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With the advantages of a Fenton-inactive characteristic and unique p electrons that can hybridize with O2 molecules, p-block metal-based single-atom catalysts (SACs) for the oxygen reduction reaction (ORR) have tremendous potential. Nevertheless, their undesirable intrinsic activity caused by the closed d10 electronic configuration remains a major challenge. Herein, an Sb-based SAC featuring carbon vacancy-enhanced Sb-N4 active centers, corroborated by the results of high-angle annular dark-field scanning transmission electron microscopy and X-ray absorption fine structure, has been developed for an incredibly effective ORR. The obtained SbSA-N-C demonstrates a positive half-wave potential of 0.905 V and excellent structural stability in alkaline environments. Density functional theory calculations reveal that the carbon vacancies weaken the adsorption between Sb atoms and the OH* intermediate, thus promoting the ORR performance. Practically, the SbSA-N-C-based Zn-air batteries achieve impressive outcomes, such as a high power density of 181 mW cm-2, showing great potential in real-world applications.
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Electrocatalytic nitric oxide (NO) reduction not only provides an extremely promising strategy for ambient NH3 generation but also alleviates the artificially disrupted N-cycle balance. However, exploring efficient electrocatalysts to enhance the NO electroreduction performance remains a significant challenge. Herein, a hexagonal-close-packed Co nanosheet (hcp-Co) is prepared and exhibits a high NH3 yield of 439.50 µmol cm-2 h-1 and a Faraday efficiency of 72.58%, outperforming the face-centered cubic phase of the Co nanosheet (fcc-Co) and most reported electrocatalysts. Through the combination of density functional theory calculations and NO temperature-programmed desorption experiments, the superior catalytic NO reduction reaction (NORR) activity on the hcp-Co can be attributed to the unique electron structures and proton shuttle effect. A proof-of-concept device of Zn-NO batteries using the hcp-Co as the cathode is assembled and shows a power density of 4.66 mW cm-2, which is superior to the reported performance in the literature so far.
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Some organic dyes and photosensitizers with strong visible absorption can behave as photo-responsive oxidase mimics. However, the relationship between the photo-oxidase activity and molecular structure remains unclear to date. In this work, a new type of photosensitizer with the characteristics of molecular rotors, namely DPPy, served as the molecular scaffold for further investigation. To adjust the photocatalytic oxidation ability, DAPy and CBPy were designed and synthesized based on the enhancement and diminishment of the intramolecular charge transfer (ICT) process, respectively. Kinetic studies revealed that DAPy and CBPy both exhibited highly efficient photo-activated oxidase-like activity with 3,3',5,5'-tetramethylbenzidine (TMB) as the substrate, which were in good accordance with their molecular engineering to promote either type I or type II reactive oxygen species (ROS) generation. Impressively a colorimetric method based on the visible light induced oxidase-like activity of molecular rotors was developed to determine the environmental temperature for the first time. Both DAPy and CBPy showed distinct sensitivities toward temperature as compared with several molecular rotors based on the typical fluorimetric detection. This work provides a new strategy for the application of molecular rotors to overcome the non-emissive challenge in temperature sensing.
