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1.
J Phys Chem A ; 128(37): 7889-7898, 2024 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-39230386

RESUMO

The composite material, consisting of graphene oxide (GO) and chromium metal-organic frameworks (Cr-MOFs), was successfully synthesized by using a solvothermal method. The organic ligand employed was 2,5-dihydroxyterephthalic acid, while chromium acetate served as the source of the metal. The resulting material underwent characterization through Fourier transform infrared, scanning electron microscopy, and X-ray diffraction techniques. Subsequently, the adsorption capacity of the composite material toward moxifloxacin was evaluated. The results indicated a gradual increase in the moxifloxacin removal rate from GO/Cr-MOFs over time until reaching an equilibrium with a maximum removal rate of 90.4%. Additionally, it was observed that higher temperatures led to a decrease in the adsorption capacity. By incorporating 30 mg of GO/Cr-MOFs into a solution containing 40 ppm of moxifloxacin, the adsorption capacity could be maximized at 222.25 mg/g. Experimental data on MOF adsorption of moxifloxacin were analyzed using pseudo-first-order kinetics (PFO), pseudo-second-order kinetics (PSO), and Langmuir, Freundlich, and Temkin isotherm models for theoretical research purposes. Results showed that the PSO model exhibited a better correlation than the PFO model did. Furthermore, experimental data demonstrated good agreement with the Freundlich isothermal model, suggesting its effectiveness in accurately describing the adsorption process. Henceforth, it can be concluded that chemisorption plays a significant role in removing moxifloxacin by GO/Cr-MOFs. The van't Hoff equation analysis revealed an exothermic and spontaneous nature of moxifloxacin adsorption onto GO/Cr-MOFs. Compared to other materials, the GO/Cr-MOF composite exhibited high potential for applications such as drug removal or related fields.

2.
BMC Med Imaging ; 24(1): 204, 2024 Aug 06.
Artigo em Inglês | MEDLINE | ID: mdl-39107679

RESUMO

BACKGROUND: Computed tomography (CT) is widely in clinics and is affected by metal implants. Metal segmentation is crucial for metal artifact correction, and the common threshold method often fails to accurately segment metals. PURPOSE: This study aims to segment metal implants in CT images using a diffusion model and further validate it with clinical artifact images and phantom images of known size. METHODS: A retrospective study was conducted on 100 patients who received radiation therapy without metal artifacts, and simulated artifact data were generated using publicly available mask data. The study utilized 11,280 slices for training and verification, and 2,820 slices for testing. Metal mask segmentation was performed using DiffSeg, a diffusion model incorporating conditional dynamic coding and a global frequency parser (GFParser). Conditional dynamic coding fuses the current segmentation mask and prior images at multiple scales, while GFParser helps eliminate high-frequency noise in the mask. Clinical artifact images and phantom images are also used for model validation. RESULTS: Compared with the ground truth, the accuracy of DiffSeg for metal segmentation of simulated data was 97.89% and that of DSC was 95.45%. The mask shape obtained by threshold segmentation covered the ground truth and DSCs were 82.92% and 84.19% for threshold segmentation based on 2500 HU and 3000 HU. Evaluation metrics and visualization results show that DiffSeg performs better than other classical deep learning networks, especially for clinical CT, artifact data, and phantom data. CONCLUSION: DiffSeg efficiently and robustly segments metal masks in artifact data with conditional dynamic coding and GFParser. Future work will involve embedding the metal segmentation model in metal artifact reduction to improve the reduction effect.


