parámetros de la 18F-FDG PET/TC para predecir la supervivenvia de las pacientes con CEO recurrente. Material y métodos. Se incluyeron retrospectivamente 26 pacientes con CEO a las que se les realizó 31 estudios 18F-FDG PET/TC por sospecha de recidiva. Se obtuvo el valor del SUVmax, whole-body MTV (wbMTV) y whole-body TLG (wbTLG) con un umbral del 40% y 50% del SUVmax. Se estimó la correlación entre los parámetros PET y el intervalo libre de progresión (ILP) y se realizó análisis de supervivencia segun factores pronósticos. Resultados. El subtipo histológico más frecuente fue cáncer seroso (76,9%). La mediana del ILP fue 12,5 meses (rango 10,7-20,6 meses). Se observó correlación inversa moderada entre los parámetros volumétricos e ILP, sin evidenciar correlación significativa con SUVmax. La correlación fue más fuerte para primeras recidivas. Las curvas de supervivencia mostraron correlación entre wbMTV 40%, wbMTV 50% y wbTLG 50% con ILP. SUVmax y wbTLG 40% no fueron predictores de ILP de forma estadísticamente significativa. Conclusión. Los parámetros wbMTV y wbTLG 50% de la 18F-FDG PET/TC podrían utilizarse como factores pronósticos ofreciendo una valiosa información para individualizar el tratamiento de las pacientes con CEO recurrente (AU)


Asunto(s)
Humanos , Femenino , Adulto , Persona de Mediana Edad , Neoplasias Ováricas , Pronóstico , Fluorodesoxiglucosa F18 , Tomografía de Emisión de Positrones/métodos , Tomografía de Emisión de Positrones , Ovario/anatomía & histología , Ovario/patología , Ovario , Epitelio/patología , Epitelio , Neoplasias Glandulares y Epiteliales , Estudios Retrospectivos
13.
Arch Oral Biol ; 63: 93-105, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26745819

RESUMEN

OBJECTIVES: We studied artificial dentin lesions in human teeth generated by lactate and acetate buffers (pH 5.0), the two most abundant acids in caries. The objective of this study was to determine differences in mechanical properties, mineral density profiles and ultrastructural variations of two different artificial lesions with the same approximate depth. METHODS: 0.05M (pH 5.0) acetate or lactate buffer was used to create 1) 180µm-deep lesions in non-carious human dentin blocks (acetate 130h; lactate 14days); (2) demineralized, ∼180µm-thick non-carious dentin discs (3 weeks). We performed nanoindentation to determine mechanical properties across the hydrated lesions, and micro X-ray computed tomography (MicroXCT) to determine mineral profiles. Ultrastructure in lesions was analyzed by TEM/selected area electron diffraction (SAED). Demineralized dentin discs were analyzed by small angle X-ray scattering (SAXS). RESULTS: Diffusion-dominated demineralization was shown based on the linearity between lesion depths versus the square root of exposure time in either solution, with faster kinetics in acetate buffer. Nanoindentation revealed lactate induced a significantly sharper transition in reduced elastic modulus across the lesions. MicroXCT showed lactate demineralized lesions had swelling and more disorganized matrix structure, whereas acetate lesions had abrupt X-ray absorption near the margin. At the ultrastructural level, TEM showed lactate was more effective in removing minerals from the collagenous matrix, which was confirmed by SAXS analysis. CONCLUSIONS: These findings indicated the different acids yielded lesions with different characteristics that could influence lesion formation resulting in their distinct predominance in different caries activities, and these differences may impact strategies for dentin caries remineralization.


Asunto(s)
Acetatos/farmacocinética , Dentina/ultraestructura , Ácido Láctico/farmacocinética , Desmineralización Dental , Acetatos/química , Fenómenos Biomecánicos , Módulo de Elasticidad , Dureza , Humanos , Concentración de Iones de Hidrógeno , Técnicas In Vitro , Ácido Láctico/química , Microscopía Electrónica de Transmisión , Tercer Molar , Dispersión del Ángulo Pequeño , Microtomografía por Rayos X
14.
Rev Esp Med Nucl Imagen Mol ; 35(2): 88-95, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26541072

