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1.
Allergol Immunopathol (Madr) ; 52(4): 84-90, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38970270

RESUMO

PURPOSE: To investigate the effect of metformin on gut microbiota imbalance in patients with type 2 diabetes mellitus (T2DM), and the value of probiotic supplementation. METHODS: A total of 84 newly diagnosed T2DM patients were randomly divided into probiotics group, metformin group, and control group, with 28 patients in each group. The blood glucose control, islet function, gut microbiota, and inflammatory factors were compared between three groups. RESULTS: After 3 months of treatment, fasting plasma glucose (FPG), 2-h postprandial plasma glucose (2-h PG), and glycosylated hemoglobin A1c (HbA1c) were evidently decreased in both probiotics and metformin groups (P < 0.05) and were lower than that in the control group prior to treatment. Besides, FPG, 2-h PG, and HbA1c were lower in the metformin group than that in the control group. FPG, 2-h PG, and HbA1c were further lower in the probiotic group than in the metformin group (P < 0.05). Fasting insulin (FINS) and islet ß cell (HOMA-ß) -function were dramatically increased in the same group (P < 0.05), while insulin-resistant islet ß cells (HOMA-IR) were significantly lower in the same group (P < 0.05); FINS and HOMA-ß were significantly higher, while HOMA-IR was significantly lower (P < 0.05) in both groups than in the control group prior to treatment. HOMA-IR was also lower in the probiotic group than in the metformin group after treatment (P < 0.05); the number of lactobacilli and bifidobacteria increased (P < 0.05) in both probiotic and metformin groups than in the control group prior to treatment, and the number of Enterobacteriaceae and Enterococcus was lower in the control group prior to treatment (P < 0.05). In addition, the number of lactobacilli and bifidobacteria was higher and the number of enterobacteria and enterococci was lower in the probiotic group than that in the metformin group after treatment, and the differences were statistically significant (P < 0.05). Lipopolysaccharide (LPS), interleukin 6 (IL-6), and C-reactive protein (CRP) levels were lower in both probiotic and metformin groups (P < 0.05). The serum LPS, IL-6, and CRP levels were lower in both probiotic and metformin groups, compared to the control group prior to the treatment (P < 0.05). CONCLUSION: Metformin while treating T2DM assists in improving the imbalance of gut microbiota.


Assuntos
Glicemia , Diabetes Mellitus Tipo 2 , Microbioma Gastrointestinal , Hemoglobinas Glicadas , Hipoglicemiantes , Metformina , Probióticos , Humanos , Metformina/farmacologia , Metformina/administração & dosagem , Probióticos/administração & dosagem , Diabetes Mellitus Tipo 2/tratamento farmacológico , Diabetes Mellitus Tipo 2/imunologia , Diabetes Mellitus Tipo 2/terapia , Diabetes Mellitus Tipo 2/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/imunologia , Masculino , Feminino , Pessoa de Meia-Idade , Hipoglicemiantes/farmacologia , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/uso terapêutico , Hemoglobinas Glicadas/metabolismo , Glicemia/efeitos dos fármacos , Adulto , Suplementos Nutricionais , Insulina/sangue , Idoso
2.
Trials ; 25(1): 422, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38943177

RESUMO

BACKGROUND: Bladder dysfunction, notably urinary retention, emerges as a significant complication for cervical cancer patients following radical hysterectomy, predominantly due to nerve damage, severely impacting their postoperative quality of life. The challenges to recovery include insufficient pelvic floor muscle training and the negative effects of prolonged postoperative indwelling urinary catheters. Intermittent catheterization represents the gold standard for neurogenic bladder management, facilitating bladder training, which is an important behavioral therapy aiming to enhance bladder function through the training of the external urethral sphincter and promoting the recovery of the micturition reflex. Nevertheless, gaps remain in current research regarding optimal timing for intermittent catheterization and the evaluation of subjective symptoms of bladder dysfunction. METHODS: Cervical cancer patients undergoing laparoscopic radical hysterectomy will be recruited to this randomized controlled trial. Participants will be randomly assigned to either early postoperative catheter removal combined with intermittent catheterization group or a control group receiving standard care with indwelling urinary catheters. All these patients will be followed for 3 months after surgery. The study's primary endpoint is the comparison of bladder function recovery rates (defined as achieving a Bladder Function Recovery Grade of II or higher) 2 weeks post-surgery. Secondary endpoints include the incidence of urinary tract infections, and changes in urodynamic parameters, and Mesure Du Handicap Urinaire scores within 1 month postoperatively. All analysis will adhere to the intention-to-treat principle. DISCUSSION: The findings from this trial are expected to refine clinical management strategies for enhancing postoperative recovery among cervical cancer patients undergoing radical hysterectomy. By providing robust evidence, this study aims to support patients and their families in informed decision-making regarding postoperative bladder management, potentially reducing the incidence of urinary complications and improving overall quality of life post-surgery. TRIAL REGISTRATION: ChiCTR2200064041, registered on 24th September, 2022.


Assuntos
Remoção de Dispositivo , Histerectomia , Cateterismo Uretral Intermitente , Laparoscopia , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Bexiga Urinária , Cateteres Urinários , Neoplasias do Colo do Útero , Humanos , Histerectomia/efeitos adversos , Histerectomia/métodos , Feminino , Bexiga Urinária/fisiopatologia , Laparoscopia/efeitos adversos , Neoplasias do Colo do Útero/cirurgia , Cateterismo Uretral Intermitente/efeitos adversos , Fatores de Tempo , Remoção de Dispositivo/efeitos adversos , Resultado do Tratamento , Qualidade de Vida , Urodinâmica , Pessoa de Meia-Idade , Retenção Urinária/etiologia , Retenção Urinária/terapia , Retenção Urinária/fisiopatologia , Adulto , Cateterismo Urinário , Cateteres de Demora
3.
Sci Rep ; 14(1): 13167, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38849513

RESUMO

Exploring the spatial coupling relationship and interaction mechanism between green urbanization (GU) and tourism competitiveness (TC) is of great significance for promoting urban sustainable development. However, the lack of research on the interaction mechanism between GU and TC limits the formulation of effective environmental management policy and urban planning. Taking 734 counties in the Yellow River Basin (YRB) as the study area, this paper analyzes the spatial coupling relationship between GU and TC on the basis of comprehensive evaluation of GU and TC. Then, the interactive mechanism between GU and TC is systematically discussed, and the synergistic development strategy of the two is proposed. The results show that the GU level presents a multicore circle structure, with provincial capitals, prefecture-level urban districts and economically developed counties in east-central regions as high-value centers. The TC at county scale presents a multi-center spatial structure. Additionally, there is a significant positive spatial coupling between GU and TC in the YRB. The analysis further reveals that green urbanization level, social progress, population development, infrastructure construction, economic development quality, and eco-environmental protection has a observably influence on TC. Tourism competitiveness, service competitiveness, location competitiveness, resource competitiveness, market competitiveness, environmental influence, and talent competitiveness has a observably influence on GU. TC can promote GU, and the improvement of green urbanization level can support the development of tourism competitiveness. According to the spatial zoning method, 734 counties are divided into 6 categories, and the coordinated development strategy of GU and TC for each type of district is proposed.

4.
J Colloid Interface Sci ; 672: 338-349, 2024 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-38850861

RESUMO

Phase change materials (PCMs) can store and release latent heat under the designed phased change temperature and have received substantial interest for energy conservation and thermal control purposes. The use of PCMs in the construction of constant temperature buildings can improve the comfortable environment and save more energy. However, the leakage of PCMs during phase change process limits the application of PCMs. In this paper, a series of PCMs microcapsules with controllable core numbers is synthesized with paraffin (37 ℃) as the core and cross-linked chitosan as the wall. The single-core phase-change microcapsules (S-PCM) and multicore phase-change microcapsules (M-PCM) were prepared by adjusting the preparation condition. The latent heat of S-PCM and M-PCM are 61.4 mJ mg-1 and 50.1 mJ mg-1, respectively. The S-PCM and M-PCM display good stability without paraffin leakage. In addition, the composite blocks of gypsum and S-PCM (GSCM) and M-PCM (GMCM) were prepared and the thermoregulatory effection was investigated, where the surface temperature of GSCM was 5-10 ℃ lower than that of pure gypsum block. PCMs may also have broad application space in electronics, cold chain, and other industries.

5.
Nanomicro Lett ; 16(1): 221, 2024 Jun 17.
Artigo em Inglês | MEDLINE | ID: mdl-38884840

RESUMO

Considering the serious electromagnetic wave (EMW) pollution problems and complex application condition, there is a pressing need to amalgamate multiple functionalities within a single substance. However, the effective integration of diverse functions into designed EMW absorption materials still faces the huge challenges. Herein, reduced graphene oxide/carbon foams (RGO/CFs) with two-dimensional/three-dimensional (2D/3D) van der Waals (vdWs) heterostructures were meticulously engineered and synthesized utilizing an efficient methodology involving freeze-drying, immersing absorption, secondary freeze-drying, followed by carbonization treatment. Thanks to their excellent linkage effect of amplified dielectric loss and optimized impedance matching, the designed 2D/3D RGO/CFs vdWs heterostructures demonstrated commendable EMW absorption performances, achieving a broad absorption bandwidth of 6.2 GHz and a reflection loss of - 50.58 dB with the low matching thicknesses. Furthermore, the obtained 2D/3D RGO/CFs vdWs heterostructures also displayed the significant radar stealth properties, good corrosion resistance performances as well as outstanding thermal insulation capabilities, displaying the great potential in complex and variable environments. Accordingly, this work not only demonstrated a straightforward method for fabricating 2D/3D vdWs heterostructures, but also outlined a powerful mixed-dimensional assembly strategy for engineering multifunctional foams for electromagnetic protection, aerospace and other complex conditions.

6.
Int J Biol Macromol ; 273(Pt 1): 133041, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38857720

RESUMO

The effects of soluble dietary fiber (SDF) from pomegranate peel obtained through enzyme (E-SDF) and alkali (A-SDF) extractions on the structural, physicochemical properties, and in vitro digestibility of sweet potato starch (SPS) were investigated. The expansion degree of SPS granules, pasting viscosity, gel strength and hardness were decreased after adding E-SDF. The setback was accelerated in the presence of A-SDF but E-SDF delayed this effect during the cooling of the starch paste. However, the addition of A-SDF significantly reduced the breakdown of SPS and improved the freeze-thaw stability of starch gels, even at low concentrations (0.1 %), while E-SDF showed the opposite result. The structural characterization of SDF-SPS mixtures showed that A-SDF can help SPS form an enhanced microstructure compared with E-SDF, while polar groups such as hydroxyl group in E-SDF may bind to leached amylose through hydrogen bonding, leading to a decrease in SPS viscoelasticity. In addition, the results of in vitro digestion analysis indicated that A-SDF and E-SDF could decreased the digestibility of SPS and increased the content of resistant starch, especially when 0.5 % E-SDF was added. This study provides a new perspective on the application of SDF from pomegranate peel in improving starch-based foods processing and nutritional characteristics.


Assuntos
Fibras na Dieta , Ipomoea batatas , Punica granatum , Solubilidade , Amido , Ipomoea batatas/química , Punica granatum/química , Amido/química , Amido/metabolismo , Viscosidade , Fenômenos Químicos , Digestão
7.
Postgrad Med ; 136(4): 422-429, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38773675

