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Black phosphorus (bP) is a crystalline material that can be seen as an ordered stacking of two-dimensional layers, which results in outstanding anisotropic physical properties. The knowledge of its pressure (P)-temperature (T) phase diagram, and in particular, of its melting curve is fundamental for a better understanding of the synthesis and stability conditions of this element. Despite the numerous studies devoted to this subject, significant uncertainties remain regarding the determination of the position and slope of its melting curve. Here we measured the melting curve of bP in an extended P, T region from 0.10(3) to 5.05(40) GPa and from 914(25) to 1788(70) K, using in situ high-pressure and high-temperature synchrotron X-ray diffraction. We employed an original metrology based on the anisotropic thermoelastic properties of bP to accurately determine P and T. We observed a monotonic increase of the melting temperature with pressure and the existence of two distinct linear regimes below and above 1.35(15) GPa, with respective slopes of 348 ± 21 and of 105 ± 12 K·GPa-1. These correspond to the melting of bP toward the low-density liquid and the high-density liquid, respectively. The triple point at which solid bP and the two liquids meet is located at 1.35(15) GPa and 1350(25) K. In addition, we have characterized the solid phases after crystallization of the two liquids and found that, while the high-density liquid transforms back to solid bP, the low-density liquid crystallizes into a more complex, partly crystalline and partly amorphous solid. The X-ray diffraction pattern of the crystalline component could be indexed as a mixture of red and violet P.
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INTRODUCTION: Early-onset Alzheimer's disease (EOAD) shows a higher burden of neuropsychiatric symptoms than late-onset Alzheimer's disease (LOAD). We aim to determine the differences in the severity of neuropsychiatric symptoms and locus coeruleus (LC) integrity between EOAD and LOAD accounting for disease stage. METHODS: One hundred four subjects with AD diagnosis and 32 healthy controls were included. Participants underwent magnetic resonance imaging (MRI) to measure LC integrity, measures of noradrenaline levels in cerebrospinal fluid (CSF) and Neuropsychiatric Inventory (NPI). We analyzed LC-noradrenaline measurements and clinical and Alzheimer's disease (AD) biomarker associations. RESULTS: EOAD showed higher NPI scores, lower LC integrity, and similar levels of CSF noradrenaline compared to LOAD. Notably, EOAD exhibited lower LC integrity independently of disease stage. LC integrity negatively correlated with neuropsychiatric symptoms. Noradrenaline levels were increased in AD correlating with AD biomarkers. DISCUSSION: Decreased LC integrity negatively contributes to neuropsychiatric symptoms. The higher LC degeneration in EOAD compared to LOAD could explain the more severe neuropsychiatric symptoms in EOAD. HIGHLIGHTS: LC degeneration is greater in early-onset AD (EOAD) compared to late-onset AD. Tau-derived LC degeneration drives a higher severity of neuropsychiatric symptoms. EOAD harbors a more profound selective vulnerability of the LC system. LC degeneration is associated with an increase of cerebrospinal fluid noradrenaline levels in AD.
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In recent years, hydrogen has gained attention as a potential solution to replace fossil fuels, thus reducing greenhouse gas emissions. The development of ever improving hydrogen sensors is a topic that is constantly under study due to concerns about the inherent risk of leaks of this gas and potential explosions. In this work, a new, long-term, stable phosphorene-based sensor was developed for hydrogen detection. A simple functionalization of phosphorene using urea was employed to synthesize an air-stable material, subsequently used to prepare films for gas sensing applications, via the drop casting method. The material was deeply characterized by different techniques (scanning electron microscopy, X-ray diffraction, X-ray photoelectron, and Raman spectroscopy), and the stability of the material in a noninert atmosphere was evaluated. The phosphorene-based sensor exhibited high sensitivity (up to 700 ppm) and selectivity toward hydrogen at room temperature, as well as long-term stability over five months under ambient conditions. To gain further insight into the gas sensing mechanism over the surface, we employed a dedicated apparatus, namely operando diffuse reflectance infrared Fourier transform, by exposing the chemoresistive sensor to hydrogen gas under dry air conditions.