RESUMEN

OBJECTIVE: Metabolic tumour volume (MTV) and total lesion glycolysis (TLG) from (18)F-FDG PET/CT are emerging prognostic biomarkers in various solid neoplasms. These volumetric parameters and the SUVmax have shown to be useful criteria for disease prognostication in preoperative and post-treatment epithelial ovarian cancer (EOC) patients. The purpose of this study was to evaluate the utility of (18)F-FDG PET/CT measurements to predict survival in patients with recurrent EOC. MATERIAL AND METHODS: Twenty-six patients with EOC who underwent a total of 31 (18)F-FDG PET/CT studies for suspected recurrence were retrospectively included. SUVmax and volumetric parameters whole-body MTV (wbMTV) and whole-body TLG (wbTLG) with a threshold of 40% and 50% of the SUVmax were obtained. Correlation between PET parameters and progression-free survival (PFS) and the survival analysis of prognostic factors were calculated. RESULTS: Serous cancer was the most common histological subtype (76.9%). The median PFS was 12.5 months (range 10.7-20.6 months). Volumetric parameters showed moderate inverse correlation with PFS but there was no significant correlation in the case of SUVmax. The correlation was stronger for first recurrences. By Kaplan-Meier analysis and log-rank test, wbMTV 40%, wbMTV 50% and wbTLG 50% correlated with PFS. However, SUVmax and wbTLG 40% were not statistically significant predictors for PFS. CONCLUSION: Volumetric parameters wbMTV and wbTLG 50% measured by (18)F-FDG PET/CT appear to be useful prognostic predictors of outcome and may provide valuable information to individualize treatment strategies in patients with recurrent EOC.


Asunto(s)
Recurrencia Local de Neoplasia/diagnóstico por imagen , Neoplasias Ováricas/diagnóstico por imagen , Tomografía Computarizada por Tomografía de Emisión de Positrones , Femenino , Humanos , Imagen Multimodal , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/mortalidad , Recurrencia Local de Neoplasia/patología , Neoplasias Ováricas/metabolismo , Neoplasias Ováricas/mortalidad , Neoplasias Ováricas/patología , Tomografía de Emisión de Positrones , Pronóstico , Estudios Retrospectivos , Tomografía Computarizada por Rayos X , Carga Tumoral
15.
Radiología (Madr., Ed. impr.) ; 57(5): 402-411, sept.-oct. 2015. tab, ilus
Artículo en Español | IBECS | ID: ibc-141045

RESUMEN

Objetivo. Analizar la eficacia y seguridad del procedimiento para colocar las prótesis autoexpandibles de colon. Evaluar los factores asociados a complicaciones. Realizar un análisis dosimétrico del procedimiento. Material y métodos. Realizamos un estudio descriptivo retrospectivo unicéntrico de 478 procedimientos para colocar prótesis metálicas autoexpandibles de colon. Se insertaron 423 prótesis de nitinol y 79 de acero inoxidable. Incluimos todas las obstrucciones de colon, 446 de etiología maligna y 8 de causa benigna. Excluimos los pacientes con perforación intestinal, hemorragia grave del colon, esperanza de vida corta y lesiones situadas a menos de 5 cm del ano. Analizamos el éxito técnico, éxito clínico, las complicaciones durante el seguimiento y recogimos los datos dosimétricos. Resultados. Se obtuvo éxito técnico en un 92,26% (n = 441), éxito clínico en un 78,45% (n = 375) y un porcentaje de complicaciones durante el seguimiento del 18,5%. Las prótesis de acero tuvieron más complicaciones (OR: 3,2; IC 95%: 1,8-5,7). El valor medio de producto dosis por área fue 35 Gy.cm2. El de tiempo de fluoroscopia (p = 0,001), producto dosis por área (p = 0,029) y kerma (p = 0,001) fueron mayores si el procedimiento fue realizado exclusivamente por fluoroscopia, en vez de conjuntamente por el endoscopista y el radiólogo intervencionista. Conclusión. El procedimiento para colocar prótesis autoexpandibles de colon es eficaz y seguro, con una tasa aceptable de complicaciones. Las dosis de radiación fueron bajas, con menos dosis y tiempos de fluoroscopia cuando el procedimiento se realizó de manera conjunta con el endoscopista (AU)


Objective. To analyze the efficacy and safety of the procedure for placing self-expanding stents in the colon. To evaluate the factors associated with complications. To analyze the dose of radiation delivered in the procedure. Material and methods. This was a retrospective descriptive study of 478 procedures done at a single center to place self-expanding metallic stents in the colon. A total of 423 nitinol stents and 79 stainless steel stents were placed. We included all colonic obstructions, of which 446 had malignant causes and 8 had benign causes. We excluded patients with intestinal perforation, severe colonic bleeding, short life expectancy, or lesions located less than 5 cm from the anus. We collected the dosimetric data and analyzed the technical success, clinical success, and complications during follow-up. Results. The procedure was a technical success in 92.26% of cases (n = 441) and a clinical success in 78.45% (n = 375); complications occurred during follow-up in 18.5% of cases. Complications occurred more frequently with the stainless steel stents than with the nitinol stents (OR: 3.2; 95% CI: 1.8-5.7). The mean value of the dose area product was 35 Gy*cm2. When instead of being done by the interventional radiologist working together with an endoscopist the procedure was done exclusively by the interventional radiologist, the time under fluoroscopy (p = 0.001), dose area product (p = 0.029), and kinetic energy released per unit mass (p = 0.001) were greater. Conclusion. The procedure for placing self-expanding colonic stents is efficacious and safe with an acceptable rate of complications. The doses of radiation delivered were low, and the radiation doses and time under fluoroscopy were lower when the procedure was done together with an endoscopist (AU)


