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1.
Medicine (Baltimore) ; 99(2): e18499, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31914019

RESUMO

BACKGROUND: Previous studies have reported the association between Mycoplasma fermentans (M. fermentans) and the risk of human immunodeficiency virus 1 (HIV-1) infection, but the results were inconsistent. The present study aims to systematically review reported studies on M. fermentans and its association with HIV-1 infection, as well as to summarize the findings using a meta-analysis. METHODS: Studies meeting the inclusion criteria in the PubMed, Embase, China National Knowledge Infrastructure, WanFang Data, and Chongqing VIP databases up to March 2019 were identified. Cochran Q and I statistics were used to assess heterogeneity. Additionally, pooled odds ratio (OR) with 95% confidence intervals (CI) were calculated and displayed by Forest plots. Also, the funnel plot, Begg test, and Egger test were used to evaluate potential publication bias. In addition, the source of heterogeneity was investigated by subgroup and sensitivity analyses. RESULTS: A total of 11 studies comprising 1028 HIV-1-positive patients and 1298 controls were ultimately included in this meta-analysis. Our results indicated that M. fermentans could increase the risk of HIV-1 infection among humans (OR = 3.66, 95%CI 1.26-10.64). Subgroup analysis showed that the risk of HIV-1 infection associated with M. fermentans was, based on the geographical distribution, 1.19 (95%CI 0.33-4.33) in Europe, 2.83 (95%CI 0.94-8.52) in United States, 11.92 (95%CI 3.93-36.15) in Asia; based on the source of the sample, 2.97 (95%CI 0.89-9.95) in blood samples, 4.36 (95%CI 1.63-11.68) in urine samples; based on the detection method, 2.80 (95%CI 0.72-10.96) with the polymerase chain reaction method, 5.54 (95%CI 1.21-25.28) with other detection methods; based on the source of controls, 1.91 (95%CI 0.53-6.89) in sexually transmitted diseases individuals, and 8.25 (95%CI 2.16-31.60) in health individuals. CONCLUSION: Our study revealed evidence of the association between M. fermentans and HIV-1 infection. Considering the heterogeneity, further studies are warranted to understand the relationship between M. fermentans and HIV-1 infection.


Assuntos
Infecções por HIV/etiologia , Soropositividade para HIV/diagnóstico , Infecções por Mycoplasma/complicações , Mycoplasma fermentans/metabolismo , Ásia/epidemiologia , Europa (Continente)/epidemiologia , Feminino , Infecções por HIV/diagnóstico , Soropositividade para HIV/complicações , Soropositividade para HIV/virologia , HIV-1/genética , HIV-1/isolamento & purificação , Humanos , Masculino , Infecções por Mycoplasma/microbiologia , Mycoplasma fermentans/isolamento & purificação , Fatores de Risco , Estados Unidos/epidemiologia
2.
Chem Res Toxicol ; 33(1): 202-210, 2020 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-31777246

RESUMO

As one of the primary contributors to high clinical attrition rates of drugs, toxicity evaluation is of critical significance to new drug discovery. Unsurprisingly, a vast number of computational methods have been developed at various stages of development pipeline to evaluate potential adverse drug reactions (ADRs). Despite previous success of these methods on individual ADR or certain drug family, there are great challenges to toxicity evaluation. In this study, a novel strategy was developed to predict the drug-ADR associations by combining deep learning and the biomedical tripartite network. This heterogeneous network contains biomedical linked data of three entities, for example, drugs, targets, and ADRs. For the first time, GraRep, a deep learning method for distributed representations, is introduced to learn graph representations and identify hidden features from the tripartite network which are further used for ADR prediction. Through this approach, drug-ADR associations could possibly be discovered from a systemic perspective. The accuracy of our method is 0.95 based on internal resource validation and 0.88 based on external resource validation. Moreover, our results show the prediction accuracy using the tripartite network is better than the one with bipartite network, suggesting the model performance can be improved with further enrichment on information. According to the result of 10-fold cross validation, the deep learning model outperforms two traditional methods (topology-based measures and chemical structure-based measures). Additionally, predictive models are also constructed using other deep learning methods, and comparable results are achieved. In summary, the biomedical tripartite network-based deep learning model proposed here proves to offer a promising solution for prediction of ADRs.

