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1.
JPGN Rep ; 5(2): 170-174, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38756112

RESUMEN

Mucosal prolapse syndrome (MPS) is a rare group of benign conditions characterized by a set of unifying histologic findings thought to be the result of repeated mucosal shearing and submucosal vascular congestion caused by straining. This set of conditions is often misdiagnosed as other polyposis syndromes, inflammatory bowel disease, or malignancy due to its clinical presentation, appearance, and rarity. We report a case of a 15-year-old male who presented with painless rectal bleeding. He was found to have four rectal polyps thought to be due to Peutz-Jeghers syndrome. A repeat colonoscopy with biopsies a year later revealed a diagnosis of MPS. Our case highlights the morphologic similarity between hamartomatous polyp and mucosal prolapse histology. Since MPS is a rare diagnosis even among the adult population, it has not been well described in pediatrics. This syndrome should be on the differential diagnosis for pediatric rectal polyps to prevent unnecessary invasive testing and a delay in treatment.

2.
Artículo en Inglés | MEDLINE | ID: mdl-38801072

RESUMEN

OBJECTIVE: A constitutional disease-causing variant (DCV) in the SMAD4 or BMPR1A genes is present in 40%-60% of patients with juvenile polyposis syndrome (JPS). The aim of this study was to characterize the clinical course and polyp burden in children with DCV-positive JPS compared to DCV-negative JPS. METHODS: Demographic, clinical, genetic, and endoscopic data of children with JPS were compiled from eight international centers in the ESPHGAN/NASPGHAN polyposis working group. RESULTS: A total of 124 children with JPS were included: 69 (56%) DCV-negative and 55 (44%) DCV-positive (53% SMAD4 and 47% BMPR1A) with a median (interquartile range [IQR]) follow-up of 4 (2.8-6.4) years. DCV-positive children were diagnosed at an older age compared to DCV-negative children [12 (8-15.7) years vs. 5 (4-7) years, respectively, p < 0.001], had a higher frequency of family history of polyposis syndromes (50.9% vs. 1.4%, p < 0.001), experienced a greater frequency of extraintestinal manifestations (27.3% vs. 5.8%, p < 0.001), and underwent more gastrointestinal surgeries (16.4% vs. 1.4%, p = 0.002). The incidence rate ratio for the development of new colonic polyps was 6.15 (95% confidence interval 3.93-9.63, p < 0.001) in the DCV-positive group compared to the DCV-negative group, with an average of 12.2 versus 2 new polyps for every year of follow-up. There was no difference in the burden of polyps between patients with SMAD4 and BMPR1A mutations. CONCLUSIONS: This largest international cohort of pediatric JPS revealed that DCV-positive and DCV-negative children exhibit distinct clinical phenotype. These findings suggest a potential need of differentiated surveillance strategies based upon mutation status.

3.
Rev. colomb. cir ; 39(2): 299-307, 20240220. tab
Artículo en Español | LILACS | ID: biblio-1532686

RESUMEN

Introducción. El aneurisma de la aorta abdominal (AAA) es la dilatación de la aorta abdominal mayor de 1,5 veces el diámetro esperado. Su prevalencia es variable, con tasas reportadas de hasta el 12,5 %. Se considera como causa de muerte de más de 10.000 personas al año en los Estados Unidos. El objetivo de esta revisión de la literatura fue describir los factores de riesgo y las herramientas de tamizaje de AAA. Métodos. Se realizó una búsqueda de la literatura utilizando dos ecuaciones en bases de datos electrónicas, empleando términos seleccionados de "Medical Subject Heading" (MeSH) y "Descriptores en Ciencias de la Salud" (DeCS). Se evaluó la calidad de los estudios con la herramienta STROBE (Strengthening the Reporting of Observational Studies in Epidemiology). Resultados. Se recolectaron 40 artículos y a partir de ellos se construyó el texto de revisión, identificando en estos, los factores de riesgo asociados al desarrollo de AAA, tales como sexo masculino, tabaquismo, hipertensión arterial, antecedente familiar y obesidad, entre otros. La diabetes mellitus parece actuar como factor protector. Dentro de los instrumentos de tamizaje, el ultrasonido abdominal es uno de los más usados. Conclusión. El AAA es una patología multifactorial. En la actualidad la ultrasonografía de aorta es el método de elección para el tamizaje, permitiendo la detección precoz. El tamizaje de AAA con métodos no invasivos, como el ultrasonido, es útil sobre todo en zonas con prevalencia alta de la patología y en pacientes con determinados factores de riesgo.


