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1.
Environ Res ; 242: 117817, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043892

RESUMO

In this study, lanthanum carbonate (LC) was selected as a capping agent to examine its effectiveness in immobilizing sediment internal phosphorus (P), arsenic (As) and tungsten (W). With a 180-day incubation experiment, it was determined that LC capping efficiently reduced the concentrations of soluble reactive P (SRP), soluble As and soluble W in pore water, with the highest reduction rate of 83.39%, 56.21% and 68.52%, respectively. The primary mechanisms involved in the adsorption of P, As and W by LC were precipitation reactions and ligand exchange. Additionally, P, As and W were immobilized by LC capping through the transformation of fractions from mobile and less stable forms to more stable forms. Furthermore, LC capping led to an increase in the Eh value, which promoted the oxidation of soluble Fe (Ⅱ) and soluble Mn. The significantly positive correlation and synchronized variations observed between SRP, soluble As, soluble W, and soluble Fe (II) indicated that the effects of LC on Fe redox played a crucial role in immobilizing sediment internal P, As and W. However, the oxidation of Mn, promoted by LC, played a more significant role in immobilizing sediment internal As than P and W. These effects resulted in LC capping achieving the highest reduction of SRP, soluble As and soluble W flux at 145.22, 22.19, and 0.58 µg m-2d-1. It is of note that LC capping did not lead to an elevated release hazard of Co, Ni, Cu, and Pb, barring Cd. Besides, LC capping did not modify the entire microbial communities in the sediment, but altered the proportional representation of specific microorganisms. Generally, LC has potential as a capping agent capable of simultaneously immobilizing sediment internal P, As and W.


Assuntos
Arsênio , Lantânio , Poluentes Químicos da Água , Poluentes Químicos da Água/análise , Tungstênio , Fósforo , Sedimentos Geológicos , Lagos
2.
Plant Cell Environ ; 46(12): 3748-3759, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37651619

RESUMO

The ecological mechanism underlying nocturnal stomatal conductance (gsn ) in C3 and C4 plants remains elusive. In this study, we proposed a 'coordinated leaf trait' hypothesis to explain gsn in rice plants. We conducted an open-field experiment by applying drought, nutrient stress and the combined drought-nutrient stress. We found that gsn was neither strongly reduced by drought nor consistently increased by nutrient stress. With the aforementioned multiple abiotic stressors considered as random effects, gsn exhibited a strong positive correlation with dark respiration (Rn ). Notably, gsn primed early morning (5:00-7:00) photosynthesis through faster stomatal response time. This photosynthesis priming effect diminished after mid-morning (9:00). Leaves were cooled by gsn -derived transpiration. However, our results clearly suggest that evaporative cooling did not reduce dark respiration cost. Our results indicate that gsn is more closely related to carbon respiration and assimilation than water and nutrient availability, and that dark respiration can explain considerable variation of gsn .


Assuntos
Oryza , Oryza/fisiologia , Secas , Folhas de Planta/fisiologia , Fotossíntese/fisiologia , Respiração , Água/fisiologia , Transpiração Vegetal/fisiologia
3.
Environ Res ; 216(Pt 3): 114689, 2023 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-36323350

RESUMO

Submerged plants and lanthanum-modified bentonite (LMB) have important applications for the remediation of contaminated sediments; however, their combined effect on arsenic (As) removal has not been comprehensively evaluated. In this study, the physicochemical properties and changes in soluble As in sediments treated with LMB, Vallisneria spiralis (V. spiralis), and LMB + V. spiralis were observed at three time points (days 15, 35, and 66), and the changes in microbial and As species in sediments on day 66 were analyzed. LMB + V. spiralis treatment was the most effective for As removal. On day 66, the average concentrations of soluble As at a depth of 0-100 mm decreased by 12.71%, 48.81%, and 59.73% following treatment with LMB, V. spiralis, and LMB + V. spiralis, respectively. Further analysis showed that LMB is more effective at removing As(V) than V. spiralis, while V. spiralis is more effective at removing As(III), and the combination of LMB + V. spiralis is more effective for removing both As(III) and As(V) than individual LMB and V. spiralis treatments. LMB + V. spiralis enhanced the transformation of mobile As to Fe2O3/oxyhydroxide-bound As in sediments and the activity of As-oxidizing microorganisms. LMB promoted the growth of V. spiralis and enhanced the removal of As. This study indicates that this combination is an effective method for removing mobile As from sediments, and could effectively inhibit the release of As from sediments to overlying water.


