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1.
J Immunol ; 203(5): 1198-1207, 2019 09 01.
Article in English | MEDLINE | ID: mdl-31315888

ABSTRACT

It is increasingly recognized that excessive glucocorticoids induce fetal intrauterine growth restriction (IUGR). Placental 11ß-hydroxysteroid dehydrogenase 2 (11ß-HSD2), a glucocorticoid-catalyzing enzyme, prevents active glucocorticoids from maternal circulation into the fetus, thus protecting against IUGR. Previous studies demonstrated gestational LPS exposure caused fetal IUGR. The aim of the current study was to investigate the effects of LPS on 11ß-HSD2 in mice placentas and human placental trophoblasts. Pregnant ICR(CD-1) mice were i.p. injected with LPS (200 µg/kg) on gestational day 16. As expected, gestational LPS exposure downregulated 11ß-HSD2 in mice placentas. In vitro, LPS downregulated 11ß-HSD2 in human placental trophoblasts. Additional experiment showed that LPS, which activated NF-κB, suppressed rosiglitazone-induced activation of peroxisome proliferator-activated receptor-γ (PPARγ) in mice placentas and human placental trophoblasts. Moreover, NF-κB p65 knockdown and specific NF-κB inhibitor attenuated LPS-induced suppression of PPARγ nuclear translocation in human placental trophoblasts. In addition, NF-κB p65 knockdown attenuated LPS-induced downregulation of 11ß-HSD2 in human placental trophoblasts. Mechanically, LPS promoted physical interaction between NF-κB p65 and PPARγ in the cytoplasm and nucleus of placental trophoblasts. Finally, pretreatment with rosiglitazone, a PPARγ agonist, partially alleviated LPS-induced reduction of fetal weight and crown-rump length. Taken together, these results suggest that LPS downregulates 11ß-HSD2 through suppressing PPARγ in placental trophoblasts. Placental 11ß-HSD2 downregulation may contribute partially to LPS-induced fetal IUGR.


Subject(s)
11-beta-Hydroxysteroid Dehydrogenases/genetics , Lipopolysaccharides/toxicity , PPAR gamma/antagonists & inhibitors , Placenta/drug effects , Trophoblasts/drug effects , Active Transport, Cell Nucleus , Animals , Cells, Cultured , Down-Regulation , Female , Fetal Growth Retardation/chemically induced , Humans , Male , Mice , Mice, Inbred ICR , PPAR gamma/physiology , Placenta/enzymology , Pregnancy , Rosiglitazone/pharmacology , Transcription Factor RelA/antagonists & inhibitors , Transcription Factor RelA/physiology , Trophoblasts/enzymology
2.
Gynecol Endocrinol ; 35(9): 825-828, 2019 Sep.
Article in English | MEDLINE | ID: mdl-30990090

ABSTRACT

The aim of this study is to review the natural course, clinical features, and reproductive prognosis of ovarian tumors associated with hyperandrogenemia. We retrospect 33 patients of ovarian tumors with hyperandrogenemia. Thirty cases (91%) were sex cord-stromal tumors. Sertoli-Leydig cell tumors, Leydig cell tumors, and steroid cell tumors were the most common types. It is not possible, to predict the pathological subtypes based on androgen levels alone. Most of these tumors were solid masses, with an average diameter of 3.9 cm. These tumors are soft or fragile, no clear boundary with normal tissue, thus excision is superior to exfoliation. The average disease course of the top three tumors was 32.6, 35.4, and 67.7 months, respectively. Among 11 married women with a desire to get pregnant, nine cases resumed menstrual periods after surgery and became pregnant naturally. Hyperandrogenemia might predict a better prognosis. The asynchronism of hyperandrogenemia and undetectable tumor may cause irreversible change and emotional depress, the methods of early diagnosis need further study.