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AIM: To evaluate the impact of aldosterone excess on renal function in individuals with primary aldosteronism and to compare its evolution after surgery or mineralocorticoid receptor antagonist (MRA) treatment. METHODS: A multicentre, retrospective cohort study of primary aldosteronism patients in follow-up in 36 Spanish tertiary hospitals, who underwent specific treatment for primary aldosteronism (MRA or adrenalectomy). RESULTS: A total of 789 patients with primary aldosteronism were included, with a median age of 57.5âyears and 41.8% being women. At primary aldosteronism diagnosis, the prevalence of chronic kidney disease (CKD) was 10.7% ( n â=â84), with 75% of cases classified as state 3a ( n â=â63). Primary aldosteronism patients with CKD had a longer duration of hypertension, a higher prevalence of type 2 diabetes, dyslipidaemia, cardiovascular events, hypokalaemia, and albuminuria. Unilateral adrenalectomy was performed in 41.8% of cases ( n â=â330), and 459 patients were treated with MRA. After a median follow-up of 30.7âmonths (range 13.3-68.4), there was a significant decline in the estimated glomerular filtration rate (eGFR) in operated patients and those receiving MRA. During follow-up, 24.4% of patients with CKD at the time of primary aldosteronism diagnosis had normalized renal function, and 39% of those with albuminuria had albuminuria remission. There were no differences in renal function or albuminuria regression between the two therapy groups. However, development of albuminuria was less common in operated than in medically treated patients (0 vs. 6.0%, P â=â0.009). CONCLUSION: CKD affects around 10% of the patients with primary aldosteronism, with a higher risk in individuals with long-term hypertension, type 2 diabetes, dyslipidaemia, cardiovascular events, hypokalaemia, and albuminuria. At short-term, both MRA and surgical treatment lead to a reduction of renal function, but adrenalectomy led to higher renal protection.
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Adrenalectomía , Hiperaldosteronismo , Antagonistas de Receptores de Mineralocorticoides , Sistema de Registros , Humanos , Hiperaldosteronismo/complicaciones , Hiperaldosteronismo/fisiopatología , Femenino , Masculino , Persona de Mediana Edad , España/epidemiología , Estudios Retrospectivos , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico , Anciano , Riñón/fisiopatología , Insuficiencia Renal Crónica/fisiopatología , Insuficiencia Renal Crónica/complicaciones , Adulto , Tasa de Filtración Glomerular , Estudios de CohortesRESUMEN
Van Wyk-Grumbach syndrome (VWGS) refers to the development of peripheral precocious puberty, long-standing hypothyroidism, and gonadal masses; when not diagnosed, an unnecessary gonadectomy may be performed. Herein, we present a case of a 10-year-old girl with Down's syndrome, short stature, and vitiligo who presented to our hospital with vaginal bleeding and a palpable pelvic mass. Upon ultrasound and topographical examination, bilateral ovarian masses with negative tumor markers were detected. After bilateral gonadectomy, endocrine studies revealed profound hypothyroidism and peripheral puberty that led to the VWGS syndrome diagnosis (TSH 367.3 mUI/mL, isolated menstruation, indetectable LH, and elevated estradiol). Levothyroxine treatment improved obesity and short stature, and sexual hormone replacement began at 13 years of age. The literature on Van Wyk-Grumbach syndrome shows that it presents most often in women, and classic hypothyroidism symptoms always precede the diagnosis. Approximately 11% of patients have Down's syndrome, sometimes tumor markers are elevated, and some develop severe symptoms (myopathy, short stature, mental delay, ascites, pericardial effusion, Cullen's sign, pituitary hyperplasia, and severe anemia) that respond to levothyroxine treatment. Conclusions: Children with peripheral precocious puberty and gonadal masses must be studied for hypothyroidism before any radical decision is made.
