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1.
Cell ; 156(3): 577-89, 2014 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-24485461

RESUMEN

Auxin regulates numerous plant developmental processes by controlling gene expression via a family of functionally distinct DNA-binding auxin response factors (ARFs), yet the mechanistic basis for generating specificity in auxin response is unknown. Here, we address this question by solving high-resolution crystal structures of the pivotal Arabidopsis developmental regulator ARF5/MONOPTEROS (MP), its divergent paralog ARF1, and a complex of ARF1 and a generic auxin response DNA element (AuxRE). We show that ARF DNA-binding domains also homodimerize to generate cooperative DNA binding, which is critical for in vivo ARF5/MP function. Strikingly, DNA-contacting residues are conserved between ARFs, and we discover that monomers have the same intrinsic specificity. ARF1 and ARF5 homodimers, however, differ in spacing tolerated between binding sites. Our data identify the DNA-binding domain as an ARF dimerization domain, suggest that ARF dimers bind complex sites as molecular calipers with ARF-specific spacing preference, and provide an atomic-scale mechanistic model for specificity in auxin response.


Asunto(s)
Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/metabolismo , ADN/metabolismo , Ácidos Indolacéticos/metabolismo , Factores de Transcripción/química , Factores de Transcripción/metabolismo , Secuencia de Aminoácidos , Cristalografía por Rayos X , ADN/química , Dimerización , Modelos Moleculares , Datos de Secuencia Molecular , Filogenia , Estructura Terciaria de Proteína , Alineación de Secuencia
2.
Genes Dev ; 30(20): 2286-2296, 2016 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-27898393

RESUMEN

Tissue patterning in multicellular organisms is the output of precise spatio-temporal regulation of gene expression coupled with changes in hormone dynamics. In plants, the hormone auxin regulates growth and development at every stage of a plant's life cycle. Auxin signaling occurs through binding of the auxin molecule to a TIR1/AFB F-box ubiquitin ligase, allowing interaction with Aux/IAA transcriptional repressor proteins. These are subsequently ubiquitinated and degraded via the 26S proteasome, leading to derepression of auxin response factors (ARFs). How auxin is able to elicit such a diverse range of developmental responses through a single signaling module has not yet been resolved. Here we present an alternative auxin-sensing mechanism in which the ARF ARF3/ETTIN controls gene expression through interactions with process-specific transcription factors. This noncanonical hormone-sensing mechanism exhibits strong preference for the naturally occurring auxin indole 3-acetic acid (IAA) and is important for coordinating growth and patterning in diverse developmental contexts such as gynoecium morphogenesis, lateral root emergence, ovule development, and primary branch formation. Disrupting this IAA-sensing ability induces morphological aberrations with consequences for plant fitness. Therefore, our findings introduce a novel transcription factor-based mechanism of hormone perception in plants.


Asunto(s)
Arabidopsis/crecimiento & desarrollo , Arabidopsis/genética , Regulación de la Expresión Génica de las Plantas/genética , Ácidos Indolacéticos/metabolismo , Morfogénesis/genética , Arabidopsis/enzimología , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas F-Box/metabolismo , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Unión Proteica , Proteínas Serina-Treonina Quinasas/metabolismo , Receptores de Superficie Celular/metabolismo , Factores de Transcripción/metabolismo
3.
Proc Natl Acad Sci U S A ; 117(39): 24557-24566, 2020 09 29.
Artículo en Inglés | MEDLINE | ID: mdl-32929017