Introduction. Abdominal aortic aneurysm (AAA) is a dilation of the abdominal aorta greater than 1.5 times the expected diameter. Its prevalence is variable, with reported rates of up to 12.5%. It is considered the cause of death of more than 10,000 people a year in the United States. The objective of this literature review was to describe risk factors and screening tools for AAA. Methods. A literature search was conducted using two equations in electronic databases, using terms selected from "Medical Subject Heading" (MeSH) and "Descriptors in Health Sciences" (DeCS). The quality of the studies was evaluated with the STROBE (Strengthening the Reporting of Observational Studies in Epidemiology) tool. Results. Forty articles were collected and from them the review text was constructed, identifying the risk factors associated with the development of AAA, such as male sex, smoking, high blood pressure, family history and obesity, among others. Diabetes mellitus seems to act as a protective factor. Among the screening instruments, abdominal ultrasound is one of the most used. Conclusion. AAA is a multifactorial pathology. Currently, aortic ultrasonography is the method of choice for screening, allowing early detection. Screening for AAA with non-invasive methods, such as ultrasound, is useful especially in areas with a high prevalence of this pathology and in patients with certain risk factors.


Asunto(s)
Humanos , Tamizaje Masivo , Aneurisma de la Aorta Abdominal , Angiografía por Tomografía Computarizada , Enfermedades de la Aorta , Tabaquismo , Ultrasonografía
4.
Sportis (A Coruña) ; 10(1): 131-157, 2024. ilus, tab
Artículo en Español | IBECS | ID: ibc-229139

RESUMEN

Para la evaluación del fitness cardiorrespiratorio existen pruebas directas en laboratorio que proporcionan información objetiva respecto a esta cualidad. No obstante, cuando no se cuenta con los recursos se recurre al uso de pruebas de campo como el Shuttle Run Test 20 metros (SRT-20m), el cual busca establecer el VO2max para cada sujeto, relacionando los valores obtenidos con aspectos como la composición corporal, edad y contexto poblacional, siendo una de las pruebas más confiables y con concordancia clínica existente. El propósito fue reconocer los cambios o variaciones presentes en los modelos matemáticos o lineales empleados en esta prueba con diferentes grupos poblacionales. Se realizó una revisión de la literatura bajo el marco básico para revisiones integradoras con algunas precisiones dadas por la guía PRISMA, identificando en su mayoría estudios de corte transversal los cuales evidencian los cambios realizados al planteamiento de la fórmula matemática donde las variables que inciden en el valor resultante para la resistencia aeróbica son: velocidad final, etapa de la prueba, edad y aspectos antropométricos del sujeto. Por lo anterior, se concluye que, para efectos prácticos, la estimación del VO2máx debe considerar factores intrínsecos del sujeto y aquellos relacionados con la ejecución de la prueba (AU)


For the evaluation of cardiorespiratory fitness, there are direct laboratory tests that provide objective information regarding this quality. However, when the resources are not available, the use of field tests such as the Shuttle Run Test 20 meters (SRT-20m) is used, which seeks to establish the VO2max for each subject, relating the values obtained with aspects such as body composition, age, and population context, being one of the most reliable tests with existing clinical agreement. The purpose was to recognize the changes or variations present in the mathematical or linear models used in this test with different population groups. A review of the literature was carried out under the basic framework for integrative reviews with some clarifications given by the PRISMA guide, identifying mostly cross-sectional studies which show the changes made to the approach of the mathematical formula where the variables that affect the resulting value for aerobic endurance are final speed, stage of the test, age, and anthropometric aspects of the subject. Therefore, it is concluded that, for practical purposes, the estimation of VO2max should consider intrinsic factors of the subject and those related to the execution of the test (AU)


Asunto(s)
Humanos , Consumo de Oxígeno/fisiología , Ventilación Voluntaria Máxima/fisiología , Pruebas Respiratorias , Modelos Biológicos
5.
Int J Mol Sci ; 24(19)2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37834186

RESUMEN

A family of acylhydrazones have been prepared and characterized with the aim of investigating their potential as information storage systems. Their well-established synthetic methodologies allowed for the preparation of seven chemically stable acylhydrazones in excellent yields that have been photophysically and photochemically characterized. In addition, DFT and TD-DFT calculations have been performed to gain more insights into the structural, energetic and photophysical properties of the E/Z isomers. Our results reveal that E/Z configurational isomerization upon irradiation is highly dependent on the stabilization of the E or Z isomers due to the formation of intramolecular H bonds and the electronic/steric effects intrinsically related to their structures. In addition, Raman spectroscopy is also used to confirm the molecular structural changes after the formation of hydrogen bonds in the isomers.


