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1.
Nat Mater ; 22(5): 591-598, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37012436

RESUMO

Large spin-orbit torques (SOTs) generated by topological materials and heavy metals interfaced with ferromagnets are promising for next-generation magnetic memory and logic devices. SOTs generated from y spin originating from spin Hall and Edelstein effects can realize field-free magnetization switching only when the magnetization and spin are collinear. Here we circumvent the above limitation by utilizing unconventional spins generated in a MnPd3 thin film grown on an oxidized silicon substrate. We observe conventional SOT due to y spin, and out-of-plane and in-plane anti-damping-like torques originated from z spin and x spin, respectively, in MnPd3/CoFeB heterostructures. Notably, we have demonstrated complete field-free switching of perpendicular cobalt via out-of-plane anti-damping-like SOT. Density functional theory calculations show that the observed unconventional torques are due to the low symmetry of the (114)-oriented MnPd3 films. Altogether our results provide a path toward realization of a practical spin channel in ultrafast magnetic memory and logic devices.

2.
Anaerobe ; 75: 102585, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35545183

RESUMO

Clostridioides difficile is a Gram-positive, obligate anaerobic, spore-producing intestinal opportunistic pathogen. CDI outbreaks in Europe and the Americas in recent years are a major health concern. Intestinal short-chain fatty acids (SCFAs) are an important energy source for colonic epithelial cells, and the roles of SCFAs in reducing intestinal inflammation, inhibiting intestinal tumors, and regulating gut microbial homeostasis are being actively researched. Furthermore, SCFAs attenuate CDI or directly inhibit C. difficile growth through different pathways in vivo and in vitro. This review assesses the role of SCFAs in CDI and discusses the potential use of these molecules as therapeutic targets for CDI.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Microbioma Gastrointestinal , Infecções por Clostridium/tratamento farmacológico , Células Epiteliais/metabolismo , Ácidos Graxos Voláteis/metabolismo , Humanos
3.
Zhongguo Zhong Yao Za Zhi ; 47(16): 4480-4488, 2022 Aug.
Artigo em Zh | MEDLINE | ID: mdl-36046878

RESUMO

This study established a high performance liquid chromatography(HPLC) method for the simultaneous determination of verbascoside(VB) and its main metabolite caffeic acid(CA) in rat tissue samples. A low-pressure low-oxygen animal experimental chamber was used to simulate the plateau environment for establishing the hypoxic rat model. After intragastric administration of 300 mg·kg~(-1) VB, the normoxic and hypoxic rats were sacrificed for the collection of heart, liver, spleen, lung, kidney, brain, muscle, large intestine, small intestine, and stomach tissue samples at the time points of 30, 60, and 90 min. VB and CA concentrations in each tissue sample were measured by HPLC, and the distribution of VB and CA in normoxic and hypoxic rats was compared. The results showed that after intragastric administration, VB can be rapidly absorbed and distributed into various tissues including brain in both normoxic and hypoxic rats, indicating that VB can pass through the blood-brain barrier. In the gastrointestinal tract, VB was mainly distributed in small intestine, which suggested that the main absorption site of VB was small intestine. A large amount of VB was detected in muscle and lung, and only a small amount in other tissues. CA was detected in other tissues except brain, heart, and muscle. Small intestine had the most abundant CA, followed by stomach, large intestine, and kidney, and only a small amount of CA was detected in the liver, spleen, and lung(<50 ng·mL~(-1)). The results indicated that VB may be mainly absorbed and metabolized in the gastrointestinal tract to produce CA and was possibly excreted through kidney. Compared with normoxic rats, hypoxic rats had reduced and slow distribution of VB and increased ratio of VB concentration in tissue to plasma, which implied that the relative proportion of VB from systemic circulation to tissues was increased in hypoxic rats. This study provides a basis for the application of VB in anti-hypoxia therapy and for the formulation of anti-hypoxia dosing regimens.


