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1.
Nature ; 563(7731): 365-368, 2018 11.
Artículo en Inglés | MEDLINE | ID: mdl-30429552

RESUMEN

Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known2,3 and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging4-6, astrometry7,8 and direct imaging9, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard's star, making it an excellent target for direct imaging and astrometric observations in the future.

2.
Langmuir ; 39(7): 2761-2770, 2023 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-36753691

RESUMEN

The behaviour of CTAB adsorbed on polycrystalline gold electrodes has been studied using a combination of spectroelectrochemical methods. The results indicate that the formation of the layer is the consequence of the precipitation of the CTAB micelles on the electrode surface as bromide ions, which stabilize the micelles, are replaced by perchlorate anions. This process leads to the formation of CTA+ layers in which perchlorate ions are intercalated, in which the adlayer suffers a continuous rearrangement that leads to the formation of micro-dominions of different types of hydrogen-bonded water populations throughout the adlayer. After prolonged cycling, a stable situation is reached. Under these conditions, water molecules permeate through the adlayer toward the electrode surface at potentials positive of the potential of zero charge, due to the repulsion between the CTA+ layer and the positive charge of the electrode.

3.
Acta Chir Belg ; 123(3): 231-237, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34445925

RESUMEN

INTRODUCTION: The need to care for patients with emergency symptoms still continues during the COVID-19 pandemic. The number of emergency surgery procedures performed in Spanish hospitals decreased significantly during the first wave of COVID-19. PATIENTS AND METHODS: We performed a retrospective cohort study comparing the emergency surgery activity in a Spanish tertiary Hospital during the COVID-19 pandemic and emergency surgery activity registered in 2019 during the equivalent time period. RESULTS: A total of 1802 patients were included in control group (CG) versus 756 in pandemic group (PG). Mean number of patients who underwent emergency surgery during the control and pandemic periods was 3.42 patients per day, in contrast to 1.62 during the pandemic period, which represents a 52.6% decrease in emergency surgery activity. During the pandemic period, most of the patients consulted after more than 72 h of symptoms, representing a delay in presenting in the ER of 23.7% when compared to CG. Surgeries due to complications from previous elective procedures decreased (12% vs. 6.1%) in PG, probably because elective procedures are being postponed. We had a 13.1% COVID-19 positivity rate. Morbidity was higher during pandemic (52.5% vs. 35.2%). Mortality rates in patients undergoing emergency surgery was higher in PG (12.1% vs. 4.8%). CONCLUSIONS: The impact of the first wave of COVID-19 in emergency surgery activity has been profound. A significant reduction in emergency surgery was observed, along with longer time periods between patients' onset of symptoms and their arrival at the Emergency Department. Higher morbidity was also observed during the pandemic period.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Estudios de Cohortes , Centros de Atención Terciaria , SARS-CoV-2 , Estudios Retrospectivos , Pandemias , Servicio de Urgencia en Hospital
4.
Ecotoxicol Environ Saf ; 187: 109836, 2020 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-31675504

RESUMEN

Toxicity of 13 ionic liquids (ILs) corresponding to different families were studied by inhibition respiration assays (15 min) using activated sludge. Toxicity increased as increasing the number of carbons in the alkyl-chain of imidazolium-based ILs, with EC50 values from 4.19 to 0.17 for 1-ethyl-3-methylimidazolium chloride ([Emim][Cl]) and 1-octyl-3-methylimidazolium chloride ([Omim][Cl]), respectively. An increase in toxicity was observed for aromatic-based ILs (pyridinium- and imidazolium-based ILs) due to the hydrophobic character of the head groups in comparison with linear structures as phosphonium and ammonium cations. Among to the anions studied fixing [Emim]+ as cation, [HSO4]- and [NTf2]- presented low EC50 values (0.34 mM and 1.69 mM, respectively) while [Cl]- and [EtSO4]- were considered harmless anions due to the hydrophilic character of chloride and the organic nature of [EtSO4]-. ILs toxicity/inhibition was determined by adding a biodegradable compound and measuring the sludge response after being in contact with the ILs for at least 15 h. The exposure of sewage sludge to ILs for more than 15 min used in short inhibition assays caused more toxic effect on microorganisms, even for [Choline][NTf2], previously defined as practically harmless (EC50 = 2.79 mM). Biodegradability assays confirmed the biodegradable nature of choline cation, related with TOC conversion of 40%, only due to cation consumption. No oxygen consumption or even lysis of microbial cells was observed for Tetrabutylammonium bis(trifluoromethylsulfonyl)imide and for 1-Ethyl-3-methylimidazolium hydrogensulphate due to the presence of anions previously defined as hazardous ([NTf2]- and [HSO4]-), maintaining their recalcitrant character to sewage systems.