Asunto(s)
Femenino , Humanos , Masculino , Prótesis e Implantes/tendencias , Prótesis e Implantes , Radiometría/métodos , Dosimetría/métodos , Fluoroscopía/métodos , Resultado del Tratamiento , Evaluación de Eficacia-Efectividad de Intervenciones , Estudios Retrospectivos , Carcinoma/cirugía , Carcinoma
16.
Radiologia ; 57(4): 321-5, 2015.
Artículo en Español | MEDLINE | ID: mdl-25074034

RESUMEN

OBJECTIVE: To study the clinical usefulness of ultrasound-guided alcohol sclerosis as a treatment alternative to surgical intervention for breast fistulas. MATERIAL AND METHODS: This was a retrospective study of data collected in a hospital breast unit over a three-year period (January 2011 through December 2013). The procedure consists of introducing a sclerosing solution into the lumen of the breast fistula under ultrasound guidance. All cases were reviewed by a multidisciplinary committee; patients were offered ultrasound-guided alcohol sclerosis as a first treatment option with surgical intervention as a rescue therapy for those with unsatisfactory outcomes. RESULTS: Ten fistulas were treated in 9 women (median age, 33 y; interquartile range 18.5 y). Five patients (50%) attributed the clinical findings to recurrent mastitis, four (40%) to a previous surgical intervention, and one (10%) to lactation. Seven patients (78%) were smokers. The procedure was well tolerated: nine patients (90%) rated the pain as one or 2 (mild pain) on a visual analogue scale. There were no immediate complications. The response to treatment was considered excellent (absence of secretion and complete closure) in eight fistulas (80%). CONCLUSION: Ultrasound-guided alcohol sclerosis achieved excellent outcomes in 80% of cases and is a viable alternative to surgical treatment.


Asunto(s)
Enfermedades de la Mama/terapia , Etanol/administración & dosificación , Fístula/terapia , Soluciones Esclerosantes/administración & dosificación , Adulto , Femenino , Humanos , Estudios Retrospectivos
17.
Radiologia ; 57(5): 402-11, 2015.
Artículo en Inglés, Español | MEDLINE | ID: mdl-25443436

RESUMEN

OBJECTIVE: To analyze the efficacy and safety of the procedure for placing self-expanding stents in the colon. To evaluate the factors associated with complications. To analyze the dose of radiation delivered in the procedure. MATERIAL AND METHODS: This was a retrospective descriptive study of 478 procedures done at a single center to place self-expanding metallic stents in the colon. A total of 423 nitinol stents and 79 stainless steel stents were placed. We included all colonic obstructions, of which 446 had malignant causes and 8 had benign causes. We excluded patients with intestinal perforation, severe colonic bleeding, short life expectancy, or lesions located less than 5 cm from the anus. We collected the dosimetric data and analyzed the technical success, clinical success, and complications during follow-up. RESULTS: The procedure was a technical success in 92.26% of cases (n=441) and a clinical success in 78.45% (n=375); complications occurred during follow-up in 18.5% of cases. Complications occurred more frequently with the stainless steel stents than with the nitinol stents (OR: 3.2; 95% CI: 1.8-5.7). The mean value of the dose area product was 35 Gy*cm(2). When instead of being done by the interventional radiologist working together with an endoscopist the procedure was done exclusively by the interventional radiologist, the time under fluoroscopy (p=0.001), dose area product (p=0.029), and kinetic energy released per unit mass (p=0.001) were greater. CONCLUSION: The procedure for placing self-expanding colonic stents is efficacious and safe with an acceptable rate of complications. The doses of radiation delivered were low, and the radiation doses and time under fluoroscopy were lower when the procedure was done together with an endoscopist.


