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1.
Chemosphere ; 239: 124702, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31520979

RESUMO

Restoration of submerged macrophytes is widely applied to counteract eutrophication in shallow lakes. However, proliferation and accumulation of filamentous algae (possessing free-floating and periphytic life forms) hamper growth of submerged macrophytes. Here, we explored factors triggering the excessive proliferation of filamentous algae during lake restoration using field investigations and laboratory experiments. Results showed that, compared with free-floating Oscillatoria sp. (FO), periphytic Oscillatoria sp. (PO) showed faster growth rate, greater photosynthetic capacities and higher phosphorus (P) affinity. Therefore, PO was physiologically competitively superior to FO under low P concentration and improved light conditions. And proliferation of filamentous algae was mainly manifested in periphytic life form. Besides, field results showed that density of filamentous algae in water column might be related to substrate types. Some macrophyte (Ceratophyllum oryzetorum and Potamogeton crispus) might provide proper substrates for proliferation of filamentous algae. Further physiological experiments found that Oscillatoria showed specific eco-physiological responses to different macrophyte species. Hydrilla verticillata and C. oryzetorum promoted growth and photosynthetic activity of Oscillatoria, while Potamogeton malaianus inhibited growth and P uptake of PO. Myriophyllum spicatum exhibited no impact on growth of Oscillatoria. Our results revealed the intrinsic (physiological differences between free-floating and periphytic life forms of filamentous algae) and extrinsic (different macrophytes) factors affect the proliferation of filamentous algae, which are important for guidance on planting of submerged macrophytes during lake restoration.

2.
J Affect Disord ; 260: 349-360, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31521873

RESUMO

BACKGROUND: Symptomatology differences of major depressive disorder (MDD) in psychiatric and general hospitals in China leads to possible misdiagnosis. Looking at the symptomatology of first-visit patients with MDD in different mental health services, and identifying predictors of health-seeking behavior using machine learning may help to improve diagnostic accuracy. METHODS: 1500 patients first diagnosed with MDD were recruited from 16 psychiatric hospitals and 16 general hospitals across China. Socio-demographic characteristics, causal attribution, symptoms of depression within and outside Diagnostic and Statistical Manual of Mental Disorders (DSM) framework were collected using a self-made questionnaire. A predictive model of 62 variables was established using Random forest, symptom frequencies of patients in general hospitals and psychiatric hospitals were compared. RESULTS: The machine learning approach revealed that symptoms were strong predictors of health-seeking behavior among patients with MDD. General hospitals patients had higher frequencies of suicidal ideation (χ2=15.230, p<0.001), psychosis (χ2=14.264, p<0.001), weight change (all p<0.001), hypersomnia (χ2=25.940, p<0.001), and a tendency of denying emotional/cognitive symptoms compared with psychiatric hospitals patients. LIMITATIONS: Stigma and preference bias were not measured. Severity of current depressive episodes was not assessed. Data of previous episode(s) was not presented. CONCLUSIONS: Symptom evaluation targeting specific patient population in different hospitals is crucial for diagnostic accuracy. Suicide prevention reliant on collaboration between general hospitals and psychiatric hospitals is required in the future construction of Chinese mental health system.

3.
Toxicol Lett ; 318: 30-43, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31647946

RESUMO

Lead (Pb), a widespread heavy metal, may induce serious diseases, particularly male reproductive injury. However, the mechanisms by which Pb induces testicular injury remain unclear. In this paper, we established a mouse model of Pb-induced testicular injury via an intraperitoneal injection of lead chloride at a concentration of 1.5 mg/kg body weight. We confirmed that Pb could induce a series of injuries, including a low litter size, smaller testes, more weak offspring, direct injury, and aberrant spermiogenesis. Our study demonstrated that Pb could inhibit lysine acetylation (Kac) and succinylation (Ksuc) via western blot (WB) and immunofluorescence (IF) analyses. We subsequently separated different germ cells that contained Pre-meiotic spermatogonia (SPG), meiotic spermatocyte (SPC), and round spermatid (RS) into the Pb-treated and control groups and verified that Pb inhibited Kac in SPC, RS, and particularly, during meiosis. Furthermore, our results regarding the inhibition of pyruvate kinase and mitochondrial electron transport chain complex I and II in the Pb-treated groups suggested that Pb may restrain key enzymes to block the TCA cycle and that the low TCA cycle activity could reduce the contents of two important metabolites, acetyl-CoA and succinyl-CoA, to inhibit Kac and Ksuc. Moreover, we examined the influences of the inhibition of Kac and Ksuc on spermiogenesis, which indicated that decreased Kac and Ksuc could impede the replacement of transition proteins in elongating sperm and disorder the distribution of germ cells in the seminiferous tubule. Our research provides novel insights into the mechanisms of Pb reproductive toxicity with respect to lysine acetylation and succinylation.