Assuntos
Glucosídeos , Fenóis , Animais , Cromatografia Líquida de Alta Pressão , Hipóxia , Polifenóis , Ratos
4.
Anaerobe ; 67: 102295, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33246096

RESUMO

OBJECTIVE: Clostridioides difficile may colonize healthy infants and young children asymptomatically and for the long-term. C. difficile genotypes and the rate and determinants of colonization differ substantially and vary among countries and regions. A 1-year follow-up study was performed to determine the incidence, kinetics and influencing factors of C. difficile intestinal colonization. METHODS: Twenty-nine healthy infants (14 girls and 15 boys) living at home with their parents in Handan City were followed by survey from birth to 1 year of age, specifically from October 2014 through December 2015. C. difficile isolates were typed by PCR ribotyping and analyzed for the presence of toxin genes. RESULTS: During the follow-up study period in the first year of life, 20 of the 29 total enrolled infants acquired C. difficile. A total of 437 fecal samples were obtained, and 111 (25.4%) samples contained C. difficile, including 79 (71.2%) toxigenic strains. The toxigenic isolates comprised six PCR ribotypes, and two PCR ribotypes were identified as nontoxigenic strains. CONCLUSION: Our study showed that C. difficile colonization increase with age during the 12-month period, and the dominant toxigenic types of C. difficile isolates in infants were those involved in long-term colonization. Feeding patterns may affect the dynamic progress of C. difficile colonization.


Assuntos
Portador Sadio/epidemiologia , Clostridioides difficile/classificação , Clostridioides difficile/genética , Infecções por Clostridium/epidemiologia , Biodiversidade , China/epidemiologia , Clostridioides difficile/isolamento & purificação , DNA Bacteriano , Fezes/microbiologia , Comportamento Alimentar , Feminino , Seguimentos , Genótipo , Humanos , Incidência , Lactente , Recém-Nascido , Intestinos/microbiologia , Masculino , Reação em Cadeia da Polimerase , RNA Ribossômico 16S , Ribotipagem
5.
J Neurooncol ; 137(1): 77-82, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29177595

RESUMO

The goal of the study is to examine the practice pattern and survival outcome of adult and pediatric patients with intracranial germinoma. Patients from the National Cancer Database (NCDB) brain tumor registry between the years 2004-2014 with intracranial germinoma were extracted for analysis. Patients who had distant metastasis, received no treatments, or only surgery/chemotherapy alone were excluded. An age cutoff of > 21 years old was used to define the pediatric population. Patients were stratified by the treatments radiation therapy alone (RT) and chemotherapy followed by radiation therapy (C + RT). 445 patients with intracranial germinoma meeting our inclusion criteria were identified. Of the adult patients, 65.7% received RT and 34.3% received C + RT, compared to the pediatric patients, where 31.8% received RT and 68.2% received C + RT. Those patients who received C + RT had a lower radiation dose compared to the RT group (p < 0.001). The 5 and 10 year overall survival (OS) for the entire cohort was 92.6 and 87.9%, respectively. Univariate analysis demonstrated improved OS with younger age, private insurance, C + RT treatment, and pediatric patients. Only age and insurance type remained significant on multivariate analysis. The 5 year OS was 92.6% (RT) versus 97.2% (C + RT) (p = 0.307) and 83.4% (RT) versus 95.4% (C + RT) (p = 0.122) in the pediatric and adult patients, respectively. There is a higher use of C + RT with an accompanied reduction in RT dose in the treatment of intracranial germinoma. There is no difference in survival between the treatment approaches of RT or C + RT in the NCDB patient cohort.