Assuntos
Artefatos , Metais , Imagens de Fantasmas , Próteses e Implantes , Tomografia Computadorizada por Raios X , Humanos , Tomografia Computadorizada por Raios X/métodos , Estudos Retrospectivos , Algoritmos
3.
Int J Mol Sci ; 25(11)2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38892008

RESUMO

The NAC family of transcription factors includes no apical meristem (NAM), Arabidopsis thaliana transcription activator 1/2 (ATAF1/2), and cup-shaped cotyledon (CUC2) proteins, which are unique to plants, contributing significantly to their adaptation to environmental challenges. In the present study, we observed that the PvNAC52 protein is predominantly expressed in the cell membrane, cytoplasm, and nucleus. Overexpression of PvNAC52 in Arabidopsis strengthened plant resilience to salt, alkali, osmotic, and ABA stresses. PvNAC52 significantly (p < 0.05) reduced the degree of oxidative damage to cell membranes, proline content, and plant water loss by increasing the expression of MSD1, FSD1, CSD1, POD, PRX69, CAT, and P5CS2. Moreover, the expression of genes associated with abiotic stress responses, such as SOS1, P5S1, RD29A, NCED3, ABIs, LEAs, and DREBs, was enhanced by PvNAC52 overexpression. A yeast one-hybrid assay showed that PvNAC52 specifically binds to the cis-acting elements ABRE (abscisic acid-responsive elements, ACGTG) within the promoter. This further suggests that PvNAC52 is responsible for the transcriptional modulation of abiotic stress response genes by identifying the core sequence, ACGTG. These findings provide a theoretical foundation for the further analysis of the targeted cis-acting elements and genes downstream of PvNAC52 in the common bean.


Assuntos
Ácido Abscísico , Regulação da Expressão Gênica de Plantas , Phaseolus , Proteínas de Plantas , Fatores de Transcrição , Ácido Abscísico/metabolismo , Ácido Abscísico/farmacologia , Álcalis , Arabidopsis/genética , Arabidopsis/metabolismo , Pressão Osmótica , Phaseolus/genética , Phaseolus/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Regiões Promotoras Genéticas , Estresse Fisiológico/genética , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Regulação para Cima
4.
Molecules ; 29(16)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39202951

RESUMO

In this study, Co/Cd-MOFs were synthesized via a solvothermal method. The resulting material was subjected to calcination at 900 °C for 2 h and characterized using FT-IR, XRD, and SEM techniques to assess its efficacy in moxifloxacin removal. The experimental findings revealed that the maximum adsorption capacity of Co/Cd-MOFs for moxifloxacin was observed at 350.4 mg/g within a 5 h timeframe. Furthermore, the analysis based on the pseudo-second-order kinetic model demonstrated that the adsorption process adhered to this specific model. Additionally, the adsorption isotherm analysis indicated that Freundlich multilayer adsorption provided the best description of the interaction between moxifloxacin and the Co/Cd-MOF material. These experimental and theoretical results collectively suggest that employing Co/Cd-MOFs as adsorbents holds promise for wastewater treatment applications.

5.
Ren Fail ; 45(1): 2217276, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37246750

RESUMO

OBJECTIVE: The brain neuromechanism in maintenance hemodialysis patients (MHD) with cognitive impairment (CI) remains unclear. The study aimed to probe the relationship between spontaneous brain activity and CI by using resting-state functional magnetic resonance imaging (rs-fMRI) data. METHODS: Here, 55 MHD patients with CI and 28 healthy controls were recruited. For baseline data, qualitative data were compared between groups using the χ2 test; quantitative data were compared between groups using the independent samples t-test, ANOVA test, Mann-Whitney U-test, or Kruskal-Wallis test. Comparisons of ALFF/fALFF/ReHo values among the three groups were calculated by using the DPABI toolbox, and then analyzing the correlation with clinical variables. p < .05 was considered a statistically significant difference. Furthermore, back propagation neural network (BPNN) was utilized to predict cognitive function. RESULTS: Compared with the MHD-NCI group, the patients with MHD-CI had more severe anemia and higher urea nitrogen levels, lower mALFF values in the left postcentral gyrus, lower mfALFF values in the left inferior temporal gyrus, and greater mALFF values in the right caudate nucleus (p < .05). The above-altered indicators were correlated with MOCA scores. BPNN prediction models indicated that the diagnostic efficacy of the model which inputs were hemoglobin, urea nitrogen, and mALFF value in the left central posterior gyrus was optimal (R2 = 0.8054), validation cohort (R2 = 0.7328). CONCLUSION: The rs-fMRI can reveal the neurophysiological mechanism of cognitive impairment in MHD patients. In addition, it can serve as a neuroimaging marker for diagnosing and evaluating cognitive impairment in MHD patients.


