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1.
EMBO Rep ; 25(4): 2015-2044, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38480845

RESUMO

Naive human embryonic stem cells (hESCs) that resemble the pre-implantation epiblasts are fueled by a combination of aerobic glycolysis and oxidative phosphorylation, but their mitochondrial regulators are poorly understood. Here we report that, proline dehydrogenase (PRODH), a mitochondria-localized proline metabolism enzyme, is dramatically upregulated in naive hESCs compared to their primed counterparts. The upregulation of PRODH is induced by a reduction in c-Myc expression that is dependent on PD0325901, a MEK inhibitor routinely present in naive hESC culture media. PRODH knockdown in naive hESCs significantly promoted mitochondrial oxidative phosphorylation (mtOXPHOS) and reactive oxygen species (ROS) production that triggered autophagy, DNA damage, and apoptosis. Remarkably, MitoQ, a mitochondria-targeted antioxidant, effectively restored the pluripotency and proliferation of PRODH-knockdown naive hESCs, indicating that PRODH maintains naive pluripotency by preventing excessive ROS production. Concomitantly, PRODH knockdown significantly slowed down the proteolytic degradation of multiple key mitochondrial electron transport chain complex proteins. Thus, we revealed a crucial role of PRODH in limiting mtOXPHOS and ROS production, and thereby safeguarding naive pluripotency of hESCs.


Assuntos
Fosforilação Oxidativa , Prolina Oxidase , Humanos , Espécies Reativas de Oxigênio/metabolismo , Prolina Oxidase/genética , Prolina Oxidase/metabolismo , Mitocôndrias/metabolismo , Apoptose
2.
Proc Natl Acad Sci U S A ; 119(23): e2118566119, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35648826

RESUMO

Recent work indicates that killing of bacteria by diverse antimicrobial classes can involve reactive oxygen species (ROS), as if a common, self-destructive response to antibiotics occurs. However, the ROS-bacterial death theory has been challenged. To better understand stress-mediated bacterial death, we enriched spontaneous antideath mutants of Escherichia coli that survive treatment by diverse bactericidal agents that include antibiotics, disinfectants, and environmental stressors, without a priori consideration of ROS. The mutants retained bacteriostatic susceptibility, thereby ruling out resistance. Surprisingly, pan-tolerance arose from carbohydrate metabolism deficiencies in ptsI (phosphotransferase) and cyaA (adenyl cyclase); these genes displayed the activity of upstream regulators of a widely shared, stress-mediated death pathway. The antideath effect was reversed by genetic complementation, exogenous cAMP, or a Crp variant that bypasses cAMP binding for activation. Downstream events comprised a metabolic shift from the TCA cycle to glycolysis and to the pentose phosphate pathway, suppression of stress-mediated ATP surges, and reduced accumulation of ROS. These observations reveal how upstream signals from diverse stress-mediated lesions stimulate shared, late-stage, ROS-mediated events. Cultures of these stable, pan-tolerant mutants grew normally and were therefore distinct from tolerance derived from growth defects described previously. Pan-tolerance raises the potential for unrestricted disinfectant use to contribute to antibiotic tolerance and resistance. It also weakens host defenses, because three agents (hypochlorite, hydrogen peroxide, and low pH) affected by pan-tolerance are used by the immune system to fight infections. Understanding and manipulating the PtsI-CyaA-Crp­mediated death process can help better control pathogens and maintain beneficial microbiota during antimicrobial treatment.


Assuntos
Anti-Infecciosos , Colicinas , Proteína Receptora de AMP Cíclico , Proteínas de Escherichia coli , Escherichia coli , Proteínas de Transporte de Monossacarídeos , Estresse Oxidativo , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato , Anti-Infecciosos/farmacologia , Colicinas/metabolismo , AMP Cíclico/metabolismo , Proteína Receptora de AMP Cíclico/metabolismo , Tolerância a Medicamentos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/fisiologia , Proteínas de Escherichia coli/metabolismo , Proteínas de Transporte de Monossacarídeos/metabolismo , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Eur J Clin Microbiol Infect Dis ; 42(2): 129-140, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36445622