Asunto(s)
Espectrometría Raman , Modelos Moleculares , Isomerismo , Espectroscopía de Resonancia Magnética , Teoría Funcional de la Densidad
6.
Sci Total Environ ; 898: 165460, 2023 Nov 10.
Artículo en Inglés | MEDLINE | ID: mdl-37454851

RESUMEN

Assessment of microplastic (MP) contamination is still needed to evaluate this threat correctly and tackle this issue. Here, MP contamination was assessed for a meso-tidal lagoon of the Atlantic coast (Arcachon Bay, France). Sea surface, water column, intertidal sediments and wild oysters were sampled. Five different stations were studied to assess the spatial distribution of the contamination. Two were outside of the bay and three were inside the bay (from the inlet to the back). A distinction was made between all anthropogenic particles (AP, i.e. visually sorted) and MP (i.e. plastic polymer confirmed by ATR-FTIR spectroscopy). The length of particles recovered in this study ranged between 17 µm and 5 mm. Concentration and composition in sea surface and water column samples showed spatial variations while sediment and oyster samples did not. At outside stations, the sea surface and the water column presented a blended composition regarding shapes and polymers and low to high concentrations (e.g. 0.16 ± 0.08 MP.m-3 and 561.7 ± 68.5 MP.m-3, respectively for sea surface and water column), which can be due to coastal processes and nearby input sources. The inlet station displayed a well-marked pattern only at the sea surface. High AP and MP concentrations were recorded, and fragments along with polyethylene overwhelmed (respectively 76.0 % and 73.2 %). Higher surface currents could explain this pattern. At the bay back, AP and MP concentrations were lower and fibers were mainly recorded. Weaker hydrodynamics in this area was suspected to drive this contamination profile. Overall, fragments and buoyant particles were mainly detected at the sea surface while fibers and negatively buoyant particles prevailed in other compartments. Most of the studied samples presented an important contribution of fiber-shaped particles (from 31.5 % to 94.2 %). Finally, contamination was ubiquitous as AP and MP were found at all stations in all sample types.

7.
Environ Sci Technol ; 57(19): 7503-7515, 2023 05 16.
Artículo en Inglés | MEDLINE | ID: mdl-37125732

RESUMEN

Plastic is a widespread marine pollutant, with most studies focusing on the distribution of floating plastic debris at the sea surface. Recent evidence, however, indicates a significant presence of such low density plastic in the water column and at the seafloor, but information on its origin and dispersion is lacking. Here, we studied the pathways and fate of sinking plastic debris in the Mediterranean Sea, one of the most polluted world seas. We used a recent Lagrangian plastic-tracking model, forced with realistic parameters, including a maximum estimated sinking speed of 7.8 m/d. Our simulations showed that the locations where particles left the surface differed significantly from those where they reached the seafloor, with lateral transport distances between 119 and 282 km. Furthermore, 60% of particles deposited on the bottom coastal strip (20 km wide) were released from vessels, 20% from the facing country, and 20% from other countries. Theoretical considerations furthermore suggested that biological activities potentially responsible for the sinking of low density plastic occur throughout the water column. Our findings indicate that the responsibility for seafloor plastic pollution is shared among Mediterranean countries, with potential impact on pelagic and benthic biota.


Asunto(s)
Plásticos , Residuos , Mar Mediterráneo , Residuos/análisis , Monitoreo del Ambiente , Agua
8.
Allergy Asthma Immunol Res ; 15(2): 201-213, 2023 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37021506

