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1.
Exp Ther Med ; 28(5): 421, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39301252

RESUMO

Ocular metastasis (OM) in breast cancer (BC) always predicts poor prognosis. The present study explored differences in tumor markers in patients with BC with and without OM, and attempted to determine risk factors for OM in patients with BC. This study involved 629 patients with BC. Patients' clinical features were tested using χ2 test, unpaired Student's t-test and Mann-Whitney U. These parameters were analyzed using binary logistic regression to obtain risk factors for OM. A receiver operating characteristic curve was then established to determine the diagnostic value for OM. There were no significant differences in age, sex, menopausal state, and pathological type between the two groups. Significantly more axillary lymph node metastases were observed in the OM group compared with the non-ocular metastases group. Cancer antigen 153 (CA153) was revealed to be a significant independent risk factor for OM in patients with BC. The cutoff CA153 value for diagnosis of OM was 43.00 u/ml, the sensitivity was 96.15% and the specificity was 96.02%. In conclusion, CA153 was demonstrated to be a risk factor for OM in patients with BC. High levels of CA153 were associated with OM in patients with BC.

2.
Environ Res ; 263(Pt 1): 119991, 2024 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-39276831

RESUMO

In marine environments, a wide variety of microbes like bacteria, and archaea influence on the corrosion of materials. Viruses are widely distributed in biofilms among these microbes and may affect the corrosion process through interactions with key corrosive prokaryotes. However, understanding of the viral communities within biofilms and their interactions with corrosive microbes remains is limited. To improve this knowledge gap, 53 metagenomes were utilized to investigate the diversity of viruses within biofilms on 8 different materials and their interactions with corrosive microbes. Notably, the viruses within biofilms predominantly belonged to Caudoviricetes, and phylogenetic analysis of Caudoviricetes and protein-sharing networks with other environments revealed the presence of numerous novel viral clades in biofilms. The virus‒host linkages revealed a close association between viruses and corrosive microbes in biofilms. This means that viruses may modulate host corrosion-related metabolism through auxiliary metabolic genes. It was observed that the virus could enhance host resistance to metals and antibiotics via horizontal gene transfer. Interestingly, viruses could protect themselves from host antiviral systems through anti-defense systems. This study illustrates the diversity of viruses within biofilms formed on materials and the intricate interactions between viruses and corrosive microbes, showing the potential roles of viruses in corrosive biofilms.

3.
Sci Rep ; 14(1): 20514, 2024 09 03.
Artigo em Inglês | MEDLINE | ID: mdl-39227639

RESUMO

To evaluate the changes of choroidal thickness (CT) and blood flow related to myopia, and its effects of vascular endothelial growth factor (VEGFA) on choroidal vessels in myopia. Subjects were included and divided into emmetropia (EM), non-high myopia (Non-HM) and high myopia (HM) groups. we measured choroidal thickness (CT), choriocapillaris vessel density (VD), and VEGFA content in tears in humans (137 subjects for CT, VD and 84 for tear) and detected the role of VEGFA in the choroid in form-deprivation myopia (FDM) in guinea pigs. Twenty-four guinea pigs were divided into control and FDM groups, and the expression changes of choroidal vessels and VEGFA were observed and compared using immunohistochemistry and Western blotting. Twenty-one guinea pigs were divided into control, FDM + Vehicle and FDM + Conbercept groups. The changes of diopter, axis length and choroidal vessels after intravitreal injection of Conbercept were observed. There were significant differences in CT and VD among the three groups (p < 0.05). VEGFA levels in tears were significantly lower in the myopic groups, with a decreasing trend from EM to Non-HM to HM. The choroidal vascular area fraction of FDM decreased compared to the control group. FDM guinea pigs exhibited reduced choroidal vasculature and significant downregulation of VEGFA expression. Following intravitreal injection of conbercept, the FDM + Conbercept group showed greater myopia, longer axial length, and lower choroidal vascular area fraction compared to the control group. VEGFA may participate in the regulation of choroidal blood vessels and blood flow in the progression of myopia. The reduction in VEGFA may accelerates the progression of myopia.


