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1.
Nat Commun ; 15(1): 5578, 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38956103

RESUMO

Diatoms often outnumber other eukaryotic algae in the oceans, especially in coastal environments characterized by frequent fluctuations in light intensity. The identities and operational mechanisms of regulatory factors governing diatom acclimation to high light stress remain largely elusive. Here, we identified the AUREO1c protein from the coastal diatom Phaeodactylum tricornutum as a crucial regulator of non-photochemical quenching (NPQ), a photoprotective mechanism that dissipates excess energy as heat. AUREO1c detects light stress using a light-oxygen-voltage (LOV) domain and directly activates the expression of target genes, including LI818 genes that encode NPQ effector proteins, via its bZIP DNA-binding domain. In comparison to a kinase-mediated pathway reported in the freshwater green alga Chlamydomonas reinhardtii, the AUREO1c pathway exhibits a faster response and enables accumulation of LI818 transcript and protein levels to comparable degrees between continuous high-light and fluctuating-light treatments. We propose that the AUREO1c-LI818 pathway contributes to the resilience of diatoms under dynamic light conditions.


Assuntos
Aclimatação , Diatomáceas , Luz , Diatomáceas/metabolismo , Diatomáceas/genética , Diatomáceas/efeitos da radiação , Chlamydomonas reinhardtii/metabolismo , Chlamydomonas reinhardtii/genética , Chlamydomonas reinhardtii/efeitos da radiação , Proteínas de Algas/metabolismo , Proteínas de Algas/genética , Regulação da Expressão Gênica/efeitos da radiação
2.
Sci Rep ; 14(1): 13661, 2024 06 13.
Artigo em Inglês | MEDLINE | ID: mdl-38871732

RESUMO

Over the past decades, the immune responses have been suspected of participating in the mechanisms for epilepsy. To assess the immune related pathway in temporal lobe epilepsy (TLE), we explored the altered immune pathways in TLE patients with and without hippocampal sclerosis (HS). We analyzed RNA-seq data from 3 TLE-HS and 3 TLE-nonHS patients, including identification of differentially expressed RNA, function pathway enrichment, the protein-protein interaction network and construction of ceRNA regulatory network. We illustrated the immune related landscape of molecules and pathways on human TLE-HS. Also, we identified several differential immune related genes like HSP90AA1 and SOD1 in TLE-HS patients. Further ceRNA regulatory network analysis found SOX2-OT connected to miR-671-5p and upregulated the target gene SPP1 in TLE-HS patients. Also, we identified both SOX2-OT and SPP1 were significantly upregulated in five different databases including TLE-HS patients and animal models. Our findings established the first immune related genes and possible regulatory pathways in TLE-HS patients and animal models, which provided a novel insight into disease pathogenesis in both patients and animal models. The immune related SOX2-OT/miR-671-5p/SPP1 axis may be the potential therapeutic target for TLE-HS.


Assuntos
Epilepsia do Lobo Temporal , Redes Reguladoras de Genes , Esclerose Hipocampal , MicroRNAs , Fatores de Transcrição SOXB1 , Adulto , Animais , Feminino , Humanos , Masculino , Epilepsia do Lobo Temporal/genética , Epilepsia do Lobo Temporal/imunologia , Epilepsia do Lobo Temporal/fisiopatologia , Perfilação da Expressão Gênica , Esclerose Hipocampal/imunologia , Esclerose Hipocampal/fisiopatologia , MicroRNAs/genética , MicroRNAs/metabolismo , Osteopontina/genética , Osteopontina/metabolismo , Mapas de Interação de Proteínas , Fatores de Transcrição SOXB1/genética , Fatores de Transcrição SOXB1/metabolismo
3.
J Colloid Interface Sci ; 662: 1005-1015, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38387362

RESUMO

A novel strategy for better catalytic performance in terms of precisely tuning the metal atom number of active centers is gradually getting attention. In this paper, the Co atom pair sites on N-doped porous carbon was engineered. The binuclear Co2 site structure was identified by aberration-corrected scanning transmission electron microscopy and X-ray absorption spectroscopy. As expected, the Co2NC display an outstanding Fenton-like catalysis activity in tetracycline degradation with turnover frequency exceeding 0.91 min-1 that is approximately 4 times higher than the conventional CoN4 site. The EPR tests indicated that the ROS strength stimulated by the binuclear site was much stronger than that of single site. Theoretical density functional theory calculations reveal that the optimized adsorption configuration is the O1 of peroxymonosulfate (PMS) interacting with two Co atoms, leading to stronger interaction effect and electron transfer for PMS comparing to single atom sites.

