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1.
Anal Chim Acta ; 1118: 52-62, 2020 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-32418604

RESUMO

We have designed and synthesized a new luminescent mononuclear samarium (III) complex Sm-2h based on the [1 + 1] Schiff-base macrocycle H2L2h, derived from the cyclocondensation reaction between dialdehyde and diamine precursors, and its exact architecture is determined to be [Sm(HL2h) (NO3)2]. The sensing ability of complex Sm-2h is carefully evaluated for various common inorganic ions in solution. It is shown that complex Sm-2h is a multi-responsive fluorimetric sensor with high selectivity for F- and PO43- anions together with Zn2+ cation. The sensing process is rapid within 60 s for F- and PO43- ions and 300 s for Zn2+ ion. Further detailed responsive investigations suggest that its sensing behavior has excellent linear relationship between the fluorescence intensity (or absorption value) and ion concentration. The limit of detection (LOD) for sensing F-, PO43- and Zn2+ ions are as low as 2.61 µM (2.94 µM), 1.92 µM (1.64 µM) and 5.67 µM (3.53 µM), respectively, verified by fluorimetric (or colorimetric) titration experiments. ESI mass spectra prove that these efficient detections originate from the structure collapse of sensor Sm-2h because of the ion-induced imine bond breakage. Moreover, sensor Sm-2h shows excellent sensing performances for F-, PO43- and Zn2+ ions in real water samples, and we also have developed a convenient method to detect these three ions by use of the sensor impregnated test paper strips, providing rapid and distinguishable fluorimetric color changes. Therefore, the macrocyclic Sm(III) complex Sm-2h could be regarded as a valuable candidate for monitoring F-, PO43- and Zn2+ ions in practical applications.

2.
Int J Biol Macromol ; 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32470578

RESUMO

At present, more and more attention has been paid to the development of active wound dressings. Chitosan, a kind of carbohydrate polymer with good biocompatibility, is widely used in the field of wound dressings. In this study, a slopeing free surface electrospinning (SFSE) device was presented to prepare large quantities of polycaprolactone/chitosan/aloe vera (PCL/CS/AV) nanofiber membranes (NFMs) for antibacterial wound dressing. And the morphologies of PCL/CS/AV NFMs with varying weight ratios of PCL:CS:AV were studied using SEM, and the optimal weight ratio of 5:3:2 was determined for better wound dressings. Then the structure, wetting property and yield of the PCL/CS/AV NFMs with the optimal weight ratio were investigated, and the effects of the addition of AV on the antibacterial performance and the biocompatibility of NFMs was studied. In addition, the preparation mechanism of SFSE was researched by simulating the electric field distribution using Maxwell 3D due to the important role of the electric field in the SFSE process. The simulation analyses of electric fields agreed with the experimental data. The results illustrated SFSE could prepare high quality PCL/CS/AV NFMs in batches, and its yield of PCL/CS/AV NFMs was 10 times more than the single-needle ES, and the fabricated NFMs showed excellent antibacterial performance and biocompatibility, which made them suitable for wound dressings.

3.
ISME J ; 2020 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-32327733

RESUMO

Chlorine disinfection to drinking water plays an important role in preventing and controlling waterborne disease outbreaks globally. Nevertheless, little is known about why it enriches the antibiotic resistance genes (ARGs) in bacteria after chlorination. Here, ARGs released from killed antibiotic-resistant bacteria (ARB), and culturable chlorine-injured bacteria produced in the chlorination process as the recipient, were investigated to determine their contribution to the horizontal transfer of ARGs during disinfection treatment. We discovered Escherichia coli, Salmonella aberdeen, Pseudomonas aeruginosa and Enterococcus faecalis showed diverse resistance to sodium hypochlorite, and transferable RP4 could be released from killed sensitive donor consistently. Meanwhile, the survival of chlorine-tolerant injured bacteria with enhanced cell membrane permeabilisation and a strong oxidative stress-response demonstrated that a physiologically competent cell could be transferred by RP4 with an improved transformation frequency of up to 550 times compared with the corresponding untreated bacteria. Furthermore, the water quality factors involving chemical oxygen demand (CODMn), ammonium nitrogen and metal ions (Ca2+ and K+) could significantly promote above transformation frequency of released RP4 into injured E. faecalis. Our findings demonstrated that the chlorination process promoted the horizontal transfer of plasmids by natural transformation, which resulted in the exchange of ARGs across bacterial genera and the emergence of new ARB, as well as the transfer of chlorine-injured opportunistic pathogen from non-ARB to ARB. Considering that the transfer elements were quite resistant to degradation through disinfection, this situation poses a potential risk to public health.

