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1.
Int Microbiol ; 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35925494

RESUMO

The NADPH-regeneration enzymes in Corynebacterium glutamicum were inactivated to construct an NADPH-auxotrophic C. glutamicum strain by gene knockout and gene replacement. The resultant NADPH-auxotrophic C. glutamicum XL-1 ΔZMICg::ISm (i.e., strain Leu-1) grew well in the basic medium only with gluconate as carbon source. Replacement of the native glyceraldehyde 3-phosphate dehydrogenase (NAD-GapDHCg) by NADP-GapDHCa from Clostridium acetobutylicum is an effective strategy for producing L-leucine in NADPH-prototrophic strain XL-1 and NADPH-auxotrophic strain Leu-1, whereas the L-leucine yield did not differ significantly between these strains (14.1 ± 1.8 g/L vs 16.2 ± 1.1 g/L). Enhancing the carbon flux in biosynthetic pathway by recombinant expression plasmid pEC-ABNCE promoted L-leucine production, but the shortage NADPH supply limited the L-leucine yield. The mutated promoters of zwf and icdCg were introduced into C. glutamicum with NADP-GapDHCa and pEC-ABNCE increased L-leucine yield (54.3 ± 2.9 g/L) and improved cell growth (OD562 = 83.4 ± 7.5) in fed-batch fermentation because the resultant strain C. glutamicum XL-1 ΔMICg::ISm GCg::GCa Pzwf-D1 Picd-D2/pEC-ABNCE (i.e., strain Leu-9) exhibited the proper intracellular NADPH and NADH level. This is the first report of constructing an L-leucine high-yielding strain that reasonably supplies NADPH by optimizing the biosynthetic pathway of NADPH from an NADPH-auxotrophic strain.

2.
J Med Chem ; 2022 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-35925880

RESUMO

Aberrant hyperactivation of cyclins results in carcinogenesis and therapy resistance in cancers. Direct degradation of the specific cyclin or cyclin-dependent kinase (CDK)-cyclin complex by small-molecule degraders remains a great challenge. Here, we applied the first application of hydrophobic tagging to induce degradation of CDK9-cyclin T1 heterodimer, which is required to keep productive transcription of oncogenes in cancers. LL-K9-3 was identified as a potent small-molecule degrader of CDK9-cyclin T1. Quantitative and time-resolved proteome profiling exhibited LL-K9-3 induced selective and synchronous degradation of CDK9 and cyclin T1. The expressions of androgen receptor (AR) and cMyc were reduced by LL-K9-3 in 22RV1 cells. LL-K9-3 exhibited enhanced anti-proliferative and pro-apoptotic effects compared with its parental CDK9 inhibitor SNS032 and suppressed downstream signaling of CDK9 and AR more effectively than SNS032. Moreover, LL-K9-3 inhibited AR and Myc-driven oncogenic transcriptional programs and exerted stronger inhibitory effects on several intrinsic target genes of AR than the monomeric CDK9 PROTAC (Thal-SNS032).

3.
J Environ Sci (China) ; 119: 23-32, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35934462

RESUMO

Co-pyrolysis of coal and seaweed can not only effectively decrease the carbon footprint but also improve the quality and output of coal pyrolysis products, however, the influence of seaweed on thermal releasing behaviors of mercury during co-pyrolysis process are still unclear. In this work, the chlorella and Guizhou bituminous coal were mixed and used to reveal the mercury release behavior during co-pyrolysis by the temperature programmed pyrolysis experiments, thermogravimetric and differential thermogravimetric analysis (TG-DTG) and thermogravimetry-mass spectrometry (TG-MS) methods, offering a sufficient explanation on the control technology of mercury pollutants in co-pyrolysis. The results exhibited that a large amount of reducing gases such as CO, H2 and H2O were generated in chlorella at the temperature range of 100-500°C, which was favorable for the transformation from oxidized mercury to elemental mercury, thus remarkably increased the release of elemental mercury in the raw coal sample. The mixed chlorella also significantly lowered the decomposition temperature range (from 400-600 to 300-400°C) of pyrite-bound mercury and decreased the decomposition temperatures of the pyrite-bound mercury species. Additionally, in the co-pyrolysis about 91.82% of mercury was released into the gas phase below 400°C and was 13.77% higher than that of in individual pyrolysis of coal.


Assuntos
Chlorella , Mercúrio , Carvão Mineral/análise , Gases , Cinética , Pirólise , Termogravimetria
4.
Front Plant Sci ; 13: 892630, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35937318

RESUMO

Callose synthase plays an essential role in plant growth and development and in response to all sorts of stresses through regulating callose formation. However, few research about the function and mechanism of the insect resistance of callose synthase genes have been reported in cotton. In this study, a cotton callose synthase gene GhCalS5 was cloned, and its function and mechanism of resistance to cotton aphids were analyzed. The expression of GhCalS5 was significantly upregulated in both, leaves and stems of cotton plants at 48 h after cotton aphid infestation and in the leaves of cotton plants at 24 h after salicylic acid treatment. The overexpression of GhCalS5 enhanced cotton resistance to cotton aphids. Expectedly silencing of GhCalS5 reduced cotton resistance to cotton aphids. Overexpression of GhCalS5 enhanced callose formation in cotton leaves. Our results suggest that GhCalS5 is involved in cotton resistance against cotton aphids by influencing callose formation.

5.
Foods ; 11(15)2022 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-35954000

RESUMO

Refining degree has an important influence on the quality of camellia (Camellia oleifera) oil. The deterioration behaviors and lipid oxidation of three kinds of camellia oils, including camellia crude oil (CO), moderate refined oil (MRO), and refined oil (RO), during heating were investigated in this study. The results of deterioration behavior analysis showed that the oxidation degree was RO > CO > MRO. Tocopherol and polyphenolic substances in the oil might help delay oil oxidation. The lipid oxidation results indicated that the heating process had greater effects on CO and MRO than RO; it upregulated neutral lipid content and downregulated phospholipid content in terms of lipid changes and the multiplicity of differences. Glycerophospholipid metabolism was the most remarkable pathway and was important to study the heating process of refined oil. Moderate refining is good for retaining the beneficial lipids in camellia oil. The results of this study would provide a theoretical basis for camellia oil processing.

6.
Nutrients ; 14(15)2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35956324

RESUMO

(1) Background: The management goal for patients with essential hypertension (HTN) is not only to lower blood pressure (BP), but also to control increased heart rate (HR). In a previous study, it was found that dietary fiber (DF) supplementation can effectively reduce BP in patients with HTN. The aim of this study was to determine whether a DF supplement can lower HR in patients with HTN. (2) Methods: Seventy patients who met the inclusion and exclusion criteria were randomly allocated into the control group (n = 34) and the intervention group (n = 36). The regular DASH dietary care was delivered to both groups of patients. In addition, one bag of oat bran (30 g/d, containing DF 8.9 g) was delivered to the intervention group. The 24 h ambulatory heart rate was measured at baseline and 3 months. (3) Results: At 3 months, the 24 h maximum heart rate (24h maxHR) in the intervention group was significantly lower than that in the control group. After the intervention, within-group comparisons in the intervention group revealed that there were significant reductions in the 24 h average heart rate (24h aveHR), 24h maxHR, average heart rate during day time (D-aveHR), minimum heart rate during day time (D-minHR), and maximum heart rate during day time (D-maxHR). Similar differences were not found in the control group. (4) Conclusions: Dietary fiber (oat bran) supplementation might be beneficial in lowering HR in patients with HTN.


Assuntos
Avena , Hipertensão , HDL-Colesterol , Dieta , Fibras na Dieta , Suplementos Nutricionais , Frequência Cardíaca , Humanos , Hipertensão/tratamento farmacológico
7.
Polymers (Basel) ; 14(15)2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35956678

RESUMO

In this study, multifunctional chitosan-pluronic F127 with magnetic reduced graphene oxide (MRGO) nanocomposites were developed through the immobilization of chitosan and an amphiphilic polymer (pluronic F127) onto the MRGO. Physicochemical characterizations and in-vitro cytotoxicity of nanocomposites were investigated through field emission scanning electron microscopy (FESEM), X-ray diffraction (XRD), Fourier-transform infrared (FTIR) spectroscopy, particle size analysis, vibrating sample magnetometer, Raman spectroscopy and resazurin-based in-vitro cytotoxicity assay. FESEM observation shows that the magnetic nanoparticles could tethered on the surface of MRGO, promoting the magnetic properties of the nanocomposites. FTIR identification analysis revealed that the chitosan/pluronic F127 were successfully immobilized on the surface of MRGO. Furthermore, α-mangosteen, as a model of natural drug compound, was successfully encapsulated onto the chitosan/pluronic F127@MRGO nanocomposites. According to in-vitro cytotoxicity assay, α-mangosteen-loaded chitosan/pluronic F127@MRGO nanocomposites could significantly reduce the proliferation of human breast cancer (MFC-7) cells. Eventually, it would be anticipated that the novel α-mangosteen-loaded chitosan/pluronic F127@MRGO nanocomposites could be promoted as a new potential material for magnetically targeting and killing cancer cells.

8.
Am J Transl Res ; 14(7): 5187-5194, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958443

RESUMO

OBJECTIVE: To explore the difference in anxiety and mental health of patients with liver cirrhosis with different compensatory abilities, so as to provide comprehensive treatment measures such as individualized psychological support for patients. METHODS: In this retrospective study, a total of 175 patients with liver cirrhosis admitted to the Department of Infectious Diseases, Fifth Hospital of Sun Yat-sen University from January to December 2019 were included and divided into a compensated group (n=77) and a decompensated group (n=98). The anxiety of patients was evaluated on the day of admission, one week after hospitalization, and the day of discharge using the Self-Rating Anxiety Scale (SAS). Psychological investigations were conducted on the two groups of patients with cirrhosis. RESULTS: The SAS score of patients in the decompensated group was higher than that of the compensated group on the day of admission (48.62±6.35 vs. 37.68±8.94, F=20.313), one week after hospitalization (56.95±7.47 vs. 42.79±10.77, F=29.879), and on the day of discharge (42.95±7.85 vs. 36.43±9.29, F=7.110) (P<0.05). The SAS score of male patients in the decompensated group was higher than that of the compensated group on the day of admission (47.50±6.25 vs. 36.70±9.92, t=-4.112), one week after hospitalization (57.25±5.80 vs. 42.10±13.24, t=-4.538) and on the day of discharge (42.33±7.34 vs. 36.19±9.65, t=-2.162) (all P<0.05). The SAS score of 40-59 year-old patients of the decompensated group was higher than that of patients in the compensated group of the same age on the day of admission (51.80±6.26 vs. 36.84±8.57, t=-4.372), one week after hospitalization (60.6±7.06 vs. 42.94±10.33, t=-4.382), and on the day of discharge (48.60±4.16 vs. 37.32±10.23, t=-3.768) (P<0.05). The SAS score of female patients in the decompensated group was higher than that in the compensated group at one week after hospitalization (56.56±9.65 vs. 35.45±18.66, t=-4.617) (P<0.05). There was no difference in the SAS score between patients of different groups on the day of admission and the day of discharge (P>0.05). CONCLUSION: The anxiety of patients with different compensatory abilities of the liver is adversely affected by the severity of their illness and the length of hospitalization. The anxiety of male patients in the decompensated group is more significant than that of patients in the compensated group, while no significant difference was observed in anxiety between female patients in the decompensated group and those in the compensated group on the day of admission and discharge. It is necessary to strengthen psychological intervention, optimize the treatment methods, and reduce the average hospital stay in decompensated patients.

9.
Front Aging Neurosci ; 14: 936024, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35959294

RESUMO

Background: Depression is common and serious among elderly patients. The treatment of elderly depression is often delayed owing to insufficient diagnosis, which eventually leads to adverse consequences. Aims: To explore the association between the parameters of the Comprehensive Geriatric Assessment and depression in elderly patients. Methods: A cross-sectional study of 211 outpatients and inpatients aged ≥ 65 years from the Comprehensive Geriatric Assessment database was conducted. A Comprehensive Geriatric Assessment inventory was prepared by compiling and screening general characteristics, chronic diseases (cardiovascular disease, diabetes, and peptic ulcer disease), nutritional status, daily living ability, anthropometric measurements (body mass index (BMI), upper arm circumference, and calf circumference), and blood biochemical indicators (hemoglobin, albumin, prealbumin, triglycerides, and low-density lipoprotein cholesterol). The Geriatric Depression Scale was also conducted for each elderly patient to screen for depression. A multivariable logistic regression analysis was used to determine the association between the parameters of the Comprehensive Geriatric Assessment and geriatric depression. Results: There were 63 patients in the depression group with a median age of 84.00 years, and 148 patients in the non-depression group with a median age of 78.50 years. After controlling for confounders, the risk of depression in elderly patients with cardiovascular diseases was 6.011 times higher than that in those without cardiovascular diseases (p < 0.001); and the risk of depression in elderly patients with peptic ulcer diseases was 4.352 times higher than that in those without peptic ulcer diseases (p < 0.001); the risk of depression in elderly patients decreased by 22.6% for each 1-point increase in the Mini Nutritional Assessment (p < 0.001). The risk of depression in elderly patients decreased by 19.9% for each 1-point increase in calf circumference (p = 0.002), and by 13.0% for each 1-point increase in albumin (p = 0.014). Conclusion: Our findings suggest that Comprehensive Geriatric Assessment parameters, such as cardiovascular disease, peptic ulcer disease, Mini Nutritional Assessment score, calf circumference, and albumin, were associated with depression. The Comprehensive Geriatric Assessment can assist in the early identification of depression in the elderly population.

10.
Nurs Open ; 2022 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-35964290

RESUMO

AIM: The aim of this study was to explore the mediating role of perceived social support in the association between perceived stress and job burnout in midwives. DESIGN: A descriptive, cross-sectional online survey. METHODS: Using the stratified cluster sampling method, 329 midwives in 20 hospitals in China were selected as the participants. They completed self-report assessment measures of job burnout, perceived stress and perceived social support. RESULTS: 63.5% of the participants had job burnout. Perceived stress was negatively associated with social support (r = -.350, p < .01), while it was positively associated with job burnout (r = -.382, p < .01). Social support was negatively correlated with job burnout (r = -.569, p < .01). The total effect of perceived stress on job burnout was 0.474 (95% CI: 0.367 ~ 0.596, p < .01), the direct effect was 0.242 (95% CI: 0.142 ~ 0.355, p < .01), and the indirect effect was 0.232 (95% CI: 0.160 ~ 0.316, p < .01). Social support programmes for midwives should be implemented to control the impact of perceived stress on job burnout.

11.
Biomed Res Int ; 2022: 7728973, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35958822

RESUMO

Background: As a traditional Chinese exercise, Qigong has potential benefits for the management of chronic obstructive pulmonary disease (COPD). This overview is aimed at assessing the existing evidence for the intervention of Qigong in COPD so as to provide scientific guidance for clinical decision-making. Methods: The systematic reviews (SRs)/meta-analyses (MAs) of Qigong for the treatment of COPD were obtained from 7 electronic databases with the search date set at April 5, 2022. Two researchers independently assessed the methodological quality, reporting quality, and evidence quality for the included SRs/MAs using the following tools: the Assessment of Multiple Systematic Reviews 2 (AMSTAR-2), the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 (PRISMA 2020), and the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) system. Results: A total of 13 SRs/MAs were included in this overview. All SRs/MAs assessed by AMSTAR-2 had more than one critical defect, so all SR/MAs were rated very low. Regarding the assessment of reporting quality, the results of PRISMA 2020 showed that none of the SRs/MAs were fully reported. In addition, the results of the GRADE assessment of the quality of evidence indicated that only 3 outcomes were rated as high quality across all SRs/MAs. Conclusion: Current evidence suggests that Qigong is effective and safe for the management of patients with COPD. However, the high risk of bias in the original clinical studies and the low quality of the SRs/MAs reduced the reliability of the results.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Qigong , China , Humanos , Doença Pulmonar Obstrutiva Crônica/terapia , Reprodutibilidade dos Testes , Relatório de Pesquisa
12.
Cell Mol Immunol ; 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35970871

RESUMO

Pyroptosis is a form of programmed cell death mediated by gasdermin and is a product of continuous cell expansion until the cytomembrane ruptures, resulting in the release of cellular contents that can activate strong inflammatory and immune responses. Pyroptosis, an innate immune response, can be triggered by the activation of inflammasomes by various influencing factors. Activation of these inflammasomes can induce the maturation of caspase-1 or caspase-4/5/11, both of which cleave gasdermin D to release its N-terminal domain, which can bind membrane lipids and perforate the cell membrane. Here, we review the latest advancements in research on the mechanisms of pyroptosis, newly discovered influencing factors, antitumoral properties, and applications in various diseases. Moreover, this review also provides updates on potential targeted therapies for inflammation and cancers, methods for clinical prevention, and finally challenges and future directions in the field.

14.
Mol Pharm ; 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35971845

RESUMO

In recent years, piperlongumine (PL) having specific cytotoxicity has attracted considerable attention for anticancer activity. Through structural modification, the active derivative PL 1-3 shows potential anti-inflammatory activity and low cytotoxicity, but its water solubility is low. Here, PL 1-3-loaded bovine serum albumin nanoparticles (1-3 NPs) were prepared and characterized, which can improve the dissolution. 1-3 NPs exhibited effective hepatoprotective effects on lipopolysaccharide/d-galactosamine-induced acute liver injury of mice, which was similar to liver injury in clinical settings. 1-3 NPs treatment can inhibit inflammation, oxidative stress, and apoptosis via the downregulation of NF-κB signaling pathways, the activation of Nrf2/HO-1 signaling pathways, and the inhibition of expression of Bax and caspase 3 proteins. The above results demonstrated that PL 1-3-loaded bovine serum albumin nanoparticles possessed potential value in intervention of inflammation-based liver injury.

15.
Front Endocrinol (Lausanne) ; 13: 907973, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35909552

RESUMO

Background: It has been proved that triglyceride glucose-body mass index (TyG-BMI) is a readily available and clinically significant indicator of insulin resistance (IR). Nevertheless, the association between TyG-BMI and incident Type 2 diabetes mellitus (T2DM) remains uncertain. This study aimed to study the relationship between TyG-BMI and T2DM and explore the predictive characteristics of TyG-BMI. Methods: Our study was conducted as a longitudinal cohort study. 8,430 men and 7,034 women were enrolled and analyzed. They were both non-diabetic subjects with normal glycemic levels. Follow-up lasted for 13 years, from 1994 to 2016. To make the number of TyG-BMI in each group similar, the subjects were divided into four groups with 3866 subjects in each group. Results: During the 13-year follow-up period, 373 subjects were diagnosed with incident T2DM. Our multivariate Cox regression analysis revealed that TyG-BMI was an independent predictor of incident T2DM. In addition, our research identified four specific groups, young people (18-44 years old), women, the non-hypertensive population and non-drinkers were at significantly higher risk of developing TyG-BMI-related diabetes (P-interaction< 0.05). The best threshold TyG-BMI for predicting incident T2DM was 197.2987 (area under the curve 0.7738). Conclusions: Our longitudinal cohort study demonstrated the positive correlation between baseline TyG-BMI and risk of incident T2DM in Japanese with normal glycemic levels, and this risk was significantly higher in the young people, women, the non-hypertensive population and non-drinkers.