Subject(s)
Hyperandrogenism/complications , Hyperandrogenism/diagnosis , Ovarian Neoplasms/complications , Ovarian Neoplasms/diagnosis , Sex Cord-Gonadal Stromal Tumors/complications , Sex Cord-Gonadal Stromal Tumors/diagnosis , Adolescent , Adult , Aged , Androgens/blood , Biomarkers, Tumor/analysis , Biomarkers, Tumor/metabolism , Child , Child, Preschool , Disease Progression , Female , Fertility Preservation , Humans , Hyperandrogenism/pathology , Hyperandrogenism/surgery , Middle Aged , Ovarian Neoplasms/pathology , Ovarian Neoplasms/surgery , Prognosis , Retrospective Studies , Sertoli-Leydig Cell Tumor/complications , Sertoli-Leydig Cell Tumor/diagnosis , Sertoli-Leydig Cell Tumor/pathology , Sertoli-Leydig Cell Tumor/surgery , Sex Cord-Gonadal Stromal Tumors/pathology , Sex Cord-Gonadal Stromal Tumors/surgery , Tumor Burden , Young Adult
3.
J Immunol ; 197(12): 4762-4770, 2016 12 15.
Article in English | MEDLINE | ID: mdl-27821667

ABSTRACT

Farnesoid X receptor (FXR) is expressed in human and rodent placentas. Nevertheless, its function remains obscure. This study investigated the effects of obeticholic acid (OCA), a novel synthetic FXR agonist, on LPS-induced fetal death and intrauterine growth restriction. All pregnant mice except controls were i.p. injected with LPS (100 µg/kg) daily from gestational day (GD) 15 to GD17. Some pregnant mice were orally administered with OCA (5 mg/kg) daily from GD13 to GD17. As expected, placental FXR signaling was activated by OCA. OCA pretreatment protected against LPS-induced fetal death. In addition, OCA pretreatment alleviated LPS-induced reduction of fetal weight and crown-rump length. Additional experiments showed that OCA inhibited LPS-evoked TNF-α in maternal serum and amniotic fluid. Moreover, OCA significantly attenuated LPS-induced upregulation of placental proinflammatory genes including Tnf-α, Il-1ß, IL-6, Il-12, Mip-2, Kc, and Mcp-1 By contrast, OCA elevated anti-inflammatory cytokine IL-10 in maternal serum, amniotic fluid, and placenta. Further analysis showed that OCA blocked nuclear translocation of NF-κB p65 and p50 subunits in trophoblast giant cells of the labyrinth zone. These results provide a mechanistic explanation for placental FXR-mediated anti-inflammatory activity. Overall, this study provides evidence for roles of FXR as an important regulator of placental inflammation.


Subject(s)
Anti-Inflammatory Agents/administration & dosage , Chenodeoxycholic Acid/analogs & derivatives , Endotoxemia/complications , Fetal Death/prevention & control , Fetal Growth Retardation/prevention & control , Placenta/drug effects , Receptors, Cytoplasmic and Nuclear/metabolism , Animals , Anti-Inflammatory Agents/pharmacology , Chenodeoxycholic Acid/administration & dosage , Chenodeoxycholic Acid/pharmacology , Cytokines/metabolism , Endotoxemia/immunology , Female , Fetal Death/etiology , Fetal Growth Retardation/etiology , Humans , Inflammation Mediators/metabolism , Lipopolysaccharides/immunology , Male , Mice, Inbred ICR , NF-kappa B/metabolism , Placenta/immunology , Pregnancy , Receptors, Cytoplasmic and Nuclear/agonists , Signal Transduction
4.
Pak J Pharm Sci ; 31(3(Special)): 1137-1140, 2018 May.
Article in English | MEDLINE | ID: mdl-29735463

ABSTRACT

Antimicrobial agents are widely used in gynecologic inflammation and surgical period, so as to cure some infectious diseases, reduce the chance of surgical incision infection, but at the same time, there are many adverse reactions. The use of nursing interventions in obstetrics and gynecology can significantly reduce the adverse drug reactions in the treatment. The results showed that the incidence of adverse reactions in the observation group was 8.8%, while that in the control group was 15.6%. The incidence of adverse reactions in the observation group was significantly lower than that in the control group (P<0.05). The results showed that the nursing intervention in obstetrics and gynecology could reduce the adverse drug reactions. In a word, the nursing intervention of obstetrics and gynecology can greatly reduce the adverse reaction of antibiotics and has certain application value. It is worth popularizing in clinical practice.


Subject(s)
Anti-Bacterial Agents/adverse effects , Gynecologic Surgical Procedures , Obstetric Surgical Procedures , Postoperative Complications/chemically induced , Anti-Bacterial Agents/administration & dosage , Drug Hypersensitivity/prevention & control , Humans , Postoperative Complications/prevention & control
5.
Small ; 12(46): 6332-6337, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27670846

ABSTRACT

A protocol to quantify the distribution of surface atoms of concave nanocatalysts according to their coordination number is proposed. The 3D surface of an Au@Pd concave nanocube is reconstructed and segmented. The crystallographic coordinates and low-coordinate surface atom densities of the concave facets are determined. The result shows that 32% of the surface atoms are low-coordinated, which may contribute to the high activity.

