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In this work, a novel organodiphosphate-containing inorganic-organic hybrid polyoxoniobate (PONb) ring {(PO3CH2CH2PO3H)4Nb8O16}4- (Nb8P8) has been achieved by a one-pot hydrothermal method. The ring is constructed from a tetragonal {Nb8O36} motif and four {PO3CH2CH2PO3H} ligands. Interestingly, Nb8P8 can be joined together via K-H2O clusters {K2(H2O)4(OH)2} to form one-dimensional chains {[K2(H2O)4(OH)2]Nb8P8}n and further linked by {Cu(en)2}2+ (en = ethylenediamine) complexes, resulting in a three-dimensional supramolecular framework {[Cu(en)2]2[K2(H2O)4(OH)2]Nb8P8}·3en·H2O (1). 1 exhibits good chemical and thermal stability and has a high water vapor adsorption capacity of ≤224 cm3 g-1 (22.71 mol·mol-1) at 298 K, outperforming most of the known polyoxometalate-based materials. Impedance measurements prove that 1 can transfer protons with moderate conductivity. This study not only contributes to the structural diversity of organodiphosphate-containing PONbs and PONb rings but also provides a reference for the development of PONb-based materials with unique performance.
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INTRODUCTION: The aim of the study was to conduct a systematic review to explore the therapeutic effect of transcatheter arterial chemoembolization (TACE) combined with portal vein embolization (PVE) for patients with hepatocellular carcinoma (HCC). METHODS: Chinese and English databases (PubMed, Web of Science, Cochrane Library, China National Knowledge Infrastructure, Wanfang database, and VIP database) were searched from database inception to August 15, 2023. Studies comparing TACE combined with PVE versus TACE alone for patients with HCC were included. The degree of heterogeneity was assessed using I2 statistics and a Q test. The effect size was represented by risk ratio and mean difference (MD), and the effect size range was estimated using a 95% confidence interval (CI). RESULTS: Eight eligible studies were included in the systematic review, involving 689 participants. The results showed that the future liver residual (FLR) of patients treated with TACE combined with PVE was significantly higher than that of those treated with PVE alone (MD = 3.99%; 95% CI: 1.03-6.94). Furthermore, compared with PVE alone, TACE combined with PVE had a positive effect on disease-free survival (odds ratio [OR] = 2.16; 95% CI: 1.20-3.88), recurrence rate (OR = 0.79; 95% CI: 0.07-9.42), and complications (OR = 0.53; 95% CI: 0.30-0.96). There was no statistically significant impact on mortality with TACE combined with PVE treatment. CONCLUSION: The combination of TACE with PVE can significantly reduce the FLR of patients with HCC, with higher disease-free survival, lower recurrence rate, and fewer complications.
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Atomically precise low-nuclearity (n<10) silver nanoclusters (AgNCs) have garnered significant interest due to their size-dependent optical properties and diverse applications. However, their synthesis has remained challenging, primarily due to their inherent instability. The present study introduces a new feasible approach for clustering silver ions utilizing highly negative and redox-inert polyoxoniobates (PONbs) as all-inorganic ligands. This strategy not only enables the creation of novel Ag-PONb composite nanoclusters but also facilitates the synthesis of stable low-nuclearity AgNCs. Using this method, we have successfully synthesized a small octanuclear rhombic [Ag8]6+ AgNC stabilized by six highly negative [LiNb27O75]14- polyoxoanions. This marks the first PONb-protected superatomic AgNC, designated as {Ag8@(LiNb27O75)6} (Ag8@Nb162), with an aesthetically spherical core-shell structure. The crystalline Ag8@Nb162 is stable under ambient conditions, What's more, it is water-soluble and able to maintain its molecular cluster structure intact in water. Further, the stable small [Ag8]6+ AgNC has interesting temperature- and pH-dependent reversible fluorescence response, based on which a multiple optical encryption mode for anti-counterfeit technology was demonstrated. This work offers a promising avenue for the synthesis of fascinating and stable PONb-protected AgNCs and sheds light on the development of new-type optical functional materials.
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A unique heteropolyoxotantalate (hetero-POTa) cluster [P2O7Ta5O14]7- (P2Ta5) was first developed using pyrophosphate as a key to open the ultrastable skeleton of the classical Lindqvist-type [Ta6O19]8- precursor. The P2Ta5 cluster can serve as a general and flexible secondary building unit to create a family of brand-new multidimensional POTa architectures. This work not only promotes the limited structural diversity of hetero-POTa but also provides a practical strategy for new extended POTa architectures.