Assuntos
Diabetes Mellitus Tipo 2 , Adolescente , Adulto , Glicemia/análise , Índice de Massa Corporal , Estudos de Coortes , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/epidemiologia , Diabetes Mellitus Tipo 2/etiologia , Feminino , Glucose , Humanos , Japão/epidemiologia , Estudos Longitudinais , Masculino , Fatores de Risco , Triglicerídeos , Adulto Jovem
16.
Transl Anim Sci ; 6(3): txac092, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35912064

RESUMO

Our objective was to evaluate the inclusion of calcium-magnesium carbonate [CaMg(CO3)2] and calcium-magnesium hydroxide [CaMg(OH)4] in corn silage-based diets and their impact on ruminal microbiome. Our previous work showed a lower pH and molar proportion of butyrate from diets supplemented with [CaMg(CO3)2] compared to [CaMg(OH)4]; therefore, we hypothesized that ruminal microbiome would be affected by Mg source. Four continuous culture fermenters were arranged in a 4 × 4 Latin square with the following treatments defined by the supplemental source of Mg: 1) Control (100% MgO, plus sodium sesquicarbonate as a buffer); 2) CO 3 [100% CaMg(CO3)2]; 3) OH [100% CaMg(OH)4]; and 4) CO 3 /OH [50% Mg from CaMg(CO3)2, 50% Mg from CaMg(OH)4]. Diet nutrient concentration was held constant across treatments (16% CP, 30% NDF, 1.66 MCal NEl/kg, 0.67% Ca, and 0.25% Mg). We conducted four fermentation periods of 10 d, with the last 3 d for collection of samples of solid and liquid digesta effluents for DNA extraction. Overall, 16 solid and 16 liquid samples were analyzed by amplification of the V4 variable region of bacterial 16S rRNA. Data were analyzed with R and SAS to determine treatment effects on taxa relative abundance of liquid and solid fractions. Correlation of butyrate molar proportion with taxa relative abundance was also analyzed. Treatments did not affect alpha and beta diversities or relative abundance of phylum, class and order in either liquid or solid fractions. At the family level, relative abundance of Lachnospiraceae in solid fraction was lower for CO3 and CO3/OH compared to OH and Control (P < 0.01). For genera, abundance of Butyrivibrio (P = 0.01) and Lachnospiraceae ND3007 (P < 0.01) (both from Lachnospiraceae family) was lower and unclassified Ruminococcaceae (P = 0.03) was greater in CO3 than Control and OH in solid fraction; while abundance of Pseudobutyrivibrio (P = 0.10) and Lachnospiraceae FD2005 (P = 0.09) (both from Lachnospiraceae family) and Ruminobacter (P = 0.09) tended to decrease in CO3 compared to Control in liquid fraction. Butyrate molar proportion was negatively correlated to Ruminococcaceae (r = -0.55) in solid fraction and positively correlated to Pseudobutyrivibrio (r = 0.61) and Lachnospiraceae FD2005 (r = 0.61) in liquid. Our results indicate that source of Mg has an impact on bacterial taxa associated with ruminal butyrate synthesis, which is important for epithelial health and fatty acid synthesis.

17.
Clin Cosmet Investig Dermatol ; 15: 1611-1614, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35975195

RESUMO

Immune-related adverse events have been reported in relation to programmed cell death protein-1 (PD-1). However, there are few reports on PD-1 inhibitor-induced bullous pemphigoid. We report the case of a patient who developed bullous pemphigoid following long-term administration of sintilimab for renal cell carcinoma. He developed scattered erythema, blisters, and generalized pruritus for 1 week before admission. Histopathology showed subepidermal blisters and direct immunofluorescence showed linear deposition of immunoglobulin G and complement 3 on the basement membrane; the level of BP180 was 146.93U/mL. A regimen containing methylprednisolone, minocycline, and niacinamide was administered and the patient was discharged following resolution of symptoms.