3.
Comput Biol Med ; 116: 103531, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31739005

RESUMO

Abdominal hernia is a common disease, and the most effective treatment of it is using surgical meshes. However, it was found that due to the mismatch of the mechanical properties between the mesh and the tissues around the hernia, there was still a recurrence rate of more than 33% and a high probability of postoperative discomfort. Currently, because of the complex mechanical environment provided by the abdominal tissues and the lack of quantitative research, it is still difficult to select a mesh with suitable mechanical properties for a hernia with specific position and size. Therefore, the purpose of this study is to use numerical models to evaluate the mechanical behavior of both abdominal wall and meshes after repair, and to determine the most suitable mechanical properties of meshes for specific hernias, including elastic modulus and tensile strength. To realize that purpose, defects with different locations and sizes were considered, including defects of 20 mm and 40 mm in diameter on linea alba (LA20 and LA40) and on rectus abdominis (RA20 and RA40), and laparoscopic repair was simulated. The mechanical properties of the most suitable mesh we determined are as follows: suitable modulus for LA20, LA40, RA20 and RA40 are 1 MPa, 3 MPa, 2 MPa and 4 MPa, respectively; suitable tensile strength for LA20, LA40, RA20 and RA40 are 0.35 MPa, 0.89 MPa, 0.77 MPa and 1.43 MPa, respectively. These data could give a standard of mechanical properties which can be referenced in mesh design and evaluation and provide surgeons with treatment advice for specific patients.

4.
Huan Jing Ke Xue ; 40(6): 2821-2826, 2019 Jun 08.
Artigo em Chinês | MEDLINE | ID: mdl-31854676

RESUMO

This research investigated the performance of an aerobic granular reactor treating biogas slurry from pig farm. Results indicated that the granular structure of aerobic sludge was not affected by the high pollution concentrationsin the biogas slurry. Although a low removal rate of phosphate was found in this study (about 16%±2%), organic matter and ammonia nitrogen showed stable removal and transformation in the granular system, and the effluent concentrations of those components were (267±81)mg·L-1 and(62±12)mg·L-1, respectively. In addition, the removal rate of sulfamethazine and tetracycline was 98%±2% and 65%±16%, respectively. During the process biogas slurry treatment, bacterial communities in the aerobic granular reactor remained stable, and Comamonadaceae was the dominant bacteria (relative abundance ofapproximately 16.66%).

5.
BMC Med Genet ; 20(1): 175, 2019 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-31706287

RESUMO

BACKGROUND: Cancer is a heterogeneous disease with many genetic variations. Lines of evidence have shown copy number variations (CNVs) of certain genes are involved in development and progression of many cancers through the alterations of their gene expression levels on individual or several cancer types. However, it is not quite clear whether the correlation will be a general phenomenon across multiple cancer types. METHODS: In this study we applied a bioinformatics approach integrating CNV and differential gene expression mathematically across 1025 cell lines and 9159 patient samples to detect their potential relationship. RESULTS: Our results showed there is a close correlation between CNV and differential gene expression and the copy number displayed a positive linear influence on gene expression for the majority of genes, indicating that genetic variation generated a direct effect on gene transcriptional level. Another independent dataset is utilized to revalidate the relationship between copy number and expression level. Further analysis show genes with general positive linear influence on gene expression are clustered in certain disease-related pathways, which suggests the involvement of CNV in pathophysiology of diseases. CONCLUSIONS: This study shows the close correlation between CNV and differential gene expression revealing the qualitative relationship between genetic variation and its downstream effect, especially for oncogenes and tumor suppressor genes. It is of a critical importance to elucidate the relationship between copy number variation and gene expression for prevention, diagnosis and treatment of cancer.

6.
Am J Transl Res ; 11(10): 6403-6412, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31737192

RESUMO

LncRNAs are played crucial roles in athogenesis of NSCLC. LOXL1-AS1 involved in development of several tumors. So far, there is no study about expression and function pattern of the LOXL1-AS1 in NSCLC. In this reference, we firstly proved that LOXL1-AS1 was overexpressed in NSCLC cell lines (H23, A549, H1299 and SPC-A1) compared to 16HBE cell. The expression of LOXL1-AS1 was overexpressed in NSCLC specimens than adjacent control specimens. We found that 29 of 40 cases showed higher LOXL1-AS1 expression in NSCLC samples as compared to adjacent control specimens. Ectopic expression of LOXL1-AS1 promoted H1299 cell and H23 cell proliferation. LOXL1-AS1 overexpression promoted ki-67 and cyclin D1 expression in the NSCLC cell. Overexpression of LOXL1-AS1 promoted cell invasion and induced N-cadherin and Vimentin expression and suppressed E-cadherin expression in the NSCLC cell. LOXL1-AS1 acts as one sponge for miR-324-3p in NSCLC cell. Moreover, the expression of miR-324-3p was lower in NSCLC specimens than adjacent control specimens. We found that 24 of 40 cases showed lower miR-324-3p expression in NSCLC samples as compared to adjacent control specimens. Further correlation assay indicated a negative association between miR-324-3p and LOXL1-AS1 expression. miR-324-3p restoration attenuates the function of LOXL1-AS1 overexpression on NSCLC cell. These results indicated that LOXL1-AS1 enhanced NSCLC cell proliferation and invasion via sponging miR-324-3p in NSCLC cell.