Asunto(s)
Imidazoles/toxicidad , Líquidos Iónicos/toxicidad , Aguas del Alcantarillado/microbiología , Aniones , Biodegradación Ambiental , Cationes , Interacciones Hidrofóbicas e Hidrofílicas , Imidazoles/química , Líquidos Iónicos/química , Estructura Molecular
5.
J Periodontal Res ; 53(3): 457-466, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29516514

RESUMEN

BACKGROUND AND OBJECTIVE: Little is known about the initiation of dysbiosis in oral biofilms, a topic of prime importance for understanding the etiology of, and preventing, periodontitis. The aim of this study was to evaluate the effect of different concentrations of crevicular and salivary peroxidase and catalase on dysbiosis in multispecies biofilms in vitro. MATERIAL AND METHODS: The spotting technique was used to identify the effect of different concentrations of myeloperoxidase, lactoperoxidase, erythrocyte catalase, and horseradish peroxidase in salivary and crevicular fluid on the inhibitory effect of commensals on pathobiont growth. Vitality-quantitative real-time PCR was performed to quantify the dysbiotic effect of the peroxidases (adjusted to concentrations found in periodontal health, gingivitis, and periodontitis) on multispecies microbial communities. RESULTS: Agar plate and multispecies ecology experiments showed that production of hydrogen peroxide (H2 O2 ) by commensal bacteria decreases pathobiont growth and colonization. Peroxidases at concentrations found in crevicular fluid and saliva neutralized this inhibitory effect. In multispecies communities, myeloperoxidase, at the crevicular fluid concentrations found in periodontitis, resulted in a 1-3 Log increase in pathobionts when compared with the crevicular fluid concentrations found in periodontal health. The effect of salivary lactoperoxidase and salivary myeloperoxidase concentrations was, in general, similar to the effect of crevicular myeloperoxidase concentrations. CONCLUSIONS: Commensal species suppress pathobionts by producing H2 O2 . Catalase and peroxidases, at clinically relevant concentrations, can neutralize this effect and thereby can contribute to dysbiosis by allowing the outgrowth of pathobionts.


Asunto(s)
Bacterias/efectos de los fármacos , Biopelículas/efectos de los fármacos , Disbiosis/etnología , Peroxidasas/metabolismo , Peroxidasas/farmacología , Bacterias/clasificación , Bacterias/metabolismo , Reactores Biológicos , Catalasa/análisis , Eritrocitos/metabolismo , Líquido del Surco Gingival/química , Líquido del Surco Gingival/enzimología , Gingivitis/complicaciones , Gingivitis/microbiología , Peroxidasa de Rábano Silvestre/análisis , Humanos , Peróxido de Hidrógeno/metabolismo , Lactoperoxidasa/metabolismo , Lactoperoxidasa/farmacología , Microbiota , Periodontitis/complicaciones , Periodontitis/microbiología , Peroxidasa/metabolismo , Peroxidasa/farmacología , Saliva/química , Saliva/enzimología
6.
Cereb Cortex ; 27(9): 4314-4325, 2017 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-27522079

RESUMEN

Individual experiences often overlap in their content, presenting opportunities for rapid generalization across them. In this study, we show in 2 independent experiments that integrative encoding-the ability to form individual and across memory representations during online encoding-is supported by 2 distinct neurophysiological responses. Brain potential is increased gradually during encoding and fit to a trial level memory measure for individual episodes, whereas neural oscillations in the theta range (4-6 Hz) emerge later during learning and predict participants' generalization performance in a subsequent test. These results suggest that integrative encoding requires the recruitment of 2 separate neural mechanisms that, despite their co-occurrence in time, differ in their underlying neural dynamics, reflect different brain learning rates and are supportive of the formation of opposed memory representations, individual versus across-event episodes.


