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1.
Mol Cell ; 76(4): 531-545.e5, 2019 11 21.
Artículo en Inglés | MEDLINE | ID: mdl-31706703

RESUMEN

The glucocorticoid receptor (GR) is a potent metabolic regulator and a major drug target. While GR is known to play integral roles in circadian biology, its rhythmic genomic actions have never been characterized. Here we mapped GR's chromatin occupancy in mouse livers throughout the day and night cycle. We show how GR partitions metabolic processes by time-dependent target gene regulation and controls circulating glucose and triglycerides differentially during feeding and fasting. Highlighting the dominant role GR plays in synchronizing circadian amplitudes, we find that the majority of oscillating genes are bound by and depend on GR. This rhythmic pattern is altered by high-fat diet in a ligand-independent manner. We find that the remodeling of oscillatory gene expression and postprandial GR binding results from a concomitant increase of STAT5 co-occupancy in obese mice. Altogether, our findings highlight GR's fundamental role in the rhythmic orchestration of hepatic metabolism.


Asunto(s)
Cromatina/metabolismo , Relojes Circadianos , Ritmo Circadiano , Dieta Alta en Grasa , Grasas de la Dieta/metabolismo , Metabolismo Energético , Hígado/metabolismo , Obesidad/metabolismo , Receptores de Glucocorticoides/metabolismo , Animales , Glucemia/metabolismo , Relojes Circadianos/genética , Ritmo Circadiano/genética , Grasas de la Dieta/administración & dosificación , Grasas de la Dieta/sangre , Modelos Animales de Enfermedad , Metabolismo Energético/genética , Ayuno/metabolismo , Regulación de la Expresión Génica , Glucocorticoides/metabolismo , Gluconeogénesis , Ligandos , Masculino , Ratones Endogámicos C57BL , Ratones Noqueados , Obesidad/sangre , Obesidad/genética , PPAR alfa/genética , PPAR alfa/metabolismo , Periodo Posprandial , Receptores de Glucocorticoides/deficiencia , Receptores de Glucocorticoides/genética , Factor de Transcripción STAT5/genética , Factor de Transcripción STAT5/metabolismo , Vías Secretoras , Transducción de Señal , Factores de Tiempo , Transcripción Genética , Triglicéridos/sangre
2.
Clin Chem ; 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38712647

RESUMEN

BACKGROUND: Vitamin D, acknowledged since the 1930s for its role in preventing rickets, gained additional prominence in relation to fragility fracture prevention in the late 1980s. From the early 2000s, connections between vitamin D deficiency and extra-skeletal pathologies emerged, alongside increased awareness of widespread deficits. This prompted crucial debates on optimal serum concentrations, expected to conclude when the outcomes of high-dose supplementation randomized controlled trials were available. Skepticism arose with inconclusive results from these trials. CONTENT: This review begins with an exploration of vitamin D metabolism, followed by a detailed description of the measurement of vitamin D metabolites and the crucial role of standardization. Subsequent sections focus on the association of vitamin D with bone health and explore the extra-skeletal effects. The review concludes with a comprehensive discussion on the definition of vitamin D status and its implications for supplementation. SUMMARY: Despite standardization efforts, assay variations and challenges still exist, especially in specific patient groups. Vitamin D supplementation has a significant impact on bone metabolism and optimal vitamin D status improves the efficacy of antiresorptive drugs such as bisphosphonates. The extra-skeletal effects of vitamin D remain debated, but may include potential benefits in conditions such as respiratory infections and cancer mortality, particularly in deficient individuals. The definition of vitamin D sufficiency is nuanced, especially when variations in population groups and analytical methods are taken into account. Despite ongoing debates and recent mega-trials tempering enthusiasm, vitamin D remains a complex and essential element in human health. Further research is needed to clarify its role in various health outcomes and guide supplementation strategies.