RESUMO

The burden of extrapulmonary tuberculosis (EPTB) has gradually increased in recent years, but not enough epidemiological data is available from central Guangxi. To better understand the epidemiology of EPTB in central Guangxi and identify risk factors associated with them, we retrospectively investigated the epidemiology of tuberculosis (TB), especially EPTB, among patients admitted to the Chest Hospital of Guangxi Zhuang Autonomous Region between 2016 and 2021. We excluded those infected with both pulmonary tuberculosis (PTB) and EPTB, reported the proportion and incidence of PTB or EPTB, and compared the demographic characteristics and risk factors of EPTB and PTB cases using univariate and multivariate logistic regression models. Among 30,893 TB patients, 67.25% (20,774) had PTB and 32.75% (10,119) had EPTB. Among EPTB, pleural, skeletal, lymphatic, pericardial, meningeal, genitourinary, intestinal, and peritoneal TB accounted for 49.44%, 27.20%, 8.55%, 4.39%, 3.36%, 1.48%, 0.87%, and 0.79%, respectively. Patients who were younger (age < 25), from rural areas, Zhuang and other ethnic groups, and diagnosed with anemia and HIV infection were more likely to develop EPTB. However, patients with diabetes and COPD were less likely to have EPTB. From 2016 to 2021, the proportion of PTB cases decreased from 69.73 to 64.07%. The percentage of EPTB cases increased from 30.27 to 35.93%, with the largest increase in skeletal TB from 21.48 to 34.13%. The epidemiology and risk factors of EPTB in central Guangxi are different from those of PTB. The incidence of EPTB is increasing and further studies are needed to determine the reasons for it.


Assuntos
Infecções por HIV , Tuberculose Extrapulmonar , Tuberculose Pulmonar , Tuberculose , Humanos , Infecções por HIV/epidemiologia , Estudos Retrospectivos , China/epidemiologia , Tuberculose/epidemiologia , Tuberculose/diagnóstico , Tuberculose Pulmonar/epidemiologia
4.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 45(2): 185-192, 2023 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-37157063

RESUMO

Objective To study the effect and mechanism of pearl hydrolysate on hepatic sinusoidal capillarization in liver fibrosis. Methods Hepatic sinusoidal endothelial cells (HSEC) and hepatic stellate cells (HSC-LX2) were incubated with Hepu pearl hydrolysate.The proliferation of HSEC and HSC-LX2 was examined by MTT colorimetry.The cell cycle and apoptosis of HSC-LX2 were measured by flow cytometry.The changes of the microstructures such as fenestra and basement membrane of HSEC were observed by transmission electron microscopy. Results The intervention with leptin increased the viability of HSC-LX2 (P=0.041),decreased the viability of HSEC (P=0.004),and caused capillarization signs such as decreased number and diameter of fenestrae and formation of continuous basement membrane.The treatment with pearl hydrolysate at different doses increased and expanded the fenestrae of HSEC (low dose:P=0.020;medium dose:P=0.028;high dose:P=0.032),disintegrated the extracellular basement membrane of HSEC (low dose:P=0.020;medium dose:P=0.028;high dose:P=0.032),decreased the viability of HSC-LX2 (low dose:P=0.018;medium dose:P=0.013;high dose:P=0.009),and induced the apoptosis of HSC-LX2 (low dose:P=0.012;medium dose:P=0.006;high dose:P=0.005).Pearl hydrolysate exerted therapeutic effect on capillarization in a dose-dependent manner (low dose:P=0.020;medium dose:P=0.028;high dose:P=0.032).Moreover,high-dose pearl hydrolysate showed stronger effect on capillarization of hepatic sinuses than colchicine (P=0.034) and salvianolic acid B (P=0.038). Conclusion Hepu pearl hydrolysate can increase the viability of HSEC,restore the area of fenestrae,disintegrate the basement membrane,and decrease the viability and induce the apoptosis of HSC-LX2,demonstrating significant pharmacological effects on the capillarization of HSEC and HSC-LX2.


Assuntos
Células Endoteliais , Cirrose Hepática , Humanos , Células Endoteliais/metabolismo , Fígado/patologia
5.
J Am Chem Soc ; 143(29): 11109-11120, 2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34278799

RESUMO

In situ-formed iron carbides (FeCx) are the key components responsible for Fischer-Tropsch synthesis (FTS, CO + H2 → long-chain hydrocarbons) on Fe-based catalysts in industry. The true active site is, however, highly controversial despite more than a century of study, which is largely due to the combined complexity in both FeCx structures and mechanism of CO hydrogenation. Herein powered by machine learning simulation, millions of structure candidates for FeCx bulk and surfaces are explored under FTS conditions, which leads to resolving the active site for CO activation. This is achieved without a priori input from experiment by first constructing the thermodynamics convex hull of bulk phases, followed by identifying the low surface energy surfaces and evaluating the adsorption ability of CO and H, and finally determining the lowest energy reaction pathway of CO activation. Rich information on FeCx structures and CO hydrogenation pathways is gleaned: (i) Fe5C2, Fe7C3, and Fe2C are the three stable bulk phases under FTS in producing olefins, where Fe7C3 and Fe2C have multiple energetically nearly degenerate bulk crystal phases; (ii) only three low surface energy surfaces of these bulk phases, namely, χ-Fe5C2(510), χ-Fe5C2(111), and η-Fe2C(111), expose the Fe sites that can adsorb H atoms exothermically, where the surface Fe:C ratio is 2, 1.75, and 2, respectively; (iii) CO activation via direct dissociation can occur at the surface C vacancies (e.g., with a barrier of 1.1 eV) that are created dynamically via hydrogenation. These atomic-level understandings facilitate the building of the structure-activity correlation and designing better FT catalysts.