Assuntos
Mapeamento Encefálico , Disfunção Cognitiva , Humanos , Imageamento por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Cognição , Disfunção Cognitiva/diagnóstico por imagem , Disfunção Cognitiva/etiologia , Diálise Renal/efeitos adversos , Ureia
6.
Biosci Biotechnol Biochem ; 86(9): 1220-1230, 2022 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-35723236

RESUMO

Sterol regulatory element-binding proteins (SREBPs) are transcription factors that have important roles in the genes involved in lipid biosynthesis. In this study, it was found that the flavonoid pectolinarigenin, reduced the activity of SRE-containing fatty acid synthase (FAS) promoter and the mRNA expressions of SREBP target genes in human hepatoma (Huh-7) cells. Moreover, compared with other flavonoids, pectolinarigenin reduced the mature forms of SREBPs in a dose-dependent manner. The insulin-induced gene (INSIG) and proteasome were not involved in the pectolinarigenin-mediated reduction of mature forms of SREBPs. Pectolinarigenin also reduced the lipid contents in vitro. These results suggest that pectolinarigenin may inhibit lipogenesis through suppressing SREBP activity, at least partially, via the formation of SREBPs mature forms, thereby reducing the expression of their downstream genes related to lipogenesis. To the best of our knowledge, this is the first work that shows how pectolinarigenin affects cellular lipid levels by affecting SREBPs.


Assuntos
Flavonoides , Proteínas de Ligação a Elemento Regulador de Esterol , Proteínas Estimuladoras de Ligação a CCAAT , Cromonas , Flavonoides/farmacologia , Humanos , Lipídeos , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Proteína de Ligação a Elemento Regulador de Esterol 2 , Proteínas de Ligação a Elemento Regulador de Esterol/metabolismo , Esteróis
7.
Water Sci Technol ; 86(9): 2106-2123, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36378169

RESUMO

Red mud of low cost is regarded as a promising alternative to heterogeneous catalysts for activating peroxymonosulfate (PMS) to degrade m-cresol. Improper valence states of metal oxides and coated active substances in red mud greatly hampered its wide application. To solve this problem, the modified red mud (WRMG/700) was prepared by the pyrolysis reduction of glucose in N2 atmosphere. X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectrum (XPS) analysis confirmed the production of Fe3O4, MnO and NiO in red mud and their gathering on the surface of particles. WRMG/700 exhibited the excellent performance toward PMS activation for the m-cresol degradation with 99.02% degradation efficiency and a pH-independent catalytic activity between initial pH 3-8. The removal efficiency of COD increased with the reaction time under the optimized degradation conditions. The free radical scavenging experiments and electron paramagnetic resonance (EPR) test confirmed 1O2 played a dominant role during m-cresol degradation in the WRMG/700/PMS system, implying m-cresol degradation was a non-radical oxidation process. Accordingly, the possible reaction mechanism was proposed. WRMG/700 retained its activation performance even after five recycles. This study showed a low cost and simple operation process for m-cresol elimination.


Assuntos
Glucose , Pirólise , Peróxidos/química
8.
Plant J ; 104(1): 252-267, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32662159

