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1.
Environ Monit Assess ; 195(11): 1316, 2023 Oct 14.
Artigo em Inglês | MEDLINE | ID: mdl-37833421

RESUMO

Estuaries are the main entry areas of mercury to the marine environment and are important to understand the effect of this contaminant on marine organisms, since it accumulates in the sediments becoming available to enter the food trophic chain. This study aims to determine the environmental variables that mainly influence the spatiotemporal dynamics of total mercury accumulation in sediments of tropical estuaries. Sediment samples were collected from interior and exterior areas of the estuary during the dry and rainy seasons, representing the spatiotemporal gradients of the estuary. The grain size, organic matter content (OM), and total mercury concentration (THg) of the sediment samples were determined. In addition, salinity, temperature, dissolved oxygen, and pH of the water column associated with each sediment sample were assessed. The variations in environmental conditions, OM and THg in sediment were in accordance with a gradient which goes from conditions influenced by fresh water in the inner estuary to conditions influenced by sea water in the outer part of the estuary. The OM and THg in sediments presented similar variation patterns; they were higher in the rainy season than in the dry season and in the interior area of the estuary than in the exterior area. Despite the complex dynamic observed in the distribution and accumulation processes of mercury in sediments, these processes could be modeled from OM and salinity parameters. Due to the correlations found, in the process of accumulation of mercury in sediments the OM could represents the pathway of transport and accumulation of THg, and salinity could represent the influence of the hydroclimatic variations and environmental gradients of the estuary.


Assuntos
Mercúrio , Poluentes Químicos da Água , Estuários , Monitoramento Ambiental , Baías , Mercúrio/análise , Colômbia , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química
2.
Environ Monit Assess ; 194(10): 720, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-36056178

RESUMO

Tropical estuaries are productive dynamic ecosystems where water quality is mediated by physicochemical and biological processes and by fluvial and anthropogenic discharges. The objective of the study was to determine the influence of environmental variables on the spatiotemporal dynamics of water quality in Buenaventura Bay, which is a highly impacted estuary. Sampling was carried out during the dry and rainy season, at three depths, in four stations that represent the environmental gradient of the bay. Temperature, total dissolved solids, salinity, dissolved oxygen, and pH were determined for each sample. In addition, alkalinity, phosphates, nitrites, and nitrates as indicators of water quality were also measured. The estuary was classified as meso- and polyhaline, with appropriate oxygen and pH conditions and spatiotemporal gradients of temperature and solids mediated by river discharges. Significant variations were found in the physicochemical variables by season, with maximum salinity, pH, and solids in the dry season and oxygen and temperature in the rainy season. Likewise, most of these environmental variables were higher in the outer zone of the estuary and lower in the inner stations. Alkalinity and nitrite values were within the permitted ranges, while phosphates and nitrates indicated low water quality. There was a significant direct influence of temperature and oxygen on alkalinity and nitrites. However, for phosphates, no significant influence of environmental variables was found, suggesting a greater influence by fluvial and anthropogenic discharges, which produce a decrease in the environmental quality of the estuary.


Assuntos
Nitritos , Qualidade da Água , Baías , Colômbia , Ecossistema , Monitoramento Ambiental , Estuários , Nitratos/análise , Nitritos/análise , Compostos Orgânicos , Oxigênio/análise , Fosfatos/análise , Rios , Estações do Ano
3.
Integr Environ Assess Manag ; 18(3): 796-812, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-34524737

RESUMO

The anthropogenic discharges of inorganic nutrients impact water quality, affecting the macroinvertebrate assemblage and food safety. The main objective of this study was to examine the seawater quality and macroinvertebrate dynamics in muddy habitats of Buenaventura Bay, Colombian Pacific. Macroinvertebrates were captured using artisanal trawl nets during different seasons and along four sampling sites. Multivariate analyses (canonical correspondence analysis and generalized additive model) were used to assess the effects of variations in nitrite, nitrates, phosphate concentrations, and physicochemical variables (salinity, pH, dissolved oxygen [DO], temperature, and total dissolved solids [TDS]) of water on the macroinvertebrate assemblage. Richness was the highest at sites with high salinity and temperature and low concentrations of nitrites and TDS. The densities of the commercial shrimp species Xiphopenaeus riveti and Rimapenaeus byrdi were the highest at sites with higher DO and alkalinity, and lower nitrate concentrations. The swimming crab Callinectes arcuatus was dominant at sites with low water quality. In summary, in the transitional season and at the inner sites of Buenaventura Bay, it was observed the lowest water quality due to high nitrate concentration. High nitrate concentration was highlighted as the main anthropogenic factor that could decrease the capture of target macroinvertebrate species for food and livelihoods of artisanal fishermen and their families. Thus, macroinvertebrate communities may be vulnerable to increased inorganic nutrient inputs, which could affect estuarine water quality and ecosystems services. Integr Environ Assess Manag 2022;18:796-812. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).