Assuntos
Chumbo/toxicidade , Lisina/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Espermatogênese/efeitos dos fármacos , Espermatozoides/efeitos dos fármacos , Testículo/efeitos dos fármacos , Acetilação , Animais , Metabolismo Energético/efeitos dos fármacos , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Espermatozoides/metabolismo , Espermatozoides/patologia , Testículo/metabolismo , Testículo/patologia
4.
Bioresour Technol ; 295: 122242, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31629282

RESUMO

Phytohormones comprise a variety of trace bioactive compounds that can stimulate cell growth and promote metabolic shifts. In the present work, a two-stage screening strategy was innovatively established to identify positive phytohormones for enhancement of astaxanthin and lipid coproduction in microplate-based cultures of mixotrophic Chromochloris zofingiensis. The results showed that auxins were the most efficient stimulators for astaxanthin accumulation. The maximum content of 13.1 mg/g and yield of 89.9 mg/L were obtained using indole propionic acid (10 mg/L) and indoleacetic acid (7.8 mg/L), representing the highest levels of astaxanthin in this microalga reported to date. Total lipids with the highest content (64.5% DW) and productivity (445.7 mg/L/d) were coproduced with astaxanthin using indoleacetic acid. Statistical analysis revealed close relations between phytohormones and astaxanthin and lipid biosynthesis. This study provides a novel original strategy for improving astaxanthin and lipid coproduction in C. zofingiensis using the selected phytohormones as positive stimulators.


Assuntos
Chlorella , Microalgas , Lipídeos , Reguladores de Crescimento de Planta , Xantofilas
5.
Mol Cell Endocrinol ; 499: 110603, 2020 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-31574295

RESUMO

Activin/Smad3 signaling plays a pivotal role in follicle development and atresia. However, the precise mechanisms underlying this process are not yet fully understood. Herein, we identified miR-181a as a central component of activin/Smad3-mediated follicle atresia. miR-181a was strikingly upregulated in porcine atretic follicles, which induced the apoptosis of porcine granulosa cells (GCs) in vitro. Furthermore, the transforming growth factor-ß type 1 receptor (TGFBR1) was confirmed as a direct target of miR-181a by bioinformatics analysis and luciferase assays. Transfection with an miR-181a agomir repressed the TGFBR1 mRNA and protein levels. In addition, TGFBR1 overexpression repressed GC apoptosis, whereas TGFBR1 inhibition promoted GC apoptosis. miR-181a overexpression downregulated the phosphorylation of Smad3 and blocked the activation of TGF-ß signaling. Moreover, activin A downregulated miR-181a expression and upregulated the TGFBR1 and p-Smad3 protein levels. Collectively, these data suggest that miR-181a regulates porcine GC apoptosis by targeting TGFBR1 via the activin signaling pathway.

6.
Ann Lab Med ; 40(2): 155-163, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31650732

RESUMO

BACKGROUND: LINC01234, a long noncoding RNA (lncRNA), is overexpressed in several cancers, including colorectal cancer (CRC). We investigated the role of LINC01234 in CRC development and confirmed its correlation with Krüppel-like factor 6 (KLF6), a tumor suppressor gene that is dysregulated in CRC. METHODS: We tested mRNA levels using quantitative reverse transcription PCR (qRT-PCR). Tissue samples from patients with CRC, inflammatory bowel disease (IBD), hyperplastic polyp, and adenoma were included. Correlations between clinicopathological parameters, overall survival (OS) rate, and LINC01234 were analyzed using Kruskal-Wallis H test. Additionally, cell proliferation, apoptosis, and tumor formation in nude mice were tested to investigate the mechanism of LINC01234. Western blotting was used to determine protein levels. RESULTS: LINC01234 expression was significantly upregulated in CRC tissues and CRC cell lines than in non-tumor tissues and normal epithelial cells, respectively. LINC01234 was associated with high tumor stage, larger tumor size, and metastasis. Patients with higher LINC01234 expression showed reduced OS. Cell proliferation was inhibited by LINC01234 knockdown, whereas apoptosis was enhanced. Mice injected with SW480 cells with LINC01234 knockdown displayed decreased tumor volume, weight, and Ki-67 levels compared with those injected with control cells. KLF6 was negatively regulated by LINC01234. Overexpression of KLF6 showed effects similar to those observed following LINC01234 knockdown on cell proliferation and apoptosis. CONCLUSIONS: LINC01234 could be a prognostic biomarker in CRC patients. Upregulation of LINC01234 in CRC promotes tumor development through negative regulation of KLF6.