6.
Chin J Cancer Res ; 33(2): 243-255, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-34158743

RESUMO

OBJECTIVE: Breast cancer (BC) with chest wall metastasis (CWM) usually shows rich neovascularization. This trial explored the clinical effect of apatinib on human epidermal growth factor receptor 2 (HER2)-negative advanced BC involving CWM. METHODS: This trial involved four centers in China and was conducted from September 2016 to March 2020. Patients received apatinib 500 mg/d [either alone or with endocrine therapy if hormone receptor-positive (HR+)] until disease progression or unacceptable toxicity. Progression-free survival (PFS) was the primary endpoint. RESULTS: We evaluated 26 patients for efficacy. The median PFS (mPFS) and median overall survival (mOS) were 4.9 [range: 2.0-28.5; 95% confidence interval (95% CI): 2.1-8.3] months and 18 (range: 3-55; 95% CI: 12.9-23.1) months, respectively. The objective response rate (ORR) was 42.3% (11/26), and the disease-control rate was 76.9% (20/26). In the subgroup analysis, HR+ patients compared with HR-negative patients had significantly improved mPFS of 7.0 (95% CI: 2.2-11.8) monthsvs. 2.3 (95% CI: 1.2-3.4) months, respectively (P=0.001); and mPFS in patients without or with chest wall radiotherapy was 6.4 (95% CI: 1.6-19.5) monthsvs. 3.0 (95% CI: 1.3-4.6) months, respectively (P=0.041). In the multivariate analysis, HR+ status was the only independent predictive factor for favorable PFS (P=0.014). CONCLUSIONS: Apatinib was highly effective for BC patients with CWM, especially when combined with endocrine therapy. PFS improved significantly in patients with HR+ status who did not receive chest wall radiotherapy. However, adverse events were serious and should be carefully monitored from the beginning of apatinib treatment.

7.
J Cell Mol Med ; 24(18): 10525-10541, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32798252

RESUMO

Hepatocellular carcinoma (HCC) is the third leading cause of the cancer-related death in the world. Human amniotic mesenchymal stem cells (hAMSCs) have been characterized with a pluripotency, low immunogenicity and no tumorigenicity. Especially, the immunosuppressive and anti-inflammatory effects of hAMSCs make them suitable for treating HCC. Here, we reported that hAMSCs administrated by intravenous injection significantly inhibited HCC through suppressing cell proliferation and inducing cell apoptosis in tumour-bearing mice with Hepg2 cells. Cell tracking experiments with GFP-labelled hAMSCs showed that the stem cells possessed the ability of migrating to the tumorigenic sites for suppressing tumour growth. Importantly, both hAMSCs and the conditional media (hAMSC-CM) have the similar antitumour effects in vitro, suggesting that hAMSCs-derived cytokines might be involved in their antitumour effects. Antibody array assay showed that hAMSCs highly expressed dickkopf-3 (DKK-3), dickkopf-1 (DKK-1) and insulin-like growth factor-binding protein 3 (IGFBP-3). Furthermore, the antitumour effects of hAMSCs were further confirmed by applications of the antibodies or the specific siRNAs of DKK-3, DKK-1 and IGFBP-3 in vitro. Mechanically, hAMSCs-derived DKK-3, DKK-1 and IGFBP-3 markedly inhibited cell proliferation and promoted apoptosis of Hepg2 cells through suppressing the Wnt/ß-catenin signalling pathway and IGF-1R-mediated PI3K/AKT signalling pathway, respectively. Taken together, our study demonstrated that hAMSCs possess significant antitumour effects in vivo and in vitro and might provide a novel strategy for HCC treatment clinically.


