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1.
Environ Sci Technol ; 58(41): 18122-18132, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-39365922

RESUMO

Aquatic organisms in the environment are frequently exposed to a variety of organic chemicals, while these biological species may show different sensitivities to different chemical groups present in the environment. This study evaluated species sensitivity, hazards, and risks of six classes of organic chemicals in the aquatic environment. None of the taxonomic groups were the most sensitive or tolerant to all chemicals, as one group sensitive to one class of chemicals might possess adaptations to other chemical groups. Polychlorinated biphenyls were generally the most toxic chemical group, followed by polybrominated diphenyl ethers, polycyclic aromatic hydrocarbons, and pharmaceuticals and personal care products, while per- and polyfluoroalkyl substances and phthalate esters were the less toxic chemical groups. The hazard of organic chemicals was closely related to their physicochemical properties, including hydrophobicity and molecular weight. It was shown that 20% of the evaluated chemicals exhibited medium or high ecological risks with the worst-case scenario in the Pearl River Estuary. This novel work represented a comprehensive comparison of chemical hazards and species sensitivity among different classes of organic chemicals, and the reported results herein have provided scientific evidence for ecological risk assessment and water quality management to protect aquatic ecosystems against organic chemicals.


Assuntos
Éteres Difenil Halogenados , Bifenilos Policlorados , Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Medição de Risco , Poluentes Químicos da Água/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/toxicidade , Hidrocarbonetos Policíclicos Aromáticos/análise , Éteres Difenil Halogenados/toxicidade , Bifenilos Policlorados/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Compostos Orgânicos/toxicidade , Animais , Monitoramento Ambiental , Ecossistema
2.
Environ Res ; 251(Pt 1): 118614, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38462084

RESUMO

Organophosphate esters (OPEs) have been widely used as flame retardants and plasticizers in consumer and industrial products. They have been found to have numerous exposure hazards. Recently, several OPEs have been detected in surface waters around the world, which may pose potential ecological risks to freshwater organisms. In this study, the concentration, spatial variation, and ecological risk of 15 OPEs in the Beiyun and Yongding rivers were unprecedentedly investigated by the ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) and risk quotient (RQ) method. The result showed that triethyl phosphate (TEP), tri (2-chloroisopropyl) phosphate (TCPP) were the most abundant OPEs with average concentrations of 55.53 ng/L and 42.29 ng/L, respectively. The concentrations of OPEs in the Beiyun River are higher than in the Yongding River, and their levels were higher in densely populated and industrial areas. The risk assessment showed that there was insignificant from OPEs to freshwater organisms in these rivers (RQs <0.1). The risk was higher downstream than upstream, which was related to human-intensive industrial activities downstream in the Yongding River. The ecological risk of OPEs in surface waters worldwide was estimated by joint probability curves (JPCs), and the result showed that there was a moderate risk for tri (2-chloroethyl) phosphate (TCEP), a low risk for trimethyl phosphate (TMP), and insignificant for other OPEs. In addition, the QSAR-ICE-SSD model was used to calculate the hazardous concentration for 5% (HC5). This result validated the feasibility and accuracy of this model in predicting acute data of OPEs and reducing biological experiments on the toxicity of OPEs. These results revealed the ecological risk of OPEs and provided the scientific basis for environmental managers.


Assuntos
Monitoramento Ambiental , Organofosfatos , Rios , Poluentes Químicos da Água , Medição de Risco , Poluentes Químicos da Água/análise , Organofosfatos/análise , Rios/química , Ésteres/análise , China , Espectrometria de Massas em Tandem , Retardadores de Chama/análise , Cidades
3.
Environ Res ; 255: 119174, 2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-38763284

RESUMO

In near-natural basins, zooplankton are key hubs for maintaining aquatic food webs and organic matter cycles. However, the spatial patterns and drivers of zooplankton in streams are poorly understood. This study registered 165 species of zooplankton from 147 sampling sites (Protozoa, Rotifers, Cladocera and Copepods), integrating multiple dimensions (i.e., taxonomic, functional, and phylogenetic) and components (i.e., total, turnover, and nestedness) of α and ß diversity. This study aims to reveal spatial patterns, mechanisms, correlations, and relative contribution of abiotic factors (i.e., local environment, geo-climatic, land use, and spatial factors) through spatial interpolation (ordinary kriging), mantel test, and variance partitioning analysis (VPA). The study found that α diversity is concentrated in the north, while ß diversity is more in the west, which may be affected by typical habitat, hydrological dynamics and underlying mechanisms. Taxonomic and phylogenetic ß diversity is dominated by turnover, and metacommunity heterogeneity is the result of substitution of species and phylogeny along environmental spatial gradients. Taxonomic and phylogenetic ß diversity were strongly correlated (r from 0.91 to 0.95), mainly explained by historical/spatial isolation processes, community composition, generation time, and reproductive characteristics, and this correlation provides surrogate information for freshwater conservation priorities. In addition, spatial factors affect functional and phylogenetic α diversity (26%, 28%), and environmental filtering and spatial processes combine to drive taxonomic α diversity (10%) and phylogenetic ß diversity (11%). Studies suggest that spatial factors are key to controlling the community structure of zooplankton assemblages in near-natural streams, and that the relative role of local environments may depend on the dispersal capacity of species. In terms of diversity conservation, sites with high variation in uniqueness should be protected (i) with a focus on the western part of the thousand islands lake catchment and (ii) increasing effective dispersal between communities to facilitate genetic and food chain transmission.