RESUMEN

PURPOSE: Clavulanate, a beta-lactam associated with amoxicillin, is frequently prescribed in patients at all ages. Recent data implicate amoxicillin-clavulanate in up to 80% of beta-lactam allergy cases. We assessed clavulanate's role in inducing allergic reactions to this combination treatment, with a focus on selective immediate reactions. METHODS: Adults (≥ 16 years) reporting a history of immediate reactions to amoxicillin-clavulanate were evaluated through a beta-lactam allergological workup, using modified European Academy of Allergy and Clinical Immunology guidelines. Patients first underwent skin testing, and if negative, drug provocation tests. Expected outcomes were: Group A, subjects with immediate reaction to classical penicillin group determinants (penicilloyl polylysine, minor determinants mixture, and/or penicillin G); Group B, subjects with selective immediate reaction to amoxicillin; Group C, subjects with selective immediate reaction to clavulanate and Group D, those immediate reactions with co-sensitization to clavulanate plus penicillin group determinants or amoxicillin. RESULTS: Of 1,170 included patients, 104 had immediate reactions: 36.5% to penicillin group determinants (Group A), 26.9% to amoxicillin (Group B), 32.7% to clavulanate (Group C), and 3.8% to clavulanate plus penicillin determinants or amoxicillin (Group D). Diagnosis was made by skin testing in 79%, 75% and 47% of the patients, respectively, in the first 3 groups (P < 0.001). Drug provocation tests were necessary to establish most other diagnoses. Anaphylaxis predominated over urticaria/angioedema in all groups. CONCLUSIONS: Selective immediate reactions to clavulanate accounted for over a third of cases with confirmed reactions after amoxicillin-clavulanate intake, with more than half experiencing anaphylaxis. Within this group, skin test sensitivity was below 50%. People taking amoxicillin-clavulanate may also be co-sensitized to both drugs.

9.
Mar Pollut Bull ; 191: 114932, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37087826

RESUMEN

Monitoring the abundance and characteristics of microplastics in estuarine waters is crucial for understanding the fate of microplastics at the land-sea continuum, and for developing policies and legislation to mitigate associated risks. However, if protocols to monitor microplastic pollution in ocean waters or beach sediments are well established, they may not be adequate for estuarine environments, due to the complex 3D hydrodynamics. In this note, we review and discuss sampling methods and strategies in relation to the main environmental forcing, estuarine hydrodynamics, and their spatio-temporal scales of variability. We propose recommendations about when, where and how to sample microplastics to capture the most representative picture of microplastic pollution. This note opens discussions on the urgent need for standardized methods and protocols to routinely monitor microplastics in estuaries which should, at the same time, be easily adaptable to the different systems to ensure consistency and comparability of data across different studies.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Plásticos , Hidrodinámica , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Estuarios , Sedimentos Geológicos
11.
An. psicol ; 39(1): 51-61, Ene-Abr. 2023. tab, graf
Artículo en Inglés, Español | IBECS | ID: ibc-213838

RESUMEN

La premisa ampliamente aceptada de que el trabajo colaborati-vo entre los diferentes agentes de la comunidad educativa redunda en la mejora escolar y en mayores logros alcanzados por el alumnado no siempre se cumple debido a la realidad diversa que presentan los centros y a las di-ferentes iniciativas para impulsar la participación familiar. El estudio aborda la percepción que docentes, equipos directivos e inspección educativa tie-nen de las relaciones familia-escuela-comunidad en 23 centros de primaria de la Comunidad Autónoma Vasca, caracterizados por diferentes criterios de eficacia-ineficacia escolar, con la finalidad de identificar buenas prácticas que contribuyan a la mejora escolar. Se trata de un estudio descriptivo-exploratorio-explicativo de metodología mixta, con empleo de cuestiona-rios, entrevistas en profundidad y grupos de discusión. Los resultados muestran que la implicación familiar está mediatizada por factores persona-les del profesorado, que todos los centros tratan de impulsar la colabora-ción familiar, aunque las formas y acciones de participación varían, y que aquellos que mejor funcionan tienen una actitud proactiva, con énfasis en dimensiones diferentes de colaboración. Entre las conclusiones cabe desta-car la adopción de un enfoque sistémico, la revisión y actualización de las modalidades formativas, y la evaluación de las competencias docentes para la colaboración.(AU)


The commonly accepted premise that collaboration among the educational community leads to school improvement and greater student achievement is not always fulfilled due to the diverse reality of schools and various initiatives to promote family participation. This work addresses the perception of teachers, school management teams and educational inspec-tion of family-school-community relations in 23 primary schools in the Basque Autonomous Community, characterized by different criteria related to school effectiveness-ineffectiveness, aiming to identify good practice leading to school improvement. The study is descriptive-exploratory-exploratory-explanatory with mixed methodology, using questionnaires, in-depth interviews and discussion groups. Results show family involvement is mediated by teaching staff ́s personal factors, that all schools try to pro-mote family collaboration, though forms of participation vary, and those which work best are proactive, stressing different collaboration dimen-sions. Conclusions include adopting a systemic approach, review and up-dating of training modalities, and assessment of teaching competences for collaboration.(AU)