Assuntos
Corioide , Miopia , Fator A de Crescimento do Endotélio Vascular , Corioide/metabolismo , Corioide/irrigação sanguínea , Corioide/patologia , Fator A de Crescimento do Endotélio Vascular/metabolismo , Animais , Cobaias , Miopia/metabolismo , Miopia/patologia , Masculino , Humanos , Feminino , Adulto , Biomarcadores/metabolismo , Tomografia de Coerência Óptica , Densidade Microvascular , Modelos Animais de Doenças , Proteínas Recombinantes de Fusão
4.
Ann Med Surg (Lond) ; 86(9): 5179-5190, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39239046

RESUMO

Objective: This study aims to explore the causal relationship between inflammatory markers and myopia through the use of bidirectional Mendelian randomization (MR) and myopia animal models. Methods: The authors utilized data from a comprehensive and publicly accessible genome-wide association study (GWAS) for our analysis, which includes 460 536 European ancestry control subjects and 37 362 myopia patients. Utilizing a two-sample Mendelian randomization analysis framework, 27 inflammatory markers were investigated as exposure variables with myopia serving as the outcome variable. Nine MR analysis techniques were employed, with inverse-variance weighting (IVW) as the principal MR analysis method. Heterogeneity was assessed using Cochrane's Q test. The identification of single-nucleotide polymorphisms (SNPs) and outliers linked to myopia was achieved via MR-PRESSO. The expression of interleukin-2 (IL-2) in the vitreous of guinea pigs subjected to experimentally induced form-deprivation myopia (FDM) was examined. Results: Elevated concentrations of IL-2 and IL-2ra were found to be associated [IVW estimate odds ratio (OR): 1.003, 95% CI: 1.001-1.005, P=0.001] and strongly associated (IVW estimate OR: 1.002, 95% CI: 1.000-1.003, P=0.049) with an increased risk of myopia, respectively. Conversely, lower levels of C-reactive protein (CRP) (IVW estimate OR: 0.996, 95% CI: 0.994-0.999, P=0.002) and tumour necrosis factor alpha (IVW estimate OR: 0.995, 95% CI: 0.994-0.996, P<0.001) were robustly linked to a heightened risk of myopia. IL-2 expression was notably upregulated in the vitreous of guinea pigs with experimentally induced FDM. Conclusions: Elevated levels of inflammatory factors, especially IL-2 and IL-2ra, have a potential causal relationship with myopia susceptibility, providing new insights into the pathogenesis of myopia.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38871019

RESUMO

Depression is a neurodevelopmental disorder that exhibits progressive gray matter volume (GMV) atrophy. Research indicates that brain development is influential in depression-induced GMV alterations. However, the interaction between depression and age of onset is not well understood by the underlying molecular and neuropathological mechanisms. Thus, 152 first-episode depression individuals and matched 130 healthy controls (HCs) were recruited to undergo T1-weighted high-resolution magnetic resonance imaging for this study. By two-way ANOVA, age and diagnosis were used as factors when analyzing the interaction of GMV in the participants. Then, spatial correlations between neurotransmitter maps and factor-related volume maps are established. Results illustrate a pronounced antagonistic interaction between depression and age of onset in the right insula, superior temporal gyrus, anterior cingulate gyrus, and orbitofrontal gyrus. Depression-caused reductions in GMV are mainly distributed in thalamic-limbic-cortical regions, regardless of age. For the main effect of age, adults exhibit brain atrophy in frontal, cerebellum, parietal, and temporal lobe structures. Cross-modal correlations showed that GMV changes in the interactive regions were linked with the serotonergic system and dopaminergic systems. Summarily, our results reveal the interaction between depression and age of onset in neurobiological mechanisms, which provide hints for future treatment of different ages of depression.