7.
Toxicol In Vitro ; 62: 104667, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31629901

RESUMO

Serum is an important component in cell culture medium. It also possesses potent antioxidant properties. Therefore, the conventional protocols for detecting reactive oxygen species (ROS) in cultured cells with fluorescent probes include washing and suspending cells with serum-free buffers, such as PBS. This transient serum deprivation is essential for the ROS detecting. Unfortunately, it may also cause unexpected results, which push us to choose more optimal experiment conditions. In the present study, we found an acute lytic cell death induced by xanthohumol (XN), which obstructed ROS detecting in human leukemia cell line HL-60 cells. XN induced ROS burst, caused cell swelling, membrane permeability increase, LDH release, and ultimately an acute lytic cell death and cell rupture. These effects could be alleviated by the antioxidant N-Acetyl-L-cysteine (NAC). Apoptosis, pyroptosis or necroptosis were not observed in this process. Results also indicated that 2% serum addition had already completely scavenged ROS induced by 10 µM XN. Taken together, it is strongly suggested to detecting ROS in a serum-free medium when studying where and how ROS generated in cells. The concentration at the ROS maximum point (10 µM XN in this study) can be selected as the optimal concentration.

8.
Sensors (Basel) ; 19(22)2019 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-31717598

RESUMO

Enrichment of cadmium ion (Cd2+) from the environment may lead to kidney disease and weakened immunity in the body. Current techniques are not convenient enough to measure Cd2+ concentration in the environment due to low sensitivity and poor linear range. In this paper, a new measurement technique is proposed using a new sensing electrode made of nano-copper-enhanced carbon fiber. Nano-copper was deposited onto the surface of carbon fiber to enhance the current concentration and mass transfer rate of Cd2+ during measurement, which improved the electrochemical detection sensitivity significantly (by up to 3.7 × 108 nA/nM) and broadened the linear range to 10~105 nM. This device provides a low-cost solution for measuring Cd2+ concentration in the environment.

9.
J Biomol Struct Dyn ; : 1-21, 2019 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-31684825

RESUMO

We prepared extracts of Alisma orientalis from Sichuan and Fujian Province, China. Based on the ratio of alisol B 23-acetate (23B) to alisol A 24-acetate (24A) in two Alisma orientalis extracts, we prepared two mixtures of 24A and 23B (24A:23B = 1:3 or 1:10). The antitumor molecular mechanism of the monomers 24A and 23B, the two mixtures and the effective components of Alisma orientalis from different habitats were studied. The MTT assay suggested that the difference in the antitumor activity of Alisma orientalis from different habitats was correlated to the ratio of 24A to 23B. The multi-spectroscopic analysis suggested that the effective components, the monomers and mixtures interacted with c-myc DNA in a partial intercalation manner. The binding strength of the alisol acetates to c-myc DNA was consistent with the anticancer activity, indicating that c-myc DNA was the anticancer target. The molecular simulation indicated that the mixtures were all directly bound to different base pairs of c-myc DNA for a superimposed effect, which led to the binding strength of the mixtures to c-myc DNA was stronger than that of the monomers. The molecules in the 1:3 mixture were all bound to different base pairs of c-myc DNA. However, for the 1:10 mixture, seven molecules of 23B bound to the side chain of 24A, resulting in the mixture with a long chain structure which increased the steric hindrance of 24A. As a result, affinity between 24A and c-myc DNA in the 1:10 mixture was weaker than that in the 1:3 mixture.The antitumor molecular mechanism of the alisol monomers 24A and 23B, the mixtures with different proportions and the effective components of Alisma orientalis from different habitats were studied. The order of the antitumor activity was as follows: Sichuan > Fujian, 24A-23B (1:3) > 24A-23B (1:10) > 23B > 24A. The antitumor activity of Alisma orientalis from different habitats was consistent with the mixtures which were designed according to the contents of the active ingredients of the medicinal materials, indicating that the antitumor activity of Alisma orientalis from Sichuan is better than that from Fujian which is related to the contents of 24A and 23B and the proportion of 1:3 is better than 1:10. The binding strength of the mixtures to c-myc DNA was consistent with the anticancer activity. The mixtures were all directly bound to different base pairs of c-myc DNA for a superimposed effect, which led to the strength of the interaction of the mixtures to c-myc DNA was stronger than that of the monomers. For the 24A-23B (1:3) mixture, the four small molecules bound to c-myc DNA directly and interacted with different base pairs of c-myc DNA. While for the 24A-23B (1:10) mixture, 24A and three 23B molecules interacted with c-myc DNA, the remaining seven 23B molecules bound to the side chain of 24A, which increased the steric hindrance. The binding of the mixture to c-myc DNA was decreased.