Assuntos
Arsênio , Hydrocharitaceae , Bentonita/química , Lantânio/química , Sedimentos Geológicos/química , Fósforo/química , Lagos/química
4.
Cardiovasc Diabetol ; 18(1): 3, 2019 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-30630489

RESUMO

BACKGROUND: Epicardial fat tissue (EFT) is the visceral fat distributed along the coronary arteries between the pericardium and the myocardium. Increases in EFT are closely related to the occurrence of diabetes mellitus (DM) and cardiovascular disease. To further understand the link between EFT and DM, we conducted a meta-analysis of the relevant literature. METHODS: We systematically searched electronic databases for studies on EFT performed in DM patients and published up to 30 September 2018. We included data on EFT in a DM patient group and a non-DM control group. We then assessed the effect of DM on EFT by meta-analysis and trial sequential analysis (TSA). All statistical analyses were performed using Stata 12.0 and TSA software. RESULTS: A total of 13 studies (n = 1102 patients) were included in the final analysis. Compared with the control group, DM patients had significantly higher EFT (SMD: 1.23; 95% CI 0.98, 1.48; P = 0.000; TSA-adjusted 95% CI 0.91, 2.13; P < 0.0001). The TSA indicated that the available samples were sufficient and confirmed that firm evidence was reached. According to the regression analysis and subgroup analyses, DM typing, EFT ultrasound measurements, total cholesterol (TC) and triglyceride (TG) levels were confounding factors that significantly affected our results. CONCLUSIONS: Our meta-analysis suggests that the amount of EFT is significantly higher in DM patients than in non-DM patients.


Assuntos
Tecido Adiposo/fisiopatologia , Adiposidade , Diabetes Mellitus/fisiopatologia , Pericárdio/fisiopatologia , Tecido Adiposo/diagnóstico por imagem , Adulto , Idoso , Diabetes Mellitus/diagnóstico por imagem , Diabetes Mellitus/epidemiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Pericárdio/diagnóstico por imagem , Prognóstico , Fatores de Risco , Adulto Jovem
5.
J Environ Manage ; 246: 647-657, 2019 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-31212218

RESUMO

In this long-term field study, to restore a dried river ecosystem, reclaimed water was used as a supplementary water source. The main aim of this study was to investigate the accumulation and migration potential of EDCs in groundwater during long-term utilization of reclaimed water and the changes in microbial community during the removal of EDCs. A long-term field study was conducted in order to ascertain the temporal and spatial distribution of four selected endocrine-disrupting chemicals (EDCs) in an underground aquifer in the Chaobai watershed, where reclaimed water is the primary water source. Anew, the microbial community structure at different groundwater depths, along with related environmental factors were also determined. Based on the results obtained from this long-term study, it was found that the EDCs in the surface water of the Chaobai river have entered a depth of 80 m in the groundwater aquifers, within a distance of 360 m from the river. The vertical profiles of the concentrations of bisphenol A (BPA), 4-nonylphenol (NP), estrone (E1), and estriol (E3) decreased significantly from the surface to different groundwater depths with first-order attenuation rates of 0.0416, 0.0343, 0.0498, and 0.0173 m-1. The aquifer depth, water temperature, conductivity, and coexisting anions correlated well with the distribution of EDCs in groundwater.


Assuntos
Disruptores Endócrinos , Água Subterrânea , Microbiota , Poluentes Químicos da Água , Monitoramento Ambiental , Rios , Água
6.
J Ultrasound Med ; 37(12): 2881-2889, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29689620

RESUMO

OBJECTIVES: To explore the value of transurethral contrast-enhanced ultrasonography (CEUS) in the diagnosis and evaluation of female urethral diverticula. METHODS: This study prospectively enrolled 35 women with periurethral cystic lesions, who underwent preoperative transurethral CEUS at our single center between April 2015 and May 2017. The diagnosis of a urethral diverticulum was made by the detection of microbubbles inside the lesion. Data regarding the structure and ostia of the diverticula were collected and then compared with intraoperative findings. RESULTS: The median (interquartile range) age of the 35 patients was 43 (34-48) years. The most common manifestations were dysuria (43%) and palpable masses (40%). On transurethral CEUS, 20 patients were found to have urethral diverticula. The diverticula involved the proximal, mid, and distal urethra with different sizes. The shapes of the diverticula were simple in 4 patients (20%), U shaped in 8 patients (40%), and circumferential in 8 patients (40%). A total of 23 ostia were identified. Seventeen women (85%) had 1 ostium, and 3 women (15%) had 2 ostia. Twenty-one diverticular ostia (91%) were located from the 3- to 9-o'clock positions. The median (interquartile range) distance from the diverticular ostia to the bladder neck was 20 (9-31) mm. During surgery, all US presentations correlated well with surgical findings, and 21 patients were confirmed to have urethral diverticula. The transurethral CEUS had sensitivity of 95% and specificity of 100%. CONCLUSIONS: Transurethral CEUS is an effective method for identifying the structure and ostium of female urethral diverticula. It may have a potential role in preoperative planning and surgical management.


