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1.
Am J Epidemiol ; 2024 Jun 21.
Article in English | MEDLINE | ID: mdl-38907335

ABSTRACT

China's Clean Air Act (CCAA) has been demonstrated to reduce the public health burden of ambient air pollution. Few studies have assessed the health effects of CCAA on lung function. We aimed to investigate the effects of CCAA and PM2.5 exposures on peak expiratory flow (PEF) in middle-aged and older people in China. Three waves (2011, 2013, and 2015) of the China Health and Retirement Longitudinal Study (CHARLS) were included in this study. We performed a difference-in-difference (DID) model and mixed effect method to assess the association between CCAA, PM2.5, and PEF. To increase the reliability, multiple environmental factors were considered, and spline function was utilized to fit the spatial autocorrelations. We found that the risk of decreased PEF in the policy intervention group was reduced by 46% (95% CI: 23%~62%). The estimate showed a 10µg/m3 increase in PM2.5 would increase the risk of decreased PEF by 10% (95% CI: 3%~18%). The results of the mixed effect model showed a 10 µg/m3 increase in PM2.5 concentration was associated with a 2.23% (95% CI: 1.35%~3.06%) decrease in the PEF. These results contributed to the limited epidemiology evidence on demonstrating the effect of PM2.5 on lung function.

2.
Int J Geriatr Psychiatry ; 39(3): e6079, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38526446

ABSTRACT

OBJECTIVES: To investigate the accuracy of longitudinal trajectories of blood biomarkers for predicting future onset of AD among MCI participants as well as to demonstrate dynamic prediction of the individual conversion risk applying joint modeling. METHODS: A total of 446 participants with MCI at baseline from the Alzheimer's Disease Neuroimaging Initiative database were included. We introduced joint modeling to analyze the effects of the longitudinal blood biomarkers on the conversion risk to AD, and further to build individual-specific prediction risk model. RESULTS: During the follow-up, 345 participants remained with MCI and 101 progressed to AD, and were categorized as non-progression and progression group, respectively. Longitudinally, the positive association of the concentration dynamics of plasma p-tau181 and NfL with the conversion risk to AD from MCI was also demonstrated, with Hazard Ratio (HR) = 5.83 and HR = 4.18, respectively. When incorporating plasma p-tau181 and NfL together to predict AD progression, we observed improved performance (AUC = 0.701, Brier Score = 0.119). Two participants were chosen to exemplify the individual-specific risk prediction at different follow-up time for comparative analysis. CONCLUSIONS: Plasma p-tau181 and NfL could serve as biomarkers for the prediction of AD onset, and the individualized prediction opens up the possibility to provide clinical information at a personal level.


Subject(s)
Alzheimer Disease , Humans , Alzheimer Disease/diagnosis , Biomarkers , Databases, Factual , Neuroimaging
3.
Int J Geriatr Psychiatry ; 39(2): e6063, 2024 Feb.
Article in English | MEDLINE | ID: mdl-38400786

ABSTRACT

BACKGROUND: Several studies have explored the association between temperature and cognitive function. However, few studies have examined the effect of extreme temperature on cognitive function. In this study, we aimed to quantify the long-term effect of extreme temperature (e.g., heat waves, cold spells, and hot night excess (HNE)) on cognitive performance in middle-aged and older people in China. METHOD: We investigated 7915 aged >45 years people from the China Health and Retirement Longitudinal Study (CHARLS), surveyed in 2011 and 2015. A structured questionnaire was utilized to assess cognitive function, including four dimensions: episodic memory, attention, orientation, and visuo-construction. Hourly ambient temperature from the ERA5-Land datasets were used to calculate variables indicating extreme temperature. We performed difference-in-difference (DID) models to assess the potential causal relationship between extreme temperature and cognitive function. RESULTS: Non-linear analyses suggested that both sustained increases in temperature and excessive variability in temperature increased the risk of cognitive decline. Meanwhile, we observed the extra risk of global cognitive function decline was 2.3% (95% Confidence interval (95% CI): 0.2%, 4.4%) for heat waves (one unit increase) and 5.9% (95% CI: 0.6%, 11.6%) for HNE (one unit increase), while the association for cold spells was insignificant. Two cognitive dimensions, episodic memory and visuo-construction, were sensitive to these two heat-related factors. CONCLUSION: Extreme temperature was inversely related to cognitive performance in middle-aged and older adults, which was substantial for heat waves and HNE particularly. The effect size varied by cognitive dimensions.