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RNA sequencing is an approach to transcriptomic profiling that enables the detection of differentially expressed genes in response to genetic mutation or experimental treatment, among other uses. Here we describe a method for the use of a customizable, user-friendly bioinformatic pipeline to identify differentially expressed genes in RNA sequencing data obtained from C. elegans, with attention to the improvement in reproducibility and accuracy of results.
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Caenorhabditis elegans , Biología Computacional , Perfilación de la Expresión Génica , Análisis de Secuencia de ARN , Programas Informáticos , Flujo de Trabajo , Caenorhabditis elegans/genética , Animales , Biología Computacional/métodos , Análisis de Secuencia de ARN/métodos , Perfilación de la Expresión Génica/métodos , Transcriptoma , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Reproducibilidad de los ResultadosRESUMEN
BACKGROUND: Nursing care for older women represent a challenge worldwide due to its characteristics. When communication is impaired between primary care nurses and older women living alone, an imbalance in power relations occurs. The main objective of this study is to analyse the power relations between older women and primary care nurses in situations of active listening, shared decision-making and participation in care. METHODS: We developed a qualitative study in southern Spain using a discursive and gender approach. We used purposeful sampling to interview older women who lived alone and received home nursing care. Simultaneously, we conducted focus groups with primary care nurses who provided home care to older women. A linguistic analysis of the transcripts was carried out. RESULTS: Nine semi-structured face-to-face interviews were conducted with older women who lived alone and two face-to-face focus groups with four primary care nurses in each. The discourse of the participants demonstrated an imbalance in power relations. Influenced by work overload, active listening was considered a privilege in primary care nurses´ discourse. Regarding shared decision-making, older women´s discourses revealed "mirages" of real situations where they thought they were deciding. Participation in care was difficult since older women saw themselves as a nuisance in nurses´ presence, and primary care nurses did not facilitate older women's engagement. Older women weren´t considered when organising home visits and had interiorised a subordinated feeling. Similarly, a strict sense of identity made primary care nurses feel powerful in their relationships with older women. CONCLUSIONS: The discourse of older women represented them as victims of a hostile panorama whilst they were sometimes satisfied with the deficient care received. The discourse of primary care nurses used more discursive strategies to represent themselves as professionals committed to caring. However, it also revealed deficiencies in care, discriminatory elements, and feelings of being limited by their working conditions. Active listening to older women and engagement in decision-making readjust empower the older women. Attending to the needs and concerns of primary care nurses could recalibrate the power imbalance between them and healthcare organisations.
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BACKGROUND: Establishing adequate reference intervals (RIs) for vitamins A and E is essential for diagnosing and preventing deficiencies. Due to the current boom in data mining and its easy applicability, more laboratories are establishing RIs using indirect methods. Our study aims to obtain RIs using four indirect data-mining procedures (Bhattacharya, Hoffmann, Kosmic, and RefineR) for vitamins A and E. MATERIAL AND METHODS: 8943 individuals were collected to establish the RIs. After using different data cleaning steps and checking whether these data should be divided according to age and gender based on multiple linear regression and variance component analyses, indirect RIs were calculated using specific Excel spreadsheets or R-packages software. RESULTS: A total of 2004 records were eligible. For vitamin A, the RIs obtained were (1.11 - 2.68) µmol/L, (1.13 - 2.70) µmol/L, (1.13 - 2.71) µmol/L, and (1.17 - 2.66) µmol/L using the Bhattacharya, Hoffmann, Kosmic and RefineR approaches, respectively. For vitamin E, these intervals were (17.3 - 49.9) µmol/L (Bhattacharya), (17.3 - 48.9) µmol/L (Hoffmann), (19.6 - 50.3) µmol/L (Kosmic), and (19.4 - 50.9) µmol/L (RefineR). In all cases, the RIs were comparable. CONCLUSIONS: Suitable RIs for vitamins A and E were calculated using four indirect methods that are suitable and adapted to our population's demographic characteristics.