Assuntos
Biodiversidade , Rios , Zooplâncton , Animais , Zooplâncton/classificação , Filogenia , Ecossistema
4.
Surg Endosc ; 38(5): 2788-2794, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38587640

RESUMO

AIM: To analyze efficacy of endoscopic lithotripsy combined with drug lithotripsy as compared with drug lithotripsy for the treatment of phytobezoars. METHODS: We collected and evaluated case records of 165 patients with phytobezoars from 2014 to 2023. And we analyzed demographic and clinical characteristics, imaging features, endoscopic features, complications of phytobezoars, and compared efficacy between endoscopic lithotripsy combined with drug lithotripsy (Group A) and drug lithotripsy (sodium bicarbonate combined with proton pump inhibitor) (Group B). RESULTS: The median age of patients with phytobezoars was 67.84 ± 4.286 years old. Abdominal pain was the most common symptom and peptic ulcers (67.5%) were the most common complication. Bezoar-induced ulcers were more frequent in the gastric angle. The success rate of phytobezoars vanishing in Group A and Group B were similar (92.3% vs. 85.1% within 48 h, 98.7% vs. 97.7% within a week), while the average hospitalization period, average hospitalization cost, second endoscopy rate, and average endoscopic operation time were significantly lower in patients in Group B than in Group A. CONCLUSION: Drug lithotripsy is the preferred effective and safe treatment option for phytobezoars. We advise that an endoscopy should be completed after 48 h for drug lithotripsy.


Assuntos
Bezoares , Litotripsia , Humanos , Bezoares/terapia , Masculino , Feminino , Litotripsia/métodos , Idoso , Pessoa de Meia-Idade , Estudos Retrospectivos , Inibidores da Bomba de Prótons/uso terapêutico , Inibidores da Bomba de Prótons/administração & dosagem , Resultado do Tratamento , Bicarbonato de Sódio/administração & dosagem , Bicarbonato de Sódio/uso terapêutico , Terapia Combinada , Dor Abdominal/etiologia , Dor Abdominal/terapia
5.
Proc Natl Acad Sci U S A ; 118(7)2021 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-33531347

RESUMO

Cell-cell adhesions are often subjected to mechanical strains of different rates and magnitudes in normal tissue function. However, the rate-dependent mechanical behavior of individual cell-cell adhesions has not been fully characterized due to the lack of proper experimental techniques and therefore remains elusive. This is particularly true under large strain conditions, which may potentially lead to cell-cell adhesion dissociation and ultimately tissue fracture. In this study, we designed and fabricated a single-cell adhesion micro tensile tester (SCAµTT) using two-photon polymerization and performed displacement-controlled tensile tests of individual pairs of adherent epithelial cells with a mature cell-cell adhesion. Straining the cytoskeleton-cell adhesion complex system reveals a passive shear-thinning viscoelastic behavior and a rate-dependent active stress-relaxation mechanism mediated by cytoskeleton growth. Under low strain rates, stress relaxation mediated by the cytoskeleton can effectively relax junctional stress buildup and prevent adhesion bond rupture. Cadherin bond dissociation also exhibits rate-dependent strengthening, in which increased strain rate results in elevated stress levels at which cadherin bonds fail. This bond dissociation becomes a synchronized catastrophic event that leads to junction fracture at high strain rates. Even at high strain rates, a single cell-cell junction displays a remarkable tensile strength to sustain a strain as much as 200% before complete junction rupture. Collectively, the platform and the biophysical understandings in this study are expected to build a foundation for the mechanistic investigation of the adaptive viscoelasticity of the cell-cell junction.