4.
Plant Sci ; 294: 110433, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32234222

RESUMO

Triterpenoids produced by the secondary metabolism of Betula platyphylla Suk. exhibit important pharmacological activities, such as tumor inhibition, anti-HIV, and defense against pathogens, but the yield of natural synthesis is low, which is insufficient to meet people's needs. In this study, we identified two OSC genes of birch, named as BpCAS and Bpß-AS, respectively. The expression of BpCAS and Bpß-AS were higher levels in roots and in stems, respectively, and they induced expression in response to methyl jasmonate (MeJA), gibberellin (GA3), abscisic acid (ABA), ethylene and mechanical damage. The function of the two genes in the triterpene synthesis of birch was identified by reverse genetics. The inhibition of Bpß-AS gene positively regulates synthesis of betulinic acid. BpCAS interference can significantly promote the upregulation of lupeol synthase gene (BPW) and ß-amyrin synthase gene(BPY), and conversion of 2,3-oxidosqualene to the downstream products betulinic acid and oleanolic acid. This study provided a basis for the genetic improvement of triterpenoid synthesis in birch through genetic engineering. The obtained transgenic birch and suspension cells served as material resources for birch triterpenoid applications in further.

6.
Ecotoxicol Environ Saf ; 195: 110461, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32182530

RESUMO

Antibiotic residues in the environment pose a great risk to global public health. They increase antibiotic resistance by enhancing plasmid conjugation among bacteria or mutations within bacterial genomes. However, little is known about whether the putative environmental levels of antibiotics are sufficient to influence plasmid-mediated transformability. In this study, we explored the effect of eight kinds of representative antibiotics and several other compounds on the plasmid transformability of competent Escherichia coli. Only levofloxacin (LEV) at the putative environmental levels was found to facilitate the frequency of PBR322-or RP4-plasmid-mediated transformation by up to 5.3-fold. Additionally, PBR322 transformation frequency could be further enhanced by copper ion or ammonia nitrogen but inhibited by humic acid. However, when competent E. coli was exposed to the minimal inhibitory concentrations (MIC) of the antibiotics, an enhanced plasmid-assimilation ability was observed and plasmid transformation frequency was increased by up to 98.6-fold for all the tested antibiotics. Furthermore, E. coli exhibited a preference for the uptake of plasmids harbouring the resistance genes to the antibiotics it had been exposed to. Among these antibiotics, cephalexin, tetracycline, and kanamycin induced the highest uptake of RP4. The putative environmental levels of LEV enhanced plasmid transformability regardless of the presence of corresponding antibiotic resistance gene (ARG) on the genetic elements, suggesting environmental LEV residues may facilitate dissemination of antibiotic resistance by any plasmid-mediated transformability, thereby posing a great risk to health.

7.
Medicine (Baltimore) ; 99(5): e18851, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32000386

RESUMO

BACKGROUND: The pathogenesis of cervical spondylotic is degenerative changes of the cervical intervertebral disc, or bone hyperplasia of the posterior and hook joints, and instability of the joints of the cervical vertebrae. It causes the nerve roots to be stimulated and oppressed. The clinical manifestations are the sensation, movement, and reflex disorder of the cervical spinal nerve roots that are stimulated and oppressed, especially the numbness and pain of the neck, shoulders, upper limbs, and fingers. In this systematic review, we aimed to evaluate the efficacy and safety of acupuncture and chiropractic in the treatment of cervical spondylotic. METHODS AND ANALYSIS: We will search for PubMed, Cochrane Library, AMED, Embase, WorldSciNet; Nature, Science online and China Journal Full-text Database (CNKI), China Biomedical Literature CD-ROM Database (CBM), and related randomized controlled trials included in the China Resources Database. The time is limited from the construction of the library to September 2019. We will use the criteria provided by Cochrane 5.1.0 for quality assessment and risk assessment of the included studies, and use the RevMan 5.3 and Stata 13.0 software for meta-analysis of the effectiveness, recurrence rate, and symptom scores of cervical spondylotic. ETHICS AND DISSEMINATION: This systematic review will evaluate the efficacy and safety of acupuncture and chiropractic for cervical spondylotic. Because all of the data used in this systematic review and meta-analysis have been published, this review does not require ethical approval. Furthermore, all data will be analyzed anonymously during the review process trial.