3.
Clin Chem Lab Med ; 62(2): 253-261, 2024 Jan 26.
Artículo en Inglés | MEDLINE | ID: mdl-37773773

RESUMEN

OBJECTIVES: Chronic kidney disease (CKD) is a global health issue, ranking as the third leading cause of death worldwide. CKD diagnosis and management depend on clinical laboratory tests, necessitating consistency for precise patient care. Global harmonization of CKD testing through clinical practice guidelines (CPGs) is recommended. Prior to CPG development, assessing the current CKD testing landscape is crucial. In 2022, the European Federation of Laboratory Medicine (EFLM) conducted an online survey among European laboratories associated with EFLM, evaluating CKD testing practices, including new glomerular filtration rate (GFR) estimation methods. This report summarizes the 2022 survey findings and offers recommendations for improving CKD test standardization. METHODS: An online survey was conducted in November 2022 using a questionnaire hosted on LimeSurvey sent to European laboratories affiliated with the EFLM. The survey results were recorded in Excel files and analysed. RESULTS: The results highlight significant discrepancies among countries in unit expression, methods, cystatin C use, and GFR calculation equations. Additionally, limited attention to pediatric renal biology specifics, varied proteinuria and albuminuria result expressions, and limited awareness of GFR measurement methods through iohexol clearance are noted. CONCLUSIONS: In an effort to enhance the standardization of crucial biomarkers utilized in nephrology for evaluating renal function and diagnosing kidney injuries, the EFLM Task Group on CKD suggests nine practical recommendations tailored for European laboratories. The group is confident that implementing these measures will minimize result expression discrepancies, ultimately leading to enhanced patient care.


Asunto(s)
Laboratorios , Insuficiencia Renal Crónica , Humanos , Niño , Pruebas de Función Renal/métodos , Tasa de Filtración Glomerular , Biomarcadores , Encuestas y Cuestionarios , Insuficiencia Renal Crónica/diagnóstico , Creatinina/metabolismo
4.
Environ Res ; 252(Pt 1): 118710, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38493848

RESUMEN

Organic food consumption in children has been shown to reduce the body burden of chemical pesticides. However, there is little evidence of human health benefits associated with the consumption of organic foods. The objectives were to i) determine the effectiveness of an organic food intervention treatment in reducing the magnitude of an inflammation biomarker (C-reactive protein, CRP) in children (10-12 years) and ii) assess the association between the urinary biomarkers of exposure to pesticides and CRP. This work was part of the ORGANIKO cluster-randomized cross-over trial entailing a 40-day organic food treatment in healthy children. Urinary biomarkers of exposure to pesticides and inflammation (CRP) were measured using tandem mass spectrometry and ELISA immunoassay, respectively. Linear mixed-effect regression models of CRP were used to account for the effect and duration of organic food treatment. Multiple comparisons were handled using Benjamini-Hochberg correction. Results supported an anti-inflammatory effect of organic food treatment in children, albeit with mixed results, depending on the creatinine adjustment method; biomarker levels were divided by urinary creatinine (method a1), or urinary creatinine was used as a fixed effect variable (a2). In the a1 method, a time-dependent reduction for creatinine-adjusted CRP (ß = -0.019; 95% CI: -0.031, -0.006; q = 0.045) was observed during the organic food intervention period. A statistically significant association (ß = 0.104; 95% CI: 0.035, 0.173; q = 0.045) was found between the biomarker of pyrethroids exposure (3-PBA) and CRP inflammatory biomarker, but not for 6-CN. In the a2 method, similar trend of time-dependent reduction for creatinine-adjusted CRP (ß = -0.008; 95% CI: -0.021, 0.004; p = 0.197) was observed during the organic food intervention period, but did not reach statistical significance (q > 0.05); the associations of pyrethroid and neonicotinoid biomarkers with CRP were not statistically significant (q > 0.05). More studies are warranted to sufficiently understand the potential anti-inflammatory response of an organic food treatment.