4.
Clin J Gastroenterol ; 16(6): 793-802, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37740882

RESUMO

The clinical benefits and safety of hepatic arterial infusion chemotherapy (HAIC) combined with sorafenib versus sorafenib alone for advanced HCC are inconsistent in clinical studies. This meta-analysis aims to evaluate the effectiveness and safety of HAIC combined with sorafenib versus sorafenib alone for advanced hepatocellular carcinoma (HCC). We searched the database up to March 1, 2023, for studies evaluating the effectiveness and safety of HAIC combined with sorafenib versus sorafenib alone for advanced HCC. This study was registered in PROSPERO (CRD42022323712). Outcomes included overall survival (OS), progression-free survival (PFS), objective response rate (ORR), diseases control rate (DCR), and adverse effects (AEs). The hazard ratio (HR) and odd ratio (OR) with 95% confidence intervals (CI) were used to measure the pooled effect. Six studies with 318 patients in the combination group and 338 patients in the control group were included. Meta-analysis showed that HAIC combined with sorafenib significantly improves OS compared with sorafenib alone (HR = 9.70, 95% CI 4.52-20.82] and HAIC combined with sorafenib significantly improves PFS compared with sorafenib alone (HR = 9.48, 95% CI 4.47-20.13). Besides, HAIC combined with sorafenib did not show significantly advantage of DCR rate (OR = 1.85, 95% CI 0.93-3.69), but associated with higher rates of ORR compared with sorafenib alone (OR = 9.85, 95% CI 3.05-31.85). HAIC combined with sorafenib can achieve a better effect and survival benefits than sorafenib alone in patients with advanced HCC, but the limitation should be treated with cautions.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Sorafenibe/efeitos adversos , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Resultado do Tratamento , Protocolos de Quimioterapia Combinada Antineoplásica/efeitos adversos , Infusões Intra-Arteriais/efeitos adversos
5.
Nat Nanotechnol ; 18(10): 1168-1174, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37474685

RESUMO

Minimizing heat accumulation is essential to prolonging the operational lifetime of quantum dot light-emitting diodes (QD-LEDs). Reducing heat generation at the source is the ideal solution, which requires high brightness and quantum efficiency at low driving voltages. Here we propose to enhance the brightness of QD-LEDs at low driving voltages by using a monolayer of large QDs to reduce the packing number in the emitting layer. This strategy allows us to achieve a higher charge population per QD for a given number of charges without charge leakage, enabling enhanced quasi-Fermi-level splitting and brightness at low driving voltage. Due to the minimized heat generation, these LEDs show a high power conversion efficiency of 23% and a T95 operation lifetime (the time for the luminance to decrease to 95% of the initial value) of more than 48,000 h at 1,000 cd m-2.

6.
Nanoscale ; 15(8): 3585-3593, 2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36727444

RESUMO

As the emitters of quantum dots (QDs) light-emitting diodes (QLEDs), QDs, which are responsible for the charge injection, charge transportation, and especially exciton recombination, play a significant role in QLEDs. With the crucial advances made in QDs, such as the advancement of synthetic methods and the understanding of luminescence mechanisms, QLEDs also demonstrate a dramatic improvement. Until now, efficiencies of 30.9%, 28.7% and 21.9% have been achieved in red, green and blue devices, respectively. However, in QLEDs, some issues are still to be solved, such as the imbalance of charge injection and exciton quenching processes (defect-assisted recombination, Auger recombination, energy transfer and exciton dissociation under a high electric field). In this review, we will provide an overview of recent advances in the study and understanding of the working mechanism of QLEDs and the exciton quenching mechanism of QDs in devices. Particular emphasis is placed on improving charge injection and suppressing exciton quenching. An in-depth understanding of this progress may help develop guidelines to direct QLED development.