Assuntos
Junções Intercelulares/metabolismo , Estresse Mecânico , Caderinas/metabolismo , Adesão Celular , Linhagem Celular Tumoral , Citoesqueleto/metabolismo , Elasticidade , Humanos , Junções Intercelulares/química , Viscosidade
6.
Ecotoxicol Environ Saf ; 279: 116517, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38805830

RESUMO

With increasing urbanization and rapid industrialization, more and more environmental problems have arisen. Phthalates (PAEs) are the foremost and most widespread plasticizers and are readily emitted from these manufactured products into the environment. PAEs act as endocrine-disrupting chemicals (EDCs) and can have serious impacts on aquatic organisms as well as human health. In this study, the water quality criteria (WQC) of five PAEs (dimethyl phthalate (DMP), diethyl phthalate (DEP), dibutyl phthalate (DBP), butyl benzyl phthalate (BBP) and di(2-ethylhexyl) phthalate (DEHP)) for freshwater aquatic organisms were developed using a species sensitivity distribution (SSD) and a toxicity percentage ranking (TPR) approach. The results showed that long-term water quality criteria (LWQC) of PAEs using the SSD method could be 13.7, 11.1, 2.8, 7.8, and 0.53 µg/L, respectively. Criteria continuous concentrations (CCC) of PAEs were derived using the TPR method and determined to be 28.4, 13.1, 1.3, 2.5, and 1.6 µg/L, respectively. The five PAEs are commonly measured in China surface waters at concentrations between ng/L and µg/L. DBP, DEHP, and di-n-octyl phthalate (DnOP) were the most frequently detected PAEs, with occurrence rates ranging from 67% to 100%. The ecological risk assessment results of PAEs showed a decreasing order of risk at the national level, DEHP, DBP, DMP, DEP, DnOP. The results of this study will be of great benefit to China and other countries in revising water quality standards for the conservation of aquatic species.


Assuntos
Monitoramento Ambiental , Água Doce , Ácidos Ftálicos , Plastificantes , Poluentes Químicos da Água , Qualidade da Água , Ácidos Ftálicos/análise , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade , Qualidade da Água/normas , Água Doce/química , Monitoramento Ambiental/métodos , Plastificantes/análise , Plastificantes/toxicidade , Disruptores Endócrinos/análise , Disruptores Endócrinos/toxicidade , Organismos Aquáticos/efeitos dos fármacos , Ésteres , China , Animais , Dibutilftalato/toxicidade
7.
BMC Surg ; 24(1): 162, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762739

RESUMO

OBJECTIVES: To compare the efficacy of nadroparin and fondaparinux sodium for prevention of deep vein thromboembolism (DVT) in lower extremities after total hip arthroplasty (THA) and total knee arthroplasty (TKA). METHODS: A total of 592 patients were enrolled in the study. Clinical data of patients who underwent total hip arthroplasty (THA) and total knee arthroplasty (TKA) in our hospital from December 2021 to September 2022 were retrospectively collected, which mainly included patients' general information, surgery-related information, and DVT-related information. The patients were categorized into the nadroparin group(n = 278) and the fondaparinux sodium group(n = 314) according to the types of anticoagulants used. Anticoagulant therapy began 12-24 h after operation and continued until discharge. DVT prevalence between two groups was compared. The Statistical Package for Social Sciences (SPSS) software version 25 (SPSS, Armonk, NY, USA) was used for statistical analysis. RESULTS: The prevalence of DVT in the nadroparin group and the fondaparinux sodium group was 8.3% (23/278) and 15.0% (47/314), respectively(p = 0.012). Statistical analysis showed that nadroparin group showed a lower prevalence of thrombosis than fondaparinux group (OR = 1.952, P = 0.012). Subgroup analyses showed that nadroparin group had a lower prevalence of DVT than fondaparinux group in some special patients groups such as female patients (OR = 2.258, P = 0.007), patients who are 65-79 years old (OR = 2.796, P = 0.004), patients with hypertension (OR = 2.237, P = 0.042), patients who underwent TKA (OR = 2.091, P = 0.011), and patients who underwent combined spinal-epidural anesthesia (OR = 2.490, P = 0.003) (P < 0.05). CONCLUSION: Nadroparin may have an advantage over fondaparinux sodium in preventing DVT in lower extremities after THA and TKA.


Assuntos
Anticoagulantes , Artroplastia de Quadril , Artroplastia do Joelho , Fondaparinux , Nadroparina , Complicações Pós-Operatórias , Tromboembolia Venosa , Humanos , Fondaparinux/uso terapêutico , Feminino , Masculino , Estudos Retrospectivos , Artroplastia de Quadril/efeitos adversos , Artroplastia do Joelho/efeitos adversos , Nadroparina/uso terapêutico , Nadroparina/administração & dosagem , Pessoa de Meia-Idade , Tromboembolia Venosa/prevenção & controle , Tromboembolia Venosa/etiologia , Tromboembolia Venosa/epidemiologia , Idoso , Anticoagulantes/uso terapêutico , Anticoagulantes/administração & dosagem , Complicações Pós-Operatórias/prevenção & controle , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/etiologia , Extremidade Inferior/irrigação sanguínea , Extremidade Inferior/cirurgia , Resultado do Tratamento
8.
Langmuir ; 39(40): 14308-14327, 2023 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-37751568