Asunto(s)
Biomarcadores , Proteína C-Reactiva , Estudios Cruzados , Alimentos Orgánicos , Plaguicidas , Humanos , Niño , Masculino , Femenino , Proteína C-Reactiva/análisis , Biomarcadores/orina , Plaguicidas/orina , Inflamación/orina , Exposición a Riesgos Ambientales/análisis
5.
Opt Express ; 31(17): 27582-27593, 2023 Aug 14.
Artículo en Inglés | MEDLINE | ID: mdl-37710830

RESUMEN

We demonstrate that by seeding an accelerating ring-Airy beam with a finite number of off-axis optical vortices, it transforms into a tornado wave (ToW) upon propagation. Using numerical simulations, we show that both the spiraling high-intensity lobes and the optical vortices exhibit angular acceleration and follow interwinding braid-like trajectories. Likewise, we study the effect of the number, position, and topological charge of the vortices on the propagation dynamics and reveal the connection between optical vortices and optical tornados.

6.
Opt Lett ; 48(8): 2206-2209, 2023 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-37058678

RESUMEN

We investigate the statistical mechanics of the photonic Ablowitz-Ladik lattice, the integrable version of the discrete nonlinear Schrödinger equation. In this regard, we demonstrate that in the presence of perturbations, the complex response of this system can be accurately captured within the framework of optical thermodynamics. Along these lines, we shed light on the true relevance of chaos in the thermalization of the Ablowitz-Ladik system. Our results indicate that when linear and nonlinear perturbations are incorporated, this weakly nonlinear lattice will thermalize into a proper Rayleigh-Jeans distribution with a well-defined temperature and chemical potential, in spite of the fact that the underlying nonlinearity is non-local and hence does not have a multi-wave mixing representation. This result illustrates that in the supermode basis, a non-local and non-Hermitian nonlinearity can in fact properly thermalize this periodic array in the presence of two quasi-conserved quantities.

7.
Calcif Tissue Int ; 112(2): 233-242, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36571614

RESUMEN

Alkaline phosphatases (ALPs) are a group of isoenzymes, situated on the external layer of the cell membrane; they catalyze the hydrolysis of organic phosphate esters present in the extracellular space. Zinc and magnesium are significant co-factors for the biological activity of these enzymes. Although ALPs are available in various body tissues and have distinct physiochemical properties, they are true isoenzymes since they catalyze a similar reaction. In the liver, ALP is cytosolic and present in the canalicular membrane of the hepatocytes. ALPs are available in placenta, ileal mucosa, kidney, bone, and liver. However, most of the ALPs in serum (over 80%) are delivered from liver and bone and in more modest quantities from the intestines. Despite the fact that alkaline phosphatases are found in numerous tissues all through the body, their exact physiological function remains largely unknown.


Asunto(s)
Fosfatasa Alcalina , Isoenzimas , Embarazo , Femenino , Humanos , Isoenzimas/metabolismo , Placenta/metabolismo , Huesos/metabolismo , Intestinos , Hígado/metabolismo
8.
Clin Chem Lab Med ; 61(9): 1561-1566, 2023 08 28.
Artículo en Inglés | MEDLINE | ID: mdl-36995129

RESUMEN

OBJECTIVES: The exploration of the metabolites in the degradation pathways of vitamin D (VTD) has gained importance in recent years and simultaneous quantitation of twenty-five-hydroxy vitamin D (25(OH)D) mass concentration together with 24,25-dihydroxyvitamin D (24,25(OH)2D) has been proposed as a newer approach to define VTD deficiency. Yet, no data are available on 24,25(OH)2D biological variation (BV). In this study, we evaluated 24,25(OH)2D's BV on the European Biological Variation Study (EuBIVAS) cohort samples to determine if analytical performance specifications (APS) for 24,25(OH)2D could be generated. METHODS: Six European laboratories recruited 91 healthy participants. 25(OH)D and 24,25(OH)2D concentrations in K3-EDTA plasma were examined weekly for up to 10 weeks in duplicate with a validated LC-MS/MS method. The Vitamin D Metabolite Ratio (24,25(OH)2D divided by 25(OH)D × 100) was also calculated at each time point. RESULTS: Linear regression of the mean 24,25(OH)2D concentrations at each blood collection showed participants were not in steady state. Variations of 24,25(OH)2D over time were significantly positively associated with the slopes of 25(OH)D concentrations over time and the concentration of 25(OH)D of the participant at inclusion, and negatively associated with body mass index (BMI), but not with age, gender, or location of the participant. The variation of the 24,25(OH)2D concentration in participants over a 10 weeks period was 34.6%. Methods that would detect a significant change linked to the natural production of 24,25(OH)2D over this period at p<0.05 would need a relative measurement uncertainty (u%)<14.9% while at p<0.01, relative measurement uncertainty should be <10.5%. CONCLUSIONS: We have defined for the first time APS for 24,25(OH)2D examinations. According to the growing interest in this metabolite, several laboratories and manufacturers might aim to develop specific methods for its determination. The results presented in this paper are thus necessary prerequisites for the validation of such methods.