7.
Front Pharmacol ; 10: 1150, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31636563

RESUMO

Ca2+ entry via the transient receptor potential vanilloid 4 (TRPV4) channel contributes to Ca2+ overload and triggers many pathophysiological conditions, including myocardial ischemia/reperfusion (I/R) injury. Propofol, a widely used intravenous anesthetic, attenuates myocardial I/R injury. However, the mechanism of propofol remains to be examined. The present study aims to test the hypothesis that propofol attenuates myocardial I/R injury through the suppression of TRPV4. We used a murine ex vivo model of myocardial I/R and in vitro cultured myocytes subjected to hypoxia/reoxygenation (H/R). Propofol or TRPV4 antagonist, HC-067047, attenuates myocardial I/R injury in isolated hearts. In addition, propofol, HC-067047, or TRPV4-siRNA attenuates H/R-induced intracellular Ca2+ concentration ([Ca2+]i) increase and cell viability reduction. On the contrary, TRPV4 agonist GSK1016790A exacerbates both ex vivo and in vitro myocardial injury. Pretreatment with propofol reverses the myocardial injury and intracellular Ca2+ overload induced by GSK1016790A at least in vitro. However, neither the combination of propofol and HC-067047 nor applying propofol to cells transfected with TRPV4-siRNA creates additional protective effects. In addition, propofol dose-dependently inhibits TRPV4-mediated Ca2+ entry induced by GSK1016790A and 4α-PDD. Propofol attenuates myocardial I/R injury partially through the suppression of TRPV4 channel and the subsequent inhibition of intracellular Ca2+ overload.

8.
Mol Carcinog ; 58(11): 2052-2064, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31397499

RESUMO

Recent studies have indicated that using statins to inhibit the mevalonate pathway induces mutant p53 degradation by impairing the interaction of mutant p53 with DnaJ subfamily A member 1 (DNAJA1). However, the role of the C-terminus of DNAJA1 with a CAAX box for farnesylation in the binding, folding, and translocation of client proteins such as mutant p53 is not known. In the present study, we used a genetically engineered mouse model of pancreatic carcinoma and showed that atorvastatin significantly increased animal survival and inhibited pancreatic carcinogenesis. There was a dramatic decrease in mutant p53 protein accumulation in the pancreatic acini, pancreas intraepithelial neoplasia lesions, and adenocarcinoma. Supplementation with farnesyl pyrophosphate, a substrate for protein farnesylation, rescued atorvastatin-induced mutant p53 degradation in pancreatic cancer cells. Tipifarnib, a farnesyltransferase inhibitor, mirrored atorvastatin's effects on mutant p53, degraded mutant p53 in a dose-dependent manner, and converted farnesylated DNAJA1 into unfarnesylated DNAJA1. Farnesyltransferase gene knockdown also significantly promoted mutant p53 degradation. Coimmunoprecipitation either by an anti-DNAJA1 or p53 antibody confirmed the direct interaction of mutant p53 and DNAJA1 and higher doses of atorvastatin treatments converted more farnesylated DNAJA1 into unfarnesylated DNAJA1 with much less mutant p53 pulled down by DNAJA1. Strikingly, C394S mutant DNAJA1, in which the cysteine of the CAAX box was mutated to serine, was no longer able to be farnesylated and lost the ability to maintain mutant p53 stabilization. Our results show that farnesylated DNAJA1 is a crucial chaperone in maintaining mutant p53 stabilization and targeting farnesylated DNAJA1 by atorvastatin will be critical for inhibiting p53 mutant cancer.


Assuntos
Atorvastatina/farmacologia , Proteínas de Choque Térmico HSP40/genética , Neoplasias Pancreáticas/tratamento farmacológico , Proteína Supressora de Tumor p53/genética , Animais , Carcinogênese/efeitos dos fármacos , Linhagem Celular Tumoral , Modelos Animais de Doenças , Farnesiltranstransferase/antagonistas & inibidores , Farnesiltranstransferase/genética , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Camundongos , Chaperonas Moleculares/genética , Proteínas Mutantes/genética , Pâncreas/metabolismo , Pâncreas/patologia , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/patologia , Prenilação/efeitos dos fármacos , Proteínas Proto-Oncogênicas p21(ras)/genética , Quinolonas/farmacologia
9.
Front Pharmacol ; 10: 731, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31293429

RESUMO

Polyunsaturated fatty acids (PUFAs) including epoxide-modified ω-3 and ω-6 fatty acids are made via oxidation to create highly polarized carbon-oxygen bonds crucial to their function as signaling molecules. A critical PUFA, arachidonic acid (ARA), is metabolized to a diverse set of lipids signaling molecules through cyclooxygenase (COX), lipoxygenase (LOX), cytochrome P450 epoxygenase, or cytochrome P450 hydroxylase; however, the majority of ARA is metabolized into anti-inflammatory epoxides via cytochrome P450 enzymes. These short-lived epoxide lipids are rapidly metabolized or inactivated by the soluble epoxide hydrolase (sEH) into diol-containing products. sEH inhibition or knockout has been a practical approach to study the biology of the epoxide lipids, and has been shown to effectively treat inflammatory conditions in the preclinical models including gastrointestinal ulcers and colitis by shifting oxylipins to epoxide profiles, inhibiting inflammatory cell infiltration and activation, and enhancing epithelial cell defense via increased mucin production, thus providing further evidence for the role of sEH as a pro-inflammatory protein. Non-steroidal anti-inflammatory drugs (NSAIDs) with COX-inhibitor activity are among the most commonly used analgesics and have demonstrated applications in the management of cardiovascular disease and intriguingly cancer. Major side effects of NSAIDs however are gastrointestinal ulcers which frequently precludes their long-term application. In this review, we hope to bridge the gap between NSAID toxicity and sEH-mediated metabolic pathways to focus on the role of epoxy fatty acid metabolic pathway of PUFAs in NSAIDS-ulcer formation and healing as well as inflammation-related carcinogenesis. Specifically we address the potential application of sEH inhibition to enhance ulcer healing at the site of inflammation via their activity on altered lipid signaling, mitochondrial function, and diminished reactive oxygen species, and further discuss the significance of dual COX and sEH inhibitor in anti-inflammation and carcinogenesis.

10.
J Phys Chem B ; 123(28): 6049-6055, 2019 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-31267745

RESUMO

The spliceosome catalyzes nuclear pre-mRNA splicing via formation of an intron lariat and is arguably the most complex macromolecular machine in eukaryotic cells. Intron lariat formation is a conservative feature of the splicing reaction for both spliceosomal and group II introns. Despite the importance of the lariat formation in pre-mRNA splicing, an atomic-level understanding of the reaction mechanism remains elusive. In this work, a quantum mechanics and molecular mechanics method with thermodynamic integration is used to calculate the free-energy profile along the reaction pathway. The results demonstrate that the catalytic Mg2+ ion does not act as a Lewis acid to activate the nucleophile and the intron lariat is formed via a dissociative transition state stabilized by electrostatic interactions with two catalytic Mg2+ ions. Proton transfer occurs from the nucleophile to the leaving oxygen group through the phosphate substrate after the transition state is reached, which is important for stabilization of the intron-lariat product and the efficiency of pre-mRNA splicing. The two-metal-ion mechanism proposed in this study provides a novel insight into understanding of the splicing reaction catalyzed by the spliceosome.