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Minería de Datos , Vitamina A , alfa-Tocoferol , Humanos , Vitamina A/sangre , alfa-Tocoferol/sangre , Masculino , Femenino , Adulto , Persona de Mediana Edad , Valores de Referencia , Adulto Joven , Adolescente , Anciano , Niño , Preescolar , Anciano de 80 o más AñosRESUMEN
AIM: To evaluate the influence on peri-implant crestal bone loss exerted by the vertical mucosal thickness and the abutment height over 12 months after placement of the restoration on subcrestal implants with change of platform, using a restoration abutment platform smaller than the implant platform. MATERIALS AND METHODS: A total of 99 implants were rehabilitated in the maxillary and mandibular posterior regions. A total of 22 implants were rehabilitated in the maxilla and 77 implants in the mandible, using digitally designed customized abutments with Atlantis weborder software, from the commercial house Dentsply Sirona (Dentsply Sirona S.A., Barcelona, Spain), version 4.6.5, adapting the height to the vertical thickness of the mucosa. Clinical and radiographic monitoring begins during the surgical procedure of placement of the implant and ends 12 months afterwards. Crestal bone loss was evaluated through the Carestream® CS8100 3D radiographic equipment. RESULTS: In all cases, the greatest loss of marginal bone occurred between the day of surgery (Tx) and placement of the rehabilitation (To). The average bone loss between both times was greater when the abutment height and vertical mucosal thickness did not exceed 3 mm. Subsequently, bone loss slowed and stabilized at 12 months. CONCLUSIONS: The minimum abutment height and the vertical mucosal thickness are factors to take into account when minimizing peri-implant marginal bone loss, the abutment height having the greatest importance according to the clinical data obtained.
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Pérdida de Hueso Alveolar , Pilares Dentales , Diseño de Implante Dental-Pilar , Humanos , Pérdida de Hueso Alveolar/etiología , Pérdida de Hueso Alveolar/diagnóstico por imagen , Estudios Prospectivos , Femenino , Masculino , Persona de Mediana Edad , Implantación Dental Endoósea/métodos , Mandíbula/cirugía , Mandíbula/diagnóstico por imagen , Implantes Dentales , Maxilar/cirugía , Maxilar/diagnóstico por imagen , Anciano , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/patología , AdultoRESUMEN
Enteral nutrition (EN) therapy in ICU patients requiring oxygen therapy with high-flow nasal cannula (HFNC) and/or noninvasive mechanical ventilation (NIMV) is controversial. A prospective, cohort, observational, and multicenter study was conducted in 10 ICUs in Spain to analyze the 90-day mortality, tolerance, side effects, and infectious complications of trophic EN in patients requiring HFNC therapy and/or NIVM. A total of 149 patients were enrolled. The mean age, severity scores, tracheobronchitis, bacteremia, and antimicrobial therapy were significantly higher in deceased than in living patients (p < 0.05), and the mortality rate was 14.8%. A total of 110 patients received oral trophic feedings, 36 patients received nasogastric tube feedings (NGFs), and 3 received mixed feedings. Trophic EN was discontinued in only ten (14.9%) patients because of feeding-related complications. The variables selected for the multivariate logistic regression on feeding discontinuation were SOFA upon admission (OR per unit = 1.461) and urea (OR per mg/dL = 1.029). There were no significant differences in the development of new infections according to the route of EN administration. Early trophic feeding administered to patients with acute respiratory failure requiring noninvasive ventilation is safe and feasible, and is associated with few dietary and infectious complications in a mortality, setting comparable to similar studies.