Assuntos
Meios de Contraste , Divertículo/diagnóstico por imagem , Cuidados Pré-Operatórios/métodos , Doenças Uretrais/diagnóstico por imagem , Adulto , Feminino , Humanos , Aumento da Imagem/métodos , Pessoa de Meia-Idade , Estudos Prospectivos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Ultrassonografia/métodos , Uretra/diagnóstico por imagem , Adulto Jovem
7.
Arch Gynecol Obstet ; 297(4): 943-949, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29350275

RESUMO

OBJECTIVE: To explore the feasibility of three-dimensional (3D) transperineal ultrasound on the observation of paravaginal support in nulliparous and postpartum women. METHODS: Volume datasets were acquired in 50 nulliparous and 100 postpartum women using 3D transperineal ultrasound. Paravaginal supports were observed by studying the vaginal cross-sectional morphology. The extent of paravaginal support in specific level were evaluated by counting out at a 2 mm interval in tomographic ultrasound imaging mode in all subjects. The Mann-Whitney U test were applied to establish comparisons between the two groups. RESULTS: Three representative manifestations of vaginal cross-sectional morphology corresponding to different paravaginal support were presented from the dorsal side to the caudal side, both in nulliparous women and postpartum women. The extent of paravaginal support in middle vagina was 11 slices (range 9-12) in nulliparous women and 7 slices (range 4-10) in postpartum women (P < 0.05). CONCLUSION: This pilot study confirmed that it was feasible to indirectly study paravaginal support by observing the vaginal cross-sectional morphology using 3D transperineal ultrasound.


Assuntos
Imageamento Tridimensional/métodos , Diafragma da Pelve/diagnóstico por imagem , Períneo/diagnóstico por imagem , Ultrassonografia/métodos , Vagina/diagnóstico por imagem , Adulto , Estudos Transversais , Estudos de Viabilidade , Feminino , Humanos , Paridade , Projetos Piloto , Período Pós-Parto , Gravidez
8.
Genome Res ; 24(8): 1308-15, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24721644

RESUMO

The hypoxic environment imposes severe selective pressure on species living at high altitude. To understand the genetic bases of adaptation to high altitude in dogs, we performed whole-genome sequencing of 60 dogs including five breeds living at continuous altitudes along the Tibetan Plateau from 800 to 5100 m as well as one European breed. More than 150× sequencing coverage for each breed provides us with a comprehensive assessment of the genetic polymorphisms of the dogs, including Tibetan Mastiffs. Comparison of the breeds from different altitudes reveals strong signals of population differentiation at the locus of hypoxia-related genes including endothelial Per-Arnt-Sim (PAS) domain protein 1 (EPAS1) and beta hemoglobin cluster. Notably, four novel nonsynonymous mutations specific to high-altitude dogs are identified at EPAS1, one of which occurred at a quite conserved site in the PAS domain. The association testing between EPAS1 genotypes and blood-related phenotypes on additional high-altitude dogs reveals that the homozygous mutation is associated with decreased blood flow resistance, which may help to improve hemorheologic fitness. Interestingly, EPAS1 was also identified as a selective target in Tibetan highlanders, though no amino acid changes were found. Thus, our results not only indicate parallel evolution of humans and dogs in adaptation to high-altitude hypoxia, but also provide a new opportunity to study the role of EPAS1 in the adaptive processes.


