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1.
Microb Pathog ; 180: 106146, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37150309

RESUMO

Talaromycosis, namely Talaromyces marneffei infection, is increasing gradually and has a high mortality rate even under antifungal therapy. Although autophagy acts differently on different pathogens, it is a promising therapeutic strategy. However, information on autophagy in macrophages and animals upon infection by T. marneffei is still limited. Therefore, several models were employed here to investigate the role of autophagy in host defense against T. marneffei, including RAW264.7 macrophages as in vitro models, different types of Caenorhabditis elegans and BALB/c mice as in vivo models. We applied the clinical T. marneffei isolate SUMS0152 in this study. T. marneffei-infected macrophages exhibit increased formation of autophagosomes. Further, macrophage autophagy promoted by rapamycin or Earle's balanced salt solution (EBSS) inhibited the viability of intracellular T. marneffei. In vivo, compared with uninfected Caenorhabditis elegans, the wild-type nematodes upregulated the expression of the autophagy-related gene lgg-1 and atg-18, and nematodes carrying GFP reporter were induced to form autophagosomes (GFP::LGG-1) after T. marneffei infection. Furthermore, the knockdown of lgg-1 significantly reduced the survival rate of T. marneffei-infected nematodes. Likewise, the autophagy activator rapamycin reduced the fungal burden and suppressed lung inflammation in a mouse model of infection. In conclusion, autophagy is essential for host defense against T. marneffei in vitro and in vivo. Therefore, autophagy may be an attractive target for developing new therapeutics to treat talaromycosis.


Assuntos
Caenorhabditis elegans , Talaromyces , Animais , Camundongos , Autofagia , Sirolimo/farmacologia
2.
Zhongguo Zhong Yao Za Zhi ; 44(5): 1019-1025, 2019 Mar.
Artigo em Zh | MEDLINE | ID: mdl-30989864

RESUMO

A stable hepatoma cell line(Hep G2 cell) insulin resistance model was established and used to analyze the effect of effective components of Mori Folium in alleviating insulin resistance,and preliminary explore the mechanism for alleviating insulin resistance. The Hep G2 insulin action concentration and the duration of action were investigated using the glucose oxidase method(GOD-POD method) to establish a stable Hep G2 insulin resistance model. Normal control group,model group,Mori Folium polysaccharide group,Mori Folium flavonoid group and rosiglitazone group were divided to determine the glucose consumption. The effect of Mori Folium effective components on Hep G2 insulin resistance was analyzed. The mRNA expressions of JNK,IRS-1 and PDX-1 in each group were detected by Real-time quantitative PCR(qRT-PCR). The protein expressions of p-JNK,IRS-1 and PDX-1 were detected by Western blot. And the mechanism of effective components of Mori Folium in alleviating insulin resistance was investigated. The results showed that the glucose consumption was significantly decreased in the insulin resistance cells after incubation with 25. 0 mg·L-1 insulin for 36 h(P<0. 01),and the model was relatively stable within 36 h. Mori Folium polysaccharides and flavonoids all alleviated insulin resistance,among which Mori Folium flavonoids had better effect in alleviating Hep G2 insulin resistance(P<0. 05). The qRT-PCR analysis showed that Mori Folium polysaccharides and flavonoids could inhibit JNK and IRS-1 mRNA expressions,while enhancing PDX-1 mRNA expression. Western blot analysis displayed that Mori Folium polysaccharides and flavonoids could inhibit p-JNK and IRS-1 protein expressions,while enhancing PDX-1 protein expression. Mori Folium polysaccharides and flavonoids can alleviate insulin resistance in Hep G2 cells,and its mechanism may be the alleviation of insulin resistance by inhibiting JNK signaling pathway.


Assuntos
Medicamentos de Ervas Chinesas/farmacologia , Resistência à Insulina , Sistema de Sinalização das MAP Quinases , Morus/química , Glucose , Células Hep G2 , Proteínas de Homeodomínio/metabolismo , Humanos , Insulina , Proteínas Substratos do Receptor de Insulina/metabolismo , MAP Quinase Quinase 4/metabolismo , Folhas de Planta/química , Transativadores/metabolismo
3.
Opt Express ; 25(12): 13807-13815, 2017 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-28788922

RESUMO

We demonstrate a quantum cascade laser with active regions consisting of InAs quantum dots deposited on GaAs buffer layers that are embedded in InGaAs wells confined by InAlAs barriers. Continuous wave room temperature lasing at the wavelength of 7.2 µm has been demonstrated with the threshold current density as low as 1.89 kA/cm2, while in pulsed operational mode lasing at temperatures as high as 110 °C had been observed. A phenomenological theory explaining the improved performance due to weak localization of states had been formulated.