RESUMEN

The hormone auxin controls many aspects of the plant life cycle by regulating the expression of thousands of genes. The transcriptional output of the nuclear auxin signaling pathway is determined by the activity of AUXIN RESPONSE transcription FACTORs (ARFs), through their binding to cis-regulatory elements in auxin-responsive genes. Crystal structures, in vitro, and heterologous studies have fueled a model in which ARF dimers bind with high affinity to distinctly spaced repeats of canonical AuxRE motifs. However, the relevance of this "caliper" model, and the mechanisms underlying the binding affinities in vivo, have remained elusive. Here we biochemically and functionally interrogate modes of ARF-DNA interaction. We show that a single additional hydrogen bond in Arabidopsis ARF1 confers high-affinity binding to individual DNA sites. We demonstrate the importance of AuxRE cooperativity within repeats in the Arabidopsis TMO5 and IAA11 promoters in vivo. Meta-analysis of transcriptomes further reveals strong genome-wide association of auxin response with both inverted (IR) and direct (DR) AuxRE repeats, which we experimentally validated. The association of these elements with auxin-induced up-regulation (DR and IR) or down-regulation (IR) was correlated with differential binding affinities of A-class and B-class ARFs, respectively, suggesting a mechanistic basis for the distinct activity of these repeats. Our results support the relevance of high-affinity binding of ARF transcription factors to uniquely spaced DNA elements in vivo, and suggest that differential binding affinities of ARF subfamilies underlie diversity in cis-element function.


Asunto(s)
Proteínas de Arabidopsis/metabolismo , Arabidopsis/metabolismo , Proteínas de Unión al ADN/metabolismo , Regulación de la Expresión Génica de las Plantas , Elementos de Respuesta , Factores de Transcripción/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/genética , Factores de Transcripción con Motivo Hélice-Asa-Hélice Básico/metabolismo , Proteínas de Unión al ADN/genética , Estudio de Asociación del Genoma Completo , Ácidos Indolacéticos/metabolismo , Secuencias Invertidas Repetidas , Familia de Multigenes , Secuencias Repetitivas de Ácidos Nucleicos , Factores de Transcripción/genética
4.
J Acoust Soc Am ; 154(5): 2757-2768, 2023 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-37909711

RESUMEN

This paper reports on an observation of three-dimensional (3D) arrivals for which the change in the direction of horizontally refracted sound is nearly 180°. The experimental site is Jan Mayen Channel (JMCh), which connects the Greenland and Norwegian Seas. During the experiment, signals from a moored source transmitting a 500-1500 Hz sweep every 4 h were recorded by three surface drifters equipped with hydrophone arrays. Over a 3-day period, the drifters moved north across JMCh toward the moored source. In each recording, an in-plane arrival is identified. In a subset of these recordings, a second arrival is observed, having travel time consistent with propagation from the moored source, turning at the ridge on the south side of the channel, and arriving at the drifters. In a smaller subset of recordings, a third arrival is also observed having travel time consistent with a turning point on the face of the bathymetric rise on the west end of the channel that forms the Jan Mayen volcano. A 3D ray trace is employed to show the change in direction results from repeated reflections from the seafloor such that it is classified as horizontal refraction and not a single-bounce reflection.

5.
Medicina (Kaunas) ; 59(9)2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37763654

RESUMEN

Breast milk (BM) is a constantly changing fluid that represents the primary source of nutrition for newborns. It is widely recognized that breastfeeding provides benefits for both the child and the mother, including a lower risk of ovarian and breast cancer, type 2 diabetes mellitus, decreased blood pressure, and more. In infants, breastfeeding has been correlated with a lower risk of infectious diseases, obesity, lower blood pressure, and decreased incidence of respiratory infections, diabetes, and asthma. Various factors, such as the baby's sex, the health status of the mother and child, the mother's diet, and the mode of delivery, can affect the composition of breast milk. This review focuses on the biological impact of the nutrients in BM on the development and functionality of vital organs to promote the benefit of health.

6.
Medicina (Kaunas) ; 59(11)2023 Oct 28.
Artículo en Inglés | MEDLINE | ID: mdl-38003956

RESUMEN

Adipose tissue and liver metabolism play a key role in maintaining body homeostasis; therefore, their impairment conduces a pathological state. Nowadays, occidental lifestyle is a common etiological issue among a variety of chronic diseases, while diet is a unique strategy to prevent obesity and liver metabolism impairment and is a powerful player in the treatment of metabolic-related diseases. Mesoamerican foods are rich in bioactive molecules that enhance and improve adipose tissue and liver performance and represent a prophylactic and therapeutic alternative for disorders related to the loss of homeostasis in the metabolism of these two important tissues.