Assuntos
Adaptação Fisiológica/genética , Cães/genética , Altitude , Sequência de Aminoácidos , Animais , Sequência de Bases , Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Hipóxia Celular , Análise Mutacional de DNA , Genoma , Sequenciamento de Nucleotídeos em Larga Escala , Dados de Sequência Molecular , Polimorfismo de Nucleotídeo Único
9.
Biochem Biophys Res Commun ; 480(4): 696-701, 2016 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-27983984

RESUMO

Epicardial progenitor cells (EpiCs) have a crucial role in cardiac development and vasculature formation. Here we detected the expression of Angiotensin II (Ang II) receptors AT1 and AT2 on EpiCs and demonstrated that AngII could increase the expression of smooth muscle specific markers, including α-smooth muscle actin (α-SMA) and myosin heavy chain 11 (Myh11) in EpiCs. Moreover, the expression of α-SMA and Myh11 induced by Ang II was blocked by pretreatment of EpiCs with the AT1 receptor antagonist losartan, but not the AT2 receptor antagonist PD123319. We further showed that the AngII-induced cells showed significant contractile responses to carbachol. These results implied that AngII could effectively induce EpiCs to differentiate into vascular smooth muscle-like cells through the AT1 receptor.


Assuntos
Angiotensina II/farmacologia , Diferenciação Celular/efeitos dos fármacos , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/citologia , Miócitos de Músculo Liso/metabolismo , Receptores de Angiotensina/metabolismo , Animais , Técnicas de Cultura Celular por Lotes , Feminino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Liso Vascular/citologia , Músculo Liso Vascular/efeitos dos fármacos , Mioblastos Cardíacos , Miócitos de Músculo Liso/efeitos dos fármacos , Pericárdio/citologia , Pericárdio/efeitos dos fármacos , Pericárdio/metabolismo
10.
ScientificWorldJournal ; 2016: 9157605, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27066529

RESUMO

Staphylococcus aureus is a major causative agent leading to bovine mastitis and has specific phonotypical characteristics including small colony, slow growth, and decreased hemolysis, therefore named as the small colony variants (SCVs). Out of 30 tested samples of the chronic S. aureus cases, one strain of SCVs (S. aureus SCV22) was isolated along with its parental strains (S. aureus11). S. aureus SCV22 showed a slow growth rate when it is compared with the parental strain. However, their resistant patterns were similar. Meanwhile, S. aureus SCV22 depicted the lower rate of apoptosis in bovine mammary epithelial cells. These findings of the present study presented the unique characteristics of S. aureus SCV22 for the first time in Yunnan province, which provided a prophase foundation for further study about the pathogenesis of S. aureus SCVs in chronic mastitis.


Assuntos
Indústria de Laticínios , Mastite Bovina/microbiologia , Staphylococcus aureus/crescimento & desenvolvimento , Staphylococcus aureus/isolamento & purificação , Animais , Antibacterianos/farmacologia , Apoptose/efeitos dos fármacos , Bovinos , China , Contagem de Colônia Microbiana , Feminino , Espaço Intracelular/metabolismo , Testes de Sensibilidade Microbiana , Leite/microbiologia , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/ultraestrutura
11.
BMC Vet Res ; 11: 232, 2015 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-26358082

RESUMO

BACKGROUND: Porcine reproductive and respiratory syndrome virus (PRRSV) is the cause of an economically important swine disease that has devastated the swine industry since the late 1980s. The aim of the present study was to investigate the interaction between reactive oxygen species (ROS) and NF-κB by PRRSV infection. RESULTS: We isolated the local strain of PRRSV from southwest China, designated YN-2011, then sequenced and analyzed the genome. YN-2011 was then used to evaluate the interaction of ROS and NF-κB. In PRRSV infected MARC-145 cells, there was a time-dependent increase in ROS and Maleic Dialdehyde (MDA). Accordingly, NF-κB activation was also increased as PRRSV infection progressed. Degradation of IκB mRNA was detected late in PRRSV infection, and overexpression of the dominant negative form of IκBα significantly suppressed NF-κB induced by PRRSV. CONCLUSIONS: The results indicate that the generation of ROS is involved in PRRSV replication and this progression is associated with the alteration in NF-κB activity induced by ROS. These results should extend our better understanding the interaction between PRRSV and host MARC-145 cells.