Assuntos
Idade de Início , Encéfalo , Substância Cinzenta , Imageamento por Ressonância Magnética , Humanos , Masculino , Feminino , Adulto , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Adulto Jovem , Pessoa de Meia-Idade , Substância Cinzenta/diagnóstico por imagem , Substância Cinzenta/patologia , Neuroimagem/métodos , Depressão/diagnóstico por imagem , Depressão/patologia , Imagem Multimodal , Adolescente , Atrofia/patologia
6.
Sci Rep ; 14(1): 11382, 2024 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762668

RESUMO

The annual increase in myopia prevalence poses a significant economic and health challenge. Our study investigated the effect of calcitriol role in myopia by inducing the condition in guinea pigs through form deprivation for four weeks. Untargeted metabolomics methods were used to analyze the differences in metabolites in the vitreous body, and the expression of vitamin D receptor (VDR) in the retina was detected. Following form deprivation, the guinea pigs received intraperitoneal injections of calcitriol at different concentrations. We assessed myopia progression using diopter measurements and biometric analysis after four weeks. Results indicated that form deprivation led to a pronounced shift towards myopia, characterized by reduced choroidal and scleral thickness, disorganized collagen fibers, and decreased scleral collagen fiber diameter. Notably, a reduction in calcitriol expression in vitreous body, diminished vitamin D and calcitriol levels in the blood, and decreased VDR protein expression in retinal tissues were observed in myopic guinea pigs. Calcitriol administration effectively slowed myopia progression, preserved choroidal and scleral thickness, and prevented the reduction of scleral collagen fiber diameter. Our findings highlight a significant decrease in calcitriol and VDR expressions in myopic guinea pigs and demonstrate that exogenous calcitriol supplementation can halt myopia development, enhancing choroidal and scleral thickness and scleral collagen fiber diameter.


Assuntos
Calcitriol , Miopia , Retina , Animais , Cobaias , Miopia/metabolismo , Miopia/tratamento farmacológico , Miopia/patologia , Calcitriol/farmacologia , Retina/metabolismo , Retina/efeitos dos fármacos , Retina/patologia , Receptores de Calcitriol/metabolismo , Receptores de Calcitriol/genética , Masculino , Modelos Animais de Doenças , Esclera/metabolismo , Esclera/efeitos dos fármacos , Esclera/patologia , Corioide/metabolismo , Corioide/efeitos dos fármacos , Corioide/patologia , Vitamina D/farmacologia , Vitamina D/administração & dosagem , Comprimento Axial do Olho , Corpo Vítreo/metabolismo , Corpo Vítreo/efeitos dos fármacos , Progressão da Doença , Colágeno/metabolismo
7.
Sci Total Environ ; 932: 173047, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38723957

RESUMO

This research was designed to estimate the contributions of phosphorus (P) in different factions from an upstream plain river network to algal growth in a downstream shallow eutrophic lake, Taihu Lake, in China. During three flow regimes, the P fractions in multiple phases (particulate, colloidal and dissolved phases) and their algal availabilities were assessed via bioassays with Dolichospermum flos-aquae as the test organism. The P partitioning patterns among multiple phases were strongly affected by the concentration of total suspended solids (TSS) that changed with the river flow regime, with stronger disturbance of sediments at lower water levels (low flow) and weaker disturbance of sediments at higher water levels (high flow) in the plain river network. The median TSS concentration across the river network decreased from 157.4 mg/L during low flow to 31.8 mg/L during high flow, and the median particulate P concentration decreased from 0.132 mg/L to 0.093 mg/L. The particulate P contributed equally to the amount of algal available P (AAP) as did the water-mobilizable P (colloidal plus dissolved phase) in the rivers flowing into Taihu Lake. The annual average concentrations of particulate algal available P (P-AAP), colloidal algal available P (C-AAP) and dissolved algal available P (D-AAP) were estimated to be 0.032 mg/L, 0.012 mg/L and 0.019 mg/L, respectively, during 2012-2018, accounting for 50.8 %, 19.0 % and 30.2 %, respectively, of the total AAP. At the watershed scale, controlling P drainage from downstream urbanized areas should be emphasized. Additionally, controlling sediment resuspension or reducing the TSS concentration in the inflowing rivers is important for decreasing the particulate P flux to downstream lakes.