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OBJECTIVE: To construct a predictive model for pain in patients undergoing hepatic arterial chemoembolization (TACE) in interventional operating room. METHODS: Through literature review and expert interviews, a questionnaire was prepared for the assessment of pain factors in patients with hepatic arterial chemoembolization. A prospective cohort study was used to select 228 patients with hepatic arterial chemoembolization in a tertiary and first-class hospital. The data of the patients in the pain group and the non-pain group were compared, and a rapid screening prediction model was constructed by univariate analysis and logistic regression analysis, and its prediction effect was tested. RESULTS: Tumor size, liver cancer stage, and chemoembolization with drug-loaded microspheres and pirarubicin hydrochloride (THP) mixed with lipiodol were independent predictors of pain in patients after hepatic arterial chemoembolization. Finally, the pain prediction model after TACE was obtained. The results of Hosmer-Lemeshow test showed that the model fit was good (χ2 = 13.540, p = 0.095). The area under the receiver operating characteristic curve was 0.798, p < 0.001. CONCLUSION: The rapid screening and prediction model of pain in patients undergoing hepatic arterial chemoembolization has certain efficacy, which is helpful for clinical screening of patients with high risk of pain, and can provide reference for predictive pain management decision-making.
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Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/patologia , Estudos Prospectivos , Quimioembolização Terapêutica/efeitos adversos , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/patologia , Resultado do TratamentoRESUMO
In this paper, a low-temperature thick oil demulsifier with high polarity was prepared by introducing ethylene oxide, propylene oxide block, and butylene oxide using m-diphenol as a starting agent. The main reasons for the difficulty involved in the low-temperature emulsification of extractive fluids were explained by analyzing the synthetic influencing factors and infrared spectra of the star comb polymer (PR-D2) and by analyzing the four fractions, interfacial energies, and zeta potentials of crude oils from the Chun and Gao fields. The effects of PR-D2 surfactant on the emulsification performance of crude oil recovery fluids were investigated via indoor and field experiments. The experimental results indicate that the optimal synthesis conditions for this emulsion breaker are as follows: a quality ratio of ionic reaction intermediates and meso-diphenol of R = 10:1; 1 g of the initiator; a polymerization temperature of 80 °C; and a reaction time of 8 h. Colloidal asphaltenes in the crude oil were the main factor hindering the low-temperature demulsification of the Gao oilfield's extractive fluids, and the reason for the demulsification difficulty of the extractive fluids in the Chun oilfield is that the temperature of demulsification is lower than the wax precipitation point. The demulsification rate of the Chun oilfield's extractive fluids reached more than 98% when the PR-D2 concentration reached 150 mg/L at 43 °C. The demulsification rate of the Gao oilfield's extractive fluids reached more than 98% at a PR-D2 concentration of 150 mg/L at 65 °C. The field experiments show that the Chun oilfield's extractive fluids can still demulsify after the temperature is reduced to 43 °C in winter. The emulsification temperature of the Gao oilfield's extractive fluids was reduced from 73 °C to 68 °C, with an excellent demulsification effect.
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Inspired by the metal-oxo cluster structural feature and charge separation behaviour of the oxygen evolving center (OEC) in photosystem II (PS-II) under photoirradiation, a new crystalline photochromic polyoxomolybdate, MV2 [ß-Mo8 O26 ] (1, MV=methyl viologen cation), is designed as a biomimetic oxygen evolution reaction (OER) catalyst in neutral electrolytes. After photoinduced electron transfer (PIET) with colour change from colourless to grey, it remains in an ultra-stable charge-separated state over a year under ambient conditions. The observed overpotential at 10â mA â cm-2 and Tafel slope decrease by 49â mV and 62.8â mV â dec-1 after coloration, respectively. The outstanding OER performance of the coloured state in neutral electrolytes even outperforms the commercial RuO2 benchmark. Experimental and theoretical studies show that oxygen holes within polyanions after irradiation serve as sites for enhancing direct O-O coupling, thus effectively promoting OER. This is the first successful application of electron-transfer photochromism to realize OER activity gain.