Assuntos
NF-kappa B/metabolismo , Síndrome Respiratória e Reprodutiva Suína/virologia , Vírus da Síndrome Respiratória e Reprodutiva Suína/fisiologia , Espécies Reativas de Oxigênio/metabolismo , Animais , Linhagem Celular , China/epidemiologia , Regulação da Expressão Gênica/fisiologia , Genoma Viral , Haplorrinos , NF-kappa B/genética , Síndrome Respiratória e Reprodutiva Suína/epidemiologia , Suínos
12.
J Hazard Mater ; 467: 133644, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38330646

RESUMO

Arsenic (As) is a metalloid that can accumulate in eutrophic lakes and cause adverse health effects to people worldwide. However, the seasonal process and dynamic mechanism for As mobilization in eutrophic lake remains effectively unknown. Here we innovatively used the planar optodes (PO), high-resolution dialysis (HR-Peeper) combined with fluorescence excitation-emission matrix coupled with parallel factor (EEM-PARAFAC) analysis technologies. We synchronously investigate monthly O2, As, iron (Fe), manganese (Mn), and naturally occurring dissolved organic matter (DOM) changes in sediments of Lake Taihu at high resolution in field conditions. We find high As contamination from sediments with 61.88-327.07 µg m-2 d-1 release As fluxes during the algal bloom seasons from May to October 2021. Our results show that an increase in DOM, mainly for humic-like components, resulting in high electron transfer capacity (ETC), promoted the reductive dissolution of Fe and Mn oxides to release As. Partial least square-path modeling (PLS-PM) and random forest modeling analysis identified that Mn oxide reductive dissolution directly accelerated sediments As contamination, which is the crucial factor. Understanding crucial factor controlling As release is especially essential in areas of eutrophic lakes developing effective strategies to manage As-rich eutrophic lake sediments worldwide.


Assuntos
Arsênio , Manganês , Humanos , Matéria Orgânica Dissolvida , Ferro , Lagos
13.
Gene ; 927: 148668, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38852695

RESUMO

Evidence has indicated that Enterococcus plays a vital role in non-alcoholic fatty liver disease (NAFLD) development. However, the microbial genetic basis and metabolic potential in the disease are yet unknown. We previously isolated a bacteria Enterococcus faecium B6 (E. faecium B6) from children with NAFLD for the first time. Here, we aim to systematically investigate the potential of strain B6 in lipogenic effects. The lipogenic effects of strain B6 were explored in vitro and in vivo. The genomic and functional characterizations were investigated by whole-genome sequencing and comparative genomic analysis. Moreover, the metabolite profiles were unraveled by an untargeted metabolomic analysis. We demonstrated that strain B6 could effectively induce lipogenic effects in the liver of mice. Strain B6 contained a circular chromosome and two circular plasmids and posed various functions. Compared to the other two probiotic strains of E. faecium, strain B6 exhibited unique functions in pathways of ABC transporters, phosphotransferase system, and amino sugar and nucleotide sugar metabolism. Moreover, strain B6 produced several metabolites, mainly enriched in the protein digestion and absorption pathway. The unique potential of strain B6 in lipogenic effects was probably associated with glycolysis, fatty acid synthesis, and glutamine and choline transport. This study pioneeringly revealed the metabolic characteristics and specific detrimental traits of strain B6. The findings provided new insights into the underlying mechanisms of E. faecium in lipogenic effects, and laid essential foundations for further understanding of E. faecium-related disease.

14.
Sci Total Environ ; 926: 171400, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38461974

RESUMO

The maximum Rubisco carboxylation rate normalized to 25 °C (Vcmax25) is a key parameter in terrestrial biosphere models for simulating carbon cycling. Recently, global distributions of Vcmax25 have been derived through various methods and different data, including field measurements, ecological optimality theory (EOT), leaf chlorophyll content (LCC), and solar-induced chlorophyll fluorescence (SIF). However, direct validation poses challenges due to high uncertainty arising from limited ground-based observations. This study conducted an indirect evaluation of four Vcmax25 datasets by assessing the accuracy of gross primary productivity (GPP) simulated using the Biosphere-atmosphere Exchange Process Simulator (BEPS) at both site and global scales. Results indicate that, compared to utilizing Vcmax25 fixed by plant functional types (PFT) derived from field measurements, incorporating Vcmax25 derived from SIF and LCC (SIF + LCC), or solely LCC, into BEPS significantly reduces simulated errors in the annual total GPP, with a 23.2 %-25.1 % decrease in the average absolute bias across 196 FLUXNET2015 sites. Daily GPP for evergreen needleleaf forests, deciduous broadleaf forests, shrublands, grasslands, and croplands shows a 7.8 %-27.6 % decrease in absolute bias, primarily attributed to reduced simulation errors during off-peak seasons of vegetation growth. Conversely, the annual total GPP error simulated using EOT-derived Vcmax25 increases slightly (2.2 %) compared to that simulated using PFT-fixed Vcmax25. This is primarily due to a significant overestimation in evergreen broadleaf forests and underestimation in croplands, despite slight increased accuracy for other PFTs. The global annual GPP simulated using Vcmax25 with seasonal variations (i.e., LCC Vcmax25 and SIF + LCC Vcmax25) yields a 4.3 %-7.3 % decrease compared to that simulated using PFT-fixed Vcmax25. Compared to FLUXCOM and GOSIF GPP products, the GPP simulated based on SIF + LCC Vcmax25 and LCC Vcmax25 demonstrates better consistency (R2 = 0.91-0.93, RMSE = 314.2-376.6 g C m-2 yr-1). This study underscores the importance of accurately characterizing the spatiotemporal variations in Vcmax25 for the accurate simulation of global vegetation productivity.