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Nutrición Enteral , Unidades de Cuidados Intensivos , Ventilación no Invasiva , Terapia por Inhalación de Oxígeno , Humanos , Masculino , Femenino , Persona de Mediana Edad , Estudios Prospectivos , Anciano , Ventilación no Invasiva/métodos , Nutrición Enteral/métodos , Terapia por Inhalación de Oxígeno/métodos , España , Insuficiencia Respiratoria/terapia , Insuficiencia Respiratoria/mortalidad , Resultado del Tratamiento , Respiración Artificial , Modelos LogísticosRESUMEN
BACKGROUND: Approximately 30% of patients presenting with acute ischemic stroke (AIS) due to large vessel occlusion have pre-stroke modified Rankin Scale (mRS) scores ≥2. We aimed to investigate the safety and outcomes of endovascular treatment (EVT) in patients with AIS with moderate pre-stroke disability (mRS score 3) in an extended time frame (ie, 6-24 hours from the last time known well). METHODS: Data were collected from five centers in Europe and the USA from January 2018 to January 2023 and included 180 patients who underwent EVT in an extended time frame. Patients were divided into two groups of 90 each (Group 1: pre-mRS 0-2; Group 2: pre-mRS 3; 71% women, mean age 80.3±11.9 years). Primary outcomes were: (1) 3-month good clinical outcome (Group 1: mRS 0-2, Group 2: mRS 0-3) and ΔmRS; (2) any hemorrhagic transformation (HT); and (3) symptomatic HT. Secondary outcomes were successful and complete recanalization after EVT and 3-month mortality. RESULTS: No between-group differences were found in the 3-month good clinical outcome (26.6% vs 25.5%, P=0.974), any HT (26.6% vs 22%, P=0.733), and symptomatic HT (8.9 vs 4.4%, P=0.232). Unexpectedly, ΔmRS was significantly smaller in Group 2 compared with Group 1 (1.64±1.61 vs 2.97±1.69, P<0.001). No between-group differences were found in secondary outcomes. CONCLUSION: Patients with pre-stroke mRS 3 are likely to have similar outcomes after EVT in the extended time frame to those with pre-stroke mRS 0-2, with no difference in safety.
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This study evaluates the efficacy of hyperspectral data for detecting yellow and brown rust in wheat, employing machine learning models and the SMOTE (Synthetic Minority Oversampling Technique) augmentation technique to tackle unbalanced datasets. Artificial Neural Network (ANN), Support Vector Machine (SVM), Random Forest (RF), and Gaussian Naïve Bayes (GNB) models were assessed. Overall, SVM and RF models showed higher accuracies, particularly when utilizing SMOTE-enhanced datasets. The RF model achieved 70% accuracy in detecting yellow rust without data alteration. Conversely, for brown rust, the SVM model outperformed others, reaching 63% accuracy with SMOTE applied to the training set. This study highlights the potential of spectral data and machine learning (ML) techniques in plant disease detection. It emphasizes the need for further research in data processing methodologies, particularly in exploring the impact of techniques like SMOTE on model performance.
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INTRODUCTION: Urine free cortisol measurements are routinely performed to evaluate hypercortisolism. Despite their analytical inaccuracy, immunoassay-based methods are frequently used. Advances in liquid chromatography-high-resolution mass spectrometry (LC-HRMS) facilitate the incorporation of powerful diagnostic tools into clinical laboratories. In addition to its high analytical specificity and simultaneous analysis of different metabolites, accurate mass measurement allows for untargeted compound identification, which may help to identify clinically relevant metabolites or drugs. METHODS: The present study aimed to validate a simple routine LC-HRMS method to quantify cortisol, cortisone, 6ß-hydroxycortisol, and 18-hydroxycortisol simultaneously in human urine. Additionally, the study also validated a GC-MS method for the same steroids, evaluated their cross-reactivity with commercial cortisol immunoassays, and quantified the 24 h urine excretion in patients under clinical suspicion or follow-up for hypercortisolism. RESULTS: The LC-HRMS method involved liquid-liquid extraction using dichloromethane, micro-LC for chromatographic separation and detection using the accurate masses of the steroids, and simultaneous high-resolution full scan acquisition. The method presented acceptable linearity, precision, and accuracy. Significant interference from 6ß-hydroxycortisol and cortisone was demonstrated in the cortisol immunoassays, which impacted their reliability in the follow-up of patients with hypercortisolism and significant changes in these cortisol metabolites (i.e., due to drug-induced changes in CYP3A4 activity). CONCLUSION: A rapid and accurate routine LC-HRMS method was validated, which is useful for the evaluation of hypercortisolism and other disorders of glucocorticoid and mineralocorticoid metabolism.