4.
Opt Express ; 24(17): 19545-51, 2016 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-27557231

RESUMO

We demonstrate a surface-emitting quantum cascade laser (QCL) based on second-order buried distributed feedback/distributed Bragg reflector (DFB/DBR) gratings for feedback and outcoupling. The grating fabricated beneath the waveguide was found to fundamentally favor lasing in symmetric mode either through analysis or experiment. Single-lobe far-field radiation pattern with full width at half maximum (FWHM) of 0.18° was obtained along the cavity-length direction. Besides, the buried DFB/DBR grating structure successfully provided an efficient vertical outcoupling mechanism with low optical losses, which manages to achieve a high surface outcouping efficiency of 46% in continuous-wave (CW) operation and 60% in pulsed operation at room temperature. Single-mode emission with a side-mode suppression ratio (SMSR) about 25 dB was continuously tunable by heat sink temperature or injection current. Our work contributes to the realization of high efficiency surface-emitting devices with high far-field beam quality that are significantly needed in many application fields.

5.
J Sci Food Agric ; 96(13): 4484-91, 2016 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26858003

RESUMO

BACKGROUND: Tricholoma mongolicum Imai is a well-known edible and medicinal mushroom which in recent years has attracted increasing attention because of its bioactivities. In this study, water-soluble polysaccharides were extracted from T. mongolicum Imai by cellulase-assisted extraction and their antioxidant activities were investigated. RESULTS: In order to improve the yield of polysaccharides, four variables, cellulase amount (X1 ), pH (X2 ), temperature (X3 ) and extraction time (X4 ), were investigated with a Box-Behnken design. The optimal conditions were predicted to be cellulase amount of 20 g kg(-1) , pH of 4.0, temperature of 50 °C and extraction time of 127 min, with a predicted polysaccharide yield of 190.1 g kg(-1) . The actual yield of polysaccharides under these conditions was 189.6 g kg(-1) , which matched the predicted value well. The crude polysaccharides were purified to obtain four fractions, and characterization of each was carried out. In addition, antioxidant properties of four polysaccharides assessed by 1,1-diphenyl-2-picryldydrazyl (DPPH) and hydroxyl radical-scavenging assays indicated that polysaccharides from T. mongolicum Imai (TMIPs) possessed antioxidant activity in a dose-dependent manner. CONCLUSION: TMIPs show moderate antioxidant activities in vitro. Therefore it is suggested that TMIPs are potential natural antioxidants for use in functional foods. © 2016 Society of Chemical Industry.


Assuntos
Antioxidantes/isolamento & purificação , Celulase/metabolismo , Misturas Complexas/isolamento & purificação , Aditivos Alimentares/isolamento & purificação , Carpóforos/química , Polissacarídeos Fúngicos/isolamento & purificação , Tricholoma/química , Algoritmos , Antioxidantes/análise , Antioxidantes/química , Antioxidantes/metabolismo , Sequência de Carboidratos , China , Misturas Complexas/biossíntese , Misturas Complexas/química , Aditivos Alimentares/análise , Aditivos Alimentares/química , Aditivos Alimentares/metabolismo , Alimentos em Conserva/análise , Alimentos em Conserva/economia , Sequestradores de Radicais Livres/análise , Sequestradores de Radicais Livres/química , Sequestradores de Radicais Livres/isolamento & purificação , Sequestradores de Radicais Livres/metabolismo , Carpóforos/metabolismo , Polissacarídeos Fúngicos/análise , Polissacarídeos Fúngicos/biossíntese , Polissacarídeos Fúngicos/química , Temperatura Alta , Concentração de Íons de Hidrogênio , Modelos Químicos , Peso Molecular , Estatística como Assunto , Fatores de Tempo , Tricholoma/metabolismo
6.
Opt Express ; 23(9): 11462-9, 2015 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-25969241

RESUMO

Metallic periodic structure in subwavelength scale offers an exciting way to couple light into surface plasmons (SPs), thus manipulating the properties of near-field optics. We show that subwavelength metallic grating (SMG) defined on the substrate side of substrate emitting quantum cascade lasers enables far-field improvement in mid-infrared spectrum. The SMG is designed to tailor the interaction of SPs with single mode transverse magnetic light. The experiment results are in good agreement with the simulated model. A far-field full width at half maximum (FWHM) divergence angle of 3.9 ° in the direction perpendicular to the laser waveguide layers is obtained, improved by a factor of 8.5 compared with traditional surface emitting device.

7.
Tumour Biol ; 35(2): 1251-61, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24037916

RESUMO

Our recent studies have shown that hypothermic microenvironment promotes tumor progression and that the molecular sensors for cold are the transient receptor potential (TRP) channels TRPM8 and TRPA1. To evaluate the contribution of TRPM8 and TRPA1 to cancer malignancy, we screened cell subpopulations from Lewis lung cancer (LLC) using limiting dilutions and Western blotting. We identified that LLC-1 cells express 3-fold more TRPM8 than TRPA1, LLC-2 cells express TRPM8 at levels similar to TRPA1, and LLC-3 cells express TRPM8 at one-third the level of TRPA1. LLC-2 cells showed greater adhesion, migration, invasiveness and resistance to hypothermia than LLC-1 and LLC-3 cells, although LLC-2 cells had a longer doubling time. TRPM8 or TRPA1 knockdown using siRNA promoted cell proliferation and decreased adhesion and invasiveness in LLC-2 cells. When assessed for UCP2 staining, LLC-1 cells showed increased staining compared to LLC-2 cells, both of which had more UCP2-positive cells than the LLC-3 subpopulation. In an autophagy assay, hypothermia induced substantially less autophagy in LLC-1 cells than in LLC-2 cells, which displayed decreased autophagy compared to LLC-3 cells. Moreover, mice injected with LLC-2 cells had significantly more spontaneous and experimental lung metastases and a shorter overall survival time than mice injected with LLC-1 or LLC-3 cells. Importantly, LLC-2 cells were also more resistant to activated spleen CTL and the chemotherapeutic drug doxorubicin than LLC-1 and LLC-3 cells in vitro. Collectively, our data suggest that TRPM8 induces UCP2 to trigger metabolic transformation, whereas TRPA1 induces autophagy during adverse conditions, and the combination of both genes contributes directly to an invasive phenotype in lung cancer.


Assuntos
Canais de Cálcio/genética , Carcinoma Pulmonar de Lewis/genética , Invasividade Neoplásica/genética , Proteínas do Tecido Nervoso/genética , Canais de Cátion TRPM/genética , Canais de Potencial de Receptor Transitório/genética , Animais , Canais de Cálcio/biossíntese , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Canais Iônicos/metabolismo , Camundongos , Proteínas Mitocondriais/metabolismo , Proteínas do Tecido Nervoso/biossíntese , RNA Interferente Pequeno , Canal de Cátion TRPA1 , Canais de Cátion TRPM/biossíntese , Canais de Potencial de Receptor Transitório/biossíntese , Proteína Desacopladora 2
8.
Zhongguo Zhong Yao Za Zhi ; 39(5): 879-84, 2014 Mar.
Artigo em Zh | MEDLINE | ID: mdl-25204183

RESUMO

OBJECTIVE: To observe the effect of alcohol extracts from Pharbitidis Semen on the proliferation and metastasis of Lewis lung cancer, and study its anti-tumor mechanism. METHOD: In vitro, MTT assay and scratch assay were adopted to detect the effect of alcohol extracts from Pharbitidis Semen on the proliferation and metastasis of Lewis lung cancer cells. The cell autophagy was detected by the acridine orange staining. The gap-junction intercellular communication (GJIC) was investigated by the fluorescent yellow transfer. The expression of aquaporin 1 (AQP1) was analyzed by the Western blotting. In vivo, the subcutaneous implant model and the experimental pulmonary metastasis model of Lewis lung cancer in mice were established to evaluate the anti-tumor and anti-metastasis effects of alcohol extract from Pharbitidis Semen. The serum carcinoembryonic antigen (CEA) and beta2 microglobulin (beta2-MG) of mice bearing Lewis lung cancer were detected by the electrochemiluminesence immunoassay. The expressions of lung AQP1 and Connexin 43 (Cx43) were examined by the immunohistochemical method. RESULT: In vitro, alcohol extracts from Pharbitidis Semen inhibited the cell proliferation in a dose-dependent matter, significantly prevented the cell migration, down-regulated AQP1 proteins of cells, promoted GJIC, and decreased the serum-free autophagy of tumor cells. In vivo, compared with untreated model mice, alcohol extracts from Pharbitidis Semen inhibited the tumor growth in a dose-dependent matter, prevented the tumor metastasis and prolonged the life span of mice bearing Lewis lung cancer, while decreasing serum CEA and beta2-MG of mice bearing Lewis lung cancer, enhancing the immumohistochemical staining intensity of Cx43 and weakening aquaporins AQP1 positive intensity. CONCLUSION: Alcohol extracts from Pharbitidis Semen could prevent the proliferation and metastasis in Lewis lung cancer cells. Its mechanism may be related to the promotion of GJIC and the down-regulation of AQP1.


Assuntos
Antineoplásicos/administração & dosagem , Carcinoma Pulmonar de Lewis/tratamento farmacológico , Medicamentos de Ervas Chinesas/administração & dosagem , Ipomoea/química , Neoplasias Pulmonares/tratamento farmacológico , Sementes/química , Animais , Aquaporina 1/genética , Aquaporina 1/metabolismo , Carcinoma Pulmonar de Lewis/genética , Carcinoma Pulmonar de Lewis/metabolismo , Carcinoma Pulmonar de Lewis/patologia , Linhagem Celular Tumoral , Conexina 43/genética , Conexina 43/metabolismo , Modelos Animais de Doenças , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Metástase Neoplásica
9.
Huan Jing Ke Xue ; 45(7): 4052-4062, 2024 Jul 08.
Artigo em Zh | MEDLINE | ID: mdl-39022953

RESUMO

Microplastics are among the most difficult new pollutants to remove in wastewater treatment plants. In order to explore the occurrence form, size distribution, composition, removal efficiency, migration law, and fate behavior characteristics of microplastic particles in sewage plants, taking a sewage treatment plant in Hohhot as an example, a total of 17 sampling sites were set up. The LAS X software counted the shape, abundance, and size of microplastics and conducted a full-process analysis. The results showed that: fibrous microplastics had the highest abundance and widest distribution and were the main form of existence, accounting for 61.8% of the total abundance; the size of microplastics ranged mainly between 0 and 1.00 mm, and among the four sizes, the abundance of microplastics 0.25 to 0.50 mm in China was the highest, accounting for 32.9%. Among the eight types of plastic components detected, polyester substances (PET, PBT), cellulose, and polypropylene (PP) were the main components, accounting for 25%, 21%, and 17%, respectively. The influent abundance of the sewage plant was (73 ±5) n·L-1, the effluent abundance was (14 ±2) n·L-1, and the overall removal rate was (80.8 ±12.1)%. Among the three treatment stages of the sewage plant, only the primary treatment played a role in removal, and the abundance of microplastics surged in the secondary treatment. Different structures playing a major role in the removal of microplastics were fine grids (49.2 ±7.4)% and secondary sedimentation tanks (92.4 ±13.9)%. Microplastics mainly existed in the form of fibers, fragments, and films. The proportion of fibers was approximately 70%, and the size of fragments was mainly concentrated between 0.50 and 5.00 mm. Most fragments were in the range of 5.00 mm, accounting for 50%, making them the main form apart from fibrous. The film-like size was mostly concentrated in the range of less than 0.50 mm, accounting for more than 10%. Therefore, improving the removal of small-sized fibrous and film-like microplastics and large-sized fragmented microplastic particles can effectively reduce the pollution risk of microplastics in the environment caused by sewage plant drainage.


Assuntos
Cidades , Microplásticos , Eliminação de Resíduos Líquidos , Águas Residuárias , Poluentes Químicos da Água , Microplásticos/análise , Eliminação de Resíduos Líquidos/métodos , Águas Residuárias/química , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/isolamento & purificação , China , Esgotos/química , Plásticos , Tamanho da Partícula , Polipropilenos , Monitoramento Ambiental
10.
Huan Jing Ke Xue ; 45(3): 1415-1427, 2024 Mar 08.
Artigo em Zh | MEDLINE | ID: mdl-38471857

RESUMO

To explore the spatial and temporal distribution characteristics of heavy metals in the surface sediments of lakes in cold regions during ice-sealing and non-ice-sealing periods, we analyzed the potential ecological risk degree and the pollution sources. A total of 20 sampling sites in Lake Ulansuhai in cold regions were collected from 2020 to 2021, and 120 surface sediment samples were collected during different periods. The contents of As, Cd, Cr, Cu, Ni, Pb, Zn, and Hg were determined. Correlation analysis, principal component analysis, and the absolute factor score-multiple linear regression (APCS-MLR) receptor model were used to trace the source of heavy metal pollution. The results showed that:① the distribution of heavy metals in lake surface sediments was different between the ice-sealing period and the non-ice-sealing period. The distribution of heavy metals during the ice-sealing period was higher in the north and lower in the south. Cd and Hg were mainly distributed in the central and southern lakes during the non-glacial period. ② Hg, Cd, and As were moderately polluted, and Ni was mildly polluted in the surface sediments of the lake. The overall performance was at a high risk level, and the pollution level during the non-ice-sealing period was higher than that during the ice-sealing period. The main environmental risk factors were Hg and Cd, which showed high risk and moderate risk, respectively. ③ The sources of heavy metals in lake surface sediments were mainly industrial sources from mining and transportation, agricultural sources, and natural sources. As, Ni, Pb, and Hg were mainly affected by industrial sources, with contribution rates of 62.67%, 75.31%, 77.47%, and 80.11%, respectively. The main sources of Cu and Zn were natural sources, and Cd was greatly affected by agricultural sources. The contribution rate was 81.57%. The source of Cr was mainly affected by natural factors, and the influence of human activities and unknown sources require further attention.