11.
Anticancer Res ; 39(7): 3651-3660, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31262891

RESUMO

BACKGROUND/AIM: Cytochrome P450 epoxygenase is a major enzyme involved in the metabolism of ω-3 polyunsaturated fatty acids (PUFAs) to produce biologically active ω-3 epoxy fatty acids (ω-3 epoxides). In general, all epoxy PUFAs including ω-3 epoxides are quickly metabolized/inactivated by soluble epoxide hydrolase (sEH) to form diol products. The aims of this study were to determine the effect and mechanism of fat-1 transgene, and ω-3 PUFA combined with sEH gene knockout or inhibitor on inhibiting pancreatic cancer and the related mechanisms involved. MATERIALS AND METHODS: PK03-mutant KrasG12D murine pancreatic carcinoma cells were inoculated into mouse models including fat-1, sEH-/- and C57BL/6J mice. The mice were fed with AIN-76A diet with or without ω-3 PUFA supplementation or treated with sEH inhibitor. In addition to tumor growth (tumor size and weight), cell proliferation, mutant Kras-mediated signaling, inflammatory reaction and angiogenesis were analyzed immunohisto-chemically and by western blot assay. ω-3 PUFA metabolism, particularly focusing on ω-3 epoxy fatty acids (ω-3 epoxides), was measured using a liquid chromatography with tandem mass spectrometry (LC-MS/MS) approach. RESULTS: Significant decreases of weight and size of the PK03 pancreatic carcinoma were observed in the fat-1 transgenic mice treated with sEH inhibitor compared to those of C57BL/6J control mice fed with AIN-76A diet (weight: 0.28±0.04 g vs. 0.58±0.06 g; size: 187.0±17.5 mm3 vs. 519.3±60.6 mm3). In a separate experiment, sEH-/- mice fed ω-3 PUFA supplement and C57BL/6J mice treated with sEH inhibitor and fed ω-3 PUFA supplement exhibited a significant reduction in the weight and size of the pancreatic carcinoma compared to C57BL/6J control mice (weight: 0.26±.26 g and 0.39±.39 g vs. 0.69±0.11 g, respectively; size: 274.2±36.2 mm3 and 296.4±99.8 mm3 vs. 612.6±117.8 mm3, respectively). Moreover, compared to the pancreatic tumors in C57BL/6J control mice, the tumors in fat-1 transgenic mice treated with sEH inhibitor showed a significant less inflammatory cell infiltrate (62.6±9.2/HPF (high power field) vs. 8.0±1.2/HPF), tumor cell proliferation (48.5±1.7% vs. 16.5±1.6%), and angiogenesis (micro-vessel density (MVD): 35.0±1.0 vs. 11.1±0.5) immunohistochemically, as well as significantly increased caspase-3 labeled apoptosis (0.44±0.06% vs. 0.69±0.06%, respectively). Using western blot approach, significant inhibition of mutant Kras-activated signals including phosphorylated Serine/threonine kinases (cRAF), Mitogen-activated protein kinase kinase (MEK), and extracellular signal-regulated kinase (ERK) were identified in pancreatic carcinoma of fat-1 transgenic mice treated with sEH inhibitor. Eicosanoic acid metabolic profiling of the serum specimens detected a significant increase of the ratios of epoxides to dihydroxy fatty acid (DiHDPE) for docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA), and epoxides/dihydroxy octadecenoic acid (DiHOME) for arachidonic acid (ARA) and linoleic acid (LA), as well as a significant increase of epoxy metabolites of DHA, EPA, ARA and LA in fat-1 transgenic mice treated with a sEH inhibitor. CONCLUSION: ω-3 epoxy products from ω-3 PUFA metabolism play a crucial role in inhibiting pancreatic cancer growth, and use of ω-3 PUFAs combined with sEH inhibition is a strategy with high potential for pancreatic cancer treatment and prevention.


Assuntos
Adenocarcinoma/terapia , Proteínas de Caenorhabditis elegans/genética , Suplementos Nutricionais , Compostos de Epóxi/farmacologia , Ácidos Graxos Dessaturases/genética , Ácidos Graxos Ômega-3/farmacologia , Neoplasias Pancreáticas/terapia , Adenocarcinoma/patologia , Animais , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neoplasias Pancreáticas/patologia
12.
Oxid Med Cell Longev ; 2019: 7283683, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31308876