Asunto(s)
Encéfalo/fisiología , Aprendizaje/fisiología , Memoria Episódica , Ritmo Teta/fisiología , Adulto , Mapeo Encefálico/métodos , Electroencefalografía/métodos , Femenino , Humanos , Masculino , Monitorización Neurofisiológica , Análisis y Desempeño de Tareas , Adulto Joven
7.
Antimicrob Agents Chemother ; 60(10): 5914-21, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27458229

RESUMEN

Severely burned patients have altered drug pharmacokinetics (PKs), but it is unclear how different they are from those in other critically ill patient groups. The aim of the present study was to compare the population pharmacokinetics of micafungin in the plasma and burn eschar of severely burned patients with those of micafungin in the plasma and peritoneal fluid of postsurgical critically ill patients with intra-abdominal infection. Fifteen burn patients were compared with 10 patients with intra-abdominal infection; all patients were treated with 100 to 150 mg/day of micafungin. Micafungin concentrations in serial blood, peritoneal fluid, and burn tissue samples were determined and were subjected to a population pharmacokinetic analysis. The probability of target attainment was calculated using area under the concentration-time curve from 0 to 24 h/MIC cutoffs of 285 for Candida parapsilosis and 3,000 for non-parapsilosis Candida spp. by Monte Carlo simulations. Twenty-five patients (18 males; median age, 50 years; age range, 38 to 67 years; median total body surface area burned, 50%; range of total body surface area burned, 35 to 65%) were included. A three-compartment model described the data, and only the rate constant for the drug distribution from the tissue fluid to the central compartment was statistically significantly different between the burn and intra-abdominal infection patients (0.47 ± 0.47 versus 0.15 ± 0.06 h(-1), respectively; P < 0.05). Most patients would achieve plasma PK/pharmacodynamic (PD) targets of 90% for non-parapsilosis Candida spp. and C. parapsilosis with MICs of 0.008 and 0.064 mg/liter, respectively, for doses of 100 mg daily and 150 mg daily. The PKs of micafungin were not significantly different between burn patients and intra-abdominal infection patients. After the first dose, micafungin at 100 mg/day achieved the PK/PD targets in plasma for MIC values of ≤0.008 mg/liter and ≤0.064 mg/liter for non-parapsilosis Candida spp. and Candida parapsilosis species, respectively.


Asunto(s)
Antifúngicos/farmacocinética , Equinocandinas/farmacocinética , Infecciones Intraabdominales/tratamiento farmacológico , Lipopéptidos/farmacocinética , Adulto , Anciano , Antifúngicos/sangre , Líquido Ascítico/efectos de los fármacos , Quemaduras/complicaciones , Quemaduras/microbiología , Enfermedad Crítica , Equinocandinas/sangre , Femenino , Humanos , Lipopéptidos/sangre , Masculino , Micafungina , Persona de Mediana Edad , Método de Montecarlo , Estudios Prospectivos , Distribución Tisular
8.
Med Intensiva ; 39(8): 467-76, 2015 Nov.
Artículo en Español | MEDLINE | ID: mdl-25798955

RESUMEN

OBJECTIVES: To determine the reasons of prescription, the characteristics of patients and factors that affected the outcome of critically ill patients treated with micafungin (MCF) during their stay in Spanish ICUs. MATERIAL AND METHODS: Observational, retrospective and multicenter study. Patients admitted to the ICU between March 2011 and October 2012 (20-month period) treated with MCF for any reason were included in the study. Severity of patients at the beginning of treatment was measured with the APACHE II, SOFA, Child-Pugh and MELD scores. Reasons for the use of MCF were classified as prophylaxis, preemptive treatment, empirical treatment and directed treatment. Continuous variables are expressed as mean and standard deviation or median, and categorical variables as percentages. A multivariate analysis was performed to identify variables related to intra-ICU mortality. RESULTS: The study population included 139 patients admitted to 19 Spanish ICUs, with a mean age of 57.3 (17.1) years, 89 (64%) men, with surgical (53.2%) and/or medical (44.6%) conditions, APACHE II score of 20.6 (7.7) and SOFA score of 8.4 (4.3), with 84.2% of patients requiring mechanical ventilation, 59% parenteral nutrition, 37.4% extrarenal depuration procedures and 37.4% treatment with steroids. MCF was indicated as empirical treatment of a proven infection in 51 (36.7%) cases, pre-emptive treatment in 50 (36%) especially as a result of the application of the Candida score (32 cases), directed treatment of fungal infection in 23 (16.5%) and as prophylactic treatment in 15 (10.8%) cases. In 108 (77%) cases, a daily dose of 100mg was administered, with a loading dose in only 9 cases (6.5%). The mean duration of treatment was 13.1 (13) days. A total of 59 (42.4%) patients died during their stay in the ICU and 16 after ICU discharge (hospital mortality 53.9%). Independent risk factors for intra-ICU mortality were the Child-Pugh score (OR 1.45, 95% CI 1.162-1.813; P=.001) and the MELD score (OR 1.05, 95% CI 1.011-1.099; P=.014). CONCLUSIONS: MCF is usually administered at a dose of 100mg/day, without loading dose and in 72.7% of cases as pre-emptive or empirical treatment. Factors that better predicted mortality were indicators of liver insufficiency at the time of starting treatment.