11.
Zhonghua Xin Xue Guan Bing Za Zhi ; 41(3): 219-23, 2013 Mar.
Artigo em Zh | MEDLINE | ID: mdl-23879947

RESUMO

OBJECTIVE: To observe the impact of systolic blood pressure (SBP) on visit-to-visit blood pressure variability (BPV) in middle-aged and elderly people. METHODS: Visit-to-visit BPV was determined in 5440 workers in the Kailuan study cohort from 2006 to 2007. The subjects were ≥ 40 years-old and had no history of stroke, transient ischemic attack or myocardial infarction. Participants were divided into five groups according to different levels of SBP. Linear regression was used to analyze the related factors which might affect BPV. RESULTS: Mean systolic BPV of all subjects was 10.35 mm Hg [coefficient of variation (CV 7.96%)]. The mean systolic BPV of males was 10.54 mm Hg (CV 7.90%) while the mean SBPV of females was 10.06 mm Hg (CV 7.90%). The BPV of males was significant higher than that of females (P < 0.001). CV of SBP was similar between males and females. Furthermore, higher SBP was associated with higher BPV. There were significant differences in BPV between different groups with different levels of SBP (P < 0.001). Linear regression analysis demonstrated that SBP, age, gender, high-sensitivity C-reactive protein (hsCRP) were affecting factors of BPV. Twenty mm Hg SBP increase was linked with 2.02 mm Hg BPV increase and 0.388%CV increase. Age increase of 1 year was associated with 0.044 mm Hg BPV increase and 0.029% CV increase. CONCLUSION: SBP, age, gender and hsCRP are important factors affecting BPV in middle-aged and elderly people. Higher SBP is closely related to greater BPV in this cohort.


Assuntos
Pressão Sanguínea/fisiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Monitorização Ambulatorial da Pressão Arterial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Análise de Regressão , Sístole
12.
Huan Jing Ke Xue ; 44(10): 5344-5355, 2023 Oct 08.
Artigo em Zh | MEDLINE | ID: mdl-37827753

RESUMO

To assess the health risk status and pollution sources of heavy metals in the atmosphere of ecologically vulnerable areas, the surrounding area of Dahekou Reservoir in Xilingol League was selected as the study area. From 2021 to 2022, 12 monitoring points for atmospheric dust fall were collected for a period of one year. A total of 144 samples were collected to determine the contents of eight types of heavy metals, namely Cr, Ni, Pb, Cu, Zn, Mn, As, and Cd. The potential ecological index (Eri) and health risk assessment model were used to assess the risk level of atmospheric heavy metals on ecological security and human health. The analysis of enrichment factors, principal components, and the model of absolute principal component multiple linear regression (APCS-MLR) receptor were used to analyze the sources of heavy metal pollution qualitatively in the atmosphere of the study area. The results showed that:① the mean value of the comprehensive potential ecological risk of heavy metals in the annual atmospheric dust fall in the study area was at a high ecological risk, and only the Cd value was at a very high risk level among the heavy metals, whereas the remaining were at a slight risk. ② The results of the health risk showed that intake by hand, mouth, and skin contact were the main exposure routes, which led to non-carcinogenic and carcinogenic risks. Children were under non-carcinogenic and acceptable carcinogenic risks in different months. During those months, the main source of the risks was As. ③ Through enrichment factor analysis, principal component analysis, and APCS-MLR receptor model calculation, the results revealed that the proportion of wind-blown sources was the largest, accounting for 37.82%, and the contribution rates of coal combustion and traffic sources to Cu, Cd, Pb, and Zn were 73.01%, 40.22%, 70.31%, and 32.82%, respectively. The contribution rate of mining activities to As was 42.59%, while that of industrial sources of Cd was 22.01%; the contributions of other human activity sources of Cd, As, Pb, and Zn were 21.12%, 34.40%, 23.04%, and 32.15%, respectively.


Assuntos
Poeira , Metais Pesados , Criança , Humanos , Poeira/análise , Monitoramento Ambiental , Modelos Lineares , Cádmio/análise , Chumbo/análise , Metais Pesados/análise , Medição de Risco , China
13.
RSC Adv ; 13(24): 16536-16548, 2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37274399

RESUMO

The development of environment-friendly and non-toxic green energetic materials and their safe, environmentally friendly, and economical production is very important to the national economy and national security. As an innovative, efficient, and environmentally friendly energetic material, the preferred preparation method of ammonium dinitramide (ADN) is the nitro-sulfur mixed acid method, which has the advantages of high yield, simple method, and easy access to raw materials. However, the large number of inorganic salt ions introduced by this method limits the large-scale production of ADN. Nanofiltration (NF) has been widely used in various industrial processes as a separation method with high separation efficiency and simple operation. In this study, NF was used for the desalination and purification of ADN synthesized by the mixed acid method. The effects of NF types, operation process (pressure, temperature, and feed solution concentration) on desalination efficiency, and membrane flux during purification were examined. The results showed that 600D NF could achieve the efficient desalination and purification of ADN. It was verified that the highest desalination and purification efficiency was achieved at 2 MPa pressure, 25 °C, and 1 time dilution of the feed solution, and the membrane flux of the desalination and purification process was stable. Under the optimized process conditions, the removal rate of inorganic salts and other impurities reached 99% (which can be recycled), the purity of ADN reached 99.8%, and the recovery rate reached 99%. This process has the potential for the large-scale production of ADN and provides a new process for the safe, efficient, and cheap preparation of energetic materials.