7.
Proc Natl Acad Sci U S A ; 120(9): e2219952120, 2023 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-36802416

RESUMO

Social behavior starts with dynamic approach prior to the final consummation. The flexible processes ensure mutual feedback across social brains to transmit signals. However, how the brain responds to the initial social stimuli precisely to elicit timed behaviors remains elusive. Here, by using real-time calcium recording, we identify the abnormalities of EphB2 mutant with autism-associated Q858X mutation in processing long-range approach and accurate activity of prefrontal cortex (dmPFC). The EphB2-dependent dmPFC activation precedes the behavioral onset and is actively associated with subsequent social action with the partner. Furthermore, we find that partner dmPFC activity is responsive coordinately to the approaching WT mouse rather than Q858X mutant mouse, and the social defects caused by the mutation are rescued by synchro-optogenetic activation in dmPFC of paired social partners. These results thus reveal that EphB2 sustains neuronal activation in the dmPFC that is essential for the proactive modulation of social approach to initial social interaction.


Assuntos
Córtex Pré-Frontal , Receptor EphB2 , Comportamento Social , Animais , Camundongos , Encéfalo , Neurônios/fisiologia , Córtex Pré-Frontal/fisiologia , Receptor EphB2/genética , Receptor EphB2/fisiologia
8.
Acta Clin Belg ; 78(2): 171-179, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35587164

RESUMO

BACKGROUND: We carried out a systematic review and meta-analysis to assess the safety and effectiveness of hepatic arterial infusion chemotherapy (HAIC) compared with transarterial chemoembolization (TACE) for patients with unresectable hepatocellular carcinoma (uHCC). METHODS: Eligible studies were searched by MEDLINE, the Cochrane Library, Embase, and Web of Science from January 1995 to January 2022, investigating eligible literature comparing HAIC and TACE for patients with HCC. The main outcome measures included progression-free survival (PFS), overall survival (OS), adverse events (AEs), objective response rate (ORR), and diseases control rate (DCR). RESULTS: Eight literature and 1028 patients were enrolled in this meta-analysis. The pooled PFS, OS, ORR, and DCR were HR = 0.89 (95% CI, 0.81-0.98), HR = 0.84 (95% CI, 0.75-0.93), OR = 2.77 (95% CI, 2.01-3.80), and OR = 4.64 (95% CI, 2.40-8.99), respectively. The adverse events of HAIC were lower than TACE. CONCLUSION: Our meta-analysis revealed that HAIC can achieve a better effect and survival benefits than TACE in patients with uHCC.


Assuntos
Carcinoma Hepatocelular , Quimioembolização Terapêutica , Neoplasias Hepáticas , Humanos , Carcinoma Hepatocelular/tratamento farmacológico , Carcinoma Hepatocelular/patologia , Neoplasias Hepáticas/tratamento farmacológico , Neoplasias Hepáticas/patologia , Quimioembolização Terapêutica/efeitos adversos , Infusões Intra-Arteriais , Resultado do Tratamento
9.
Environ Geochem Health ; 45(6): 3805-3816, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36577857

RESUMO

Organophosphate esters (OPEs) are emerging pollutants. Currently, research on OPEs in tree rings is still limited. In this study, tree rings of five arbor species from Sichuan Province, China, were sampled to study the occurrence and distribution of six OPEs, which were quantitatively analyzed by gas chromatography-mass spectrometry (GC-MS). The total concentrations of OPEs in all samples ranged from 189.79 (Fir species) to 341.23 ng/g (Toona sinensis), with average concentration of 284.77 ± 46.66 ng/g. So, arbor could be used as good passive samplers for OPEs. The levels of OPEs among five arbor species showed no significant difference (p = 0.668 > 0.05), suggesting that the pollution status of OPEs in a region or country could be roughly assessed by any arbor tree species. In this study area, tris(2-butoxyethyl) phosphate (TBEP) was the dominant OPEs followed by tri(2-chloroethyl) phosphate (TCEP). Tris(2-ethylhexyl) phosphate (TEHP) and tri-n-butyl phosphate (TnBP) showed relatively stable concentrations in each arbor species, while the other four OPEs including TBEP, triphenyl phosphate (TPhP), tri(chloropropyl) phosphate (TCPP) and TCEP had significantly different concentrations. Interestingly, the absorption and accumulation of OPEs by tree rings of arbor species were quite different from that of inorganic elements reported by other studies.


