Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 67
Filtrar
1.
Sci Total Environ ; 948: 174791, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39019291

RESUMO

The Patos Lagoon estuary is a highly significant ecosystem where freshwater from a vast and densely populated area continuously flows into the Atlantic Ocean by coastal plumes, exporting not only freshwater but also sediment, nutrients, plastics, and other contaminants. In this work, numerical modeling tools together with field data were used to assess for the first time the capacity of the coastal plume to export microplastics (MPs) to the inner shelf under different hydrodynamic conditions. Two field surveys were conducted during plume events to quantify MP concentrations and validate the model approach. A bottom-up approach was employed to estimate the potential MP export from the estuary's domain to the Atlantic Ocean. MP concentration in surface plume waters ranged from 0.20 items m-3 to 1.37 items m-3, confirmed by FTIR as synthetic polymers in a 90 %, being Polypropylene (PP) and Polyethylene (PE) the most abundant in a 73 %. The accumulation pattern was observed on the plume's frontal system, consistent with simulation results. The estimated average MP potential export rate attained 9.0 million items day-1 during moderate plume events and 47.5 million items day-1 during high discharge plume events. Strong discharge events, coupled with intense northeast winds, facilitated rapid southwestward export of MPs. Conversely, moderate to weak discharge events retained MPs closer to the estuary's mouth, enabling either longer trajectories or earlier deposition. Significant MP accumulation hotspots were identified in the gyre between the jetties and Cassino beach, as well as in the saline front within the plume boundaries. These accumulation zones may function as reservoirs for MP particles, potentially posing threats to local ecosystems. Understanding these dynamics is crucial for ongoing monitoring efforts to assess potential harmful interactions over time.

2.
J Pediatr Gastroenterol Nutr ; 79(1): 161-167, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38801072

RESUMO

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) 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.


Assuntos
Receptores de Proteínas Morfogenéticas Ósseas Tipo I , Polipose Intestinal , Mutação , Síndromes Neoplásicas Hereditárias , Fenótipo , Proteína Smad4 , Humanos , Proteína Smad4/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo I/genética , Criança , Masculino , Feminino , Polipose Intestinal/genética , Polipose Intestinal/congênito , Adolescente , Síndromes Neoplásicas Hereditárias/genética , Pré-Escolar , Seguimentos
3.
JPGN Rep ; 5(2): 170-174, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38756112

RESUMO

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.

4.
Rev. colomb. cir ; 39(2): 299-307, 20240220. tab
Artigo em Espanhol | LILACS | ID: biblio-1532686

RESUMO

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.


Assuntos
Humanos , Programas de Rastreamento , Aneurisma da Aorta Abdominal , Angiografia por Tomografia Computadorizada , Doenças da Aorta , Tabagismo , Ultrassonografia
5.
Int J Mol Sci ; 24(19)2023 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-37834186

RESUMO

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.


Assuntos
Análise Espectral Raman , Modelos Moleculares , Isomerismo , Espectroscopia de Ressonância Magnética , Teoria da Densidade Funcional
6.
Sci Total Environ ; 898: 165460, 2023 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-37454851

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-37125732

RESUMO

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.


Assuntos
Plásticos , Resíduos , Mar Mediterrâneo , Resíduos/análise , Monitoramento Ambiental , Água
8.
Allergy Asthma Immunol Res ; 15(2): 201-213, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37021506

RESUMO

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.
Artigo em Inglês | MEDLINE | ID: mdl-37087826

RESUMO

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.


Assuntos
Microplásticos , Poluentes Químicos da Água , Plásticos , Hidrodinâmica , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Estuários , Sedimentos Geológicos
10.
Rev. colomb. cir ; 38(1): 154-165, 20221230. tab, fig
Artigo em Espanhol | LILACS | ID: biblio-1415992

RESUMO

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


Assuntos
Humanos , Aderências Teciduais , Obstrução Intestinal , Laparoscopia , Tratamento Conservador , Isquemia , Anti-Inflamatórios
11.
J Asthma Allergy ; 15: 1359-1367, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36189188

RESUMO

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.

12.
Biology (Basel) ; 11(10)2022 Sep 28.
Artigo em Inglês | MEDLINE | ID: mdl-36290322

RESUMO

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.

13.
Pediatr Blood Cancer ; 69(10): e29790, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35670754

RESUMO

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.


Assuntos
Neoplasias Colorretais , Síndromes Neoplásicas Hereditárias , Idade de Início , Criança , Neoplasias Colorretais/diagnóstico , Neoplasias Colorretais/genética , Predisposição Genética para Doença , Testes Genéticos/métodos , Mutação em Linhagem Germinativa , Humanos , Síndromes Neoplásicas Hereditárias/genética , Fenótipo
14.
Nat Commun ; 13(1): 2981, 2022 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-35624104

RESUMO

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.


Assuntos
Poluentes Ambientais , Plásticos , Monitoramento Ambiental , Mar Mediterrâneo , Resíduos/análise
15.
Environ Sci Technol ; 56(12): 8114-8123, 2022 06 21.
Artigo em Inglês | MEDLINE | ID: mdl-35593651

RESUMO

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.