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BACKGROUND: Hepatocellular carcinoma (HCC) is considered one of the most common cancers, characterized by low early detection and high mortality rates, and is a global health challenge. Immunogenic cell death (ICD) is defined as a specific type of regulated cell death (RCD) capable of reshaping the tumor immune microenvironment by releasing danger signals that trigger immune responses, which would contribute to immunotherapy. METHODS: The ICD gene sets were collected from the literature. We collected expression data and clinical information from public databases for the HCC samples in our study. Data processing and mapping were performed using R software to analyze the differences in biological characteristics between different subgroups. The expression of the ICD representative gene in clinical specimens was assessed by immunohistochemistry, and the role of the representative gene in HCC was evaluated by various in vitro assays, including qRT-PCR, colony formation, and CCK8 assay. Lasso-Cox regression was used to screen prognosis-related genes, and an ICD-related risk model (ICDRM) was constructed. To improve the clinical value of ICDRM, Nomograms and calibration curves were created to predict survival probabilities. Finally, the critical gene of ICDRM was further investigated through pan-cancer analysis and single-cell analysis. RESULTS: We identified two ICD clusters that differed significantly in terms of survival, biological function, and immune infiltration. As well as assessing the immune microenvironment of tumors in HCC patients, we demonstrate that ICDRM can differentiate ICD clusters and predict the prognosis and effectiveness of therapy. High-risk subpopulations are characterized by high TMB, suppressed immunity, and poor survival and response to immunotherapy, whereas the opposite is true for low-risk subpopulations. CONCLUSIONS: This study reveals the potential impact of ICDRM on the tumor microenvironment (TME), immune infiltration, and prognosis of HCC patients, but also a potential tool for predicting prognosis.
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Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/genética , Morte Celular Imunogênica , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/terapia , Tipagem Molecular , Calibragem , Microambiente Tumoral/genética , PrognósticoRESUMO
Insects have evolved effectors to conquer plant defense. Most known insect effectors are isolated from sucking insects, and examples from chewing insects are limited. Moreover, the targets of insect effectors in host plants remain unknown. Here, we address a chewing insect effector and its working mechanism. Cotton bollworm (Helicoverpa armigera) is a lepidopteran insect widely existing in nature and severely affecting crop productivity. We isolated an effector named HARP1 from H. armigera oral secretion (OS). HARP1 was released from larvae to plant leaves during feeding and entered into the plant cells through wounding sites. Expression of HARP1 in Arabidopsis mitigated the global expression of wounding and jasmonate (JA) responsive genes and rendered the plants more susceptible to insect feeding. HARP1 directly interacted with JASMONATE-ZIM-domain (JAZ) repressors to prevent the COI1-mediated JAZ degradation, thus blocking JA signaling transduction. HARP1-like proteins have conserved function as effectors in noctuidae, and these types of effectors might contribute to insect adaptation to host plants during coevolution.
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Gossypium/genética , Interações Hospedeiro-Parasita/genética , Mariposas/patogenicidade , Doenças das Plantas/genética , Animais , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Ciclopentanos/metabolismo , Resistência à Doença/genética , Regulação da Expressão Gênica de Plantas/genética , Gossypium/crescimento & desenvolvimento , Gossypium/parasitologia , Mariposas/metabolismo , Oxilipinas/metabolismo , Doenças das Plantas/parasitologia , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Transdução de Sinais/genéticaRESUMO
Gossypol and related sesquiterpene aldehydes in cotton function as defense compounds but are antinutritional in cottonseed products. By transcriptome comparison and coexpression analyses, we identified 146 candidates linked to gossypol biosynthesis. Analysis of metabolites accumulated in plants subjected to virus-induced gene silencing (VIGS) led to the identification of four enzymes and their supposed substrates. In vitro enzymatic assay and reconstitution in tobacco leaves elucidated a series of oxidative reactions of the gossypol biosynthesis pathway. The four functionally characterized enzymes, together with (+)-δ-cadinene synthase and the P450 involved in 7-hydroxy-(+)-δ-cadinene formation, convert farnesyl diphosphate (FPP) to hemigossypol, with two gaps left that each involves aromatization. Of six intermediates identified from the VIGS-treated leaves, 8-hydroxy-7-keto-δ-cadinene exerted a deleterious effect in dampening plant disease resistance if accumulated. Notably, CYP71BE79, the enzyme responsible for converting this phytotoxic intermediate, exhibited the highest catalytic activity among the five enzymes of the pathway assayed. In addition, despite their dispersed distribution in the cotton genome, all of the enzyme genes identified show a tight correlation of expression. Our data suggest that the enzymatic steps in the gossypol pathway are highly coordinated to ensure efficient substrate conversion.