Assuntos
Monitoramento Ambiental , Retardadores de Chama , Monitoramento Ambiental/métodos , Ésteres/análise , Retardadores de Chama/análise , Organofosfatos/análise , China , Fosfatos/análise
10.
Huan Jing Ke Xue ; 43(11): 4992-4999, 2022 Nov 08.
Artigo em Chinês | MEDLINE | ID: mdl-36437071

RESUMO

As a type of emerging pollutant of concern, organophosphate esters (OPEs) have posed a moderate risk to the remote Antarctic waters. Triphenyl phosphate (TPHP) is a common type of OPEs in water, which has been proven to have toxic effects, bioaccumulation, and amplification effects and pose a great threat to the environment and human health. Fourier transform infrared spectroscopy (FT-IR) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to investigate the degradation process of TPHP in three advanced oxidation processes (UV-AOPs), including ultraviolet-hydrogen peroxide (UV-H2O2), ultraviolet-titanium dioxide (UV-TiO2), and ultraviolet-persulfate (UV-PS) systems. This was the first instance of using FT-IR for the online observation of the change in infrared characteristic peaks in the degradation process of TPHP, and its degradation reaction kinetics, photodegradation products, and degradation pathways were analyzed. The results showed that TPHP could be effectively degraded under UV-H2O2, UV-TiO2, and UV-PS systems, and the photodegradation half-lives were 74, 150, and 89 min, respectively. The UV-H2O2 system had the best degradation effect on TPHP. Additionally, the degradation reactions of TPHP in three systems conformed to the first-order kinetics. When the concentration of H2O2 was 0-0.097 mol·L-1, the increase in H2O2 concentration promoted the degradation of TPHP, and when the concentration of TiO2 was 0-0.013 mol·L-1, the increase in TiO2 concentration promoted the degradation of TPHP. The photodegradation pathway of TPHP mainly included the P-O-C bond breaking, the C-H bond cleavage of the benzene ring structure and the hydrolysis reaction of TPHP. The UV-H2O2 system was used to degrade OPEs in the environmental water of Chengdu, and it was found that the removal rate of TPHP was 66% when the water samples of the park landscape water were degraded for 60 min.


Assuntos
Peróxido de Hidrogênio , Água , Humanos , Peróxido de Hidrogênio/química , Cromatografia Líquida , Espectroscopia de Infravermelho com Transformada de Fourier , Raios Ultravioleta , Espectrometria de Massas em Tandem , Organofosfatos
11.
World J Clin Cases ; 10(31): 11652-11657, 2022 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-36387829

RESUMO

BACKGROUND: Colonoscopy has become a routine physical examination as people's health awareness has increased. Polyethylene glycol (PEG) is greatly used in bowel preparation before colonoscopy due to its price and safety advantages. Septic shock after colonoscopy with PEG preparation is extremely rare, with only very few cases in critically ill patients. Herein, we describe a case of septic shock in a healthy young adult immediately following colonoscopy with PEG preparation. CASE SUMMARY: A 33-year-old young adult presented to our hospital for colonoscopy with PEG bowel preparation due to recurrent diarrhea for 7 years. The male's previous physical examination showed no abnormal indicators, and colonoscopy results were normal; however, he exhibited septic shock and markedly elevated white blood cell, C-reactive protein, and procalcitonin levels on the second day after colonoscopy. Immediate resuscitation and intensive care with appropriate antibiotics improved his condition. However, the blood and stool cultures did not detect the pathogen. CONCLUSION: Septic shock after colonoscopy is rare, especially in young adults. The authors considered the possibility of opportunistic infections after PEG bowel preparation, and clinicians should monitor patients for the possibility of such complications.

12.
Front Immunol ; 13: 1021634, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36189262

RESUMO

Myeloid-derived suppressor cells (MDSCs) are a group of bone marrow derived heterogeneous cells, which is known for their immunosuppressive functions especially in tumors. Recently, MDSCs have receiving increasing attention in pathological conditions like infection, inflammation and autoimmune diseases. Inflammatory bowel diseases (IBD) are a series of immune-dysfunctional autoimmune diseases characterized by relapsing intestinal inflammation. The role of MDSCs in IBD remains controversial. Although most studies in vitro demonstrated its anti-inflammatory effects by inhibiting the proliferation and function of T cells, it was reported that MDSCs failed to relieve inflammation but even promoted inflammatory responses in experimental IBD. Here we summarize recent insights into the role of MDSCs in the development of IBD and the potential of MDSCs-targeted therapy.