Assuntos
Terapia por Acupuntura , Manipulação Quiroprática , Radiculopatia/terapia , Humanos , Radiculopatia/etiologia , Espondilose/complicações
8.
Arch Environ Contam Toxicol ; 78(4): 622-630, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32060565

RESUMO

Twenty-eight transects in six urban rivers located in the Qianhai area of Baoan District, Shenzhen, China, were selected to study the contamination of heavy metals in its sediment, reveal the spatial distribution of heavy metals in these rivers, and assess the ecological risk of heavy metals in the urban river sediment. The result showed that the concentration of heavy metals displayed considerable variation in the study area. The results showed that southern airport drainage river had exposure to high concentrations of Cu, Nanchang Chung exposure to high concentrations of Zn, Cr, and Pb, Gongle Chung exposure to high concentrations of Ni, and Xixiang River exposure to high concentrations of Hg. The results of correlation analysis and cluster analysis indicated that Cu had significant correlations with Zn and Cr respectively (P < 0.05). There was significant correlation, and the same cluster existed among Zn, Cr, and Pb (P < 0.01), whereas Hg was not significantly correlated with other metals. The potential risk of the six rivers could be sorted as Gushu Chung < Gongle Chung < Tiegang reservoir flood discharge river < Xixiang River (a), Nanchang Chung < and Southern Airport drainage river.


Assuntos
Monitoramento Ambiental/métodos , Estuários , Sedimentos Geológicos/química , Metais Pesados/análise , Rios/química , Poluentes Químicos da Água/análise , China , Cidades , Análise por Conglomerados , Ecologia , Medição de Risco , Análise Espacial
9.
Medicine (Baltimore) ; 99(4): e18887, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31977897

RESUMO

INTRODUCTION: MYH9-related disease (MYH9-RD) is a rare autosomal dominant disorder caused by mutations in MYH9, which is responsible for encoding nonmuscle myosin heavy chains IIA (NMMHCIIA). MYH9-RD is clinically characterized by congenital macrothrombocytopenia, granulocyte inclusions variably associated with the risk of developing progressive sensorineural deafness, cataracts and nephropathy. PATIENT CONCERNS: A 5-year-old boy had a history of a mild bleeding tendency and chronic thrombocytopenia, first identified at four months of age. No other family members were noted to have similar clinical features or hematologic disorders. DIAGNOSES: The boy was diagnosed with MYH9-RD. Light microscopic examination of peripheral blood films (Wright-Giemsa stain) showed marked platelet macrocytosis with giant platelets and basophilic Döhle-like inclusions in 83% of the neutrophils. Immunofluorescence analysis disclosed a type II pattern, manifested by neutrophils which contained several circle-to-oval shaped cytoplasmic NMMMHCA-positive granules. Sequencing analysis of MYH9-RD genes was carried out and revealed a novel missense mutation of c.97T>G (p.W33G) in the patient but not in his parents. INTERVENTION: No treatment is necessary. Recognition of MYH9-RD is important to Avoiding unnecessary and potentially harmful treatments. OUTCOMES: The patient's condition remained stable during the follow-up. CONCLUSIONS: As a result of identifying this missense mutation in this particular case, we have added c.97T>G (p.W33G) to the broad spectrum of potential MYH9 mutations.


Assuntos
Perda Auditiva Neurossensorial/genética , Trombocitopenia/congênito , Pré-Escolar , Imunofluorescência , Perda Auditiva Neurossensorial/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Mutação de Sentido Incorreto , Neutrófilos/patologia , Trombocitopenia/diagnóstico , Trombocitopenia/genética
11.
J Acoust Soc Am ; 146(4): 2482, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31671957

RESUMO

Many underwater acoustic (UWA) channels exhibit impulsive noise, thereby severely degrading the performance of traditional channel estimation algorithms. This paper presents two channel estimation algorithms for impulsive noise, namely (i) the variable forgetting factor l1,0 recursive least sign algorithm (VFF-l1,0-RLSA) and (ii) the variable forgetting factor l2,0 recursive least sign algorithm (VFF-l2,0-RLSA), both of which exploit the group sparse multipath structure and maintain robustness under impulsive noise. By using the l1 norm of the estimation error as part of the cost function, RLSAs are better at detecting and rejecting impulsive noise than the recursive least squares algorithms. A mixed l1,0 or l2,0 norm is incorporated with a RLSA to achieve better performance in group sparse UWA channel estimation. The time-varying forgetting factor and regularization parameter in the two proposed algorithms help to improve their performance. Simulation results based on Arctic ice cracking noise demonstrate the robustness and superiority of the two proposed algorithms.