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Gossipol/biossíntese , Gossipol/metabolismo , Vias Biossintéticas , Gossypium/metabolismo , Isomerases/biossíntese , Isomerases/metabolismo , Folhas de Planta/metabolismo , Sesquiterpenos Policíclicos , Sesquiterpenos/metabolismo , Transcriptoma/efeitos dos fármacosRESUMO
BACKGROUND: Cotton (Gossypium spp.) is the most important world-wide fiber crop but salt stress limits cotton production in coastal and other areas. Growth regulation factors (GRFs) play regulatory roles in response to salt stress, but their roles have not been studied in cotton under salt stress. RESULTS: We identified 19 GRF genes in G. raimondii, 18 in G. arboreum, 34 in G. hirsutum and 45 in G. barbadense, respectively. These GRF genes were phylogenetically analyzed leading to the recognition of seven GRF clades. GRF genes from diploid cottons (G. raimondii and G. arboreum) were largely retained in allopolyploid cotton, with subsequent gene expansion in G. barbadense relative to G. hirsutum. Most G. hirsutum GRF (GhGRF) genes are preferentially expressed in young and growing tissues. To explore their possible role in salt stress, we used qRT-PCR to study expression responses to NaCl treatment, showing that five GhGRF genes were down-regulated in leaves. RNA-seq experiments showed that seven GhGRF genes exhibited decreased expression in leaves under NaCl treatment, three of which (GhGRF3, GhGRF4, and GhGRF16) were identified by both RNA-seq and qRT-PCR. We also identified six and three GRF genes that exhibit decreased expression under salt stress in G. arboreum and G. barbadense, respectively. Consistent with its lack of leaf withering or yellowing under the salt treatment conditions, G. arboreum had better salt tolerance than G. hirsutum and G. barbadense. Our results suggest that GRF genes are involved in salt stress responses in Gossypium. CONCLUSION: In summary, we identified candidate GRF genes that were involved in salt stress responses in cotton.
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Regulação da Expressão Gênica de Plantas , Gossypium , Gossypium/genética , Gossypium/metabolismo , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Estresse SalinoRESUMO
Recently, a new class of lithium chlorides and bromides (e.g., Li3YCl6 and Li3YBr6) were reported to be promising solid-state electrolytes with high ionic conductivity in all-solid-state battery cells. However, their response under mechanical loading is not known which is critical as mechanical properties can play a pivotal role in reducing interfacing resistance between electrolytes and electrodes. To address this issue, herein, we report the thermo-physical properties of these lithium chlorides and bromides using density functional theory calculations. It was found that the new structures possess relatively larger shear moduli than those of thio-phosphate-type solid-state electrolytes and smaller Young's moduli than those of Garnet-type solid-state electrolytes. This suggests that the new halide materials can be more effective in suppressing the formation of lithium dendrites, accommodating volumetric changes of electrode materials and preventing their own degradation. Meanwhile, Poisson's ratio and Pugh's indicator calculations showed that Li3YCl6 and Li3ScCl6 possess improved ductility than other halide candidates, and thus hold promise as solid-state electrolytes. On the other hand, owing to their relatively high thermal conductivities, lithium bromides were found to be more advantageous in conducting heat which is important to ensure safety. These results provide fundamental insights into the mechanical properties of lithium chlorides and bromides and contribute to the rational mechanical design of solid-state electrolytes and the development advanced all-solid-state batteries.
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The electrochemical N2 fixation, which is far from practical application in aqueous solution under ambient conditions, is extremely challenging and requires a rational design of electrocatalytic centers. We observed that bismuth (Bi) might be a promising candidate for this task because of its weak binding with H adatoms, which increases the selectivity and production rate. Furthermore, we successfully synthesized defect-rich Bi nanoplates as an efficient noble-metal-free N2 reduction electrocatalyst via a low-temperature plasma bombardment approach. When exclusively using 1 Hâ NMR measurements with N2 gas as a quantitative testing method, the defect-rich Bi(110) nanoplates achieved a 15 NH3 production rate of 5.453â µg mgBi -1 h-1 and a Faradaic efficiency of 11.68 % at -0.6â V vs. RHE in aqueous solution at ambient conditions.
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OBJECTIVE: To investigate the effects of calcium-sensitive receptors (CaSR) on the expression of 11ß-hydroxysteroid dehydrogenase type 2 (11ß-HSD2) and cortisol concentration in a neonatal mouse model of persistent pulmonary hypertension (PPH). METHODS: Fifty-six newborn C57BL/6 mice were randomly divided into a control group (n=14), a PPH group (n=14), an agonist group (n=14), and an inhibitor group (n=14). The mice in the PPH, agonist, and inhibitor groups were exposed to a 12% oxygen concentration, and the agonist group and inhibitor group were given CaSR agonist (GdCl3, 16 mg/kg) and CaSR antagonist (NPS2390, 1 mg/kg) intraperitoneally once a day, respectively. The mice in control group were exposed to air, and then injected with an equal volume of normal saline as those in the PPH group every day. All mice were treated for 14 days. Morphological examination of heart and lung tissues was performed using hematoxylin-eosin staining. The expression levels of 11ß-HSD2 mRNA and 11ß-HSD2 protein in lung tissues were measured by qRT-PCR and Western blot respectively. Brain natriuretic peptide (BNP) and cortisol levels in lung tissues were determined using ELISA. RESULTS: Compared with the control group, the PPH group had significantly increased pulmonary artery wall thickness (WT%), ratio of right to left ventricular thickness (RV/LV), alveolar mean linear intercept, and BNP concentration and a significantly reduced radial alveolar count (P<0.05); compared with the PPH group, the agonist group showed significant increases in WT% and BNP concentration, while the inhibitor group showed significant reductions in the two indicators (P<0.05). Compared with the control group, the PPH group showed significant reductions in the expression levels of 11ß-HSD2 mRNA and 11ß-HSD2 protein, but a significant increase in cortisol concentration (P<0.05); compared with the PPH group, the agonist group had significantly lower expression levels of 11ß-HSD2 mRNA and 11ß-HSD2 protein, but a significant higher cortisol concentration, while the inhibitor group showed opposite changes in these indicators (P<0.05). CONCLUSIONS: CaSR may control the development and progression of PPH in newborn mice by regulating the expression of 11ß-HSD2 and cortisol concentration.
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Hipertensão Pulmonar , 11-beta-Hidroxiesteroide Desidrogenase Tipo 2 , Animais , Animais Recém-Nascidos , Cálcio , Hidrocortisona , Camundongos , Camundongos Endogâmicos C57BL , Receptores de Detecção de CálcioRESUMO
Cotton cultivars have evolved to produce extensive, long, seed-born fibers important for the textile industry, but we know little about the molecular mechanism underlying spinnable fiber formation. Here, we report how PACLOBUTRAZOL RESISTANCE 1 (PRE1) in cotton, which encodes a basic helix-loop-helix (bHLH) transcription factor, is a target gene of spinnable fiber evolution. Differential expression of homoeologous genes in polyploids is thought to be important to plant adaptation and novel phenotypes. PRE1 expression is specific to cotton fiber cells, upregulated during their rapid elongation stage and A-homoeologous biased in allotetraploid cultivars. Transgenic studies demonstrated that PRE1 is a positive regulator of fiber elongation. We determined that the natural variation of the canonical TATA-box, a regulatory element commonly found in many eukaryotic core promoters, is necessary for subgenome-biased PRE1 expression, representing a mechanism underlying the selection of homoeologous genes. Thus, variations in the promoter of the cell elongation regulator gene PRE1 have contributed to spinnable fiber formation in cotton. Overexpression of GhPRE1 in transgenic cotton yields longer fibers with improved quality parameters, indicating that this bHLH gene is useful for improving cotton fiber quality.
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Fibra de Algodão , Regulação da Expressão Gênica de Plantas , Variação Genética , Genoma de Planta , Sequências Reguladoras de Ácido Nucleico/genética , Fatores de Transcrição/genética , Sequência de Bases , Modelos Biológicos , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Poliploidia , Deleção de Sequência/genética , TATA Box/genética , Fatores de Transcrição/metabolismoRESUMO
Sodium-ion batteries (NIBs) and potassium-ion batteries (KIBs) have attracted increasing attention due to the high cost and finite abundance of lithium. Here, by using first-principles calculations, monolayer ß-GeSe has been found to be a promising anode material with a capacity of 353.65 mA h g-1 for both NIBs and KIBs. Additionally, the diffusions of Na and K over the monolayer ß-GeSe are ultrafast with small energy barriers of 0.080/0.125 eV and 0.052/0.047 eV for the Ge/Se side, respectively, indicating excellent rate performance. Monolayer ß-GeSe has low open circuit voltages of 0.219 V (vs. Na/Na+) and 0.030 V (vs. K/K+), which implies that the NIBs and KIBs could have high energy densities due to the high working voltages between the anode and cathode. Therefore, monolayer ß-GeSe as an anode material for NIBs and KIBs with excellent performance shows tremendous potential in the energy field.
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BACKGROUND: Although triptorelin is increasingly used in China for biochemical castration, its effects on primary prostate cancer symptoms remain unclear. This study aimed to assess the prevalence of lower urinary tract symptoms (LUTS) in Chinese prostate cancer patients and the effectiveness of triptorelin on LUTS. METHODS: In this 48-week multicenter, non-interventional, prospective study, we enrolled patients with locally advanced or metastatic prostate cancer. Patients received triptorelin (15 mg) intramuscularly at baseline and at weeks 12, 24, and 36 with symptom assessment using the International Prostate Symptoms Score (IPSS). The primary endpoints were the prevalence of LUTS at baseline per IPSS categories and the percentage of patients with moderate to severe LUTS (IPSS > 7) at baseline, having at least a 3-point reduction of IPSS score at week 48. RESULTS: A total of 398 patients were included; 211 (53.0%) and 160 (40.2%) among them had severe and moderate LUTS, respectively. Of the patients with IPSS scores available at baseline and at week 48 (n = 213), 81.2% achieved a reduction in IPSS of at least 3 points. Of the patients with moderate to severe LUTS at baseline and IPSS scores available at baseline and at week 48 (n = 194), 86.6% achieved a total IPSS reduction of at least 3 points. CONCLUSIONS: The vast majority of Chinese patients with locally advanced or metastatic prostate cancer scheduled to receive triptorelin as part of their standard treatment have severe or moderate LUTS. Triptorelin therapy resulted in sustained improvement of LUTS in these patients.
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Antineoplásicos Hormonais/administração & dosagem , Sintomas do Trato Urinário Inferior/tratamento farmacológico , Sintomas do Trato Urinário Inferior/epidemiologia , Neoplasias da Próstata/tratamento farmacológico , Neoplasias da Próstata/epidemiologia , Pamoato de Triptorrelina/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Humanos , Injeções Intramusculares , Sintomas do Trato Urinário Inferior/diagnóstico , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Neoplasias da Próstata/diagnósticoRESUMO
The Sabatier principle is widely explored in heterogeneous catalysis, graphically depicted in volcano plots. The most desirable activity is located at the peak of the volcano, and further advances in activity past this optimum are possible by designing a catalyst that circumvents the limitation entailed by the Sabatier principle. Herein, by density functional theory calculations, we discovered an unusual Sabatier principle on high entropy alloy (HEA) surface, distinguishing the "just right" (ΔGH* = 0 eV) in the Sabatier principle of hydrogen evolution reaction (HER). A new descriptor was proposed to design HEA catalysts for HER. As a proof-of-concept, the synthesized PtFeCoNiCu HEA catalyst endows a high catalytic performance for HER with an overpotential of 10.8 mV at -10 mA cm-2 and 4.6 times higher intrinsic activity over the state-of-the-art Pt/C. Moreover, the unusual Sabatier principle on HEA catalysts can be extended to other catalytic reactions.