6.
J Cardiovasc Pharmacol ; 67(1): 47-56, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26322923

ABSTRACT

AIMS: We recently reported that immunosuppression with FTY720 improves cardiac function and extends longevity in Hypomorphic ApoE mice deficient in scavenger receptor Type-BI expression, also known as the HypoE/SR-BI(­/­) mouse model of diet-induced coronary atherosclerosis and myocardial infarction (MI). In this study, we tested the impact of FTY720 on cardiac dysfunction in HypoE/SR-BI(­/­) mice that survive MI and subsequently develop chronic heart failure. METHODS/RESULTS: HypoE/SR-BI(­/­) mice were bred to Mx1-Cre transgenic mice, and offspring were fed a high-fat diet (HFD) for 3.5 weeks to provoke hyperlipidemia, coronary atherosclerosis, and recurrent MIs. In contrast to our previous study, hyperlipidemia was rapidly reversed by inducible Cre-mediated gene repair of the HypoE allele and switching mice to a normal chow diet. Mice that survived the period of HFD were subsequently given oral FTY720 in drinking water or not, and left ventricular (LV) function was monitored using serial echocardiography for up to 15 weeks. In untreated mice, LV performance progressively deteriorated. Although FTY720 treatment did not initially prevent a decline of heart function among mice 6 weeks after Cre-mediated gene repair, it almost completely restored normal LV function in these mice by 15 weeks. Reversal of heart failure did not result from reduced atherosclerosis as the burden of aortic and coronary atherosclerosis actually increased to similar levels in both groups of mice. Rather, FTY720 caused systemic immunosuppression as assessed by reduced numbers of circulating T and B lymphocytes. In contrast, FTY720 did not enhance the loss of T cells or macrophages that accumulated in the heart during the HFD feeding period, but it did enhance the loss of B cells soon after plasma lipid lowering. Moreover, FTY720 potently reduced the expression of matrix metalloproteinase-2 and genes involved in innate immunity-associated inflammation in the heart. CONCLUSIONS: Our data demonstrate that immunosuppression with FTY720 prevents postinfarction myocardial remodeling and chronic heart failure.


Subject(s)
Apolipoproteins E/deficiency , Coronary Artery Disease/drug therapy , Fingolimod Hydrochloride/therapeutic use , Immunosuppressive Agents/therapeutic use , Myocardial Infarction/drug therapy , Scavenger Receptors, Class B/biosynthesis , Animals , Coronary Artery Disease/metabolism , Coronary Artery Disease/mortality , Diet, High-Fat/adverse effects , Gene Expression Regulation , Mice , Mice, Transgenic , Myocardial Infarction/metabolism , Myocardial Infarction/mortality , Survival Rate/trends
7.
Biomed Environ Sci ; 28(12): 855-63, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26777905

ABSTRACT

OBJECTIVE: To develop a multiple-locus variable-number tandem-repeat (VNTR) analysis (MLVA) assay for Acinetobacter pittii typing. METHODS: Polymorphic VNTRs were searched by Tandem Repeats Finder. The distribution and polymorphism of each VNTR locus were analyzed in all the A. pittii genomes deposited in the NCBI genome database by BLAST and were evaluated with a collection of 20 well-characterized clinical A. pittii strains and one reference strain. The MLVA assay was compared with pulsed-field gel electrophoresis (PFGE) for discriminating A. pittii isolates. RESULTS: Ten VNTR loci were identified upon bioinformatic screening of A. pittii genomes, but only five of them showed full amplifiability and good polymorphism. Therefore, an MLVA assay composed of five VNTR loci was developed. The typeability, reproducibility, stability, discriminatory power, and epidemiological concordance were excellent. Compared with PFGE, the new optimized MLVA typing scheme provided the same and even greater discrimination. CONCLUSION: Compared with PFGE, MLVA typing is a faster and more standardized alternative for studying the genetic relatedness of A. pittii isolates in disease surveillance and outbreak investigation.


Subject(s)
Acinetobacter/classification , DNA Fingerprinting/methods , Acinetobacter/genetics , Electrophoresis, Gel, Pulsed-Field , Minisatellite Repeats , Polymerase Chain Reaction
8.
J Am Chem Soc ; 136(17): 6326-32, 2014 Apr 30.
Article in English | MEDLINE | ID: mdl-24730979

ABSTRACT

Copper and its salts are abundant, inexpensive, and eco-friendly and have been used as the surrogates of noble metals to effect arene C-H bond activation and transformations. Despite of the recent significant progress of the study, syntheses of high-valent arylcopper(II-III) compounds are still very rare and mechanisms of copper(II)-catalyzed reactions remain elusive. With the use of azacalix[1]arene[3]pyridines as a platform, a number of arylcopper(II) compounds were synthesized efficiently from the reaction of Cu(ClO4)2 under ambient conditions. The resulting aryl-Cu(II) compounds, which contain an unprecedented (substituted) phenyl-Cu(II) σ-bond, were stable under atmospheric conditions and can undergo facile oxidation reaction by free copper(II) ions or oxone to afford arylcopper(III) compounds in good yields. Both arylcopper(II) and arylcopper(III) compounds were characterized unambiguously by means of XRD, XPS, and NMR methods. Experimental evidence including reaction kinetics, LFER and KIE, and theoretical calculations indicated that the Cu(ClO4)2-mediated arene C-H bond activation proceeds plausibly through an electrophilic aromatic metalation pathway. The synthesis of high-valent arylcopper compounds and the reaction mechanism reported here highlight the diversity and richness of organocopper chemistry.


Subject(s)
Copper/chemistry , Hydrocarbons, Aromatic/chemical synthesis , Pyridines/chemistry , Catalysis , Crystallography, X-Ray , Hydrocarbons, Aromatic/chemistry , Kinetics , Models, Molecular , Oxidation-Reduction , Perchlorates/chemistry , Pyridines/chemical synthesis
9.
J Cardiovasc Pharmacol ; 63(2): 132-143, 2014 Feb.
Article in English | MEDLINE | ID: mdl-24508946

ABSTRACT

FTY720, an analogue of sphingosine-1-phosphate, is cardioprotective during acute injury. Whether long-term FTY720 affords cardioprotection is unknown. Here, we report the effects of oral FTY720 on ischemia/reperfusion injury and in hypomorphic apoE mice deficient in SR-BI receptor expression (ApoeR61(h/h)/SRB1(-/- mice), a model of diet-induced coronary atherosclerosis and heart failure. We added FTY720 (0.3 mg·kg(-1)·d(-1)) to the drinking water of C57BL/6J mice. After ex vivo cardiac ischemia/reperfusion injury, these mice had significantly improved left ventricular (LV) developed pressure and reduced infarct size compared with controls. Subsequently, ApoeR61(h/h)/SRB1(-/-) mice fed a high-fat diet for 4 weeks were treated or not with oral FTY720 (0.05 mg·kg(-1)·d(-1)). This sharply reduced mortality (P < 0.02) and resulted in better LV function and less LV remodeling compared with controls without reducing hypercholesterolemia and atherosclerosis. Oral FTY720 reduced the number of blood lymphocytes and increased the percentage of CD4+Foxp3+ regulatory T cells (Tregs) in the circulation, spleen, and lymph nodes. FTY720-treated mice exhibited increased TGF-ß and reduced IFN-γ expression in the heart. Also, CD4 expression was increased and strongly correlated with molecules involved in natural Treg activity, such as TGF-ß and GITR. Our data suggest that long-term FTY720 treatment enhances LV function and increases longevity in mice with heart failure. These benefits resulted not from atheroprotection but from systemic immunosuppression and a moderate reduction of inflammation in the heart.


Subject(s)
Apolipoproteins E/genetics , Coronary Artery Disease/drug therapy , Myocardial Infarction/drug therapy , Propylene Glycols/pharmacology , Sphingosine/analogs & derivatives , Animals , Cardiotonic Agents/administration & dosage , Cardiotonic Agents/pharmacology , Coronary Artery Disease/physiopathology , Diet, High-Fat/adverse effects , Disease Models, Animal , Fingolimod Hydrochloride , Immunosuppressive Agents/administration & dosage , Immunosuppressive Agents/pharmacology , Inflammation/drug therapy , Inflammation/etiology , Inflammation/physiopathology , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Myocardial Infarction/physiopathology , Myocardial Reperfusion Injury/drug therapy , Myocardial Reperfusion Injury/physiopathology , Propylene Glycols/administration & dosage , Sphingosine/administration & dosage , Sphingosine/pharmacology , Survival Rate , T-Lymphocytes, Regulatory/metabolism , Time Factors , Transforming Growth Factor beta/metabolism , Ventricular Function, Left/drug effects
11.
Blood Press ; 23(6): 339-44, 2014 Dec.
Article in English | MEDLINE | ID: mdl-24905962

ABSTRACT

In this study, we report the relationship between hyperuricemia and hypertension in a middle-aged Chinese population, emphasizing the difference of gender. The cross-sectional study was conducted among 1776 adults aged 45-60 years, who participated in the Hefei Nutrition and Health Study (2012). Hyperuricemia was defined as serum uric acid (SUA)> 420 µmol/l for men, and > 360 µmol/l for women. Hypertension was defined as systolic blood pressure (SBP) ≥ 140 mmHg or diastolic blood pressure (DBP) ≥ 90 mmHg. Anthropometric measurements and biochemical data were collected using standardized procedures. Multivariate logistic regression analysis was performed to determine the relationship between hyperuricemia and hypertension with adjustment of potential confounding factors. Body mass index (BMI), waist circumference (WC), SBP, DBP, fasting glucose, SUA and the prevalence of hyperuricemia and hypertension were significantly higher in male than in female (p < 0.001). Females had significantly higher levels of triglycerides (TG) and high-density lipoprotein (HDL)-cholesterol (5.23 ± 0.87 vs 5.12 ± 1.01, p < 0.05, 1.50 ± 0.37 vs 1.28 ± 0.41, respectively.) than males. Simple correlation analysis showed that SUA was positively associated with WC and TG. In addition, after adjusting for potential confounders, hyperuricemia was associated with increased risk of hypertension in both males and females, with odds ratios (95% CI) of 1.680 (1.110-2.543) and 1.065 (1.012-1.118), respectively. Conclusions: The association of hyperuricemia with hypertension was stronger in males than in females, and middle-aged men with hyperuricemia had greater association with hypertension. Our findings remain to be confirmed in future prospective studies.


Subject(s)
Hypertension/complications , Hyperuricemia/complications , Asian People , Body Mass Index , China/epidemiology , Cross-Sectional Studies , Female , Humans , Hypertension/blood , Hypertension/diagnosis , Hypertension/epidemiology , Hyperuricemia/blood , Hyperuricemia/diagnosis , Hyperuricemia/epidemiology , Lipoproteins, HDL/blood , Male , Middle Aged , Sex Factors , Triglycerides/blood , Uric Acid/blood , Waist Circumference
12.
Huan Jing Ke Xue ; 44(3): 1602-1610, 2023 Mar 08.
Article in Zh | MEDLINE | ID: mdl-36922221

ABSTRACT

In order to clarify the spatial distribution characteristics and the present situation of heavy metal pollution in cultivated soil of a typical mining basin in southern China, the contents of Cd, As, Mn, Cu, Zn, and Pb in cultivated soil in the selected small watershed were determined, and the spatial distribution characteristics of heavy metals were analyzed using the spatial interpolation method. Further, the ecological risk was evaluated using the geo-accumulation index and potential ecological risk coefficient (PERC). The results showed that the average contents of Pb, Zn, Cu, As, and Cd in the topsoil (0-20 cm) in the small watershed were approximately 11.9, 3.8, 8.2, 4.7, and 14.2 times that of the background value in Hunan soil, respectively. Compared with the soil risk screening value of agricultural land, the over-standard rates of Pb, Zn, Cu, As, and Cd were approximately 24%, 56%, 75%, 44%, and 48%, respectively. Zn and Mn showed medium variation, whereas Pb, As, Cu, and Cd showed strong variation, which indicated that there was an obvious enrichment of heavy metals in the small watershed. The spatial analysis results showed that there was an obvious consistent characteristic of six heavy metals in the topsoil, that is, there was enrichment in the mining activity area and its downstream and the township streets in the west of the small watershed. Additionally, there were high value points of some heavy metals on both sides of the main river, indicating that the main pollution sources in the study area were mining and metallurgy activities and sewage irrigation. The results of the geo-accumulation index and potential ecological risk index showed that there was compound pollution of heavy metals, in which the degree of Cd pollution was the highest, and the soil of both sides of the river could pose the strongest potential ecological risk.

13.
Huan Jing Ke Xue ; 44(1): 436-443, 2023 Jan 08.
Article in Zh | MEDLINE | ID: mdl-36635831

ABSTRACT

A strain of Enterobacter was screened from cadmium and arsenic contaminated farmland soil and its passivation mechanism of cadmium and arsenic were explored through removing performance and characterization experiments. The results showed that the screened strain M5 was identified as Enterobacter sp. with a sulfate-reduction function, and its maximum resistance concentration was approximately 1 mmol·L-1 to cadmium and arsenic. In the simulation system, the maximum removal efficiencies of cadmium and arsenic were 94.13% and 27.26% by strain M5, respectively. The results of SEM-EDS and XRD confirmed that Cd and As were fixed to CdS and As2S3, and XPS results showed that carboxyl groups, hydroxyl groups, and amide groups on the surface of the bacteria were mainly involved in biological adsorption. These results can provide new ideas and a theoretical basis for microbial applications to soil remediations for heavy metal pollution.


Subject(s)
Arsenic , Soil Pollutants , Cadmium/analysis , Enterobacter , Farms , Soil Pollutants/analysis , Soil , Biodegradation, Environmental
14.
Huan Jing Ke Xue ; 44(12): 7036-7044, 2023 Dec 08.
Article in Zh | MEDLINE | ID: mdl-38098426

ABSTRACT

The aim of this study was to explore the effects of different sulfur fertilizers combined with sulfate-reducing bacteria on the accumulation of cadmium and arsenic in rice and the formation of iron plaque under long-term flooding conditions and to provide a reference for the safe production of rice fields polluted by moderate and mild cadmium and arsenic. We adopted a pot experiment, selecting two sulfur fertilizers, sulfur and calcium sulfate, and Enterobacter M5 with sulfate-reducing ability, and designed six treatments of single application and combined application of different sulfur fertilizers and M5. The results showed that the combined application of calcium sulfate and M5(CM5) had the best effect on reducing available cadmium and arsenic in rice rhizosphere soil. The combined application of sulfur fertilizer or M5 could reduce the content of cadmium and inorganic arsenic in early season rice grains by 8%-51% and 42%-61%, respectively, under flooding conditions. The content of cadmium and inorganic arsenic in late rice grains decreased by 81%-92% and 41%-62%, respectively. The treatment of the combined application of sulfur and M5(SM5) and CM5 had the best effect on reducing cadmium and arsenic content in both early and late season rice grains. SM5 and CM5 could promote the adsorption of cadmium and arsenic by iron plaque, and the extracted cadmium and arsenic content of ACA in both treatments was significantly higher than that of CK. The extracted iron content of ACA in the CM5 treatment was also significantly higher than that of CK, which indicates that the combined application of calcium sulfate and M5 would promote the formation of iron plaque. The results showed that the combined application of sulfur fertilizer and M5 was better than single application in reducing the content of cadmium and arsenic in grains, whereas the combined application of calcium sulfate and M5 was the best and most stable method.


Subject(s)
Arsenic , Oryza , Soil Pollutants , Arsenic/analysis , Fertilizers/analysis , Enterobacter , Cadmium/analysis , Calcium Sulfate , Soil Pollutants/analysis , Iron , Sulfates , Sulfur , Soil
15.
Nanotechnology ; 23(49): 495710, 2012 Dec 14.
Article in English | MEDLINE | ID: mdl-23149673

ABSTRACT

Nearly monodisperse Au nanorods (NRs) with different aspect ratios were separated from home-synthesized polydisperse samples using a gradient centrifugation method. The morphology, size and its distribution, and photo-absorption property were analyzed by transmission electron microscopy, atomic force microscopy and UV-visible spectroscopy. Subsequently, using colloidal Au NRs (36.2 nm ×10.7 nm) with 97.4% yield after centrifugation and Au nanospheres (NSs) (22.9 ± 1.0 nm in diameter) with 97.6% yield as Au substrates, surface-enhanced Raman scattering (SERS) spectra of 2,4-dichlorophenoxyacetic acid (2,4-D) were recorded using laser excitation at 632.8 nm. Results show that surface enhancement factors (EF) for Au NRs and NSs are 6.2 × 10(5) and 5.7 × 10(4) using 1.0 × 10(-6) M 2,4-D, respectively, illustrating that EF value is a factor of ~10 greater for Au NRs substrates than for Au NSs substrates. As a result, large EF are a mainly result of chemical enhancement mechanisms. Thus, it is expected that Au NPs can find a comprehensive SERS application in the trace detection of pesticide residues.