Asunto(s)
Tejido Adiposo , Enfermedades Metabólicas , Humanos , Tejido Adiposo/metabolismo , Hígado , Obesidad/metabolismo , Enfermedades Metabólicas/metabolismo , Homeostasis , Metabolismo Energético
7.
Int J Mol Sci ; 23(6)2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35328562

RESUMEN

SARS-CoV-2 variants surveillance is a worldwide task that has been approached with techniques such as Next Generation Sequencing (NGS); however, this technology is not widely available in developing countries because of the lack of equipment and limited funding in science. An option is to deploy a RT-qPCR screening test which aids in the analysis of a higher number of samples, in a shorter time and at a lower cost. In this study, variants present in samples positive for SARS-CoV-2 were identified with a RT-qPCR mutation screening kit and were later confirmed by NGS. A sample with an abnormal result was found with the screening test, suggesting the simultaneous presence of two viral populations with different mutations. The DRAGEN Lineage analysis identified the Delta variant, but there was no information about the other three mutations previously detected. When the sequenced data was deeply analyzed, there were reads with differential mutation patterns, that could be identified and classified in terms of relative abundance, whereas only the dominant population was reported by DRAGEN software. Since most of the software developed to analyze SARS-CoV-2 sequences was aimed at obtaining the consensus sequence quickly, the information about viral populations within a sample is scarce. Here, we present a faster and deeper SARS-CoV-2 surveillance method, from RT-qPCR screening to NGS analysis.


Asunto(s)
COVID-19/diagnóstico , Análisis Mutacional de ADN/métodos , Genoma Viral/genética , Mutación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa/métodos , SARS-CoV-2/genética , COVID-19/epidemiología , COVID-19/virología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Humanos , Pandemias/prevención & control , Reproducibilidad de los Resultados , SARS-CoV-2/fisiología , Sensibilidad y Especificidad
8.
Molecules ; 27(23)2022 Nov 24.
Artículo en Inglés | MEDLINE | ID: mdl-36500272

RESUMEN

Before formulating radiopharmaceuticals for injection, it is necessary to remove various impurities via purification. Conventional synthesis methods involve relatively large quantities of reagents, requiring high-resolution and high-capacity chromatographic methods (e.g., semi-preparative radio-HPLC) to ensure adequate purity of the radiopharmaceutical. Due to the use of organic solvents during purification, additional processing is needed to reformulate the radiopharmaceutical into an injectable buffer. Recent developments in microscale radiosynthesis have made it possible to synthesize radiopharmaceuticals with vastly reduced reagent masses, minimizing impurities. This enables purification with lower-capacity methods, such as analytical HPLC, with a reduction of purification time and volume (that shortens downstream re-formulation). Still, the need for a bulky and expensive HPLC system undermines many of the advantages of microfluidics. This study demonstrates the feasibility of using radio-TLC for the purification of radiopharmaceuticals. This technique combines high-performance (high-resolution, high-speed separation) with the advantages of a compact and low-cost setup. A further advantage is that no downstream re-formulation step is needed. Production and purification of clinical scale batches of [18F]PBR-06 and [18F]Fallypride are demonstrated with high yield, purity, and specific activity. Automating this radio-TLC method could provide an attractive solution for the purification step in microscale radiochemistry systems.