RESUMO

Rhamnogalacturonan-II (RG-II) is structurally the most complex glycan in higher plants, containing 13 different sugars and 21 distinct glycosidic linkages. Two monomeric RG-II molecules can form an RG-II-borate diester dimer through the two apiosyl (Api) residues of side chain A to regulate cross-linking of pectin in the cell wall. But the relationship of Api biosynthesis and RG-II dimer is still unclear. In this study we investigated the two homologous UDP-D-apiose/UDP-D-xylose synthases (AXSs) in Arabidopsis thaliana that synthesize UDP-D-apiose (UDP-Api). Both AXSs are ubiquitously expressed, while AXS2 has higher overall expression than AXS1 in the tissues analyzed. The homozygous axs double mutant is lethal, while heterozygous axs1/+ axs2 and axs1 axs2/+ mutants display intermediate phenotypes. The axs1/+ axs2 mutant plants are unable to set seed and die. By contrast, the axs1 axs2/+ mutant plants exhibit loss of shoot and root apical dominance. UDP-Api content in axs1 axs2/+ mutants is decreased by 83%. The cell wall of axs1 axs2/+ mutant plants is thicker and contains less RG-II-borate complex than wild-type Col-0 plants. Taken together, these results provide direct evidence of the importance of AXSs for UDP-Api and RG-II-borate complex formation in plant growth and development.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/crescimento & desenvolvimento , Pectinas/metabolismo , Açúcares de Uridina Difosfato/metabolismo , Arabidopsis/metabolismo , Proteínas de Arabidopsis/fisiologia , Pólen/metabolismo
9.
Angew Chem Int Ed Engl ; 60(17): 9553-9561, 2021 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-33569863

RESUMO

Photocaging holds promise for the precise manipulation of biological events in space and time. However, current near-infrared (NIR) photocages are oxygen-dependent for their photolysis and lack of timely feedback regulation, which has proven to be the major bottleneck for targeted therapy. Herein, we present a hypoxia-dependent photo-activation mechanism of dialkylamine-substituted cyanine (Cy-NH) accompanied by emissive fragments generation, which was validated with retrosynthesis and spectral analysis. For the first time, we have realized the orthogonal manipulation of this hypoxia-dependent photocaging and dual-modal optical signals in living cells and tumor-bearing mice, making a breakthrough in the direct spatiotemporal control and in vivo feedback regulation. This unique photoactivation mechanism overcomes the limitation of hypoxia, which allows site-specific remote control for targeted therapy, and expands the photo-trigger toolbox for on-demand drug release, especially in a physiological context with dual-mode optical imaging under hypoxia.


Assuntos
Carbocianinas/química , Hipóxia , Neoplasias Experimentais/diagnóstico por imagem , Técnicas Fotoacústicas , Células A549 , Animais , Liberação Controlada de Fármacos , Células Hep G2 , Humanos , Raios Infravermelhos , Camundongos , Estrutura Molecular , Imagem Óptica , Fotólise
10.
Small ; 16(5): e1905641, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31898866

RESUMO

Photodynamic therapy (PDT) is a promising technique for cancer therapy, providing good therapeutic efficacy with minimized side effect. However, the lack of oxygen supply in the hypoxic tumor site obviously restricts the generation of singlet oxygen (1 O2 ), thus limiting the efficacy of PDT. So far, the strategies to improve PDT efficacy usually rely on complicated nanosystems, which require sophisticated design or complex synthetic procedure. Herein, iodine-rich semiconducting polymer nanoparticles (SPN-I) for enhanced PDT, using iodine-induced intermolecular heavy-atom effect to elevate the 1 O2 generation, are designed and prepared. The nanoparticles are composed of a near-infrared (NIR) absorbing semiconducting polymer (PCPDTBT) serving as the photosensitizer and source of fluorescence signal, and an iodine-grafted amphiphilic diblock copolymer (PEG-PHEMA-I) serving as the 1 O2 generation enhancer and nanocarrier. Compared with SPN composed of PEG-b-PPG-b-PEG and PCPDTBT (SPN-P), SPN-I can enhance the 1 O2 generation by 1.5-fold. In addition, SPN-I have high X-ray attenuation coefficient because of the high density of iodine in PEG-PHEMA-I, providing SPN-I the ability of use with computed tomography (CT) and fluorescence dual-modal imaging. The study thus provides a simple nanotheranostic platform composed of two components for efficient CT/fluorescence dual-modal imaging-guided enhanced PDT.