Asunto(s)
Enfermedades del Colon/cirugía , Neoplasias del Colon/cirugía , Obstrucción Intestinal/cirugía , Complicaciones Posoperatorias/epidemiología , Stents Metálicos Autoexpandibles , Adulto , Anciano , Anciano de 80 o más Años , Neoplasias del Colon/complicaciones , Femenino , Humanos , Obstrucción Intestinal/etiología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/etiología , Estudios Retrospectivos , Factores de Tiempo , Resultado del Tratamiento
18.
Nutr. hosp ; 27(6): 2133-2138, nov.-dic. 2012. ilus, tab
Artículo en Español | IBECS | ID: ibc-112203

RESUMEN

La homocistinuria es un error congénito del metabolismo de la metionina que conduce al acúmulo de metionina y de su principal metabolito, homocisteína, en plasma, orina y tejidos. El acúmulo de homocisteína posee toxicidad sobre los sistemas óseo (osteoporosis), ocular (luxación del cristalino), nervioso (convulsiones, alteraciones psiquiátricas) y vascular (accidentes cerebrovasculares, enfermedad cardiovascular). Presentamos 2 casos de homocistinuria en 2 pacientes hermanos y, a continuación, revisamos las estrategias terapéuticas disponibles (AU)


Homocystinuria is a congenital disorder of methyonine metabolism that leads to increased plasmatic, urinary and tissue deposits of methyonine and its main metabolite: homocysteine. Homocysteine deposits are toxic for the skeletal system (osteoporosis), the eyes (lens dislocation), central nervous system (seizures, psychiatric disorders) and also induce vascular damage (stroke and other cardiovascular events). This article reports two patients with homocystinuria in two siblings, followed by a concise review on the therapeutic strategies available for this disorder (AU)


Asunto(s)
Humanos , Masculino , Adulto Joven , Adulto , Homocistinuria/dietoterapia , Metionina , Vitamina B 6/uso terapéutico , Cistina/uso terapéutico , Ácido Fólico/uso terapéutico , Betaína/uso terapéutico
19.
Nutr Hosp ; 27(6): 2133-8, 2012.
Artículo en Español | MEDLINE | ID: mdl-23588468

RESUMEN

Homocystinuria is a congenital disorder of methyonine metabolism that leads to increased plasmatic, urinary and tissue deposits of methyonine and its main metabolite: homocysteine. Homocysteine deposits are toxic for the skeletal system (osteoporosis), the eyes (lens dislocation), central nervous system (seizures, psychiatric disorders) and also induce vascular damage (stroke and other cardiovascular events). This article reports two patients with homocystinuria in two siblings, followed by a concise review on the therapeutic strategies available for this disorder.


Asunto(s)
Homocistinuria/dietoterapia , Adulto , Dieta , Homocisteína/sangre , Homocistinuria/sangre , Humanos , Masculino , Metionina/metabolismo , Tetrahidrofolato Deshidrogenasa/metabolismo , Adulto Joven
20.
Actas Urol Esp ; 34(2): 181-5, 2010 Feb.
Artículo en Español | MEDLINE | ID: mdl-20403283

RESUMEN

OBJECTIVE: Adrenal conditions requiring surgery are uncommon and are usually seen in several surgical departments. Our experience in laparoscopic management of adrenal pathology after almost five years of use of laparoscopy for retroperitoneal conditions at our center is reported. MATERIALS AND METHODS: A total of 37 laparoscopic adrenalectomies were performed over 53 months for benign and malignant conditions. The transperitoneal approach was used in most cases (97%) because of the greater surgeon experience with this route. Pregnancy and suspected periadrenal infiltration were considered as absolute contraindications. RESULTS: Mean operating time was 90 minutes, mean intraoperative bleeding 80 ml, and mean hospital stay was 2 days. The main complication was one death. A malignancy was found in 4 patients (10%), while all other patients (90%) had a benign condition, including 8 pheochromocytomas. CONCLUSIONS: Laparoscopy is considered to be the gold standard for benign adrenal conditions. When the malignant mass is a single metastasis from a primary tumor, the laparoscopic approach appears to be reliable. When the malignant lesion is a primary adrenal tumor, laparoscopic management is more controversial, although the results reported by experienced surgeons in their series appear to be adequate.


Asunto(s)
Adrenalectomía/métodos , Laparoscopía/métodos , Adenoma/cirugía , Enfermedades de las Glándulas Suprarrenales/cirugía , Neoplasias de las Glándulas Suprarrenales/secundario , Neoplasias de las Glándulas Suprarrenales/cirugía , Adrenalectomía/estadística & datos numéricos , Adulto , Anciano , Carcinoma/secundario , Carcinoma/cirugía , Contraindicaciones , Síndrome de Cushing/cirugía , Quistes/cirugía , Femenino , Humanos , Hiperaldosteronismo/cirugía , Laparoscopía/estadística & datos numéricos , Masculino , Persona de Mediana Edad , Mielolipoma/cirugía , Feocromocitoma/cirugía , Embarazo , Complicaciones del Embarazo/cirugía , Estudios Retrospectivos
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