Subject(s)
Cognition , Cold Temperature , Humans , Middle Aged , Aged , Temperature , Longitudinal Studies , China/epidemiology
4.
BMC Womens Health ; 24(1): 539, 2024 Sep 27.
Article in English | MEDLINE | ID: mdl-39334255

ABSTRACT

BACKGROUND: Although clinical guidelines exist for diagnosing abnormal uterine bleeding, there is a significant lack of agreement on the best management strategies for women presenting with symptom, particularly in diagnosing endometrial cancer. This study aimed to develop a preoperative risk model that utilizes demographic factors and transvaginal ultrasonography of the endometrium to assess and predict the risk of malignancy in females with endometrial cancer. METHODS: In this retrospective study, a logistic regression model was developed to predict endometrial carcinoma using data from 356 postmenopausal women with endometrial lesions and an endometrial thickness (ET) of 5 mm or more. These patients had undergone transvaginal ultrasonography prior to surgery, with findings including 247 benign and 109 malignant cases. The model's predictive performance was evaluated using receiver operating characteristic (ROC) curve analysis and compared with post-surgical pathological diagnoses. RESULTS: Our model incorporates several predictors for endometrial carcinoma, including age, history of hypertension, history of diabetes, body mass index (BMI), duration of vaginal bleeding, endometrial thickness, completeness of the endometrial line, and endometrial vascularization. It demonstrated a strong prediction with an area under the curve (AUC) of 0.905 (95% CI, 0.865-0.945). At the optimal risk threshold of 0.33, the model achieved a sensitivity of 82.18% and a specificity of 92.80%. CONCLUSIONS: The established model, which integrates ultrasound evaluations with demographic data, provides a specific and sensitive method for assessing and predicting endometrial carcinoma.


Subject(s)
Endometrial Neoplasms , Endometrium , Postmenopause , Ultrasonography , Humans , Female , Endometrial Neoplasms/diagnostic imaging , Endometrial Neoplasms/pathology , Endometrial Neoplasms/diagnosis , Middle Aged , Retrospective Studies , Aged , Ultrasonography/methods , Endometrium/diagnostic imaging , Endometrium/pathology , Uterine Hemorrhage/etiology , ROC Curve , Logistic Models , Predictive Value of Tests , Risk Factors , Body Mass Index , Risk Assessment/methods
5.
Bull Environ Contam Toxicol ; 112(4): 62, 2024 Apr 14.
Article in English | MEDLINE | ID: mdl-38615308

ABSTRACT

Acetamiprid is a novel nicotinic pesticide widely used in modern agriculture because of its low toxicity and specific biological target properties. The objective of this study was to understand the photolysis pattern of acetamiprid in the water column and elucidate its degradation products and mechanism. It was observed that acetamiprid exhibited different photolysis rates under different light source conditions in pure water, with ultraviolet > fluorescence > sunlight; furthermore, its photolysis half-life ranged from 17.3 to 28.6 h. In addition, alkaline conditions (pH 9.0) accelerated its photolysis rate, which increased with pH. Using gas chromatography-mass spectrometry, five direct photolysis products generated during the exposure of acetamiprid to pure water were successfully separated and identified. The molecular structure of acetamiprid was further analyzed using density functional theory, and the active photodegradation sites of acetamiprid were predicted. The mechanism of the photolytic transformation of acetamiprid in water was mainly related to hydroxyl substitution and oxidation. Based on these findings, a comprehensive transformation pathway for acetamiprid was proposed.


Subject(s)
Neonicotinoids , Pesticides , Nicotine , Agriculture , Water
7.
BMC Public Health ; 22(1): 569, 2022 03 22.
Article in English | MEDLINE | ID: mdl-35317761