Assuntos
Iodo , Neoplasias , Fotoquimioterapia , Polímeros , Pontos Quânticos , Humanos , Iodo/química , Neoplasias/terapia , Fotoquimioterapia/métodos , Fármacos Fotossensibilizantes/química , Fármacos Fotossensibilizantes/uso terapêutico , Polímeros/química , Polímeros/uso terapêutico , Pontos Quânticos/química , Pontos Quânticos/uso terapêutico , Tomografia Computadorizada por Raios X
11.
Ecotoxicol Environ Saf ; 194: 110384, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32126412

RESUMO

Electrolytic manganese residue (EMR) contains a large amount of NH4+-N and Mn2+ and can negatively impact the environment. A stabilization treatment of soluble contaminants in the EMR is necessary for its reuse and safe stacking. This study presents experimental results for the stabilization of NH4+-N and Mn2+ in the EMR using phosphogypsum leachate as a low-cost phosphate source and MgO/CaO (PLMC) process. The results demonstrated that the stabilization efficiency of NH4+-N and Mn2+ was 93.65% and 99.99%, respectively, under the following conditions: a phosphogypsum leachate dose of 1.5 mL g-1, an added MgO dose of 0.036 g g-1, an added CaO dose of 0.1 g g-1 and a reaction time of 2 h. The stabilization effect of the PLMC process was higher and more cost effective than that of using Na3PO4·12H2O and MgO/CaO. The concentration of NH4+-N and Mn2+ in the leaching liquor decreased to 80 mg L-1 and 0.5 mg L-1, respectively, after the stabilization under the optimum conditions. The stabilization characteristics indicated that NH4+-N was stabilized to form NH4MgPO4·6H2O (struvite) and that Mn2+ was stabilized to form Mn5(PO4)2(OH)4, Mn3(PO4)2·3H2O and Mn(OH)2. PO43--P, F-, and heavy metal ions of the phosphogypsum leachate were removed from the leaching liquor and stabilized in the treated EMR.


Assuntos
Compostos de Cálcio/química , Sulfato de Cálcio/química , Óxido de Magnésio/química , Manganês/análise , Óxidos/química , Fósforo/química , Amônia/análise , Amônia/química , Eletrólise , Eletrólitos , Poluentes Ambientais/análise , Poluentes Ambientais/química , Resíduos Industriais/análise , Manganês/química , Solubilidade , Estruvita/análise , Estruvita/química
12.
Ecotoxicol Environ Saf ; 192: 110316, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32061981

RESUMO

Mercury (Hg) re-emission from sediment is an important process in the biogeochemistry cycles of Hg in the aquatic ecosystem. The contribution of Hg released from sediment to water remains unclear for some shallow lakes. Lake Nansi is a typical shallow lake in northern China that is divided into upper and lower lakes by a dam. The Hg species in the water profile and sediment were measured from two sampling sites in the lake. Nansi Lake was not markedly contaminated by Hg. The Hg profile in the sediment indicated that the demand for energy and the policy management in the catchment influenced the Hg accumulation in its sediment. On the basis of Fick's first law and the sedimentation rate, the diffusion flux of dissolved Hg from sediment to overlying water and the accumulation flux were estimated. According to one-year scale estimation, approximately 10%-13% the Hg in the sediments can be re-released into the overlying water. The Hg diffused from the sediment accounted for 7.9%-16% of the Hg in the overlying water. These results of this study improve the understanding of the sources of pollution in water and enable researchers to focus on the contribution of sediment to the pollution of water in shallow lakes.


