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1.
Environ Sci Technol ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38934384

RESUMO

Clay minerals are ubiquitous in subsurface environments and have long been recognized as having a limited or negligible impact on the fate of arsenic (As) due to their negatively charged surfaces. Here, we demonstrate the significant role of kaolinite (Kln), a pervasive clay mineral, in enhancing As(V) immobilization during ferrous iron (Fe(II)) oxidation at near-neutral pH. Our results showed that Fe(II) oxidation alone was not capable of immobilizing As(V) at relatively low Fe/As molar ratios (≤2) due to the generation of Fe(III)-As(V) nanocolloids that could still migrate easily as truly dissolved As did. In the presence of kaolinite, dissolved As(V) was significantly immobilized on the kaolinite surfaces via forming Kln-Fe(III)-As(V) ternary precipitates, which had large sizes (at micrometer levels) to reduce the As mobility. The kaolinite-induced heterogeneous pathways for As(V) immobilization involved Fe(II) adsorption, heterogeneous oxidation of adsorbed Fe(II), and finally heterogeneous nucleation/precipitation of Fe(III)-As(V) phases on the edge surfaces of kaolinite. The surface precipitates were mixtures of amorphous basic Fe(III)-arsenate and As-rich hydrous ferric oxide. Our findings provide new insights into the role of clay minerals in As transformation, which is significant for the fate of As in natural and engineered systems.

2.
Environ Geochem Health ; 46(5): 165, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38592368

RESUMO

Soil pollution around Pb-Zn smelters has attracted widespread attention around the world. In this study, we compiled a database of eight potentially toxic elements (PTEs) Pb, Zn, Cd, As, Cr, Ni, Cu, and Mn in the soil of Pb-Zn smelting areas by screening the published research papers from 2000 to 2023. The pollution assessment and risk screening of eight PTEs were carried out by geo-accumulation index (Igeo), potential ecological risk index (PERI) and health risk assessment model, and Monte Carlo simulation employed to further evaluate the probabilistic health risks. The results suggested that the mean values of the eight PTEs all exceeded the corresponding values in the upper crust, and more than 60% of the study sites had serious Pb and Cd pollution (Igeo > 4), with Brazil, Belgium, China, France and Slovenia having higher levels of pollution than other regions. Besides, PTEs in smelting area caused serious ecological risk (PERI = 10912.12), in which Cd was the main contributor to PREI (86.02%). The average hazard index (HI) of the eight PTEs for adults and children was 7.19 and 9.73, respectively, and the average value of total carcinogenic risk (TCR) was 4.20 × 10-3 and 8.05 × 10-4, respectively. Pb and As are the main contributors to non-carcinogenic risk, while Cu and As are the main contributors to carcinogenic risk. The probability of non-carcinogenic risk in adults and children was 84.05% and 97.57%, while carcinogenic risk was 92.56% and 79.73%, respectively. In summary, there are high ecological and health risks of PTEs in the soil of Pb-Zn smelting areas, and Pb, Cd, As and Cu are the key elements that cause contamination and risk, which need to be paid attention to and controlled. This study is expected to provide guidance for soil remediation in Pb-Zn smelting areas.


Assuntos
Cádmio , Chumbo , Adulto , Criança , Humanos , Chumbo/toxicidade , Carcinogênese , Carcinógenos , Poluição Ambiental , Probabilidade , Medição de Risco , Solo , Zinco
3.
Mycoses ; 65(2): 152-163, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34882852