Assuntos
Doenças Autoimunes , Doenças Inflamatórias Intestinais , Células Supressoras Mieloides , Anti-Inflamatórios , Doenças Autoimunes/patologia , Humanos , Inflamação
13.
Huan Jing Ke Xue ; 43(9): 4522-4531, 2022 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-36096593

RESUMO

Forty-eight surface water samples were analyzed using ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) in order to study the pollution characteristics and source apportionment of per- and polyfluoroalkylated substances (PFASs) in the Tuojiang River. The results showed that ΣPFASs in the Tuojiang River ranged from 12.5-3789 ng·L-1, and perfluorooctanoic acid (PFOA) was the predominant PFAS, with a concentration of 9.97-3764 ng·L-1 (73.6%-99.8%), suggesting that legacy PFASs were still the dominant PFASs in the Tuojiang River. The most frequently detected emerging PFASs was 9-chlorohexadecafluoro-3-oxanonane-1-sulfonate (F-53B), with a detection frequency of 100%, suggesting the wide use of F-53B in the Tuojiang River. Sodium 1H, 1H, 2H, 2H-perfluorooctane sulfonate (6:2 FTS) displayed the highest concentration among all emerging PFASs[nd-27.3 ng·L-1, mean:(9.12±7.70) ng·L-1], and the concentrations were at the higher levels compared to those in other rivers around the world. In addition, ΣPFASs showed the highest concentrations of ΣPFASs at the fluorochemical manufacturing park (FMP), followed by those in the Luzhou section (in the lower reaches of the Tuojiang River), indicating that the emission of FMP and human daily production activities were the main influencing factors of PFASs pollution in the Tuojiang River. The estimated flux of PFASs from the Tuojiang River to the Yangtze River was 353 kg·a-1, and PFOA displayed the greatest mass loading (348 kg·a-1), which could provide the basic data for controlling PFASs in the Tuojiang River.


Assuntos
Fluorocarbonos , Poluentes Químicos da Água , Cromatografia Líquida , Monitoramento Ambiental , Fluorocarbonos/análise , Humanos , Rios/química , Espectrometria de Massas em Tandem , Poluentes Químicos da Água/análise
14.
Inorg Chem ; 61(30): 11932-11938, 2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35848216

RESUMO

The properties of supports have a significant effect on the activity of noble metal single atoms. In this work, Co-doped CeO2-supported single-atom Pt catalysts (Pt1/Co-CeO2) have been acquired by a synchronous pyrolysis/deposition route and demonstrated to promote low-temperature oxidation of CO. Revealed by a model reaction of 1% CO + 1% O2 + 98% He at a space velocity of 12,000 mL/gcat/h, CO conversion (100 °C) acquired on a (0.5% Pt)/(10% Co-CeO2) catalyst (36.6%) was 3.6 and 4.9 times those of 0.5% Pt/CeO2 (10.0%) and 10% Co-CeO2 (7.4%) catalysts and 2.1 times that of their conversion sum (17.4%), confirming the positive role of the Co dopant in boosting the low-temperature oxidation of CO. The consistent results are also verified in the comparison of Pt1/Co-ZnO with Pt1/ZnO and Pt1/Co-Al2O3 with Pt1/Al2O3. In addition, the activity of single-atom Pt1/Co-CeO2 catalysts can be facilely modified by changing the loading of Pt and/or doping amount of Co. These reasonable data will provide a methodology to access more applicable catalysts for CO oxidation at low temperature.

