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1.
BMC Womens Health ; 24(1): 289, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38750465

RESUMEN

OBJECTIVE: To investigate the extent of knowledge about breastfeeding and attitudes towards infant feeding among spouses of puerperas at the time of discharge from hospital, and explore the factors influencing spousal attitudes toward breastfeeding. METHODS: We conducted a questionnaire survey among 204 spouses of puerperas who were admitted in the maternity wards at a tertiary hospital in Shaanxi Province between October 2021 and December 2021. Respondents who fulfilled the inclusion criteria were identified using convenient sampling. RESULTS: (1) The score of breastfeeding knowledge among spouses prior to discharge from the hospital was (10.56 ± 3.78), with an accuracy rate of 59.6%, and the lowest accuracy rate was for Item 1 "Newborns should be fed on time, not on demand" (42.6%) and Item 5 "Breastfeeding can prevent infant rickets" (49.5%). (2) The average score of spouses' infant feeding attitudes was (58.15 ± 5.55), and the lowest scoring was for Item 17 "Daily urine volume of infants is a reliable indicator to judge whether they get enough breast milk" (1.99 ± 1.14). (3) Generalized linear model analysis showed a more positive attitude (higher score) among spousal attitudes towards infant feeding in those who had received breastfeeding education [OR = 4.588, 95% CI (0.160 ∼ 3.598)] and those with a master's degree or above [OR = 18.278, 95% CI (3.471 ∼ 9.346)]. CONCLUSION: (1) Spouses that received breastfeeding education and those that had a Masters Degree and above had more positive attitude towards infant feeding. (2) Medical staff should focus on puerperas'spouses with degrees below master's level who had not received breastfeeding education. We recommend using a variety of education methods to enable them to acquire more knowledge on breastfeeding and develop a more positive attitude towards breastfeeding, which will further enhance spousal support for breastfeeding, thus positivizing postpartum co-parenting attitudes and improving the rate of exclusive breastfeeding.


Asunto(s)
Lactancia Materna , Conocimientos, Actitudes y Práctica en Salud , Esposos , Humanos , Lactancia Materna/psicología , Lactancia Materna/estadística & datos numéricos , Esposos/psicología , Femenino , Adulto , Masculino , Encuestas y Cuestionarios , Periodo Posparto/psicología , China , Recién Nacido
2.
Bioorg Chem ; 148: 107434, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38744168

RESUMEN

Azaphilones represent a particular group of fascinating pigments from fungal source, with easier industrialization and lower cost than the traditional plant-derived pigments, and they also display a wide range of pharmacological activities. Herein, 28 azaphilone analogs, including 12 new ones, were obtained from the fermentation culture of a marine fungus Penicillium sclerotium UJNMF 0503. Their structures were elucidated by MS, NMR and ECD analyses, together with NMR and ECD calculations and biogenetic considerations. Among them, compounds 1 and 2 feature an unusual natural benzo[d][1,3]dioxepine ring embedded with an orthoformate unit, while 3 and 4 represent the first azaphilone examples incorporating a novel rearranged 5/6 bicyclic core and a tetrahydropyran ring on the side chain, respectively. Our bioassays revealed that half of the isolates exhibited neuroprotective potential against H2O2-induced injury on RSC96 cells, while compound 13 displayed the best rescuing capacity toward the cell viability by blocking cellular apoptosis, which was likely achieved by upregulating the PI3K/Akt signaling pathway.


Asunto(s)
Apoptosis , Benzopiranos , Relación Dosis-Respuesta a Droga , Peróxido de Hidrógeno , Fármacos Neuroprotectores , Penicillium , Fosfatidilinositol 3-Quinasas , Pigmentos Biológicos , Proteínas Proto-Oncogénicas c-akt , Apoptosis/efectos de los fármacos , Penicillium/química , Fármacos Neuroprotectores/farmacología , Fármacos Neuroprotectores/química , Fármacos Neuroprotectores/aislamiento & purificación , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/antagonistas & inhibidores , Fosfatidilinositol 3-Quinasas/metabolismo , Pigmentos Biológicos/farmacología , Pigmentos Biológicos/química , Pigmentos Biológicos/aislamiento & purificación , Peróxido de Hidrógeno/farmacología , Peróxido de Hidrógeno/antagonistas & inhibidores , Estructura Molecular , Benzopiranos/farmacología , Benzopiranos/química , Benzopiranos/aislamiento & purificación , Relación Estructura-Actividad , Animales , Supervivencia Celular/efectos de los fármacos , Ratas , Transducción de Señal/efectos de los fármacos
3.
Paediatr Perinat Epidemiol ; 38(2): 130-141, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38168744