Asunto(s)
Humanos , Masculino , Femenino , Maestros , Relaciones Familiares , Rendimiento Académico , Educación Primaria y Secundaria , Psicología , Psicología Clínica , Psicología Social
12.
Rev. colomb. cir ; 38(1): 154-165, 20221230. tab, fig
Artículo en Español | LILACS | ID: biblio-1415992

RESUMEN

Introducción. La obstrucción intestinal es una patología de alta prevalencia. Su abordaje diagnóstico y terapéutico ha evolucionado acorde con el avance del conocimiento e implementación de la tecnología. El impacto de sus complicaciones obliga a redoblar esfuerzos en pro de lograr una mayor efectividad. Se hizo una aproximación reflexiva al problema, mediante una identificación de los puntos controversiales de interés para el cirujano general. Métodos. Se realizó una búsqueda sistemática de la literatura en varias bases de datos, utilizando dos ecuaciones de búsqueda que emplearon términos seleccionados a partir de los tesauros "Medical Subject Heading" (MeSH) y "Descriptores en Ciencias de la Salud" (DeCS). Resultados. Se recolectaron 43 artículos y a partir de ellos se construyó el texto de revisión. La identificación pronta de los posibles candidatos a cirugía, mediante un esquema diagnóstico y terapéutico, se constituye en una prioridad en el manejo de estos pacientes. De igual manera, se efectúan consideraciones en la toma de decisiones con respecto a la vía quirúrgica, así como recomendaciones técnicas operatorias producto de la experiencia y lo reportado en la literatura. Existen factores propios del cirujano, del contexto y del paciente, que inciden en la resolución del problema. Conclusión. La obstrucción intestinal y sus implicaciones clínicas obligan a una reevaluación constante de su estado del arte y avances en el manejo, tendiente a una búsqueda de oportunidades para impactar favorablemente en su curso clínico. Hay estrategias por implementar, inclusive el manejo laparoscópico en casos seleccionados


Introduction. Intestinal obstruction is a pathology of high prevalence. Its diagnostic and therapeutic approach has evolved according to the progress in knowledge and implementation of technology. The impact of its complications makes it necessary to make the efforts to achieve higher effectiveness. A reflexive approach to the problem is made by identifying the controversial points of interest for the general surgeon. Methods. A systematic literature search was carried out in several databases, using two search equations from the review performed in the thesaurus "Medical Subject Heading" (MeSH) and "Descriptors in Health Sciences" (DeCS). Results. A total of 43 articles were collected using the selected methods and the review text was constructed from them. The early identification of possible candidates for surgery, by means of a diagnostic and therapeutic algorithm, is a priority in the management of these patients. Likewise, considerations are made in decision-making regarding the laparoscopic vs. traditional approach, as well as operative technical recommendations based on experience and what has been reported in the literature. There are factors specific to the surgeon, the context and the patient that influence the resolution of the problem. Conclusion. Intestinal obstruction and its clinical implications require a constant reevaluation of the state of the art and advances in management, tending to search for opportunities to favorably impact its clinical course. There are strategies to be implemented, including laparoscopic management in selected cases


Asunto(s)
Humanos , Adherencias Tisulares , Obstrucción Intestinal , Laparoscopía , Tratamiento Conservador , Isquemia , Antiinflamatorios
13.
J Asthma Allergy ; 15: 1359-1367, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36189188