Asunto(s)
Espectrometría de Masas en Tándem , Deficiencia de Vitamina D , Humanos , Cromatografía Liquida/métodos , Incertidumbre , Espectrometría de Masas en Tándem/métodos , Vitamina D , Deficiencia de Vitamina D/diagnóstico , Vitaminas
9.
Environ Res ; 216(Pt 3): 114675, 2023 01 01.
Artículo en Inglés | MEDLINE | ID: mdl-36367505

RESUMEN

BACKGROUND: Food contaminants, such as, pesticides and metals are ubiquitous in the food chain. Studies routinely report on the metals content of organic and conventional food crops. However, comparative human studies on the body burden of metals associated with organic food consumption are currently lacking. OBJECTIVES: The objectives were to i) determine the effectiveness of an organic food intervention in reducing the body burden of urinary concentration of lead (Pb) and cadmium (Cd) and ii) evaluate the association between metal exposures and biomarkers of oxidative damage in primary school children in Cyprus. METHODS: This study was part of the ORGANIKO cluster-randomized crossover trial, a 40-day organic food treatment to 149 healthy children (10-12 years) in Cyprus. Urinary biomarkers of Pb and Cd were determined using inductively coupled plasma mass spectrometry. Linear mixed-effect regression models were used to account for the effect and duration of the organic food treatment. Multiple comparisons were handled using Benjamini-Hochberg correction. RESULTS: A time-dependent reduction for creatinine-adjusted Pb during the intervention period was observed (ß = -0.021; 95% CI: -0.034, -0.008; p-adjusted = 0.01). A similar trend was observed for creatinine-adjusted Cd, but it was not significant (ß = -0.013; 95% CI: -0.026, 0.000; p-adjusted = 0.15). The creatinine-adjusted oxidative damage biomarkers were significantly associated with both metal biomarkers; Pb (8-OHdG: ß = 0.388, 95% CI: 0.303, 0.472; p-adjusted<0.001; MDA: ß = 0.187, 95% CI: 0.109, 0.265; p-adjusted<0.001; 8-iso-PGF2a: ß = 0.320, 95% CI: 0.244, 0.397; p-adjusted<0.001), and Cd (8-OHdG: ß = 0.148, 95% CI: 0.063, 0.233; p-adjusted = 0.003; MDA: ß = 0.107, 95% CI: 0.030, 0.184; p-adjusted = 0.018; 8-iso-PGF2a: ß = 0.263, 95% CI: 0.186, 0.339; p-adjusted<0.001). DISCUSSION: A 40-day organic food treatment reduced primary school children's exposures to Pb over time. More human studies in settings with high food contaminant profiles across common crops are warranted.


Asunto(s)
Cadmio , Plomo , Niño , Humanos , Cadmio/análisis , Plomo/análisis , Alimentos Orgánicos/análisis , Exposición a Riesgos Ambientales/análisis , Estudios Cruzados , Creatinina , Chipre , Biomarcadores/análisis , Instituciones Académicas
10.
Environ Res ; 238(Pt 1): 117001, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-37683788