14.
J Phycol ; 47(3): 557-564, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27021985

RESUMO

Effects of ammonium on the photosynthetic recovery of Nostoc flagelliforme Berk. et M. A. Curtis were assayed when being rehydrated in low-K+ or high-K+ medium. Its photosynthetic recovery was K+ limited after 3 years of dry storage. The potassium absorption of N. flagelliforme reached the maximum after 3 h rehydration in low-K+ medium but at 5 min in high-K+ medium. The K+ content of N. flagelliforme rehydrated in high-K+ medium was much higher than that in low-K+ medium. The maximal PSII quantum yield (Fv /Fm ) value of N. flagelliforme decreased significantly when samples were rehydrated in low-K+ medium treated with 5 mM NH4 Cl. However, the treatment of 20 mM NH4 Cl had little effect on its Fv /Fm value in high-K+ medium. The relative Fv /Fm 24 h EC50 (concentration at which 50% inhibition occurred) value of NH4+ in high-K+ medium (64.35 mM) was much higher than that in low-K+ medium (22.17 mM). This finding indicated that high K+ could alleviate the inhibitory action of NH4+ upon the photosynthetic recovery of N. flagelliforme during rehydration. In the presence of 10 mM tetraethylammonium chloride (TEACl), the relative Fv /Fm 24 h EC50 value of NH4+ was increased to 46.34 and 70.78 mM, respectively, in low-K+ and high-K+ media. This observation suggested that NH4+ entered into N. flagelliforme cells via the K+ channel. Furthermore, NH4+ could decrease K+ absorption in high-K+ medium.

15.
Plant Cell Rep ; 30(9): 1683-99, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21638061

RESUMO

SnRK2 (sucrose non-fermenting 1-related protein kinases 2) represents a unique family of protein kinase in regulating signaling transduction in plants. Although the regulatory mechanisms of SnRK2 have been well demonstrated in Arabidopsis thaliana, their functions in maize are still unknown. In our study, we cloned an SnRK2 gene from maize, ZmSAPK8, which encoded a putative homolog of the rice SAPK8 protein. ZmSAPK8 had two copies in the maize genome and harbored eight introns in its coding region. We demonstrated that ZmSAPK8 expressed differentially in various organs of maize plants and was up-regulated by high-salinity and drought treatment. A green fluorescent protein (GFP)-tagged ZmSAPK8 showed subcellular localization in the cell membrane, cytoplasm and nucleus. In vitro kinase assays indicated that ZmSAPK8 preferred Mn(2+) to Mg(2+) as cofactor for phosphorylation, and Ser-182 and Thr-183 in activation loop was important for its activity. Heterologous overexpression of ZmSAPK8 in Arabidopsis could significantly strengthen tolerance to salt stress. Under salt treatment, ZmSAPK8-overexpressed transgenic plants exhibited higher germination rate and proline content, low electrolyte leakage and higher survival rate than wild type. Further analysis indicated that transgenic plants showed increased transcription of the stress-related genes, RD29A, RD29B, RAB18, ABI1, DREB2A and P5CS1, under high-salinity conditions. The results demonstrated that ZmSAPK8 was involved in diverse stress signal transduction. Moreover, no obvious adverse effects on growth and development in the ZmSAPK8-overexpressed transgenic plants implied that ZmSAPK8 was potentially useful in transgenic breeding to improve salt tolerance in crops.


Assuntos
Arabidopsis/genética , Proteínas Serina-Treonina Quinases/genética , Tolerância ao Sal , Zea mays/genética , Sequência de Aminoácidos , Arabidopsis/efeitos dos fármacos , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Clonagem Molecular , DNA Complementar/genética , Eletrólitos/metabolismo , Ativação Enzimática , Regulação da Expressão Gênica de Plantas , Genes de Plantas , Germinação , Manganês/metabolismo , Dados de Sequência Molecular , Mutagênese Sítio-Dirigida , Fosforilação , Filogenia , Plantas Geneticamente Modificadas/efeitos dos fármacos , Plantas Geneticamente Modificadas/genética , Plantas Geneticamente Modificadas/metabolismo , Plantas Geneticamente Modificadas/fisiologia , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Recombinantes de Fusão/metabolismo , Transdução de Sinais , Cloreto de Sódio/farmacologia , Estresse Fisiológico , Transcrição Gênica , Regulação para Cima , Zea mays/efeitos dos fármacos , Zea mays/metabolismo
16.
BMC Infect Dis ; 10: 178, 2010 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-20565813

RESUMO

BACKGROUND: EV71 is associated with the fatal cases of brain stem encephalitis during large HFMD outbreaks from 1998 to 2008. EV71 may continuously shed from upper respiratory tracts and feces of HFMD patients for relatively long time after recovery. However, the persistence of viruses in the patients' secretions and excretions is not clear. METHODS: Serial throat swabs and feces of 34 definitely diagnosed patients, including 30 mild cases and 4 severe cases, were traced and collected with the interval of 2 to 4 days for up to 32 and 48 days, respectively, and tested by a nested RT-PCR. RESULTS: The EV-71 specific sequences were identified by a Nested RT-PCR in all specimens of 0-4 days, and 5-8 days. The positive rates of EV71 in throat swabs dropped markedly to 42.86% during 9-12 days, and maintained at 20-30% during 13-24 days, while that in feces reduced to 71.43% during 9-12 days, and maintained roughly 20% till 37-40 days. EV71 nucleotide of 36.36% cases disappeared simultaneously both in throats and feces, 39.39% cases showed longer persistence of EV71 nucleotides in feces, and 21.21% were longer in throats. The longest duration of shedding observed was 24 days for throat swabs and 42 days for fecal specimens. CONCLUSIONS: EV71 shedding from respiratory tract may continue for nearly four weeks after onset, but its excretion through feces can persist more than five weeks.