RESUMEN

BACKGROUND: Little is known about the long-term trends of preterm birth rates in China and their geographic variation by province. OBJECTIVES: To estimate the annual spatial-temporal distribution of preterm birth rates in China by province from 1990 to 2020. DATA SOURCES: We searched PubMed, EMBASE, Web of Science, CNKI, WANFANG and VIP from January 1990 to September 2023. STUDY SELECTION AND DATA EXTRACTION: Studies that provided data on preterm births in China after 1990 were included. Data were extracted following the Guidelines for Accurate and Transparent Health Estimates Reporting. SYNTHESIS: We assessed the quality of each survey using a 9-point checklist. We estimated the annual preterm birth risk by province using Bayesian multilevel logistic regression models considering potential socioeconomic, environmental, and sanitary predictors. RESULTS: Based on 634 survey data from 343 included studies, we found a gradual increase in the preterm birth risk in most provinces in China since 1990, with an average annual increase of 0.7% nationally. However, the preterm birth rates in Inner Mongolia, Hubei, and Fujian Province showed a decline, while those in Sichuan were quite stable since 1990. In 2020, the estimates of preterm birth rates ranged from 2.9% (95% Bayesian credible interval [BCI] 2.1, 3.8) in Inner Mongolia to 8.5% (95% BCI 6.6, 10.9) in Jiangxi, with the national estimate of 5.9% (95% BCI 4.3, 8.1). Specifically, some provinces were identified as high-risk provinces for either consistently high preterm birth rates (e.g. Jiangxi) or relatively large increases (e.g. Shanxi) since 1990. CONCLUSIONS: This study provides annual information on the preterm birth risk in China since 1990 and identifies high-risk provinces to assist in targeted control and intervention for this health issue.


Asunto(s)
Nacimiento Prematuro , Femenino , Recién Nacido , Humanos , Nacimiento Prematuro/epidemiología , Teorema de Bayes , China/epidemiología , Tasa de Natalidad
4.
J Agric Food Chem ; 71(44): 16715-16726, 2023 Nov 08.
Artículo en Inglés | MEDLINE | ID: mdl-37889105

RESUMEN

Zearalenone (ZEN) is well known as a kind of endocrine disruptor whose exposure is capable of causing reproductive toxicity in animals. Cyanidin-3-O-glucoside (C3G) is a derivative of cyanidin and owns multiple biofunctions, and prior efforts have suggested that C3G has therapeutic actions for reproductive diseases. In this article, a ZEN exposure model during primordial follicle assembly was constructed using the in vitro culture platform of neonatal mouse ovaries. We investigated the protective effect of C3G on ZEN-induced ovarian toxicity during primordial follicle assembly in mice, as well as its potential mechanism. Interestingly, we observed that C3G could effectively protect the ovary from ZEN damage, mainly by restoring primordial follicle assembly, which upregulated the expression of LHX8 and SOHLH1 proteins and relieved ZEN-induced DNA damage. Next, to explore the mechanism by which C3G rescued ZEN-induced injury, we performed RNA sequencing (RNA-seq). The bioinformatic analysis illustrated that the rescue pathway of C3G was associated with p53-Gadd45a signaling and cell cycle. Then, western blotting and flow cytometry results revealed that C3G restored the expression levels of cyclin-dependent kinase 6 (CDK6) and cyclin D2 (CCND2) and regulated the ovarian cell cycle to normal. In conclusion, our findings manifested that C3G could alleviate ZEN-induced primordial follicle assembly impairment by restoring the cell cycle involved in p53-GADD45a signaling.