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Cortisona , Cromatografía de Gases y Espectrometría de Masas , Hidrocortisona , Humanos , Hidrocortisona/orina , Hidrocortisona/análogos & derivados , Cortisona/orina , Cromatografía de Gases y Espectrometría de Masas/métodos , Cromatografía Liquida/métodos , Glucocorticoides/orina , Síndrome de Cushing/orina , Síndrome de Cushing/diagnóstico , Masculino , FemeninoRESUMEN
En fechas recientes, el Secretario General de Naciones Unidas, António Guterres, presentaba una nota técnica sobre ciencias del comportamiento (United Nations, 2021) y su aplicación por parte de distintas organizaciones de Naciones Unidas, para lograr cubrir los Objetivos de Desarrollo Sostenibles 2030. Asimismo, otras organizaciones de ámbito supranacional están también creando o bien unidades propias de «análisis y diseño del comportamiento» o bien liderando iniciativas específicas. Hasta la fecha, no se ha analizado la estructura de este tipo de unidades. El objetivo de nuestro trabajo es conocer, a través de un estudio observacional de sus sitios web, tanto la estructura de las unidades de análisis de determinantes del comportamiento de organizaciones supranacionales como su composición, así como los principales tipos de proyectos que llevan a cabo y las implicaciones y oportunidades que representan para los profesionales de la psicología.(AU)
Recently, the United Nations Secretary-General, António Guterres, presented a technical note on behavioral science (United Nations, 2021) and its application by different UN organizations, in order to achieve the 2030 Sustainable Development Goals. Other supranational organizations are also setting up their own «behavioral analysis and design units» or leading specific initiatives. So far, the structure of such behavioral analysis units has not been examined. The aim of our work is to find out, through an observational study of their websites, both the structure and composition of the behavior design and analysis units of supranational organizations, as well as the main types of projects they carry out and the opportunities and implications created for psychology professionals.(AU)
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Humanos , Masculino , Femenino , Organizaciones , Conducta , Análisis Aplicado de la Conducta , PsicologíaRESUMEN
Despite the technological importance of semiconductor black phosphorus (BP) in materials science, maintaining the stability of BP crystals in organic media and protecting them from environmental oxidation remains challenging. In this study, we present the synthesis of bulk BP and the exploitation of the viscoelastic properties of a regenerated silk fibroin (SF) film as a biocompatible substrate to transfer BP flakes, thereby preventing oxidation. A model based on the flow of polymers revealed that the applied flow-induced stresses exceed the yield stress of the BP aggregate. Raman spectroscopy was used to investigate the exfoliation efficiency as well as the environmental stability of BP transferred on the SF substrate. Notably, BP flakes transferred to the SF substrate demonstrated improved stability when SF was dissolved in a phosphate-buffered saline medium, and in vitro cancer cell viability experiments demonstrate the tumor ablation efficiency under visible to near-infrared (Vis-nIR) radiation. Moreover, the SF and BP-enriched SF (SF/BP) solution was shown to be processable via extrusion-based three-dimensional (3D) printing. Therefore, this work paves the way for a general method for the transferring of BP on natural biodegradable polymers and processing them via 3D printing toward novel functionalities and complex shapes for biomedical purposes.