Assuntos
Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/radioterapia , Germinoma/tratamento farmacológico , Germinoma/radioterapia , Adolescente , Adulto , Antineoplásicos , Terapia Combinada , Bases de Dados Factuais , Feminino , Humanos , Estimativa de Kaplan-Meier , Masculino , Avaliação de Processos e Resultados em Cuidados de Saúde , Sistema de Registros , Resultado do Tratamento , Adulto Jovem
6.
J Virol ; 87(10): 5678-96, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23487449

RESUMO

Hepatitis C virus (HCV) causes chronic hepatitis, cirrhosis, and liver cancer. cis-acting RNA elements of the HCV genome are critical for translation initiation and replication of the viral genome. We hypothesized that the coding regions of nonstructural proteins harbor enhancer and essential cis-acting replication elements (CRE). In order to experimentally identify new cis RNA elements, we utilized an unbiased approach to introduce synonymous substitutions. The HCV genome coding for nonstructural proteins (nucleotide positions 3872 to 9097) was divided into 17 contiguous segments. The wobble nucleotide positions of each codon were replaced, resulting in 33% to 41% nucleotide changes. The HCV genome containing one of each of 17 mutant segments (S1 to S17) was tested for genome replication and infectivity. We observed that silent mutations in segment 13 (S13) (nucleotides [nt] 7457 to 7786), S14 (nt 7787 to 8113), S15 (nt 8114 to 8440), S16 (nt 8441 to 8767), and S17 (nt 8768 to 9097) resulted in impaired genome replication, suggesting CRE structures are enriched in the NS5B region. Subsequent high-resolution mutational analysis of NS5B (nt 7787 to 9289) using approximately 51-nucleotide contiguous subsegment mutant viruses having synonymous mutations revealed that subsegments SS8195-8245, SS8654-8704, and SS9011-9061 were required for efficient viral growth, suggesting that these regions act as enhancer elements. Covariant nucleotide substitution analysis of a stem-loop, JFH-SL9098, revealed the formation of an extended stem structure, which we designated JFH-SL9074. We have identified new enhancer RNA elements and an extended stem-loop in the NS5B coding region. Genetic modification of enhancer RNA elements can be utilized for designing attenuated HCV vaccine candidates.


Assuntos
Elementos Facilitadores Genéticos , Regulação Viral da Expressão Gênica , Hepacivirus/genética , Hepacivirus/fisiologia , Humanos , Biologia Molecular/métodos , Mutação de Sentido Incorreto , Proteínas não Estruturais Virais/genética , Virologia/métodos , Replicação Viral
7.
Pak J Med Sci ; 30(2): 361-5, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24772144

RESUMO

UNLABELLED: Objective : To assess how erectile dysfunction (ED) affects the quality of life in male kidney transplant recipients. METHODS: We randomly selected 150 cases of married male kidney transplant recipients. Using the International Index of Erectile Function (IIEF-5) Questionnaire, we divided our research subjects into ED group (n=63) and non-ED group (n = 87). The Short-Form health survey (SF-36) was used to evaluate the quality of life of the recipients. Hamilton Anxiety Rating Scale was used to compare the mental health status of the two groups. RESULTS: No significant differences (P > 0.05) were observed between the ED and non-ED groups in physical functioning (PF), role-physical (RP), or bodily pain (BP). However, the ED group exhibited a lower score (P < 0.05) than the non-ED group in general health (GH), vitality, social functioning (SF), role emotional (RE) and mental health (MH). There were 13 cases in the ED group with anxiety disorders (20.6%), which was clearly more than in the non-ED group (3.4%, P < 0.05). CONCLUSION: Erectile dysfunction is an important factor in the quality of life of male kidney transplant recipients.

8.
J Phys Chem A ; 117(19): 3972-9, 2013 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-23600701

RESUMO

Heterogeneous reactions on mineral aerosols remain an important subject in atmospheric chemistry because of their role in altering the properties of particles and the budget of trace gases. Yet, the role of coadsorption of trace gases onto mineral aerosols and potential synergistic effects are largely uncertain, especially synergistic effects between inorganic and organic gas-phase pollutants. In this study, synergistic effects between HCOOH and SO2 were investigated for the first time using in situ diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS). It was found that the heterogeneous reaction of HCOOH is hindered significantly by coexisting SO2. The total amount of formate decreased, whereas the total amount of sulfate was not affected during coadsorption on the surface of α-Fe2O3. Futhermore, part of the formate on the surface was catalytically decomposed to CO2 by α-Fe2O3 with the help of SO2. These results suggest a possible mechanism for the observed correlations between sulfate and carboxylate in the atmosphere.