Assuntos
Sedimentos Geológicos/química , Lagos/química , Mercúrio/análise , Poluentes Químicos da Água/análise , China , Monitoramento Ambiental
13.
Angew Chem Int Ed Engl ; 59(23): 9059-9066, 2020 06 02.
Artigo em Inglês | MEDLINE | ID: mdl-31984609

RESUMO

Chemiluminescence (CL)-based technologies have revolutionized in vivo monitoring of biomolecules. However, significant technical hurdles have limited the achievement of trigger-controlled, bright, and enriched CL signal. Herein, a dual-lock strategy uses sequence-dependent triggers for bright optical imaging with real-time fluorescent signal and ultra-sensitive CL signal. These probes can obtain an analyte-triggered accumulation of stable pre-chemiluminophore with aggregation-induced emission (AIE), and then the pre-chemiluminophore exhibits a rapid photooxidation process (1,2-dioxetane generation) by TICT-based free-radical addition, thereby achieving an enrichment and bright CL signal. The dual-lock strategy expands the in vivo toolbox for highly accurate analysis and has for the first time allowed access to accurately sense and trace biomolecules with high-resolution, dual-mode of chemo-fluoro-luminescence, and three-dimensional (3D) imaging in living animals.


Assuntos
Substâncias Luminescentes/química , Imagem Óptica/métodos , Animais , Linhagem Celular Tumoral , Transformação Celular Neoplásica , Imageamento Tridimensional , Cinética , Camundongos , Oxirredução , Processos Fotoquímicos , Fatores de Tempo
14.
Plant Cell Environ ; 42(3): 1033-1044, 2019 03.
Artigo em Inglês | MEDLINE | ID: mdl-30378140

RESUMO

CLE peptides have been implicated in various developmental processes of plants and mediate their responses to environmental stimuli. However, the biological relevance of most CLE genes remains to be functionally characterized. Here, we report that CLE9, which is expressed in stomata, acts as an essential regulator in the induction of stomatal closure. Exogenous application of CLE9 peptides or overexpression of CLE9 effectively led to stomatal closure and enhanced drought tolerance, whereas CLE9 loss-of-function mutants were sensitivity to drought stress. CLE9-induced stomatal closure was impaired in abscisic acid (ABA)-deficient mutants, indicating that ABA is required for CLE9-medaited guard cell signalling. We further deciphered that two guard cell ABA-signalling components, OST1 and SLAC1, were responsible for CLE9-induced stomatal closure. MPK3 and MPK6 were activated by the CLE9 peptide, and CLE9 peptides failed to close stomata in mpk3 and mpk6 mutants. In addition, CLE9 peptides stimulated the induction of hydrogen peroxide (H2 O2 ) and nitric oxide (NO) synthesis associated with stomatal closure, which was abolished in the NADPH oxidase-deficient mutants or nitric reductase mutants, respectively. Collectively, our results reveal a novel ABA-dependent function of CLE9 in the regulation of stomatal apertures, thereby suggesting a potential role of CLE9 in the stress acclimatization of plants.


Assuntos
Ácido Abscísico/metabolismo , Proteínas de Arabidopsis/fisiologia , Arabidopsis/fisiologia , Peróxido de Hidrogênio/metabolismo , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Óxido Nítrico/metabolismo , Estômatos de Plantas/fisiologia , Adaptação Fisiológica , Arabidopsis/metabolismo , Desidratação , Óxido Nítrico/fisiologia
15.
New Phytol ; 217(1): 290-304, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28940201

RESUMO

Accumulating data indicate that strigolactones (SLs) are implicated in the response to environmental stress, implying a potential effect of SLs on stomatal response and thus stress acclimatization. In this study, we investigated the molecular mechanism underlying the effect of SLs on stomatal response and their interrelation with abscisic acid (ABA) signaling. The impact of SLs on the stomatal response was investigated by conducting SL-feeding experiments and by analyzing SL-related mutants. The involvement of endogenous ABA and ABA-signaling components in SL-mediated stomatal closure was physiologically evaluated using genetic mutants. Pharmacological and genetic approaches were employed to examine hydrogen peroxide (H2 O2 ) and nitric oxide (NO) production. SL-related mutants exhibited larger stomatal apertures, while exogenous SLs were able to induce stomatal closure and rescue the more widely opening stomata of SL-deficient mutants. The SL-biosynthetic genes were induced by abiotic stress in shoot tissues. Disruption of ABA-biosynthetic genes, as well as genes that function in guard cell ABA signaling, resulted in no impairment in SL-mediated stomatal response. However, disruption of MORE AXILLARY GROWTH2 (MAX2), DWARF14 (D14), and the anion channel gene SLOW ANION CHANNEL-ASSOCIATED 1 (SLAC1) impaired SL-triggered stomatal closure. SLs stimulated a marked increase in H2 O2 and NO contents, which is required for stomatal closure. Our results suggest that SLs play a prominent role, together with H2 O2 /NO production and SLAC1 activation, in inducing stomatal closure in an ABA-independent mechanism.