ABSTRACT

BACKGROUND: Epidemiological evidence has shown an association between long-term exposure to fine particulate matter (PM2.5) and hypertension and diabetes, but few studies have considered the spatial properties of the samples. This study aimed to investigate the long-term effect of PM2.5 exposure on hypertension and diabetes among middle-aged and elderly people in China based on a spatial study. METHODS: We conducted a national cross-sectional study of the most recently launched wave 4 2018 data of the China Health and Retirement Longitudinal Study (CHARLS) to calculate the prevalence of hypertension and diabetes. The exposure data of annual average PM2.5 concentrations were estimated combined with satellite observations, chemical transport modeling, and ground-based monitoring. A shared component model (SCM) was used to explore the association of PM2.5 with hypertension and diabetes, in which these two diseases borrowed information on spatial variations from each other. Then, we evaluated the effect variations in PM2.5 in different periods and smoking status on changes in outcomes. RESULTS: The prevalence of hypertension and diabetes was 44.27% and 18.44%, respectively, among 19,529 participants. The annual average PM2.5 concentration in 31 provinces ranged from 4.4 µg/m3 to 51.3 µg/m3 with an average of 27.86 µg/m3 in 2018. Spatial auto-correlations of the prevalence of hypertension and diabetes and PM2.5 concentrations were seen (Moran's I = 0.336, p = 0.01; Moran's I = 0.288, p = 0.03; Moran's I = 0.490, p = 0.01). An interquartile range (IQR: 16.2 µg/m3) increase in PM2.5 concentrations was significantly associated with a higher prevalence of hypertension and diabetes with odds ratios (ORs) of 1.070 [95% credible interval (95% CrI): 1.034, 1.108] and 1.149 (95% CrI: 1.100, 1.200), respectively. Notably, the effect of PM2.5 on both hypertension and diabetes was relatively stronger among non-smokers than smokers. CONCLUSION: Our nationwide study demonstrated that long-term exposure to PM2.5 might increase the risk of hypertension and diabetes, and could provide guidance to public policymakers to prevent and control hypertension and diabetes according to the spatial distribution patterns of the above effects in China.


Subject(s)
Air Pollutants , Air Pollution , Diabetes Mellitus , Hypertension , Aged , Air Pollutants/adverse effects , Air Pollutants/analysis , Air Pollution/adverse effects , Air Pollution/analysis , China/epidemiology , Cross-Sectional Studies , Diabetes Mellitus/epidemiology , Environmental Exposure/adverse effects , Environmental Exposure/analysis , Humans , Hypertension/epidemiology , Longitudinal Studies , Middle Aged , Particulate Matter/adverse effects , Particulate Matter/analysis
8.
BMC Musculoskelet Disord ; 22(1): 536, 2021 Jun 12.
Article in English | MEDLINE | ID: mdl-34118908

ABSTRACT

BACKGROUND: Degenerative lumbar spinal stenosis (DLSS) is a common degenerative condition in older adults. Muscle atrophy (MA) is a leading cause of muscle weakness and disability commonly reported in individuals with spinal stenosis. The purpose of this study was to investigate if the MA correlates with the grade of spinal stenosis in patients with DLSS. METHODS: A retrospective analysis on 48 male and 184 female DLSS patients aged around 54.04 years (54.04 ± 8.93) were involved and divided into 6 groups according to claudication-distance-based grading of spinal stenosis, which confirmed by two independent orthopedic surgeons using T2- weighted images. Using 1.5T MRI scanner, the severity of MA is assessed based on its negative correlation with the ratio of total fat-free multifidus muscle cross-sectional area (TFCSA) to total multifidus muscle cross-sectional area (TCSA). Adobe Photoshop CS6 was used for qualitative image analysis and calculate the TFCSA/TCSA ratio to assess the severity of MA, compare the grade of MA with the spinal stenosis segment, stenosis grade and symptom side. RESULTS: In DLSS group, The TFCSA/TCSA ratio are 74.33 ± 2.18 in L3/4 stenosis, 75.51 ± 2.79 in L4/5 stenosis, and 75.49 ± 2.69 in L5/S1 stenosis. there were significant decreases in the TFCSA/TCSA ratio of stenotic segments compared with non-stenotic segments of the spinal canal (P < 0.05) while no significant difference between the non-stenotic segments (P > 0.05). TFCSA/TCSA ratios is significant differences in the TFCSA/TCSA ratios of the 6 DLSS groups (F = 67.832; P < 0.05). From Group 1 to Group 6, the TFCSA/TCSA ratio of stenotic segments positively correlated with the absolute claudication distance (ACD). (P < 0.001, r = 0.852). Besides, the TFCSA/TCSA ratios are smaller in the symptomatic sides of the spine than the contralateral sides (t = 4.128, P = 0.001). CONCLUSIONS: The stenotic segments of the spinal canal are more atrophied than the non-stenotic segment in DLSS patients. It is shows that a strong positive correlation between the severity of multifidus atrophy and the severity of spinal stenosis.