Assuntos
Âmnio/citologia , Carcinoma Hepatocelular/terapia , Neoplasias Hepáticas/terapia , Transplante de Células-Tronco Mesenquimais , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Proteínas Adaptadoras de Transdução de Sinal/genética , Proteínas Adaptadoras de Transdução de Sinal/fisiologia , Adipogenia , Animais , Apoptose , Carcinoma Hepatocelular/patologia , Feminino , Genes Reporter , Células Hep G2/transplante , Humanos , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/antagonistas & inibidores , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/genética , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/fisiologia , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/fisiologia , Neoplasias Hepáticas/patologia , Masculino , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos NOD , Camundongos Nus , Camundongos SCID , Proteínas de Neoplasias/antagonistas & inibidores , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/fisiologia , Osteogênese , Comunicação Parácrina , Gravidez , Interferência de RNA , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/farmacologia , Transdução de Sinais , Ensaios Antitumorais Modelo de Xenoenxerto
8.
J Sep Sci ; 43(21): 4077-4087, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32860653

RESUMO

Oxathiapiprolin is a chiral fungicide used in China for the prevention and treatment of grape downy mildew, but its potential risk could be inaccurately assessed without distinguishing its enantiomers. In this study, an effective and sensitive chiral analytical method was first established for quantification of oxathiapiprolin enantiomers using supercritical fluid chromatography tandem mass spectrometry. Baseline separation for oxathiapiprolin enantiomers was achieved for less than 3 min by using a Lux Cellulose-2 chiral column with the resolution of 1.51. The elution order of the eluting enantiomers was identified as (-)-oxathiapiprolin and (+)-oxathiapiprolin by an optical rotation detector. The grape samples were extracted by QuEChERS method, with the average recoveries of each enantiomer in grapes were in the range of 88.1-111.8% and the relative standard deviations were less than 18.9%. The enantioselective analysis of the dissipation of oxathiapiprolin in field grape samples showed that (-)-oxathiapiprolin was dissipated faster than (+)-oxathiapiprolin. The results indicate that this proposed method could provide data support for the risk assessment of oxathiapiprolin in agricultural produces in a more accurate way.


Assuntos
Fungicidas Industriais/análise , Hidrocarbonetos Fluorados/análise , Pirazóis/análise , Poluentes do Solo/análise , Vitis/química , Cromatografia com Fluido Supercrítico , Estrutura Molecular , Estereoisomerismo , Espectrometria de Massas em Tandem
9.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 45(2): 155-159, 2020 Feb 28.
Artigo em Inglês, Chinês | MEDLINE | ID: mdl-32386040

RESUMO

OBJECTIVES: To explore the therapeutic effect of myofascial trigger point electroacupuncture technology on treating female overactive bladder syndrome. METHODS: Forty female patients with overactive bladder were randomly divided into 2 groups: an experimental group and a control group. The experimental group was treated with myofascial trigger point electroacupuncture therapy combined with solifenacin succinate while the control group was only treated with solifenacin succinate. Patients in both groups were treated for 12 weeks. The overactive bladder symptom score (OABSS), urinary urgency score and urination frequency of 24 h in the 2 groups were compared to analyze the therapeutic effect. RESULTS: Before the comprehensive treatment, there was no significant difference between the experimental group and the control group (P>0.05). After 2 and 12 weeks of continuous treatment, the OABSS, urinary urgency symptoms score and 24 h urination frequency in the experimental group and the control group were lower than those before the treatment, and the degree of decline in the experimental group was more obvious, with significant difference (P<0.05). CONCLUSIONS: Treating overactive bladder syndrome in women with myofascial trigger point electroacupuncture combined with solifenacin succinate can significantly improve the OABSS and improve the life quality of the patients.


Assuntos
Eletroacupuntura , Bexiga Urinária Hiperativa , Feminino , Humanos , Qualidade de Vida , Succinato de Solifenacina , Resultado do Tratamento , Pontos-Gatilho
10.
J Mater Sci Mater Med ; 29(11): 169, 2018 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-30392085

RESUMO

ZnS:Mn2+ quantum dots (QDs) Fe3O4 QDs/SiO2/P(NIPAAm-co-AAm) core-shell-shell nanocomposites have been successfully fabricated by free radical polymerization method. The average diameter and LCST of ZnS:Mn2+ QDs Fe3O4 QDs/SiO2/P(NIPAAm-co-AAm) (NIPAAm:AAm=90:10) nanocomposites was about 200 nm and 41.1°. It possessed a strong yellow-orange emission peak centered at 589 nm from the Mn2+ 4T1-6A1 transition and the desired superparamagnetic property at room temperature. The DOX encapsulation efficiency and loading capacity was 88% and 15.3 wt%, respectively. The nanocomposites showed the faster drug release behavior at 43 °C than that at 25 °C in vitro release experiment, and exhibited no significant cytotoxicity against the HeLa, HepG2 and HEK293 cell lines. Red fluorescence was observed in the cytoplasm of HeLa cells, confirming its application for biolabeling. Effective tumor inhibition was realized in vivo without the induction of toxicity in mice. ZnS:Mn2+ (QDs) Fe3O4 QDs/SiO2/P(NIPAAm-co-AAm) nanocomposites showed the red fluorescence in the cytoplasm of HeLa cells, faster drug release behavior at 43 °C than that at 25 °C in vitro, and effective tumor inhibition in vivo, confirming its application for drug delivery.