Asunto(s)
Antifúngicos/uso terapéutico , Cuidados Críticos/métodos , Equinocandinas/uso terapéutico , Lipopéptidos/uso terapéutico , Micosis/tratamiento farmacológico , Adulto , Anciano , Terapia Combinada , Femenino , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos , Tiempo de Internación , Fallo Hepático/complicaciones , Masculino , Micafungina , Persona de Mediana Edad , Micosis/prevención & control , Complicaciones Posoperatorias/tratamiento farmacológico , Estudios Retrospectivos , Índice de Severidad de la Enfermedad , España/epidemiología
9.
Phys Chem Chem Phys ; 15(42): 18671-7, 2013 Nov 14.
Artículo en Inglés | MEDLINE | ID: mdl-24072258

RESUMEN

The co-adsorption of CO and OH on two Pt stepped surfaces vicinal to the (111) orientation has been evaluated by means of density functional theory (DFT) calculations. Focusing on Pt(533) and Pt(221), which contain (100) and (111)-steps, respectively, we find that (111)-steps should be more reactive towards CO oxidation than surfaces containing (100)-steps. The DFT results are compared with electrochemical experiments on the CO adsorption and oxidation on these vicinal surfaces.

10.
Artículo en Inglés | MEDLINE | ID: mdl-37788763

RESUMEN

Pancreatic cancer is a disease with a poor prognosis, and overall survival has improved the least in the last 40 years of all cancers. Locally advanced pancreatic adenocarcinoma, without distant metastasis but with limiting vascular involvement, constitutes almost one third of these patients. This group is the focus of most research efforts to introduce treatments to increase surgical salvage rates and/or survival, with two main objectives: local control and prevention of systemic progression. Intratumoural treatment with phosphorus-32 microparticles, guided by echoendoscopy and combined with standard chemotherapy may have significant and clinically relevant benefits in these patients, and therefore a valuable treatment option in a disease where there is an urgent need to develop new therapies to help improve outcomes.


Asunto(s)
Adenocarcinoma , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/diagnóstico por imagen , Neoplasias Pancreáticas/tratamiento farmacológico , Adenocarcinoma/terapia , Adenocarcinoma/tratamiento farmacológico , Páncreas , Neoplasias Pancreáticas
11.
J Viral Hepat ; 19(10): 711-5, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22967102

RESUMEN

Transient elastography is a useful method to assess liver fibrosis, but uncertainties still exist regarding reliability and reproducibility of the technique. We aimed to improve knowledge on interobserver variability with the procedure and tried to find factors associated with such variability. This was a cross-sectional study to compare the results of transient elastography performed by two different operators, one test made just after the other. We assessed both results with correlation tests and with repeated parametric or nonparametric tests, as needed. We also carried out a multivariate analysis to find factors associated with discrepancy in the results obtained by the two operators. We included a total of 333 pairs of transient elastography tests, belonging to 274 different patients. A total of 325 pairs of tests (97.6%) were valid. Results of the first and the second tests were, respectively, median (and interquartile range) of direct measurement 6.2 (4.6-10.6) and 6.0 (4.4-10.1) kPa (P = 0.012), and mean ± standard deviation of log(10) of direct measurement 0.892 ± 0.316 and 0.871 ± 0.324 (P = 0.001). In 87 pairs of tests (26.7%), a discrepancy of at least 2 kPa between both results was found, and in 15 pairs of tests (4.6%), a discrepancy of at least 10 kPa was found. Discordance of at least one stage between both measurements was noted in 74 pairs of tests (22.8%). An association was found between higher stiffness and discrepancy between both operators (P < 0.001). Although transient elastography is a very convenient test to assess liver fibrosis in clinical practice, interobserver discrepancy in results is common and represents a significant problem with the technique. Discrepant results are more common in patients with higher values of stiffness.