Assuntos
Proteínas de Arabidopsis/metabolismo , Arabidopsis/fisiologia , Peróxido de Hidrogênio/metabolismo , Lactonas/farmacologia , Proteínas de Membrana/metabolismo , Óxido Nítrico/metabolismo , Ácido Abscísico/metabolismo , Arabidopsis/genética , Proteínas de Arabidopsis/genética , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Proteínas de Membrana/genética , Reguladores de Crescimento de Plantas/metabolismo , Estômatos de Plantas/genética , Estômatos de Plantas/fisiologia , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo
16.
J Cardiovasc Pharmacol ; 63(1): 76-82, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24072176

RESUMO

Vascular calcification is a common comorbidity in elderly patients with diabetes mellitus or renal insufficiency. A large number of studies have shown that vascular calcification can be induced and accelerated in patients undergoing long-term treatment with warfarin, leading to some severe complications, such as hypertension, atherosclerosis, valvular calcification, and coronary calcification, especially in the population with atrial fibrillation, hemodialysis, and chronic kidney disease. Warfarin inhibits the activation of vitamin K-dependent coagulation factors and affects the function of vitamin K-dependent proteins via interference of the vitamin K cycle by antagonizing vitamin K. One of its consequences is adverse effects on the expression and function of matrix Gla protein, one of the important vitamin K-dependent proteins. Matrix Gla protein acts as an inhibitor of vascular calcification by blocking bone morphogenetic protein signaling or promoting the phagocytosis of apoptotic bodies; moreover, it restrains the formation of calcification directly resulting in the promotion of vascular calcification. This article also discusses the various treatments for vascular calcification caused by warfarin.


Assuntos
Anticoagulantes/efeitos adversos , Calcificação Vascular/induzido quimicamente , Varfarina/efeitos adversos , Biomarcadores/sangue , Humanos , Calcificação Vascular/diagnóstico , Calcificação Vascular/terapia
17.
Math Biosci Eng ; 21(3): 3838-3859, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38549310

RESUMO

Brain functional networks derived from functional magnetic resonance imaging (fMRI) provide a promising approach to understanding cognitive processes and predicting cognitive abilities. The topological attribute parameters of global networks are taken as the features from the overall perspective. It is constrained to comprehend the subtleties and variances of brain functional networks, which fell short of thoroughly examining the complex relationships and information transfer mechanisms among various regions. To address this issue, we proposed a framework to predict the cognitive function status in the patients with end-stage renal disease (ESRD) at a functional subnetwork scale (CFSFSS). The nodes from different network indicators were combined to form the functional subnetworks. The area under the curve (AUC) of the topological attribute parameters of functional subnetworks were extracted as features, which were selected by the minimal Redundancy Maximum Relevance (mRMR). The parameter combination with improved fitness was searched by the enhanced whale optimization algorithm (E-WOA), so as to optimize the parameters of support vector regression (SVR) and solve the global optimization problem of the predictive model. Experimental results indicated that CFSFSS achieved superior predictive performance compared to other methods, by which the mean absolute error (MAE), mean absolute percentage error (MAPE), and root mean square error (RMSE) were up to 0.5951, 0.0281 and 0.9994, respectively. The functional subnetwork effectively identified the active brain regions associated with the cognitive function status, which offered more precise features. It not only helps to more accurately predict the cognitive function status, but also provides more references for clinical decision-making and intervention of cognitive impairment in ESRD patients.