Subject(s)
Spinal Stenosis , Aged , Female , Humans , Lumbar Vertebrae/diagnostic imaging , Lumbar Vertebrae/pathology , Magnetic Resonance Imaging , Male , Muscular Atrophy/diagnostic imaging , Muscular Atrophy/etiology , Muscular Atrophy/pathology , Paraspinal Muscles/diagnostic imaging , Paraspinal Muscles/pathology , Retrospective Studies , Spinal Stenosis/complications , Spinal Stenosis/diagnostic imaging , Spinal Stenosis/pathology
9.
J Antimicrob Chemother ; 75(9): 2495-2498, 2020 09 01.
Article in English | MEDLINE | ID: mdl-32363389

ABSTRACT

OBJECTIVES: To verify the contribution of the globally disseminated Neisseria gonorrhoeae FC428 clone to the emergence of ceftriaxone resistance in Chengdu in south-west China during 2018. METHODS: Antimicrobial susceptibility of the N. gonorrhoeae isolates to six antibiotics was determined using the agar dilution method. A real-time PCR assay and WGS were used to identify the FC428 clone. Phylogenomic and molecular antimicrobial resistance analyses were conducted to characterize the transmission and evolution of related strains. RESULTS: Four out of 112 N. gonorrhoeae isolates were confirmed as the ceftriaxone-resistant FC428 clone. Phylogenomic analysis revealed that they resulted from multiple introductions and subsequent local transmissions. The strains have undergone further evolutions characterized by the accumulation of mutations in resistance-associated genes and/or the acquisition of plasmids encoding penicillin and tetracycline resistance genes. CONCLUSIONS: The N. gonorrhoeae FC428 clone has spread to south-west China. Efforts should be made to enhance gonococcal antimicrobial surveillance to control further dissemination of this successful clone at both local and national levels.


Subject(s)
Gonorrhea , Neisseria gonorrhoeae , Anti-Bacterial Agents/pharmacology , Ceftriaxone/pharmacology , China/epidemiology , Clone Cells , Genomics , Gonorrhea/epidemiology , Humans , Microbial Sensitivity Tests , Neisseria gonorrhoeae/genetics
10.
J Cell Biochem ; 119(11): 9028-9041, 2018 11.
Article in English | MEDLINE | ID: mdl-30011095

ABSTRACT

Bovine mastitis occurs frequently in dairy cows and is often caused by various aetiological organisms, for example, Escherichia coli. Lipopolysaccharide (LPS) is a key virulence factor of E. coli. In this study, we stimulated bovine mammary epithelial cells (BMECs) with LPS to investigate the global transcriptional response and identify specific proinflammatory factors that play important roles in blood-milk barrier damage during mastitis caused by E. coli. By performing RNA-seq, we identified a large number of significantly differentially expressed genes (DEGs) between the LPS-treated BMECs and the control cells. Among the DEGs, interleukin-1ß (IL-1ß) was selected because its messenger RNA expression was induced by LPS and its enrichment is involved in multiple inflammatory signal pathways, and its roles in blood-milk barrier damage during the process of mastitis were investigated. Exogenous IL-1ß treatment damaged the integrity of the blood-milk barrier, as indicated by the increased BMEC tight junction (TJ) permeability and confirmed by in vitro and in vivo experiments. Furthermore, the IL-1ß-induced increase in the BMEC TJ permeability was mediated by the IL-1ß-ERK1/2-MLCK axis pathway. Our data provide insights into the functions of IL-1ß in blood-milk barrier damage caused by mastitis in dairy cows.


Subject(s)
Epithelial Cells/drug effects , Epithelial Cells/metabolism , Interleukin-1beta/pharmacology , Mammary Glands, Animal/cytology , Mitogen-Activated Protein Kinase 1/metabolism , Mitogen-Activated Protein Kinase 3/metabolism , Tight Junctions/metabolism , Animals , Blotting, Western , Cattle , Cell Proliferation/drug effects , Claudin-1/metabolism , Female , Mice , Occludin/metabolism , Real-Time Polymerase Chain Reaction , Reverse Transcriptase Polymerase Chain Reaction , Tight Junctions/drug effects , Zonula Occludens-1 Protein/metabolism
11.
Mediators Inflamm ; 2018: 4093285, 2018.
Article in English | MEDLINE | ID: mdl-29686530