RESUMEN

During recent years, we are moving away from the 'one exposure, one disease'-approach in occupational settings and towards a more comprehensive approach, taking into account the totality of exposures during a life course by using an exposome approach. Taking an exposome approach however is accompanied by many challenges, one of which, for example, relates to the collection of biological samples. Methods used for sample collection in occupational exposome studies should ideally be minimally invasive, while at the same time sensitive, and enable meaningful repeated sampling in a large population and over a longer time period. This might be hampered in specific situations e.g., people working in remote areas, during pandemics or with flexible work hours. In these situations, using self-sampling techniques might offer a solution. Therefore, our aim was to identify existing self-sampling techniques and to evaluate the applicability of these techniques in an occupational exposome context by conducting a literature review. We here present an overview of current self-sampling methodologies used to characterize the internal exposome. In addition, the use of different biological matrices was evaluated and subdivided based on their level of invasiveness and applicability in an occupational exposome context. In conclusion, this review and the overview of self-sampling techniques presented herein can serve as a guide in the design of future (occupational) exposome studies while circumventing sample collection challenges associated with exposome studies.


Asunto(s)
Exposoma , Humanos , Exposición a Riesgos Ambientales
11.
Bioessays ; 43(11): e2100159, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-34585760

RESUMEN

A paradigm shift in the human chronotoxicity of xenobiotics would study two-sided desynchronized phenomena of interfacial interactions between cyclic or periodic environmental insults and the endogenous response and recovery profile. These systems-based networks are under the influence of well-synchronized biological clocks and their metabolic regulators. This perspective argues in favor of addressing the concept of synchronization in studies involving critical life windows of susceptibility, or circadian rhythms, or 24-hour (periodic) diurnal rhythms and answering whether these disruptions in synchronization would affect response and recovery or disease phenotypes associated with environmental insults, e.g., xenobiotics. Synchronization or synchrony is defined as the totality of elements that appear during the same time period within a system, including the network of interactions between the system's elements. Desynchronized interfaces during critical life windows or in time-repeated exposure events would likely lead to initiating a cascade of adverse health effects associated with differentiated disease phenotypes.


Asunto(s)
Relojes Circadianos , Ritmo Circadiano , Humanos , Fenotipo , Tiempo , Xenobióticos/toxicidad
12.
Int J Neurosci ; 133(6): 612-620, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-34228947

RESUMEN

BACKGROUND: Evidence suggests that fluctuations of cortisol and physiological parameters can emerge during the course of mild Traumatic Brain Injury (mTBI). OBJECTIVE: To investigate fluctuations of cortisol and physiological parametersduring the acute phase of mTBI in hospitalized patients. METHODS: 30 participants (19 patients with mTBI and 11 controls) were examined for saliva cortisol dynamics, heart rate (HR), systolic arterial pressure (SAP), diastolic arterial pressure (DAP), mean arterial pressure (MAP) and body temperature (BT) fluctuations for four consecutive days. Also, the participants completed the Athens Insomnia Scale and Epworth Sleepiness Scales, in order to check for sleep problems. RESULTS: Patients showed elevated levels of cortisol relative to controls (peak at 8 am and lowest levels at 12 am), as well as for most physiological parameters. MAP was significantly higher for patients throughout the measurement period, and BT was elevated for patients relative to controls at almost all measurements of the first and second day. Mean HR tended to track at non-significantly higher levels for the mTBI group. Patients' sleepiness and insomnia values (ESS and AIS) were initially significantly higher relative to controls but the difference dissipated by day 4. CONCLUSION: The increase in absolute values of cortisol and physiological parameters measurements, indicates that in the acute phase of mTBI, a stressful process is activated which may affect sleep quality as well.Supplemental data for this article is available online at at doi: 10.1080/00207454.2021.1951264.


Asunto(s)
Conmoción Encefálica , Lesiones Encefálicas , Trastornos del Inicio y del Mantenimiento del Sueño , Humanos , Hidrocortisona , Saliva , Somnolencia
13.
Int J Mol Sci ; 24(9)2023 Apr 27.
Artículo en Inglés | MEDLINE | ID: mdl-37175668