Assuntos
Clorofila , Fotossíntese , Fluorescência , Florestas , Estações do Ano , Plantas , Folhas de Planta , Ecossistema
15.
Am J Ophthalmol ; 262: 178-185, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38360335

RESUMO

PURPOSE: To investigate the correlation between the opening and closing states of anterior chamber angle (ACA) and the density of limbal epithelial basal cells (LEBCs) in subjects with primary angle-closure glaucoma (PACG). DESIGN: Cross-sectional observational study. METHODS: A total of 54 eyes of 29 patients diagnosed with PACG were included in the study. Fifty-four eyes from normal subjects were included as control. Automatic evaluation system for ultrasound biomicroscopy images of anterior chamber angle was used to assist ophthalmologists in identifying the opening or closing state of ACA, and the in vivo confocal microscopy (IVCM) was used to evaluate the density of LEBCs in different directions. RESULTS: (1) The average density of LEBCs in the superior, inferior, nasal, and temporal limbus of the eyes in the PACG group was lower than that in the control group, and this pattern did not align with the density distribution observed in the control group. (2) In the early, moderate and advanced PACG, the density of LEBCs corresponding to the closed angle was lower than that in the control group (P < .05). Compared with the density of LEBCs corresponding to the closed angle and the open angle, the closed angle of PACG in the early, moderate and advanced stages was less than that in the open angle (P < .05 in the early and moderate stages; advanced stage P > .05). (3) The basal cell density was processed by dimensionless analysis. In the data calculated by averaging and minimizing, both closed angle dimensionless values were smaller than the open angle (P < .05). (4) Comparative analysis was conducted among the normal, open-angle, and closed-angle conditions in the superior, inferior, nasal, and temporal limbus. In the early stage of PACG, significant differences were observed in 4 limbal regions (P < .05), while in the moderate PACG stage, this difference was noted in 3 limbal regions (P < .05). In advanced PACG, 2 limbal regions exhibited significant differences (P < .05). These findings suggest that during the early PACG stage, angle closure is the predominant influencing factor on LEBCs density, while in the advanced stage, the decrease in density is attributed to a combination of angle closure and the natural progression of the disease. CONCLUSIONS: There is a significant correlation between anterior chamber angle status and LEBCs. Advanced PACG and angle closure should be highly suspected of the occurrence of limbal stem cell deficiency (LSCD).


Assuntos
Câmara Anterior , Glaucoma de Ângulo Fechado , Pressão Intraocular , Limbo da Córnea , Microscopia Acústica , Microscopia Confocal , Células-Tronco , Humanos , Glaucoma de Ângulo Fechado/diagnóstico , Glaucoma de Ângulo Fechado/fisiopatologia , Estudos Transversais , Limbo da Córnea/patologia , Limbo da Córnea/diagnóstico por imagem , Masculino , Feminino , Pessoa de Meia-Idade , Câmara Anterior/diagnóstico por imagem , Câmara Anterior/patologia , Contagem de Células , Idoso , Células-Tronco/patologia , Pressão Intraocular/fisiologia , Gonioscopia , Deficiência Límbica de Células-Tronco
16.
Environ Pollut ; 342: 123154, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101530

RESUMO

Sulfate concentrations in eutrophic waters continue to increase; however, the transformations of arsenic (As) in sediments under these conditions are unclear. In this study, we constructed a series of microcosms to investigate the effect of algal degradation on As transformations in sediments with high sulfate concentrations. The results showed that both the elevated sulfate levels and algal degradation enhanced the release of As from sediments to the overlying water, and degradation of algal in the presence of elevated sulfate levels could further contribute to As release. Sulfate competed with arsenate for adsorption in the sediments, leading to As desorption, while algal degradation created a strongly anaerobic environment, leading to the loss of the redox layer in the surface sediments. With high sulfate, algal degradation enhanced sulfate reduction, and sulfur caused the formation of thioarsenates, which may cause re-dissolution of the arsenides, enhancing As mobility by changing the As speciation. The results of sedimentary As speciation analysis indicated that elevated sulfur levels and algal degradation led to a shift of As from Fe2O3/oxyhydroxide-bound state to specifically adsorbed state at the sediment water interface. This study indicated that algal degradation increases the risk of As pollution in sulfate-enriched eutrophic waters.