Assuntos
Monitoramento Ambiental , Eutrofização , Lagos , Fósforo , Rios , Poluentes Químicos da Água , Fósforo/análise , Lagos/química , Rios/química , China , Poluentes Químicos da Água/análise , Sedimentos Geológicos/química
8.
Front Public Health ; 12: 1287911, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38566796

RESUMO

Purpose: To identify the key mental health and improvement factors in hospital administrators working from home during COVID-19 normalization prevention and control. Methods: The survey was conducted from May to June 2023, and the practical experiences of 33 hospital administrators were collected using purposive sampling. The study examined a set of mental health factor systems. The relationship structure between the factors was constructed using the Decision-making Trial and Evaluation Laboratory (DEMATEL) method. Finally, the structure was transformed using the influence weight of each factor via the DEMATEL-based Analytic Network Process. Results: Regarding influence weight, the key mental health factors of hospital administrators are mainly "lack of coordination," "time management issues," and "work-life imbalances." The influential network relation map shows that improvements can be made by addressing "improper guidelines," "laziness due to being at home," and "job insecurity" because they are the main sources of influence. The reliability level of the results for the network structure and weight was 98.79% (i.e., the gap was 1.12% < 5%). Conclusion: The network analysis model based on DEMATEL proposed in this study can evaluate the mental health factors of hospital administrators during the pandemic period from a multidimensional and multidirectional perspective and may help improve mental health problems and provide suggestions for hospital administrators.


Assuntos
Administradores Hospitalares , Saúde Mental , Humanos , Reprodutibilidade dos Testes , Projetos de Pesquisa , Inquéritos e Questionários
9.
Sci Total Environ ; 923: 171487, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38447717

RESUMO

The nitrogen (N) removal characteristics in water columns and sediments of shallow lakes, influenced by various factors, may exhibit spatial variations in lakes with algal-macrophyte dominance. The N removal rates in water columns and sediments of Lake Taihu were investigated. Our findings indicated that the total N removal rates in Lake Taihu followed the order of algae-dominance > macrophyte-dominance > pelagic lake (without the presence of algae and macrophytes). Correlation analysis revealed that the key environmental factors affecting denitrification and anammox in sediments of algae/macrophyte-type lakes were nitrate nitrogen (NO3--N), nitrite nitrogen (NO2--N), ammonia nitrogen (NH4+-N), and chlorophyll a (Chl-a). The linear regression demonstrated that a significant correlation between the denitrification and the anammox in sediments, with a correlation coefficient of 0.81 (p < 0.01). The contributions to N removal from the water columns and sediments in Lake Taihu were 53 % and 47 %, respectively. Denitrification predominantly drove N removal from sediments, whereas anammox dominated the N removal in water columns. Thus, N removal from the water columns is nonnegligible in shallow eutrophic lakes. This study enhances our understanding of N biogeochemical cycling dynamics in sediment-water and algae/macrophyte ecosystems across various shallow eutrophic lake regions.


Assuntos
Desnitrificação , Lagos , Lagos/análise , Clorofila A , Água/análise , Nitrogênio/análise , Ecossistema , Sedimentos Geológicos , China , Eutrofização
10.
ACS Omega ; 9(4): 4966-4973, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38313480