Assuntos
Incrustação Biológica , Poluentes Químicos da Água , Biofilmes , Monitoramento Ambiental , Microplásticos , Plásticos , Poluentes Químicos da Água/análise
16.
Conserv Biol ; 36(1): e13834, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34476838

RESUMO

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.


Assuntos
Ecossistema , Refúgio de Vida Selvagem , Biodiversidade , Mudança Climática , Conservação dos Recursos Naturais/métodos , Humanos
17.
Artigo em Inglês | MEDLINE | ID: mdl-36612474

RESUMO

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.


Assuntos
Educação Física e Treinamento , Aprendizado de Máquina não Supervisionado , Masculino , Feminino , Humanos , Estudos Transversais , Aptidão Física , Exercício Físico , Índice de Massa Corporal
18.
Sci Total Environ ; 797: 149144, 2021 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-34346359

RESUMO

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.


Assuntos
Microplásticos , Poluentes Químicos da Água , Monitoramento Ambiental , França , Plásticos , Rios , Poluentes Químicos da Água/análise
19.
Pediatr Allergy Immunol ; 32(8): 1788-1795, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34324747

RESUMO

BACKGROUND: Beta-lactams generate different allergenic determinants that induce selective or cross-reactive drug hypersensitivity reactions (DHRs). We aimed to identify the drugs involved, the selectivity of the response, the mechanism, and the value of the different diagnostic tests for establishing a diagnosis in children evaluated for DHRs to beta-lactams. METHODS: Prospective study evaluating children aged under 16 years reporting DHRs to beta-lactams. Reactions were classified as immediate and non-immediate reactions. The workup included sIgE, skin testing, and drug provocation tests (DPTs) for immediate reactions and patch testing and DPTs for non-immediate ones. RESULTS: Of the 510 children included, 133 were evaluated for immediate reactions and confirmed in 8.3%. Skin test/in vitro IgE contributed to diagnosing half of the cases. Selective reactions occurred with amoxicillin (63%), followed by common penicillin determinants (27%) and cephalosporins (0.9%). Among non-immediate reactions (11.4% of the 377 children evaluated), most required DPTs, 52.7% of which were positive at 6-7 days of drug challenge. Selective reactions were identified with amoxicillin (80%), penicillin G (7.5%), cephalosporins (7.5%), and clavulanic acid (5%). Urticaria and maculopapular exanthema were the most frequent entities. CONCLUSIONS: There were few confirmed cases of either type of reaction. Skin testing proved less valuable in non-immediate reactions, over half of which would also have been lost in a short DPT protocol. Selective responders to amoxicillin were more likely to have non-immediate reactions, while clavulanic acid selectivity was exclusive to the non-immediate typology. Over half the cases with DPTs required 6-7 days of treatment for DHR confirmation.


Assuntos
Hipersensibilidade a Drogas , Hipersensibilidade Imediata , Preparações Farmacêuticas , Antibacterianos/efeitos adversos , Criança , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/epidemiologia , Humanos , Estudos Prospectivos , Testes Cutâneos , beta-Lactamas/efeitos adversos
20.
Front Public Health ; 9: 683655, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249846

RESUMO

Background: Cardiovascular disease is becoming increasingly prevalent in low and middle-income countries (LMIC), and high blood pressure (BP) is one of the main risk factors. The efficacy and sustainability of worksite health promotion (WHP) programs for BP reduction in LMIC have yet to be determined. Methods: This non-randomized company-based trial evaluated 6- and 12-months effects of a WHP intervention on BP among 2,002 participating workers from seven Mexican companies. Intervention and control groups were assigned at the company level. The intervention included nutrition counseling, physical exercise, and stress management components. Mixed models assessed differences in BP change between intervention and control companies in intent-to-treat (ITT), per-protocol (PerP), and as-treated (AsTr) analyses, and also within-group changes stratified by company, intervention component, and baseline cardiovascular risk factor levels. All analyses were adjusted for potential confounders. We accounted for missing data and loss to follow-up using inverse probability of censoring weighting. Results: ITT analyses revealed mean BP change differences of -1.1 mmHg at 12 months (95% CI: -2.9; 0.6) in intervention companies relative to control companies. PerP and AsTr analyses confirmed this finding. Within-group analyses showed consistent BP reductions at both 6 and 12 months. Substantial differences in BP changes ranging from diastolic -6.1 mmHg, (95% CI: -11.2; -1.2) to systolic -13.0 mmHg (95% CI: -16.0; -10.1) were found among individuals with diabetes at baseline in intervention companies relative to control companies. Conclusion: After 1 year, WHP was associated with modest but uncertain BP reductions. Substantial reductions were mainly observed among diabetic workers.


Assuntos
Doenças Cardiovasculares , Hipertensão , Pressão Sanguínea , Doenças Cardiovasculares/epidemiologia , Exercício Físico , Promoção da Saúde , Humanos , Hipertensão/epidemiologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA