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Pollen protects male sperm and allows flowering plants to adapt to diverse terrestrial environments, thereby leading to the rapid expansion of plants into new regions. The process of anther/pollen development is coordinately regulated by internal and external factors including hormones. Currently, the molecular mechanisms underlying gibberellin (GA)-mediated male reproductive development in plants remain unknown. We show here that rice DELLA/SLR1, which encodes the central negative regulator of GA signaling, is essential for rice anther development. The slr1-5 mutant exhibits premature programmed cell death of the tapetum, lacks Ubisch bodies, and has no exine and no mature pollen. SLR1 is mainly expressed in tapetal cells and tetrads, and is required for the appropriate expression of genes encoding key factors of pollen development, which are suggested to be OsMS188-targeted genes. OsMS188 is the main component in the essential genetic program of tapetum and pollen development. Further, we demonstrate that SLR1 interacts with OsMS188 to cooperatively activate the expression of the sporopollenin biosynthesis and transport-related genes CYP703A3, DPW, ABCG15 and PKS1 for rapid formation of pollen walls. Overall, the results of this study suggest that the GA hormonal signal is integrated into the anther genetic program and regulates rice anther development through the GA-DELLA-OsMS188 module.
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Oryza , Regulación de la Expresión Génica de las Plantas , Mutación/genética , Oryza/metabolismo , Fenotipo , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Polen/metabolismoRESUMEN
Introduction: Timely and effective treatments of pericoronitis are very important. We aimed to evaluate the role of ornidazole in the treatment of pericoronitis, to provide insights for clinical pericoronitis treatment. Material and methods: The PubMed, Clinical trials, EMBASE, Science Direct, Cochrane Library, China National Knowledge Infrastructure (CNKI), Weipu and Wanfang databases were searched to find randomized controlled trials (RCTs) of ornidazole in the treatment of pericoronitis from the establishment of the database to March 15, 2023. Review Manager 5.3 software was used for meta-analysis. Results: A total of 16 RCTs involving 2004 patients were included. The results of the meta-analysis showed that the effective rate of ornidazole treatment was significantly higher than that of the routine treatment group (RR = 1.22, 95% CI (1.15, 1.29), p < 0.001). Ornidazole treatment was beneficial to reduce the oral bacterial density (MD = -26.13, 95% CI (-32.08, -21.51)), time to pain disappearance (MD = -0.64, 95% CI (-0.92, -0.17)) and time to disappearance of redness and swelling of the teeth crown (MD = -1.45, 95% CI (-2.43, -1.01)) compared to the routine treatment (all p = 0.05). No publication bias was found by the funnel plots and Egger test (p = 0.206). Conclusions: Ornidazole is effective in the treatment of pericoronitis, with more advantages. Still, the effects and safety of ornidazole in the treatment of pericoronitis need to be evaluated by more high-quality RCTs with larger sample sizes.
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BACKGROUND: In the context of the present global aging phenomenon, the senior population and pace of aging in China have emerged as prominent issues on the worldwide stage. Frailty, a complicated condition that is closely linked to the clinical syndrome of advancing age, poses a considerable health risk to older individuals. Frailty status was assessed by the frailty index (FI) ranging from 0 to 1, pre-frailty was defined as >0.10 to <0.25, and frailty was defined as ≥0.25. To look at the connection between modifiable risk factors and frailty progression among individuals in the pre-frailty population. METHODS: Using pre-frailty patients as characterized by the 32-frailty index, the study focused on middle-aged and elderly persons from China and ultimately recruited 5,411 participants for analysis. The relationship between modifiable factors and changes in pre-frailty status throughout follow-up was investigated. Modifiable factors were body mass index (BMI), abdominal obesity, smoking status, alcohol use, and sleep status. We employed logistic regression to examine the relationships between modifiable risk factors and changes in pre-frailty status, as well as the associations between modifiable factors scores and the corresponding pre-frailty progression. Additionally, we generated the modifiable factors scores and examined how these related to modifications in the pre-frailty stage. RESULTS: In this study, after a mean follow-up of 6 years, (OR = 0.59, 95%CI: 0.48-0.71) for BMI ≥ 25 kg/m2 and (OR = 0.74, 95%CI: 0.63-0.89) for concomitant abdominal obesity were significantly associated with lower reversal to a healthy state; (OR = 1.24, 95%CI:1.07-1.44) and (OR = 1.25, 95%CI: 1.10-1.42) for the group that negatively progressed further to frailty were significantly associated with increased frailty progression profile. Subsequently, investigation of modifiable factor scores and changes of pre-frailty status found that as scores increased further, frailty developed (OR = 1.12, 95%CI:1.05-1.18), with scores of 3 and 4 of (OR = 1.38, 95%CI: 1.08-1.77) and (OR = 1.52, 95%CI:1.09-2.14). Finally, we also performed a series of stratified analyses and found that rural unmarried men aged 45 to 60 years with less than a high school degree were more likely to develop a frailty state once they developed abdominal obesity. CONCLUSION: In pre-frailty individuals, maintaining more favorable controllable variables considerably enhances the chance of return to normal and, conversely, increase the risk of progressing to the frailty.
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Índice de Masa Corporal , Progresión de la Enfermedad , Anciano Frágil , Fragilidad , Evaluación Geriátrica , Humanos , Masculino , Factores de Riesgo , Fragilidad/epidemiología , Anciano , Femenino , Persona de Mediana Edad , China/epidemiología , Consumo de Bebidas Alcohólicas/epidemiología , Consumo de Bebidas Alcohólicas/efectos adversos , Modelos Logísticos , Fumar/epidemiología , Fumar/efectos adversos , Anciano de 80 o más Años , Obesidad Abdominal/epidemiología , Obesidad Abdominal/complicaciones , Sueño/fisiología , Envejecimiento/fisiologíaRESUMEN
Early assessment and accurate staging of liver fibrosis may be of great help for clinical diagnosis and treatment in patients with chronic hepatitis B (CHB). We aimed to identify serum markers and construct a machine learning (ML) model to reliably predict the stage of fibrosis in CHB patients. The clinical data of 618 CHB patients between February 2017 and September 2021 from Zhejiang Provincial People's Hospital were retrospectively analyzed, and these data as a training cohort to build the model. Six ML models were constructed based on logistic regression, support vector machine, Bayes, K-nearest neighbor, decision tree (DT) and random forest by using the maximum relevance minimum redundancy (mRMR) and gradient boosting decision tree (GBDT) dimensionality reduction selected features on the training cohort. Then, the resampling method was used to select the optimal ML model. In addition, a total of 571 patients from another hospital were used as an external validation cohort to verify the performance of the model. The DT model constructed based on five serological biomarkers included HBV-DNA, platelet, thrombin time, international normalized ratio and albumin, with the area under curve (AUC) values of the DT model for assessment of liver fibrosis stages (F0-1, F2, F3 and F4) in the training cohort were 0.898, 0.891, 0.907 and 0.944, respectively. The AUC values of the DT model for assessment of liver fibrosis stages (F0-1, F2, F3 and F4) in the external validation cohort were 0.906, 0.876, 0.931 and 0.933, respectively. The simulated risk classification based on the cutoff value showed that the classification performance of the DT model in distinguishing hepatic fibrosis stages can be accurately matched with pathological diagnosis results. ML model of five serum markers allows for accurate diagnosis of hepatic fibrosis stages, and beneficial for the clinical monitoring and treatment of CHB patients.
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Biomarcadores , Hepatitis B Crónica , Cirrosis Hepática , Aprendizaje Automático , Humanos , Cirrosis Hepática/sangre , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/patología , Hepatitis B Crónica/sangre , Hepatitis B Crónica/complicaciones , Hepatitis B Crónica/patología , Biomarcadores/sangre , Femenino , Masculino , Adulto , Persona de Mediana Edad , Estudios RetrospectivosRESUMEN
We report on the gas-phase structure of the most abundant conformer of diisopropyl ketone, (CH(3))(2)HC-CO-CH(CH(3))(2), as observed by molecular beam Fourier transform microwave spectroscopy. The gas-phase structures of five conformers of diisopropyl ketone were optimized using ab initio calculations at the MP2/6-311++G(d,p) level of theory. The natures of the stationary points were verified using harmonic frequency calculations. The only conformer observed in the supersonic jet possesses C(2) symmetry and appears as an enantiomeric pair. From the microwave spectrum, a set of three highly accurate rotational constants, five centrifugal distortion constants, and three sextic centrifugal distortion constants were determined. The structure of the observed conformer was optimized again at different levels of theory using the HF, MP2, and B3LYP methods. The theoretical constants of the C(2) conformer were subsequently validated using the experimental constants. To understand the transitions of one conformer to the others, the isopropyl groups were rotated against each other. The resulting two-dimensional potential energy surface shows nicely the symmetry of the conformational landscape and also indicates the enantiomeric pairs of the conformers. The barriers to internal rotation of the methyl groups were determined to be 1052 and 905 cm(-1) at the MP2/6-311++G(d,p) and the B3LYP/6-311++G(d,p) levels, respectively. In agreement with the theoretical predictions, no internal rotation patterns could be observed in the microwave spectrum.