ABSTRACT

The expression of cytochrome P4501A1 (CYP1A1) enzyme is changed in various organs during the host response to inflammation or infection, leading to alterations in the metabolism of endogenous and exogenous compounds. Results of this study showed that CYP1A1 expression was significantly downregulated in the mammary tissue of bovine with mastitis, in inflammatory epithelial cells (INEs) extracted from the tissue, and in lipopolysaccharide- (LPS-) induced INEs compared with their corresponding counterparts. Overexpression of CYP1A1 in bovine mammary epithelial cells alleviated the LPS-induced inhibition of epithelial proliferation, abated the LPS-induced increase of gene expression and protein secretion of inflammatory cytokine tumor necrosis factor-α and interleukin-6, and attenuated the LPS-induced activation of NF-κB signaling. These findings suggest that CYP1A1 has immense potential in the regulation of inflammatory responses in bovine mammary epithelial cells during mastitis and may serve as a useful therapeutic target in mitigating injuries caused by inflammatory overreaction.


Subject(s)
Cytochrome P-450 CYP1A1/metabolism , Epithelial Cells/metabolism , Inflammation/chemically induced , Inflammation/metabolism , Lipopolysaccharides/toxicity , Mammary Glands, Animal/cytology , Animals , Cattle , Cell Line , Cytochrome P-450 CYP1A1/genetics , Epithelial Cells/drug effects , Female , Inflammation/immunology , Interleukin-6/metabolism , Mastitis/immunology , Mastitis/metabolism , Real-Time Polymerase Chain Reaction , Signal Transduction/drug effects , Tumor Necrosis Factor-alpha/metabolism
12.
Cell Physiol Biochem ; 43(1): 82-93, 2017.
Article in English | MEDLINE | ID: mdl-28848180

ABSTRACT

BACKGROUND/AIMS: Transforming growth factor-ß1 (TGF-ß1) plays a crucial role in chronic inflammation in various tissues, and is related to inflammation-caused organ fibrogenesis associated with the epithelial-mesenchymal transition (EMT) and the deposition of the extracellular matrix (ECM). However, the effect of TGF-ß1 on bovine mammary epithelial cells (BMECs) with mastitis, and its mechanism, remain unknown. METHODS: We analyzed the level of TGF-ß1 in inflamed mammary tissues and cells using western blotting. BMECs were treated with TGF-ß1, and EMT-related gene and protein expression changes were evaluated using quantitative real-time polymerase chain reaction (qPCR), western blotting, and immunofluorescence. We also inhibited the TGF/Smad signaling pathway using a receptor inhibitor, and analyzed EMT-related protein expression by western blotting. In addition, we injected TGF-ß1 into mice mammary glands to investigate whether it can cause mammary fibrosis in vivo. RESULTS: The TGF-ß1 level was up-regulated in mammary tissues with mastitis and in inducible inflammatory BMECs. TGF-ß1 treatment activated the TGF/ Smad signaling pathway in BMECs during their transition to the EMT phenotype, as indicated by morphological changes from a cobblestone-like shape to a spindle-like one. TGF-ß1 treatment also up-regulated the expression of α-smooth muscle actin, vimentin, and collagen I, albumin, and down-regulated the expression of E-cadherin both in mRNA level and protein level. Furthermore, TGF-ß1 enhanced the gene expressions of MMP2, MMP7, and fibronectin in BMECs. TGF-ß1 injection induced mice mammary infection and fibrosis. CONCLUSION: These findings suggested that aberrant up-regulation of TGF-ß1 in bovine mastitic mammary glands might play an important role in bovine mammary fibrosis caused by unresolved inflammation.


Subject(s)
Epithelial-Mesenchymal Transition/drug effects , Signal Transduction/drug effects , Smad Proteins/metabolism , Transforming Growth Factor beta1/pharmacology , Actins/metabolism , Animals , Cadherins/metabolism , Cattle , Cells, Cultured , Epithelial Cells/cytology , Epithelial Cells/drug effects , Epithelial Cells/metabolism , Female , Mammary Glands, Animal/cytology , Matrix Metalloproteinase 2/genetics , Matrix Metalloproteinase 2/metabolism , Matrix Metalloproteinase 7/genetics , Matrix Metalloproteinase 7/metabolism , Mice , Phosphorylation/drug effects , Pyrazoles/pharmacology , Pyrroles/pharmacology , RNA, Messenger/metabolism , Real-Time Polymerase Chain Reaction , Transforming Growth Factor beta1/genetics , Transforming Growth Factor beta1/metabolism , Up-Regulation/drug effects
13.
Biochem Biophys Res Commun ; 491(3): 807-813, 2017 09 23.
Article in English | MEDLINE | ID: mdl-28669729