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BACKGROUND: Esophageal squamous cell carcinoma (ESCC) is the leading cause of cancer-related death worldwide with a poor prognosis. Given that DEPDC1B plays a key role in multiple cancers, the role of this molecule in ESCC was explored to identify potential targets for ESCC patients. METHOD: The expression level of DEPDC1B in ESCC was revealed based on the TCGA database and immunohistochemical experiments on clinical tissues. The correlation between DEPDC1B and survival of ESCC patients was analyzed by Kaplan-Meier method. Small hairpin RNA (shRNA)-mediated silencing of DEPDC1B expression in ESCC cells and performed a series of in vitro and in vivo functional validations. RESULT: DEPDC1B was overexpressed in ESCC. High expression of DEPDC1B was significantly negatively correlated with overall survival in patients with ESCC. Moreover, knockdown of DEPDC1B inhibited ESCC cell proliferation, clone formation, migration, tumor formation and promoted apoptosis. Furthermore, knockdown of DEPDC1B leaded to significant downregulation of GABRD in ESCC cells. Meanwhile, GABRD expression was upregulated in ESCC, and its silencing can inhibit the proliferation and migration of the tumor cells. Interestingly, there was a protein interaction between DEPDC1B and GABRD. Functionally, GABRD knockdown partially reversed the contribution of DEPDC1B to ESCC progression. In addition, GABRD regulated ESCC progression may depend on PI3K/AKT/mTOR signaling pathway. CONCLUSION: DEPDC1B collaborated with GABRD to regulate ESCC progression, and inhibition of this signaling axis may be a potential therapeutic target for ESCC.
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BACKGROUND: Lymph node (LN) dissection along left recurrent laryngeal nerve (RLN) is challenging in esophagectomy for esophageal cancer, and double-lumen endotracheal tube (DLT) impedes the exposure of this area. The aim of this study was to determine whether bronchial blockers (BB) could be a better choice for this procedure. METHODS: The clinical characteristics of patients who received McKeown esophagectomy with radical lymph node dissection in Wuhan Tongji Hospital between August 2017 and July 2019 were retrospectively analyzed. The 1:1 propensity score match analysis was performed to compare the short-term effectiveness, the numbers of lymph nodes dissected, and the patterns of recurrence and survival between the two groups. RESULTS: A total of 294 patients (192 and 102 in the DLT and BB group, respectively) were enrolled in the study. After matching, 204 patients (102 pairs) who underwent one-lung ventilation with DLT or BB displayed no significant variance in baseline characteristics. The BB group had higher number of LNs resected along left RLN (1.8 ± 2.3 vs. 2.5 ± 2.5, P = 0.001). For patients with metastatic left RLN LN, the BB group had longer medium survival time (15 vs. 32 months, P = 0.045), and tended to have longer medium recurrence-free survival time (6 vs. 15 months, P = 0.079), and lower rate of upper mediastinal and cervical LN recurrence (30.00% vs. 66.67%, P = 0.198). The postoperative complications were similar in both groups. CONCLUSIONS: Compared with DLT, using BB in esophagectomy may allow more radical lymphadenectomy along left RLN.
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Neoplasias Esofágicas , Nervo Laríngeo Recorrente , Neoplasias Esofágicas/patologia , Neoplasias Esofágicas/cirurgia , Esofagectomia/métodos , Humanos , Excisão de Linfonodo/métodos , Linfonodos/patologia , Nervo Laríngeo Recorrente/cirurgia , Estudos RetrospectivosRESUMO
BACKGROUND: With the growing number of patients with coexisting pulmonary and mediastinal lesions detected, reports about simultaneous video-assisted thoracic surgery (VATS) for these concurrent diseases are still rare. To further explore the safety and effectiveness of simultaneous resection of pulmonary and mediastinal lesions by uniportal or biportal VATS, we retrospectively analyzed the clinical data of the largest series of cases to date. METHODS: From July 2018 to July 2021, all patients whose pulmonary lesions and mediastinal tumors were resected simultaneously in our institution were retrospectively reviewed. Their demographic and clinical data were collected and analyzed. RESULTS: A total of 54 patients were enrolled, of whom 44 underwent unilateral uniportal VATS, 3 underwent bilateral uniportal VATS and 7 underwent unilateral biportal VATS. Seven cases were converted to thoracotomy during surgery. For the remaining 47 patients with various demographic and clinical characteristics, most of the operations were completed within 3 h (n = 33, 70.2%) with blood loss of no more than 100 mL (n = 43, 91.5%). The duration of chest tube drainage was 5.66 ± 3.34 days, and the average daily volume was 196.90 ± 122.31 mL. Four cases of postoperative complications occurred during hospitalization. The length of postoperative hospital stay was 8.60 ± 3.63 days. No severe complications or deaths were observed during follow-up. CONCLUSIONS: Uniportal and biportal VATS are safe and effective for simultaneous resection of selected coexisting pulmonary and mediastinal lesions, but the indications and operational details need more evaluation.