RESUMEN

Background: Allergy can start at early ages, with genetic and environmental factors contributing to its development. Aim: The study aimed to describe the pattern of sensitisation and allergy in children and adolescents of Spanish versus Moroccan ancestry but born in the same rural area of Spain. Methods: Participants were children and adolescents (3-19 years) of Spanish or Moroccan descent, born in Blanca, Murcia (Spain). A detailed questionnaire was completed, and skin prick tests were performed to assess reactions to the most prevalent pollen allergens (O. europaea, P. pratense, S. kali, C. arizonica, P. acerifolia, A. vulgaris and P. judaica) plus molecular components Ole e 1 and Ole e 7. The association with ancestry was verified by studying participants' parents. Results: The study included 693 participants: 48% were aged 3-9 years and 52%, 10-19 years; 80% were of Spanish descent and 20% of Moroccan descent. Sensitisation to Olea europaea, Phleum pratense, Salsola kali and Cupressus arizonica were slightly higher in the Spanish group. The only significant differences were observed in sensitisation to Ole e 1 (p=0.02). Rhinitis, conjunctivitis, and rhinitis plus asthma were significantly higher in the Spanish group (p=0.03, p=0.02, p=0.007, respectively). The sensitisation pattern differed between Spanish and Moroccan parents, and between Moroccan parents and their children, but not between Spanish parents and their children. Conclusion: Both environment and ancestry may influence sensitisation and symptoms. Although the environment seems to have a stronger influence, other factors may contribute to the differences in prevalence and in the clinical entities in people of Spanish versus Moroccan descent.

14.
Biology (Basel) ; 11(10)2022 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-36290322

RESUMEN

Disrupted circadian cycle has been reported in multiple sclerosis (MS). Previous genome-wide association studies (GWAS) singled out over 230 variants associated with MS. A study performed in a Slavic population identified two new single nucleotide polymorphisms (SNPs), rs6811520 (CLOCK) and rs3789327 (ARNTL/BMAL1), associated with MS risk. However, these regions that codify the capital regulators of circadian rhythm had not been linked to the disease before, so replication in independent populations is warranted to ascertain possible geographical differences. Our aim was to replicate the associations reported in the ARNTL/BMAL1 and CLOCK genes in a Spanish cohort with a maximum of 974 MS patients and 626 controls. In this study, 956 MS patients and 612 controls were successfully genotyped for rs6811520 and 943 MS patients and 598 controls for rs3789327.Clinical variables (age at disease onset, EDSS, or relapses) were collected in a maximum of 549 patients. No statistically significant differences were found between cases and controls for the analyzed SNPs, even after stratifications by sex, clinical form, or HLA-DRB1*15:01 status. No influence of the SNPs was found on age at disease onset, EDSS, or annual relapse rate at 5 years after onset. In conclusion, our study does not replicate the associations observed in the previously investigated Slavic population.

15.
Pediatr Blood Cancer ; 69(10): e29790, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-35670754

RESUMEN

Colorectal cancer in the pediatric population is a rare but transpirable phenomenon. The occurrence should prompt suspicion for underlying genetic mutations in the setting of a hereditary cancer predisposition syndrome. In this series, we outline three pediatric patients with colonic adenocarcinoma who were found to have one or more germline mutations. The presence of compound mutations may lead to a hypermutator phenotype resulting in earlier presentation of colorectal cancer in childhood and adolescence. The diagnosis of colorectal cancer in pediatric patients warrants timely recognition, multigene panel testing, genetic counseling for the patient and family, and increased surveillance for intestinal and extra-intestinal tumors.


Asunto(s)
Neoplasias Colorrectales , Síndromes Neoplásicos Hereditarios , Edad de Inicio , Niño , Neoplasias Colorrectales/diagnóstico , Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad , Pruebas Genéticas/métodos , Mutación de Línea Germinal , Humanos , Síndromes Neoplásicos Hereditarios/genética , Fenotipo
16.
Nat Commun ; 13(1): 2981, 2022 05 27.
Artículo en Inglés | MEDLINE | ID: mdl-35624104

RESUMEN

Plastic debris is a ubiquitous pollutant on the sea surface. To date, substantial research efforts focused on the detection of plastic accumulation zones. Here, a different paradigm is proposed: looking for crossroad regions through which large amounts of plastic debris flow. This approach is applied to the Mediterranean Sea, massively polluted but lacking in zones of high plastic concentration. The most extensive dataset of plastic measurements in this region to date is combined with an advanced numerical plastic-tracking model. Around 20% of Mediterranean plastic debris released every year passed through about 1% of the basin surface. The most important crossroads intercepted plastic debris from multiple sources, which had often traveled long distances. The detection of these spots could foster understanding of plastic transport and help mitigation strategies. Moreover, the general applicability and the soundness of the crossroad approach can promote its application to the study of other pollutants.