Assuntos
Poluentes Atmosféricos/química , Compostos Férricos/química , Formiatos/química , Sulfatos/química , Dióxido de Enxofre/química , Adsorção , Aerossóis , Atmosfera/química , Catálise , Cinética , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Sci Rep ; 13(1): 3454, 2023 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-36859656

RESUMO

Nb and its compounds are widely used in quantum computing due to their high superconducting transition temperatures and high critical fields. Devices that combine superconducting performance and spintronic non-volatility could deliver unique functionality. Here we report the study of magnetic tunnel junctions with Nb as the heavy metal layers. An interfacial perpendicular magnetic anisotropy energy density of 1.85 mJ/m2 was obtained in Nb/CoFeB/MgO heterostructures. The tunneling magnetoresistance was evaluated in junctions with different thickness combinations and different annealing conditions. An optimized magnetoresistance of 120% was obtained at room temperature, with a damping parameter of 0.011 determined by ferromagnetic resonance. In addition, spin-transfer torque switching has also been successfully observed in these junctions with a quasistatic switching current density of 7.3 [Formula: see text] A/cm2.

10.
Int J Infect Dis ; 130: 86-93, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36906122

RESUMO

OBJECTIVES: The aim of this study was to provide an overview of the prevalence and molecular characteristics of Clostridioides difficile infection (CDI) in China in the past 5 years. METHODS: A systematic literature review was conducted according to the preferred reporting items for systematic reviews and meta-analyses guidelines. Nine databases were searched for relevant studies published between January 2017 and February 2022. The Joanna Briggs Institute critical appraisal tool was used to assess the quality of included studies, and R software version 4.1.3 was used for data analysis. Funnel plots and Egger regression tests were also performed to assess publication bias. RESULTS: A total of 50 studies were included in the analysis. The pooled prevalence of CDI in China was 11.4% (2696/26,852). The main circulating C. difficile strains in southern China were ST54, ST3, and ST37, consistent with the overall situation in China. However, the most prevalent genotype in northern China was ST2, which was previously underappreciated. CONCLUSION: Based on our findings, increased awareness and management of CDI is necessary to reduce the prevalence of CDI in China.


Assuntos
Clostridioides difficile , Infecções por Clostridium , Humanos , Clostridioides difficile/genética , Prevalência , Infecções por Clostridium/epidemiologia , China/epidemiologia , Genótipo
11.
Nat Mater ; 11(1): 64-8, 2011 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-22081084

RESUMO

The advent of spin transfer torque effect accommodates site-specific switching of magnetic nanostructures by current alone without magnetic field. However, the critical current density required for usual spin torque switching remains stubbornly high around 10(6)-10(7) A cm(-2). It would be fundamentally transformative if an electric field through a voltage could assist or accomplish the switching of ferromagnets. Here we report electric-field-assisted reversible switching in CoFeB/MgO/CoFeB magnetic tunnel junctions with interfacial perpendicular magnetic anisotropy, where the coercivity, the magnetic configuration and the tunnelling magnetoresistance can be manipulated by voltage pulses associated with much smaller current densities. These results represent a crucial step towards ultralow energy switching in magnetic tunnel junctions, and open a new avenue for exploring other voltage-controlled spintronic devices.