RESUMO

BACKGROUND: Whether there is a longitudinal association between long-term blood pressure variability (BPV) and subsequent depression among Chinese adults remains inconclusive. METHODS: This study utilized data from a nationwide cohort of the China Health and Retirement Longitudinal Study, which included participants aged > 45 years without prevalent psychiatric or memory-related diseases. The intra-individual coefficient of variation (CV) and standard deviation (SD) across 3 visits from 2011 to 2015 were used to examine the long-term variability in systolic BP (SBP) and diastolic BP (DBP). The depressive symptoms were examined using the 10-item Center for Epidemiologic Studies Depression Scale (CES-D-10), and moderate-to-severe depression was defined as CES-D-10 ≥ 15. RESULTS: A total of 5,249 participants (mean age: 61.4 ± 8.1 years, 46.5% were men) were included in the current analysis. Individuals in the highest quartile of both BP CV and SD were independently correlated with a higher total CES-D-10 score compared to those in the lowest quartile after multivariable adjustment. 1,070 participants (20.4%) had moderate-to-severe depression during the 3-year follow-up period. Participants in the Q4 of SBP and DBP CV had 1.23-fold higher odds (95% CI: 1.01, 1.49) and 1.20-fold higher odds (95% CI: 1.01, 1.41) of moderate-to-severe depression compared to those in Q1. Subgroup analyses revealed that men with higher BP CVs had a greater risk of severe depressive symptoms (p for SBP CV-by-sex interaction = 0.050, p for SBP CV-by-sex interaction = 0.025). CONCLUSIONS: Depression was common among Chinese middle-aged and older adults and long-term visit-to-visit BPV was positively associated with depressive symptoms, highlighting the importance of implementing intensive prevention strategies for depression and enhancing blood pressure monitors in China.


Assuntos
Pressão Sanguínea , Depressão , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , China/epidemiologia , Depressão/epidemiologia , Idoso , Pressão Sanguínea/fisiologia , Estudos Longitudinais , Hipertensão/epidemiologia , Hipertensão/fisiopatologia , Fatores de Risco , População do Leste Asiático
8.
Anal Chem ; 96(21): 8416-8423, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38755966

RESUMO

Nanogap-based plasmonic metal nanocrystals have been applied in surface-enhanced Raman scattering detection, while the closed and insufficient electromagnetic fields as well as the nonreproducible Raman signal of the substrate greatly restrict the actual application. Herein, a highly uniform Au/AgAu monolayer with abundant nanogaps and huge electromagnetic enhancement is prepared, which shows ultrasensitive and reproducible SERS detection. Au/AgAu with an inner nanogap is first prepared based on Au nanotriangles, and the nanogap is opened from the three tips via a subsequent etching process. The open-gap Au/AgAu displays much higher SERS efficiency than Au and Au/AgAu with an inner nanogap on detecting crystal violet due to the open-gap induced electromagnetic enhancement and improved molecular absorption. Furthermore, the open-gap Au/AgAu monolayer is prepared via interfacial self-assembly, which shows further improved SERS due to the dense and strong hotspots in the nanocavities induced by the electromagnetic coupling between adjacent open gaps. The monolayer possesses excellent signal stability, uniformity, and reproducibility. The analytic enhancement factor and relative standard deviation reach to 2.12 × 108 and 4.65% on detecting crystal violet, respectively. Moreover, the monolayer achieves efficient detection of thiram in apple juice, biphenyl-4-thiol, 4-mercaptobenzoic, melamine, and a mixed solution of four different molecules, showing great promise in practical detection.

10.
Retina ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38564760
11.
BMC Cancer ; 24(1): 411, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566028

RESUMO

BACKGROUND: Deleterious BRCA1/2 (BRCA) mutation raises the risk for BRCA mutation-related malignancies, including breast, ovarian, prostate, and pancreatic cancer. Germline variation of BRCA exhibits substantial ethnical diversity. However, there is limited research on the Chinese Han population, constraining the development of strategies for BRCA mutation screening in this large ethnic group. METHODS: We profile the BRCA mutational spectrum, including single nucleotide variation, insertion/deletion, and large genomic rearrangements in 2,080 apparently healthy Chinese Han individuals and 522 patients with BRCA mutation-related cancer, to determine the BRCA genetic background of the Chinese Han population, especially of the East Han. Incident cancer events were monitored in 1,005 participants from the healthy group, comprising 11 BRCA pathogenic/likely pathogenic (PLP) variant carriers and 994 PLP-free individuals, including 3 LGR carriers. RESULTS: Healthy Chinese Han individuals demonstrated a distinct BRCA mutational spectrum compared to cancer patients, with a 0.53% (1 in 189) prevalence of pathogenic/likely pathogenic (PLP) variant, alongside a 3 in 2,080 occurrence of LGR. BRCA1 c. 5470_5477del demonstrated high prevalence (0.44%) in the North Han Chinese and penetrance for breast cancer. None of the 3 LGR carriers developed cancer during the follow-up. We calculated a relative risk of 135.55 (95% CI 25.07 to 732.88) for the development of BRCA mutation-related cancers in the BRCA PLP variant carriers (mean age 42.91 years, median follow-up 10 months) compared to PLP-free individuals (mean age 48.47 years, median follow-up 16 months). CONCLUSION: The unique BRCA mutational profile in the Chinese Han highlights the potential for standardized population-based BRCA variant screening to enhance BRCA mutation-related cancer prevention and treatment.