RESUMO

BACKGROUND: An increasing number of cases of invasive pulmonary aspergillosis (IPA) complicating influenza have been described. We performed a meta-analysis to estimate the incidence, risk factors and outcomes of IPA in patients with influenza. METHODS: A systematic search was conducted in the PubMed, EMBASE and Cochrane Library databases from their inception to 31 August 2021 for eligible studies. Data on the incidence and risk factors of and mortality due to IPA in influenza patients were pooled using a random-effects model. Sensitivity analyses restricted to severe influenza requiring intensive care unit (ICU) support and multiple subgroup analyses were performed. RESULTS: Fourteen studies involving 6024 hospitalised patients with influenza were included. IPA was estimated to occur in 10% of influenza patients, with a mortality rate of 52%. Similar incidence (11%) and mortality (54%) estimates for IPA were observed in the sensitivity analysis including severe cases requiring ICU support. Subgroup analysis by geographical location showed a similar IPA rate between European (10%) and non-European (11%) studies. The IPA rate in the subset of nine studies using the modified AspICU criteria was 13%. Most subgroup analyses showed ≥50% mortality in IPA patients. Several predictors for IPA susceptibility were identified, including male sex, smoking history, chronic lung disease, influenza A (H1N1), severe conditions requiring supportive therapy, corticosteroid use before admission, solid organ transplant and haematological malignancy. CONCLUSIONS: The IPA is common in individuals with severe influenza, and the prognosis is particularly poor. Influenza patients, especially those with high-risk factors, should be thoroughly screened for IPA.


Assuntos
Influenza Humana , Aspergilose Pulmonar Invasiva , Humanos , Incidência , Vírus da Influenza A Subtipo H1N1 , Influenza Humana/epidemiologia , Aspergilose Pulmonar Invasiva/epidemiologia , Aspergilose Pulmonar Invasiva/mortalidade , Estudos Retrospectivos , Fatores de Risco
4.
Appl Opt ; 60(26): 7858-7868, 2021 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-34613044

RESUMO

An unsupervised single-image dehazing method using a multiple scattering model is proposed. The method uses an undegraded atmospheric multiple scattering model and unsupervised learning to implement dehazing on single real-world image. The atmospheric multiple scattering model can avoid the influence of multiple scattering on the image and the unsupervised neural network can avoid the intensive operation on the data set. In this method, three unsupervised learning branches and a blur kernel estimation module estimate the scene radiation layer, transmission layer, atmospheric light layer, and blur kernel layer, respectively. In addition, the unsupervised loss function is constructed by prior knowledge to constrain the unsupervised branches. Finally, the output of the three unsupervised branches and the blur kernel estimation module synthesizes the haze image in a self-supervised way. A large number of experiments show that the proposed method has good performance in image dehazing compared with the six most advanced dehazing methods.

5.
Environ Sci Technol ; 53(15): 9034-9044, 2019 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-31264414

RESUMO

Biochars have demonstrated great potential for water decontamination and soil remediation; however, their redox reactivity toward trace contaminants and the corresponding redox-active moieties (RAMs, i.e., phenolic -OH, semiquinone-type persistent free radicals (PFRs), and quinoid C═O) remain poorly understood. Here we investigated the roles of the RAMs on biochar in oxidation of As(III) under varying pH and O2 conditions. The results showed that the promoted oxidation of As(III) by the RAMs is strongly pH dependent. Under acidic and neutral conditions, only the oxidation of As(III) by •OH and H2O2 produced from activation of O2 by phenolic -OH and semiquinone-type PFRs occurred. In contrast, the oxidation by semiquinone-type PFRs, quinoid C═O, and H2O2 (if O2 was introduced) appeared under alkaline conditions. This pH-dependent oxidation behavior was attributed to the varying redox activities of RAMs, as confirmed by multiple characterization and validation experiments using biochar with tuned RAMs compositions, as well as thermodynamics evaluation. Our findings provide new insights into the roles of the RAMs on biochar in the promoted oxidation of trace As(III) over a broader pH range under both anoxic and oxic conditions. This study also paves a promising way to oxidize As(III) with biochar.


Assuntos
Arsênio , Oryza , Carvão Vegetal , Peróxido de Hidrogênio , Concentração de Íons de Hidrogênio , Oxirredução
6.
Environ Sci Technol ; 52(21): 12624-12632, 2018 11 06.
Artigo em Inglês | MEDLINE | ID: mdl-30351041