Asunto(s)
Ovario , Zearalenona , Femenino , Animales , Ratones , Zearalenona/toxicidad , Proteína p53 Supresora de Tumor , Antocianinas/farmacología , Glucósidos/farmacología
5.
Cell Death Dis ; 14(2): 134, 2023 02 17.
Artículo en Inglés | MEDLINE | ID: mdl-36797258

RESUMEN

In order to reveal the complex mechanism governing the mitotic/meiotic switch in female germ cells at epigenomic and genomic levels, we examined the chromatin accessibility (scATAC-seq) and the transcriptional dynamics (scRNA-seq) in germ cells of mouse embryonic ovary between E11.5 to 13.5 at single-cell resolution. Adopting a strict transcription factors (TFs) screening framework that makes it easier to understand the single-cell chromatin signature and a TF interaction algorithm that integrates the transcript levels, chromatin accessibility, and motif scores, we identified 14 TFs potentially regulating the mitotic/meiotic switch, including TCFL5, E2F1, E2F2, E2F6, E2F8, BATF3, SP1, FOS, FOXN3, VEZF1, GBX2, CEBPG, JUND, and TFDP1. Focusing on TCFL5, we constructed Tcfl5+/- mice which showed significantly reduced fertility and found that decreasing TCFL5 expression in cultured E12.5 ovaries by RNAi impaired meiotic progression from leptotene to zygotene. Bioinformatics analysis of published results of the embryonic germ cell transcriptome and the finding that in these cells central meiotic genes (Stra8, Tcfl5, Sycp3, and E2f2) possess open chromatin status already at the mitotic stage together with other features of TCFL5 (potential capability to interact with core TFs and activate meiotic genes, its progressive activation after preleptotene, binding sites in the promoter region of E2f2 and Sycp3), indicated extensive amplification of transcriptional programs associated to mitotic/meiotic switch with an important contribution of TCFL5. We conclude that the identified TFs, are involved in various stages of the mitotic/meiotic switch in female germ cells, TCFL5 primarily in meiotic progression. Further investigation on these factors might give a significant contribution to unravel the molecular mechanisms of this fundamental process of oogenesis and provide clues about pathologies in women such as primary ovarian insufficiency (POI) due at least in part to meiotic defects.


Asunto(s)
Factores de Transcripción , Transcriptoma , Femenino , Animales , Ratones , Factores de Transcripción/genética , Factores de Transcripción/metabolismo , Transcriptoma/genética , Epigenómica , Meiosis/genética , Cromatina/genética
6.
Fitoterapia ; 150: 104856, 2021 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-33582267

RESUMEN

Seven new compounds including five aromatic butenolide analogues (1-5), one quinazolinone alkaloid (6) and one benzoic acid derivative (7), along with eleven known co-metabolites (8-18), were isolated from Aspergillus terreus SCAU011, a fungus from the rhizosphere sediment of a mangrove plant Rhizophora stylosa. The structures of these isolates were established by a combination of MS, NMR and ECD data analyses, as well as chemical method. Compound 3 is a rare ring-open aromatic butenolide, while 6 represents the first natural ring-open benzomalvin-type quinazolinone alkaloid. Also, the previously reported structures for asperlides A-C were proposed to be revised in the present work. The COX-2 inhibitory, α-glucosidase inhibitory, antioxidant and antibacterial activities of all the compounds were assessed. While compounds 4, 6, 11 and 18 exhibited better COX-2 inhibitory activity than the positive control celecoxib, compounds 9 and 10 showed significant α-glucosidase inhibitory activity with IC50 values of 56.1 and 12.9 µM, respectively. Meanwhile, half of the tested samples (1, 8-11 and 15-17) exerted similar or better antioxidant activity compared with the reference drug curcumin, and compounds 3, 9, 17 and 18 displayed moderate antibacterial effect against Staphylococcus aureus.


Asunto(s)
4-Butirolactona/análogos & derivados , Aspergillus/química , Sedimentos Geológicos/microbiología , Rhizophoraceae/microbiología , 4-Butirolactona/aislamiento & purificación , 4-Butirolactona/farmacología , Antibacterianos/aislamiento & purificación , Antibacterianos/farmacología , Antioxidantes/aislamiento & purificación , Antioxidantes/farmacología , China , Inhibidores de la Ciclooxigenasa 2/aislamiento & purificación , Inhibidores de la Ciclooxigenasa 2/farmacología , Inhibidores de Glicósido Hidrolasas/aislamiento & purificación , Inhibidores de Glicósido Hidrolasas/farmacología , Estructura Molecular , Staphylococcus aureus/efectos de los fármacos
7.
Medicine (Baltimore) ; 99(50): e23414, 2020 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-33327266