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Neoplasias Pulmonares , Cirurgia Torácica Vídeoassistida , Humanos , Neoplasias Pulmonares/cirurgia , Pneumonectomia , Estudos Retrospectivos , ToracotomiaRESUMO
Quantitative information about protein-ligand interactions is central to drug discovery. To obtain the quintessential reaction dissociation constant, ideally measurements of reactions should be performed without perturbations by molecular labeling or immobilization. The technique of transient induced molecular electrical signal (TIMES) has provided a promising technique to meet such requirements, and its performance in a microfluidic environment further offers the potential for high throughput and reduced consumption of reagents. In this work, we further the development by using integrated TIMES signal (i-TIMES) to greatly enhance the accuracy and reproducibility of the measurement. While the transient response may be of interest, the integrated signal directly measures the total amount of surface charge density resulted from molecules near the surface of electrode. The signals enable quantitative characterization of protein-ligand interactions. We have demonstrated the feasibility of i-TIMES technique using different biomolecules including lysozyme, N,N',Nâ³-triacetylchitotriose (TriNAG), aptamer, p-aminobenzamidine (pABA), bovine pancreatic ribonuclease A (RNaseA), and uridine-3'-phosphate (3'UMP). The results show i-TIMES is a simple and accurate technique that can bring tremendous value to drug discovery and research of intermolecular interactions.
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Ligantes , Microfluídica , Muramidase/metabolismo , Ribonuclease Pancreático/metabolismo , Animais , Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Benzamidinas/química , Benzamidinas/metabolismo , Bovinos , Concentração de Íons de Hidrogênio , Muramidase/química , Ribonuclease Pancreático/química , Uridina Monofosfato/análogos & derivados , Uridina Monofosfato/química , Uridina Monofosfato/metabolismoRESUMO
BACKGROUND/AIMS: KRas is usually mutated in non-small cell lung cancer (NSCLC). The mutated KRas gene is a negative prognostic indicator that promotes tumor proliferation, metastasis, and drug resistance in NSCLC, and thus has become a target for cancer therapy. This study is focused on the effects of the microRNA (miR)-202/KRas axis in regulating chemosensitivity in NSCLC. METHODS: Quantitative reverse transcriptase real-time PCR analysis was performed to examine the expression of miR-202. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assays were performed to evaluate the sensitivity of cisplatin against NSCLC cells. The miR-202/KRas axis was confirmed by western blot and luciferase reporter assays. Cell apoptosis was measured by flow cytometry. KRas expression, MEK1/2 and ERK1/2 phosphorylation, and activation of caspase-9 and caspase-3 were detected by western blot. RESULTS: A significant decrease in miR-202 expression was observed in NSCLC cells both in vivo and in vitro. In addition, miR-202 expression was associated with drug resistance. Recovery of miR-202 expression levels was found to increase the sensitivity of both NCI-H441 and A549 NSCLC cells to cisplatin treatment. Mechanically, as the Ras/mitogen-activated protein kinase (MAPK) pathway was aberrantly activated in NCI-H441 and A549 NSCLC cells, the overexpression of miR-202 was found to inhibit the Ras/MAPK pathway by targeting the KRas gene. As a result, increased miR-202 expression expanded apoptosis signaling induced by cisplatin in NSCLC cells. CONCLUSION: The miR-202/KRas axis controlled the chemosensitivity of NSCLC by mediating the Ras/MAPK pathway. Thus, the combination of platinum-based drugs with miR-202 may represent a novel strategy to enhance the anti-tumor effect against NSCLC.