RESUMO

Cadmium (Cd) in soil was stabilized using copper loaded attapulgite (Cu/ATP) in a microwave (MW) system. Excellent Cd stability in soil was achieved with Cu/ATP addition due to higher adsorption energy (1.38 eV) of Cu/ATP for Cd than that of ATP (∼1 eV), confirmed by density functional theory calculations. The strong hybridization of the s, p-orbitals of Cd with the s, p, d-orbitals of Cu on ATP contributed to the strong interactions between Cd and Cu/ATP. The stability performance of Cd in Cu/ATP-treated soil was further enhanced after MW irradiation through a series of phase transformation to more stable Cd-bearing crystalline minerals. The transformation was initiated by MW-induced "hot spots", which created cationic vacancy on Cu/ATP surface and enhanced the solid-state reactions between Cd and Cu/ATP framework. The total bond orders of Cd in the formed CdAl4O7 crystalline mineral elevated to 3.38, which was 5-fold higher than that for Cd on Cu/ATP, ensuring the long-term stability of Cd even after 360 curing days. Cd contaminated soil from a former industrial electroplating site was successfully stabilized with the proposed strategy. The research provides an effective stabilization strategy as well as a comprehensive understanding of the mechanism of long-term Cd stabilization.


Assuntos
Cádmio , Poluentes do Solo , Cobre , Compostos de Magnésio , Micro-Ondas , Compostos de Silício
7.
J Cell Mol Med ; 20(11): 2148-2159, 2016 11.
Artigo em Inglês | MEDLINE | ID: mdl-27374973

RESUMO

Gastric cancer is the fourth most common cancer in the world. The clinical applications of both chemotherapy and targeted drugs are limited because of the complexity of gastric cancer. In this study, sulforhodamine B, colony formation assay, 4',6-diamidino-2-phenylindole (DAPI) stain, flow cytometry were used to determine the in vitro cytotoxicity, apoptosis and mitochondrial membrane potential of gastric cancer AGS and HGC-27 cells before and after treatment. Real-time PCR and Western blot were used to analyse the mRNA transcription and protein expression respectively. Confocal microscopy was used to determine the localization of target protein within the cells. Treatment with the combination of ABT-737 and 2,5-dimethyl-celecoxib (DMC) showed strong synergistic effect in both AGS and HGC-27 cells. Moreover, DMC would not influence the intracellular prostaglandin E2 (PGE2) level, thus lacking the toxicity profile of celecoxib. Interestingly, given the significant synergistic effect, combination treatment did not affect the protein expression of BH-3 proteins including Puma, Noxa and Bim. In combination treatment, cell apoptosis was found independent of caspase-3 activation. The translocation of apoptosis-inducing factor (AIF) from mitochondrion to nuclear was responsible for the induced apoptosis in the combination treatment. Taken together, this study provided a novel combination treatment regimen for gastric cancer. Furthermore, the existence of caspase-independent apoptotic pathway induced by treatment of ABT-737 was not yet seen until combined with DMC, which shed light on an alternative mechanism involved in Bcl-2 inhibitor-induced apoptosis.


Assuntos
Fator de Indução de Apoptose/metabolismo , Compostos de Bifenilo/farmacologia , Celecoxib/farmacologia , Núcleo Celular/metabolismo , Nitrofenóis/farmacologia , Pirazóis/farmacologia , Neoplasias Gástricas/patologia , Sulfonamidas/farmacologia , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Linhagem da Célula/efeitos dos fármacos , Núcleo Celular/efeitos dos fármacos , Sinergismo Farmacológico , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Piperazinas/farmacologia , Transporte Proteico/efeitos dos fármacos
8.
Acta Pharmacol Sin ; 37(12): 1597-1605, 2016 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27665846