RESUMEN

Our study aimed to investigate the effect of intravenous thrombolysis with alteplase and edaravone on cerebral hemodynamics and T lymphocyte level in patients harboring acute cerebral infarction.There involved a total of 118 patients with acute cerebral infarction from November 2017 to May 2019 in our hospital were randomly divided into 2 groups: the observation group (59 patients were treated with intravenous thrombolysis with alteplase combined with edaravone) and the control group (59 patients were treated with intravenous thrombolysis of alteplase). The clinical effect, neurological function, cerebral hemodynamic index, T lymphocyte level, oxygen free radical scavenging level and oxidative stress index of the 2 groups were observed and compared.Before the treatment, there were no significant differences in neurological function, cerebral hemodynamic indexes, T-lymphocyte level, oxygen free radical scavenging level and oxidative stress indexes between the 2 groups (P > .05). After the treatment, the neurological function, cerebral hemodynamic indexes, T-lymphocyte level, oxygen free radical scavenging level and oxidative stress indexes of the 2 groups were significantly improved. In addition, the observation group exerted greater beneficial effect in terms of the clinical effect, neurologic function, cerebral hemodynamic index, T lymphocyte level, oxygen free radical scavenging level and oxidative stress index than those of the control group (P < .05).The intravenous thrombolysis with alteplase and edaravone is effective in the treatment of acute cerebral infarction, which also provides better results in terms of improving the clinical efficacy and prognosis of patients and might be an alternative option for clinical practice.


Asunto(s)
Infarto Cerebral/tratamiento farmacológico , Edaravona/administración & dosificación , Fibrinolíticos/administración & dosificación , Terapia Trombolítica/métodos , Activador de Tejido Plasminógeno/administración & dosificación , Enfermedad Aguda , Administración Intravenosa , Adulto , Anciano , Circulación Cerebrovascular/efectos de los fármacos , Quimioterapia Combinada , Femenino , Hemodinámica/efectos de los fármacos , Humanos , Masculino , Persona de Mediana Edad , Linfocitos T/efectos de los fármacos , Resultado del Tratamiento
8.
World J Hepatol ; 12(10): 766-774, 2020 Oct 27.
Artículo en Inglés | MEDLINE | ID: mdl-33200015

RESUMEN

Angiogenesis plays an important role in the occurrence and development of tumors. Registered tyrosine kinase inhibitors targeting vascular endothelial growth factor reduce angiogenesis. Apatinib, a tyrosine kinase inhibitor, can specifically inhibit vascular endothelial growth factor receptor 2, showing encouraging anti-tumor effects in a variety of tumors including advanced hepatocellular carcinoma (HCC). This article intends to review the clinical research and application prospects of apatinib in the field of HCC.

9.
Brain Behav ; 10(8): e01661, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-32533644

RESUMEN

PURPOSE: The present clinical study was conducted to investigate the effect of oxiracetam combined with ginkgo biloba extract in treating patients with acute intracerebral hemorrhage. METHODS: Ninety-eight patients with acute cerebral hemorrhage admitted to our hospital were divided into three groups. The differences of brain edema and cerebral hemorrhage were compared between the three groups after 1 and 2 weeks of treatment, and the recovery of neurological function, serum inflammatory factors, AQP-4, MMP-9, cognitive function, activities of daily living, and adverse reactions were compared between the three groups after 2 weeks of treatment. RESULTS: There was no significant difference among the three groups before treatment (p > .05). After treatment, the recovery of neurological function, serum inflammatory factors, AQP-4, MMP-9 levels, cognitive function, and activities of daily living were improved. Among them, the neurological function recovery, serum inflammatory factors, AQP-4, MMP-9 levels, cognitive function, and activities of daily living in the combined treatment group and the control group elicited greater results than those in the routine group. The results of the combined treatment group showed the most significant difference (p < .05). The concentration of IL-6 decreased from 135.98 ± 12.54 to 91.83 ± 7.69 pg/ml, AQP-4 from 227.55 µg/L ± 21.06 to 114.31 ± 9.22 µg/L, and MMP-9 from 172.39 ± 9.81 to 94.98 ± 5.01 ng/ml. In addition, the neurological function recovery, the levels of serum inflammatory factors, cognitive function, and activities of daily living in the combined treatment group were better than those in the control group (p < .05). The mean score of MRS in the combined treatment group decreased from 3.36 ± 0.98 at admission to 1.91 ± 0.38. CONCLUSION: Oxiracetam combined with Ginkgo biloba extract in the treatment of acute cerebral hemorrhage has a significant improvement effect.