RESUMO

We have studied the effect of platinum underlayer for two deposited thicknesses on the microstructure, crystalline quality, morphology, chemical composition, and magnetic properties as well as magnetic domain formation of BaFe12O19 (BaM) grown on YSZ(111) by pulsed laser deposition (PLD). We found that PLD platinum deposited with a thickness of 25 nm cannot withstand the dewetting phenomenon occurring during the subsequent BaM layer growth. A smooth and continuous Pt underlayer that possesses a sharp interface and omits the intermixing between the BaM and substrate was successfully achieved for a deposited Pt film thickness of 75 nm. Independent of the thickness of the deposited Pt layer, the c-axis orientation as well as coercivity Hc and the anisotropy HA fields were significantly improved due to a remarkable improvement of lattice mismatch in comparison with the BaM layer grown without a Pt underlayer on YSZ(111). By applying high-resolution X-ray diffraction, scanning and transmission electron microscopy (SEM/TEM), and atomically resolved scanning TEM imaging combined with energy-dispersive X-ray spectroscopy, as well as atomic and magnetic force microscopy, a comprehensive investigation of both structure and chemical composition of the deposited BaM films and their interfacial regions was performed. This study aimed to correlate the enhancement of the overall magnetic properties and of the local spin magnetic domain orientation with the modification of BaM microstructure and chemical composition at the nanometer scale due to the Pt underlayer. Finally, we attempted to understand the mechanisms that control the magnetic properties of these BaM films in order to be able to tailor them.

9.
Mol Cell Biochem ; 2023 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-37747676

RESUMO

The onset of non-small cell lung carcinoma (NSCLC) still be in the fog. LUCAT1 is potentially capable of modulating MCL-1-involved NSCLC pathogenesis via targeting SRSF1. Also, MCL-1 can regulate Wnt/ß-catenin pathway to affect the tumorigenesis of NSCLC. Thus, this paper aims to uncover an intriguing and novel role of LUCAT1/SRSF1/MCL-1 axis in NSCLC based on Wnt/ß-catenin pathway. A549 and NCI-H1650, two cell lines of NSCLC, were used to mimic NSCLC in vitro. MCL-1 siRNA (si-MCL-1) and LUCAT1 siRNA (si-LUCAT1) were used to downregulate MCL-1 and LUCAT1 in NSCLC cells, respectively. The overexpression vector of SRSF1 based on pcDNA 3.1 was constructed to upregulate SRSF1 expression. 40 µM SKL2001 was used to activate Wnt/ß-catenin pathway. Transwell assay was used for migrative and invasive tests. The effect of LUCAT1 on tumor metastasis was verified in nude mice. MCL-1 downregulation led to the decrease of EMT, invasion, and migration in NSCLC, while Wnt/ß-catenin pathway agonist partially reversed the effects of MCL-1 downregulation. Mechanistic investigations revealed that LUCAT1 and MCL-1 mRNA were enriched in SRSF1; LUCAT1 silence decreased MCL-1, whereas SRSF1 enhancement elevated MCL-1; Importantly, SRSF1 overexpression significantly reversed MCL-1 alteration due to LUCAT1 silence. In NSCLC cells, SRSF1 overexpression offset the si-LUCAT1-induced changes, and si-MCL-1 reversed the SRSF1-induced cellular changes. Further, LUCAT1 inhibition reduced lung metastasis of cancer cells. LUCAT1 can interact with SRSF1 to regulate MCL-1 expression that targets the Wnt/ß-catenin pathway-mediated NSCLC cell migration, invasion, and EMT.

10.
Scand J Gastroenterol ; 58(7): 805-812, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36651020

RESUMO

BACKGROUND: To analyze the diversity in endoscopic manifestations of Meckel's diverticulum (MD) in adults by using balloon-assisted enteroscopy (BAE) and supply more information on the application of BAE. METHODS: A retrospective study was carried out on adult patients diagnosed with MD by BAE in two tertiary general hospitals in China, from May 2007 to September 2021. The patients were divided into a small bowel bleeding (SBB) group and a control group according to their main symptoms. Clinical charts and endoscopic images were reviewed, analyzed, and summarized. RESULTS: Single diverticulum in the ileum and double-lumen sign were observed in all patients. The SBB group consisted of 51 patients, among which 35 cases of ulcerative lesions, 9 cases of erosive lesions, 9 cases of active bleeding/blood clots, and 4 cases of lumps inside the diverticulum were observed respectively. Majority of ulcerative lesions were inside the diverticulum (23/35). A circumferential stricture inside the diverticulum was discovered in 11 cases, and ulcerative lesions tended to occur at this structure (10/11). In the control group consisting of 15 patients, 1 case of erosive lesions at the orifice edge was observed. The percentage of patients with MD-associated ulcerative lesions was significantly higher in the SBB group than that in the control group (p < 0.001). CONCLUSIONS: The endoscopic manifestations of MD in adults are extraordinarily complex and connected with the patients' primary symptoms. The internal features of MD should be regarded as crucial observational objectives in adult patients.