Asunto(s)
Microfluídica , Radiofármacos , Radiofármacos/química , Cromatografía en Capa Delgada , Radioquímica/métodos , Cromatografía Líquida de Alta Presión/métodos
9.
Int J Mol Sci ; 22(5)2021 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-33807788

RESUMEN

Development in multicellular organisms relies on cell proliferation and specialization. In plants, both these processes critically depend on the spatial organization of cells within a tissue. Owing to an absence of significant cellular migration, the relative position of plant cells is virtually made permanent at the moment of division. Therefore, in numerous plant developmental contexts, the (divergent) developmental trajectories of daughter cells are dependent on division plane positioning in the parental cell. Prior to and throughout division, specific cellular processes inform, establish and execute division plane control. For studying these facets of division plane control, the moss Physcomitrium (Physcomitrella) patens has emerged as a suitable model system. Developmental progression in this organism starts out simple and transitions towards a body plan with a three-dimensional structure. The transition is accompanied by a series of divisions where cell fate transitions and division plane positioning go hand in hand. These divisions are experimentally highly tractable and accessible. In this review, we will highlight recently uncovered mechanisms, including polarity protein complexes and cytoskeletal structures, and transcriptional regulators, that are required for 1D to 3D body plan formation.


Asunto(s)
Bryopsida , División Celular/fisiología , Células Vegetales/metabolismo , Desarrollo de la Planta/fisiología , Bryopsida/citología , Bryopsida/crecimiento & desarrollo
10.
Int J Mol Sci ; 22(15)2021 Aug 02.
Artículo en Inglés | MEDLINE | ID: mdl-34361064

RESUMEN

Carbohydrates and lipids are two components of the diet that provide the necessary energy to carry out various physiological processes to help maintain homeostasis in the body. However, when the metabolism of both biomolecules is altered, development of various liver diseases takes place; such as metabolic-associated fatty liver diseases (MAFLD), hepatitis B and C virus infections, alcoholic liver disease (ALD), and in more severe cases, hepatocelular carcinoma (HCC). On the other hand, PPARs are a family of ligand-dependent transcription factors with an important role in the regulation of metabolic processes to hepatic level as well as in other organs. After interaction with specific ligands, PPARs are translocated to the nucleus, undergoing structural changes to regulate gene transcription involved in lipid metabolism, adipogenesis, inflammation and metabolic homeostasis. This review aims to provide updated data about PPARs' critical role in liver metabolic regulation, and their involvement triggering the genesis of several liver diseases. Information is provided about their molecular characteristics, cell signal pathways, and the main pharmacological therapies that modulate their function, currently engaged in the clinic scenario, or in pharmacological development.


Asunto(s)
Hepatopatías/tratamiento farmacológico , Hepatopatías/patología , Receptores Activados del Proliferador del Peroxisoma/metabolismo , Preparaciones Farmacéuticas/administración & dosificación , Animales , Humanos , Hepatopatías/metabolismo , Terapia Molecular Dirigida
11.
Gac Med Mex ; 157(5): 508-515, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-35104268

RESUMEN

BACKGROUND AND OBJECTIVES: Gene therapy using urokinase-type plasminogen activator (uPA) has been shown to induce extracellular matrix degradation, hepatocyte proliferation and liver tissue function restoration in liver cirrhosis models. Physiologically, uPA activates plasminogen conversion to plasmin, which leads, depending on the organ, to thrombolysis or extracellular matrix degradation. The purpose of this study was to compare the regenerative effect of gene therapy with adenoviruses encoding wild-type uPA (huPA), as well as its truncated isoform (ΔhuPA), in healthy and cirrhotic animals. In addition, possible adverse effects on coagulation were assessed. METHODS: 6 x 1011 vp/kg of Ad-huPA or Ad-ΔhuPA were administered via the iliac vein to healthy male Wistar rats or to male Wistar rats with cirrhosis induced by chronic poisoning with carbon tetrachloride (CCl4). The animals were sacrificed at day 2, 4 or 6 post-treatment. Liver fibrosis, proliferating cell nuclear antigen expression, alanine aminotransferase (ALT) and aspartate aminotransferase (AST) serum levels and coagulation markers were evaluated. RESULTS: On day 6 post-treatment, a fibrosis reversal of 48.7-41.5% was achieved. AST and ALT levels did not change in cirrhotic animals treated with ΔhuPA, but showed an elevation in healthy animals. Cell proliferation increased in healthy and cirrhotic animals with both transgene isoforms. No coagulation adverse effects were observed in the ΔhuPA group, and by day 6, they had disappeared in the huPA group. CONCLUSIONS: Gene therapy with Ad-huPA and Ad-ΔhuPA favors cell proliferation in cirrhotic animals, without important side effects.