RESUMO

The slurry phase, foam phase, and slurry-foam phase interfaces are the typical locations for bubble-particle detachment, and significant advancements have been achieved in the detachment theory of the slurry phase and foam phase. However, the microscopic detachment mechanism of particles at the slurry-foam phase interface is still unclear. Specifically, there is still debate concerning the collision detachment mechanism of bubble-particle aggregates. Thus, this work investigated the effects of particle size and hydrophobicity on bubble-particle collision detachment. First, a tensiometer detected the detachment force between particles and bubbles. Next, using a high-speed dynamic camera, the collision detachment probability and detachment behavior of bubble-particle aggregates at the interface (solid surface) were statistically recorded and captured. Last, MATLAB software was used to analyze the trajectory and velocity of the particles and the velocity and projected area of the bubbles in the process of bubble-particle collision detachment. This allows for a deeper investigation of the mechanism underlying the detachment of particles of various sizes and hydrophobicity. It is discovered that as particle hydrophobicity increases, the probability of bubble-particle collision detachment reduces. This is because when particle hydrophobicity increases, so does the interaction force between particles and bubbles, improving the stability of the bubble-particle aggregates. Simultaneously, it is discovered that there are notable differences in the collision detachment mechanisms of various particle sizes. Due to their low gravity, the fine particles in the bubble-particle aggregate will slide down the bubble's surface when it collides with the solid surface. This differential velocity motion between the particle and the bubble plays a significant role in the fine particles' detachment. However, the gravity of the coarse particles is strong enough to squeeze the bubbles vertically, and bubble oscillation is an important reason for the detachment of the bubble-particle aggregates. The study's findings advance our understanding of the bubble-particle collision detachment mechanism and offer a theoretical direction for investigating collision detachment behavior at the real slurry-foam phase interface.

11.
J Environ Manage ; 354: 120263, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38387360

RESUMO

Biogenic carbon emissions, including carbon dioxide (CO2) and methane (CH4), have emerged as a major concern during organic pollutant degradation within constructed wetlands (CWs). Since these organic compounds primarily originate from the photosynthetic fixation of atmospheric CO2, it potentially introduces uncertainty when assessing the greenhouse effect of biogenic carbon emissions in CWs based on direct field observations. To objectively assessing this effect, this study proposed a new strategy by quantifying CO2-equivalent (CO2-eq) changes as carbon passes through CWs and tested it in various types of CWs based on 64 literature records. The findings reveal that CWs can contribute to CO2-eq additions, yet are only responsible for 15.6% derived from direct field observations. The type of CWs plays a crucial role in these CO2-eq additions, with vertical flow CWs causing the lowest levels (6.8%), followed by surface flow CWs (14.2%). In contrast, horizontal flow CWs are associated with the strongest CO2-eq addition (25.7%). The findings provide new insights for the objective assessment of the greenhouse effect of biogenic carbon emissions in CWs, which will be beneficial for future life cycle assessment.


Assuntos
Poluentes Ambientais , Áreas Alagadas , Efeito Estufa , Dióxido de Carbono/análise , Metano , Óxido Nitroso/análise
12.
Biochim Biophys Acta Mol Basis Dis ; 1870(3): 166981, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38101653

RESUMO

The role of extracellular matrix (ECM) remodeling in the axial elongation associated with myopia has not been fully elucidated, although it is considered a significant factor. EFEMP1, a regulator of ECM, has been associated with various pathological conditions. This study aimed to examine the involvement of EFEMP1 in scleral remodeling during form deprivation myopia. The results indicate a progressive increase in EFEMP1 expression following prolonged form deprivation treatment, followed by a subsequent decrease upon recovery. To gain a deeper understanding of the mechanism of EFEMP1, we conducted transcriptome sequencing on primary scleral fibroblasts that were subjected to lentivirus-mediated overexpression of EFEMP1. Validation was performed using lentivirus-induced overexpression and shRNA targeting EFEMP1 in combination with LY294002, a PI3K inhibitor. Our findings suggest that EFEMP1 may be involved in the development of FDM by regulating the expression of the PI3K/AKT/MMP2 axis. The AAV-mediated injection of shEFEMP1 under Tenon's capsule in guinea pigs was observed to effectively delay the progression of myopia and posterior scleral remodeling. In contrast, the AAV-mediated overexpression of EFEMP1 exacerbated the development of myopia and resulted in further thinning of collagen fibers in the posterior sclera. In summary, adjusting EFEMP1 concentrations could potentially serve as a viable approach to prevent and treat myopia by influencing the remodeling process of the posterior sclera.