12.
J Phys Chem A ; 116(30): 7959-64, 2012 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-22784368

RESUMO

The heterogeneous kinetic processes of hydrogen peroxide on silicon dioxide (SiO2) and calcium carbonate (CaCO3) have been studied over the temperature range from 253 to 313 K using a Knudsen cell reactor, and the functions of temperature were obtained. The kinetic study indicates that the initial uptake coefficients increase evidently with a temperature decrease. They can be calculated by the equations γBET(SiO2) = [exp(934.5/T - 12.7)]/[1 + exp(934.5/T - 12.7)] and γBET(CaCO3) = [exp(1193.0/T - 11.9)]/[1 + exp(1193.0/T - 11.9)]. On the basis of the temperature dependence of uptake coefficients, the enthalpy (ΔHobs) and entropy (ΔSobs) of uptake progresses were determined to be -(7.77 ± 1.55) KJ mol(-1) and -(105.8 ± 21.2) J K mol(-1) for SiO2 and -(9.92 ± 1.98) KJ mol(-1) and -(98.6 ± 19.7) J K mol(-1) for CaCO3. The activation energies for desorption (Edes) of H2O2 on CaCO3 and SiO2 were calculated to be (5.9 ± 0.9) KJ mol(-1) and (9.15 ± 1.1) KJ mol(-1). The results suggest that hydrogen peroxide could mainly be adsorbed on SiO2 and CaCO3 reversibly in this temperature region, and the quick uptake on these mineral aerosols, especially at low temperature, provides an active surface for further complex reactions.

13.
J Phys Chem A ; 116(1): 437-42, 2012 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-22136045

RESUMO

Multiphase acid-catalyzed oxidation by hydrogen peroxide has been suggested to be a potential route to secondary organic aerosol (SOA) formation from isoprene and its gas-phase oxidation products, but the kinetics and chemical mechanism remain largely uncertain. Here we report the first measurement of uptake of methacrolein into aqueous solutions of sulfuric acid and hydrogen peroxide in the temperature range of 253-293 K. The steady-state uptake coefficients were acquired and increased quickly with increasing sulfuric acid concentration and decreasing temperature. Propyne, acetone, and 2,3-dihydroxymethacrylic acid were suggested as the products. The chemical mechanism is proposed to be the oxidation of carbonyl group and C═C double bonds by peroxide hydrogen in acidic environment, which could explain the large content of polyhydroxyl compounds in atmospheric fine particles. These results indicate that multiphase acid-catalyzed oxidation of methacrolein by hydrogen peroxide can contribute to SOA mass in the atmosphere, especially in the upper troposphere.


Assuntos
Acroleína/análogos & derivados , Poluentes Atmosféricos/química , Peróxido de Hidrogênio/química , Ácidos Sulfúricos/química , Água/química , Acroleína/química , Aerossóis , Butadienos/química , Catálise , Gases , Hemiterpenos/química , Cinética , Oxirredução , Pentanos/química , Soluções , Espectrofotometria Infravermelho , Temperatura
14.
High Alt Med Biol ; 23(2): 173-184, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35708531

RESUMO

Li, Xiao-lin, Wei-gang Wang, Mao-xing Li, Tian-long Liu, Xiu-yu Tian, and Lan Wu. Effects of altitude and duration of differing levels of hypoxic exposure on hypoxia-inducible factor-1α in rat tissues. High Alt Med Biol. 23:173-184, 2022. Objective: This research aimed to evaluate the effects of hypoxia at different altitudes and durations on the expression of hypoxia-inducible factor-1α (HIF-1α) in rat tissues. Methods: A total of 72 Wistar rats were used to investigate the effect of hypoxia at different durations on rat tissues and 72 Wistar rats were used to investigate the effect of hypoxia at different altitudes. Hematoxylin and Eosin (HE) staining was performed to observe the pathological changes of hippocampus tissues, and the expression of HIF-1α of rats under conditions of hypoxia was detected by quantitative real-time polymerase chain reaction and western blotting. Results: According to the pathological results, we found that the degree of the brain, lung, and heart damage and HIF-1α expression, showed an increasing trend as the altitude (1,500, 3,000, 4,500, 6,000, 7,500, and 8,000 m for 12 hours) and duration (0, 6, 12, 24, 36, and 72 hours at 7,500 m) of hypoxia increased. Although there is a significant difference at 8,000 m, considering model stability, animal ethics and cost, we chose 7,500 m as a fixed altitude during hypoxia at different durations. Compared with the normoxic group, the expression of HIF-1α mRNA in the 7,500 m significantly increased by 30.48%, 21.00%, and 12.62%, in brain, lung, and heart tissue (p < 0.01), and HIF-1α mRNA in the 72-hour hypoxic exposure group significantly increased by 52.58%, 20.39%, 27.88% in tissues (p < 0.05). Compared with the normoxic group, HIF-1α protein expressions in the 7,500 m significantly increased by 10.26%, 31.71%, and 13.33% in brain, lung, and heart tissue (p < 0.01, p < 0.01, p < 0.05), and HIF-1α protein expressions in the 72-hour hypoxic exposure group significantly increased by 18.89%, 22.89%, and 29.75% in tissues (p < 0.05). Conclusion: HIF-1α expression in the rat was correlated with altitude and duration of hypoxic exposure.