Assuntos
Proteína BRCA1 , Neoplasias da Mama , Masculino , Humanos , Adulto , Pessoa de Meia-Idade , Proteína BRCA1/genética , Mutação em Linhagem Germinativa , Proteína BRCA2/genética , Predisposição Genética para Doença , Detecção Precoce de Câncer , China/epidemiologia , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/epidemiologia , Neoplasias da Mama/genética , Mutação
12.
Langmuir ; 40(16): 8327-8351, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38606587

RESUMO

High emission of carbon dioxide (CO2) has caused CO2 levels to reach more than 400 ppm in air and led to a serious climate problem. In addition, in confined spaces such as submarines and aircraft, the CO2 concentration increase in the air caused by human respiration also affects human health. In order to protect the environment and human health, the search for high-performance adsorbents for carbon capture from high and low concentration gas is particularly important. Porous carbon materials, possessing the advantages of low cost and renewability, have set off a boom in the research of porous adsorbents, which have the opportunity to be utilized on a large scale for industrial carbon capture in the future. In this review, we summarize the recent research progress of porous carbons for carbon capture from flue gas and directly from air in the last five years, including activated carbon (AC), heteroatom-modified porous carbon, carbon molecular sieves (CMS), and other porous carbon materials, with a focus on the effects of temperature, water content, and gas flow rate of industrial flue gas on the performance of porous carbon adsorbents. We summarize the preparation strategies of various porous carbons and seek environmental friendly porous carbon materials preparation strategies under the premise of improving the CO2 adsorption capacity and selectivity of porous carbon adsorbents. Based on the effects of real industrial flue gas on adsorbents, we provide new ideas and evaluation methods for the development and preparation of porous carbon materials.

13.
J Colloid Interface Sci ; 667: 362-370, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38640655

RESUMO

In this study, we employed a straightforward phosphorylation approach to achieve a dual objective: constructing c-a heterostructures consisting of crystalline Ni12P5 and amorphous FeOOH, while simultaneously enhancing oxygen vacancies. The resulting oxygen evolution reaction (OER) catalyst, Ni12P5/FeOOH/NF, exhibited remarkable performance with current densities of 500 mA cm-2 in both 1 M KOH and 1 M KOH + seawater, requiring low overpotentials of only 288 and 365 mV, respectively. Furthermore, Ni12P5/FeOOH/NF exhibited only a slight increase in overpotential, with increments of 18 mV and 70 mV in 1 M KOH after 15 and 150 h, and 32 mV and 108 mV in 1 M KOH + seawater at 500 mA cm-2 after 15 and 150 h, respectively. This minimal change can be attributed to the stabilized c-a structure, the protective coating of Ni12P5, and superhydrophilic. Through in-situ Raman and ex-situ XPS analysis, we discovered that Ni12P5/FeOOH/NF can undergo a reconfiguration into an oxygen vacancy-rich (Fe/Ni)OOH phase during OER process. The elevated OER activity is mainly due to the contribution of the oxygen vacancy-rich (Fe/Ni)OOH phase from the reconfigure of the Ni12P5/FeOOH/NF. This finding emphasizes the critical role of oxygen vacancies in facilitating the production of OO species and overcoming the limitations associated with OOH formation, ultimately enhancing the kinetics of the OER.