RESUMO

Antioxidative stress provides a cardioprotective effect during myocardial ischemia/reperfusion (I/R). Previous research has demonstrated that the blockade of transient receptor potential vanilloid 4 (TRPV4) attenuates myocardial I/R injury. However, the underlying mechanism remains unclear. The current study is aimed at investigating the antioxidative activity of TRPV4 inhibition and elucidating the underlying mechanisms in vitro and ex vivo. We found that the inhibiting TRPV4 by the selective TRPV4 blocker HC-067047 or specific TRPV4-siRNA significantly reduces reactive oxygen species (ROS) and methane dicarboxylic aldehyde (MDA) levels in H9C2 cells exposed to hypoxia/reoxygenation (H/R). Meanwhile, the activity of antioxidative enzymes, particularly superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), is enhanced. Furthermore, after H/R, HC-067047 treatment increases the expression of P-Akt and the translocation of nuclear factor E2-related factor 2 (Nrf2) and related antioxidant response element (ARE) mainly including SOD, GSH-Px, and catalase (CAT). LY294002, an Akt inhibitor, suppresses HC-067047 and specific TRPV4-siRNA-induced Nrf2 expression and its nuclear accumulation. Nrf2 siRNA attenuates HC-067047 and specific TRPV4-siRNA-induced ARE expression. In addition, treatment with LY294002 or Nrf2 siRNA significantly attenuates the antioxidant and anti-injury effects of HC-067047 in vitro. Finally, in experiments on isolated rat hearts, we confirmed the antioxidative stress roles of TRPV4 inhibition during myocardial I/R and the application of exogenous H2O2. In conclusion, the inhibition of TRPV4 exerts cardioprotective effects through enhancing antioxidative enzyme activity and expressions via the Akt/Nrf2/ARE pathway.


Assuntos
Antioxidantes/metabolismo , Traumatismo por Reperfusão Miocárdica/tratamento farmacológico , Traumatismo por Reperfusão Miocárdica/metabolismo , Canais de Cátion TRPV/antagonistas & inibidores , Canais de Cátion TRPV/metabolismo , Animais , Elementos de Resposta Antioxidante/efeitos dos fármacos , Elementos de Resposta Antioxidante/genética , Catalase/metabolismo , Cromonas/farmacologia , Peróxido de Hidrogênio/metabolismo , Masculino , Morfolinas/farmacologia , Morfolinas/uso terapêutico , Fator 2 Relacionado a NF-E2 , Proteína Oncogênica v-akt/antagonistas & inibidores , Proteína Oncogênica v-akt/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Pirróis/uso terapêutico , Ratos , Ratos Sprague-Dawley , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais/efeitos dos fármacos , Superóxido Dismutase/metabolismo
13.
Dalton Trans ; 48(28): 10676-10682, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31241106

RESUMO

For perovskite ceramics, the ferroelectric phase boundary plays an important role in improving the piezoelectricity of the materials. In this work, (1 - x)(K0.5Na0.5)NbO3 - x[NaSbO3 + Bi0.5(Na0.8K0.2)0.5(Zr0.5Hf0.5)O3] lead-free ceramics with R-O-T ferroelectric phase coexistence were developed and the relationship between the phase structure and piezoelectricity was investigated in detail. As x increases, the transition temperature of the rhombohedral and orthorhombic phases (TR-O) increases, while the orthorhombic-tetragonal phase transition temperature (TO-T) decreases. When 0.04 ≤ x ≤ 0.05, three ferroelectric phases (R-O-T) coexist near room temperature in the ceramics. Due to the highly consistent orientation of the ferroelectric dipole and the free energy flattening and a low energy barrier induced by the coexistence of three ferroelectric phases (R-O-T), excellent piezoelectric performances of d33 = 452 pC N-1, kp = 63% and εr = 4414 are achieved at x = 0.04. Our study suggests that compared with two ferroelectric phase boundaries (R-O and O-T), the coexistence of the three ferroelectric phases (R-O-T) can effectively enhance the piezoelectric properties of (K0.5Na0.5)NbO3-based ceramics.

14.
Nutr Cancer ; 71(6): 908-921, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31044620

RESUMO

To evaluate the relationship between obesity, analyzed by different indicators, and lung cancer incidence, literature search was conducted in the PubMed, Web of Science, EBSCO, Ovid, and China National Knowledge Infrastructure databases for articles published until December 2018. Twenty-eight prospective cohort studies were identified, with 28 784,269 participants and 127,161 lung cancer cases were included in the analysis. The combined relative risks (RRs) with 95% CIs for the highest versus normal category of body mass index (BMI) were RR = 0.77 (95% CI: 0.72-0.82), but the inverse association disappeared for never smokers or small cell carcinoma after stratifying the smoking status or histological cancer types, respectively. Further analysis considered lag time and excluded the effects of preclinical cancer, there is no statistically significant inverse association between BMI and lung cancer risk, RR = 0.89 (95% CI: 0.66-1.19). In contrast, the combined RRs with 95% CIs for the highest versus lowest category of waist circumference (WC) were RR = 1.26 (95% CI: 1.14-1.39). Therefore, due to multiple confounders existed, BMI might not be an appropriate indicator for obesity when study lung cancer risk. The significantly positive relationship between WC and lung cancer risk indicated there might have an etiological connection between central obesity and lung cancer development.