RESUMEN

ETS2 repressor factor (ERF) insufficiency causes craniosynostosis (CRS4) in humans and mice. ERF is an ETS domain transcriptional repressor regulated by Erk1/2 phosphorylation via nucleo-cytoplasmic shuttling. Here, we analyze the onset and development of the craniosynostosis phenotype in an Erf-insufficient mouse model and evaluate the potential of the residual Erf activity augmented by pharmacological compounds to ameliorate the disease. Erf insufficiency appears to cause an initially compromised frontal bone formation and subsequent multisuture synostosis, reflecting distinct roles of Erf on the cells that give rise to skull and facial bones. We treated animals with Mek1/2 and nuclear export inhibitors, U0126 and KPT-330, respectively, to increase Erf activity by two independent pathways. We implemented both a low dosage locally over the calvaria and a systemic drug administration scheme to evaluate the possible indirect effects from other systems and minimize toxicity. The treatment of mice with either the inhibitors or the administration scheme alleviated the synostosis phenotype with minimal adverse effects. Our data suggest that the ERF level is an important regulator of cranial bone development and that pharmacological modulation of its activity may represent a valid intervention approach both in CRS4 and in other syndromic forms of craniosynostosis mediated by the FGFR-RAS-ERK-ERF pathway.


Asunto(s)
Craneosinostosis , Factores de Transcripción , Animales , Ratones , Craneosinostosis/tratamiento farmacológico , Craneosinostosis/genética , Sistema de Señalización de MAP Quinasas , Fosforilación , Proteínas Represoras , Cráneo
14.
Water Sci Technol ; 88(7): 1833-1846, 2023 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-37830999

RESUMEN

Illicit connections of wastewater to stormwater systems are the main drawback of separate sewer systems, as they lead to a direct discharge of untreated wastewater to the aquatic environment. Consequently, several inspection methods have been developed for detecting illicit connections. This study simultaneously applied several low- and high-tech methods for the detection of illicit connections in the same catchment (De Heuvel, the Netherlands). The methods included mesh wire screens for capturing coarse contamination, measurements of electroconductivity and temperature, sampling and quantification of Escherichia coli and extended-spectrum ß-lactamase-producing E. coli (ESBL-EC), DNA analysis via quantitative polymerase chain reaction for human-, dog-, and bird-specific fecal indicators, and distributed temperature sensing. Significant illicit connections could be identified using all methods. Nonetheless, hydraulic conditions and, predominantly, the sewage volume determine whether a misconnection can be detected by especially the low-tech methods. Using these results, the identified misconnections were repaired and biological and DNA analyses were repeated. Our results demonstrate that there were no changes in E. coli or ESBL-EC before and after mitigation, suggesting that these common markers of fecal contamination are not specific enough to evaluate the performance of mitigation efforts. However, a marked decrease in human wastewater markers (HF183) was observed.


Asunto(s)
Monitoreo del Ambiente , Aguas Residuales , Animales , Humanos , Perros , Monitoreo del Ambiente/métodos , Escherichia coli/genética , Aguas del Alcantarillado/análisis , Heces/química , ADN
15.
Opt Lett ; 47(4): 1001-1004, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-35167579

RESUMEN

Topological constant-intensity (TCI) waves are introduced in the context of non-Hermitian photonics. Unlike other known examples of topological defects, the proposed TCI waves exhibit a counterintuitive behavior because a phase difference occurs across space without any accompanying intensity variations. Such solutions exist only on non-Hermitian systems, because the associated nonzero phase difference is directly related to the real and imaginary parts of the potential. The free space diffraction and the existence of such waves in two spatial dimensions are also discussed in detail.

16.
Phys Rev Lett ; 128(18): 183901, 2022 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-35594088

RESUMEN

Coordinate transformations are a versatile tool to mold the flow of light, enabling a host of astonishing phenomena such as optical cloaking with metamaterials. Moving away from the usual restriction that links isotropic materials with conformal transformations, we show how nonconformal distortions of optical space are intimately connected to the complex refractive index distribution of an isotropic non-Hermitian medium. Remarkably, this insight can be used to circumvent the material requirement of working with refractive indices below unity, which limits the applications of transformation optics. We apply our approach to design a broadband unidirectional dielectric cloak, which relies on nonconformal coordinate transformations to tailor the non-Hermitian refractive index profile around a cloaked object. Our insights bridge the fields of two-dimensional transformation optics and non-Hermitian photonics.