RESUMO

AIM: Deacetylisovaltratum (DI) is isolated from the traditional Chinese herbal medicine Patrinia heterophylla Bunge, which exhibits anti-cancer activity. Here, we investigated the effects of DI on human gastric carcinoma cell lines in vitro and elucidated its anti-cancer mechanisms. METHODS: Human gastric carcinoma AGS and HGC-27 cell lines were treated with DI, and cell viability was detected with MTT assay. Cell cycle stages, apoptosis and mitochondrial membrane potential were measured using flow cytometry. Protein levels were analyzed by Western blotting. Tubulin polymerization assays and immunofluorescence were used to characterize the tubulin polymerization process. RESULTS: DI inhibited the cell viability of AGS and HGC-27 cells in a dose- and time-dependent manner with IC50 values of 12.0 and 28.8 µmol/L, respectively, at 24 h of treatment. Treatment with DI (10-100 µmol/L) dose-dependently promoted tubulin polymerization, and induced significant G2/M cell cycle arrest in AGS and HGC-27 cells. Moreover, DI treatment disrupted mitochondrial membrane potential and induced caspase-dependent apoptosis in AGS and HGC-27 cells. CONCLUSION: DI induces G2/M-phase arrest by disrupting tubulin polymerization in human gastric cancer cells, which highlights its potent anti-cancer activity and potential application in gastric cancer therapy.


Assuntos
Antineoplásicos/farmacologia , Pontos de Checagem da Fase G2 do Ciclo Celular/efeitos dos fármacos , Neoplasias Gástricas/tratamento farmacológico , Moduladores de Tubulina/farmacologia , Antineoplásicos/química , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Potenciais da Membrana/efeitos dos fármacos , Tubulina (Proteína)/química , Moduladores de Tubulina/química
10.
ISA Trans ; 150: 278-297, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38782640

RESUMO

Marine intelligent net tank aquaculture monitoring plays an important role in improving aquaculture efficiency, environmental monitoring efficiency, and environmental safety. The underwater environment has complex light, often with problems such as scattering and absorption, resulting in poor image quality, making it difficult to accurately analyze and judge the aquaculture environment. Improving marine intelligent net tank aquaculture monitoring has the following three advantages: 1) better observation and monitoring of the aquaculture process, timely detection of problems and abnormalities, to protect the benefits of aquaculture and product quality. 2) more convenient and rapid monitoring of the aquaculture environment, improving monitoring efficiency and reducing monitoring costs. 3) effective monitoring of the underwater environment around the farm, and timely detection of foreign pollution, harmful substances, and other problems, to protect the safety of the aquaculture environment. Therefore, in order to solve the two degradation problems of scattering and absorption in the process of marine smart net farm monitoring, we propose a marine smart net farm monitoring method using multiple scattering models and multiple spatial transformations, called MINM. Specifically, inspired by the image chromatic aberration correction method, we design a color correction method in the multicolor space, which is implemented by using the Lab and RGB color space by performing contrast-constrained adaptive histogram equalization and gray world assumptions, respectively, to correct color shifts in different color models. Based on this, we propose a de-scattering method using a multi-scattering model, which eliminates the effect of scattering on underwater imaging by embedding a complete multi-scattering underwater imaging model to guide the extraction of different features in the multi-scattering model. To obtain more qualified results, we also propose an efficient perceptual fusion to mix the output of the de-scattering and color correction. Thus, our method can take advantage of multiple scattering models and multiple spatial transformations to effectively improve the visual quality of underwater images, producing enhanced results that fit the complete underwater imaging model and have bio-visual characteristics. In extensive experimental demonstrations, our MINM method has shown higher performance than the state-of-the-art methods in terms of both visual quality and quantitative metrics. All experimental results and datasets in this paper are available from the following website: https://github.com/An-Shunmin/MINM.

11.
Environ Sci Pollut Res Int ; 31(18): 27286-27303, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38507168

RESUMO

Data mining by machine learning (ML) has recently come into application in heavy metals purification from wastewater, especially in exploring lead removal by biochar that prepared using tube furnace (TF-C) and fluidized bed (FB-C) pyrolysis methods. In this study, six ML models including Random Forest Regression (RFR), Gradient Boosting Regression (GBR), Support Vector Regression (SVR), Kernel Ridge Regression (KRR), Extreme Gradient Boosting (XGB), and Light Gradient Boosting Machine (LGBM) were employed to predict lead adsorption based on a dataset of 1012 adsorption experiments, comprising 422 TF-C groups from our experiments and 590 FB-C groups from literatures. The XGB model showed superior accuracy and predictive performance for adsorption, achieving R2 values for TF-C (0.992) and FB-C (0.981), respectively. Contrasting inferior results were observed in other models, including RF (0.962 and 0.961), GBR (0.987 and 0.975), SVR (0.839 and 0.763), KRR (0.817 and 0.881), and LGBM (0.975 and 0.868). Additionally, a hybrid dataset combining both biochars in Pb adsorption also indicated high accuracy (0.972) as obtained from XGB model. The investigation revealed that the influence of char characteristics and adsorption conditions on Pb adsorption differs between the two biochar. Specific char characteristics, particularly nitrogen content, significantly influence lead adsorption in both biochar. Interestingly, the influence of pyrolysis temperature (PT) on lead adsorption is found to be greater for TF-C than for FB-C. Consequently, careful consideration of PT is crucial when preparing TF-C biochar. These findings offer practical guidance for optimizing biochar preparation conditions during heavy metal removal from wastewater.


