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1.
J Environ Manage ; 301: 113921, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34731946

RESUMO

Biochar has been widely applied as an adsorbent, whose electrochemical capacity and heavy metal adsorption performance can be improved by nitrogen doping. In this work, nitrogen-doped biochar (NBC) was synthesized by calcinating sodium humate with sodium bicarbonate (NaHCO3) and urea as the activation agent and nitrogen source, respectively. The NBC was then used to electrochemically adsorb Cd(II) and As(III,V) from simulated and actual wastewaters, respectively. The results indicated that NaHCO3 activation and nitrogen doping could increase the surface area and nitrogen content of the biochar, contributing to the enhancement of adsorption performance for Cd(II) and As(III,V). The electrosorption capacities for Cd(II) and total arsenic (As(T)) increased first and then reached equilibrium with increasing nitrogen content, increased first and then decreased with increasing calcination temperature, and consistently increased with increasing voltage. The Cd(II) electrosorption capacity (79.0 mg g-1) and As(T) removal ratio (94.0%) at 1.2 V in actual As-contaminated wastewater (1.16 mg L-1) were about 4 and 2.6 folds of their inorganic adsorption capacities, respectively. After five cycles of reuse, the Cd(II) and As(T) removal ratio could be maintained at 65.8% and 51.7% of the initial electrosorption capacity. This work expands the application of NBC for heavy metal removal.


Assuntos
Arsênio , Poluentes Químicos da Água , Adsorção , Cádmio , Carvão Vegetal , Nitrogênio , Águas Residuárias
2.
Biology (Basel) ; 10(11)2021 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-34827136

RESUMO

Carboxypeptidase A4 (CPA4) has shown the potential to be a biomarker in the early diagnosis of certain cancers. However, no previous research has linked CPA4 to therapeutic or prognostic significance in bladder cancer. Using data from The Cancer Genome Atlas (TCGA) database, we set out to determine the full extent of the link between CPA4 and BLCA. We further analyzed the interacting proteins of CPA4 and infiltrated immune cells via the TIMER2, STRING, and GEPIA2 databases. The expression of CPA4 in tumor and normal tissues was compared using the TCGA + GETx database. The connection between CPA4 expression and clinicopathologic characteristics and overall survival (OS) was investigated using multivariate methods and Kaplan-Meier survival curves. The potential functions and pathways were investigated via gene set enrichment analysis. Furthermore, we analyze the associations between CPA4 expression and infiltrated immune cells with their respective gene marker sets using the ssGSEA, TIMER2, and GEPIA2 databases. Compared with matching normal tissues, human CPA4 was found to be substantially expressed. We confirmed that the overexpression of CPA4 is linked with shorter OS, DSF(Disease-specific survival), PFI(Progression-free interval), and increased diagnostic potential using Kaplan-Meier and ROC analysis. The expression of CPA4 is related to T-bet, IL12RB2, CTLA4, and LAG3, among which T-bet and IL12RB2 are Th1 marker genes while CTLA4 and LAG3 are related to T cell exhaustion, which may be used to guide the application of checkpoint blockade and the adoption of T cell transfer therapy.

3.
Biomed Opt Express ; 12(9): 5614-5628, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34692204

RESUMO

Expansion microscopy enables conventional diffraction limit microscopy to achieve super-resolution imaging. However, the enlarged tissue lacks an objective lens with sufficient working distance that can image tissues with whole-brain-scale coverage. Here, we present expansion tomography (ExT) to solve this problem. We have established a modified super-absorbent hydrogel (ExT gel) that possesses high mechanical strength and enables serial sectioning. ExT gel enables tissue and cell imaging and is compatible with various fluorescent labeling strategies. Combining with the high-throughput light-sheet tomography (HLTP) system, we have shown the capability of large volume imaging with nanoscale resolution of mouse brain intact neuronal circuits. The ExT method would allow image samples to support super-resolution imaging of intact tissues with virtually unlimited axial extensions.

4.
J Transl Med ; 19(1): 417, 2021 10 09.
Artigo em Inglês | MEDLINE | ID: mdl-34627268

RESUMO

Clear cell renal cell carcinoma (ccRCC) is the most common malignant tumor of the kidney. New and reliable biomarkers are in urgent need for ccRCC diagnosis and prognosis. The CENP family is overexpressed in many types of cancers, but its functions in ccRCC have not been fully clarified. In this paper, we found that several CENP family members were highly expressed in ccRCC tissues. Also, CENPA expression level was related to clinicopathological grade and prognosis by weighted gene co-expression network analysis (WGCNA). CENPA served as a representative CENP family member as a ccRCC biomarker. Further in vitro experiments verified that overexpression of CENPA promoted ccRCC proliferation and metastasis by accelerating the cell cycle and activating the Wnt/ß-catenin signaling pathway. The elevated ß-catenin led by CENPA overexpression translocated to nucleus for downstream effect. Functional recovery experiment confirmed that Wnt/ß-catenin pathway was essential for ccRCC progression and metastasis. Developing selective drugs targeting CENPA may be a promising direction for cancer treatment.


Assuntos
Carcinoma de Células Renais , Neoplasias Renais , Carcinoma de Células Renais/genética , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Renais/genética , Prognóstico , Via de Sinalização Wnt
5.
Ann Transl Med ; 9(15): 1252, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34532389

RESUMO

Background: Hormone receptor-negative breast cancer (HRNBC), which includes triple-negative breast cancer (TNBC) and human epidermal growth factor receptor 2 (HER-2) overexpressing breast cancer, is prone to metastasis and has a poor prognosis. BTB/POZ domain-containing protein 7 (Btbd7) is thought to regulate SLUG and the epithelial-mesenchymal transition (EMT) process. However, the role of Btbd7 in HRNBC is unclear. Methods: Expression of BTBD7 and SLUG in HRNBC tumor tissue and normal adjacent tissue (NAT) as well as breast cancer cells were characterized by immunohistochemistry and immunofluorescence. MDA-MA-231 cells was transfected with BTBD7 siRNA and detected by qRT-PCR and western blot. Expression levels of Slug and EMT related proteins were detected western blot analysis. cell invasion assays were used to analyse cell invasion ability of MDA-MA-231. GO and KEGG analyses was used to analysis the gene function. Results: The total positive rate of BTBD7 expression in HRNBC tumor tissue was 66.7%, which was higher than that in NAT (52.1%) and benign breast lesion tissues (20%). Co-expression of SLUG and BTBD7 proteins could be found in HRNBC tissue and MDA-MA-231 cells. BTBD7 silencing significantly up-regulated the epithelial marker E-cadherin, down-regulated the mesenchymal markers α-SMA and SLUG and suppressed the invasion abilities of MDA-MA-231 cells. GO and KEGG analyses based on 322 DEGs showed that BTBD7 may be associated with generic transcription in breast cancer. Conclusions: The study data indicated that BTBD7 was inversely associated with SLUG expression. Higher BTBD7 was associated with poor clinicopathologic features and prognosis in HRNBC patients. BTBD7 silencing inhibited EMT through regulation of SLUG expression. BTBD7 might act as a potential molecular target for gene therapy in HRNBC patients.

6.
J Hazard Mater ; 416: 125924, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492856

RESUMO

The chitosan-stabilized biochar supported S-nZVI (CS@BC/S-nZVI) composite with low aggregation and superior antioxidation were successfully synthesized by liquid-phase reduction method for the outstanding removal of Cr(VI) from wastewater and characterized by SEM, BET, FTIR, XRD, and XPS. The optimized synthesis parameters of CS@BC/S-nZVI were determined as a 0.14 molar ratio of S/Fe and a 0.25 mass ratio of BC/Fe. The CS@BC/S-nZVI possessed a specific surface area of 199.246 m2/g and an average pore size and pore volume of 1.186 nm and 0.272 cc/g. The CS@BC/S-nZVI could remain reductive activity after Cr(VI) removal and present a remarkable tolerance to the coexisting ions during Cr(VI) removal. The adsorption data were fitted well by the pseudo-second order model and the Langmuir model. The removal of Cr(VI) by CS@BC/S-nZVI was an exothermic process with prominent Cr(VI) removal capacities of 244.07 mg/g at 120 min and 221.84 mg/g at 15 min at 25 â„ƒ. Further mechanism analysis proved that the binding of Cr(VI) to CS@BC/S-nZVI was mainly a synergistic effect of reduction and electrostatic attraction. Overall, these findings shed new light on the research of a novel S-nZVI compound and revealed the potential practical application of CS@BC/S-nZVI in the future heavy metal removal from wastewater.


Assuntos
Ferro , Poluentes Químicos da Água , Adsorção , Cromo , Poluentes Químicos da Água/análise
7.
J Diabetes Res ; 2021: 7945117, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34568499

RESUMO

Objectives: Diabetic wound inflammation deficiencies lead to ulcer development and eventual amputation and disability. Our previous research demonstrates that myeloid-derived suppressor cells (MDSCs) accumulate during inflammation and promote chronic wound healing via the regulation of Kruppel-like factor 4 (KLF4). In this study, we aimed to investigate the potential roles of MDSCs and KLF4 in diabetic wound healing. Methods: An ob/ob mouse pressure ulcer (PU) model was used to evaluate the process of wound healing. The expression levels of KLF4 and IL-17A were measured by real-time PCR, and the population of MDSCs and Th17 cells was measured by flow cytometry. The levels of cytokines were determined by an immunosuppression assay. Results: KLF4 deficiency in the diabetic PU model resulted in decreased accumulation of MDSCs, increased expansion of Th17 cells, and significantly delayed wound healing. Conversely, KLF4 activation by APTO-253 accelerated wound healing accompanied by increased MDSC populations and decreased numbers of Th17 cells. MDSCs have been proven to mediate Th17 differentiation via cytokines, and our in vitro data showed that elevated KLF4 expression in MDSCs resulted in reduced Th17 cell numbers and, thus, decreased levels of cytokines indispensable for Th17 differentiation. Conclusions: Our study revealed a previously unreported function of KLF4-regulated MDSCs in diabetic wound healing and identified APTO-253 as a potential agent to improve the healing of pressure ulcers.

8.
J Endourol ; 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34569266

RESUMO

OBJECTIVES: Compare color Doppler (Color) ultrasound-guided puncture to common type-B (Type-B) ultrasound-guided puncture in reducing the incidence of hemorrhagic complications of percutaneous nephrolithotomy (PCNL). MATERIALS AND METHODS: A total of 348 patients who received PCNL from September 2017 to December 2018 were divided into Color (231 cases) and Type-B groups (117 cases). The avascular area of the target fornix was pinpointed in the Color group while the middle of the target fornix was the default puncture point in the Type-B group. Tract bleeding, nephrostomy tract creation time, operation time, postoperative hemoglobin (Hb) values and serum creatinine (Scr) concentrations, and stone-free rates were analyzed. RESULTS: Color Doppler imaging revealed that 35.1% of the cases in the Color group (81/231) had variable artery positioning in the target fornix. Tract bleeding and postoperative Hb reduction in the Color group were significantly lower than the Type-B group (10.8% vs 24.8%, P=0.0007, and 4.87±8.58 vs 7.70±8.90 g/L, P=0.0044, respectively). The postoperative hospitalization of the Color group was also shortened (8.3±5.9 vs 9.7±3.0 d, P<0.0001). Although working channel creation took longer in this group (4.2±0.3 vs 3.6±0.2 min, P<0.0001), there were no significant differences in the total operation time between the two groups (39.2±15.2 vs 36.4±16.5 min, P=0.1097) or postoperative Scr and stone-free rates. CONCLUSION: Vascular variation of the fornix is very common. Consistent puncture of the avascular area of the target fornix significantly lowered tract bleeding and postoperative Hb decrease compared to traditional procedures. Color Doppler ultrasound-guided puncture is thus useful to reduce the incidence of severe hemorrhagic complications of PCNL.

9.
BMC Cancer ; 21(1): 986, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-34479488

RESUMO

BACKGROUND: Prosthesis-related complications, after knee reconstruction with endoprosthesis during operation for tumors around the knee, remain an unresolved problem which necessitate a revision or even an amputational surgery. The purpose of the current study was to identify significant risk factors associated with implant failure, and establish a novel model to predict survival of the prosthesis in patients operated with endoprostheses for tumor around knee. METHODS: We retrospectively reviewed the clinical database of our institution for patients who underwent knee reconstruction due to tumors. A total of 203 patients were included, including 123 males (60.6%) and 80 (39.4%) females, ranging in age from 14 to 77 years (mean: 34.3 ± 17.3 years). The cohort was randomly divided into training (n = 156) and validation (n = 47) samples. Univariable COX analysis was used for initially identifying potential independent predictors of prosthesis survival with the training group (p < 0.150). Multivariate COX proportional hazard model was selected to identify final significant prognostic factors. Using these significant predictors, a graphic nomogram, and an online dynamic nomogram were generated for predicting the prosthetic survival. C-index and calibration curve were used for evaluate the discrimination ability and accuracy of the novel model, both in the training and validation groups. RESULTS: The 1-, 5-, and 10-year prosthetic survival rates were 94.0, 90.8, and 83.0% in training sample, and 96.7, 85.8, and 76.9% in validation sample, respectively. Anatomic sites, length of resection and length of prosthetic stem were independently associated with the prosthetic failure according to multivariate COX regression model (p<0.05). Using these three significant predictors, a graphical nomogram and an online dynamic nomogram model were generated. The C-indexes in training and validation groups were 0.717 and 0.726 respectively, demonstrating favourable discrimination ability of the novel model. And the calibration curve at each time point showed favorable consistency between the predicted and actual survival rates in training and validation samples. CONCLUSIONS: The length of resection, anatomical location of tumor, and length of prosthetic stem were significantly associated with prosthetic survival in patients operated for tumor around knee. A user-friendly novel online model model, with favorable discrimination ability and accuracy, was generated to help surgeons predict the survival of the prosthesis.


Assuntos
Prótese do Joelho/estatística & dados numéricos , Neoplasias/cirurgia , Nomogramas , Próteses e Implantes/estatística & dados numéricos , Falha de Prótese/tendências , Procedimentos Cirúrgicos Reconstrutivos/métodos , Adolescente , Adulto , Idoso , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Adulto Jovem
10.
Mol Ecol Resour ; 2021 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-34549890

RESUMO

Populus has a wide ecogeographical range spanning the Northern Hemisphere, and interspecific hybrids are common. Populus tomentosa Carr. is widely distributed and cultivated in the eastern region of Asia, where it plays multiple important roles in forestry, agriculture, conservation, and urban horticulture. Reference genomes are available for several Populus species, however, our goals were to produce a very high quality de novo chromosome-level genome assembly in P. tomentosa genome that could serve as a reference for evolutionary and ecological studies of hybrid speciation throughout the genus. Here, combining long-read sequencing and Hi-C scaffolding, we present a high-quality, haplotype-resolved genome assembly. The genome size was 740.2 Mb, with a contig N50 size of 5.47 Mb and a scaffold N50 size of 46.68 Mb, consisting of 38 chromosomes, as expected with the known diploid chromosome number (2n = 2x = 38). A total of 59,124 protein-coding genes were identified. Phylogenomic analyses revealed that P. tomentosa is comprised of two distinct subgenomes, which we deomonstrate is likely to have resulted from hybridization between Populus adenopoda as the female parent and Populus alba var. pyramidalis as the male parent, with an origin of approximately 3.93 Ma. Although highly colinear, significant structural variation was found between the two subgenomes. Our study provides a valuable resource for ecological genetics and forest biotechnology.

11.
J Hazard Mater ; 419: 126464, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-34323733

RESUMO

Cd pollution in arable soils has posed serious threats to food safety and human health. Mn oxides and Mn oxide-based materials have been widely applied to the removal of heavy metals for their high adsorption capacity, especially in water treatment. However, the performance and stability of Mn oxide-based materials and the underlying mechanism of Cd immobilization in upland soils remain unclear. Here, zeolite-supported Mn oxides were used as amendment to investigate their impact on the availability of soil Cd in wheat pot experiments. The decrease in soil available Cd content (by 44.3%) and increase in soil available Mn content (by 61.9%) significantly inhibited Cd accumulation in wheat plant tissues under the application of zeolite-supported Mn oxides. The exchangeable Cd was transformed to more stable fractionation of Fe-Mn oxide bound Cd, and the maximum decrease of Cd content in wheat grains, straw and roots reached 65.0%, 11.7% and 55.3%, respectively. Besides, zeolite-supported Mn oxides exhibited high chemical stability and stable Cd immobilization performance in two successive years of wheat pot experiments. These findings improve our understanding of Mn oxide-based materials for soil remediation and indicate that zeolite-supported Mn oxides have great potential for the remediation of Cd-contaminated alkaline upland soils.


Assuntos
Poluentes do Solo , Zeolitas , Cádmio/análise , Humanos , Manganês , Óxidos , Solo , Poluentes do Solo/análise , Triticum
12.
Int J Biol Macromol ; 187: 9-23, 2021 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-34298047

RESUMO

Trehalose plays an important role in plant metabolism, growth development, and stress tolerance. Trehalose-6-phosphate synthase gene (TPS) and trehalose-6-phosphate phosphatase gene (TPP) are vital for the synthesis of trehalose. Populus is a prominent perennial woody plant, in which systematic genome-wide analysis of the TPS and TPP family is limited. In this study, 13 PtTPS and 10 PtTPP genes were identified in the Populus genome. Phylogenetic analysis indicated PtTPS and PtTPP genes were both divided into two subfamilies, and gene members of each subfamily have highly conserved intron structures. Analysis of cis-acting elements showed that PtTPS and PtTPP genes were involved in plant hormones and environmental stress responses. Expression profiles also found PtTPSs and PtTPPs expressed differently in response to salt stress, cold, mechanical damage, salicylic acid, and methyl jasmonate treatment. Furthermore, reverse transcription quantitative real-time PCR results found PtTPSs and PtTPPs displayed a specific expression pattern in the seven developmental stages of Populus male and female floral buds. This work will not only lead a foundation on reveal the functions of PtTPS and PtTPP gene families in trehalose regulation of poplar but also provide references to related trehalose research in other perennial plants.

13.
Front Oncol ; 11: 629823, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249679

RESUMO

Introduction: Venous thromboembolism can be divided into deep vein thrombosis and pulmonary embolism. These diseases are a major factor affecting the clinical prognosis of patients and can lead to the death of these patients. Unfortunately, the literature on the risk factors of venous thromboembolism after surgery for spine metastatic bone lesions are rare, and no predictive model has been established. Methods: We retrospectively analyzed 411 cancer patients who underwent metastatic spinal tumor surgery at our institution between 2009 and 2019. The outcome variable of the current study is venous thromboembolism that occurred within 90 days of surgery. In order to identify the risk factors for venous thromboembolism, a univariate logistic regression analysis was performed first, and then variables significant at the P value less than 0.2 were included in a multivariate logistic regression analysis. Finally, a nomogram model was established using the independent risk factors. Results: In the multivariate logistic regression model, four independent risk factors for venous thromboembolism were further screened out, including preoperative Frankel score (OR=2.68, 95% CI 1.78-4.04, P=0.001), blood transfusion (OR=3.11, 95% CI 1.61-6.02, P=0.041), Charlson comorbidity index (OR=2.01, 95% CI 1.27-3.17, P=0.013; OR=2.29, 95% CI 1.25-4.20, P=0.017), and operative time (OR=1.36, 95% CI 1.14-1.63, P=0.001). On the basis of the four independent influencing factors screened out by multivariate logistic regression model, a nomogram prediction model was established. Both training sample and validation sample showed that the predicted probability of the nomogram had a strong correlation with the actual situation. Conclusion: The prediction model for postoperative VTE developed by our team provides clinicians with a simple method that can be used to calculate the VTE risk of patients at the bedside, and can help clinicians make evidence-based judgments on when to use intervention measures. In clinical practice, the simplicity of this predictive model has great practical value.

14.
Front Oncol ; 11: 659208, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34249694

RESUMO

Clear cell renal cell carcinoma (ccRCC) accounts for approximately 4/5 of all kidney cancers. Accumulation of minor changes in the cellular homeostasis may be one cause of ccRCC. Therefore, we downloaded the RNA sequencing and survival data of the kidney renal cell carcinoma (KIRC) cohort from the Cancer Genome Atlas (TCGA) database. After the univariate and multivariate Cox regression analyses, 19 kidney-specific differentially expressed genes (DEGs) were found. Solute Carrier Family 22 Member 12 (SLC22A12) resulted in an independent prognostic predictor for both overall survival (OS) and disease-free survival (DFS). SLC22A12 expression was lower in tumoral tissue compared to normal tissue. Moreover, patients in the SLC22A12 low expression group had a higher pathological stage and worse survival than the high expression group. Additionally, qRT-PCR assay, immunoblotting test (IBT), and immunohistochemical (IHC) analyses of cancer tissues/cells and the corresponding normal controls verified that SLC22A12 is downregulated in ccRCC. Receiver operator characteristic (ROC) curves showed that the low expression level of SLC22A12 could be a good diagnostic marker for ccRCC (AUC=0.7258; p <0.0001). Gene set enrichment analysis (GSEA) showed that SLC22A12 expression levels are related to metabolism, cell cycle, and tumor-related signaling pathways. GO and KEGG analyses revealed that SLC22A12 transports multiple organic compounds, ions, and hormones and participates in the extracellular structure organization. Furthermore, SLC22A12 over-expression in vitro inhibited the proliferation, migration, and invasion of renal cancer cells by regulating PI3K/Akt pathways. Such effects were reversed when knocking out SLC22A12. In summary, as a transporter for many vital metabolites, SLC22A12 may affect tumor cell survival through its impacts on the mentioned metabolites. In conclusion, this study uncovered that SLC22A12 is a promising prognostic and diagnostic biomarker for ccRCC.

15.
Front Neurosci ; 15: 675430, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34220431

RESUMO

Chronic stress is an essential factor leading to depression. However, there exist individual differences in people exposed to the same stressful stimuli. Some people display negative psychology and behavior, while others are normal. Given the importance of individual difference, finding differentially expressed proteins in stress-resistant and stress-susceptible groups has great significance for the study of pathogenesis and treatment of depression. In this study, stress-susceptible rats and stress-resilient rats were first distinguished by sucrose preference test. These stress-susceptible rats also displayed depression-like behaviors in forced swimming test and open field test. Then, we employed label-free quantitative proteomics to analyze proteins in the ventral hippocampus. There were 4,848 proteins totally identified. Based on statistical analysis, we found 276 differentially expressed proteins. Bioinformatics analysis revealed that the biological processes of these differential proteins were related to mitochondrion organization, protein localization, coenzyme metabolic process, cerebral cortex tangential migration, vesicle-mediated transport, and so on. The KEGG pathways were mainly involved in metabolic pathways, axon guidance, autophagy, and tight junction. Furthermore, we ultimately found 20 stress-susceptible proteins and two stress-resilient proteins. These stress-related proteins could not only be potential biomarkers for depression diagnosis but also contribute to finding new therapeutic targets and providing personalized medicine.

16.
Nano Lett ; 21(18): 7870-7878, 2021 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-34318680

RESUMO

Fractal Pt-based materials with hierarchical structures and high self-similarity have attracted more and more attention due to their bioinspiring maximum optimization of energy utilization and mass transfer. However, their high-efficiency design of the mass- and electron-transfer still remains to be a great challenge. Herein, fractal PtPdCu hollow sponges (denoted as PtPdCu-HS) facilitating both directed mass- and electron-transfer are presented. Such directed transfer effects greatly promote electrocatalytic activity, regarded as 3.9 times the mass activity, 7.3 times the specific activity, higher poison tolerance, and higher stability than commercial Pt/C for the methanol oxidation reaction (MOR). A new "directed mass- and electron-transfer" concept, characteristics, and mechanism are proposed at the micro/nanoscale to clarify the structural design and functional enhancement of fractal electrocatalyst. This work displays new possibilities for designing novel nanomaterials with high activity and superior stability toward electrocatalysis or other practical applications.


Assuntos
Elétrons , Fractais , Catálise , Transporte de Elétrons , Oxirredução
17.
Clin Transl Med ; 11(6): e449, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34185414

RESUMO

BACKGROUND: Androgen deprivation therapy (ADT) is the main clinical treatment for patients with advanced prostate cancer (PCa). However, PCa eventually progresses to castration-resistant prostate cancer (CRPC), largely because of androgen receptor variation and increased intratumoral androgen synthesis. Several studies have reported that one abnormal lipid accumulation is significantly related to the development of PCa. Melatonin (MLT) is a functionally pleiotropic indoleamine molecule and a key regulator of energy metabolism. The aim of our study is finding the links between CRPC and MLT and providing the basis for MLT treatment for CRPC. METHODS: We used animal CRPC models with a circadian rhythm disorder, and PCa cell lines to assess the role of melatonin in PCa. RESULTS: We demonstrated that MLT treatment inhibited tumor growth and reversed enzalutamide resistance in animal CRPC models with a circadian rhythm disorder. A systematic review and meta-analysis demonstrated that MLT is positively associated with an increased risk of developing advanced PCa. Restoration of carboxylesterase 1 (CES1) expression by MLT treatment significantly reduced lipid droplet (LD) accumulation, thereby inducing apoptosis by increasing endoplasmic reticulum stress, reducing de novo intratumoral androgen synthesis, repressing CRPC progression and reversing the resistance to new endocrine therapy. Mechanistic investigations demonstrated that MLT regulates the epigenetic modification of CES1. Ces1-knockout (Ces-/- ) mice verified the important role of endogenous Ces1 in PCa. CONCLUSIONS: Our findings provide novel preclinical and clinical information about the role of melatonin in advanced PCa and characterize the importance of enzalutamide combined with MLT administration as a therapy for advanced PCa.