14.
Plant Physiol Biochem ; 208: 108509, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38461751

RESUMO

Melatonin (MT) and reduced glutathione (GSH) roles in mitigating chromium (Cr) toxicity in sweetpotato were explored. Plants, pre-treated with varying MT and GSH doses, were exposed to Cr (40 µM). Cr severely hampered growth by disrupting leaf photosynthesis, root system, and oxidative processes and increased Cr absorption. However, the exogenous application of 1 µM of MT and 2 mM of GSH substantially improved growth parameters by enhancing chlorophyll content, gas exchange (Pn, Tr, Gs, and Ci), and chlorophyll fluorescence (Fv/Fm, ETR, qP, and Y(II)). Furthermore, malondialdehyde (MDA), hydrogen peroxide (H2O2), superoxide ion (O2•-), electrolyte leakage (EL), and Cr uptake by roots (21.6 and 27.3%) and its translocation to shoots were markedly reduced by MT and GSH application, protecting the cell membrane from oxidative damage of Cr-toxicity. Microscopic analysis demonstrated that MT and GSH maintained chloroplast structure and integrity of mesophyll cells; they also enhanced stomatal length, width, and density, strengthening the photosynthetic system and plant growth and biomass. MT and GSH improved osmo-protectants (proline and soluble sugars), gene expression, and enzymatic and non-enzymatic antioxidant activities, mitigating osmotic stress and strengthening plant defenses under Cr stress. Importantly, the efficiency of GSH pre-treatment in reducing Cr-toxicity surpassed that of MT. The findings indicate that MT and GSH alleviate Cr detrimental effects by enhancing photosynthetic organ stability, component accumulation, and resistance to oxidative stress. This study is a valuable resource for plants confronting Cr stress in contaminated soils, but further field validation and detailed molecular exploration are necessary.


Assuntos
Melatonina , Melatonina/farmacologia , Cromo/toxicidade , Peróxido de Hidrogênio/metabolismo , Antioxidantes/metabolismo , Glutationa/metabolismo , Estresse Oxidativo , Fotossíntese , Clorofila/metabolismo
15.
Plant Biotechnol J ; 22(7): 1777-1796, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38348566

RESUMO

Heavy metal pollution poses a significant risk to human health and wreaks havoc on agricultural productivity. Phytoremediation, a plant-based, environmentally benign, and cost-effective method, is employed to remove heavy metals from contaminated soil, particularly in agricultural or heavy metal-sensitive lands. However, the phytoremediation capacity of various plant species and germplasm resources display significant genetic diversity, and the mechanisms underlying these differences remain hitherto obscure. Given its potential benefits, genetic improvement of plants is essential for enhancing their uptake of heavy metals, tolerance to harmful levels, as well as overall growth and development in contaminated soil. In this study, we uncover a molecular cascade that regulates cadmium (Cd2+) tolerance in cotton, involving GhRCD1, GhbHLH12, GhMYB44, and GhHMA1. We identified a Cd2+-sensitive cotton T-DNA insertion mutant with disrupted GhRCD1 expression. Genetic knockout of GhRCD1 by CRISPR/Cas9 technology resulted in reduced Cd2+ tolerance in cotton seedlings, while GhRCD1 overexpression enhanced Cd2+ tolerance. Through molecular interaction studies, we demonstrated that, in response to Cd2+ presence, GhRCD1 directly interacts with GhbHLH12. This interaction activates GhMYB44, which subsequently activates a heavy metal transporter, GhHMA1, by directly binding to a G-box cis-element in its promoter. These findings provide critical insights into a novel GhRCD1-GhbHLH12-GhMYB44-GhHMA1 regulatory module responsible for Cd2+ tolerance in cotton. Furthermore, our study paves the way for the development of elite Cd2+-tolerant cultivars by elucidating the molecular mechanisms governing the genetic control of Cd2+ tolerance in cotton.