Asunto(s)
Diagnóstico por Imagen de Elasticidad/métodos , Cirrosis Hepática/diagnóstico , Adulto , Estudios Transversales , Humanos , Persona de Mediana Edad , Variaciones Dependientes del Observador
12.
Artículo en Inglés | MEDLINE | ID: mdl-34752369

RESUMEN

INTRODUCTION: Adjuvant chemotherapy (CT) significally reduces the rate of relapse in +pN (stage III) colon cancer (CC) and in some pN0 (stage II) with risk factors such as pT4, vascular invasion V1, perineural invasion Pn1, and complicated tumors. However, unexpectedly, 20%-30% of pN0 present a relapse in the follow-up, which may suggest that the lymph node involvement was not discovered in the conventional histological study (CS), and its finding with a superstudy (SS) could increase the number of patients who would benefit from neoadjuvant CT. It is not possible to perform this SS in every lymph node (LN) from the specimen, but it is possible in a small group of LN which are representative of the N status (definition of sentinel node SN). The aim of our work is to state the representativeness of the SN and to analyze de number of patients who are suprastaged after the SS of the SN. MATERIAL AND METHODS: Prospective study of a series of patients who have undergone curative surgery for CC, to whom we perform selective biopsy of sentinel node (SBDN). Identification of SN was carried out with in vivo injection of the radiotracer, with ex vivo isolation of SN. Once the specimen is out, we take pictures of the surgical bed to rule out the presence of aberrant drainage routes, out of the routine oncological resection area. We performed the histological CS (Hematoxilin-Eosin stain (H-E) in conventional sections) in the rest of the LN from the mesocolon. In the SN we performed the CS and a SS with H-E in serial sections, immunohistochemistry (IHC) and molecular study with OSNA® (One Step Nucleic Acid Amplification). Diagnostic validity study od SBSN was carried out, defining the false negative (FN) as the negativity of the SN while other LN are positive (N+), as well as a valuation of the suprastaging due to the SS of the SN. RESULTS: We performed lymphatic map in 72 patients, finding the SN in 62 of them (87.3%). The 9 identification failures happened in the first 17 cases. We have not found aberrant drainage routes. A total of 1.164 LN were studied in the 62 patients (18.8 LN/patient), from which 145 are SN (2,34 SN/patient), having found 103 positive LN with the CS and 112 positive with the SS of SN (9+ LN more in 8 patients than detected with the CS). Positivity after CS in the SN group is 17.24% (25/145), while it is 8.53% in the rest (87/1.019) (P < .001). With the CS, 50% of the patients (31/62) were pN+ (4 are N+ exclusively in the SN), and after the SS of the SN, only 1 of the 31 pN0 patients (3.2%) becomes pN1a, with a definitive 51.6% of N+ in the whole series (32 N+ in the 62 patients) (5 are N+ exclusively in the SN). Exclusively with the SS of the SN, FN rate ("-SN, +others", meaning patients who are N+ having -SN) is 54.8% (17/31). With the SS of the SN, 8 of the 62 patients (12.9%) increase their total number of +LN: apart from the patient who turns from pN0 to pN1a, suprastaging from IIA to IIIB (and therefore increasing the total number of pN+ to 32), 5 of the 17 FN in the CS turns into positive (2 change the pN subindex and one is suprastaged from IIIB to IIIC), decreasing FN to 37.5% (12/32 cases). Besides, 2 patients whose SN is already positive in the CS increase the number of +SN after the SS of the SN, therefore both changing their pN subindex and one of them suprastaging from IIIB to IIIC. In summary, 8 patients increase the total number of positive SN after the SS (8/62, 12.9%), 5 of them changing the pN subindex (5/62, 12.9%), even if only 3 of them get suprastaged (3/62, 4.8%), among them the one who turns from pN0 to pN1a. CONCLUSION: Technique is valid and reproducible, with a high detection rate even with a high learning curve. It globally increases the number of affected LN in 12.9% of patients, having prognostic implications in 4.8% (suprastaging rate). Only 3.2% of pN0 patients in the CS turn to be +pN after the SS of the SN, with its therapeutic implications (prescription of adjuvant CT), which could be relevant when extrapolated to a big number of patients. The high FN rate (37.5%) prevents us from accepting the representativeness of SN as the global N status, but it is not clinically relevant in CC, as its aim is not to avoid lymphadenectomy, which remains mandatory (opposite to breast cancer or melanoma in which SN detection decides upon whether to perform or not the lymphadenectomy), but to decide which patients would benefit from adjuvant CT.