Assuntos
Miopia , Esclera , Animais , Cobaias , Esclera/metabolismo , Esclera/patologia , Fosfatidilinositol 3-Quinases/metabolismo , Miopia/genética , Miopia/terapia , Miopia/metabolismo , Matriz Extracelular/metabolismo , Fibroblastos/metabolismo
13.
Environ Res ; 244: 117935, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38103781

RESUMO

Nanofiltration (NF) membranes, extensively used in advanced wastewater treatment, have broad application prospects for the removal of emerging trace organic micropollutants (MPs). The treatment performance is affected by several factors, such as the properties of NF membranes, characteristics of target MPs, and operating conditions of the NF system concerning MP rejection. However, quantitative studies on different contributors in this context are limited. To fill the knowledge gap, this study aims to assess critical impact factors controlling MP rejection and develop a feasible model for MP removal prediction. The mini-review firstly summarized membrane pore size, membrane zeta potential, and the normalized molecular size (λ = rs/rp), showeing better individual relationships with MP rejection by NF membranes. The Lindeman-Merenda-Gold model was used to quantitatively assess the relative importance of all summarized impact factors. The results showed that membrane pore size and operating pressure were the high impact factors with the highest relative contribution rates to MP rejection of 32.11% and 25.57%, respectively. Moderate impact factors included membrane zeta potential, solution pH, and molecular radius with relative contribution rates of 10.15%, 8.17%, and 7.83%, respectively. The remaining low impact factors, including MP charge, molecular weight, logKow, pKa and crossflow rate, comprised all the remaining contribution rates of 16.19% through the model calculation. Furthermore, based on the results and data availabilities from references, the machine learning-based random forest regression model was trained with a relatively low root mean squared error and mean absolute error of 12.22% and 6.92%, respectively. The developed model was then successfully applied to predict MPs' rejections by NF membranes. These findings provide valuable insights that can be applied in the future to optimize NF membrane designs, operation, and prediction in terms of removing micropollutants.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Poluentes Químicos da Água/química , Purificação da Água/métodos
14.
Pharmaceuticals (Basel) ; 16(12)2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38139842

RESUMO

The Yiqi Qubai (YQ) formula is a hospital preparation for treating vitiligo in China that has had reliable efficacy for decades. The formula consists of four herbs; however, the extraction process to produce the formula is obsolete and the active ingredients and mechanisms remain unknown. Therefore, in this paper, fingerprints were combined with the chemometrics method to screen high-quality herbs for the preparation of the YQ standard decoction (YQD). Then, the YQD preparation procedure was optimized using response surface methodology. A total of 44 chemical constituents, as well as 36 absorption components (in rat plasma) of YQD, were identified via UPLC-Q-TOF/MS. Based on the ingredients, the quality control system of YQD was optimized by establishing the SPE-UPLC-Q-TOF/MS identification method and the HPLC quantification method. Network pharmacological analysis and molecular docking showed that carasinaurone, calycosin-7-O-ß-d-glucoside, methylnissolin-3-O-glucoside, genkwanin, akebia saponin D, formononetin, akebia saponin B, and apigenin may be the key active components for treating vitiligo; the core targets associated with them were AKT1, MAPK1, and mTOR, whereas the related pathways were the PI3K-Akt, MAPK, and FoxO signaling pathways. Cellular assays showed that YQD could promote melanogenesis and tyrosinase activity, as well as the transcription and expression of tyrosinase-associated proteins (i.e., TRP-1) in B16F10 cells. In addition, YQD also increased extracellular tyrosinase activity. Further efficacy validation showed that YQD significantly promotes melanin production in zebrafish. These may be the mechanisms by which YQD improves the symptoms of vitiligo. This is the first systematic study of the YQ formula that has optimized the standard decoction preparation method and investigated the active ingredients, quality control, efficacy, and mechanisms of YQD. The results of this study lay the foundations for the clinical application and further development of the YQ formula.