17.
Phys Rev Lett ; 128(12): 123901, 2022 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-35394297

RESUMEN

We show that the orbital angular momentum (OAM) of a light field can be thermalized in a nonlinear cylindrical multimode optical waveguide. We find that upon thermal equilibrium, the maximization of the optical entropy leads to a generalized Rayleigh-Jeans distribution that governs the power modal occupancies with respect to the discrete OAM charge numbers. This distribution is characterized by a temperature that is by nature different from that associated with the longitudinal electromagnetic momentum flow of the optical field. Counterintuitively and in contrast to previous results, we demonstrate that even under positive temperatures, the ground state of the fiber is not always the most populated in terms of power. Instead, because of OAM, the thermalization processes may favor higher-order modes. A new equation of state is derived along with an extended Euler equation resulting from the extensivity of the entropy itself. By monitoring the nonlinear interaction between two multimode optical wave fronts with opposite spins, we show that the exchange of angular momentum is dictated by the difference in OAM temperatures, in full accord with the second law of thermodynamics. The theoretical analysis presented here is corroborated by numerical simulations that take into account the complex nonlinear dynamics of hundreds of modes. Our results may pave the way toward high-power optical sources with controllable orbital angular momenta, and at a more fundamental level, they may open up opportunities in drawing parallels with other complex multimode nonlinear systems like rotating atomic clouds.

18.
J Surg Res ; 276: 174-181, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-35366423

RESUMEN

INTRODUCTION: Adrenal mass management guidelines are insufficiently applied, and timeliness of treatment is unknown. We evaluated missed opportunities to promptly diagnose and treat adrenal tumors that ultimately required adrenalectomy. METHODS: From the Veterans Affairs Corporate Data Warehouse, we identified patients who underwent adrenalectomy (2010-2016) in the South-Central Veterans Affairs HealthCare Network and reviewed their records. Diagnostic timeliness was assessed by the interval between initial (index) imaging with adrenal abnormality and the next diagnostic step. Workup was defined as early (interval ≤6 mo) or late (>6 mo). Adrenalectomy was considered prompt when the interval between index imaging and adrenalectomy was ≤12 mo and delayed when this was >12 mo. We quantified diagnostic and treatment delays and assessed factors associated with delayed adrenalectomy. RESULTS: During the study period, 84 patients underwent adrenalectomy: male (86.9%), White (57.1%), with a mean age of 58.7 y (±8.8). Of those, 25 (29.8%) had late workup, and 36 (42.9%) had delayed surgery (median interval: 44 mo, range 14-282). Late hormonal workup occurred in 24 of 36 (66.7%) patients with delayed surgery, compared with one of 48 (2.1%, P < 0.001) with prompt surgery. CONCLUSIONS: Missed opportunities in prompt diagnosis and treatment were common in patients with adrenal masses ultimately requiring adrenalectomy. Late hormonal workup is associated with delayed adrenalectomy. Interventions are needed to aid clinicians to recognize the presence, promptly evaluate, and make guideline-informed decisions on the management of an adrenal mass.


Asunto(s)
Neoplasias de las Glándulas Suprarrenales , Laparoscopía , Neoplasias de las Glándulas Suprarrenales/diagnóstico , Neoplasias de las Glándulas Suprarrenales/cirugía , Adrenalectomía/métodos , Humanos , Laparoscopía/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
19.
Environ Res ; 212(Pt B): 113316, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35439459