Assuntos
Estuários , Qualidade da Água , Animais , Baías , Ecossistema , Monitoramento Ambiental , Humanos , Invertebrados , Nitratos , Rios
4.
Rev. biol. trop ; 69(3)sept. 2021.
Artigo em Espanhol | LILACS, SaludCR | ID: biblio-1387674

RESUMO

Resumen Introducción: La dinámica de las condiciones ambientales influencia la variación del alimento disponible para los organismos estuarinos, afectando el consumo de alimento de los organismos bentónicos como los lenguados, esenciales para establecer y monitorear la calidad ambiental en estos ecosistemas. Objetivo: Determinar los hábitos tróficos de tres especies de la familia Achiridae en la Bahía de Buenaventura, Pacífico colombiano. Métodos: Los peces se recolectaron por medio de pesca de arrastre artesanal. Así mismo, en laboratorio se determinó la dieta de cada una de las especies y se calcularon diferentes índices tróficos, registrando diferencias en los hábitos alimentarios entre estas especies. Resultados: Se recolectó un total de 159 peces del género Achirus, siendo la especie más abundante Achirus klunzingeri (98), luego Achirus mazatlanus (44) y finalmente Achirus scutum (17). La dieta de A. scutum se basó en detritos, la de A. mazatlanus en detritos y peces y la de A. klunzingeri en crustáceos y peces. Los individuos de A. klunzingeri presentaron diferencias en su dieta entre la zona interna y externa del estuario, en la zona interna los peces fueron la presa principal y en la zona externa fueron los crustáceos. Las especies A. klunzingeri y A. mazatlanus presentaron ingesta de microplásticos, principalmente fibras alargadas e incoloras presentes en individuos de todas las tallas. La dinámica de los hábitos tróficos de A. klunzingeri, se relacionaron con algunas variables ambientales, como temperatura, trasparencia y oxígeno disuelto. Por ejemplo, estas tres variables presentaron correlaciones negativas con el ítem peces, y positivas para la categoría crustáceos. Conclusión: Se evidenció que estas especies son generalistas y que las condiciones ambientales no solo influenciaron la dinámica del consumo alimentario, sino que también, determinaron la presencia de los microplásticos.


Abstract Introduction: The dynamic of the environmental conditions influences the availability of the food resources for the estuarine organisms, affecting the food consumption of the benthic organism such as the soles, which are essential for establishing and monitoring the environmental quality of these ecosystems. Objective: To determine the trophic habits of three species of the Achiridae family in Buenaventura Bay, Colombian Pacific. Methods: Fish were captured using artisanal trawling. Then, the diet of each species was determined and different trophic indexes were calculated registering differences in alimentary habits among species. Results: It was collected a total of 159 fishes of the genus Achirus, being the most abundant Achirus klunzingeri (98), then Achirus mazatlanus (44) and finally Achirus scutum (17). The diet of A. scutum was based on detritus, the diet of A. mazatlanus was mainly detritus and fish whereas the diet of A. klunzingeri presented a dynamic pattern based mainly on crustaceans and fish. The individuals of Achirus klunzingeri presented differences in the diet between the internal and external area of the estuary, in the internal zone the fish were the main prey while in the external zone were the crustaceans. The species A. klunzingeri and A. mazatlanus presented ingestion of microplastics, mainly elongated and colorless fibers which were present in individuals of all sizes. The dynamic of the trophic habits of A. klunzingeri was related to the environmental variables such as temperature, transparency and dissolved oxygen. For example, these three variables presented negative correlations with the item fishes, and positive for the crustacean category. Conclusions: Despite the generalist nature of the studied species, the environmental conditions, not only influenced the food consumption dynamic, but also determined the presence of microplastics.