12.
ACS Omega ; 4(19): 18334-18341, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-31720535

RESUMO

Here, we report our trials to regulate the luminescence performance of the macrocyclic samarium(III) complex and prepare four excellent luminescent Sm(III) complex-doped poly(methylmethacrylate) (PMMA) composites. Four 23-membered [1 + 1] Schiff-base macrocyclic mononuclear Sm(III) complexes, Sm-2 a -Sm-2 d , originating from dialdehydes with different pendant arms and 1,2-bis(2-aminoethoxy)ethane, have been constructed by the template method. Crystal structures reveal that every Sm(III) ion with the coordination geometry of a distorted bicapped square antiprism is capsulated by the macrocyclic cavity environment forming the "lasso-type" protection. Relative photophysical properties of macrocyclic Sm(III) complexes are carefully investigated in solid-state, methanol solution, and doped PMMA film, and all these show characteristic emissions of the Sm(III) ion associated with satisfactory lifetimes and quantum yields in all media, which could be comparable to reported outstanding examples. Especially, the luminescence performance for this type of Sm(III) complex could be regulated in the solid state by the use of different functional groups in the pendant arm while it is not achieved in solution and the doped PMMA composite. High emitting and air-stable plastic materials could be obtained when these Sm(III) complexes are doped in PMMA with 0.1 wt % mixing ratio, and the corresponding maximum lifetime and quantum yield are 61.2 µs and 0.63% in the case of complex Sm-2 a , respectively. We believe that these highly luminescent "lasso-type" Sm(III) complexes and doped PMMA composites are valuable references in the design of luminescent lanthanide(III) hybrid materials.

13.
Analyst ; 144(17): 5254-5260, 2019 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-31364615

RESUMO

In this paper we report a novel probe based on a luminescent 23-membered [1 + 1] Schiff-base macrocyclic mononuclear Sm(iii) complex Sm-2e, originating from the dialdehyde H2Qe and 1,2-bis(2-aminoethoxy)ethane precursors, which is synthesized by the Sm(iii) ion template method. X-ray structural analyses confirm that each ten-coordinate Sm(iii) center with the coordination geometry of a distorted bicapped square antiprism is fully encapsulated by a flexible macrocyclic ligand H2L2e to form a "lasso-type" architecture, and this architecture could enable efficient energy transfer in various solvents confirmed by long lifetimes (33.5-65.2 µs) and high quantum yields (0.23-0.76%) of the Sm(iii) ion. Simultaneously, complex Sm-2e could serve as a probe for sensing organic solvents. Particularly, this complex probe Sm-2e exhibits a highly selective, rapid and sensitive response to tetrahydrofuran (THF), which is easily distinguished by a large absorption shift, even visible to the naked eye, and complete fluorescence quenching. Moreover, the limit of detection for THF is about 0.20% determined by titration experiments, and good selectivity for THF could still be realized in mixture solvents. Consequently, this colorimetric and "turn off" fluorescent probe Sm-2e could be a valuable candidate as a sensor material for sensing THF which has been rarely reported.