15.
Materials (Basel) ; 16(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38005000

RESUMO

A Ni60+30%WC composite coating was prepared on the surface of Q235 steel by utilizing a high cooling rate, small thermal deformation of the substrate material, and the good metallurgical bonding characteristics of laser cladding technology. This paper focuses on the study of the composite coatings prepared under different process parameters in order to select the optimal process parameters and provide theoretical guidance for future practical applications. The macroscopic morphology and microstructure of t he composite coatings were investigated with the help of an optical microscope (OM) and a scanning electron microscope (SEM). The elemental distribution of the composite coatings was examined using an X-ray diffractometer. The microhardness and wear resistance of the composite coatings were tested using a microhardness tester, a friction tester, and a three-dimensional (3D) profilometer. The results of all the samples showed that the Ni60+30%WC composite coatings prepared at a laser power of 1600 W and a scanning speed of 10 mm/s were well formed, with a dense microstructure, and the microhardness is more than four times higher than the base material, the wear amount is less than 50% of the base material, and the wear resistance has been significantly improved. Therefore, the experimental results for the laser power of 1600 W and scanning speed of 10 mm/s are the optimal process parameters for the preparation of Ni60+30%WC.

16.
Front Plant Sci ; 14: 1276289, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37941677

RESUMO

Phytoplankton are key members of river ecosystems wherein they influence and regulate the health of the local environment. Headwater streams are subject to minimal human activity and serve as the sources of rivers, generally exhibiting minimal pollution and strong hydrodynamic forces. To date, the characteristics of phytoplankton communities in headwater streams have remained poorly understood. This study aims to address this knowledge gap by comparing phytoplankton communities in headwater streams with those in plain rivers. The results demonstrated that within similar watershed sizes, lower levels of spatiotemporal variability were observed with respect to phytoplankton community as compared to plain rivers. Lower nutrient levels and strong hydrodynamics contribute to phytoplankton growth limitation in these streams, thereby reducing the levels of spatiotemporal variation. However, these conditions additionally contribute to greater phytoplankton diversity and consequent succession towards Cyanophyta. Overall, these results provide new insights into the dynamics of headwater stream ecosystems and support efforts for their ecological conservation.

17.
Biosci Rep ; 43(10)2023 10 31.
Artigo em Inglês | MEDLINE | ID: mdl-37665319

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) is a chronic, systemic autoimmune disorder that primarily causes symmetrical polyarthritis and bone deformity. In RA patients, sight-threatening inflammatory eye complications would be expected. OBJECTIVE: The objective of the study is to ascertain the macular retinal vessel density changes in RA patients and controls using optical coherence tomography angiography (OCTA), and to investigate the association between disease and microvascular density alterations. METHODS: A total of 12 RA patients (24 eyes) and 12 age- and gender-matched control participants (24 eyes) were recruited to the study. We used the Early Treatment Diabetic Retinopathy Study partitioning, hemispheric quadrants and annular partitioning to segment each image into different subregions. The vascular density of superficial retina layer, deep retina layer and conjunctival capillary plexus was quantitatively measured by OCTA and compared with the control group. Correlation analysis was used to explore the relationship between STMI and conjunctival capillaries densities. RESULTS: In the superficial retinal layer, the vascular density of S, I, L, SL, SR, IL and C1-C5 were significantly decreased in the RA group compared with the control group (P<0.05). For the deep retinal layer, the vascular density of S, SL, SR, IL, C1, C2 and C4 also decreased in RA group. A significant positive correlation was indicated between conjunctival vascular and STMI densities (r = 0.713, P<0.05). CONCLUSION: OCTA results suggest that RA patients present with a reduced macular retinal vascular density. These subtle alterations of ocular microcirculation may precede severe eye involvements and may be a potential biomarker for early distinguishing abnormal eyes from healthy eyes.


Assuntos
Artrite Reumatoide , Tomografia de Coerência Óptica , Humanos , Feminino , Angiofluoresceinografia/métodos , Tomografia de Coerência Óptica/métodos , Retina/diagnóstico por imagem , Microvasos/diagnóstico por imagem , Artrite Reumatoide/diagnóstico por imagem
18.
Sensors (Basel) ; 23(15)2023 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-37571567