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Aim: In clinical practice, a considerable proportion of patients with chronic hepatitis B (CHB) who do not conform to any immune status are considered to be in the "indeterminate phase". In this study, we aim to study the clinical distribution characteristics and identification of significant liver inflammation in patients in indeterminate phase. Methods: This study retrospectively analyze clinical data of 1226 patients with CHB at two medical centers in Zhejiang province. According to American Association for the Study of Liver Diseases (AASLD) 2018 hepatitis B guidance, CHB can be divided into four phases: immune-tolerant phase, HBeAg-positive immune active phase, inactive phase, and HBeAg-negative immune active phase. Liver inflammation grade was evaluated using the Scheuer scoring system, and significant liver inflammation was defined as G ≥ 2. Results: The distribution of different immune status was as follows: 259 (21.1%) patients in immune-tolerant phase, 365 (29.8%) patients in HBeAg-positive immune active phase, 128 (10.4%) patients in inactive phase, and 33 (2.7%) patients in HBeAg-negative immune active phase. However, 441 (36.0%) patients did not meet any of the above immune phases, which were defined as indeterminate phase. Significant liver inflammation (54.1%) was common in CHB patients with indeterminate phase. Prothrombin time (PT), platelet count (PLT), alanine aminotransferase (ALT), and hepatitis B virus (HBV)-DNA were associated with significant inflammation. Conclusions: The results of this study showed that about 36.0% of patients were divided into indeterminate phase. The proportion of patients with significant inflammation in indeterminate phase and liver inflammation becomes more severe with aggravation of fibrosis stage. PT, PLT, ALT, and HBV-DNA may have a significant correlation with severe inflammation and prognosis of CHB.
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Highly sensitive and reliable detection of ß-adrenergic agonists is especially necessary due to the illegal abuse of growth-promoting feed additives. Here, we develop a novel surface plasmon resonance/surface-enhanced Raman scattering (SPR/SERS) dual-mode plasmonic sensor based on core-satellite nanoassemblies for the highly sensitive and reliable detection of ractopamine (RAC). The addition of RAC results in the decomposition of core-satellite nanoassemblies and consequently changes the Rayleigh scattering color of dark-field microscopy (DFM) images and the Raman scattering intensity of SERS spectra. The excellent sensitivity, specificity, and uniformity of this strategy were confirmed by detecting RAC in various complex media in the farm-to-table chain, and the limit of detection (LOD) was 0.03 ng/mL in an aqueous solution. In particular, the convenient access to livestock sewage not only ensures animal welfare but also provides great convenience for the market regulation of ß-agonists. The success of our on-site strategy only with a portable Raman device promises great application prospects for ß-agonist detection.
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Nanopartículas del Metal , Resonancia por Plasmón de Superficie , Animales , Resonancia por Plasmón de Superficie/métodos , Oro , Espectrometría Raman/métodosRESUMEN
Bloodstream infections are serious and complex infectious diseases that often require a rapid diagnosis. Polymerase chain reaction coupled with quantum dot fluorescence analysis (PCR-QDFA) is a novel diagnostic technique. This study aimed to evaluate the diagnostic performance of PCR-QDFA for pathogen detection in patients with suspected bloodstream infections (BSIs). It evaluates 29 kinds of common pathogens (24 bacteria and 5 yeasts) from blood culture bottles. The results of PCR-QDFA identification and traditional microbial laboratory identification were compared, and the latter was used as the 'gold standard' to analyse the diagnostic performance of the PCR-QDFA. In total, 517 blood culture bottles were included in this study. The PCR-QDFA identified microorganisms in 368/422 (87.2%) samples with monomicrobial growth. For the pathogens on the PCR-QDFA list, the assay showed a higher sensitivity of 97.4% (368/378). When polymicrobial growth was analysed, the PCR-QDFA successfully detected 19/25 (76%) microorganisms on the PCR-QDFA list. In addition, 82/82 negative blood culture bottles also showed no pathogens by PCR-QDFA with a specificity of 100%. In conclusion, the PCR-QDFA assay could identify a majority of the common pathogens encountered in clinical practice, showing excellent diagnostic performance for pathogen detection in patients with suspected BSIs.