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Antineoplásicos/farmacologia , Carcinoma Pulmonar de Células não Pequenas/genética , Cisplatino/farmacologia , Neoplasias Pulmonares/genética , MicroRNAs/genética , Proteínas Proto-Oncogênicas p21(ras)/metabolismo , Células A549 , Animais , Antineoplásicos/uso terapêutico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Linhagem Celular Tumoral , Cisplatino/uso terapêutico , Regulação para Baixo/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos Endogâmicos BALB C , Camundongos Nus , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas p21(ras)/genética , Transdução de Sinais/efeitos dos fármacosRESUMO
Tyrosine kinase inhibitors (TKIs) exert potent therapeutic efficacy in non-small cell lung cancers (NSCLC) harboring epidermal growth factor receptor (EGFR) activating mutations. However, a major impediment for the effective treatment is the development of drug resistance. Some evidence supports a role for miRNAs in modulating NSCLC TKIs resistance. Here we show that miR-181a is significantly up-regulated in gefitinib-resistant cells compared with gefitinib-sensitive cells. Upregulation of miR-181a caused resistance of gefitinib, whereas downregulation of miR-181a sensitized NSCLC cells to gefitinib. Furthermore, the miR-181a plasma levels were significantly increased in acquired gefitinib resistant NSCLC patients compared with the plasma levels prior to gefitinib treatment in each patient. Bioinformatics analysis and luciferase reporter assay showed that growth arrest-specific 7 (GAS7) was a direct target gene of miR-181a. A significant inverse correlation between the expression of miR-181a and GAS7 was identified in NSCLC tissues. Downregulation of GAS7 expression could antagonize gefitinib re-sensitivity in PC9GR mediated by knockdown of miR-181a via AKT/ERK pathways and epithelial-to-mesenchymal transition markers. Additionally, GAS7 expression was downregulated in a large cohort of NSCLC patients, and a high mRNA level of GAS7 was associated with improved overall survival. Collectively, our findings provide a novel basis for using miR-181a/GAS7-based therapeutic strategies to reverse gefitinib resistance in NSCLC.
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Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/tratamento farmacológico , Neoplasias Pulmonares/metabolismo , MicroRNAs/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Quinazolinas/uso terapêutico , Biomarcadores Tumorais/metabolismo , China/epidemiologia , Feminino , Gefitinibe , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Inibidores de Proteínas Quinases/toxicidade , Fatores de Risco , Taxa de SobrevidaRESUMO
Glycerol offers several advantages as a substrate for biotechnological applications. An important step toward using the popular production host Saccharomyces cerevisiae for glycerol-based bioprocesses has been the fact that in recent studies commonly used S. cerevisiae strains were engineered to grow in synthetic medium containing glycerol as the sole carbon source. For metabolic engineering projects of S. cerevisiae growing on glycerol, characterized promoters are missing. In the current study, we used transcriptome analysis and a yECitrine-based fluorescence reporter assay to select and characterize 25 useful promoters. The promoters of the genes ALD4 and ADH2 showed 4.2-fold and 3-fold higher activities compared to the well-known strong TEF1 promoter. Moreover, the collection contains promoters with graded activities in synthetic glycerol medium and different degrees of glucose repression. To demonstrate the general applicability of the promoter collection, we successfully used a subset of the characterized promoters with graded activities in order to optimize growth on glycerol in an engineered derivative of CEN.PK, in which glycerol catabolism exclusively occurs via a non-native DHA pathway.
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Glicerol/farmacologia , Engenharia Metabólica/métodos , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Meios de Cultura/química , Perfilação da Expressão Gênica , Redes e Vias MetabólicasRESUMO
To promote the activity and stability of immobilized porcine pancreatic lipase (PPL), novel carrier was combined with special immobilization method. Enzymatic activity was enhanced after immobilized onto ionic liquid modified magnetic Fe3O4 by electrostatic adsorption. Activity of immobilized enzyme (PPL-IM/BF4-Fe3O4@CA) reached 596 U/g PPL. Through the combination of electrostatic adsorption and embedding immobilization methods, we improve binding force between the carrier and enzyme, and further enhance the efficiency and stability of immobilized enzyme. The activity of PPL-IM/BF4-Fe3O4@CA after repeated third use was 78%. After storage at room temperature for 5 days, the residual activity was 89%. Enzymatic properties and catalytic kinetics of immobilized enzymes were studied, and the effect mechanism of ionic liquid modified Fe3O4 on PPL was revealed. The effect of ionic liquid on the carrier structure was investigated by characterization of XRD, FT-IR, SEM and TG. The mechanism and enzymatic properties of immobilized PPL via electrostatic adsorption and embedding were analyzed. A novel and efficient immobilized PPL was developed.