Assuntos
Arsênio , Poluentes Químicos da Água , Arsênio/análise , Sulfatos/análise , Água/análise , Oxirredução , Óxidos de Enxofre , Enxofre , Sedimentos Geológicos/análise , Poluentes Químicos da Água/análise
17.
Sci Total Environ ; 917: 170538, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38296068

RESUMO

Polyaluminum chloride (PAC) is a traditional material used for immobilizing sediment internal phosphorus (P) in field-scale experiment. Lanthanum carbonate (LC) is an emerging material which have been used in immobilizing sediment internal P in laboratory. To promote LC in practice, the premise is that it does have advantages over traditional material when used. Herein, a 90-day incubation experiment was conducted comparing the effectiveness and mechanism of LC and PAC capping in controlling sediment internal P. The results of isotherm experiment and XPS analysis indicated that the adsorption mechanism of P onto LC and PAC involved ligand exchange and formation of inner-sphere La/Al-O-P complexes. The incubation experiment revealed that PAC capping was more effective in reducing pore water soluble reactive phosphorus (SRP), exhibiting a reduction of up to 81.32 % but showed a decrease trend. However, LC capping resulted in a reduction of pore water SRP up to 52.84 % and maintained stability. On average, LC and PAC capping reduced SRP flux by 0.27 and 0.32 µg·m-2d-1, respectively relative to the control sediment. Moreover, LC capping facilitated the formation of Fe(III)/Mn(IV) oxyhydroxides, leading to an increased P adsorption, whereas PAC capping facilitated the reduction of Fe(III)/Mn(IV) minerals with P release. Additionally, LC capping resulted in the reduction of a higher ratio of mobile P/TP to stable P forms than PAC capping, as compared to the control. In contrast to PAC capping which converted mobile P to stable NaOH-rP, LC capping transformed mobile P and NaOH-rP into more stable HCl-P and ResP. Both LC and PAC capping caused variations in sediment bacterial communities. Nevertheless, PAC capping heightened the risk of Co, Ni, Cu, and Pb releases in sediment compared to LC capping. In summary, this study suggested that LC capping surpassed PAC capping in immobilizing sediment internal P.

18.
Ultrasound Med Biol ; 50(8): 1262-1272, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38777640

RESUMO

OBJECTIVE: This study aimed to develop and evaluate a deep learning-based model that could automatically measure anterior segment (AS) parameters on preoperative ultrasound biomicroscopy (UBM) images of implantable Collamer lens (ICL) surgery candidates. METHODS: A total of 1164 panoramic UBM images were preoperatively obtained from 321 patients who received ICL surgery in the Eye Center of Renmin Hospital of Wuhan University (Wuhan, China) to develop an imaging database. First, the UNet++ network was utilized to segment AS tissues automatically, such as corneal lens and iris. In addition, image processing techniques and geometric localization algorithms were developed to automatically identify the anatomical landmarks (ALs) of pupil diameter (PD), anterior chamber depth (ACD), angle-to-angle distance (ATA), and sulcus-to-sulcus distance (STS). Based on the results of the latter two processes, PD, ACD, ATA, and STS can be measured. Meanwhile, an external dataset of 294 images from Huangshi Aier Eye Hospital was employed to further assess the model's performance in other center. Lastly, a subset of 100 random images from the external test set was chosen to compare the performance of the model with senior experts. RESULTS: Whether in the internal test dataset or external test dataset, using manual labeling as the reference standard, the models achieved a mean Dice coefficient exceeding 0.880. Additionally, the intra-class correlation coefficients (ICCs) of ALs' coordinates were all greater than 0.947, and the percentage of Euclidean distance distribution of ALs within 250 µm was over 95.24%.While the ICCs for PD, ACD, ATA, and STS were greater than 0.957, furthermore, the average relative error (ARE) of PD, ACD, ATA, and STS were below 2.41%. In terms of human versus machine performance, the ICCs between the measurements performed by the model and those by senior experts were all greater than 0.931. CONCLUSION: A deep learning-based model could measure AS parameters using UBM images of ICL candidates, and exhibited a performance similar to that of a senior ophthalmologist.