Assuntos
Carvão Vegetal , Chumbo , Aprendizado de Máquina , Carvão Vegetal/química , Chumbo/química , Adsorção , Poluentes Químicos da Água/química
12.
Sci Total Environ ; 940: 173536, 2024 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-38802006

RESUMO

Soil organic matter (SOM) and clay minerals are important sinks for reactive heavy metals (HMs) and exogenous hydrogen ions (H+). Therefore, HMs are likely to be released into soil porewater under acid rainfall conditions due to the competitive adsorption of H+. However, negligible Lead, Zinc, and Cadmium (<6 ‰) in the Pb/Zn smelter soil were leached, and the effects of SOM and clay minerals on HMs leaching were unclear. Herein, the H+ consumption and HMs redistribution on SOM and clay minerals were quantitated by the multi-surface model and density functional theory calculations to reveal the roles of SOM and clay minerals in alleviating HMs' leaching. Clay minerals consumed 43.2 %-52.0 % of the exogenous H+, serving as the dominant sink for the exogenous H+ due to its high content and hindering H+ competitive adsorption on SOM. Protonation of the functional groups constituted >90 % of the total H+ captured by clay minerals. Meanwhile, some H+ also competed with HMs for adsorption sites on clay minerals due to its 0.497-fold to 1.54-fold higher binding energies than HMs, resulting in the release of HMs. On the contrary, SOM served as an accommodator for taking over the released HMs from clay minerals. The HMs complexation on the low-affinity sites (R-L-) of SOM was responsible for the recapture of HMs. In Ca-enriched soil, the released HMs were also recaptured by SOM via ion exchange on the R-L-Ca+ and the high-affinity sites (R-H-Ca+) sites due to the 30.8 %-178 % higher binding energies of HMs on these sites than those of Ca. As a result, >63.4 % of the released HMs from clay minerals were transferred to the SOM. Thus, the synergy of SOM and clay minerals in alleviating the leaching of HMs in Pb/Zn smelter soils cannot be ignored in risk assessment and soil remediation.

13.
BMC Genomics ; 14: 186, 2013 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-23496955

RESUMO

BACKGROUND: Microsporidian Nosema bombycis has received much attention because the pébrine disease of domesticated silkworms results in great economic losses in the silkworm industry. So far, no effective treatment could be found for pébrine. Compared to other known Nosema parasites, N. bombycis can unusually parasitize a broad range of hosts. To gain some insights into the underlying genetic mechanism of pathological ability and host range expansion in this parasite, a comparative genomic approach is conducted. The genome of two Nosema parasites, N. bombycis and N. antheraeae (an obligatory parasite to undomesticated silkworms Antheraea pernyi), were sequenced and compared with their distantly related species, N. ceranae (an obligatory parasite to honey bees). RESULTS: Our comparative genomics analysis show that the N. bombycis genome has greatly expanded due to the following three molecular mechanisms: 1) the proliferation of host-derived transposable elements, 2) the acquisition of many horizontally transferred genes from bacteria, and 3) the production of abundnant gene duplications. To our knowledge, duplicated genes derived not only from small-scale events (e.g., tandem duplications) but also from large-scale events (e.g., segmental duplications) have never been seen so abundant in any reported microsporidia genomes. Our relative dating analysis further indicated that these duplication events have arisen recently over very short evolutionary time. Furthermore, several duplicated genes involving in the cytotoxic metabolic pathway were found to undergo positive selection, suggestive of the role of duplicated genes on the adaptive evolution of pathogenic ability. CONCLUSIONS: Genome expansion is rarely considered as the evolutionary outcome acting on those highly reduced and compact parasitic microsporidian genomes. This study, for the first time, demonstrates that the parasitic genomes can expand, instead of shrink, through several common molecular mechanisms such as gene duplication, horizontal gene transfer, and transposable element expansion. We also showed that the duplicated genes can serve as raw materials for evolutionary innovations possibly contributing to the increase of pathologenic ability. Based on our research, we propose that duplicated genes of N. bombycis should be treated as primary targets for treatment designs against pébrine. The genome data and annotation information of N. bombycis and N.antheraeae were submitted to GenBank (Accession numbers ACJZ01000001 -ACJZ01003558).