Assuntos
Altitude , Subunidade alfa do Fator 1 Induzível por Hipóxia , Animais , Hipóxia/metabolismo , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar
15.
J Phys Chem A ; 115(36): 10203-10, 2011 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-21827200

RESUMO

ClC(O)SSCl was prepared by an improved method by the reaction of [(CH(3))(2)CHOC(S)](2)S with SO(2)Cl(2) in hexane. The photoelectron spectra in the gas phase present four distinct regions, corresponding to ionizations from electrons formally located at the S, O, and Cl atoms and at the C═O bond. The vibrational IR and Raman spectra of the liquid were interpreted in terms of the most stable syn-gauche conformer (the O═C double bond syn with respect to the S-S single bond and the C-S single bond gauche with respect to the S-Cl single bond) in equilibrium with the less stable anti-gauche form, both occurring in two enantiomeric forms. The randomization process between the conformers was induced by broad-band UV-visible irradiation in matrix conditions, and several photoproducts were identified by FTIR spectroscopy. The experimental results were complemented by theoretical calculations.

16.
Huan Jing Ke Xue ; 42(10): 5010-5020, 2021 Oct 08.
Artigo em Zh | MEDLINE | ID: mdl-34581145

RESUMO

Focusing on typical mildly saline soil, S1 (EC, 0.62 dS·m-1), and moderately saline soil, S2 (EC, 1.17 dS·m-1), in Hetao Irrigation District of Inner Mongolia, the response of nitrification and denitrification process to salinization degree and the proportion of organic and inorganic nitrogen application were studied. The experimental treatments consisted of(1) no nitrogen(CK), (2) only inorganic nitrogen(U1), and(3) organic nitrogen(U3O1, U1O1, U1O3, and O1) compared to 25%, 50%, 75%, and 100% inorganic nitrogen. The results showed that increasing salinity reduced the soil nitrification potential and increased the soil denitrification capacity. The soil nitrification potential of the S1 soil was 28.81%-69.67% higher than that of the S2 soil, while the denitrification capacity was reduced by 17.16%-88.91%. With an increase in salinity, the AOB abundance and nitrification contribution rate were reduced, but the AOA abundance and nitrification contribution rate were increased. Furthermore, an increase in salinity increased the abundance of nirK and nirS bacteria, and increased N2O/(N2O+N2) production, but reduced the abundance of nosZ. In the S1 soil, the nitrification potential and denitrification capacity of U1O1 were highest, increasing by as much as 18.59% and 15.87%, respectively, compared to the U1 treatment. In the S2 soil, the difference in the soil nitrification potential between the various fertilization treatments was not significant, and the denitrification capacity of the O1 treatment was highest. The S1 and S2 saline soils treated with U1O1 and O1, respectively, had higher AOB gene abundance and nitrification contribution rates, increased nirS and nosZ gene abundances, and significantly reduced N2O/(N2O+N2) product ratios. Our findings suggested that mildly saline soils(120 kg·hm-2 urea+120 kg·hm-2 organic fertilizer) and moderately saline soils(240 kg·hm-2 organic fertilizer) are more conducive to soil nitrification and denitrification processes compared to soils to which inorganic nitrogen is applied alone.