15.
Anal Chem ; 91(13): 8289-8297, 2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31141341

RESUMO

Aptamers, short DNA or RNA oligonucleotides, which evolved from systematic evolution of ligands by exponential enrichment (SELEX), can perform specific target recognition. Papillary thyroid carcinoma (PTC) is of high incidence worldwide, and the prognosis of advanced PTC is poor. Up to now, there is no specific biomarker that can identify PTC and defects still remain in existing diagnostic methods. Here we report an aptamer, termed TC-6, which is generated from tissue-SELEX by using sections of papillary thyroid carcinoma and a normal thyroid gland. TC-6 could specifically target intracellular components of papillary thyroid cells with high affinity ( Kd = 57.66 ± 5.93 nmol/L) and have performed excellent biocompatibility both in vivo and in vitro. Moreover, fluorescence imaging of PTC tumor-bearing mice revealed that TC-6 was able to accumulate in tumor sites and could distinguish thyroid carcinoma from other benign thyroid diseases efficiently. In addition, TC-6d, a truncated aptamer of TC-6, maintained its affinity toward PTC with Kd of 39.20 ± 8.20 nmol/L. Overall, these results indicate that TC-6 is a potential candidate for developing novel tools for diagnosis and targeted therapy of PTC.

16.
Bioresour Technol ; 288: 121517, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31121527

RESUMO

This study was conducted to examine the effects of different bulking materials (corncob and ricehusk) on liquid manure consumption, organic matter degradation and pollutants retention in composting process under controlled addition of different types of liquid manures (LM). The results indicated that under the controlled addition of LM, bulking materials with higher content of biodegradable carbon (corncob) and LM with a higher concentration of organic pollutants (swine effluent) were more beneficial for biological heat generation and thus were more efficient for water evaporation, organic matter degradation, LM consumption and pollutants retention during the cocomposting process. Consequently, the optimization of these major influencing factors could compensate for efforts geared towards better utilization of the cocomposting process.


Assuntos
Compostagem , Poluentes Ambientais , Animais , Ingestão de Líquidos , Esterco , Solo , Suínos
17.
Wideochir Inne Tech Maloinwazyjne ; 14(1): 96-101, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30766635

RESUMO

Introduction: Even though transurethral resection of the prostate (TURP) is the standard surgical treatment for benign prostatic hyperplasia (BPH), there is a high rate of postoperative retrograde ejaculation. Aim: To evaluate the effectiveness of TURP with preservation of the bladder neck in comparison with that of standard TURP. Material and methods: This is a retrospective study. 137 men with BPH were divided into two groups: TURP with preservation of the bladder neck and standard TURP were performed respectively in group A and group B. The patients were evaluated preoperatively and at 3, 6 and 12 months after surgery by International Prostate Symptom Score (IPSS), health-related quality of life (HRQL) score, maximum urinary flow rate (Qmax), postvoid residual urine volume (PVR) and the rate of complications including retrograde ejaculation. Results: There was no statistically significant difference between groups in terms of the operative duration, catheterization period, hemoglobin decrease, and hospital stay. At the 3-month follow-up, the rates of incontinence and retrograde ejaculation in group A were lower than those in group B. At the 6- and 12-month follow-ups, the difference in the frequency of retrograde ejaculation remained constantly stable whereas the incontinence rates were similar in both groups. The IPSS, HRQL score, Qmax, PVR and the rate of complications including hematuria, clot retention, urinary tract infection, urethral stricture, and bladder neck contracture evaluated at 3, 6 and 12 months also displayed a very similar response in the two groups. Conclusions: Comparable with standard TURP, TURP with preservation of the bladder neck appears to provide a satisfactory clinical outcome in decreasing early postoperative incontinence and lowering the rate of retrograde ejaculation.

18.
J Biomed Mater Res A ; 107(7): 1491-1512, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30790423

RESUMO

Many factors have been demonstrated as having an influencing effect on the osteogenic activity of the peptide-modified bone repair materials. However, most of studies only focus on one or two aspects that result in an incomplete direction for materials preparation, characterization, and performance evaluation. In this review, we reported several factors through summarizing previous research studies, which are mainly centered on three aspects: (1) the characteristics of peptide immobilized on the surface of matrix (e.g., type and length of sequence, structure, and density); (2) the combination mode between peptide and matrix (including covalent binding in selective or nonselective immobilization, and noncovalent binding through simple absorption or mixing with the matrix, and other factors in covalent binding); and (3) the properties of the matrix (including surface structure and morphology, dimension, mechanical properties, hydrophobic-hydrophilic balance, adsorbing proteins on materials), and the other possible influencing factors such as binding to other peptides. In addition, attentions were paid to the introduction and the discussion of newest studies and the analysis of mechanism. © 2019 Wiley Periodicals, Inc. J Biomed Mater Res Part A, 2019.