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Puntos Cuánticos , Sepsis , Humanos , Sepsis/diagnóstico , Bacterias/genética , Reacción en Cadena de la Polimerasa/métodos , Levaduras/genética , Sensibilidad y EspecificidadRESUMEN
Background: Persistence of long-term COVID-19 pandemic is putting high pressure on healthcare services worldwide for several years. This article aims to establish models to predict infection levels and mortality of COVID-19 patients in China. Methods: Machine learning models and deep learning models have been built based on the clinical features of COVID-19 patients. The best models are selected by area under the receiver operating characteristic curve (AUC) scores to construct two homogeneous ensemble models for predicting infection levels and mortality, respectively. The first-hand clinical data of 760 patients are collected from Zhongnan Hospital of Wuhan University between 3 January and 8 March 2020. We preprocess data with cleaning, imputation, and normalization. Results: Our models obtain AUC = 0.7059 and Recall (Weighted avg) = 0.7248 in predicting infection level, while AUC=0.8436 and Recall (Weighted avg) = 0.8486 in predicting mortality ratio. This study also identifies two sets of essential clinical features. One is C-reactive protein (CRP) or high sensitivity C-reactive protein (hs-CRP) and the other is chest tightness, age, and pleural effusion. Conclusions: Two homogeneous ensemble models are proposed to predict infection levels and mortality of COVID-19 patients in China. New findings of clinical features for benefiting the machine learning models are reported. The evaluation of an actual dataset collected from January 3 to March 8, 2020 demonstrates the effectiveness of the models by comparing them with state-of-the-art models in prediction.
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Liver fibrosis is a chronic liver injury that leads to liver cirrhosis and liver cancer. Ring finger protein 20 (RNF20), also named as E3 ubiquitin-protein ligase BRE1A, has been reported to be involved in chronic liver diseases. However, the role of RNF20 in liver fibrosis remains unclear. To mimic liver fibrosis in vitro, LX-2 cells were treated with TGF-ß. Gene and protein expressions were detected by RT-qPCR and western blot, respectively. The mechanism by which RNF20 mediated the progression of liver fibrosis was explored by bioinformatics analysis. Finally, in vivo mouse model of liver fibrosis was established to detect the function of RNF20. The results indicated that TGF-ß-induced increase of cell viability and migration was significantly reversed by RNF20 overexpression. Consistently, overexpression of RNF20 significantly reversed TGF-ß-induced activation of fibrotic proteins in LX-2 cells. Meanwhile, VEGFA, TNF-α and IL-6 were found to be the downstream targets of RNF20 in LX-2 cells. Moreover, RNF20 overexpression notably inhibited the progression of liver fibrosis via ubiquitination of H2B. Finally, RNF20 upregulation significantly attenuated the symptom of liver fibrosis in vivo. In summary, overexpression of RNF20 significantly inhibited the progression of liver fibrosis in vitro and in vivo. Therefore, RNF20 might serve as a new target for the treatment of liver fibrosis.
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Expresión Génica/genética , Expresión Génica/fisiología , Histonas/metabolismo , Cirrosis Hepática/genética , Cirrosis Hepática/prevención & control , Lisina/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Ubiquitinación/genética , Movimiento Celular/efectos de los fármacos , Movimiento Celular/genética , Supervivencia Celular/efectos de los fármacos , Supervivencia Celular/genética , Células Cultivadas , Progresión de la Enfermedad , Humanos , Interleucina-6/metabolismo , Cirrosis Hepática/patología , Factor de Crecimiento Transformador beta/farmacología , Factor de Necrosis Tumoral alfa/metabolismo , Ubiquitina-Proteína Ligasas/fisiología , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
PURPOSE: Gastric cancer (GC) is a serious threat to human health. We aimed to explore the effects of Wnt1 induced signaling protein 1 (WISP1) on GC. METHODS: The WISP1 expressions in GC tissues were detected using immunohistochemistry and qRT-PCR. The connection between GC prognosis and WISP1 expression was analyzed via Pearson's χ2 test. The WISP1 expressions were down-regulated in GC cells through siWISP1 transfection. Colony formation assay and cell counting kit-8 assay were carried out to measure cell colony formation and proliferation, respectively. Flow cytometry was operated to examine the cell cycle and apoptosis. The protein expressions in our study were assessed using western blot. The AKT pathway was blocked by LY294002 treatment and then the cell activities were assessed. Furthermore, GC mice models were established to investigate the effects of WISP1 on GC in vivo. RESULTS: We found that WISP1 was highly expressed in GC cells and tissues. The up-regulation of WISP1 was related to poor prognosis of GC patients. WISP1 down-regulation reduced colony formation and cell proliferation, resulted cell cycle arrest and promoted cell apoptosis in GC. WISP1 knockdown suppressed AKT/mTOR pathway activity. LY294002 treatment recovered the decreases of colony formation and cell proliferation, arrest of cell cycle and increase of cell apoptosis which were induced by WISP1 knockdown. WISP1 down-regulation repressed GC tumor growth and enhanced tumor apoptosis in vivo. CONCLUSION: WISP1 regulated GC cell proliferation and apoptosis in vivo and in vitro through activating AKT/mTOR pathway. WISP1 might be a target in GC therapy.