ABSTRACT

Oxidative stress has currently been proposed as a risk factor associated with the development and proression of osteoporosis. In this study, we identify the effect of mangiferin (MAN) on apoptosis and differentiation of osteoblast-like MC3T3-E1 cells insulted by H2O2. We firstly found that MAN can promote cell proliferation of MC3T3-E1 cells in a time- and dose-dependent manner and stimulate the phosphorylation of ERK5. Cells were divided as five groups: control, H2O2 (100 µM, control), H2O2 + MAN (5 µM), H2O2 + MAN (10 µM), and H2O2 + MAN (20 µM). MAN can significantly decrease H2O2-induced apoptosis and elevated ROS level of MC3T3-E1 cells. The expressions of caspase-3, caspase-9 and Bax/Bcl-2 were increased with H2O2 treatment, and MAN can reverse these changes. In addition, Nrf2 and its downstream target effectors (HO1, NQO1) were dramatically attenuated in MC3T3-E cells treatment with H2O2, while MAN can significantly increase the expression of Nrf2, HO1 and NQO1. The expression of ERK5 was down regulated by RNA interference in MC3T3-E1 cells, and we found that MAN (20 µM) pretreatment didn't make remarkable decrease in cell apoptosis or expressions of apoptosis-related proteins in H2O2-insulted siRNA-ERK5 cells. This study indicated that MAN can protect osteoblast against oxidative damage by modulation of ERK5/Nrf2 signaling, which can be new agent for osteoporosis.


Subject(s)
Apoptosis/physiology , Hydrogen Peroxide/administration & dosage , Osteoblasts/physiology , Oxidative Stress/drug effects , Oxidative Stress/physiology , Xanthones/administration & dosage , Animals , Apoptosis/drug effects , Dose-Response Relationship, Drug , Drug Interactions , Mice , NIH 3T3 Cells , Osteoblasts/cytology , Osteoblasts/drug effects , Signal Transduction/drug effects , Signal Transduction/physiology
14.
Tumour Biol ; 39(2): 1010428317690999, 2017 Feb.
Article in English | MEDLINE | ID: mdl-28231734

ABSTRACT

Abnormal expression of long non-coding RNA often contributes to unrestricted growth of cancer cells. Long non-coding RNA XIST expression is upregulated in several cancers; however, its modulatory mechanisms have not been reported in hepatocellular carcinoma. In this study, we found that XIST expression was significantly increased in hepatocellular carcinoma tissues and cell lines. XIST promoted cell cycle progression from the G1 phase to the S phase and protected cells from apoptosis, which contributed to hepatocellular carcinoma cell growth. In addition, we revealed that there was reciprocal repression between XIST and miR-139-5p. PDK1 was identified as a direct target of miR-139-5p. We proposed that XIST was responsible for hepatocellular carcinoma cell proliferation, and XIST exerted its function through the miR-139-5p/PDK1 axis.


Subject(s)
Carcinoma, Hepatocellular/pathology , Liver Neoplasms/pathology , MicroRNAs/metabolism , Protein Serine-Threonine Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , RNA, Long Noncoding/biosynthesis , Animals , Carcinoma, Hepatocellular/genetics , Carcinoma, Hepatocellular/metabolism , Case-Control Studies , Cell Line, Tumor , Hep G2 Cells , Humans , Liver Neoplasms/genetics , Liver Neoplasms/metabolism , Male , Mice , Mice, Inbred BALB C , MicroRNAs/genetics , Protein Serine-Threonine Kinases/genetics , Proto-Oncogene Proteins c-akt/genetics , Pyruvate Dehydrogenase Acetyl-Transferring Kinase , RNA, Long Noncoding/genetics , RNA, Long Noncoding/metabolism
15.
Wei Sheng Wu Xue Bao ; 56(11): 1755-65, 2016 Nov 04.
Article in Zh | MEDLINE | ID: mdl-29741839