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Patients with concurrent intrahepatic cholangiocarcinoma (ICC) and hepatolithiasis generally have poor prognoses. Hepatolithiasis is once considered the primary cause of ICC, although recent insights indicate that bacteria in the occurrence of hepatolithiasis can promote the progression of ICC. By constructing in vitro and in vivo ICC models and patient-derived organoids (PDOs), it is shown that Escherichia coli induces the production of a novel RNA, circGLIS3 (cGLIS3), which promotes tumor growth. cGLIS3 binds to hnRNPA1 and G3BP1, resulting in the assembly of stress granules (SGs) and suppression of hnRNPA1 and G3BP1 ubiquitination. Consequently, the IKKα mRNA is blocked in SGs, decreasing the production of IKKα and activating the NF-κB pathway, which finally results in chemoresistance and produces metastatic phenotypes of ICC. This study shows that a combination of Icaritin (ICA) and gemcitabine plus cisplatin (GP) chemotherapy can be a promising treatment strategy for ICC.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Progressão da Doença , Escherichia coli , NF-kappa B , Grânulos de Estresse , Animais , Humanos , Camundongos , Neoplasias dos Ductos Biliares/metabolismo , Neoplasias dos Ductos Biliares/genética , Neoplasias dos Ductos Biliares/patologia , Colangiocarcinoma/metabolismo , Colangiocarcinoma/genética , Colangiocarcinoma/patologia , Modelos Animais de Doenças , DNA Helicases , Escherichia coli/genética , Escherichia coli/metabolismo , Gencitabina , NF-kappa B/metabolismo , NF-kappa B/genética , Proteínas de Ligação a Poli-ADP-Ribose/metabolismo , Proteínas de Ligação a Poli-ADP-Ribose/genética , RNA Helicases , Proteínas com Motivo de Reconhecimento de RNA/metabolismo , Proteínas com Motivo de Reconhecimento de RNA/genética , Transdução de Sinais/genética , Grânulos de Estresse/metabolismo , Grânulos de Estresse/genéticaRESUMO
OBJECTIVE: To evaluate the safety and efficacy of regional citrate anticoagulation in sustained low efficiency dialysis (SLED). METHODS: A total of 45 patients with acute kidney injury (AKI) or end stage renal disease (ESRD) admitted in our hospital from August 2011 to September 2012 were prospectively enrolled in this study. All the patients received SLED treatment by Fresenius 4008sARrTplus dialyzer through either femoral or internal jugular venous catheter, with each session of SLED treatment lasting for 8 hours. All the patients were pumped in 4% tri-sodium citrate solution through the arterial line at 130 ml/hour and 10% calcium gluconate through the venous line at 40 ml/hour. The blood flow was 150 ml/minute while the calcium-free dialysate was delivered at 200 ml/minute. Systemic citrate concentration, peripheral and post dialyzer ionized calcium levels at 0, 2 and 5 hour were recorded. RESULTS: All the 45 patients underwent 162 sessions of SLED with 2 were discontinued due to III° dialyzer coagulation, and other 160 SLED sessions (98.8%) were all successfully performed. The systemic citrate concentration at 0 hour was (0.14 ± 0.06) mmol/L, the systemic citrate concentrations at 2 and 5 hour were slightly increased while no statistical difference was found[(1.08 ± 0.12) mmol/L vs (1.11 ± 0.17) mmol/L, P > 0.05]. The 0, 2, 5 hour peripheral blood ionized calcium levels were (1.04 ± 0.13) mmol/L, (1.07 ± 0.23) mmol/L and (1.04 ± 0.24) mmol/L, respectively, with no significant difference (P > 0.05). The post dialyzer ionized calcium levels were (0.31 ± 0.04) mmol/L at 2 hour and (0.29 ± 0.03) mmol/L at 5 hour. The transmembrane pressure at 2 hour was (104.5 ± 17.8) mm Hg(1 mm Hg = 0.133 kPa), and (109.3 ± 20.1) mm Hg at 5 hour, however the increase was not of statistical significance (P > 0.05). At 5 hour, prothrombin time and activated partial thrombin time were identified to be similar to those before SLED. During the treatments, no bleeding complication, thrombocytopenia, cardiac arrhythmia, hypernatremia, metabolic alkalosis or hypotension was observed. CONCLUSION: SLED under regional citrate anticoagulation is safe and effective. Citrate achieves satisfying regional anticoagulation effect without interfering systemic clotting function, thus this study provides a new option of SLED anticoagulation for clinicians.