Assuntos
Bombyx/genética , Duplicação Gênica , Interações Hospedeiro-Parasita/genética , Microsporídios/genética , Animais , Sequência de Bases , Bombyx/parasitologia , Elementos de DNA Transponíveis , Transferência Genética Horizontal , Genômica , Microsporídios/patogenicidade , Anotação de Sequência Molecular , Dados de Sequência Molecular
14.
Eukaryot Cell ; 11(2): 229-37, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22140229

RESUMO

Microsporidia are a group of eukaryotic intracellular parasites that infect almost all vertebrates and invertebrates. The microsporidian invasion process involves the extrusion of a unique polar tube into host cells. Both the spore wall and the polar tube play an important role in microsporidian pathogenesis. So far, five spore wall proteins (SWP1, SWP2, Enp1, Enp2, and EcCDA) from Encephalitozoon intestinalis and Encephalitozoon cuniculi and five spore wall proteins (SWP32, SWP30, SWP26, SWP25, and NbSWP5) from the silkworm pathogen Nosema bombycis have been identified. Here we report the identification and characterization of a spore wall protein (SWP5) with a molecular mass of 20.3 kDa in N. bombycis. This protein has low sequence similarity to other eukaryotic proteins. Immunolocalization analysis showed SWP5 localized to the exospore and the region of the polar tube in mature spores. Immunoprecipitation, mass spectrometry, and immunofluorescence analyses revealed that SWP5 interacts with the polar tube proteins PTP2 and PTP3. Anti-SWP5 serum pretreatment of mature spores significantly decreased their polar tube extrusion rate. Taken together, our results show that SWP5 is a spore wall protein localized to the spore wall and that it interacts with the polar tube, may play an important role in supporting the structural integrity of the spore wall, and potentially modulates the course of infection of N. bombycis.


Assuntos
Parede Celular/química , Proteínas Fúngicas/química , Nosema/crescimento & desenvolvimento , Esporos Fúngicos/metabolismo , Parede Celular/metabolismo , Imunofluorescência , Proteínas Fúngicas/metabolismo , Peso Molecular
15.
J Ultrasound Med ; 32(7): 1227-32, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23804345

RESUMO

OBJECTIVES: This study aimed to establish reference ranges for Doppler parameters of the fetal dorsalis pedis artery and to compare them with those of the anterior tibial artery. METHODS: Dorsalis pedis artery velocimetry was performed in 138 singleton fetuses. Intraobserver repeatability coefficients and differences between measurements of bilateral legs were also evaluated. Comparisons were made between the pulsatility index in the dorsalis pedis and anterior tibial arteries. RESULTS: The average maximum velocity of the dorsalis pedis artery increased from approximately 12.2 cm/s at 18 weeks' gestation to 33.6 cm/s at 39 weeks' gestation, whereas the minimum velocity did not show any significant variation during the observed gestational weeks. The average pulsatility index increased from about 2.0 at 18 weeks' gestation to 3.1 at 39 weeks' gestation. The pulsatility index was lower in the dorsalis pedis artery than in the anterior tibial artery. CONCLUSIONS: Doppler parameters of the dorsalis pedis artery can be easily and accurately acquired by trained examiners and therefore are potential means for evaluating related fetal vascular development. However, it is still unclear whether changes exist in fetuses with limb diseases, and further investigation is needed.