ABSTRACT

Objective: Streptococcus equi subsp. zooepidemicus (GCS) is mainly used to produce hyaluronic acid (HA) in the industry. GCS secretes the hemolysis toxin (streptolysin S, SLS) that causes hemolysis in the host cells. Therefore, the safety of HA produced by GCS is concerned. We constructed an engineering strain, to produce commercial HA without SLS by knocking out saga. Method: The sagA of GCS was knocked out by the thermosensitive delivery vector system pJR700. The sagA mutant was identified through PCR with primers homologous to the flanking regions and SLS analysis. The yield of HA, HA molecular weight and virulence factors such as streptolysin Hylc, hyaluronate lyase, glyceraldehyde-3-phosphate dehydrogenase and cell surface proteins were determined by spectrophotometer and SDS-PAGE. Result: We constructed successfully the in-frame deletion sagA mutant strain of GCS. In the sagA mutant, HA titer increased more than 30% than that of the wild type strain and no SLS hemolytic activity was detected. Compared to the wild type strain the sagA mutant decreased the quality of surface proteins, hemolytic Hylc activity and glyceraldehyde-3-phosphate dehydrogenase activity. The activities of hyaluronidase and cell were increased in the sagA mutant. Conclusion: The sagA not only expressed hemolysis S but also regulated production of HA, the quality of surface proteins and activities of hyaluronidase, hemolysis Hylc and glyceraldehydes-3-phosphate dehydrogenase in Streptococcus equi subsp. zooepidemicus.


Subject(s)
Bacterial Proteins/genetics , Hemolysin Proteins/genetics , Hyaluronic Acid/biosynthesis , Streptococcus equi/genetics , Streptococcus equi/metabolism , Bacterial Proteins/metabolism , Hemolysin Proteins/metabolism , Mutation , Polysaccharide-Lyases/genetics , Polysaccharide-Lyases/metabolism , Streptolysins/biosynthesis
16.
J Cell Biochem ; 116(6): 1080-9, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25640278

ABSTRACT

Bone morphogenetic proteins (BMPs) are members of the TGF-ß superfamily signaling factors. Expression of several BMPs (BMP2, BMP4, and BMP7) is correlated to poor prognosis in gastric cancer patients. The function of BMP9, the latest discovered and most powerful osteogenetic factor, in gastric cancer is relatively unclear. In this report, we investigated the expression, function and underlying molecular mechanisms of BMP9 in gastric cancer. The results show that BMP9 expression was markedly decreased in gastric cancer tissues and cell lines. Enforced BMP9 expression in the gastric cancer cell lines SGC-7901 and MNK-45 increased apoptosis and reduced viability and migration. The in vivo function of BMP9 was evaluated in a xenograft mouse model. Tumors derived from SGC-7901 cells with enforced BMP9 expression (SGC-7901/BMP9) showed significantly reduced size and weight compared to that from control cells. Enforced BMP9 expression resulted in decreased Akt activity shown as lower levels of phosphorylation at Ser473 and Thr308 in Akt. The PI3K/Akt inhibitor LY294002 potentiated BMP9's viability and migration suppression, and apoptosis induction, which was associated with reduced expression of snail and VEGF and increased expression of E-cadherin. In addition, tumors derived from SGC-7901/BMP9 showed reduced Akt activity and VEGF expression, and increased E-cadherin expression. Therefore, our studies reveal for the first time that inhibition of the PI3K-Akt pathway is involved in the tumor suppressor effects of BMP9 in gastric cancer.


Subject(s)
Growth Differentiation Factor 2/metabolism , Phosphatidylinositol 3-Kinase/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Stomach Neoplasms/metabolism , Apoptosis/drug effects , Apoptosis/genetics , Cadherins/genetics , Cadherins/metabolism , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Proliferation/genetics , Cell Survival/drug effects , Cell Survival/genetics , Chromones/pharmacology , Growth Differentiation Factor 2/genetics , Humans , Morpholines/pharmacology , Phosphoinositide-3 Kinase Inhibitors , Proto-Oncogene Proteins c-akt/antagonists & inhibitors , Signal Transduction/drug effects , Signal Transduction/genetics , Stomach Neoplasms/genetics
18.
J Microencapsul ; 32(1): 46-53, 2015.
Article in English | MEDLINE | ID: mdl-25090591

ABSTRACT

In this study, peptidoglycan microspheres were evaluated for their toxicity and adjuvant effects after oral administration to mice. The liver and spleen indexes, CD cell content in peripheral blood and spleen, and immunoglobulin content in peripheral blood were measured by flow cytometry and indirect ELISA, respectively. Peptidoglycan microspheres with a loading capacity of 46.41 ± 0.83 g/100 g were prepared. In vivo tests showed that peptidoglycan microspheres revealed an immuno-enhancing profile as indicated by the slow increase of IgG content in peripheral blood compared with that of the untreated peptidoglycan group. In conclusion, peptidoglycan microspheres may be used as a new oral adjuvant in the host.