Asunto(s)
Hemorragia Cerebral , Ginkgo biloba , Actividades Cotidianas , Adulto , Hemorragia Cerebral/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Fitoterapia , Extractos Vegetales , Pirrolidinas
10.
Cancer Lett ; 476: 67-74, 2020 04 28.
Artículo en Inglés | MEDLINE | ID: mdl-32061752

RESUMEN

Drug resistance is a big problem in cancer treatment and one of the most prominent mechanisms underlain is overexpression of ATP-binding cassette (ABC) transporters, particularly ABCB1, ABCC1 and ABCG2. Inhibition of ABC transporters is an important approach to overcome drug resistance. The inositol-requiring enzyme 1α (IRE1α), an arm of unfolded protein response (UPR), splices XBP1 mRNA to generate an active transcription factor XBP1s. UPR is implicated in drug resistance. However, the underlying mechanism is unclear. We found that the anticancer drugs such as 5-fluorouracil (5-FU) activated the IRE1α-XBP1 pathway to induce the expression of ABCB1, ABCC1 and ABCG2 in colon cancer cells. Inhibition of IRE1α RNase activity with small molecule 4µ8c suppressed the drug-induced expression of these ABC transporters and sensitized 5-FU-resistant colon cancer cells to drug treatment. In vivo xenograft assay indicates that administration of 4µ8C substantially enhanced the efficacy of 5-FU chemotherapy on 5-FU-resistant colon cancer cells. These results suggest that IRE1α-targeting might be a strategy to cope with drug resistance of colon cancer.


Asunto(s)
Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/antagonistas & inhibidores , Neoplasias del Colon/tratamiento farmacológico , Resistencia a Antineoplásicos , Endorribonucleasas/antagonistas & inhibidores , Fluorouracilo/farmacología , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/antagonistas & inhibidores , Proteínas de Neoplasias/antagonistas & inhibidores , Proteínas Serina-Treonina Quinasas/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP/antagonistas & inhibidores , Subfamilia B de Transportador de Casetes de Unión a ATP/genética , Subfamilia B de Transportador de Casetes de Unión a ATP/metabolismo , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/genética , Transportador de Casetes de Unión a ATP, Subfamilia G, Miembro 2/metabolismo , Animales , Antimetabolitos Antineoplásicos/farmacología , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Neoplasias del Colon/metabolismo , Neoplasias del Colon/patología , Resistencia a Múltiples Medicamentos , Endorribonucleasas/genética , Endorribonucleasas/metabolismo , Femenino , Regulación Neoplásica de la Expresión Génica , Humanos , Ratones , Ratones Endogámicos BALB C , Ratones Desnudos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/metabolismo , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Proteínas Serina-Treonina Quinasas/genética , Proteínas Serina-Treonina Quinasas/metabolismo , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
11.
Thromb Haemost ; 119(5): 758-765, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30808044

RESUMEN

The binding of programmed death 1 (PD-1) to its ligands PD-L1 and PD-L2 on antigen-presenting cells turns off autoreactive T cells and induces peripheral tolerance. Aberrant PD-1/PD-L signalling could result in a breakdown of peripheral tolerance and lead to autoimmune diseases. In this study, we detected PD-1 and PD-L expression on T cells and dendritic cells (DCs) in immune thrombocytopenia (ITP) patients with active disease by flow cytometry. The effects of PD-L1-Fc fusion protein (PD-L1-Fc) on T cells and on secretion of interferon-γ (IFN-γ) and interleukin-2 (IL-2) were detected by flow cytometry and enzyme-linked immunosorbent assay, respectively. Compared with healthy controls, PD-1 expression was significantly increased in CD4+ T cells and CD8+ T cells from patients with active ITP. However, PD-L1 expression on monocyte-derived DCs was lower in patients with active ITP than in healthy controls. In vitro assays revealed that PD-L1-Fc increased T cell apoptosis, inhibited activation and proliferation of CD4+ T cells and CD8+ T cells and decreased IFN-γ and IL-2 secretion in patients with active ITP. These results suggest that the aberrant PD-1/PD-L negative co-stimulatory pathway may play a role in ITP. Enhancing PD-1/PD-L signalling might be a promising therapeutic approach for ITP patients by enhancing T cell apoptosis, inhibiting T cell activation and proliferation and reducing secretion of inflammatory factors.