Assuntos
Nitrificação , Solo , Desnitrificação , Nitrogênio , Óxido Nitroso/análise , Microbiologia do Solo
17.
Front Pharmacol ; 12: 745683, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35095483

RESUMO

Crocetin is an aglycone of crocin naturally occurring in saffron and produced in biological systems by hydrolysis of crocin as a bioactive metabolite. It is known to exist in several medicinal plants, the desiccative ripe fruit of the cape jasmine belonging to the Rubiaceae family, and stigmas of the saffron plant of the Iridaceae family. According to modern pharmacological investigations, crocetin possesses cardioprotective, hepatoprotective, neuroprotective, antidepressant, antiviral, anticancer, atherosclerotic, antidiabetic, and memory-enhancing properties. Although poor bioavailability hinders therapeutic applications, derivatization and formulation preparation technologies have broadened the application prospects for crocetin. To promote the research and development of crocetin, we summarized the distribution, preparation and production, total synthesis and derivatization technology, pharmacological activity, pharmacokinetics, drug safety, drug formulations, and preparation of crocetin.

18.
J Tradit Chin Med ; 30(4): 283-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21287786

RESUMO

OBJECTIVE: To probe into the therapeutic effect of perfume stimulating olfaction with volatile oil of Acorus Gramineus on the Alzheimer's disease (AD) rat. METHODS: Totally 50 adult SD rats, male,weighing 300 +/- 10 g, were randomly divided into 5 groups, normal group (group A), olfactory nerve severing model group (group B), AD model group (group C), AD model plus perfume stimulation group (group D), AD model olfactory nerve severing plus perfume stimulation group (group E), 10 rats in each group. After perfume stimulation, Morris maze test was conducted for valuating the learning and memory ability; Malondaldehyde (MDA) content, and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in the brain, and the brain weight were detected. RESULTS: Compared with the AD model group, the average escape latency and swimming distance in 6 days were significantly shorter than those in the group A, B, D (P < 0.01), with no significant differences between the group C and the group E (P > 0.05); Compared with the group A, B and D, MDA content in the group C significantly increased (P < 0.01), and SOD and GSH-Px activities significantly decreased (P < 0.01), and brain weight/body weight decreased significantly in the group C (P < 0.01), with no significant differences between the group C and the group E (P > 0.05). CONCLUSION: Perfume stimultating olfaction with volatile oil of Acorus Gramineus can significantly increase the learning-memory ability, decrease MDA content and increase SOD and GSH-Px activities and weight of brain in AD rats.


Assuntos
Acorus/química , Doença de Alzheimer/terapia , Óleos Voláteis/uso terapêutico , Perfumes/uso terapêutico , Óleos de Plantas/uso terapêutico , Olfato/efeitos dos fármacos , Doença de Alzheimer/fisiopatologia , Doença de Alzheimer/psicologia , Animais , Modelos Animais de Doenças , Humanos , Aprendizagem , Masculino , Memória , Distribuição Aleatória , Ratos , Ratos Sprague-Dawley
19.
Aging (Albany NY) ; 12(21): 21129-21146, 2020 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-33168781