15.
Environ Sci Pollut Res Int ; 29(17): 25892-25901, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34850344

RESUMO

Effluent from wastewater treatment plants (WWTP) is an important source of organophosphate esters (OPEs) in the receiving rivers. In this paper, the concentration and distribution of seven OPEs in the water samples were determined, and the discharge was estimated. The results showed that the total removal rate of Σ7OPEs in water phase in WWTP was 57.2%. The average concentrations of Σ7OPEs in influent and effluent of the WWTP during rainy period were 3956.1 ± 1897.3 ng/L and 1461.9 ± 846.3 ng/L, respectively, which were about 4 times larger than those in influent water (978.2 ± 166.5 ng/L) and effluent (418.3 ± 12.0 ng/L) during non-rainy period, indicating that rainfall has a marked impact on the load of OPEs in WWTP and the receiving water. It was estimated that the average daily discharge of Σ7OPEs in the effluent of WWTP was 157.9 g, and the daily per capita contribution of the population in the area to the OPEs in the influent was 0.414 mg. During the shift of labour-intensive manufacturing from the coastal developed areas to inland regions, OPEs were widely used and produced in Southwest China. The total amount of OPEs emissions and its control should be taken into consideration.


Assuntos
Retardadores de Chama , Poluentes Químicos da Água , Purificação da Água , China , Monitoramento Ambiental/métodos , Ésteres , Retardadores de Chama/análise , Organofosfatos , Águas Residuárias , Água , Poluentes Químicos da Água/análise
16.
Arch Environ Contam Toxicol ; 82(1): 11-20, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34709437

RESUMO

Human activities have led to the release of organophosphate esters (OPEs) into the environment. This study aims to investigate the levels and partitioning of OPEs in surface water, suspended particulate matter (SPM) and sediments of landscape waters across eleven parks in the city of Chengdu, a megacity in Southwest China. The average concentration of Σ6OPEs in the SPM samples (median: 2.94 × 103 ng/L, 6.88 × 104 ng/g dry weight) was 1-3 orders of magnitude higher than that in the surface water (median: 359 ng/L) and sediment (median: 82.8 ng/g) samples. Tri-n-butyl phosphate (TnBP), tris-(2-chloroethyl)-phosphate (TCEP) and trichloropropyl phosphate (TCIPP) were the primary OPE pollutants in the surface water and SPM samples, while TnBP, tris-(2-butoxyethyl) phosphate (TBEP) and tris-(2-ethylhexyl) phosphate (TEHP) predominated the sediment samples. The higher log Koc values of OPEs in park landscape water bodies estimated in the present study relative to previous studies could be explained by the environmental conditions, such as the sources of the inputs and the hydraulic retention times in these surface waters.


Assuntos
Retardadores de Chama , China , Monitoramento Ambiental , Ésteres , Retardadores de Chama/análise , Humanos , Organofosfatos , Água , Áreas Alagadas
17.
Nat Prod Res ; 36(18): 4605-4613, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34736358

RESUMO

Four new depsidones, mollicellins V-Y (1-4), together with eight known depsidones (5-12) were isolated from the endophytic fungus, Chaetomium brasiliense, detached from stems of Thai rice. Their structures were determined by extensive spectroscopic methods. Mollicellins X, H, and F (3, 8 and 10) showed potent cytotoxicity against the human oral epidermoid carcinoma (KB) cell line, and mollicellin F (10) also showed a potent cytotoxicity against the human hepatocellular carcinoma (HepG2) cell line. Besides, mollicellin B (11) exhibited cytotoxicity against the colorectal adenocarcinoma (HT-29) cell line. Moreover, most of the isolated depsidones displayed potent antibacterial activity against Gram-positive bacteria, Bacillus cereus and Bacillus subtilis, and several of them showed moderate activity against Methicillin-resistant Staphylococcus aureus (MRSA) and clinical isolates of S. aureus. In addition, a few of them also showed moderate activity against a Gram-negative bacteria Pseudomonas aeruginosa.


Assuntos
Antineoplásicos , Chaetomium , Staphylococcus aureus Resistente à Meticilina , Oryza , Antibacterianos/química , Antineoplásicos/química , Chaetomium/química , Depsídeos , Humanos , Lactonas , Testes de Sensibilidade Microbiana , Estrutura Molecular , Sordariales , Staphylococcus aureus , Tailândia
18.
Plant Physiol ; 188(3): 1496-1506, 2022 03 04.
Artigo em Inglês | MEDLINE | ID: mdl-34893909