ANTECEDENTES Y OBJETIVOS: La terapia génica empleando el activador de plasminógeno tipo urocinasa (huPA) ha demostrado que induce la degradación de matriz extracelular, la proliferación de hepatocitos y el restablecimiento de la funcionalidad tisular en modelos de cirrosis hepática. Fisiológicamente, el uPA activa la conversión del plasminógeno en plasmina, lo que conlleva, dependiendo del órgano, una trombólisis o a degradación de la matriz extracelular. El objetivo de este estudio fue comparar el efecto regenerador de la terapia génica con adenovirus codificando la forma silvestre (huPA), así como su isoforma truncada (DhuPA) en animales sanos y cirróticos. Además, se valoraron los posibles efectos adversos sobre la coagulación. MÉTODOS: Se administró 6x1011 pv/kg del Ad-huPA o Ad-ΔhuPA a ratas Wistar macho sanas o con cirrosis por intoxicación crónica con tetracloruro de carbono (CCl4) vía vena ilíaca. El sacrificio fue al día 2, 4 o 6 postratamiento. Se evaluó la fibrosis hepática, la expresión de antígeno nuclear de proliferación celular y niveles séricos de alanina aminotransferasa (ALT) y aspartato aminotransferasa (AST), y marcadores de coagulación. RESULTADOS: Al día 6 postratamiento se alcanzó una reversión de fibrosis del 48.7-41.5%. Los niveles de AST y ALT no cambiaron en animales cirróticos tratados con DhuPA, pero aumentaron en animales sanos comparados con el control sano no tratado. La proliferación aumenta en animales sanos y cirróticos con ambas isoformas del transgén. No se observaron efectos adversos en la coagulación en el grupo DhuPA y para el día 6 habían desaparecido en el grupo huPA. CONCLUSIONES: La terapia génica con Ad-uPA y Ad-ΔhuPA favorece la proliferación celular en animales cirróticos, sin efectos secundarios importantes.


Asunto(s)
Hígado , Activador de Plasminógeno de Tipo Uroquinasa , Animales , Tetracloruro de Carbono , Terapia Genética , Masculino , Ratas , Ratas Wistar , Activador de Plasminógeno de Tipo Uroquinasa/genética
13.
Proc Natl Acad Sci U S A ; 113(24): 6683-8, 2016 06 14.
Artículo en Inglés | MEDLINE | ID: mdl-27226297

RESUMEN

The remarkable adaptive strategies of insects to extreme environments are linked to the biochemical compounds in their body fluids. Trehalose, a versatile sugar molecule, can accumulate to high levels in freeze-tolerant and freeze-avoiding insects, functioning as a cryoprotectant and a supercooling agent. Antifreeze proteins (AFPs), known to protect organisms from freezing by lowering the freezing temperature and deferring the growth of ice, are present at high levels in some freeze-avoiding insects in winter, and yet, paradoxically are found in some freeze-tolerant insects. Here, we report a previously unidentified role for AFPs in effectively inhibiting trehalose precipitation in the hemolymph (or blood) of overwintering beetle larvae. We determine the trehalose level (29.6 ± 0.6 mg/mL) in the larval hemolymph of a beetle, Dendroides canadensis, and demonstrate that the hemolymph AFPs are crucial for inhibiting trehalose crystallization, whereas the presence of trehalose also enhances the antifreeze activity of AFPs. To dissect the molecular mechanism, we examine the molecular recognition between AFP and trehalose crystal interfaces using molecular dynamics simulations. The theory corroborates the experiments and shows preferential strong binding of the AFP to the fast growing surfaces of the sugar crystal. This newly uncovered role for AFPs may help explain the long-speculated role of AFPs in freeze-tolerant species. We propose that the presence of high levels of molecules important for survival but prone to precipitation in poikilotherms (their body temperature can vary considerably) needs a companion mechanism to prevent the precipitation and here present, to our knowledge, the first example. Such a combination of trehalose and AFPs also provides a novel approach for cold protection and for trehalose crystallization inhibition in industrial applications.