Subject(s)
2,4-Dichlorophenoxyacetic Acid/analysis , Gold/chemistry , Metal Nanoparticles/chemistry , Spectrum Analysis, Raman/instrumentation , Transducers , 2,4-Dichlorophenoxyacetic Acid/chemistry , Equipment Design , Equipment Failure Analysis , Herbicides/analysis , Light , Scattering, Radiation
16.
Cancer Cell ; 4(3): 191-6, 2003 Sep.
Article in English | MEDLINE | ID: mdl-14522253

ABSTRACT

Exposure to second hand smoke (SHS) is believed to cause lung cancer. Pathological angiogenesis is a requisite for tumor growth. Lewis lung cancer cells were injected subcutaneously into mice, which were then exposed to sidestream smoke (SHS) or clean room air and administered vehicle, cerivastatin, or mecamylamine. SHS significantly increased tumor size, weight, capillary density, VEGF and MCP-1 levels, and circulating endothelial progenitor cells (EPC). Cerivastatin (an inhibitor of HMG-coA reductase) or mecamylamine (an inhibitor of nicotinic acetylcholine receptors) suppressed the effect of SHS to increase tumor size and capillary density. Cerivastatin reduced MCP-1 levels, whereas mecamylamine reduced VEGF levels and EPC. These studies reveal that SHS promotes tumor angiogenesis and growth. These effects of SHS are associated with increases in plasma VEGF and MCP-1 levels, and EPC, mediated in part by isoprenylation and nicotinic acetylcholine receptors.


Subject(s)
Carcinoma, Lewis Lung/etiology , Neovascularization, Pathologic/etiology , Nicotine/toxicity , Tobacco Smoke Pollution/adverse effects , Animals , Carcinoma, Lewis Lung/blood supply , Chemokine CCL2/metabolism , Endothelial Cells/metabolism , Hydroxymethylglutaryl CoA Reductases/metabolism , Mecamylamine/metabolism , Mice , Pyridines/metabolism , Receptors, Nicotinic/metabolism , Vascular Endothelial Growth Factor A/metabolism
17.
Cell Discov ; 8(1): 47, 2022 May 20.
Article in English | MEDLINE | ID: mdl-35595746

ABSTRACT

The endogenous cyclic tetradecapeptide SST14 was reported to stimulate all five somatostatin receptors (SSTR1-5) for hormone release, neurotransmission, cell growth arrest and cancer suppression. Two SST14-derived short cyclic SST analogues (lanreotide or octreotide) with improved stability and longer lifetime were developed as drugs to preferentially activate SSTR2 and treat acromegalia and neuroendocrine tumors. Here, cryo-EM structures of the human SSTR2-Gi complex bound with SST14, octreotide or lanreotide were determined at resolutions of 2.85 Å, 2.97 Å, and 2.87 Å, respectively. Structural and functional analysis revealed that interactions between ß-turn residues in SST analogues and transmembrane SSTR2 residues in the ligand-binding pocket are crucial for receptor binding and functional stimulation of the two SST14-derived cyclic octapeptides. Additionally, Q1022.63, N2766.55, and F2947.35 could be responsible for the selectivity of lanreotide or octreotide for SSTR2 over SSTR1 or SSTR4. These results provide valuable insights into further rational development of SST analogue drugs targeting SSTR2.