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Enzimas Imobilizadas/química , Óxido Ferroso-Férrico/química , Líquidos Iônicos/química , Lipase/química , Pâncreas/enzimologia , Adsorção , Animais , SuínosRESUMO
BACKGROUND: Chemical peeling is an efficient method for the treatment of pigment disorders. For freckles, medium-depth to deep peeling using a phenol solution is one of the most effective chemical peels, and modifications of facial skin can be observed up to 20 years after peeling. However, applying phenol to the skin may cause serious side effects. Phenol peeling has been rarely used in Asia due to its tendency to cause permanent pigmentary changes and hypertrophic scars. METHODS: In total, 896 Chinese inpatients with facial freckles were enrolled in this study. The phenol formula was modified with crystalline phenol, dyclonine, camphor, anhydrous alcohol and glycerin and adjusted to a concentration of 73.6-90.0%. The entire peeling treatment was divided into two procedures performed separately on 2 days. RESULTS: All patients exhibited 26% or greater improvement, and 99.66% of patients exhibited 51% or greater improvement (good and excellent). Scarring and systemic complications were not observed in any patient. CONCLUSIONS: The modified phenol formula is very effective and safe for the treatment of facial freckles in Asian patients. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .
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Povo Asiático , Abrasão Química/métodos , Melanose/etnologia , Melanose/terapia , Fenóis/farmacologia , Absorção Cutânea/efeitos dos fármacos , Administração Tópica , Adolescente , Adulto , China , Estudos de Coortes , Dermatoses Faciais/terapia , Feminino , Seguimentos , Humanos , Masculino , Segurança do Paciente , Estudos Retrospectivos , Medição de Risco , Resultado do Tratamento , Adulto JovemRESUMO
BACKGROUND: Besides being a major regulator of the response to acetic acid in Saccharomyces cerevisiae, the transcription factor Haa1 is an important determinant of the tolerance to this acid. The engineering of Haa1 either by overexpression or mutagenesis has therefore been considered to be a promising avenue towards the construction of more robust strains with improved acetic acid tolerance. RESULTS: By applying the concept of global transcription machinery engineering to the regulon-specific transcription factor Haa1, a mutant allele containing two point mutations could be selected that resulted in a significantly higher acetic acid tolerance as compared to the wild-type allele. The level of improvement obtained was comparable to the level obtained by overexpression of HAA1, which was achieved by introduction of a second copy of the native HAA1 gene. Dissection of the contribution of the two point mutations to the phenotype showed that the major improvement was caused by an amino acid exchange at position 135 (serine to phenylalanine). In order to further study the mechanisms underlying the tolerance phenotype, Haa1 translocation and transcriptional activation of Haa1 target genes was compared between Haa1 mutant, overproduction and wild-type strains. While the rapid Haa1 translocation from the cytosol to the nucleus in response to acetic acid was not affected in the Haa1S135F mutant strain, the levels of transcriptional activation of four selected Haa1-target genes by acetic acid were significantly higher in cells of the mutant strain as compared to cells of the wild-type strain. Interestingly, the time-course of transcriptional activation in response to acetic acid was comparable for the mutant and wild-type strain whereas the maximum mRNA levels obtained correlate with each strain's tolerance level. CONCLUSION: Our data confirms that engineering of the regulon-specific transcription factor Haa1 allows the improvement of acetic acid tolerance in S. cerevisiae. It was also shown that the beneficial S135F mutation identified in the current work did not lead to an increase of HAA1 transcript level, suggesting that an altered protein structure of the Haa1S135F mutant protein led to an increased recruitment of the transcription machinery to Haa1 target genes.