RESUMO

Respiratory rate and skin humidity are important physiological signals and have become an important basis for disease diagnosis, and they can be monitored by humidity sensors. However, it is difficult to employ high-quality humidity sensors on a broad scale due to their high cost and complex fabrication. Here, we propose a reliable, convenient, and efficient method to mass-produce humidity sensors. A capacitive humidity sensor is obtained by ablating a polyimide (PI) film with a picosecond laser to produce an interdigital electrode (IDE), followed by drop-casting graphene oxide (GO) as a moisture-sensitive material on the electrode. The sensor has long-time stability, a wide relative humidity (RH) detection range from 10% to 90%, and high sensitivity (3862 pF/%RH). In comparison to previous methods, the technology avoids the complex procedures and expensive costs of conventional interdigital electrode preparation. Furthermore, we discuss the effects of the electrode gap size and the amount of graphene oxide on humidity sensor performance, analyze the humidity sensing mechanism by impedance spectrum, and finally perform the monitoring of human respiratory rate and skin humidity change in a non-contact manner.


Assuntos
Grafite , Humanos , Umidade , Eletrodos , Lasers , Taxa Respiratória
19.
New Phytol ; 239(5): 1790-1803, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37430391

RESUMO

Meiotic crossovers ensure accurate chromosome segregation and increase genetic diversity. RAD51C and RAD51D play an early role in facilitating RAD51 during homologous recombination. However, their later function in meiosis is largely unknown in plants. Here, through targeted disruption of RAD51C and RAD51D, we generated three new mutants and revealed their later meiotic role in crossover maturation. The rad51c-3 and rad51d-4 mutants showed a mixture of bivalents and univalents and no chromosomal entanglements, whereas rad51d-5 exhibited an intermediate phenotype with reduced chromosomal entanglements and increased bivalent formation compared with knockout alleles. Comparisons of RAD51 loadings and chromosomal entanglements in these single mutants, rad51c-3 rad51d-4, rad51c-3 dmc1a dmc1b, and rad51d-4 dmc1a dmc1b suggest that the retained level of RAD51 in mutants is required for uncovering their function in crossover formation. Reductions in chiasma frequency and later HEI10 foci in these mutants support that crossover maturation requires RAD51C and RAD51D. Moreover, interaction between RAD51D and MSH5 indicates that RAD51 paralogs may cooperate with MSH5 to ensure accurate Holliday junction processing into crossover products. This finding of the role of RAD51 paralogs in crossover control may be conserved from mammals to plants and advances our current understanding of these proteins.


Assuntos
Oryza , Animais , Oryza/genética , Oryza/metabolismo , Rad51 Recombinase/genética , Rad51 Recombinase/metabolismo , Meiose/genética , Recombinação Homóloga , Mamíferos
20.
J Biophotonics ; 16(11): e202300133, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37369631

RESUMO

OBJECTIVE: To evaluate the effect of hydroxychloroquine on conjunctival and retinal microvascular density in rheumatoid arthritis (RA) patients. METHODS: Ten healthy controls, 10 RA patients who had not been treated with hydroxychloroquine, and 10 RA patients who had been treated with chloroquine for more than 5 years were recruited. Optical coherence tomography (OCTA) was used to examine the conjunctival and superficial and deep retinal microvascular density and compared the differences in microvascular density between the three groups. RESULTS: The vascular density in RA group in superficial microvascular was significantly lower than that in control group (p < 0.001). Compared with RA group, the chloroquine group showed statistically significantly lower microvascular (p < 0.001) and deep microvascular (p = 0.018). Superficial microvascular was positively correlated with conjunctival vessel density in RA patients (r = 0.868, p = 0.0048). CONCLUSIONS: The use of chloroquine could further reduce the vascular density in the absence of statistical difference in the course of the disease.


Assuntos
Artrite Reumatoide , Hidroxicloroquina , Humanos , Hidroxicloroquina/uso terapêutico , Hidroxicloroquina/farmacologia , Vasos Retinianos/diagnóstico por imagem , Cloroquina/uso terapêutico , Cloroquina/farmacologia , Angiofluoresceinografia/métodos , Artrite Reumatoide/diagnóstico por imagem , Artrite Reumatoide/tratamento farmacológico , Tomografia de Coerência Óptica/métodos
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