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Cisplatin- (CDDP) induced acute kidney injury (AKI) limits the clinical use of cisplatin. Several sirtuin (SIRT) family proteins are involved in AKI, while the roles of Sirt5 in cisplatin-induced AKI remain unknown. In the present study, we characterized the role and mechanism of Sirt5 in cisplatin-induced apoptosis using the human kidney 2 (HK-2) cell line. CDDP treatment decreased Sirt5 expression of HK-2 cells in a dose-dependent manner. In addition, Sirt5 overexpression enhanced the metabolic activity in CDDP-treated HK-2 cells while Sirt5 siRNA attenuated it. Forced expression of Sirt5 inhibited CDDP-induced apoptosis while Sirt5 siRNA showed the opposite effects. Accordingly, Sirt5 overexpression inhibited the level of caspase 3 cleavage and cytochrome c levels. Furthermore, we found that Sirt5 increased mitochondrial membrane potentials and ameliorated intracellular ROS production. Mitotracker Red staining indicated that Sirt5 overexpression was able to maintain the mitochondrial density during CDDP treatment. We also investigated possible downstream targets of Sirt5 and found that Sirt5 increased Nrf2, HO-1, and Bcl-2 while it decreased Bax protein expression. Sirt5 siRNA showed the opposite effect on these proteins. The levels of Nrf2, HO-1, and Bcl-2 proteins in HK-2 cells were also decreased after CDDP treatment. Moreover, Nrf2 and Bcl-2 siRNA partly abolished the protecting effect of Sirt5 on CDDP-induced apoptosis and cytochrome c release. Catalase inhibitor 3-AT also abolished the cytoprotective effect of Sirt5. Together, the results demonstrated that Sirt5 attenuated cisplatin-induced apoptosis and mitochondrial injury in human kidney HK-2 cells, possibly through the regulation of Nrf2/HO-1 and Bcl-2.
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Lesión Renal Aguda/metabolismo , Cisplatino/efectos adversos , Hemo-Oxigenasa 1/metabolismo , Factor 2 Relacionado con NF-E2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Sirtuinas/metabolismo , Sirtuinas/farmacología , Lesión Renal Aguda/inducido químicamente , Apoptosis/efectos de los fármacos , Caspasa 3 , Línea Celular , Humanos , Riñón/efectos de los fármacos , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Mitocondrias/metabolismoRESUMEN
Galectin-3 is a vital biomarker for cancer progression. An aggregation-induced emission (AIE)-active nanoparticle probe is designed and synthesized for label-free detection of galectin-3 based on carbohydrate-protein interactions. The probe employs tetraphenylethene (TPE) as the fluorescent core structure and N-acetyllactosamine (LacNAc) as galactoside residues and self-aggregates into uniform nanoparticles with multiple binding sites on the surface targeting galectin-3. Upon crosslinking of the nanoparticles and galectin-3, large complexes are formed and a significant fluorescence change is measured, allowing rapid, sensitive and specific detection of galectin-3 via a fluorometric assay. Its demonstrated superior anti-interference ability and applicability in serum samples offer promising applications in cancer diagnoses.