Assuntos
Cádmio , Regulação da Expressão Gênica de Plantas , Gossypium , Proteínas de Plantas , Gossypium/genética , Gossypium/metabolismo , Cádmio/metabolismo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Biodegradação Ambiental , Plantas Geneticamente Modificadas , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética
16.
J Phys Condens Matter ; 36(30)2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38330447

RESUMO

Decoupling conductivity(σ)and Seebeck coefficient(S)by electronic topological transitions (ETT) under high pressure (2-4 GPa) is a promising method for bismuth telluride (Bi2Te3) to optimize thermoelectric (TE) performance. However, theScannot dramatically increase with increasingσwhen ETT occurs in Bi2Te3, which impedes optimizing TE performance by utilizing ETT in Bi2Te3. A new strategy of enhanced ETT by combining lattice distortions and high pressure is proposed in this work. The lattice distortions in Bi2Te3were introduced by high pressure and high temperature (HPHT) treatment to generate surplus dislocations. Thein-situmeasurements ofσandSat HPHT in Bi2Te3with lattice distortions show an enhanced ETT effect at 2 GPa, which causes decoupleσandSwith an anomalous increase in its|S|about 22%. The ETT effect causes the figure of merit (ZT) of Bi2Te3can be improved to 0.275 at 1.50-2.62 GPa, 460 K, it is more than 62% compared with 0.79 GPa, at 450 K. The excellent TE performance of Bi2Te3arising from the lattice distortions can result in local non-hydrostatic pressure which enhances ETT under high pressure. This work provides a new strategy to enhance ETT to decoupleσandS, and search for better TE materials from the pressure dimension in the future.

17.
IEEE Trans Pattern Anal Mach Intell ; 46(7): 4654-4668, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38252582

RESUMO

Nowadays, Deepfake videos are widely spread over the Internet, which severely impairs the public trustworthiness and social security. Although more and more reliable detectors have recently sprung up for resisting against that new-emerging tampering technique, some challengeable issues still need to be addressed, such that most of Deepfake video detectors under the framework of the supervised mechanism require a large scale of samples with accurate labels for training. When the amount of the training samples with the true labels are not enough or the training data are maliciously poisoned by adversaries, the supervised classifier is probably not reliable for detection. To tackle that tough issue, it is proposed to design a fully unsupervised Deepfake detector. In particular, in the whole procedure of training or testing, we have no idea of any information about the true labels of samples. First, we novelly design a pseudo-label generator for labeling the training samples, where the traditional hand-crafted features are used to characterize both types of samples. Second, the training samples with the pseudo-labels are fed into the proposed enhanced contrastive learner, in which the discriminative features are further extracted and continually refined by iteration on the guidance of the contrastive loss. Last, relying on the inter-frame correlation, we complete the final binary classification between real and fake videos. A large scale of experimental results empirically verify the effectiveness of our proposed unsupervised Deepfake detector on the benchmark datasets including FF++, Celeb-DF, DFD, DFDC, and UADFV. Furthermore, our proposed well-performed detector is superior to the current unsupervised method, and comparable to the baseline supervised methods. More importantly, when facing the problem of the labeled data poisoned by malicious adversaries or insufficient data for training, our proposed unsupervised Deepfake detector performs its powerful superiority.

18.
Chemistry ; 30(19): e202304081, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38288909

RESUMO

Optically pure sulfoxides are valuable organosulfur compounds extensively employed in medicinal and organic synthesis. In this study, we present a biocatalytic oxidation-reduction cascade system designed for the preparation of enantiopure sulfoxides. The system involves the cooperation of a low-enantioselective chimeric oxidase SMO (styrene monooxygenase) with a high-enantioselective reductase MsrA (methionine sulfoxide reductase A), facilitating "non-selective oxidation and selective reduction" cycles for prochiral sulfide oxidation. The regeneration of requisite cofactors for MsrA and SMO was achieved via a cascade catalysis process involving three auxiliary enzymes, sustained by cost-effective D-glucose. Under the optimal reaction conditions, a series of heteroaryl alkyl, aryl alkyl and dialkyl sulfoxides in R configuration were synthesized through this "one-pot, one step" cascade reaction. The obtained compounds exhibited high yields of >90 % and demonstrated enantiomeric excess (ee) values exceeding 90 %. This study represents an unconventional and efficient biocatalytic way in utilizing the low-enantioselective oxidase for the synthesis of enantiopure sulfoxides.