Asunto(s)
Antígeno B7-H1/metabolismo , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD8-positivos/inmunología , Receptor de Muerte Celular Programada 1/metabolismo , Púrpura Trombocitopénica Idiopática/metabolismo , Adolescente , Adulto , Anciano , Apoptosis , Antígeno B7-H1/genética , Proliferación Celular , Células Cultivadas , Femenino , Humanos , Activación de Linfocitos/efectos de los fármacos , Masculino , Persona de Mediana Edad , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/farmacología , Transducción de Señal , Regulación hacia Arriba , Adulto Joven
12.
Neuropsychiatr Dis Treat ; 14: 1035-1046, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29713173

RESUMEN

INTRODUCTION: Previously published articles have suggested that BDNF rs6265 G>A polymorphism is a potential risk factor for epilepsy. However, the results were not consistent. METHODS: We conducted a meta-analysis to explore the association between BDNF rs6265 G>A polymorphism and epilepsy risk. Four online databases were searched, and related studies were reviewed from their inception up to June 20, 2017. ORs and corresponding 95% CIs were used to calculate the associations of each genetic model. Overall, 10 case-control publications involving 9,512 subjects were included in this meta-analysis. RESULTS: Significant associations were found between BDNF rs6265 G>A polymorphism and epilepsy (A vs G: OR=0.88, 95% CI=0.83-0.94, P<0.01, I2=0%; GA vs GG: OR=0.88, 95% CI=0.79-0.97, P=0.01, I2=0%; AA vs GG: OR=0.79, 95% CI=0.70-0.90, P<0.01, I2=0%; GA+AA vs GG: OR=0.85, 95% CI=0.77-0.94, P<0.01, I2=0%; AA vs GG+GA: OR=0.85, 95% CI=0.76-0.95, P=0.01, I2=0%). Subgroup analysis also showed similar results in an Asian population. CONCLUSION: Our meta-analysis indicated that BDNF rs6265 G>A polymorphism might be involved in epilepsy susceptibility, especially in the Asian population.

13.
Dalton Trans ; 46(46): 16321-16326, 2017 Nov 28.
Artículo en Inglés | MEDLINE | ID: mdl-29143044

RESUMEN

The development of an earth-abundant, first-row water oxidation catalyst that operates at a high TOF and a low overpotential remains a fundamental chemical challenge. Cobalt complexes are important members of water oxidation catalysts. Herein, we report a cobalt-based robust homogeneous water oxidation catalyst, which can electrocatalyze water oxidation at a high pH and a low overpotential (η = 520 mV) in phosphate buffer. This homogeneous system exhibits a high turnover frequency (about 5 s-1) of catalyzing water oxidation to produce oxygen at η = 720 mV. We speculate the mechanism of the reaction that O-O bond formation prefers a HO-OH coupling in catalytic water oxidation.

14.
Acta Pharmacol Sin ; 38(10): 1401-1411, 2017 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-28649131

RESUMEN

Pseudolaric acid B (PAB), a diterpene acid isolated from the root bark of Pseudolarix kaempferi Gordon, exerts anti-tumor effects in several cancer cell lines. Our previous study showed that PAB mainly induced senescence via p53-p21 activation rather than apoptosis in suppression of the growth of human lung cancer A549 cells (p53 wild-type). In p53-null human lung cancer H1299 cells, however, PAB caused apoptosis without senescence. In this study we investigated what mechanism was responsible for the switch from senescence to apoptosis in PAB-treated human lung cancer cell lines. Senescent cells were examined by SA-ß-gal staining. Glucose uptake and the apoptosis ratio were assessed using a FACScan flow cytometer. Commercial assay kits were used to measure the levels of ATP and lactate. Transfection of siRNA was used to knockdown the expression of p53 or p21. Western blot analysis was applied to measure the protein expression levels. In p53 wild-type A549 cells, PAB (20 µmol/L) caused senescence, and time-dependently increased glucose utilization; knockdown of p53 or p21 significantly decreased the uptake and metabolism of glucose but elevated PAB-induced apoptosis. Inhibition of glucose utilization using a glycolytic inhibitor 2-DG (1 mmol/L) significantly enhanced apoptosis induction. Similar results were observed in another p53 wild-type H460 cells treated with PAB. Opposite results were found in p53-null H1299 cells, where PAB time-dependently decreased glucose utilization, and induced only apoptosis. Our results demonstrate that PAB-induced senescence is associated with enhanced glucose utilization, and lower glucose utilization might contribute to apoptosis induction. Thus, blocking glucose utilization contributes to the switch from senescence to apoptosis, and p53 plays an important role in this process.