Asunto(s)
Contaminantes Ambientales , Plásticos , Monitoreo del Ambiente , Mar Mediterráneo , Residuos/análisis
17.
Environ Sci Technol ; 56(12): 8114-8123, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35593651

RESUMEN

Vertical dynamics of microplastics (MPs) in the water column are complex and not fully understood due to the diversity of environmental MPs and the impact of weathering and biofouling on their dynamical properties. In this study, we investigate the effects of the particle properties and biofilm on the vertical (settling or rising) velocity of microplastic sheets and fibers under laboratory conditions. The experiments focus on three types of MPs (polyester PES fibers, polyethylene terephthalate PET sheets, and polypropylene PP sheets) of nine sizes and two degrees of biological colonization. Even though pristine PES fibers and PET sheets had a similar density, the sinking velocity of fibers was much smaller and independent of their length. The settling or rising velocity of sheets increased with the particle size up to a threshold and then decreased in the wake of horizontal oscillations in large particles. Biofilms had unexpected effects on vertical velocities. Irregular biofilm distributions can trigger motion instabilities that decrease settling velocities of sheets despite the increase in density. Biofilms can also modify the orientation of fibers, which may increase their settling velocity. Finally, we selected the most performant theoretical formulation for each type of particle and proposed modifications to consider the effect of biofilm distribution.


Asunto(s)
Incrustaciones Biológicas , Contaminantes Químicos del Agua , Biopelículas , Monitoreo del Ambiente , Microplásticos , Plásticos , Contaminantes Químicos del Agua/análisis
18.
Conserv Biol ; 36(1): e13834, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34476838

RESUMEN

From a conservation perspective, quantifying potential refugial capacity has been predominantly focused on climate refugia, which is critical for maintaining the persistence of species and ecosystems. However, protection from other stressors, such as human-induced changes in fire and hydrology, that cause habitat loss, degradation, and fragmentation is also necessary to ensure that conservation efforts focused on climate are not undermined by other threats. Thus, conceptual and methodological advances for quantifying potential refugia from multiple anthropogenic stressors are important to support conservation efforts. We devised a new conceptual approach, the domains of refugia, for assessing refugial capacity that identifies areas where exposure to multiple stressors is low. In our framework, patterns of environmental variability (e.g., increased frequency of warm summers), thresholds of resilience, and extent and intensity of stressors are used to identify areas of potential refugia from a suite of ongoing anthropogenic stressors (e.g., changes in fire regime). To demonstrate its utility, we applied the framework to a Southern California landscape. Sites with high refugial capacity (super-refugia sites) had on average 30% fewer extremely warm summers, 20% fewer fire events, 10% less exposure to altered river channels and riparian areas, and 50% fewer recreational trails than the surrounding landscape. Our results suggest that super-refugia sites (∼8200 km2 ) for some natural communities are underrepresented in the existing protected area network, a finding that can inform efforts to expand protected areas. Our case study highlights how considering exposure to multiple stressors can inform planning and practice to conserve biodiversity in a changing world.


Marco Conceptual a para Identificar Refugios de Múltiples Amenazas a Escala de Paisaje Resumen Desde la perspectiva de la conservación, la cuantificación de la capacidad potencial de refugio se ha enfocado principalmente en los refugios climáticos, los cuales son críticos para mantener la persistencia de las especies y los ecosistemas. Sin embargo, la protección ante otros factores estresantes, como los cambios inducidos por los humanos en los incendios y la hidrología, que causan la pérdida, degradación y fragmentación del hábitat, también son necesarios para asegurar que los esfuerzos de conservación enfocados en el clima no sean afectados por otras amenazas. Por lo tanto, los avances conceptuales y metodológicos para cuantificar los refugios potenciales ante múltiples factores estresantes causados por el humano son importantes para asegurar que los esfuerzos de conservación logren sus objetivos. Diseñamos una nueva estrategia conceptual, los dominios de los refugios, para evaluar la capacidad de refugio de un paisaje donde la exposición a múltiples factores estresantes es baja. En nuestro marco conceptual usamos los patrones de variabilidad ambiental (p. ej.: incremento en la frecuencia de veranos cálidos), los umbrales de resiliencia y la extensión e intensidad de los factores estresantes para identificar las áreas de refugios potenciales a partir de un conjunto de factores antropogénicos persistentes (p. ej.: cambios en el régimen de incendios). Para demostrar su utilidad, aplicamos el marco conceptual a un paisaje del sur de California. Los sitios con una alta capacidad de refugio (sitios de súper-refugios) tuvieron en promedio un 30% menos veranos extremadamente cálidos, 20% menos eventos de incendios y 50% menos senderos recreativos que el paisaje circundante. Nuestros resultados sugieren que los sitios de súper-refugios (∼ 8,200 km2 ) para algunas comunidades naturales están subrepresentados en la red existente de áreas protegidas, un resultado que puede orientar los esfuerzos por expandir las áreas protegidas. Nuestro estudio de caso resalta que considerar la exposición a múltiples amenazas puede guiar la planificación y la práctica de la conservación de la biodiversidad en un mundo cambiante.