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RNA helicase DHX15 plays a significant role in vasculature development and lung metastasis in vertebrates. In addition, several studies have demonstrated the overexpression of DHX15 in the context of hepatocellular carcinoma. Therefore, we hypothesized that this helicase may play a significant role in liver regeneration, physiology, and pathology. Dhx15 gene deficiency was generated by CRISPR/Cas9 in zebrafish and by TALEN-RNA in mice. AUM Antisense-Oligonucleotides were used to silence Dhx15 in wild-type mice. The hepatocellular carcinoma tumor induction model was generated by subcutaneous injection of Hepa 1-6 cells. Homozygous Dhx15 gene deficiency was lethal in zebrafish and mouse embryos. Dhx15 gene deficiency impaired liver organogenesis in zebrafish embryos and liver regeneration after partial hepatectomy in mice. Also, heterozygous mice presented decreased number and size of liver metastasis after Hepa 1-6 cells injection compared to wild-type mice. Dhx15 gene silencing with AUM Antisense-Oligonucleotides in wild-type mice resulted in 80% reduced expression in the liver and a significant reduction in other major organs. In addition, Dhx15 gene silencing significantly hindered primary tumor growth in the hepatocellular carcinoma experimental model. Regarding the potential use of DHX15 as a diagnostic marker for liver disease, patients with hepatocellular carcinoma showed increased levels of DHX15 in blood samples compared with subjects without hepatic affectation. In conclusion, Dhx15 is a key regulator of liver physiology and organogenesis, is increased in the blood of cirrhotic and hepatocellular carcinoma patients, and plays a key role in controlling hepatocellular carcinoma tumor growth and expansion in experimental models.
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Carcinoma Hepatocelular , ARN Helicasas , Proteínas de Pez Cebra , Pez Cebra , Animales , Humanos , Ratones , Carcinoma Hepatocelular/genética , Oligonucleótidos , ARN Helicasas/genética , Pez Cebra/genética , Proteínas de Pez Cebra/genéticaRESUMEN
The covalent bonding framework of crystalline single-bonded cubic AsN, recently synthesized under high pressure and high temperature conditions in a laser-heated diamond anvil cell, is here studied by means of density functional theory calculations and compared to single crystal X-ray diffraction data. The precise localization of the nonbonding electron lone pairs and the determination of their distances and orientations are related to the presence of characteristic structural motifs and space regions of the unit cell dominated by repulsive electronic interactions, with the relative orientation of the electron lone pairs playing a key role in minimizing the energy of the structure. We find that the vibrational modes associated with the expression of the lone pairs are strongly localized, an observation that may have implications for the thermal conductivity of the compound. The results indicate the thermodynamic stability of the experimentally observed structure of AsN above â¼17 GPa, provide a detailed insight into the nature of the chemical bonding network underlying the formation of this compound, and open new perspectives to the design and high pressure synthesis of new pnictogen-based advanced materials for potential applications of energetic and technological relevance.
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Hexagonal boron nitride (hBN) and black phosphorus (bP) are crystalline materials that can be seen as ordered stackings of two-dimensional layers, which lead to outstanding anisotropic physical properties. Knowledge of the thermal equations of state of hBN and bP is of great interest in the field of 2D materials for a better understanding of their anisotropic thermo-mechanical properties and exfoliation mechanism towards the preparation of important single-layer materials like hexagonal boron nitride nanosheets and phosphorene. Despite several theoretical and experimental studies, important uncertainties remain in the determination of the thermoelastic parameters of hBN and bP. Here, we report accurate thermal expansion and compressibility measurements along the individual crystallographic axes, using in situ high-temperature and high-pressure high-resolution synchrotron X-ray diffraction. In particular, we have quantitatively determined the subtle variations of the in-plane and volumetric thermal expansion coefficients and compressibility parameters by subjecting these materials to hydrostatic conditions and by collecting a large number of data points in small pressure and temperature increments. In addition, based on the anisotropic behavior of bP, we propose the use of this material as a sensor for the simultaneous determination of pressure and temperature in the range of 0-5 GPa and 298-1700 K, respectively.