Asunto(s)
Apoptosis/efectos de los fármacos , Diterpenos/farmacología , Glucosa/metabolismo , Neoplasias Pulmonares/tratamiento farmacológico , Células A549 , Antineoplásicos Fitogénicos/farmacología , Western Blotting , Línea Celular Tumoral , Senescencia Celular/efectos de los fármacos , Inhibidor p21 de las Quinasas Dependientes de la Ciclina/genética , Citometría de Flujo , Técnicas de Silenciamiento del Gen , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/patología , Factores de Tiempo , Proteína p53 Supresora de Tumor/genética
15.
J Biol Chem ; 290(24): 15327-36, 2015 Jun 12.
Artículo en Inglés | MEDLINE | ID: mdl-25925952

RESUMEN

Intestinal epithelial cells (IECs) have critical roles in maintaining homeostasis of intestinal epithelium. Endoplasmic reticulum (ER) stress is implicated in intestinal epithelium homeostasis and inflammatory bowel disease; however, it remains elusive whether IRE1α, a major sensor of ER stress, is directly involved in these processes. We demonstrate here that genetic ablation of Ire1α in IECs leads to spontaneous colitis in mice. Deletion of IRE1α in IECs results in loss of goblet cells and failure of intestinal epithelial barrier function. IRE1α deficiency induces cell apoptosis through induction of CHOP, the pro-apoptotic protein, and sensitizes cells to lipopolysaccharide, an endotoxin from bacteria. IRE1α deficiency confers upon mice higher susceptibility to chemical-induced colitis. These results suggest that IRE1α functions to maintain the intestinal epithelial homeostasis and plays an important role in defending against inflammation bowel diseases.


Asunto(s)
Colitis/prevención & control , Retículo Endoplásmico/metabolismo , Endorribonucleasas/fisiología , Mucosa Intestinal/metabolismo , Proteínas Serina-Treonina Quinasas/fisiología , Animales , Secuencia de Bases , Línea Celular , Cartilla de ADN , Endorribonucleasas/genética , Homeostasis , Ratones , Ratones Transgénicos , Reacción en Cadena de la Polimerasa , Proteínas Serina-Treonina Quinasas/genética , ARN Interferente Pequeño/genética
16.
Arch Oral Biol ; 58(9): 1238-45, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23668807

RESUMEN

OBJECTIVES: Damage to salivary gland after radiotherapy for head and neck malignant tumours can lead to irreversible oral complaints, which severely impair quality of life. The protective effect of α1-adrenoceptor activation on the salivary glands after irradiation has previously been demonstrated. However, the exact mechanism remains unclear. In this study, we investigated the underlying cytoprotective mechanism of α1-adrenoceptor activation in rat submandibular glands after irradiation. STUDY DESIGN: Rats were locally irradiated using a linear accelerator in the head and neck region with a dose of 20Gy. After irradiation, phenylephrine (5mg/kg) was injected intraperitoneally for 7 successive days and the submandibular glands were then collected. The antiapoptotic effect of phenylephrine on the gland was examined by TUNEL, the proliferative cellular nuclei antigen (PCNA) was determined by immunohistochemistry, and the activation of c-Jun N-terminal kinase (JNK) was detected by Western blot. RESULTS: The irradiation only group showed severe atrophy, increased apoptosis, enhanced cell proliferation, and the phosphorylation of JNK was markedly increased by 26.89% (P<0.05), compared to the control. The phenylephrine-treated group, however, showed remarkably alleviated atrophy, decreased apoptosis, and further increased cell proliferation, and the phosphorylation of JNK was markedly decreased by 36.00% (P<0.05), compared to the irradiation only group. CONCLUSIONS: The data showed that the underlying protective mechanism of α1-adrenoceptor activation in irradiated gland might be related to improved cell proliferation, inhibited cell apoptosis, and depressed activation of JNK. It could be helpful in protecting salivary glands against irradiation damage.


Asunto(s)
Agonistas de Receptores Adrenérgicos alfa 1/farmacología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Proteínas Quinasas JNK Activadas por Mitógenos/metabolismo , Fenilefrina/farmacología , Fosforilación/efectos de los fármacos , Glándula Submandibular/efectos de la radiación , Animales , Antígenos Nucleares , Apoptosis/efectos de la radiación , Proliferación Celular/efectos de la radiación , Inmunohistoquímica , Etiquetado Corte-Fin in Situ , Masculino , Fosforilación/efectos de la radiación , Ratas , Ratas Wistar , Glándula Submandibular/metabolismo
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