Asunto(s)
Neoplasias del Colon/diagnóstico por imagen , Neoplasias del Colon/patología , Ganglio Linfático Centinela/diagnóstico por imagen , Ganglio Linfático Centinela/patología , Quimioterapia Adyuvante , Neoplasias del Colon/tratamiento farmacológico , Humanos , Curva de Aprendizaje , Escisión del Ganglio Linfático , Terapia Neoadyuvante , Invasividad Neoplásica , Recurrencia Local de Neoplasia/prevención & control , Estadificación de Neoplasias/métodos , Técnicas de Amplificación de Ácido Nucleico , Estudios Prospectivos , Radioisótopos , Reproducibilidad de los Resultados , Factores de Riesgo , Biopsia del Ganglio Linfático Centinela/estadística & datos numéricos
13.
Artículo en Inglés, Español | MEDLINE | ID: mdl-33642258

RESUMEN

INTRODUCTION: Adjuvant chemotherapy (CT) significally reduces the rate of relapse in +pN (stage III) colon cancer and in some pN0 (stage II) with risk factors such as pT4, vascular invasion V1, perineural invasion Pn1, and complicated tumors. However, unexpectedly, 20-30% of pN0 present a relapse in the follow-up, which may suggest that the lymph node involvement was not discovered in the conventional histological study (CS), and its finding with a superstudy (SS) could increase the number of patients who would benefit from neoadjuvant CT. It is not possible to perform this SS in every lymph node (LN) from the specimen, but it is possible in a small group of LN which are representative of the N status (definition of sentinel node SN). The aim of our work is to state the representativeness of the SN and to analyze de number of patients who are suprastaged after the SS of the SN. MATERIAL AND METHODS: Prospective study of a series of patients who have undergone curative surgery for colon cancer, to whom we perform selective biopsy of sentinel node. Identification of SN was carried out with in vivo injection of the radiotracer, with ex vivo isolation of SN. Once the specimen is out, we take pictures of the surgical bed to rule out the presence of aberrant drainage routes, out of the routine oncological resection area. We performed the histological CS (hematoxilin-eosin stain in conventional sections) in the rest of the LN from the mesocolon. In the SN we performed the CS and a SS with hematoxilin-eosin in serial sections, immunohistochemistry (IHC) and molecular study with One Step Nucleic Acid Amplification (OSNA®). Diagnostic validity study od selective biopsy of sentinel node was carried out, defining the false negative (FN) as the negativity of the SN while other LN are positive (N+), as well as a valuation of the suprastaging due to the SS of the SN. RESULTS: We performed lymphatic map in 72 patients, finding the SN in 62 of them (87.3%). The 9 identification failures happened in the first 17 cases. We have not found aberrant drainage routes. A total of 1.164 LN were studied in the 62 patients (18.8 LN/ patient), from which 145 are SN (2,34 SN/ patient), having found 103 positive LN with the CS and 112 positive with the SS of SN (9 +LN more in 8 patients than detected with the CS). Positivity after CS in the SN group is 17.24% (25/145), while it is 8.53% in the rest (87/1.019) (p<.001). With the CS, 50% of the patients (31/62) were pN+ (4 are N+ exclusively in the SN), and after the SS of the SN, only 1 of the 31 pN0 patients (3.2%) becomes pN1a, with a definitive 51.6% of N+ in the whole series (32 N+ in the 62 patients) (5 are N+ exclusively in the SN). Exclusively with the SS of the SN, FN rate ("-SN, +others", meaning patients who are N+ having -SN) is 54.8% (17/31). With the SS of the SN, 8 of the 62 patients (12.9%) increase their total number of +LN: apart from the patient who turns from pN0 to pN1a, suprastaging from IIA to IIIB (and therefore increasing the total number of pN+ to 32), 5 of the 17 FN in the CS turns into positive (2 change the pN subindex and one is suprastaged from IIIB to IIIC), decreasing FN to 37.5% (12/32 cases). Besides, 2 patients whose SN is already positive in the CS increase the number of +SN after the SS of the SN, therefore both changing their pN subindex and one of them suprastaging from IIIB to IIIC. In summary, 8 patients increase the total number of positive SN after the SS (8/62, 12.9%), 5 of them changing the pN subindex (5/62, 12.9%), even if only 3 of them get suprastaged (3/62, 4.8%), among them the one who turns from pN0 to pN1a. CONCLUSION: Technique is valid and reproducible, with a high detection rate even with a high learning curve. It globally increases the number of affected LN in 12.9% of patients, having prognostic implications in 4.8% (suprastaging rate). Only 3.2% of pN0 patients in the CS turn to be +pN after the SS of the SN, with its therapeutic implications (prescription of adjuvant CT), which could be relevant when extrapolated to a big number of patients. The high FN rate (37.5%) prevents us from accepting the representativeness of SN as the global N status, but it is not clinically relevant in colon cancer, as its aim is not to avoid lymphadenectomy, which remains mandatory (opposite to breast cancer or melanoma in which SN detection decides upon whether to perform or not the lymphadenectomy), but to decide which patients would benefit from adjuvant CT.