Asunto(s)
Proteínas Anticongelantes/química , Frío , Escarabajos/química , Hemolinfa/química , Proteínas de Insectos/química , Simulación de Dinámica Molecular , Trehalosa/química , Animales , Proteínas Anticongelantes/metabolismo , Escarabajos/metabolismo , Hemolinfa/metabolismo , Proteínas de Insectos/metabolismo , Trehalosa/metabolismo
14.
J Electrochem Soc ; 164(9): G99-G103, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28890550

RESUMEN

Electrochemical fluorination of methyl(phenylthio)acetate was achieved using tetrabutylammonium fluoride (TBAF). Electrochemical fluorination was performed under potentiostatic anodic oxidation using an undivided cell in acetonitrile containing TBAF and triflic acid. The influence of several parameters including: oxidation potential, time, temperature, sonication, TBAF concentration and triflic acid concentration on fluorination efficiency were studied. It was found that the triflic acid to TBAF concentration ratio plays a key role in the fluorination efficiency. Electrochemical fluorination resulted in formation of mono-fluorinated methyl 2-fluoro-2-(phenylthio)acetate verified by gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) Spectroscopy. Under optimum conditions 44 ± 3% mono fluorination yield was obtained after a 30 min electrolysis. Electrochemical radiofluorination for the synthesis of methyl 2-[18F]fluoro-2-(phenothio) acetate was also achieved with the same optimized electrochemical cell parameters where TBAF was first passed through an anion exchange resin containing fluorine-18. A radiochemical fluorination efficiency of 7 ± 1% was achieved after 30 min of electrolysis.

15.
Am J Orthod Dentofacial Orthop ; 146(1): 92-7, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24975003

RESUMEN

INTRODUCTION: Orthodontic tooth movement implies application of forces that generate an inflammatory process. The myeloperoxidase (MPO) enzyme is found inside neutrophil granules. MPO activity indirectly reflects the level of inflammation. The aim of this study was to measure MPO activity in gingival crevicular fluid (GCF) and whole saliva in orthodontic patients with different levels of dental crowding at the alignment phase of orthodontic treatment with the same archwires. METHODS: Twenty patients were classified according to the irregularity index into 2 groups: severe and minimum crowding (10 in each group). MPO activity was evaluated in GCF and saliva at 0 and 2 hours, and 7 and 14 days after the orthodontic appliances were activated. MPO activity was measured using the modified Bradley-Bozeman technique. RESULTS: In both groups, the maximum activity was at 2 hours (P <0.05) after activation. MPO activity remained elevated until day 7, and values similar to baseline were found at day 14 in the GCF and saliva samples. Enzymatic activity did not show statistical differences between the groups. CONCLUSIONS: The amount of dental crowding does not seem to influence MPO activity, which showed similar patterns in GCF and saliva, but the values in GCF reflected the inflammatory changes more accurately than did the values in saliva. The quantification of MPO activity is a useful biologic marker as an indirect measurement of inflammation generated with tooth movement independent of the amount of crowding.


Asunto(s)
Líquido del Surco Gingival/enzimología , Maloclusión/terapia , Peroxidasa/análisis , Saliva/enzimología , Técnicas de Movimiento Dental/métodos , Biomarcadores/análisis , Aleaciones Dentales/química , Elastómeros/química , Femenino , Estudios de Seguimiento , Humanos , Masculino , Maloclusión/clasificación , Níquel/química , Soportes Ortodóncicos , Alambres para Ortodoncia , Proteínas y Péptidos Salivales/análisis , Titanio/química , Técnicas de Movimiento Dental/instrumentación , Adulto Joven
16.
Acta Gastroenterol Latinoam ; 44(1): 48-51, 2014 Mar.
Artículo en Español | MEDLINE | ID: mdl-24847630