Assuntos
Enterovirus Humano A/isolamento & purificação , Fezes/virologia , Doença de Mão, Pé e Boca/virologia , Faringe/virologia , RNA Viral/isolamento & purificação , Eliminação de Partículas Virais , Pré-Escolar , Enterovirus Humano A/genética , Feminino , Seguimentos , Humanos , Lactente , Masculino , Reação em Cadeia da Polimerase/métodos , Fatores de Tempo
17.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 28(1): 242-247, 2020 Feb.
Artigo em Zh | MEDLINE | ID: mdl-32027284

RESUMO

OBJECTIVE: To investigate the preventive and therapeutic effects of endothelial progenitor cells on monocrotaline-induced hepatic vein occlusion disease in mice. METHODS: C57BL/6 mice were randomly divided into 3 groups: saline group (n=15), monocrotaline group (n=15), and endothelial progenitor cell infusion group (n=15). Liver function (TBIL, ALT, AST), liver index, and serum levels of TNF-α and IL-6 were measured on the 8th day after intragastric administration. Hepatic sinusoidal endothelial cells, hepatic central venous endothelial cells and hepatocytes were observed by both HE and immunohistochemical staining. Hepatic fibrosis was observed by Masson's trichrome staining. RESULTS: By the light microscopy, the liver of the monocrotaline group showed moderate to the severe injuries of hepatic sinusoidal and central venous endothelial cells, and hepatic venous congestion. Masson staining showed moderate to severe hepatic fibrosis of central vein and hepatic sinus. In the endothelial progenitor cell group, hepatic sinusoidal and central venous endothelial cell injuries, and the fibrosis of central hepatic vein and hepatic sinus were mild to moderate. Hepatic venous congestion was reduced in comparison with that in the mice of the monocrotaline group. Compared with the endothelial progenitor cell group, the liver index was higher, the liver function was more abnormal, and the serum expression levels of TNF-α and IL-6 were higher in the monocrotaline group. CONCLUSION: The monocrotaline-induced damage of hepatic sinusoidal and central venous endothelial cells is an linitiating factor for hepatic vein occlusive disease. Infusion of endothelial progenitor cells can play a role in preventing and treating hepatic vein occlusion.


Assuntos
Células Progenitoras Endoteliais , Hepatopatia Veno-Oclusiva , Animais , Veias Hepáticas , Fígado , Camundongos , Camundongos Endogâmicos C57BL , Monocrotalina
18.
Zhonghua Yu Fang Yi Xue Za Zhi ; 43(4): 299-304, 2009 Apr.
Artigo em Zh | MEDLINE | ID: mdl-19534950

RESUMO

OBJECTIVE: To examine the relationship between prepregnancy body mass index (BMI) and the risk of pregnancy-induced hypertension (PIH) in Chinese population. METHODS: Data were collected in 6 counties/cities covered by Perinatal Health Care Surveillance System which was part of the Sino-American cooperative project on neural tube defects prevention established in 1992. The study population consisted of 83 159 women who attended premarital or preconception medical physical examination and delivered single live births with at least 20 gestational weeks from 1995 to 2000 in Jiaxing area. The Chi-square test was employed to test the difference in the rates of PIH among groups with different BMI. Multivariate logistic regression was conducted to examine the association between prepregnancy BMI and the risk of PIH. RESULTS: The rate of PIH was 11.01% (9153/83 159; 95% CI: 10.79% - 11.22%). The rate of PIH among women with BMI < 18.5 kg/m(2), 18.5 - 22.9 kg/m(2), 23.0 - 24.9 kg/m(2), and > or = 25.0 kg/m(2) were 9.08% (1405/15 472; 95% CI: 8.63% - 9.54%), 10.82% (6389/59 054; 95% CI: 10.57% - 11.07%), 14.63% (943/6444; 95% CI: 13.78% - 15.52%), and 19.00% (416/2189; 95% CI: 17.38% - 20.71%), respectively, the difference was significant (chi(trend)(2) = 261.028, P = 0.000). Taking those with BMI 18.5 - 22.9 kg/m(2) as reference, the unadjusted RR for PIH was 0.82 (95% CI: 0.77 - 0.87) among women with BMI < 18.5 kg/m(2), 1.41 (95% CI: 1.31 - 1.52) among women with BMI 23.0 - 24.9 kg/m(2), and 1.93 (95% CI: 1.73 - 2.16) among women with BMI > or = 25.0 kg/m(2). After controlling for area, maternal age at delivery, educational level, occupation, parity, times of prenatal visit as well as the individual or family history of chronic hypertension, the estimated RR were 0.85 (95% CI: 0.80 - 0.90), 1.37 (95% CI: 1.27 - 1.47) and 1.88 (95% CI: 1.68 - 2.10), respectively. CONCLUSION: High prepregnancy BMI could increase the risk of PIH.