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Ácido Acético/farmacologia , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/fisiologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Expressão Gênica , Mutação Puntual , Regiões Promotoras Genéticas , Saccharomyces cerevisiae/efeitos dos fármacos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/biossíntese , Fatores de Transcrição/biossínteseRESUMO
Emerging evidence suggests toll-like receptor 4 (TLR4) signaling contributes to cancer development and progression. However, the consequences of signaling via the TLR4 pathway in esophageal squamous cell carcinoma (ESCC) are still unclear. Here, we investigated the impact of Lipopolysaccharide (LPS)-induced TLR4 signaling on ESCC cell proliferation, inflammatory cytokines expression, and downstream molecular mechanisms. Seventy-eight ESCC and 26 normal esophageal specimens were analyzed by immunohistochemistry, and two cell lines (Eca-109 and TE-1) were used for in vitro studies. LPS, a natural agonist of TLR4, was used to activate TLR4 signaling. The effects of LPS-TLR4 signaling on cell proliferation and inflammatory cytokines regulation were examined. Specific inhibitors of mitogen-activated protein kinase (MAPK) (extracellular regulated protein kinase [ERK] and p38) signaling pathways were used to investigate the role of each pathway in LPS-TLR4 signaling. TLR4 protein was increased in ESCC tumor tissues compared with the adjacent normal tissues. TLR4 over-expression was significantly correlated with tumor differentiation grade, lymph node metastasis, and UICC stage. LPS-induced activation of TLR4 signaling promoted cancer cell proliferation, increased production of proinflammatory or immunosuppressive cytokines TNF-α, TGF-ß and inhibited the anti-inflammatory cytokine IL-10. LPS-TLR4 signaling was associated with the activation of ERK and p38 MAPK signaling pathways. Further inactivation of the two pathways by specific inhibitors attenuated cell proliferation and inflammatory cytokines expression induced by LPS. Our results indicate that LPS-TLR4 signaling in cancer cells contributes to the progression of human ESCC.
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Carcinoma de Células Escamosas/metabolismo , Proliferação de Células/efeitos dos fármacos , Citocinas/metabolismo , Neoplasias Esofágicas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor 4 Toll-Like/fisiologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Carcinoma de Células Escamosas do Esôfago , Feminino , Humanos , Lipopolissacarídeos , Masculino , Pessoa de Meia-Idade , Receptor 4 Toll-Like/efeitos dos fármacosRESUMO
The yeast Saccharomyces cerevisiae generally shows a low natural capability to utilize glycerol as the sole source of carbon, particularly when synthetic medium is used and complex supplements are omitted. Nevertheless, wild type isolates have been identified that show a moderate growth under these conditions. In the current study we made use of intraspecies diversity to identify targets suitable for reverse metabolic engineering of the non-growing laboratory strain CEN.PK113-1A. A genome-wide genetic mapping experiment using pooled-segregant whole-genome sequence analysis was conducted, and one major and several minor genetic loci were identified responsible for the superior glycerol growth phenotype of the previously selected S. cerevisiae strain CBS 6412-13A. Downscaling of the major locus by fine-mapping and reciprocal hemizygosity analysis allowed the parallel identification of two superior alleles (UBR2CBS 6412-13A and SSK1CBS 6412-13A). These alleles together with the previously identified GUT1CBS 6412-13A allele were used to replace the corresponding alleles in the strain CEN.PK113-1A. In this way, glycerol growth could be established reaching a maximum specific growth rate of 0.08h(-1). Further improvement to a maximum specific growth rate of 0.11h(-1) could be achieved by heterologous expression of the glycerol facilitator FPS1 from Cyberlindnera jadinii.
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Mapeamento Cromossômico/métodos , Melhoramento Genético/métodos , Genoma Bacteriano/genética , Glicerol/metabolismo , Engenharia Metabólica/métodos , Proteínas de Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/genética , Vias Biossintéticas/genética , Regulação Bacteriana da Expressão Gênica/genética , Glicerol/isolamento & purificação , Análise do Fluxo Metabólico/métodos , Redes e Vias Metabólicas/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismoRESUMO
A cylindrical lens telescope tilted-pulse-front pumping scheme was proposed for high energy terahertz (THz) pulse generation. This scheme allows higher pump energy to be used with lower saturation effects under high pump fluence, and higher THz generation efficiency was achieved within large range of pump energy. The optimum pump pulse duration and crystal cooling temperature for THz generation in LiNbO3 (LN) crystal were also researched systematically. Excited by 800-nm laser, up to 0.19 mJ THz pulse energy and 0.27% conversion efficiency was demonstrated under 800-nm 400-fs laser excitation with ~100-mJ pulse energy and 150-K LN cooling temperature.