10.
Artigo em Inglês | MEDLINE | ID: mdl-31714687

RESUMO

OBJECTIVE: To evaluate the feasibility, safety, and effectiveness of a novel, absorbable atrial septal defect (ASD) closure device made of poly-l-lactic acid (PLLA) in a swine model of ASD and for the first time in humans. METHODS: A preclinical safety study was conducted using a swine model of ASD. In a clinical setting, five pediatric patients underwent ASD closure with the PLLA device with fluoroscopic and transthoracic echocardiography guidance. The procedural results and clinical outcomes at 1 day, 30 days, 3 months, and 6 months after closure were analyzed. RESULTS: The 24- and 36-month follow-up results of the preclinical study demonstrated that the PLLA device exhibited good endothelialization and degradability in the swine model. In the clinical study, successful device implantation was achieved in all five patients (median age, 3.6 years; range, 3.1-6.5 years). The mean defect size was (13.6 ± 2.7) mm. Follow-up at 30 days, 3 months, and 6 months was completed in all five cases. The complete defect closure rates with no residual shunt at 30 days, 3 months, and 6 months follow-up were 60% (3/5), 80% (4/5), and 80% (4/5), respectively. No device dislodgement, significant aortic valve or mitral valve regurgitation, new onset cardiac arrhythmia, or other adverse events were reported. CONCLUSION: The study results demonstrated that it is feasible to implant the PLLA device for closure of small to medium sized ASDs without significant residual shunts or severe adverse events in humans. The PLLA device exhibited good endothelialization and degradability in the swine model at 24 and 36 months. Further studies to evaluate long-term safety and effectiveness with the device in a large cohort of patients are warranted.

11.
Medicine (Baltimore) ; 98(44): e17668, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31689781

RESUMO

BACKGROUND: Previous studies have reported that both arthroscopic debridement (AD) and open debridement (OD) of extensor carpi radialis brevis are effective in the treatment of lateral epicondylitis. Despite this, few studies have focused on the comparative outcomes of these 2 procedures. The aim of this study was to assess whether AD is superior to OD in managing lateral epicondylitis. METHODS: A systematic search of the literature was conducted to identify relevant articles that were published in MEDLINE, Embase, and Cochrane Library databases during January 2019. All studies comparing the efficacy of AD and OD in terms of failure rate, complication rate, and clinical outcome measures were included. Statistical analysis was performed using Review Manager. RESULTS: Six clinical trials were included in the current meta-analysis. There was no significant difference with regard to disabilities of the arm, shoulder, and hand scores, visual analog scale, and failure rate. There was a statistically significant difference in surgical time in favor of the OD (mean difference [MD], -11.45, 95% confidence interval [CI], -12.45 to -10.44, I = 0%, P < .001). There was no significant difference of complication rate between the OD group (0.6%) and the AD group (1.0%) (MD, 0.62; 95% CI, 0.12-3.06; P = .55) CONCLUSION:: There was no significant difference between arthroscopic and open surgery with regards to failure rate, functional outcome score, and complication rate. The current meta-analysis found that arthroscopic surgery had a longer surgical time than open surgery for lateral epicondylitis.

12.
Artigo em Inglês | MEDLINE | ID: mdl-31758817

RESUMO

We conducted this research in order to investigate the potential of a new material called glass pumice for use as a microorganism immobilization carrier to improve aquaculture pond water quality. The pH adjustment capacity and the Rhodopseudomonas palustris P1 cell adsorption capacity of glass pumice were measured. The immobilized Rps. palustris P1 and the free sample were compared to determine which had an enhanced NH4 + -N and NO2 - -N removal efficiency. The results showed that glass pumice significantly affected the pH of the acid solution (P < 0.05); the pH increased from 3.0 ± 0.08 to 7.21 ± 0.13 in 12 h. Rps. palustris P1 adsorption to glass pumice was rapid and reached equilibrium within 60 min. The Langmuir adsorption parameter data showed that glass pumice had a higher affinity for Rps. palustris P1 than SiO2 powder, with an adsorption capacity of 4.02 × 108 cells g-1 . The maximum NH4 + -N and NO2 - -N removal rates by immobilized Rps. palustris P1 were 134.82 ± 0.67 % and 93.68 ± 0.14 % higher than those of non-immobilized P1, respectively. Based on the above results, we propose that glass pumice is potential as a microorganism carrier material in aquaculture water treatment. This article is protected by copyright. All rights reserved.