Assuntos
Índice de Massa Corporal , Hipertensão Induzida pela Gravidez/epidemiologia , Adulto , Feminino , Humanos , Incidência , Modelos Logísticos , Gravidez , População Rural , População Urbana
19.
Exp Ther Med ; 17(6): 4617-4627, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31105790

RESUMO

The aim of the present study was to identify genes under the effect of transforming growth factor-ß (TGF-ß1), high glucose (HG) and glucosamine (GlcN) in MES-13 mesangial cells and elucidate the molecular mechanisms of diabetic nephropathy (DN). The gene expression datasets GSE2557 and GSE2558 were downloaded from the Gene Expression Omnibus database. Differentially expressed genes (DEGs) were independently screened using the GEO2R online tool. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the Database for Annotation, Visualization, and Integrated Discovery. The protein-protein interaction (PPI) network was constructed using the Search Tool for the Retrieval of Interacting Genes and Cytoscape software. The hub genes were identified by the NetworkAnalyzer plugin. Overlapping genes were subjected to molecular docking analysis using SystemsDock. A total of 202 upregulated and 158 downregulated DEGs from the HG-treated groups, 138 upregulated and 103 downregulated DEGs from the GlcN-treated groups, and 81 upregulated and 44 downregulated DEGs from the TGF-ß1-treated groups were identified. The majority of the DEGs were independently enriched in 'nucleosome assembly', 'chromatin silencing' and 'xenobiotic glucuronidation'. In addition, KEGG pathways were significantly enriched in 'systemic lupus erythematosus', 'protein processing in endoplasmic reticulum' and 'aldarate metabolism pathway', and 'TNF signaling pathway' intersected in the TGF-ß1-treated and HG-treated groups. In total, eight hub genes, Jun, prostaglandin-endoperoxide synthase 2 (Ptgs2), fibronectin 1 (Fn1), cyclin-dependent kinase (Cdk)2, Fos, heat shock protein family A (Hsp70) member 5 (Hspa5), Hsp90b1 and homo sapiens hypoxia upregulated 1 (Hyou1), and three overlapping genes, Ras homolog gene family, member B (RHOB), complement factor H (CFH) and Krüppel-like factor 15 (KLF15), were selected. Valsartan with RHOB, and fosinopril with CFH and KLF15 had preferential binding activity. In conclusion, Jun, Ptgs2, Fn1, Cdk2, Fos, Hspa5, Hsp90b1, Hyou1, RHOB, CFH and KLF15 may be potential therapeutic targets for mesangial cells associated with DN, which may provide insight into DN treatment strategies.

20.
J Biochem Mol Toxicol ; 22(6): 422-8, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19111004

RESUMO

Tripterygium glycosides (TG), extracted from the Chinese herb Tripterygium wilfordii Hook. f, is a widely used anti-inflammatory and immunosuppressive agent with definite nephrotoxicity. However, its toxic mechanism remained undiscovered. The aim of this study was to characterize the potential toxicity of TG on segments of proximal tubule in rats. Six hundred and 1200 mg/kg of TG was administered by daily intragastric instillation for 16 days. A significant reduction of p-aminohippurate accumulation by renal cortical slices indicated that TG damaged organic anion transporter (OAT) system that localized at the proximal tubule, especially S(2) segment. A dramatic loss of kidney glutamine synthetase (GS) activity induced by TG reflected S(3) segment damage. Because mRNA expression of OAT1, OAT3, and GS was decreased substantially, we ascribe the fall of p-aminohippurate accumulation and GS activity to alterations at the transcriptional level. A dose-related diminution of kidney glutathione S-transferase activity was noted simultaneously, suggesting oxidative stress involvement. Histopathological lesions were observed in the TG intoxicated rat kidney even though there were no obvious changes of serum urea and creatinine at this dose level. In summary, we provided evidences supporting that TG caused segment-specific dysfunction in the kidney proximal tubule.


Assuntos
Glicosídeos/toxicidade , Túbulos Renais Proximais/patologia , Tripterygium/química , Animais , Bioensaio , Creatinina/sangue , Regulação da Expressão Gênica/efeitos dos fármacos , Glutamato-Amônia Ligase/genética , Glutamato-Amônia Ligase/metabolismo , Túbulos Renais Proximais/enzimologia , Masculino , Especificidade de Órgãos/efeitos dos fármacos , Proteína 1 Transportadora de Ânions Orgânicos/genética , Proteína 1 Transportadora de Ânions Orgânicos/metabolismo , Transportadores de Ânions Orgânicos Sódio-Independentes/genética , Transportadores de Ânions Orgânicos Sódio-Independentes/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Ureia/sangue , Ácido p-Aminoipúrico/metabolismo
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