RESUMO

Ovarian cancer refers to all sorts of cancerous growth that starts from the ovary. Dysregulation of long non-coding RNAs (lncRNAs) is associated with ovarian cancer development and progression. Cellular expression and localization of LINC00452 in ovarian cancer cells were detected by qPCR and FISH. The roles of LINC00452 in ovarian carcinogenesis were characterized by MTT, transwell and colony-formation assays in vitro as well as xenograft mouse model. The underlying mechanism was explored by microarray, RIP, Co-IP and luciferase reporter assays. This study identified a novel lncRNA LINC00452 being elevated in both ovarian cancer cells and tumor tissues in patients. Such aberrant expression of LINC00452 was negatively correlated with relapse-free survival of ovarian cancer patients. Overexpression of LINC00452 potentiated CaOV3 cell viability, migration and invasion in vitro as well as xenograft tumor growth in vivo. Evidence from the current study suggests that the carcinogenicity of LINC00452 is partially due to competitive sponging of miR-501-3p followed with release of repression on the ROCK1, a key effector in Rho signaling pathway. Irrespective of its miRNA sponge function, LINC00452 is capable of preventing ROCK1 protein from ubiquitin/proteasome-mediated degradation via their mutual physical interaction. Our study makes LINC00452 a potential therapeutic target for ovarian cancer.


Assuntos
Regulação Neoplásica da Expressão Gênica , MicroRNAs/metabolismo , Neoplasias Ovarianas/metabolismo , RNA Longo não Codificante/metabolismo , Ubiquitinação , Quinases Associadas a rho/metabolismo , Animais , Linhagem Celular Tumoral , Feminino , Humanos , Camundongos Endogâmicos BALB C , Análise de Sobrevida , Ensaios Antitumorais Modelo de Xenoenxerto
20.
Huan Jing Ke Xue ; 41(8): 3811-3821, 2020 Aug 08.
Artigo em Zh | MEDLINE | ID: mdl-33124358

RESUMO

Combining organic fertilizer with chemical fertilizer may affect the microbial processes related to nitrous oxide (N2O) emissions under different degrees of soil salinization. A mild saline soil (S1; electrical conductivity (EC) 0.46 dS·m-1) and moderate saline soil (S2; EC 1.07 dS·m-1) in the Hetao irrigation district of Inner Mongolia were selected. Under equal N rates, the study involved five treatments:U1 (240 kg·hm-2 of chemical fertilizer), U3O1 (180 kg·hm-2 of chemical fertilizer+60 kg·hm-2 of organic fertilizer), U1O1 (120 kg·hm-2 of chemical fertilizer+120 kg·hm-2 of organic fertilizer), U1O3 (60 kg·hm-2 of chemical fertilizer+180 kg·hm-2 of organic fertilizer), and O1 (240 kg·hm-2 of organic fertilizer). In addition, a blank control treatment (CK) was employed to investigate the effects of different fertilization treatments on the N2O emissions from the two saline soils. The results showed that the total N2O emissions from the S2 soil in the same treatment were between 11.86% and 47.23% higher than those from the S1 soil (P<0.05). the dynamic trend of the soil N2O fluxes among the different treatments were similar. The peak N2O emissions occurred after fertilization, and the N2O cumulative emission fluxes accounted for nearly 60% of the emissions during the entire growth period. The proper application of organic fertilizer could significantly reduce the soil N2O emission; the S1 and S2 saline soils treated with U1O1 and O1, respectively, had the lowest N2O emissions, whereby there were significant reductions of 33.62% and 28.51% in comparison to the U1 treatment (P<0.05). Moreover, higher maize yields could be obtained and the N2O flux was significantly positively correlated with the NH4+-N content (P<0.01) but negatively correlated with the NO3--N content. The results demonstrated that nitrification was the main way to produce N2O in the studied salinized maize farmland, and that the addition of organic fertilizer could reduce the N2O production by decreasing the soil NH4+-N content. Based on the changes in the corn yield and a reduction in the greenhouse effect, suitable organic and inorganic fertilizer management models for the Hetao irrigation area were the mild saline soil:120 kg·hm-2 of urea +120 kg·hm-2 of organic fertilizer), and the moderate saline soil:240 kg·hm-2 of organic fertilizer.


Assuntos
Fertilizantes , Solo , Agricultura , China , Fertilizantes/análise , Nitrogênio , Óxido Nitroso/análise
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