Assuntos
Divertículo Ileal , Humanos , Adulto , Divertículo Ileal/complicações , Divertículo Ileal/diagnóstico , Estudos Retrospectivos , Hospitais Gerais , Íleo/patologia , China , Hemorragia Gastrointestinal/diagnóstico
11.
Conserv Biol ; 37(3): e14036, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-36424856

RESUMO

The lack of high-resolution distribution maps for freshwater species across large extents fundamentally challenges biodiversity conservation worldwide. We devised a simple framework to delineate the distributions of freshwater fishes in a high-resolution drainage map based on stacked species distribution models and expert information. We applied this framework to the entire Chinese freshwater fish fauna (>1600 species) to examine high-resolution biodiversity patterns and reveal potential conflicts between freshwater biodiversity and anthropogenic disturbances. The correlations between spatial patterns of biodiversity facets (species richness, endemicity, and phylogenetic diversity) were all significant (r = 0.43-0.98, p < 0.001). Areas with high values of different biodiversity facets overlapped with anthropogenic disturbances. Existing protected areas (PAs), covering 22% of China's territory, protected 25-29% of fish habitats, 16-23% of species, and 30-31% of priority conservation areas. Moreover, 6-21% of the species were completely unprotected. These results suggest the need for extending the network of PAs to ensure the conservation of China's freshwater fishes and the goods and services they provide. Specifically, middle to low reaches of large rivers and their associated lakes from northeast to southwest China hosted the most diverse species assemblages and thus should be the target of future expansions of the network of PAs. More generally, our framework, which can be used to draw high-resolution freshwater biodiversity maps combining species occurrence data and expert knowledge on species distribution, provides an efficient way to design PAs regardless of the ecosystem, taxonomic group, or region considered.


Potenciación de la conservación de peces de agua dulce con mapeos de distribución de alta resolución a lo largo de un territorio extenso Resumen La falta de mapas de distribución en alta resolución para las especies de agua dulce en grandes extensiones es un reto importante para la conservación mundial de la biodiversidad. Diseñamos un marco simple para delinear la distribución de los peces de agua dulce en un mapa de drenaje en alta resolución basado en los modelos apilados de la distribución de las especies y la información de expertos. Aplicamos este marco a toda la ictiofauna de agua dulce en China (>1600 especies) para analizar los patrones en alta resolución de la biodiversidad y revelar los conflictos potenciales entre la biodiversidad de agua dulce y las perturbaciones antropogénicas. Todas las correlaciones entre los patrones espaciales de las facetas de la biodiversidad (riqueza de especies, endemismo y diversidad filogenética) fueron importantes (r = 0.43-0.98, p < 0.001). Las áreas con valores altos de diferentes facetas de la biodiversidad se traslaparon con las perturbaciones antropogénicas. Las áreas protegidas existentes que actualmente cubren el 22% del territorio de China, protegen 25-2% del hábitat de los peces, 16-23% de las especies y 30-31% de las áreas de conservación prioritarias. Además, 6-21% de las especies se encontraban totalmente desprotegidas. Estos resultados sugieren que se necesita extender la red de áreas protegidas para asegurar la conservación de los peces de agua dulce de China y los bienes y servicios que proporcionan. En concreto, los niveles medio a bajo de los grandes ríos y sus lagos asociados del noreste al suroeste de China albergaron los ensambles de especies más diversos y por lo tanto deberían ser el objetivo de las futuras expansiones de la red de áreas protegidas. De forma más generalizada, nuestro marco, el cual puede usarse para trazar mapas en alta resolución de la biodiversidad de agua dulce al combinar los datos de presencia de las especies y el conocimiento de los expertos sobre su distribución, proporciona un método eficiente para diseñar las áreas protegidas sin importar el ecosistema, región o grupo taxonómico considerado.


Assuntos
Conservação dos Recursos Naturais , Ecossistema , Animais , Filogenia , Conservação dos Recursos Naturais/métodos , Peixes , Lagos
12.
J Environ Manage ; 339: 117822, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37054589

RESUMO

Triadimefon is ubiquitous in various environmental media. Although toxicity of triadimefon to individual of aquatic organisms has been confirmed, its effect on organisms at population level remain poorly understood. In this study the long-term effect of triadimefon on individual and population of Daphnia magna were studied using multi-generational experiments and matrix model. Development and reproduction of three generations of F1 and F2 were significantly inhibited with the triadimefon concentration of 0.1 mg/L (p < 0.01). Toxicity of triadimefon to the offspring was stronger than to the parent (p < 0.05). When triadimefon concentration was higher than 0.1 mg/L, both population number and intrinsic rate of increase showed a decreasing trend with the increasing exposure concentration. Age structure of the population also tended to decline. Toxicity threshold derived on population-level was between mortality-based LC50 and reproduction-based NOEC of Daphnia magna, and also between acute toxicity and chronic toxicity derived from species sensitivity distribution (SSD). The risk of population level derived from risk quotient was low for most areas, and the results derived from probability risk showed that the expected loss of intrinsic rate of increase of population was 0.0039 without considering other factors. Compared to the individual-level, the ecological risks at the population level were closer to the actual situation of the ecosystem response to the chemical pollution.