19.
Bioresour Technol ; 275: 61-69, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30576915

RESUMO

This study was conducted to examine the effects of controlled addition of liquid (LM) to solid (SM) manure compost using a volume-model technique on the co-composting of SM and LM, and further to investigate the major effects of bulking material sizes and LM types on the co-composting process and final compost characteristics. Results indicated that this volume-model technique played a critical role in reducing leachate generation and improving the overall efficiency of the co-composting process. Specifically, the developed model enhanced the evaporation rates of windrows during the co-composting process. For improved final compost properties, small bulking materials and swine-effluent-based LM were found to be more efficient for organic matter degradation, LM consumption, hazardous metals immobilization, and essential nutrients retention than large bulking materials and biogas-based LM. Thus, process parameter optimizations represent major research options for successful co-composting applications for the future.


Assuntos
Compostagem , Poluentes Ambientais/metabolismo , Nutrientes/metabolismo , Animais , Biocombustíveis , Esterco , Suínos
20.
Matrix Biol ; 78-79: 255-271, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30098420

RESUMO

Acute lung injury results in early inflammation and respiratory distress, and later fibrosis. The glycosaminoglycan hyaluronan (HA) and the Receptor for Hyaluronan-Mediated Motility (RHAMM, CD168) have been implicated in the response to acute lung injury. We hypothesized that, compared to wild type (WT) mice, RHAMM knockout (KO) mice would be protected from, whereas mice with macrophage-specific transgenic overexpression of RHAMM (TG) would have worse inflammation, respiratory distress and fibrosis after intratracheal (IT) bleomycin. Compared to WT mice, 10 days after IT bleomycin, RHAMM KO mice had less weight loss, less increase in respiratory rate, and fewer CD45+ cells in the lung. At day 28, compared to injured WT animals, injured RHAMM KO mice had lower M1 macrophage content, as well as decreased fibrosis as determined by trichrome staining, Ashcroft scores and lung HPO content. Four lines of transgenic mice with selective overexpression of RHAMM in macrophages were generated using the Scavenger Receptor A promoter driving a myc-tagged full length RHAMM cDNA. Baseline expression of RHAMM and CD44 was the same in WT and TG mice. By flow cytometry, TG bone marrow-derived macrophages (BMDM) had increased cell surface RHAMM and myc, but equal CD44 expression. TG BMDM also had 2-fold increases in both chemotaxis to HA and proliferation in fetal bovine serum. In TG mice, increased inflammation after thioglycollate-induced peritonitis was restricted to macrophages and not neutrophils. For lung injury studies, non-transgenic mice given bleomycin had respiratory distress with increased respiratory rates from day 7 to 21. However, TG mice had higher respiratory rates from 4 days after bleomycin and continued to increase respiratory rates up to day 21. At 21 days after IT bleomycin, TG mice had increased lung macrophage accumulation. Lavage HA concentrations were 6-fold higher in injured WT mice, but 30-fold higher in injured TG mice. At 21 days after IT bleomycin, WT mice had developed fibrosis, but TG mice showed exaggerated fibrosis with increased Ashcroft scores and HPO content. We conclude that RHAMM is a critical component of the inflammatory response, respiratory distress and fibrosis after acute lung injury. We speculate that RHAMM is a potential therapeutic target to limit the consequences of acute lung injury.


Assuntos
Lesão Pulmonar Aguda/imunologia , Proteínas da Matriz Extracelular/genética , Proteínas da Matriz Extracelular/metabolismo , Receptores de Hialuronatos/genética , Receptores de Hialuronatos/metabolismo , Pulmão/imunologia , Lesão Pulmonar Aguda/induzido quimicamente , Lesão Pulmonar Aguda/genética , Lesão Pulmonar Aguda/metabolismo , Animais , Bleomicina/toxicidade , Modelos Animais de Doenças , Técnicas de Inativação de Genes , Humanos , Ácido Hialurônico/metabolismo , Pulmão/metabolismo , Macrófagos/metabolismo , Masculino , Camundongos Transgênicos
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