Assuntos
Segmento Anterior do Olho , Aprendizado Profundo , Microscopia Acústica , Humanos , Microscopia Acústica/métodos , Segmento Anterior do Olho/diagnóstico por imagem , Masculino , Feminino , Adulto , Lentes Intraoculares Fácicas , Implante de Lente Intraocular , Adulto Jovem , Pessoa de Meia-Idade , Processamento de Imagem Assistida por Computador/métodos
19.
Int J Biol Macromol ; 242(Pt 3): 124965, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37236573

RESUMO

To improve the rapid absorption capacity of coral sand soil for rainfall, a composite of carboxymethyl cellulose-g-poly (acrylic acid-co-acrylamide)/polyvinyl alcohol sponge (CMC-g-P(AA-co-AM)/PVA) was designed and synthesized by coupling CMC-g-P(AA-co-AM) granules with a PVA sponge. The results showed that the rapid water absorption of CMC-g-P (AA-co-AM)/PVA in distilled water in 1 h was 26.45 g/g, twice that of CMC-g-P(AA-co-AM) and the PVA sponge, which is suitable for short-term rainfall. In addition, the cation had a slight influence on the water absorption capacity of CMC-g-P (AA-co-AM)/PVA, which were 29.5 and 18.9 g/g in 0.9 wt% NaCl and CaCl2 solutions, respectively, indicating the great adaptability of CMC-g-P (AA-co-AM)/PVA to high­calcium coral sand. With the addition of 2 wt% CMC-g-P (AA-co-AM)/PVA, the water interception ratio of the coral sand increased from 13.8 % to 23.7 %, and 54.6 % of the total interception water remained after 15-day evaporation. Moreover, pot experiments demonstrated that 2 wt% CMC-g-P(AA-co-AM)/PVA in coral sand enhanced plant development under water scarcity, suggesting that CMC-g-P (AA-co-AM)/PVA is a promising soil amendment for coral sand soils.


Assuntos
Acrilamida , Solo , Álcool de Polivinil , Areia , Carboximetilcelulose Sódica , Água
20.
Front Med (Lausanne) ; 10: 1164188, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37153082

RESUMO

Objective: In order to automatically and rapidly recognize the layers of corneal images using in vivo confocal microscopy (IVCM) and classify them into normal and abnormal images, a computer-aided diagnostic model was developed and tested based on deep learning to reduce physicians' workload. Methods: A total of 19,612 corneal images were retrospectively collected from 423 patients who underwent IVCM between January 2021 and August 2022 from Renmin Hospital of Wuhan University (Wuhan, China) and Zhongnan Hospital of Wuhan University (Wuhan, China). Images were then reviewed and categorized by three corneal specialists before training and testing the models, including the layer recognition model (epithelium, bowman's membrane, stroma, and endothelium) and diagnostic model, to identify the layers of corneal images and distinguish normal images from abnormal images. Totally, 580 database-independent IVCM images were used in a human-machine competition to assess the speed and accuracy of image recognition by 4 ophthalmologists and artificial intelligence (AI). To evaluate the efficacy of the model, 8 trainees were employed to recognize these 580 images both with and without model assistance, and the results of the two evaluations were analyzed to explore the effects of model assistance. Results: The accuracy of the model reached 0.914, 0.957, 0.967, and 0.950 for the recognition of 4 layers of epithelium, bowman's membrane, stroma, and endothelium in the internal test dataset, respectively, and it was 0.961, 0.932, 0.945, and 0.959 for the recognition of normal/abnormal images at each layer, respectively. In the external test dataset, the accuracy of the recognition of corneal layers was 0.960, 0.965, 0.966, and 0.964, respectively, and the accuracy of normal/abnormal image recognition was 0.983, 0.972, 0.940, and 0.982, respectively. In the human-machine competition, the model achieved an accuracy of 0.929, which was similar to that of specialists and higher than that of senior physicians, and the recognition speed was 237 times faster than that of specialists. With model assistance, the accuracy of trainees increased from 0.712 to 0.886. Conclusion: A computer-aided diagnostic model was developed for IVCM images based on deep learning, which rapidly recognized the layers of corneal images and classified them as normal and abnormal. This model can increase the efficacy of clinical diagnosis and assist physicians in training and learning for clinical purposes.

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