Assuntos
Antineoplásicos/administração & dosagem , Liberação Controlada de Fármacos , Fenômenos Magnéticos , Nanocompostos , Pontos Quânticos , Dióxido de Silício , Animais , Antineoplásicos/química , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Camundongos , Neoplasias Experimentais/tratamento farmacológico , Temperatura
11.
Physiol Mol Biol Plants ; 24(5): 821-831, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30150857

RESUMO

Brassinosteroids (BRs) are a group of plant hormones which play a pivotal role in modulating cell elongation, stress responses, vascular differentiation and senescence. In response to BRs, BRASSINAZOLE-RESISTANT (BZR) transcription factors (TFs) accumulate in the nucleus, where they modulate thousands of target genes and coordinate many biological processes, especially in regulating defense against biotic and abiotic stresses. In this study, 6 BZR TFs of Eucalyptus grandis (EgrBZR) from a genome-wide survey were characterized by sequence analysis and expression profiling against several abiotic stresses. The results showed that BZR gene family in Eucalyptus was slightly smaller compared to Populus and Arabidopsis, but all phylogenetic groups were represented. Various systematic in silico analysis of these TFs validated the basic properties of BZRs, whereas comparative studies showed a high degree of similarity with recognized BZRs of other plant species. In the organ-specific expression analyses, 4 EgrBZRs were expressed in vascular tissue indicating their possible functions in wood formation. Meanwhile, almost all EgrBZR genes showed differential transcript abundance levels in response to exogenously applied BR, MeJA, and SA, and salt and cold stresses. Besides, protein interaction analysis showed that all EgrBZR genes were associated with BR signaling directly or indirectly. These TFs were proposed as transcriptional activators or repressors of abiotic stress response and growth and development pathways of E. grandis by participating in BR signaling processes. These findings would be helpful in resolving the regulatory mechanism of EgrBZRs in stress resistance conditions but require further functional study of these potential TFs in Eucalyptus.

12.
Zhong Nan Da Xue Xue Bao Yi Xue Ban ; 43(12): 1345-1350, 2018 Dec 28.
Artigo em Chinês | MEDLINE | ID: mdl-30643051

RESUMO

OBJECTIVE: To explore the risk factors for and the pathogenic mechanisms of pelvic organ prolapse and urinary incontinence.
 Methods: A total of 2 668 females who completed pelvic floor functional detection from July 2014 to October 2015 in the Physical Examination Center of the Third Xiangya Hospital of Central South University. The patients were divide into 4 groups: an urinary incontinence group, an organ prolapse group, an organ prolapse with urinary incontinence group, and a normal group. We compared the age, BMI, menopause, gravidity and parity, delivery pattern, the coordination of pelvic floor and abdominal muscles among the 4 groups.
 Results: There were statistical differences in age and BMI values among the 4 groups (P<0.05).There were statistical differences in menopause rate, gravidity and parity history among the normal group and the other 3 groups (P<0.05), and between the organ prolapse group and the organ prolapse with urinary incontinence group (P<0.05). However, the urinary incontinence group was not statistically different from the organ prolapse group and the normal group (P>0.05). In the mode of delivery, there were statistical difference among the normal group and the other 3 groups (P<0.05), and between the organ prolapse group with urinary incontinence group and the organ prolapse or the urinary incontinence group (P<0.05). There was no significant difference between the urinary incontinence group and the organ prolapse group (P>0.05). Among the 4 groups, the normal group was the best one in coordination between pelvic floor and abdominal muscles, following by the organ prolapse group, the pelvic organ prolapse group and the urinary incontinence group.
 Conclusion: Aging, menopause, number of pregnancies and delivery, BMI, and mode of delivery all affect the occurrence of pelvic organ prolapse and urinary incontinence. Females with urinary incontinence or organ prolapse are not good in coordination between the pelvic floor and abdominal muscles.


Assuntos
Prolapso de Órgão Pélvico , Incontinência Urinária , Feminino , Humanos , Diafragma da Pelve/patologia , Prolapso de Órgão Pélvico/patologia , Gravidez , Fatores de Risco , Incontinência Urinária/patologia
13.
J Nat Prod ; 80(7): 2110-2117, 2017 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-28719204

RESUMO

Nine new norditerpenoids and dinorditerpenoids, 2-oxonagilactone A (1), 7ß-hydroxynagilactone D (2), nagilactones K and L (3 and 4), 3ß-hydroxynagilactone L (5), 2ß-hydroxynagilactone L (6), 3-epi-15-hydroxynagilactone D (7), 1α-chloro-2ß,3ß,15-trihydroxynagilactone L (8), and 15-hydroxynagilactone L (9), were isolated from the seeds of Podocarpus nagi, along with eight known analogues. The structures of the new compounds were established based on detailed NMR and HRESIMS analysis, as well as from their ECD spectra. The absolute configuration of the known compound 1-deoxy-2α-hydroxynagilactone A (16) was confirmed by single-crystal X-ray diffraction. All of the isolates were tested for their cytotoxic activities against cancer cells. The results indicated that compounds 4 and 6, as well as several known compounds, displayed cytotoxicity against A2780 and HEY cancer cells. Among the new compounds, 2ß-hydroxynagilactone L (6) showed IC50 values of less than 2.5 µM against the two cell lines used. Furthermore, compound 6 induced autophagic flux in A2780 cells, as evidenced by an enhanced expression level of the autophagy marker phosphatidylethanolamine-modified microtubule-associated protein light-chain 3 (LC3-II) and increased mRFP-GFP-LC3 puncta. Also, compound 6 activated the c-Jun N-terminal kinase (JNK) pathway, while pretreatment with the JNK inhibitor SP600125 decreased compound 6-induced autophagy.


Assuntos
Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Medicamentos de Ervas Chinesas/isolamento & purificação , Medicamentos de Ervas Chinesas/farmacologia , Sementes/química , Antracenos/química , Antineoplásicos Fitogênicos/química , Autofagia/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Citotoxinas , Diterpenos/química , Ensaios de Seleção de Medicamentos Antitumorais , Medicamentos de Ervas Chinesas/química , Humanos , Proteínas Quinases JNK Ativadas por Mitógeno/metabolismo , Estrutura Molecular , Ressonância Magnética Nuclear Biomolecular
14.
Molecules ; 21(6)2016 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-27322234

RESUMO

The chemical study on the seeds of Caesalpinia sappan led to the isolation of five new cassane diterpenoids, phanginins R‒T (1-3) and caesalsappanins M and N (4 and 5), together with seven known compounds 6-12. Their structures were elucidated on the basis of NMR and HRESIMS analyses. The absolute configurations of compounds 1 and 4 were determined by the corresponding CD spectra. All the isolated compounds were tested for their cytotoxicity against ovarian cancer A2780 and HEY, gastric cancer AGS, and non-small cell lung cancer A549 cells. Compound 1 displayed significant toxicity against the four cell lines with the IC50 values of 9.9 ± 1.6 µM, 12.2 ± 6.5 µM, 5.3 ± 1.9 µM, and 12.3 ± 3.1 µM, respectively. Compound 1 induced G1 phase cell cycle arrest in A2780 cells. Furthermore, compound 1 dose-dependently induced A2780 cells apoptosis as evidenced by Hoechst 33342 staining, Annexin V positive cells, the up-regulated cleaved-PARP and the enhanced Bax/Bcl-2 ratio. What's more, compound 1 also promoted the expression of the tumor suppressor p53 protein. These findings indicate that cassane diterpenoids might have potential as anti-cancer agents, and further in vivo animal studies and structural modification investigation are needed.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Diterpenos/química , Neoplasias/tratamento farmacológico , Antineoplásicos Fitogênicos/química , Compostos de Bifenilo/química , Compostos de Bifenilo/farmacologia , Caesalpinia/química , Proliferação de Células/efeitos dos fármacos , Diterpenos/isolamento & purificação , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Células HeLa , Humanos , Sementes/química
15.
J Mater Sci Mater Med ; 26(9): 236, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26395361

RESUMO

ZnS:Mn(2+) quantum dots (QDs) were successfully embedded in SiO2 spheres by a reverse microemulsion method. The results showed that the monodispersed core/shell nanocomposites were uniform in size, with the majority of the SiO2 nanoparticles containing one QD in the center of the sphere. The shell thickness of SiO2 increased from 7 to 18 nm as the hydrolysis time of TEOS increased from 20 to 40 h. The quantum yield (QY) of the yellow-orange emission (coming from the Mn(2+) ions (4)T1-(6)A1 transition) for the ZnS:Mn(2+)(3 %) QDs and ZnS:Mn(2+)(3 %) QDs@SiO2 (when t = 40 h) nanocomposites was measured to be 34.5 and 22.4 %, respectively. All samples showed no significant cytotoxicity against the HeLa cells even at a high concentration of 500 µg/ml after incubation for 24 h. The red fluorescence can be observed in the cytoplasm of the HeLa cell, further proving its biolabeling applications.