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Anticoagulantes , Ácido Cítrico , Diálise Renal/métodos , Injúria Renal Aguda/terapia , Adulto , Idoso , Anticoagulantes/efeitos adversos , Anticoagulantes/uso terapêutico , Ácido Cítrico/efeitos adversos , Ácido Cítrico/uso terapêutico , Feminino , Humanos , Falência Renal Crônica/terapia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do TratamentoRESUMO
Active components with suitable supports are the common paradigm for industrial catalysis, and the catalytic activity usually increases with minimizing the active component size, generating a new frontier in catalysis, single-atom catalysts (SACs). However, further improvement of SACs activity is limited by the relatively low loading of single atoms (SAs, which are heteroatoms for most SACs, i.e., external active sites) because of the highly favorable aggregation of single heteroatoms during preparation. Research interest should be shifted to investigate SACs with intrinsic SAs, which could circumvent the aggregation of external SAs and consequently increase the SAs loading while maintaining them individual to further improve the activity. In this review, SACs with external or intrinsic SAs are discussed and, at last, the perspectives and challenges for obtaining high-loading SACs with intrinsic SAs are outlined.
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Axial chirality of biaryls can generate varied bioactivities. Gossypol is a binaphthyl compound made by cotton plants. Of its two axially chiral isomers, (-)-gossypol is the bioactive form in mammals and has antispermatogenic activity, and its accumulation in cotton seeds poses health concerns. Here we identified two extracellular dirigent proteins (DIRs) from Gossypium hirsutum, GhDIR5 and GhDIR6, which impart the hemigossypol oxidative coupling into (-)- and (+)-gossypol, respectively. To reduce cotton seed toxicity, we disrupted GhDIR5 by genome editing, which eliminated (-)-gossypol but had no effects on other phytoalexins, including (+)-gossypol, that provide pest resistance. Reciprocal mutagenesis identified three residues responsible for enantioselectivity. The (-)-gossypol-forming DIRs emerged later than their enantiocomplementary counterparts, from tandem gene duplications that occurred shortly after the cotton genus diverged. Our study offers insight into how plants control enantiomeric ratios and how to selectively modify the chemical spectra of cotton plants and thereby improve crop quality.