Assuntos
Fungicidas Industriais , Poluentes Químicos da Água , Animais , Daphnia/fisiologia , Fungicidas Industriais/toxicidade , Fungicidas Industriais/química , Ecossistema , Poluentes Químicos da Água/toxicidade , Reprodução
13.
J Environ Manage ; 341: 118017, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37150169

RESUMO

Biodiversity loss is caused by intensive human activities and threatens human well-being. However, less is known about how the combined effects of multiple stressors on the diversity of internal (alpha diversity) and multidimensional (beta diversity) communities. Here, we conducted a long-term experiment to quantify the contribution of environmental stressors (including water quality, land use, climate factors, and hydrological regimes) to macroinvertebrate communities alpha and beta diversity in the mainstream of the Songhua River, the third largest river in China, from 2012 to 2019. Our results demonstrated that the alpha and beta diversity indices showed a decline during the study period, with the dissimilarity in community composition between sites decreasing significantly, especially in the impacted river sections (upper and midstream). Despite overall improvement in water quality after management intervention, multiple human-caused stressors still have led to biotic homogenization of macroinvertebrate communities in terms of both taxonomic and functional diversities in the past decade. Our study revealed the increased human land use explained an important portion of the variation of diversities, further indirectly promoting biotic homogenization by changing the physical and chemical factors of water quality, ultimately altering assemblage ecological processes. Furthermore, the facets of diversity have distinct response mechanisms to stressors, providing complementary information from the perspective of taxonomy and function to better reflect the ecological changes of communities. Environmental filtering determined taxonomic beta diversity, and functional beta diversity was driven by the joint efforts of stressors and spatial processes. Finally, we proposed that traditional water quality monitoring alone cannot fully reveal the status of river ecological environment protection, and more importantly, we should explore the continuous changes in biodiversity over the long term. Meanwhile, our results also highlight timely control of nutrient input and unreasonable expansion of land use can better curb the ecological degradation of rivers and promote the healthy and sustainable development of floodplain ecosystems.


Assuntos
Ecossistema , Invertebrados , Animais , Humanos , Invertebrados/fisiologia , Efeitos Antropogênicos , Monitoramento Ambiental/métodos , Biodiversidade , China
14.
J Environ Manage ; 342: 118344, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37320921

RESUMO

Freshwater biodiversity and ecosystem services might decline due to exposure to chemicals. However, researchers have devoted much attention to the potential risks of emerging contaminants, while placing less effort on historical pollutants, such as the surfactant, linear-alkylbenzene-sulfonate (LAS), which is a major component of widely used synthetic detergents worldwide. In this study, a multilevel risk assessment approach was used to assess risks posed by LAS to aquatic organisms, on a wide spatial scale, based on various assessment endpoints. Additionally, bottom-up approaches were used to assess contributions of LAS source discharges to aquatic environments. Concentrations of LAS in surface waters of China ranged from less than the limit of detection to 14,200 µg/L. The predicted no effect concentration (PNEC) based on adverse effects on reproduction is 15 µg/L, which is slightly less than the PNEC based on other endpoints. 99% of surface waters in Chaohu Lake and the Hai River (Ch: Haihe) were predicted to pose a risk to growth of aquatic organisms, with a protection threshold of 5% of species (HC5). Discharges of LAS were estimated using activity data and emission factors for 280 major cities in the basin. Rural domestic sources were the main source of LAS to surface waters. These outcomes provided a process for developing comprehensive management and control approaches to help researchers and policymakers effectively manage water resources affected by increasing concentrations of LAS.


Assuntos
Ácidos Alcanossulfônicos , Poluentes Ambientais , Ecossistema , Lagos
15.
AAPS PharmSciTech ; 24(7): 197, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37783919

RESUMO

The objective of this study was to create a new method for delivering oral borneol (BN) drug that would improve stability. This was accomplished through microencapsulation using HiCap®100 and maltodextrin (MD), resulting in HiCap®100/MD/BN microcapsules (MCs). The HiCap®100/MD/BN MCs were evaluated in terms of encapsulation efficiency (EE%), drug loading (DL%), morphological observations, particle size distribution, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), thermal analysis, drug degradation rate studies, and in vitro release behavior. The effect of MCs on intestinal permeability in a rat model was assessed using the model drug "florfenicol" (FF) in single-pass intestinal perfusion (SPIP) study. The relationship between MCs and P-glycoprotein (P-gp) was further investigated in comparison with verapamil (Ver). The irritation of MCs was assessed by histological analysis. The MCs in a spherical structure with micron-scale dimensions were obtained. The EE% and DL% were (86.71 ± 0.96)% and (6.03 ± 0.32)%, respectively. MCs played a significantly protective role in drug degradation rate studies. In vitro release studies indicated that the release behavior of MCs was significantly better than BN at the three-release media, and the cumulative release rate exceeded 90% in 15 min. The SPIP studies showed that MCs significantly enhanced the absorption of FF in rats. Compared with Ver, MCs were not promoted by a single inhibition of P-gp. Hematoxylin-eosin (HE)-stained images showed that MCs had no obvious irritation and toxic effects on the intestines of rats. Thus, the preparation of HiCap®100/MD/BN MCs improves the stability of BN, which has certain scientific value for the development and application of BN, and provides unique perspectives for future BN-related researches.