RESUMEN

BACKGROUND: Exposure to various pesticides, such as pyrethroids and chlorpyrifos, has been previously associated with adverse effects on children's health. Scientific evidence on the human toxicity of glyphosate (GLY) and its primary metabolite, aminomethylphosphonic acid (AMPA) is limited, particularly for children. This study aimed to i) assess the exposure determinants of the studied pesticides measured in children in Cyprus, and ii) determine the association between the urinary pesticides and the biomarkers of DNA and lipid oxidative damage. METHODS: A children's health study was set up in Cyprus (ORGANIKO study) by aligning it with the methodology and tools used in the European Human Biomonitoring Initiative (HBM4EU). Urinary GLY and AMPA, pyrethroid metabolites and the chlorpyrifos metabolite TCPy were measured in 177 children aged 10-11 years old, using mass spectrometry. Oxidative stress was assessed with 8-iso-prostaglandin F2a (8-iso-PGF2α) as a marker of lipid damage and 8-hydroxy-2'-deoxyguanosine (8-OHdG) as a DNA oxidative damage marker, both measured with immunoassays. Questionnaires about demographic characteristics, pesticide usage, and dietary habits were filled out by the parents. Μultivariable regression models examined associations between pesticides and biomarkers of effect using two creatinine adjustments (cr1: adding it as covariate and cr2: biomarkers of exposure and effect were creatinine-adjusted). RESULTS: Parental educational level was a significant predictor of urinary pyrethroids but not for GLY/AMPA. Median [interquartile range, IQR] values for GLY and AMPA were  0.05). Similar significant associations with 8-OHdG were shown for a pyrethroid metabolite (3-PBA) and the chlorpyrifos metabolite (TCPy). No associations were observed between the aforementioned pesticides and 8-iso-PGF2α (p > 0.05). CONCLUSIONS: This is the first children's health dataset demonstrating the association between AMPA and DNA oxidative damage, globally. More data is needed to replicate the observed trends in other children's populations around the globe.


Asunto(s)
Cloropirifos , Plaguicidas , Piretrinas , Biomarcadores/orina , Niño , Cloropirifos/orina , Creatinina , Chipre , Glicina/análogos & derivados , Humanos , Lípidos , Organofosfonatos , Estrés Oxidativo , Plaguicidas/toxicidad , Piretrinas/orina , Instituciones Académicas , Ácido alfa-Amino-3-hidroxi-5-metil-4-isoxazol Propiónico , Glifosato
20.
Dig Dis Sci ; 67(3): 1007-1017, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-33751325

RESUMEN

BACKGROUND: Optimization of treatment with biologics is currently an unmet need for patients with ulcerative colitis (UC). Real-world studies provide neutral estimates of drug efficacy and safety within unselected patient populations and allow for the recognition of specific characteristics that affect response to therapy. AIMS: We aimed to depict the efficacy of vedolizumab in patients with UC in a real-world setting and identify prognosticators of improved outcomes. METHODS: Patients with active UC who commenced treatment with vedolizumab were prospectively followed up. Patient-reported outcomes (PROs) and clinical/endoscopic-reported outcomes were recorded at baseline and at weeks 14 and 54. Predefined endpoints of early and persistent efficacy were analyzed against clinical characteristics to identify prognostic factors for response. RESULTS: We included 96 patients (anti-TNF-exposed = 38.5%). At week 14, 73 patients (76%) had clinical response and 54 (56.3%) clinical remission. At week 54, the primary endpoint of vedolizumab persistence was met by 72 patients (75%), whereas steroid-free clinical remission by 59.4%. Among patients who had endoscopy, rates for mucosal healing (Mayo endoscopic score of 0) were 29.8% at week 14 and 44.6% at week 54, respectively. Vedolizumab treatment led to significant improvements in quality of life. Corticosteroid-refractory or anti-TNF-refractory disease, articular manifestations, and high baseline UC-PRO2 were associated with decreased efficacy of vedolizumab in the primary and secondary outcomes. CONCLUSIONS: Vedolizumab is characterized by high efficacy and long-term treatment persistence in UC. More aggressive disease, as indicated by refractoriness to steroids or anti-TNFs and elevated baseline PROs, may predict suboptimal response and help pre-treatment prognostic stratification of patients.


Asunto(s)
Colitis Ulcerosa , Anticuerpos Monoclonales Humanizados , Colitis Ulcerosa/inducido químicamente , Colitis Ulcerosa/diagnóstico , Colitis Ulcerosa/tratamiento farmacológico , Fármacos Gastrointestinales/efectos adversos , Grecia , Humanos , Calidad de Vida , Inducción de Remisión , Estudios Retrospectivos , Esteroides/uso terapéutico , Resultado del Tratamiento , Inhibidores del Factor de Necrosis Tumoral
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