Asunto(s)
Ecosistema , Refugio de Fauna , Biodiversidad , Cambio Climático , Conservación de los Recursos Naturales/métodos , Humanos
19.
Artículo en Inglés | MEDLINE | ID: mdl-36612474

RESUMEN

The academic curriculum has shown to promote sedentary behavior in college students. This study aimed to profile the physical fitness of physical education majors using unsupervised machine learning and to identify the differences between sexes, academic years, socioeconomic strata, and the generated profiles. A total of 542 healthy and physically active students (445 males, 97 females; 19.8 [2.2] years; 66.0 [10.3] kg; 169.5 [7.8] cm) participated in this cross-sectional study. Their indirect VO2max (Cooper and Shuttle-Run 20 m tests), lower-limb power (horizontal jump), sprint (30 m), agility (shuttle run), and flexibility (sit-and-reach) were assessed. The participants were profiled using clustering algorithms after setting the optimal number of clusters through an internal validation using R packages. Non-parametric tests were used to identify the differences (p < 0.05). The higher percentage of the population were freshmen (51.4%) and middle-income (64.0%) students. Seniors and juniors showed a better physical fitness than first-year students. No significant differences were found between their socioeconomic strata (p > 0.05). Two profiles were identified using hierarchical clustering (Cluster 1 = 318 vs. Cluster 2 = 224). The matching analysis revealed that physical fitness explained the variation in the data, with Cluster 2 as a sex-independent and more physically fit group. All variables differed significantly between the sexes (except the body mass index [p = 0.218]) and the generated profiles (except stature [p = 0.559] and flexibility [p = 0.115]). A multidimensional analysis showed that the body mass, cardiorespiratory fitness, and agility contributed the most to the data variation so that they can be used as profiling variables. This profiling method accurately identified the relevant variables to reinforce exercise recommendations in a low physical performance and overweight majors.


Asunto(s)
Educación y Entrenamiento Físico , Aprendizaje Automático no Supervisado , Masculino , Femenino , Humanos , Estudios Transversales , Aptitud Física , Ejercicio Físico , Índice de Masa Corporal
20.
Sci Total Environ ; 797: 149144, 2021 Nov 25.
Artículo en Inglés | MEDLINE | ID: mdl-34346359

RESUMEN

Coastal environments are a predominant ultimate destination of marine debris, becoming a key focus of studies assessing microplastic (MP) contamination. Here, we described the visible fraction of MP (from 0.5 to 5 mm) that washed up during the high tide at different sites of a semi-enclosed mesotidal bay and investigated the main abiotic factors driving MP beaching. Three contrasted beaches of the Arcachon Bay (SW France) were monitored on a monthly basis during 2019. Samplings were made along a 100 m longitudinal transect at the high-water strandline (4 quadrats of 0.25m2) and at an intermediate tidal range. Each sampled particle was characterized by morphometric data (e.g. size, shape, color, roughness) and polymer identification was performed by ATR-FTIR technique. Results show that MP concentration was higher on the beach located at the mouth of the bay (36.0 ± 39.2 MP.m-2) than at the back and the outside of the bay (respectively 2.7 ± 4.4 and 1.7 ± 2.4 MP.m-2). This may be related to the strong currents at the entry of the embayment and the beach orientation, exposed to predominant winds. Beached MP were mainly pre-production pellets and fragments as they represented respectively 49% and 39% of all analyzed shapes. Polymers with low density were particularly abundant. Polyethylene represented 69% of all the particles while polypropylene accounted for 17% and polystyrene for 10%. We also observed that MP were mostly washed up when wind, waves and river flow were more intense. Analysis suggest that wind direction and speed are key factors influencing beaching as strong onshore wind enhance this process.


Asunto(s)
Microplásticos , Contaminantes Químicos del Agua , Monitoreo del Ambiente , Francia , Plásticos , Ríos , Contaminantes Químicos del Agua/análisis
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