RESUMEN

Pneumatosis cystoides intestinalis features the presence of subserum or submucous cysts with gas in the intestinal wall. Its prevalence is 0.03%, although it has increased in the past decades due to a greater use of colonoscopy in everyday medical practice. Though there are several theories about its origin and many associated diseases were reported, its pathogenesis still remains uncertain. It is generally diagnosed as a finding in an imaging test. The treatment depends on the severity of the associated disease and symptoms. We report the case of a 59-year-old woman, heavy smoker, with no other clinical conditions who took a medical consultation due to abdominal bloating. She underwent a screening colonoscopy which detected the existence of cysts on the colonic wall. Afterwards, a computed tomography was performed and showed apical lung bullae, gas in a colonic wall segment, and ascitis associated to a big anexial tumor. She underwent a cytoreductive surgery, confirming the presence of advanced ovary neoplasm. The endoscopic biopsy confirmed the diagnosis of penumatosis cystoides intestinalis. We report these case because it is a rare entity which requires uncommon management and treatment guidelines.


Asunto(s)
Neoplasias Ováricas/diagnóstico , Neumatosis Cistoide Intestinal/diagnóstico , Biopsia , Colonoscopía , Femenino , Humanos , Persona de Mediana Edad , Neoplasias Ováricas/complicaciones , Neumatosis Cistoide Intestinal/complicaciones , Neumatosis Cistoide Intestinal/cirugía , Tomografía Computarizada por Rayos X
17.
Clin Ophthalmol ; 18: 2439-2451, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39233999

RESUMEN

Background: This research aims to investigate the influence of environmental factors on the treatment efficacy of ocular lubricants in patients from urban areas with dry eye disease (DED). Methods: A phase IV clinical trial, which included 173 patients from major cities in Mexico, was randomly assigned to use ocular lubricants four times a day for 30 days. Ocular Surface Disease Index (OSDI), noninvasive tear film break-up time (NIBUT), ocular staining, and conjunctival hyperemia (CH) among other factors like weather, and air pollution as covariates were analysed. Results: After 30 days, OSDI score decreased by 14.8 points (p<0.001), and NIBUT increased by 2.9 seconds (p< 0.001), with longer values observed in patients recruited in autumn and winter (additional 1.8 seconds, p< 0.05) compared to those recruited in spring. Patients living in cities with cooler weather and high humidity, but low air quality had higher OSDI and conjunctival stain scores of up to 4.4 and 0.3 points, respectively, as compared to those living in cities with similar pollution and humidity levels but with higher temperatures (p-values= 0.019 and 0.050). Patients with moderate CH had an increase of up to 0.8 points in their corneal stain score (p< 0.010). We also found that ozone levels were related to the predicted changes in OSDI and NIBUT. Conclusion: This study demonstrated the impact of environmental factors on the signs and symptoms of DED and suggests that patients residing in cities with inadequately controlled air pollution can benefit from using ocular lubricants to alleviate their symptoms. Trial Registration: Trial is registered at clinicaltrials.gov (NCT04702776).

18.
Glob Chall ; 7(8): 2300012, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37635701

RESUMEN

Transnational public-private governance initiatives (TGIs) have become key elements in global governance, especially in the governance of sustainability. Pertinent research has concentrated on why TGIs have emerged as well as on their impacts on political outcomes and questions related to their legitimacy. This instructive literature has predominantly focused on TGIs as entities in their own right. This explorative study contributes to the literature by advocating a complementary analytical perspective that pays attention to domestic-level patterns of participation in TGIs and national factors that determine which types of organizations (public, business, or civil society) participate in TGIs. It is shown for six Latin American countries (Argentina, Brazil, Chile, Colombia, Mexico, and Peru) that there exists cross-country variation in the composition patterns in 29 TGIs on sustainability, suggesting that national conditions matter for how organizations participate in them. By improving the knowledge of the national conditions, a more complete analysis of participation and the effectiveness of TGIs can be provided in global sustainability governance. In this spirit, in a last step, an agenda is developed for guiding future research on this topic.