Assuntos
Animais , Estuários , Crustáceos , Peixes
5.
Pediatr Transplant ; 25(7): e14082, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34255405

RESUMO

INTRODUCTION: The only curative treatment for severe aplastic anemia in children is an allogeneic stem cell transplant; however, few patients have a matched related or unrelated donor. Haploidentical stem cell transplantation (haplo-SCT) using bone marrow (BM) and peripheral blood stem cells (PBSC) has been recently described as effective and safe. In this study, we retrospectively report the outcome of twelve pediatric patients who underwent haplo-SCT using only PBSC. METHODS: The conditioning regimen consisted on rabbit anti-thymocyte globulin (r-ATG) 2.5 mg/kg/d on days -7, -6,-5, and -4, and cyclophosphamide (Cy) 50 mg/kg/d on days -3 and -2. We used Cy 50 mg/kg/d on days +3 and +4, tacrolimus and mycophenolic acid as graft versus host disease (GVHD) prophylaxis. RESULTS: The median follow-up was 1,099 days (45-1258 days). The overall survival rate up-to-date is 83.3%. In 10 of the 12 patients, a sustained graft was achieved. None of the patients had acute or chronic GVHD. CONCLUSIONS: Haplo-SCT could be established as a first-line treatment when there is no matched related or unrelated donor. According to this short sample and previous reports, PBSC are a feasible option effectively used as the sole source of stem cells. Additionally, post-transplant cyclophosphamide remains a good strategy for GVHD prevention.


Assuntos
Anemia Aplástica/terapia , Antígenos CD34 , Transplante de Células-Tronco Hematopoéticas , Transplante Haploidêntico , Adolescente , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , México , Estudos Retrospectivos , Condicionamento Pré-Transplante
6.
Rev. Asoc. Argent. Ortop. Traumatol ; 86(5) (Nro Esp - AACM Asociación Argentina de Cirugía de la Mano): 601-612, 2021.
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1353966

RESUMO

Introducción: El síndrome del túnel carpiano es la neuropatía por atrapamiento más común que genera compresión del nervio mediano. La cirugía de liberación abierta del nervio mediano tiene un papel importante, especialmente, en pacientes que no responden al manejo conservador o con diagnóstico de síndrome del túnel carpiano con criterios de gravedad. El propósito de este estudio fue describir los resultados funcionales, la satisfacción y la fuerza objetiva a mediano (6-24 meses) y largo plazo (>24 meses) con la técnica abierta convencional en la población local. Materiales y métodos: Estudio observacional descriptivo con datos retrospectivos de resultados clínicos funcionales a mediano y largo plazo en pacientes sometidos a cirugía de liberación abierta del nervio mediano como tratamiento del síndrome del túnel carpiano. Se determinaron el nivel funcional según el BCTQ y la FSS, la fuerza de agarre con un dinamómetro electrónico y la satisfacción. Resultados: Se realizaron 100 procedimientos entre mayo de 2012 y septiembre de 2018, con un seguimiento posoperatorio >6 meses. La mayoría eran mujeres (83%) con una mediana de la edad de 59 años. El 97% obtuvo resultados buenos y excelentes a mediano plazo y el 90%, a largo plazo, con una mediana de fuerza de 17 kg (RIC 7,4) y una satisfacción de 90 (RIC 20) a mediano y largo plazo. Conclusiones: La cirugía abierta de liberación del nervio mediano en pacientes con síndrome del túnel carpiano logra resultados buenos y excelentes a mediano y largo plazo en cuanto a funcionalidad, fuerza y satisfacción. Nivel de Evidencia: IV