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BACKGROUND & AIMS: The management of acute kidney injury (AKI) in cirrhosis is challenging. The EASL guidelines proposed an algorithm for the management of AKI, but this has never been validated. We aimed to prospectively evaluate this algorithm in clinical practice. METHODS: We performed a prospective cohort study in consecutive hospitalized patients with cirrhosis and AKI. The EASL management algorithm includes identification/treatment of precipitating factors, 2-day albumin infusion in patients with AKI ≥stage 1B, and treatment with terlipressin in patients with hepatorenal syndrome (HRS-AKI). The primary outcome was treatment response, which included both full and partial response. Secondary outcomes were survival and adverse events associated with terlipressin therapy. RESULTS: A total of 202 AKI episodes in 139 patients were included. Overall treatment response was 80%, while renal replacement therapy was required in only 8%. Response to albumin infusion was achieved in one-third of episodes. Of patients not responding to albumin, most (74%) did not meet the diagnostic criteria of HRS-AKI, with acute tubular necrosis (ATN) being the most common phenotype. The response rate in patients not meeting the criteria for HRS-AKI was 70%. Only 30 patients met the diagnostic criteria for HRS-AKI, and their response rate to terlipressin was 61%. Median time from AKI diagnosis to terlipressin initiation was only 2.5 days. While uNGAL (urinary neutrophil gelatinase-associated lipocalin) could differentiate ATN from other phenotypes (AUROC 0.78), it did not predict response to therapy in HRS-AKI. Ninety-day transplant-free survival was negatively associated with MELD-Na, ATN and HRS-AKI as well as uNGAL. Three patients treated with terlipressin developed pulmonary edema. CONCLUSIONS: The application of the EASL AKI algorithm is associated with very good response rates and does not significantly delay initiation of terlipressin therapy. IMPACT AND IMPLICATIONS: The occurrence of acute kidney injury (AKI) in patients with cirrhosis is associated with poor short-term mortality. Improving its rapid identification and prompt management was the focus of the recently proposed EASL AKI algorithm. This is the first prospective study demonstrating that high AKI response rates are achieved with the use of this algorithm, which includes identification of AKI, treatment of precipitating factors, a 2-day albumin challenge in patients with AKI ≥1B, and supportive therapy in patients with persistent AKI not meeting HRS-AKI criteria or terlipressin with albumin in those with HRS-AKI. These findings support the use of this algorithm in clinical practice.
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Lesión Renal Aguda , Algoritmos , Cirrosis Hepática , Terlipresina , Humanos , Lesión Renal Aguda/etiología , Lesión Renal Aguda/diagnóstico , Masculino , Femenino , Estudios Prospectivos , Persona de Mediana Edad , Cirrosis Hepática/complicaciones , Terlipresina/administración & dosificación , Anciano , Albúminas/administración & dosificación , Vasoconstrictores/administración & dosificación , Vasoconstrictores/uso terapéutico , Lipresina/análogos & derivados , Lipresina/administración & dosificación , Lipresina/uso terapéutico , Resultado del Tratamiento , Síndrome Hepatorrenal/etiología , Síndrome Hepatorrenal/diagnóstico , Síndrome Hepatorrenal/tratamiento farmacológico , Guías de Práctica Clínica como AsuntoRESUMEN
Purpose: To compare the clinical and hormonal characteristics of patients with familial hyperaldosteronism (FH) and sporadic primary aldosteronism (PA). Methods: A systematic review of the literature was performed for the identification of FH patients. The SPAIN-ALDO registry cohort of patients with no suspicion of FH was chosen as the comparator group (sporadic group). Results: A total of 360 FH (246 FH type I, 73 type II, 29 type III, and 12 type IV) cases and 830 sporadic PA patients were included. Patients with FH-I were younger than sporadic cases, and women were more commonly affected (P = 0.003). In addition, the plasma aldosterone concentration (PAC) was lower, plasma renin activity (PRA) higher, and hypokalemia (P < 0.001) less frequent than in sporadic cases. Except for a younger age (P < 0.001) and higher diastolic blood pressure (P = 0.006), the clinical and hormonal profiles of FH-II and sporadic cases were similar. FH-III had a distinct phenotype, with higher PAC and higher frequency of hypokalemia (P < 0.001), and presented 45 years before sporadic cases. Nevertheless, the clinical and hormonal phenotypes of FH-IV and sporadic cases were similar, with the former being younger and having lower serum potassium levels. Conclusion: In addition to being younger and having a family history of PA, FH-I and III share other typical characteristics. In this regard, FH-I is characterized by a low prevalence of hypokalemia and FH-III by a severe aldosterone excess causing hypokalemia in more than 85% of patients. The clinical and hormonal phenotype of type II and IV is similar to the sporadic cases.