18.
J Gen Virol ; 92(Pt 3): 681-91, 2011 Mar.
Article in English | MEDLINE | ID: mdl-21084496

ABSTRACT

Hepatitis B virus infection (HBV) is a major medical problem in China. The lack of a suitable infection model in China is recognized as an obstacle for research on HBV in China. Chinese Marmota-species is phylogenetically closely related to Marmota monax, thus, it might be suitable to serve as an animal model for HBV infection. Therefore, we attempted to prove the claim about the existence of woodchuck hepatitis virus (WHV)-like viruses in Chinese Marmota-species and to determine the susceptibility of these species to experimental WHV infection. In the present study, 653 sera from three Chinese Marmota-species, Marmota himalayana, Marmota baibacina and Marmota bobak, were screened for WHV-like viruses by serological and molecular assays. The susceptibility to WHV of three species was investigated by experimental infection and monitored by testing of anti-WHc and WHsAg by ELISA, detection of WHV DNA by PCR, and detection of WHV replication intermediates and antigens in liver samples. No evidence for the existence of a genetically closely related virus to WHV in three Chinese Marmota-species was found by serological assays and PCR. M. himalayana was susceptible to WHV infection as inoculated animals became positive for anti-WHc, WHsAg and WHV DNA. Further, WHV replication intermediates and proteins were detected in liver samples. In contrast, M. baibacina remained negative for tested virological parameters. M. bobak species showed a limited susceptibility to WHV. Our data do not support early reports about WHV-like viruses in China. M. himalayana is suitable for the establishment of a model for hepadnaviral infection.


Subject(s)
Disease Models, Animal , Hepatitis B Virus, Woodchuck/pathogenicity , Hepatitis B/pathology , Hepatitis B/virology , Marmota/virology , Animals , China , DNA, Viral/analysis , DNA, Viral/blood , Hepatitis B Surface Antigens/analysis , Hepatitis B Surface Antigens/blood , Liver/virology , Serum/virology
19.
Phys Chem Chem Phys ; 13(9): 3863-72, 2011 Mar 07.
Article in English | MEDLINE | ID: mdl-21210027

ABSTRACT

Pt(m)^Ag nanostructures (m being the atomic Pt/Ag ratio, m = 0.1-0.6) were prepared by reflux citrate reduction of PtCl(6)(2-) ions in aqueous solution containing colloidal Ag (6.3 ± 3.9 nm). A distinct alloying of Pt with Ag was detected due to an involvement of the galvanic replacement reaction between PtCl(6)(2-) and metallic Ag colloids. The nanostructure transformed from a structure with an Ag-core and an alloyed PtAg-shell to a hollow PtAg alloy structure with the increase in m. Compared to a commercial E-TEK Pt/C catalyst, the catalytic performance of Pt in the Pt(m)^Ag/C samples for the cathode oxygen reduction reaction (ORR) strongly correlated with the electronic structure of Pt, as a consequence of varied Pt dispersion and Pt-Ag interaction. With either H(2)SO(4) or KOH as an electrolyte, Pt in the Pt(m)^Ag nanostructures with a relatively high m (≥0.4) showed significantly enhanced intrinsic activity whereas Pt in those catalysts with low m (≤0.2) appeared less active than the Pt/C catalyst. These data are used to discuss the role of electronic structure and geometric effects of Pt toward ORR.

20.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 33(6): 615-9, 2011 Dec.
Article in Zh | MEDLINE | ID: mdl-22509542

ABSTRACT

OBJECTIVE: To study the role of extracellular signal-regulated protein kinase 5 (ERK5) during the biosynthesis of follicle-stimulating hormone (FSH)-mediated progesterone in primary granulosa cells. METHODS: The expressions of phosphorylated and general forms of ERKS in primary granulosa cells after the treatment of FSH were detected by Western blot analysis. The subcellular localization of ERK5 was observed by confocal microscopy. The effect of ERK5 on FSH-mediated progesterone biosynthesis in primary granulosa cells was analyzed using recombinant adenovirus vectors. RESULTS: ERK5 activation was induced by FSH in a time-dependent manner in primary cultured granulosa cells, although the general ERK5 protein level decreased also in a time-dependent manner. The treatment of FSH showed no remarkable effect on the subcellular distribution of endogenous ERK5, which was mainly in the cytoplasm of granulosa cells. The co-infection of Ad-caMEK5 and Ad-wtERK5 increased the progesterone production and StAR expression in primary cultured granulosa cells, whereas inhibition of ERK5 activation suppressed the FSH-stimulated progesterone production. CONCLUSION: ERK5 may stimulate FSH-mediated progesterone production in primary cultured granulosa cells.


Subject(s)
Granulosa Cells/metabolism , Mitogen-Activated Protein Kinase 7/physiology , Progesterone/biosynthesis , Animals , Cells, Cultured , Female , Follicle Stimulating Hormone/pharmacology , Granulosa Cells/drug effects , Mitogen-Activated Protein Kinase 7/metabolism , Rats , Rats, Sprague-Dawley
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