18.
Transl Androl Urol ; 10(5): 2133-2139, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-34159094

RESUMO

The aim of the present study was to report the initial clinical experience of robot-assisted laparoscopic retroperitoneal leiomyosarcoma resection with inferior vena cava graft replacement. The patient was a 45-year-old female with abdominal pain. She was referred to our hospital and found to be with a retroperitoneal mass (46 mm × 45 mm). The inferior vena cava and the distal part of left renal vein were invaded by the tumor and compression was obviously seen from magnetic resonance imaging. The serum level of potassium, epinephrine, norepinephrine, cortisol, adrenocorticotropic hormone and renin angiotensin aldosterone system were all in normal ranges before the surgery. The operation was performed via a six port, robot assisted, transperitoneal laparoscopic approach. The tumor was completely resected and adherent part of inferior vena cava (approximately 5 cm) was dissected. Considering severe impairment of the great vessel, we decided to replace excised caval segment with an extended polytetrafluoroethylene graft and undertook the inferior vena cava reconstruction. The patient was discharged 11 days postoperatively with embolus in the graft. Anticoagulants were routinely administrated and the thrombus seemed to be smaller 3 months after operation. Abdominal pain was resolved and pathological examination finally confirmed that the tumor was leiomyosarcoma with negative margins free from tumor. Leiomyosarcoma of inferior vena cava present a technical challenge to surgeons. Comprehensive preparation should be made preoperatively to facilitate tumor resection and vascular management. In specific cases, robotic resection of leiomyosarcoma from great vessels and vascular repairment might be feasible options in experienced hands.

19.
IEEE Trans Cybern ; PP2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34191739

RESUMO

We consider the decentralized control problem of a class of continuous-time nonlinear systems with mismatched interconnections. Initially, with the discounted cost functions being introduced to auxiliary subsystems, we have the decentralized control problem converted into a set of optimal control problems. To derive solutions to these optimal control problems, we first present the related Hamilton-Jacobi-Bellman equations (HJBEs). Then, we develop a novel critic learning method to solve these HJBEs. To implement the newly developed critic learning approach, we only use critic neural networks (NNs) and tune their weight vectors via the combination of a modified gradient descent method and concurrent learning. By using the present critic learning method, we not only remove the restriction of initial admissible control but also relax the persistence-of-excitation condition. After that, we employ Lyapunov's direct method to demonstrate that the critic NNs' weight estimation error and the states of closed-loop auxiliary systems are stable in the sense of uniform ultimate boundedness. Finally, we separately provide a nonlinear-interconnected plant and an unstable interconnected power system to validate the present critic learning approach.

20.
Proc Natl Acad Sci U S A ; 118(23)2021 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-34088836

RESUMO

We disclose a peculiar rotational propulsion mechanism of Ray sperms enabled by its unusual heterogeneous dual helixes with a rigid spiral head and a soft tail, named Heterogeneous Dual Helixes (HDH) model for short. Different from the conventional beating propulsion of sperm, the propulsion of Ray sperms is from both the rotational motion of the soft helical tail and the rigid spiral head. Such heterogeneous dual helical propulsion style provides the Ray sperm with high adaptability in viscous solutions along with advantages in linearity, straightness, and bidirectional motion. This HDH model is further corroborated by a miniature swimming robot actuated via a rigid spiral head and a soft tail, which demonstrates similar superiorities over conventional ones in terms of adaptability and efficiency under the same power input. Such findings expand our knowledge on microorganisms' motion, motivate further studies on natural fertilization, and inspire engineering designs.

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