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Gossipol , Animais , Gossipol/toxicidade , Gossipol/análise , Gossipol/química , Edição de Genes , Gossypium/genética , Gossypium/metabolismo , Sementes/metabolismo , Mamíferos/genéticaRESUMO
Intrahepatic cholangiocarcinoma (ICC) is characterized by its dense fibrotic microenvironment and highly malignant nature, which are associated with chemotherapy resistance and very poor prognosis. Although circRNAs have emerged as important regulators in cancer biology, their role in ICC remains largely unclear. Herein, a circular RNA, cPKM is identified, which is upregulated in ICC and associated with poor prognosis. Silencing cPKM in ICC cells reduces TGFB1 release and stromal fibrosis, inhibits STMN1 expression, and suppresses ICC growth and metastasis, moreover, it also leads to overcoming paclitaxel resistance. This is regulated by the interactions of cPKM with miR-199a-5p or IGF2BP2 and by the ability of cPKM to stabilize STMN1/TGFB1 mRNA. Based on these findings, a Trojan horse nanotherapy strategy with co-loading of siRNA against cPKM (si-cPKM) and paclitaxel (PTX) is developed. The siRNA/PTX co-loaded nanosystem (Trojan horse) efficiently penetrates tumor tissues, releases si-cPKM and paclitaxel (soldiers), promotes paclitaxel sensitization, and suppresses ICC proliferation and metastasis in vivo. Furthermore, it alleviates the fibrosis of ICC tumor stroma and reopens collapsed tumor vessels (opening the gates), thus enhancing the efficacy of the standard chemotherapy regimen (main force). This novel nanotherapy provides a promising new strategy for ICC treatment.
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Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Linhagem Celular Tumoral , Colangiocarcinoma/tratamento farmacológico , Colangiocarcinoma/genética , RNA Interferente Pequeno , Paclitaxel/uso terapêutico , Ductos Biliares Intra-Hepáticos/metabolismo , Ductos Biliares Intra-Hepáticos/patologia , Neoplasias dos Ductos Biliares/tratamento farmacológico , Neoplasias dos Ductos Biliares/genética , Fibrose , Microambiente Tumoral , Fator de Crescimento Transformador beta1/metabolismo , Proteínas de Ligação a RNA , Estatmina/metabolismoRESUMO
STUDY DESIGN: A randomized, controlled follow-up study. OBJECTIVE: The objective of this study was to compare the results of anterior approach versus posterior approach with subtotal corpectomy, decompression, and reconstruction of spine in the treatment of thoracolumbar burst fractures. SUMMARY OF BACKGROUND DATA: Burst fractures are frequently associated with instability or neurological deficit. Anterior subtotal corpectomy, decompression, and reconstruction with instrumentation are an established method for a highly unstable burst fracture. In the past few years, subtotal corpectomy, decompression, and reconstruction of spine could be completed by posterior approach. Posterior segmental pedicle screw instrumentation, with its more rigid fixation and less technically demanding, could offer potential advantages. METHODS: A total of 64 patients with thoracolumbar burst fractures were divided into 2 groups randomly. Group A was treated by anterior approach and group B was treated by posterior approach with subtotal corpectomy, decompression, and reconstruction of spine. During the minimum 24 months (range, 24 to 72 mo) follow-up period, all patients were prospectively evaluated for clinical and radiologic outcomes. The intraoperative blood loss, operative time, complications of operation, pulmonary function, Frankel scale, and the American Spinal Injury Association (ASIA) motor score were used for clinical evaluation, whereas the heights of anterior edge of vertebral body and the Cobb angle were examined for radiologic outcome. RESULTS: All patients in this study achieved solid fusion, with significant neurological improvement. The intraoperative blood loss (P<0.05) and complications of operation were less, the operative time was shorter (P<0.05), and the pulmonary function after operation was better in the group B (P<0.05). The Frankel scale, the ASIA motor score, and the radiologic results were not significantly different (P<0.05) at all time points between the 2 groups A and B. But the 2 groups improved in their neurological function by approximately 1.3 Frankel grade and 15.6 ASIA motor scores at final follow-up. CONCLUSION: Anterior approach and posterior approach with subtotal corpectomy, decompression, and reconstruction of spine are sufficient for surgical treatment of thoracolumbar burst fractures. Less intraoperative blood loss and complications, shorter operative time, and better pulmonary function after operation are the significant advantages of posterior surgery.