Assuntos
Artérias/embriologia , Artérias/fisiologia , Ecocardiografia Doppler em Cores/estatística & dados numéricos , Pé/irrigação sanguínea , Pé/embriologia , Segundo Trimestre da Gravidez/psicologia , Terceiro Trimestre da Gravidez/fisiologia , Fluxo Pulsátil/fisiologia , Artérias/diagnóstico por imagem , Velocidade do Fluxo Sanguíneo , China/epidemiologia , Feminino , Humanos , Masculino , Gravidez , Valores de Referência , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
16.
Medicine (Baltimore) ; 102(15): e33544, 2023 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-37058023

RESUMO

This study aimed to compare the clinical effects of the Medis flexible laryngeal mask airway (FLMA) with those of the Ambu AuraFlex FLMA in pediatric ophthalmic surgery. A total of 80 patients, aged 1 to 5 years, in American Society of Anesthesiologists I-II, weighing ≥10 kg, and without any existing airway difficulties, were enrolled in this study. The patients were randomly divided into Group M (Medis FLMA) and Group A (Ambu AuraFlex FLMA). The time of insertion, number of attempts, finger assistance required, manipulation, oropharyngeal leak pressure (OLP), fiberoptic grade of view, and complications such as bloodstaining, hoarseness, and sore throat were recorded. Group M showed a significantly higher OLP than did Group A (P = .002); however, Group M required more finger assistance than did Group A (P = .009). There were no statistically significant differences between the 2 groups in terms of insertion time, number of attempts, manipulation, fiberoptic view grade, or complications. Both the Medis and Ambu AuraFlex FLMA can provide smooth ventilation during pediatric ophthalmic surgeries. The Medis FLMA showed a higher OLP than did the Ambu AuraFlex FLMA but required more finger assistance during insertion.


Assuntos
Máscaras Laríngeas , Humanos , Criança , Máscaras Laríngeas/efeitos adversos , Estudos Retrospectivos , Intubação Intratraqueal , Orofaringe , Respiração
17.
PLoS One ; 18(11): e0293424, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37956194

RESUMO

An in-depth study on the fixed-time event-triggered obstacle avoidance consensus control in heterogeneous USV-AUV systems with input delay and uncertain disturbances are conducted in this paper. When initial state of the system fails to achieve consensus, the desired heterogeneous USV-AUV formation can be achieved by fixed-time consensus control, within a fixed predetermined time, regardless of the initial states. Besides, an event-triggered communication strategy among the agents is introduced in the system, significantly reducing communication energy consumption. By employing the proposed control strategy, the Zeno behavior also can be avoided. Additionally, an obstacle avoidance control algorithm for the heterogeneous USV-AUV system based on improved artificial potential fields (IAPF) is designed, which helps in avoiding both static and dynamic obstacles. Compared to existing research, this algorithm reduces control input jitter, resulting in smoother obstacle avoidance paths. Through extensive simulation experiments and comparisons with other methods, effectiveness and superiority of the proposed algorithm is validated.


Assuntos
Algoritmos , Comunicação , Fatores Desencadeantes , Simulação por Computador , Consenso
18.
Heliyon ; 9(4): e15087, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37128309