Assuntos
Absorção Intestinal , Intestinos , Ratos , Animais , Espectroscopia de Infravermelho com Transformada de Fourier , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Membro 1 da Subfamília B de Cassetes de Ligação de ATP/metabolismo
16.
J Environ Sci (China) ; 127: 495-507, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522080

RESUMO

Copper (Cu) exists in a variety of forms in different aquatic environments, and affects their bioavailability. In this study we provide a systematic review on toxicity of Cu which focuses on identifying evidence in the mechanisms of Cu toxicity, and apply an adverse outcome pathway (AOP) analysis to identify multiple potential mechanisms and their interactions of Cu toxicity to fish. This analysis process included the mechanisms of behavior toxicant, oxidative toxicant, ion regulation disruption toxicity, as well as endocrine disruption toxicity. It was found that at low levels of Cu exposure, swimming, avoid predators, locating prey and other sensory functions will be impaired, and the organism will suffer from metabolic alkalosis and respiratory acidosis following the inhibition of the carbonic anhydrase active. The main pathway of acute toxicity of Cu to fish is the inhibition of the Na+/K+-ATPase enzyme, and lead to reduced intracellular sodium absorption, as well as Cu-induced increased cell permeability, in turn resulting in increased sodium ion loss, leading to cardiovascular collapse and respiratory insufficiency. The endocrine disruption toxicity of Cu to fish caused growth inhibition and reproductive reduction. In addition, there are several key pathways of Cu toxicity that are affected by hardness (e.g., Ca2+) and intracellular DOC concentrations, including inhibiting Cu-induction, improving branchial gas exchange, altering membrane transport functions, decreasing Na+ loss, and increasing Na+ uptake. The results of the AOP analysis will provide a robust framework for future directed research on the mechanisms of Cu toxicity.


Assuntos
Rotas de Resultados Adversos , Poluentes Químicos da Água , Animais , Cobre/toxicidade , Cobre/análise , Disponibilidade Biológica , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Sódio , Peixes/metabolismo , Íons
17.
Biomed Microdevices ; 24(4): 33, 2022 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-36207557

RESUMO

We previously reported a single-cell adhesion micro tensile tester (SCAµTT) fabricated from IP-S photoresin with two-photon polymerization (TPP) for investigating the mechanics of a single cell-cell junction under defined tensile loading. A major limitation of the platform is the autofluorescence of IP-S, the photoresin for TPP fabrication, which significantly increases background signal and makes fluorescent imaging of stretched cells difficult. In this study, we report the design and fabrication of a new SCAµTT platform that mitigates autofluorescence and demonstrate its capability in imaging a single cell pair as its mutual junction is stretched. By employing a two-material design using IP-S and IP-Visio, a photoresin with reduced autofluorescence, we show a significant reduction in autofluorescence of the platform. Further, by integrating apertures onto the substrate with a gold coating, the influence of autofluorescence on imaging is almost completely mitigated. With this new platform, we demonstrate the ability to image a pair of epithelial cells as they are stretched up to 250% strain, allowing us to observe junction rupture and F-actin retraction while simultaneously recording the accumulation of over 800 kPa of stress in the junction. The platform and methodology presented here can potentially enable detailed investigation of the mechanics of and mechanotransduction in cell-cell junctions and improve the design of other TPP platforms in mechanobiology applications.


Assuntos
Actinas , Mecanotransdução Celular , Actinas/metabolismo , Ouro , Junções Intercelulares/metabolismo , Polimerização
18.
Anticancer Drugs ; 33(1): e349-e361, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34407051