13.
Asian J Androl ; 2019 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-31710002

RESUMO

Intraductal carcinoma of the prostate (IDC-P) is an aggressive pathological pattern of prostate cancer (PCa). We investigated the association of IDC-P in prostate biopsy (PBx) with several pathological features after radical prostatectomy (RP) and its prognostic value in high-risk PCa. A total of 418 patients with high-risk PCa after RP were included in this study. IDC-P and its architectural patterns were identified according to the 2016 World Health Organization Classification. Chi-squared test and logistic regression were used to investigate the correlation between IDC-P and post-RP pathological features. Kaplan-Meier curves and Cox regression were applied to explore the prognostic value of IDC-P. IDC-P was identified in PBx in 36/418 (8.6%) patients. Logistic regression indicated that IDC-P in PBx was independently associated with several pathological features of RP, including Gleason score 8-10 (P < 0.001), seminal vesicular invasion (P < 0.001), and pathological T (pT) 3a (P = 0.043). Patients with IDC-P in PBx manifested poorer biochemical-free survival (BFS) than those without IDC-P (37.47 months vs not reached, P < 0.001). The addition of IDC-P in several prognostic nomograms could improve the predictive accuracy of these tools. We conclude that IDC-P in PBx is positively associated with several aggressive pathological features after RP in high-risk PCa. In addition, IDC-P in PBx could effectively predict the BFS of high-risk PCa patients after RP.

14.
Oral Dis ; 2019 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-31710746

RESUMO

OBJECTIVE: We determined the bacterial community structure of the buccal mucosa in patients with oral lichen planus (OLP) and evaluated the potential association of Fusobacterium nucleatum with OLP. SUBJECTS AND METHODS: We collected buccal mucosal swab samples of patients with OLP (n = 20) and healthy controls (n = 10) and performed 16S rRNA gene sequencing and real-time PCR to determine potentially different bacteria. Damaged and adjacent non-damaged mucosal swab samples of 25 OLP patients were used to detect the amount of F. nucleatum by real-time PCR. RESULTS: Compared with healthy controls, enrichment of Fusobacterium and Granulicatella was more abundant in patients with OLP (p = .0146 and 0.0034). The abundance of Fusobacterium and F. nucleatum was significantly enriched on buccal mucosa of patients with OLP compared with healthy controls (p = .0043 and 0.0235). Compared with adjacent non-damaged buccal mucosa of OLP patients, the amount of F. nucleatum in the damaged mucosa was significantly increased (p = .001). We examined third-level KEGG pathways for bacteria on mucosal surface and found that genes controlling sporulation and ether lipid metabolism were enriched in patients with OLP. CONCLUSIONS: A high amount of F. nucleatum may be associated with OLP. Further studies are required to investigate the precise association of F. nucleatum with OLP.

15.
Sci Total Environ ; 701: 134930, 2019 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-31726410

RESUMO

Natural and synthetic progestogens in livestock environments have become a concern due to the frequent presence and potential adverse effects on aquatic organisms. Here we investigated the biotransformation of progestogens by wastewater-borne bacteria in the field and laboratory under oxic and anoxic conditions. The results showed that all progestogens dissipated faster under oxic conditions than under anoxic conditions, and natural progesterone transformed faster than synthetic progestogens. Meanwhile, dozens of bacterial strains capable of degrading progestogens were successfully isolated from the swine wastewater, and Bacillus sp. P19 and Bacillus sp. DGT2 were found the best for progesterone and dydrogesterone transformation, respectively. In the degradation experiments using a single bacterial strain, progesterone and dydrogesterone dissipated under oxic conditions with half-lives of 11.6 h and 18.2 h, respectively. The transformation pathways were proposed based on the identified transformation products. The findings from this study showed that progestogens can be biotransformed, but not fully mineralized in the environment.