Introduction: Carpal tunnel syndrome (CTS) is the most common entrapment neuropathy that causes compression of the median nerve. Open median nerve release surgery plays an important role, especially in patients with failed conservative management or with a diagnosis of severe CTS. The purpose of the following study is to describe the functional outcomes, satisfaction, and objective strength in the medium (6 to 24 months) and long term (greater than 24 months) with the conventional open technique in the local population. Materials and methods: Descriptive observational study based on retrospective data of functional clinical outcomes in the medium and long term in patients undergoing open release surgery of the median nerve as a treatment for CTS. Functional level according to the BCTQ and FSS, grip strength with an electronic dynamometer, and satisfaction were determined. Results: 100 procedures were performed between May 2012 and September 2018, with a follow-up of more than 6 months. The majority were women (83%) with a total median age of 59 years showing good to excellent results in the 97% in the medium term and 90% in the long term, with a median strength of 17 kg (Interquartile range: 7.4) and satisfaction of 90 (Interquartile range: 20). Conclusions: Open surgery to release the median nerve in patients with CTS shows good to excellent functional outcomes, satisfaction, and strength in the medium and long term. Level of Evidence: IV


Assuntos
Adulto , Síndrome do Túnel Carpal/cirurgia , Resultado do Tratamento , Satisfação do Paciente , Eletromiografia , Força Muscular , Mãos
7.
Environ Sci Pollut Res Int ; 27(20): 25740-25753, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32356057

RESUMO

In tropical estuaries, fish diversity varies spatially and temporally due to behavioral processes such as reproductive migrations, predator avoidance, and foraging, which are affected by water quality. Eutrophication is one of the main factors affecting water quality in estuaries. The objective of this study was to determine variation in fish assemblage explained by fluctuating water quality in the Buenaventura Bay. Fish were captured using artisanal trawl nets during the wet, dry, and transitional seasons at four sampling sites. Additionally, alkalinity; phosphate, nitrite, and nitrate concentrations; dissolved oxygen; pH; temperature; and suspended solids were measured. Multivariate analysis was used to assess the effect of water quality on fish assemblage. In Buenaventura Bay, the assemblage composition of Pseudupeneus grandisquamis, Daector dowi, and Citharichthys gilberti was affected by nitrate concentration. Moreover, large fish biomasses were associated with high nitrite concentration, intermediate salinity, and low dissolved oxygen, suggesting that these estuaries are dominated by species tolerant to poor water quality. Species richness was associated with low nitrate and phosphate concentrations, more suitable water quality indicators, and intermediate temperatures. These results suggest that the deteriorating water quality of estuaries as a result of the anthropogenic impact could increase dominance and decrease richness, resulting in structural changes of fish assemblages.


Assuntos
Estuários , Qualidade da Água , Animais , Colômbia , Peixes , Salinidade , Estações do Ano
8.
Environ Sci Pollut Res Int ; 27(4): 4044-4057, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31823264

RESUMO

The environmental health of Buenaventura Bay, a highly impacted tropical estuary, is influenced by numerous human activities, including mining upstream. Large- and small-scale fishing plays an important role in the local economy, so we investigated the dynamic processes of bioaccumulation of mercury at basal trophic levels. Four samples were taken at each of the four locations in Buenaventura Bay during each of the four seasons of 2015. We measured the total mercury content (T-Hg, dry weight) in sediments and in muscle tissue across 17 macroinvertebrate species. The most abundant were the blue crab (C. arcuatus) and the mantis shrimp (S. aculeata aculeata). Blue crab showed an average muscle T-Hg value ​​exceeding the limit of 0.2 g·g-1, which is the maximum T-Hg level suggested for food consumption by vulnerable humans and populations: pregnant women, children, and the community that feeds from this source of protein on a daily basis. It was found that, 6.22% of individuals exceeded the 0.5 g·g-1 level, which is the maximum T-Hg level suggested for food consumption by the general population: the population that consumes it sporadically. Significantly high values ​​of T-Hg in blue crab and mantis shrimp occurred during low salinity conditions in the estuary, suggesting that Hg mainly originates from river runoff during the rainy season. Nevertheless, the biota-sediment accumulation factor (BSAF) was favored in high salinity, which could mean greater availability of Hg for higher levels of the estuarine food web in the dry season and in marine waters. In general, the T-Hg levels in some samples exceeded 0.2 g·g-1. Therefore this pollutant must be monitored due to its biomagnification potential and as a threat to human health, especially that for the local population of fishermen and their families.