18.
J Am Chem Soc ; 2022 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-35975916

RESUMO

"Spin" has been recently reported as an important degree of electronic freedom to improve the performance of electrocatalysts and photocatalysts. This work demonstrates the manipulations of spin-polarized electrons in CsPbBr3 halide perovskite nanoplates (NPLs) to boost the photocatalytic CO2 reduction reaction (CO2RR) efficiencies by doping manganese cations (Mn2+) and applying an external magnetic field. Mn-doped CsPbBr3 (Mn-CsPbBr3) NPLs exhibit an outstanding photocatalytic CO2RR compared to pristine CsPbBr3 NPLs due to creating spin-polarized electrons after Mn doping. Notably, the photocatalytic CO2RR of Mn-CsPbBr3 NPLs is significantly enhanced by applying an external magnetic field. Mn-CsPbBr3 NPLs exhibit 5.7 times improved performance of photocatalytic CO2RR under a magnetic field of 300 mT with a permanent magnet compared to pristine CsPbBr3 NPLs. The corresponding mechanism is systematically investigated by magnetic circular dichroism spectroscopy, ultrafast transient absorption spectroscopy, and density functional theory simulation. The origin of enhanced photocatalytic CO2RR efficiencies of Mn-CsPbBr3 NPLs is due to the increased number of spin-polarized photoexcited carriers by synergistic doping of the magnetic elements and applying a magnetic field, resulting in prolonged carrier lifetime and suppressed charge recombination. Our result shows that manipulating spin-polarized electrons in photocatalytic semiconductors provides an effective strategy to boost photocatalytic CO2RR efficiencies.

19.
Int Immunopharmacol ; 111: 108806, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35914447

RESUMO

Lung cancer is a leading cause of tumor-associated death worldwide. Autophagy plays a key role in regulating lung cancer progression, and is a promising option for lung cancer treatment. Saponins are a group of naturally occurring plant glycosides, characterized by their strong foam-forming properties in aqueous solution, and exert various biological properties, such as anti-inflammation and anti-cancer. In the present study, we for the first time explored the effects of gitogenin (GIT), an important saponin derived from Tribulus longipetalus, on lung cancer progression both in vitro and in vivo. We found that GIT markedly reduced the proliferation and induced apoptosis in lung cancer cells through increasing the cleavage of Caspase-3 and poly (ADP-ribose) polymerases (PARPs). In addition, GIT-incubated lung cancer cells exhibited clear accumulation of autophagosome, which was essential for GIT-suppressed lung cancer. Mechanistically, GIT-induced autophagy initiation was mainly through activating AMP-activated protein kinase (AMPK) and blocking protein kinase B (AKT) signaling pathways, respectively. Moreover, the autophagic flux was disrupted in GIT-treated lung cancer cells, contributing to the accumulation of impaired autophagolysosomes. Importantly, we found that suppressing autophagy initiation could abolish GIT-induced cell death; however, autophagosomes accumulation sensitized lung cancer cells to cell death upon GIT treatment. More in vitro experiments showed that GIT led to reactive oxygen species (ROS) production in lung cancer cells, which was also involved in the modulation of apoptosis. The in vivo findings confirmed the effects of GIT against lung cancer progression with undetectable toxicity to organs. In conclusion, we provided new insights into the treatment of lung cancer, and GIT might be an effective strategy for future clinical application.

20.
Chem Biol Interact ; 365: 110047, 2022 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-35917946

RESUMO

Pyrrolizidine alkaloids (PAs) are among the most significant hepatotoxins widely distributed in plant species. Incidence of liver injuries caused by PAs has been reported worldwide, and the reactive metabolites of PAs are known to play a critical role in causing the hepatotoxicity. To better understand the toxicity-induction mechanisms, we explored the interactions of PA metabolites with cellular RNA molecules, and examined their effects on the biochemical and metabolic properties of hepatic RNAs. After exposure to retrorsine, adduction on adenosine and guanosine were detected in mouse liver microsomal incubations, cultured mouse primary hepatocytes, and mouse liver tissues. NMR analysis showed that the exocyclic amino group participated in the adduction. We found drastically altered properties and metabolism of the adducted RNA such as reverse-transcriptability, translatability, and RNase-susceptibility. In addition, endogenous modification of N6-methyladenosine (m6A) was remarkably reduced.

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