Assuntos
Metionina Sulfóxido Redutases , Sulfóxidos , Biocatálise , Oxirredução , Catálise , Estereoisomerismo
19.
Chemosphere ; 350: 141120, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38199502

RESUMO

Salt stress profoundly impacts sweetpotato production. Exogenous glutathione (GSH) and melatonin (MT) promoted plant growth under stress, but their specific roles and mechanisms in sweetpotato salt tolerance need exploration. This study investigated GSH and MT's regulatory mechanisms in sweetpotato under salt stress. Salt stress significantly reduces both growth and biomass by hindering photosynthesis, root traits, K+ content, and K+/Na+ balance, leading to oxidative stress and excessive hydrogen peroxide (H2O2), superoxide ion (O2•-), and malondialdehyde (MDA) production and Na+ accumulation. Nevertheless, GSH (2 mM) and MT (25 µM) pre-treatments effectively mitigated salt-induced oxidative damage and protected the plasma membrane. They reduced osmotic pressure by enhancing K+ uptake, K+/Na+ regulation, osmolyte accumulation, and reducing Na+ accumulation. Improved stomatal traits, chloroplast and grana lamella preservation, and maintenance of mesophyll cells, cell wall, and mitochondrial structure were observed with GSH and MT pre-treatments under salt stress, therefore boosting the photosynthetic system and enhancing plant growth and biomass. Moreover, the findings also indicate that the positive outcomes of GSH and MT pre-treatments result from elevated antioxidant levels, enhanced enzymatic activity, and upregulated expression of sodium hydrogen exchanger 2 (NHX2), K+transporter 1 (AKT1), and cation/H+exchanger (CHX), CBL-interacting protein kinase 1 (CIPK1), and antioxidant enzyme genes. These mechanisms enhance structural stability in photosynthesis and reduce salt stress. Evidently, MT pre-treatment exhibited superior effects compared to GSH. These findings provide a firm theoretical basis for employing GSH and MT to enhance salt tolerance in sweetpotato cultivation.


Assuntos
Melatonina , Melatonina/metabolismo , Antioxidantes/metabolismo , Espécies Reativas de Oxigênio/farmacologia , Tolerância ao Sal , Peróxido de Hidrogênio/metabolismo , Glutationa/metabolismo , Fotossíntese
20.
Anal Chim Acta ; 1287: 342103, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38182346

RESUMO

BACKGROUND: PLS-DA of high-dimensional metabolomics data is frequently employed to capture the most pertinent features to sample classification. But the presence of numerous insignificant input features could distort the PLS-DA model, blow up and scramble the selected differential features. Usually, univariate filtration is subsequently complemented to refine the selected features, but often giving unstable results. Whereas by precluding insignificant features through univariate data prefiltration assessed by FDR adjusted p-value, PLS-DA can generate more stable and reliable differential features. We explored and compared these two data analysis procedures to gain insights into the underlying mechanisms responsible for the disparate results. RESULTS: The effect of univariate data filtration preceding and succeeding PLS-DA analysis on the identified discriminative features/metabolites was investigated using LC-MS data acquired on the samples of human serum and C. elegans extracts, with and without metabolite standards spiked to simulate the treated and control groups of biological samples. It was shown that the univariate data prefiltration before PLS-DA usually gave less but more stable and likely more reliable and meaningful differential features, while PLS-DA applied directly to the original data could be affected by the presence of insignificant features and orthogonal noise. Large number of insignificant variables and orthogonal noise could distort the generated PLS-DA model and affect the p(corr) value, and artificially inflate the calculated VIP values of relevant features due to the increased total number of input features for model construction, thus leading to more false positives selected by the conventional VIP threshold of 1.0. SIGNIFICANCE AND NOVELTY: Univariate data filtration preceding PLS-DA was important for the identification of reliable differential features if using a conventional threshold of VIP of 1.0. Presence of insignificant features could distort the PLS-DA model and inflate VIP values. Appropriate VIP threshold is associated with the numbers of input features and the model components. For PLS-DA without univariate prefiltration, threshold of VIP larger than 1.0 is recommended for the selection of discriminative features to reduce the false positives.


Assuntos
Caenorhabditis elegans , Espectrometria de Massa com Cromatografia Líquida , Humanos , Animais , Cromatografia Líquida , Espectrometria de Massas em Tandem , Análise de Dados
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