RESUMO

Circular RNAs (circRNAs) play critical roles in regulating the radiosensitivity of various cancers, including esophageal squamous cell carcinoma (ESCC). This research aimed to explore the role and potential mechanism of hsa_circ_0014879 in regulating ESCC radioresistance. The levels of hsa_circ_0014879, microRNA-519-3p (miR-519-3p) and cell division cycle 25A (CDC25A) were measured using quantitative real-time PCR or western blot. Cell proliferation was evaluated by colony formation assay. Cell migration and invasion were assessed by transwell and scratch assays. The levels of epithelial-mesenchymal transition (EMT)-related proteins were detected by western blot. Xenograft assay was used to analyze the effect of hsa_circ_0014879 on radiosensitivity in vivo. The binding relationship among hsa_circ_0014879, miR-519-3p and CDC25A was confirmed by dual-luciferase reporter assay. Hsa_circ_0014879 and CDC25A were upregulated, whereas miR-519-3p was downregulated in radio-resistant ESCC tissues and cells. Depletion of hsa_circ_0014879 suppressed the proliferation, migration and invasion of radio-resistant ESCC cells. Hsa_circ_0014879 knockdown elevated radiosensitivity of radio-resistant cells by modulating miR-519-3p. Moreover, miR-519-3p enhanced the radiosensitivity of radio-resistant cells by targeting CDC25A. Also, hsa_circ_0014879 upregulated CDC25A via sponging miR-519-3p. Hsa_circ_0014879 silencing enhanced the radiosensitivity of ESCC via regulating the miR-519-3p/CDC25A pathway.


Assuntos
Neoplasias Esofágicas/patologia , Carcinoma de Células Escamosas do Esôfago/patologia , MicroRNAs/metabolismo , RNA Circular/genética , Tolerância a Radiação/genética , Fosfatases cdc25/metabolismo , Animais , Movimento Celular/fisiologia , Proliferação de Células/fisiologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Ensaios Antitumorais Modelo de Xenoenxerto
19.
Langmuir ; 37(2): 734-749, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33406840

RESUMO

Optimizing and monitoring the growth conditions of Pt films, often used as bottom electrodes in multiferroic material systems, represents a highly relevant issue that is of importance for controlling the crystalline quality and performance of ferroelectric oxides such as, e.g. LuFeO3. We performed a time-resolved monitoring of the growth and morphology of Pt films during pulsed laser deposition (PLD) in dependence on the grown film effective thickness and on the growth temperature Tg using in situ grazing incidence small-angle X-ray scattering (GISAXS). Through real-time analysis and modeling of GISAXS patterns, we could fully characterize the influence of Tg on the morphology and on the growth kinetics of the Pt layers. Consequently, critical and characteristic effective thicknesses for the transitions nucleation phase (I)/coalescence phase (II) and coalescence phase (II)/coarsening phase (III) could be determined. In combination with complementary microscopic imaging and chemical mapping via combined SEM/EDXS, we demonstrate the occurrence of a morphological progression in the Pt PLD-grown Pt films, changing from grains at room temperature to a 3D-island morphology at 300 °C, further to a hole-free structure at 500 °C, and finally to a channel structure for 700 and 900 °C. The film topography, as characterized by atomic force microscopy (AFM), favors the PLD growth of Pt layers at temperatures beyond 700 °C where the film is homogeneous, continuous, and hole-free with a flat and smooth surface. The double dependency of the percolation transition on the film effective thickness and on the growth temperature has been established by measuring the electrical conductivity.

20.
Dig Dis Sci ; 65(9): 2630-2636, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31894488

RESUMO

BACKGROUND: Predictors besides symptoms of obstruction indicating small bowel stenosis are little known. AIMS: To detect predictors of small bowel stenosis in balloon-assisted enteroscopy. METHODS: Over a 6-year period, 461 patients had enteroscopy for suspected small intestinal disease. Details of clinical manifestations, medical history, demographic characteristics, findings of examinations, information on enteroscopy, and treatment were retrospectively collected based on medical records. Small bowel stenosis was defined as stricture that over-tube cannot go through in enteroscopy. Univariate and multivariate analyses were performed to identify predictors for small bowel stenosis. RESULTS: A total of 314 patients had definite diagnosis after enteroscopy, imaging modalities, and/or even surgical exploration. They were included in this study for analyses. Mean age for them was 48.2 years old (range 15-81 years). Small bowel stenosis was present in 59 patients (18.8%). Analyses showed that CT/MRI indicating stenosis was significantly associated with severe stenosis (p = 0.014) but insignificant related to general stenosis (p = 0.097). Predictive factors that accompanied stenosis were age ≥ 60 years (OR = 2.1, 95% CI 1.1-4.0), underweight (BMI ≤ 18.5) (OR = 3.4, 95% CI 1.4-8.4), symptoms of obstruction (OR = 3.6, 95% CI 1.8-7.4), and overt small bowel bleeding (OR = 0.5, 95% CI 0.2-0.9). CONCLUSIONS: Small bowel stenosis more tended to occur to patients with symptoms of obstruction, no overt small bowel bleeding, age ≥ 60 years, or underweight.


Assuntos
Enteroscopia de Balão/efeitos adversos , Obstrução Intestinal/etiologia , Adolescente , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Constrição Patológica , Feminino , Humanos , Obstrução Intestinal/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Índice de Gravidade de Doença , Magreza/complicações , Adulto Jovem
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