Assuntos
Materiais Biocompatíveis , Corantes Fluorescentes/química , Manganês/química , Nanoestruturas , Pontos Quânticos , Dióxido de Silício/química , Sulfetos/química , Compostos de Zinco/química , Células HeLa , Humanos , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Difração de Raios X
16.
Planta Med ; 80(13): 1053-66, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25153098

RESUMO

Homoisoflavonoids, a special subclass of flavonoids, are rarely found in nature, mainly existing in Fabaceae and Asparagaceae families and being less common in Polygonaceae, Portulacaceae, Orchidaceae, and Gentianaceae families. Until now, approximately 240 natural occurring homoisoflavonoids have been identified from roots, barks, heartwood, bulbs, leaves, and seeds of the plants from the above mentioned families, which have often been used in traditional medicine. Homoisoflavonoids have been reported with a broad range of bioactivities, including anti-microbial, anti-mutagenic, anti-oxidant, immunomodulatory, anti-diabetic, cytotoxic, anti-angiogenic, vasorelaxant, and anti-inflammatory effects. To organize this review, the homoisoflavonoids were classified into five groups based on their structures: sappanin-type (I), scillascillin-type (II), brazilin-type (III), caesalpin-type (IV), and protosappanin-type (V). The structures of natural occurring homoisoflavonoids are described, and their proposed biosynthetic pathway and recent pharmacological studies are discussed. The main purpose of this review is to provide a comprehensive and up-to-date state of knowledge from phytochemical and pharmacological studies performed on homoisoflavonoids during the past decades. Homoisoflavonoids might have a large potential for further investigations of their bioactivities in order to identify important leads.


Assuntos
Isoflavonas/farmacologia , Extratos Vegetais/farmacologia , Inibidores da Angiogênese/química , Inibidores da Angiogênese/metabolismo , Inibidores da Angiogênese/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/metabolismo , Anti-Infecciosos/farmacologia , Anti-Inflamatórios/química , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Antimutagênicos/química , Antimutagênicos/metabolismo , Antimutagênicos/farmacologia , Antioxidantes/química , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Inibidores Enzimáticos/química , Inibidores Enzimáticos/metabolismo , Inibidores Enzimáticos/farmacologia , Fabaceae/química , Hipoglicemiantes/química , Hipoglicemiantes/metabolismo , Hipoglicemiantes/farmacologia , Fatores Imunológicos/biossíntese , Fatores Imunológicos/química , Fatores Imunológicos/farmacologia , Isoflavonas/biossíntese , Isoflavonas/química , Liliaceae/química , Extratos Vegetais/química , Plantas/química
17.
PeerJ ; 12: e16250, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38188140

RESUMO

Brassinosteroids (BRs) play many pivotal roles in plant growth and development, especially in cell elongation and vascular development. Although its biosynthetic and signal transduction pathway have been well characterized in model plants, their biological roles in Eucalyptus grandis, a major hardwood tree providing fiber and energy worldwide, remain unclear. Here, we treated E. grandis plantlets with 24-epibrassinolide (EBL), the most active BR and/or BR biosynthesis inhibitor brassinazole. We recorded the plant growth and analyzed the cell structure of the root and stem with histochemical methods; then, we performed a secondary growth, BR synthesis, and signaling-related gene expression analysis. The results showed that the BRs dramatically increased the shoot length and diameter, and the exogenous BR increased the xylem area of the stem and root. In this process, EgrBRI1, EgrBZR1, and EgrBZR2 expression were induced by the BR treatment, and the expressions of HD-ZIPIII and cellulose synthase genes were also altered. To further verify the effect of BRs in secondary xylem development in Eucalyptus, we used six-month-old plants as the material and directly applied EBL to the xylem and cambium of the vertical stems. The xylem area, fiber cell length, and cell numbers showed considerable increases. Several key BR-signaling genes, secondary xylem development-related transcription factor genes, and cellulose and lignin biosynthetic genes were also considerably altered. Thus, BR had regulatory roles in secondary xylem development and differentiation via the BR-signaling pathway in this woody plant.


Assuntos
Eucalyptus , Brassinosteroides/farmacologia , Diferenciação Celular , Xilema , Madeira
18.
Front Psychiatry ; 15: 1337847, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38380120