14.
ESMO Open ; 6(5): 100279, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34607284

RESUMEN

BACKGROUND: KRAS is mutated in ∼30% of non-small-cell lung cancer (NSCLC) but it has also been identified as one of the mechanisms underlying resistance to tyrosine kinase inhibitors (TKIs) in EGFR-positive NSCLC patients. Novel KRAS inhibitors targeting KRAS p.G12C mutation have been developed recently with promising results. The proportion of EGFR-positive NSCLC tumours harbouring the KRAS p.G12C mutation upon disease progression is completely unexplored. MATERIALS AND METHODS: Plasma samples from 512 EGFR-positive advanced NSCLC patients progressing on a first first-line treatment with a TKI were collected. The presence of KRAS p.G12C mutation was assessed by digital PCR. RESULTS: Overall, KRAS p.G12C mutation was detected in 1.17% of the samples (n = 6). In two of these cases, we could confirm that the KRAS p.G12C mutation was not present in the pre-treatment plasma samples, supporting its role as an acquired resistance mutation. According to our data, KRASG12C patients showed similar clinicopathological characteristics to those of the rest of the study cohort and no statistically significant associations between any clinical features and the presence of the mutation were found. However, two out of six KRASG12C tumours harboured less common EGFR driver mutations (p.G719X/p.L861Q). All KRASG12C patients tested negative for the presence of p.T790M resistance mutation. CONCLUSIONS: The KRAS p.G12C mutation is detected in 1% of EGFR-positive NSCLC patients who progress on a first line with a TKI. All KRASG12C patients were negative for the presence of the p.T790M mutation and they did not show any distinctive clinical feature.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Carcinoma de Pulmón de Células no Pequeñas/genética , Receptores ErbB/genética , Humanos , Neoplasias Pulmonares/tratamiento farmacológico , Neoplasias Pulmonares/genética , Mutación , Inhibidores de Proteínas Quinasas/uso terapéutico , Proteínas Proto-Oncogénicas p21(ras)/genética
15.
Science ; 371(6533): 1038-1041, 2021 03 05.
Artículo en Inglés | MEDLINE | ID: mdl-33674491

RESUMEN

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

16.
J Nanosci Nanotechnol ; 9(4): 2256-73, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19437963

RESUMEN

Gold nanoparticles of different shapes/surface structures were synthesized and electrochemically characterized. An in-situ surface characterization of the Au nanoparticles, which was able to obtain qualitative information about the type and relative sizes of the different facets present in the surface of the Au nanoparticles, was carried out by using Pb Under Potential Deposition (UPD) in alkaline solutions as a surface sensitive tool. The results obtained show that the final atomic arrangement on the surface can be different from that expected from the bulk structure of the well-defined shape Au nanoparticles. In this way, the development of precise in-situ methods to measure the distribution of the different sites on the nanoparticle surface, as lead UPD on gold surfaces, is highlighted. Oxygen Reduction Reaction (ORR) was performed on the different Au nanoparticles. In agreement with the particular sensitivity of the oxygen reduction to the presence of Au(100) surface domains, cubic Au nanoparticles show much better electrocatalytic activity for ORR than small spherical particles and long nanorods, in agreement with the presence of a great fraction of (100) terrace sites on the surface of cubic gold nanoparticles.

17.
Actas Urol Esp (Engl Ed) ; 43(7): 337-347, 2019 Sep.
Artículo en Inglés, Español | MEDLINE | ID: mdl-31109736

RESUMEN

INTRODUCTION: In cases of persistent suspicion of prostate cancer (PC), repeat prostate biopsies (PB) are frequently performed in spite of their low yield. In the context of a negative PB, there is a microscopic scenario (MS), which we define as the group of recognizable non-neoplastic lesions. While some of these lesions seem to have a protective effect, the existence of others increases the risk of PC detection in posterior PB. The objective of this systematic review is to identify the lesions that may belong to the MS of a negative PB and analyse the current evidence of their association with the risk of detecting PC in subsequent PBs. EVIDENCE ACQUISITION: Two independent reviewers conducted a literature search on Medline, Embase and Central Cochrane with the following search terms: small acinar proliferation, ASAP, prostatic intraepithelial neoplasia, HGPIN, adjacent small atypical glands, pinatyp, atrophy, proliferative inflammatory atrophy, pia, prostatic inflammation, prostatitis and prostate cancer. 1,015 references were first identified, and 57 original articles were included in the study, following the PRISMA declaration and the PICO selection principles. EVIDENCE SYNTHESIS: Atypical small acinar proliferation is associated with PC detection in repeat PB with rates ranging between 32 and 48%. High-grade prostatic intraepithelial neoplasia (HGPIN) is related to PC in 13 to 42% of cases. Studies show that HGPIN, when multifocal, is a significant independent risk factor for PC. Prostatic atrophy, inflammatory proliferative atrophy and prostatic inflammation seem to act as protective factors on the detection of PC in repeat PB. On the other hand, the risk of PC detection reduces significantly in male patients with multifocal HGPIN and coexistent PIA. CONCLUSIONS: The MS of a negative PB may include atypical small acinar proliferation, HGPIN, prostatic atrophy, inflammatory proliferative atrophy and prostatic inflammation lesions, since they all seem to be associated with the risk of PC detection in repeat PB. This review has led us to create the hypothesis that the MS of a negative PB might be a valuable and useful tool when considering repeat PB.