Assuntos
Cognição , Falência Renal Crônica , Animais , Humanos , Encéfalo/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Algoritmos , Baleias , Falência Renal Crônica/diagnóstico por imagem
18.
Biomed Mater Eng ; 35(2): 99-124, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38217572

RESUMO

BACKGROUND: Intervertebral cages used in clinical applications were often general products with standard specifications, which were challenging to match with the cervical vertebra and prone to cause stress shielding and subsidence. OBJECTIVE: To design and fabricate customized tantalum (Ta) intervertebral fusion cages that meets the biomechanical requirements of the cervical segment. METHODS: The lattice intervertebral cages were customized designed and fabricated by the selective laser melting. The joint and muscle forces of the cervical segment under different movements were analyzed using reverse dynamics method. The stress characteristics of cage, plate, screws and vertebral endplate were analyzed by finite element analysis. The fluid flow behaviors and permeability of three lattice structures were simulated by computational fluid dynamics. Compression tests were executed to investigate the biomechanical properties of the cages. RESULTS: Compared with the solid cages, the lattice-filled structures significantly reduced the stress of cages and anterior fixation system. In comparison to the octahedroid and quaddiametral lattice-filled cages, the bitriangle lattice-filled cage had a lower stress shielding rate, higher permeability, and superior subsidence resistance ability. CONCLUSION: The inverse dynamics simulation combined with finite element analysis is an effective method to investigate the biomechanical properties of the cervical vertebra during movements.


Assuntos
Fusão Vertebral , Tantálio , Fenômenos Biomecânicos , Fusão Vertebral/métodos , Placas Ósseas , Análise de Elementos Finitos , Impressão Tridimensional , Vértebras Lombares/cirurgia
19.
Micromachines (Basel) ; 15(7)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39064396

RESUMO

The problem that the conventional double-exponential transient current model (DE model) can overdrive the circuit, which leads to the overestimation of the soft error rate of the logic cell, is solved. Our work uses a new and accurate model for predicting the soft error rate that brings the soft error rate closer to the actual. The piecewise double-exponential transient current model (PDE model) is chosen, and the accuracy of the model is reflected using the Layout Awareness Single Event Multi Transients Soft Error Rate Calculation tool (LA-SEMT-SER tool). The model can characterize transient current pulses piecewise and limit the peak current magnitude to not exceed the conduction current. TCAD models are constructed from 28 nm process library and cell layouts. The transfer characteristic curves of devices are calibrated, and functional timing verification is performed to ensure the accuracy of the TCAD model. The experimental results show that the PDE model is not only more consistent with TCAD simulation than the DE model in modeling the single event transient currents of the device, but also that the SER calculated by the LA-SEMT-SER tool based on the PDE model has a smaller error than the SER calculated by the LA-SEMT-SER tool based on the DE model.

20.
Micromachines (Basel) ; 15(4)2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38675352

RESUMO

With the rapid development of semiconductor technology, the reduction in device operating voltage and threshold voltage has made integrated circuits more susceptible to the effects of particle radiation. Moreover, as process sizes decrease, the impact of charge sharing effects becomes increasingly severe, with soft errors caused by single event effects becoming one of the main causes of circuit failures. Therefore, the study of sensitivity evaluation methods for integrated circuits is of great significance for promoting the optimization of integrated circuit design, improving single event effect experimental methods, and enhancing the irradiation reliability of integrated circuits. In this paper, we first established a device model for the charge sharing effect and simulated it under reasonable conditions. Based on the simulation results, we then built a neural network model to predict the charge amounts in primary and secondary devices. We also propose a comprehensive automated method for calculating soft errors in unit circuits and validated it through TCAD simulations, achieving an error margin of 2.8-4.3%. This demonstrated the accuracy and effectiveness of the method we propose.

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