Assuntos
Complexos de Coordenação/química , Corantes Fluorescentes/química , Furanos/análise , Colorimetria/métodos , Complexos de Coordenação/síntese química , Fluorescência , Corantes Fluorescentes/síntese química , Limite de Detecção , Samário/química , Bases de Schiff/síntese química , Bases de Schiff/química , Espectrometria de Fluorescência/métodos
14.
Environ Sci Pollut Res Int ; 26(29): 29917-29929, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31410836

RESUMO

Phosphorus (P), an irreplaceable nutrient for all living organisms, is facing scarcity via phosphate resources. In this research, the effect of suitable additives and temperature on P and heavy metals speciation during sewage sludge (SS) thermochemical treatment was investigated. The results demonstrated that additives (CaO and MgO) could promote the conversion of non-apatite inorganic phosphorus (NAIP) to apatite phosphorus (AP). X-ray diffraction measurements indicated that the phosphorus mineral phase in sewage sludge ash (SSA) mainly was AP, with addition of MgO and CaO. Moreover, orthogonal testing revealed that the optimal molar ratio of Mg:Ca:P for P recovery as AP was 1:3.5:1 at 750 °C. Risk index results implied that the heavy metals in the phosphorus-enriched SSA have low potential ecological risk. Thermodynamic equilibrium calculations revealed that P reacted with the other metal ions was in the following order: Ca2+ > Mg2+ > Al3+ > Fe3+ > Zn2+ > K+. Graphical Abstract.


Assuntos
Incineração/métodos , Metais Pesados/química , Fosfatos/química , Fósforo/química , Esgotos/química , Apatitas/química , Temperatura Alta , Difração de Raios X
15.
World Neurosurg ; 131: e521-e529, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31394362

RESUMO

BACKGROUND: Spinal cord stimulation (SCS), a common invasive neuromodulation technique, induces pain relief via electrical stimulation of the dorsal column of the spinal cord. To present an overview of research publications on SCS, a bibliometric analysis of scientific publications from 1998 to 2017 was performed. METHODS: The relevant data were obtained from the Web of Science and PubMed database. These articles were classified into several categories, such as total number, countries, institutions, authors, and citations reports. The analysis of co-occurrence key words was handled by VOSviewer software. RESULTS: We found that there existed an increasing trend in the number of publications on SCS between 1998 and 2017. Among these countries, the United States published the largest number of papers in the past 20 years. Case Western Reserve University in the United States contributed the most publications. Among all research categories, neuroscience neurology was the most common area. In addition, regarding article types, basic research comprised a great proportion of the total papers on SCS in the PubMed database. The author V. Reggie Edgerton from the United States was the most-frequent contributor among the authors. The results showed that "spinal cord," "stimulation," and "pain" were the most common key words in the past 20 years. CONCLUSIONS: This bibliometric analysis first provides a basic overview of research publications on SCS published during the last 2 decades. Considering the expanded indications of SCS, there are a lot of things to do, and various countries should increase support to complete high-quality SCS studies.


Assuntos
Pesquisa Biomédica/tendências , Manejo da Dor , Dor , Estimulação da Medula Espinal , Bibliometria , Humanos , Editoração/tendências , Estados Unidos
16.
Biomed Opt Express ; 10(8): 3789-3799, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31452975

RESUMO

We theoretically and experimentally demonstrate a label-free terahertz biosensor with ultrahigh sensitivity and distinctive discretion. By constructing a metal-air-metal (MAM) metamaterial perfect absorber (MPA) with a metallic paired-ring resonator array, a hollow microfluidic channel, and a backed reflector, a novel dual-band absorptive sensing platform is proposed in the THz range. The near field coupling by dipole-induced trapped modes and the magnetic momentum caused a vertical to transverse power flux that dramatically enhanced the electromagnetic field on top of the metasurface and in the microfluidic channel, respectively. Both the resonant modes exhibit perfect absorption and produce ultrahigh normalized sensitivities of 0.47/RIU (refractive index unit, RIU) and 0.51/RIU at 0.76 THz and 1.28 THz, respectively. Compared with conventional microfluidic sensors, the salient advantages of our design are the perfect spatial overlap for light-matter interaction and polarization insensitivity. Characterized by THz time domain spectroscopic absorption quantification measurements with different concentrations of bovine serum albumin (BSA), the proposed sensor exhibits promising applications in microfluidic biosensing.