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Galectina 3/química , Nanopartículas/química , Estilbenos/química , Proteínas Sanguíneas , Fluorescencia , Galectinas , HumanosRESUMEN
Controlling the differentiation of stem cells and monitoring cell differentiation has attracted much research interest since the discovery of stem cells. In this regard, a novel near-infrared (NIR) light-activated nanoplatform is obtained by encapsulating the photoactivatable caged compound (DMNPE/siRNA) and combining a MMP13 cleaved imaging peptide-tetrapheny-lethene (TPE) unit conjugated with the mesoporous silica-coated up-conversion nanoparticles (UCNPs) for the remote control of cell differentiation and, simultaneously, for the real-time monitoring of differentiation. Upon NIR light illumination, the photoactivated caged compound is activated, and the siRNA is released from UCNPs, allowing controlled differentiation of stem cells by light. More importantly, MMP13 enzyme triggered by osteogenic differentiation would effectively cleave the TPE probe peptide, thereby allowing the real-time monitoring of differentiation in living stem cells by aggregation-induced emission (AIE).
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Nanopartículas/química , ARN Interferente Pequeño/fisiología , Dióxido de Silicio/química , Células Madre/citología , Células Madre/efectos de los fármacos , Itrio/química , Biomarcadores/sangre , Diferenciación Celular/fisiología , Supervivencia Celular/efectos de los fármacos , Técnica del Anticuerpo Fluorescente , Humanos , Metaloproteinasa 13 de la Matriz/metabolismo , Fármacos Fotosensibilizantes/química , ARN Interferente Pequeño/genética , Células Madre/metabolismoRESUMEN
Fabrication of the helical fibers with sheath/core structure comprising 3D interconnected porous polystyrene (PS) and ductile polyvinylidene fluoride is inspired by coiled plant tendril. The key innovation point applied in this study is to produce a helical porous system based on sheath/core structure that can come into being a huge storage space in the sorption process for crude oil. More importantly, the mechanical properties confirm to have a more excellent improvement than that of the initial PS fibers, which make it become a possible candidate for the large-area sorption and reuse of crude oil from the ocean or industry. The bioinspired fabricating strategy opens a significant avenue between the coaxial electrospinning and crude oil contamination cleanup. It is also expected that the unique structure can make it a promising candidate for applications in energy conversion, tissue engineering, and intelligent devices.
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A tetraphenylethene derivative with a structure resembling Tamoxifen is designed and synthesized as a theranostic agent for cell imaging and anti-breast cancer therapy. Its high brightness, excellent photostability and long-term cell tracing properties enable elucidation of its working mechanism and hence provide new insights into drug development.
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Antineoplásicos/farmacología , Neoplasias de la Mama/diagnóstico por imagen , Neoplasias de la Mama/tratamiento farmacológico , Nanomedicina Teranóstica , Colorantes Fluorescentes , Humanos , Células MCF-7 , Estilbenos/farmacología , Tamoxifeno/farmacologíaRESUMEN
The exopolysaccharides from Arthrobacter sp. B4 (B4-EPS) exhibited an excellent chromium (VI) (Cr(VI)) removal capability without any pH adjustment, whereby 50mgL(-1) of Cr(VI) could be completely removed by 4gL(-1) of B4-EPS. The kinetics tests revealed that the first-order rate constant was 8.3×10(-5)s(-1) and the optimal reaction time was 720min. However, a low initial concentration of Cr(VI) (5-30mgL(-1)) would accelerate the reaction rate of Cr(VI) removal and shorten reaction time to less than 360min. Meanwhile, the X-ray photoelectron spectroscopy (XPS) and ultraviolet-visible (UV-vis) spectra indicated that Cr(VI) was reduced to Cr(III) by B4-EPS in accordance with the emergence of the green reaction products. Furthermore, the Fourier transform-infrared spectra (FT-IR) and nuclear magnetic resonance (NMR) showed that carboxyl and hydroxyl groups of B4-EPS contributed to Cr(VI) reduction. Additionally, a feasible scheme for Cr(VI) detoxification by oxidation and flocculation of B4-EPS is presented.
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Arthrobacter/química , Arthrobacter/metabolismo , Cromo/metabolismo , Polisacáridos Bacterianos/química , Polisacáridos Bacterianos/metabolismo , Floculación , Concentración de Iones de Hidrógeno , Inactivación Metabólica , Cinética , Espectroscopía de Resonancia Magnética , Oxidación-Reducción , Espectroscopía Infrarroja por Transformada de FourierRESUMEN
Two azide-functionalized tetraphenylethene derivatives with AIE features are synthesized and used as fluorescent agents for detecting S-phase DNA synthesis and cell proliferation based on EdU assay. Compared to the Alexa-azide dye, a commercial DNA bioprobe, the AIE fluorogens show better photostability and sensitivity, making them promising alternatives.