RESUMO

Background: Adolescence is a crucial period for the development of depression, and previous studies have suggested that the Behavioral Activation System (BAS) plays a significant role. However, little is known about the underlying mechanisms. This study aimed to explore the mediating role of anhedonia in the relationship between BAS and depressive symptoms among Chinese adolescents. Method: A total of 1,023 high-school students aged 15-18 years participated in the study, with 916 continuing their participation three months later. All participants completed the Behavioral Inhibition System/Activation System (BIS/BAS) scale, Dimensional Anhedonia Rating Scale (DARS), Children's Depression Inventory (CDI), and the State-Trait Anxiety Inventory (STAI-S/T). Pathway model analysis was performed to examine the concurrent and prospective mediating effects of anhedonia and the potential moderating effect of sex. Result: Anhedonia in the domains of social activities, hobbies and sensory experiences significantly mediated the cross-sectional relationship between BAS and depressive level three months later. Furthermore, the beta-value of the mediating effect of social activities was significantly higher than that of the other domains of hedonic capacity cross-sectionally and longitudinally. However, sex showed no significant moderating effect. Conclusion: Our findings underscore the importance of hedonic capacity, especially within the social domain, in the development of depressive symptoms. These findings contribute to the early diagnosis and prevention of depressive disorders.

19.
Quant Imaging Med Surg ; 14(4): 2927-2937, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38617149

RESUMO

Background: The contrast-enhanced ultrasound Liver Imaging Reporting and Data System (CEUS LI-RADS) is an algorithm for the diagnosis of hepatocellular carcinoma (HCC) in high-risk populations. Previous studies have shown the algorithm to have high specificity and moderate sensitivity. Nevertheless, it is designated for utilization solely with blood pool contrast agents. Sonazoid, a contrast agent that combines blood pools and Kupffer cells properties, has recently gained approval for marketing in an increased number of countries. Enhanced sensitivity in diagnosing HCC may be achieved through the distinctive Kupffer phase (KP) exhibited by Sonazoid. Certain academics have suggested the modified CEUS LI-RADS using Sonazoid. The main criteria of mild and late (≥60 seconds) washout in CEUS LI-RADS LR-5 were replaced by KP (>10 minutes) defects as the primary criteria. The purpose of this research was to evaluate the effectiveness of the modified CEUS LI-RADS using Sonazoid in diagnosing HCC. Methods: Original studies on Sonazoid and CEUS LI-RADS were searched in the PubMed, Embase, Cochrane Library, and Web of Science databases until 13 July 2023, with no restrictions on language. We enrolled studies that applied Sonazoid for CEUS in patients at high risk of HCC and modified CEUS LI-RADS for the diagnosis of intrahepatic nodules. Meta-analyses, evaluations, case studies, correspondences, remarks, and summaries of conferences were excluded. Additionally, studies that fell outside the scope of this study and contained data on the same patients were also excluded. We evaluated the quality of research by employing the Quality Assessment of Diagnostic Accuracy Studies 2 (QUADAS-2) tool. A bivariate mixed effects model was utilized to conduct a meta-analysis, summarizing the sensitivity and specificity in the diagnosis of HCC. The investigation of potential factors contributing to study heterogeneity was conducted using meta-regression analysis. Results: Out of the 103 studies screened, 6 studies (835 lesions) were included in the final results. Modified CEUS LR-5 exhibited a sensitivity of 0.77 [95% confidence interval (CI): 0.70-0.82; I2=71.98%; P=0.00] and a specificity of 0.88 (95% CI: 0.83-0.92; I2=0.00; P=0.47) for HCC diagnosis, with heterogeneity in sensitivity. The presence of heterogeneity in the study was found to have a significant association with factors such as the study design, the number of image reviewers, the proportion of cirrhosis, the proportion of other non-HCC malignancies (OM) cases, and the type of reference standard (P≤0.05). Conclusions: The modified CEUS LI-RADS LR-5 categorization demonstrates a reasonable level of sensitivity 0.77, but an insufficient level of specificity 0.88 when diagnosing HCC. KP defects cannot be used as a primary feature in the diagnosis of HCC by CEUS LI-RADS, perhaps as an ancillary feature.

20.
Stem Cell Reports ; 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38942028

RESUMO

Understanding the regulation of human embryonic stem cells (hESCs) pluripotency is critical to advance the field of developmental biology and regenerative medicine. Despite the recent progress, molecular events regulating hESC pluripotency, especially the transition between naive and primed states, still remain unclear. Here we show that naive hESCs display lower levels of O-linked N-acetylglucosamine (O-GlcNAcylation) than primed hESCs. O-GlcNAcase (OGA), the key enzyme catalyzing the removal of O-GlcNAc from proteins, is highly expressed in naive hESCs and is important for naive pluripotency. Depletion of OGA accelerates naive-to-primed pluripotency transition. OGA is transcriptionally regulated by EP300 and acts as a transcription regulator of genes important for maintaining naive pluripotency. Moreover, we profile protein O-GlcNAcylation of the two pluripotency states by quantitative proteomics. Together, this study identifies OGA as an important factor of naive pluripotency in hESCs and suggests that O-GlcNAcylation has a broad effect on hESCs homeostasis.

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