Subject(s)
Adjuvants, Immunologic , Microspheres , Peptidoglycan , Adjuvants, Immunologic/pharmacokinetics , Adjuvants, Immunologic/pharmacology , Administration, Oral , Animals , Drug Evaluation, Preclinical , Immunoglobulin G/blood , Immunoglobulin G/immunology , Mice , Peptidoglycan/immunology , Peptidoglycan/pharmacology
19.
Nanotechnology ; 25(12): 125301, 2014 Mar 28.
Article in English | MEDLINE | ID: mdl-24571933

ABSTRACT

This paper presents a novel ultraviolet (UV)-driven microvalve based on the concept of inserting a trimethyl chlorosilane (CTMS) modified TiO2/SiO2 composite patch of switchable wettability in a microfluidic system. A unique micro-nano hierarchical structure was designed and used to enhance the overall wetting contrast with the aim of improving the wetting-based valve performances. Field-emission scanning electron microscopy (FE-SEM) and x-ray photoelectron spectroscopy (XPS) were used to characterize the morphology and chemical composition of the surface. UV-driven wettability conversion on the patched microchannel was investigated using water column relative height tests, and the results confirmed the significant improvement of the hierarchical structure with the surface hydrophobic/hydrophilic conversion, which produced enhancements of 276% and 95% of the water-repellent and water-sucking pressures, respectively, compared with those of the single-scale TiO2 nanopatterned structure. Accordingly, a good reversible and repeated on-off performance was identified by the valve tests, highlighting the potential application of the novel microvalve in the efficient control of microscale flow.

20.
Int J Med Sci ; 11(8): 841-9, 2014.
Article in English | MEDLINE | ID: mdl-24936148

ABSTRACT

The S100 protein family member S100A4 regulates various cellular functions. Previous studies have shown that elevated expression of S100A4 is associated with progression and metastasis of colorectal cancer (CRC). However, little is known about whether and how S100A4 contributes to CRC development. In our present study, the elevated expression of S100A4 in CRC tissues compared to matched adjacent normal tissues was confirmed by immunohistochemistry, semi-quantitative RT-PCR and Western blot. Adenovirus-mediated S100A4 overexpression obviously enhanced viability and migration of CRC cells, which was detected by MTT assay and transwell assay, respectively. Additionally, S100A4 overexpression increased the phosphorylation levels of Akt, mTOR and p70S6K. These effects of S100A4 were abolished by treatment with either the specific PI3K/Akt inhibitor LY294002, or the specific mTOR/p70S6K inhibitor rapamycin. Furthermore, overexpression of S100A4 resulted in upregulation of VEGF and downregulation of E-cadherin, which were strongly reversed by either LY294002 or rapamycin. Altogether, our results demonstrate that activation of the PI3K/Akt/mTOR/p70S6K signaling pathway is involved in S100A4-induced viability, migration, upregulation of VEGF and downregulation of E-cadherin in CRC cells.


Subject(s)
Colorectal Neoplasms/genetics , Phosphatidylinositol 3-Kinases/genetics , Proto-Oncogene Proteins c-akt/genetics , Ribosomal Protein S6 Kinases, 70-kDa/genetics , S100 Proteins/biosynthesis , TOR Serine-Threonine Kinases/genetics , Cadherins/biosynthesis , Cell Line, Tumor , Cell Movement/genetics , Colorectal Neoplasms/pathology , Enzyme Inhibitors/administration & dosage , Gene Expression Regulation, Neoplastic/drug effects , Gene Expression Regulation, Neoplastic/genetics , Humans , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Ribosomal Protein S6 Kinases, 70-kDa/metabolism , S100 Calcium-Binding Protein A4 , S100 Proteins/genetics , Signal Transduction/genetics , TOR Serine-Threonine Kinases/metabolism , Vascular Endothelial Growth Factor A/biosynthesis
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