Asunto(s)
Próstata/patología , Enfermedades de la Próstata/patología , Neoplasias de la Próstata/patología , Biopsia , Predicción , Humanos , Masculino , Medición de Riesgo
18.
Waste Manag ; 95: 620-627, 2019 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-31351649

RESUMEN

Fisheries are one of the main economic sectors affected by marine litter, which can damage gear, reduce catch, and require time to repair or clean nets. This study aims to evaluate the type and density of marine litter in two shallow fishing grounds in the NW Mediterranean Sea, both belonging to the Natura 2000 network. Moreover, it quantifies the fraction of marine litter within the total catch to help understand the potential influence of marine litter on fisheries. Two study areas were selected, one in the vicinity of urban populated areas and high navigational traffic and one in a rural site off an agricultural area. The urban area had more benthic marine litter (393 to 198 kg km-2) including clinker (residue from coal-burning steamships), fabric, plastics, and processed wood and accounting for up to 38% of the total catch. The rural area had far less marine litter (34-56 kg km-2), accounting for only 5% of the total catch. Marine litter may have potential negative effects on fisheries; thus we propose that government credit trading programs could be promoted to help recover litter from fishing catches, to reduce fishing costs and hazards to marine ecosystems.


Asunto(s)
Ecosistema , Residuos , Monitoreo del Ambiente , Explotaciones Pesqueras , Mar Mediterráneo , Plásticos
19.
Science ; 365(6460): 1441-1445, 2019 09 27.
Artículo en Inglés | MEDLINE | ID: mdl-31604272

RESUMEN

Surveys have shown that super-Earth and Neptune-mass exoplanets are more frequent than gas giants around low-mass stars, as predicted by the core accretion theory of planet formation. We report the discovery of a giant planet around the very-low-mass star GJ 3512, as determined by optical and near-infrared radial-velocity observations. The planet has a minimum mass of 0.46 Jupiter masses, very high for such a small host star, and an eccentric 204-day orbit. Dynamical models show that the high eccentricity is most likely due to planet-planet interactions. We use simulations to demonstrate that the GJ 3512 planetary system challenges generally accepted formation theories, and that it puts constraints on the planet accretion and migration rates. Disk instabilities may be more efficient in forming planets than previously thought.

20.
J Endocrinol Invest ; 31(7): 618-23, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18787380

RESUMEN

Papillary thyroid cancer (PTC) accounts for 80% of all thyroid malignancies, and genetic alterations associated to its etiology remain largely unknown. Chromosomal band 11q13 seems to be one of the most frequently amplified regions in human cancer, providing several candidate genes that need detailed characterization. The aim of our study was to investigate the existence of allelic imbalance at EMSY, CAPN5, and PAK1, as candidate genes within 11q13.5-q14 region using a single nucleotide polymorphism-based analysis. We selected a panel of 9 polymorphisms that were analyzed in 41 thyroid carcinoma samples, their contralateral non-pathological tissue and 178 controls from the general population. We did not detect allelic imbalance at these loci in our series. However, we observed a difference in the EMSY-haplotype distribution among PTC patients when compared to controls (odds ratio=2.00; p=0.02). We conclude that 11q13.5-q14 is not imbalanced in PTC, but there is evidence suggesting that EMSY might be of relevance in PTC etiology.


Asunto(s)
Desequilibrio Alélico , Calpaína/genética , Carcinoma Papilar/genética , Proteínas de Neoplasias/genética , Proteínas Nucleares/genética , Proteínas Represoras/genética , Neoplasias de la Tiroides/genética , Quinasas p21 Activadas/genética , Cromosomas Humanos Par 11 , Haplotipos , Humanos , Desequilibrio de Ligamiento , Polimorfismo de Nucleótido Simple
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