RESUMO

This work uses rice husk to fabricate mesoporous silica nanoparticles (D-RMN) for breast cancer therapy. The biocompatible dual-responsive (DAN-RMN) was developed by polymerizing acrylic acid (AA) and n-isopropyl acrylamide (NIPAM) on the DV-RMN surface monomeric ratio to increase drug delivery efficiency after vinyl groups were added to the surface of nanoparticles (DAN-RMN). Various analytical and spectroscopical methods characterized the fabricated nanoparticles. Additionally, further encapsulation with SN-38 into the DAN-RMN enhances anticancer efficiency. The in-vitro controlled SN-38 release displayed remarkable temperature and pH response. The MTT assay established the biocompatibility and cytotoxicity of natural sources of silica and DAN-RMN. The fabricated SN-38@DAN-RMN nanoparticles effectively killed the MDA-MB-231 and 4T1 cancerous cells, confirmed by the MTT assay. The IC50 values of SN-38@DAN-RMN in MDA-MB-231 and 4T1 for 1.8 µg/mL and 1.7 µg/mL, respectively. In addition, acridine orange-ethidium bromide (AO-EB) dual staining methods were used to determine morphological changes of cell shrinkage and fragmentation. Nuclear staining methods confirmed the nuclear fragmentation and condensation of the cells. Further, the cell death was examined using dual staining Annexin V-FITC/PI in flow cytometric analyses to assess apoptosis in the MDA-MB-231 and 4T1 cell lines. The apoptotic cell ratio of SN-38@DAN-RMN in MDA-MB-231 and 4T1 for 27.8 and 32.8, respectively. Since there is no drug leakage in the blood while the carrier is in circulation, the DAN-RMN nanocarrier may be used for targeted and stimuli-responsive administration using ultrasound imaging.

19.
Exp Ther Med ; 26(2): 373, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37415836

RESUMO

Corneal epithelial abnormality is a common manifestation of diabetic keratopathy and leads to delayed epithelial wound healing. The Wnt/ß-catenin signaling pathway participates in the development, differentiation and stratification of corneal epithelial cells. The present study compared the expression of Wnt/ß-catenin signaling pathway related factors, including Wnt7a, ß-catenin, cyclin D1 and phosphorylated (p-) glycogen synthase kinase 3 ß (Gsk3b) between normal and diabetic mouse corneas, by reverse transcription-quantitative PCR, western blotting and immunofluorescence staining. It was found that the expression of the Wnt/ß-catenin signaling pathway related factors was downregulated in diabetic corneas. Upon corneal epithelium scraping, the wound healing rate was significantly increased in diabetic mice after topical treatment with lithium chloride. After further investigation, significantly upregulated levels of Wnt7a, ß-catenin, cyclin D1 and p-Gsk3b were found in the diabetic group 24 h after treatment, accompanied by ß-catenin nuclear translocation observed by immunofluorescence staining. These results suggest that active Wnt/ß-catenin pathway can promote diabetic corneal epithelial wound healing.

20.
Huan Jing Ke Xue ; 44(6): 3450-3462, 2023 Jun 08.
Artigo em Zh | MEDLINE | ID: mdl-37309962

RESUMO

To explore the pollution characteristics and sources of heavy metals in atmospheric deposition in a typical lead-zinc smelting city, 511 effective atmospheric deposition samples from 22 points in different functional areas of a city in Henan Province were collected monthly during 2021. The concentrations and spatial-temporal distribution of heavy metals were analyzed. The geo-accumulation index method and health risk assessment model were utilized to evaluate the heavy metal pollution degree. The sources of heavy metals were quantitatively analyzed using a positive matrix factorization (PMF) model. The results showed that the average concentrations of ω(Pb), ω(Cd), ω(As), ω(Cr), ω(Cu), ω(Mn), ω(Ni), and ω(Zn) in atmospheric deposition samples were 3185.77, 78.18, 273.67, 149.50, 453.60, 810.37, 54.38, and 2397.38 mg·kg-1, respectively, which were all higher than the soil background values of Henan Province. All heavy metals except Mn had significant seasonal variation characteristics. The concentrations of Pb, Cd, As, and Cu in the industrial area with lead-zinc smelting were significantly higher than those in other functional areas, and the concentration of Zn was the highest in the residential mixed area. The results of the geo-accumulation index showed that the pollution of Cd and Pb were the most serious, followed by that of Zn, Cu, and As, which belonged to the serious-extreme pollution category. The main exposure route of non-carcinogenic risk was hand-mouth intake. Pb and As posed the greatest non-carcinogenic risk to children in all functional areas. The carcinogenic risks of Cr, As, Cd, and Ni through the respiratory system to humans were all below the threshold values. The analysis of the PMF model showed that the main sources of heavy metals in atmospheric deposition were industrial pollution sources (39.7%), transportation sources (28.9%), secondary dust sources (14.4%), incineration and coal combustion sources (9.3%), and natural sources (7.8%).

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