16.
Nucleic Acids Res ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31745563

RESUMO

Cross-species pathway transplantation enables insight into a biological process not possible through traditional approaches. We replaced the enzymes catalyzing the entire Saccharomyces cerevisiae adenine de novo biosynthesis pathway with the human pathway. While the 'humanized' yeast grew in the absence of adenine, it did so poorly. Dissection of the phenotype revealed that PPAT, the human ortholog of ADE4, showed only partial function whereas all other genes complemented fully. Suppressor analysis revealed other pathways that play a role in adenine de-novo pathway regulation. Phylogenetic analysis pointed to adaptations of enzyme regulation to endogenous metabolite level 'setpoints' in diverse organisms. Using DNA shuffling, we isolated specific amino acids combinations that stabilize the human protein in yeast. Thus, using adenine de novo biosynthesis as a proof of concept, we suggest that the engineering methods used in this study as well as the debugging strategies can be utilized to transplant metabolic pathway from any origin into yeast.

17.
Artigo em Inglês | MEDLINE | ID: mdl-31745767

RESUMO

Conversion of FeII(EDTA)-NO or FeIII(EDTA) into FeII(EDTA) is a key process in a wet flue gas denitrification technology with FeII(EDTA) solution. In this work, the stoichiometry, kinetics, and thermodynamics of FeII(EDTA)-NO reduction by Mn powder were investigated. We first studied the FeII(EDTA)-NO reduction and product distribution to speculate a possible stoichiometry of FeII(EDTA)-NO reduction by Mn powder. Then, the effects of major influencing factors, such as pH value, temperature, and Mn concentration, were studied. The pseudo-second-order model was established to describe the FeII(EDTA)-NO reduction. Simultaneously, according to Arrhenius and Eyring-Polanyi equations, the reaction activation energy (Ea), enthalpy of activation (∆H‡), and entropy of activation (∆S‡) were calculated as 23.68 kJ/mol, 21.148 kJ/mol, and - 149.728 J/(k mol), respectively. Additionally, simultaneous reduction of FeIII(EDTA) and FeII(EDTA)-NO was investigated to better study the mechanism of FeII(EDTA) regeneration, suggesting that there was a competition between the two reduction processes. Finally, a simple schematic mechanism of NO absorption by FeII(EDTA) combined with regeneration of manganese ion and ammonium was proposed. These fundamental researches could offer a valuable guidance for wet flue gas denitrification technology with FeII(EDTA) solution.

18.
Org Lett ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746212

RESUMO

Catalytic enantioselective chemical reactions involving highly reactive radical species remain largely unexplored. We report herein for the first time a novel enantioselective radical ring-opening cyanation of redox-active oxime esters by dual photoreodox and copper catalysis. This mild protocol shows good functional group tolerance and broad substrate scope, producing a wide range of optically active alkyl dinitriles with high yields and excellent enantioselectivities, which are difficult to access traditionally.

19.
Chem Commun (Camb) ; 2019 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-31746851

RESUMO

Mitochondrial targeting of drugs largely relies on delocalized lipophilic cations. Nevertheless, mitochondrial membrane potentials in cancer cells are inconstant, which could compromise stable mitochondrial targeting. Herein, we further validated a mitochondrial temperature-dependent drug delivery strategy in vivo. Thermoresponsive drug delivery to mitochondria may represent a promising strategy for cancer therapy.

20.
Life Sci ; 239: 116877, 2019 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-31669575

RESUMO

AMP-activated protein kinase (AMPK) is induced by the exhaustion of cellular energy and activates adaptive alterations in cellular metabolism, which is the basis for cell survival during different environmental stresses. We aimed to investigate the biological functions of AMPK and its molecular mechanism in regulating thyroid cancer (TC) progression. In current study, we found that activation of AMPK by multiple agonists suppresses TC cell proliferation. However, AMPK activation also led to TC cell migration at the same time. Depletion of AMPK abolished the effect of its agonist on cell multiplication and migration. Mechanistic investigations revealed that the impact of AMPK in terms of cell migration is dependent on its nuclear translocation, since site mutation of AMPK in its nuclear translocation domain (K244A) abolished TC cell migration but did not affect the inhibition of cell proliferation by AMPK agonist. Moreover, the nuclear AMPK recruits PKM2 and ß-catenin by their interaction, which promotes the transcription of cell migration related genes, including MMP7 and c-Myc. Furthermore, depletion of PKM2/ß-catenin abolished the migration effect of AMPK agonists, but did not affect their effects on suppression of cell proliferation. Our results provided a novel function of AMPK in cancer migration, and suggested that a combination of AMPK activation and PKM2 depletion or inhibition can be a new strategy to achieve better therapeutic effects for TC patients.

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