RESUMO

Tanshinone ⅡA (TⅡA), a diterpene quinone with a furan ring, is a bioactive compound found in the medicinal herb redroot sage (Salvia miltiorrhiza Bunge), in which both furan and dihydrofuran analogs are present in abundance. Progress has been made recently in elucidating the tanshinone biosynthetic pathway, including heterocyclization of the dihydrofuran D-ring by cytochrome P450s; however, dehydrogenation of dihydrofuran to furan, a key step of furan ring formation, remains uncharacterized. Here, by differential transcriptome mining, we identified six 2-oxoglutarate-dependent dioxygenase (2-ODD) genes whose expressions corresponded to tanshinone biosynthesis. We showed that Sm2-ODD14 acts as a dehydrogenase catalyzing the furan ring aromatization. In vitro Sm2-ODD14 converted cryptotanshinone to TⅡA and thus was designated TⅡA synthase (SmTⅡAS). Furthermore, SmTⅡAS showed a strict substrate specificity, and repression of SmTⅡAS expression in hairy root by RNAi led to increased accumulation of total dihydrofuran-tanshinones and decreased production of furan-tanshinones. We conclude that SmTⅡAS controls the metabolite flux from dihydrofuran- to furan-tanshinones, which influences medicinal properties of S. miltiorrhiza.


Assuntos
Dioxigenases/genética , Dioxigenases/metabolismo , Diterpenos/metabolismo , Furanos/metabolismo , Plantas Medicinais/metabolismo , Salvia miltiorrhiza/genética , Salvia miltiorrhiza/metabolismo , Vias Biossintéticas , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Raízes de Plantas/metabolismo
19.
Metab Eng ; 68: 86-93, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34555495

RESUMO

Coenzyme Q (CoQ) is vital for energy metabolism in living organisms. In humans, CoQ10 deficiency causes diseases and must be replenished via diet; however, CoQ content in plant foods is primarily low. Here, we report the breeding of high CoQ10 tomato lines by expressing four enzymes with a fruit-specific promoter, which modifies the chloroplast chorismate pathway, enhances cytosolic isoprenoid biosynthesis, and up-regulates the first two reactions in mitochondrion that construct the CoQ10 polyisoprenoid tail. We show that, while the level of the aromatic precursor could be markedly elevated, head group prenylation is the key to increasing the final CoQ10 yield. In the HUCD lines expressing all four transgenes, the highest CoQ10 content (0.15 mg/g dry weight) shows a seven-fold increase from the wild-type level and reaches an extraordinarily rich CoQ10 food grade. Overviewing the changes in other terpenoids by transcriptome and metabolic analyses reveals variable contents of carotenoids and α-tocopherol in the HUCD lines. In addition to the enigmatic relations among different terpenoid pathways, high CoQ10 plants maintaining substantial levels of either vitamin can be selected. Our investigation paves the way for the development of CoQ10-enriched crops as dietary supplements.


Assuntos
Solanum lycopersicum , Ubiquinona , Carotenoides/metabolismo , Frutas/metabolismo , Humanos , Solanum lycopersicum/genética , Mitocôndrias , Ubiquinona/genética
20.
ACS Omega ; 6(10): 6914-6923, 2021 Mar 16.
Artigo em Inglês | MEDLINE | ID: mdl-33748605

RESUMO

A type of carbon molecular sieve (CMS-3KT) was used as the adsorbent for the CH4 enrichment of a methane/oxygen/nitrogen (CH4/O2/N2) mixture using micro-positive pressure vacuum pressure swing adsorption (∼120 kPa). The adsorption isotherms of individual CH4, O2, and N2 on CMS-3KT were studied and fitted. The results indicated the important influence of the adsorbent surface heterogeneity on the adsorption equilibrium process. In addition, the interaction of adsorbent-adsorbate in this process was studied from the measured adsorption heat. The adsorption uptake curves were fitted linearly with a classical micropore model for evaluating the kinetics-based separation possibility of CH4/O2/N2, and the corresponding diffusion time constants of CH4, O2, and N2 were calculated. Based on the results of adsorption equilibrium and kinetics, breakthrough experiments were employed to explore the upper limit value of methane concentration in feed gas such that methane can be enriched feasibly but difficultly. The breakthrough experiments were performed on the CH4/O2/N2 mixture with CH4 concentration ranging from 1 to 30%. Regarding industrial application, the O2 removal and CH4 enrichment performance of ultra-low-concentration methane (CH4 < 5%) were evaluated according to the results of the breakthrough experiment. The results indicated that the proposed method was promising for enriching O2-containing ultra-low-concentration CBM.

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