19.
Anal Methods ; 15(3): 377-387, 2023 01 19.
Artículo en Inglés | MEDLINE | ID: mdl-36542448

RESUMEN

The list of new positron-emission tomography (PET) tracers has rapidly grown in the past decade, following discoveries of new biological targets and therapeutic strategies, with several compounds garnering recent regulatory approval for clinical use. During the development of synthesis methods and production of new tracers for imaging, analytical methods for radio-high performance liquid chromatography (radio-HPLC) and radio-thin layer chromatography (radio-TLC) separations need to be developed to assess radiochemical compositions. Radio-TLC is often faster, simpler, and sometimes more accurate than radio-HPLC (as there is no underestimation of [18F]fluoride when analyzing 18F-labeled radiopharmaceuticals). Many protocols have been developed for separating 18F-radiopharmaceuticals on silica TLC plates, typically with [18F]fluoride retained at the origin and the radiopharmaceutical (and impurities) migrating along the plate. Interestingly, many reports describe the use of aqueous conditions to mobilize polar species, but it is known that aqueous conditions can modify silica and alter its chromatographic behavior. In this technical note, we explore the effects that aqueous conditions have on the analysis of 18F-radiopharmaceutical mixtures, revealing that with sufficient water, the radionuclide ([18F]fluoride) can migrate away from the origin and can be split into multiple bands. Furthermore, water can hinder the migration of the radiopharmaceutical. These effects can lead to overlapped bands or reversal of the normally expected order of bands, potentially leading to the misinterpretation of results if care is not taken to validate the TLC method carefully.


Asunto(s)
Fluoruros , Radiofármacos , Radiofármacos/efectos adversos , Radiofármacos/química , Cromatografía en Capa Delgada , Agua , Dióxido de Silicio
20.
J Chromatogr A ; 1687: 463656, 2023 Jan 04.
Artículo en Inglés | MEDLINE | ID: mdl-36463649

RESUMEN

Radiopharmaceutical analysis is limited by conventional methods. Radio-HPLC may be inaccurate for some compounds (e.g., 18F-radiopharmaceuticals) due to radionuclide sequester. Radio-TLC is simpler, faster, and detects all species but has limited resolution. Imaging-based readout of TLC plates (e.g., using Cerenkov luminescence imaging) can improve readout resolution, but the underlying chromatographic separation efficiency may be insufficient to resolve chemically similar species such as product and precursor-derived impurities. This study applies a systematic mobile phase optimization method, PRISMA, to improve radio-TLC resolution. The PRISMA method optimizes the mobile phase by selecting the correct solvent, optimizing solvent polarity, and optimizing composition. Without prior knowledge of impurities and by simply observing the separation resolution between a radiopharmaceutical and its nearest radioactive or non-radioactive impurities (observed via UV imaging) for different mobile phases, the PRISMA method enabled the development of high-resolution separation conditions for a wide range of 18F-radiopharmaceuticals ( [18F]PBR-06, [18F]FEPPA, [18F]Fallypride, [18F]FPEB, and [18F]FDOPA). Each optimization required a single batch of crude radiopharmaceutical and a few hours. Interestingly, the optimized TLC method provided greater accuracy (compared to other published TLC methods) in determining the product abundance of one radiopharmaceutical studied in more depth ( [18F]Fallypride) and was capable of resolving a comparable number of species as isocratic radio-HPLC. We used the PRISMA-optimized mobile phase for [18F]FPEB in combination with multi-lane radio-TLC techniques to evaluate reaction performance during high-throughput synthesis optimization of [18F]FPEB. The PRISMA methodology, in combination with high-resolution radio-TLC readout, enables a rapid and systematic approach to achieving high-resolution and accurate analysis of radiopharmaceuticals without the need for radio-HPLC.


Asunto(s)
Benzamidas , Radiofármacos , Cromatografía en Capa Delgada/métodos , Cromatografía Líquida de Alta Presión , Solventes
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