Assuntos
Mercúrio , Animais , Baías , Braquiúros/química , Braquiúros/metabolismo , Criança , Colômbia , Monitoramento Ambiental , Estuários/estatística & dados numéricos , Feminino , Cadeia Alimentar , Humanos , Mercúrio/análise , Mercúrio/química , Gravidez , Rios
9.
Int J Hematol Oncol Stem Cell Res ; 13(3): 146-152, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31649805

RESUMO

Background: Lumbar puncture (LP) is a hematology procedure that can require repeated attempts leading to traumatic LP (TLP), which has been related to the central nervous system (CNS) relapse. LP success can depend on the size and anatomy of the patient and the skill of the hematologist. The main objective was to determine the influence of body mass index (BMI) on LP outcomes. Materials and Methods: Adults with lymphoid malignancies requiring LP were included prospectively over one year; hematology residents performed most procedures. A 22-gauge Quincke needle was employed. Comparison between non-traumatic vs. traumatic LPs according to BMI, CNS relapse, and residents' year was performed. Results: Fifty-four patients with a mean age of 31.5±15.57 years were included. Diagnosis was Acute Lymphoblastic Leukemia-B (74%), Acute Lymphoblastic Leukemia-T (13%) and Non-Hodgkin Lymphoma (13%). 227 LPs were performed, 121 (53.3%) successful, 98 (43.2%) traumatic, 11 (11.2%) TLPs were macroscopically detectable and 87 (88%) microscopic; 8 (3.5%) were dry-taps. Median time between punctures was 11 days (1-202). Median BMI was 25 (22.8-39.6). Main indication for LP was prophylactic (74.5%); 39.2% were performed by first-year, 35.2% by second-year, 19.6% by third-year hematology residents. No difference (p = 0.145) for a TLP was found among residents. A BMI ≥30 (p = 0.040), non-palpable intervertebral space (p = 0.001) and more than one attempt (p = 0.001) were significant for TLP. TLP was not associated with CNS relapse (p = 0.962). Conclusion: Obesity predicted a TLP. A traumatic puncture did not increase the risk of CNS relapse at one-year follow-up.

10.
Transfusion ; 59(12): 3721-3726, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31618456

RESUMO

BACKGROUND: Autologous stem cell transplantation (ASCT) is an effective treatment for patients with relapsing myeloma or lymphoma, diseases associated with unsuccessful peripheral blood stem cell (PBSC) collection. Plerixafor is a potent mobilizing agent, allowing more CD34+ cells to be obtained; however, the main obstacle for its use is its high cost. Our aim was to demonstrate that of the use of reduced doses of plerixafor (RD-plerixafor) can be sufficient to collect at least 2 × 106 /Kg CD34+ PBSC in patients with multiple myeloma (MM) or lymphoma undergoing ASCT. STUDY DESIGN AND METHODS: Twenty patients were mobilized with filgrastim (10 µg/kg/4 days) plus a single dose of plerixafor 0.12 mg/kg in Day 4. Apheresis collection was performed on Day 5. One vial of plerixafor was used for two patients. Clinicaltrials.gov NCT03244930. RESULTS: Cell mobilization and collection was successful in 85% of patients (≥2 × 106 CD34+ cells per kilogram). The median collected CD34+ cell count was 4.62 × 106 /kg (range, 1.27-24.5). A 4.1-fold-increase in the median CD34+ PBSC pre-count was observed (from 10.4/µl to 42.4/µl) after RD-plerixafor administration. Seven patients had mild to moderate adverse events. CONCLUSION: RD-plerixafor is an effective, safe, and affordable strategy to ensure adequate PBSC mobilization in patients with MM or lymphoma who undergo ASCT.


Assuntos
Transplante de Células-Tronco Hematopoéticas/métodos , Compostos Heterocíclicos/administração & dosagem , Compostos Heterocíclicos/uso terapêutico , Adulto , Idoso , Antígenos CD34/metabolismo , Benzilaminas , Remoção de Componentes Sanguíneos , Ciclamos , Feminino , Mobilização de Células-Tronco Hematopoéticas/métodos , Humanos , Linfoma/terapia , Masculino , Pessoa de Meia-Idade , Mieloma Múltiplo/terapia , Estudo de Prova de Conceito , Transplante Autólogo
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