17.
Ecotoxicol Environ Saf ; 183: 109461, 2019 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-31377519

RESUMO

The present work investigated the changes in DNA methylation pattern of Tenebrio molitor mitochondria genome at different development stages, which was fed with polyurethane foam as a sole diet. Polyurethane foam could influence the global methylation levels in mitochondria DNA of Tenebrio molitor. Different leves of 5-methylcytosine appeared at CpG and non-CpG sites of Tenebrio molitor mtDNA while they were fed with polyurethane foam: 10 CpG and 49 non-CpG sites at larval stage, 4 CpG and 31 non-CpG sites at pupa stage, 7 CpG and 56 non-CpG sites at adult stage in general. Moreover, we observed the decreased levels of ATP generation with the mitochondria DNA methylation variation. The results demonstrated that mitochondria DNA gene could be methylated in response to environmental pollutants to modulate stage-specific functions. Moreover, mtDNA methylation of polyurethane-foam-feeding Tenebrio molitor existed discrepancy in the developmental stage. The tentative methylation mechanism of mtDNA might be that polyurethane foam induced oxidative stress and increased the permeability of mitochondrial membranes, which resulted in transmethylase entry into mitochondria.


Assuntos
DNA Mitocondrial/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Epigênese Genética/efeitos dos fármacos , Metamorfose Biológica/efeitos dos fármacos , Poliuretanos/toxicidade , Tenebrio/efeitos dos fármacos , 5-Metilcitosina/metabolismo , Animais , Metilação de DNA/efeitos dos fármacos , Larva/efeitos dos fármacos , Larva/genética , Metamorfose Biológica/genética , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/genética , Pupa/efeitos dos fármacos , Pupa/genética , Tenebrio/genética , Tenebrio/crescimento & desenvolvimento
18.
Artigo em Inglês | MEDLINE | ID: mdl-31320912

RESUMO

Aim: Chronic atrophic gastritis (CAG), the precancerous lesions of gastric cancer, plays an important role in the stepwise process of gastric cancer. The ancient Chinese medicine believes in that Qi deficiency and blood stasis are involved in the pathogenesis of CAG. Weiqi decoction, a classical formula from Longhua Hospital, could supplement Qi and activate blood circulation of human beings and has been used for treating CAG in clinic over twenty years. The study aims to clarify the effect and underlying molecular mechanism of Weiqi decoction on CAG rats. Methods: Forty-eight male Wistar rats were divided randomly into six groups: control group, model group, folic acid group, and WQD-treated groups at doses of 4 g/kg, 2 g/kg, and 1 g/kg, with eight rats in each group. MNNG and saturated NaCl were used to induce CAG rat with precancerous lesion (intestinal metaplasia and dysplasia). After 40 weeks, gastric mucosal blood flow was measured using Laser Doppler Flowmetry. The pathological changes of the gastric mucosa were identified by H&E staining and AB-PAS staining. The protein expression of COX-2, HIF-1α, VEGFR1, VEGFR2, Ki67, and cleaved caspase 3 in the gastric tissues was measured by western blotting approach. Gene expression of COX-2, HIF-1α, VEGF, VEGFR1, VEGFR2, Ang-1, and Ang-2 was detected by using Quantitative PCR method. The PGE2 concentrations in serum were detected by ELISA method. The protein expression of Ki67 in gastric mucosa was also detected by immunohistochemistry. Results: Compared with control rats, atrophy and intestinal metaplasia as well as the microcirculation disturbance of gastric mucosa were induced in the stomach of CAG rats identified by the H&E and AB-PAS staining as well as microcirculation measurement, which could be significantly attenuated by WQD treatment. Moreover, compared with the control group, the protein and gene expression of COX-2, HIF-1α, VEGFR1, and VEGFR2 in gastric tissues of pylorus was obviously increased and the serum PGE2 level was significantly deceased in CAG rats, which could be significantly counteracted by WQD administration. However, the gene expression of Ang-1 and Ang-2 was not significant difference between control rats and CAG rats, and WQD also had no significant effect on the gene expression of Ang-1 and Ang-2. Furthermore, the increased cell proliferation marked by upregulated protein expression of Ki67 and decreased cell apoptosis marked by downregulated protein expression of cleaved caspase 3 in stomach of pylorus in CAG rats were obviously reversed by WQD treatment. Conclusion: WQD attenuated CAG with precancerous lesion through regulating gastric mucosal blood flow disturbance and HIF-1α signaling pathway.

19.
Zhongguo Gu Shang ; 32(6): 519-523, 2019 Jun 25.
Artigo em Chinês | MEDLINE | ID: mdl-31277534

RESUMO

OBJECTIVE: To analyze the displacement, stress and mechanism of lumbosacral joint disorder patients after bending and standing manipulation in the finite element model. METHODS: A three-dimensional finite element model of a patient with lumbosacral joint disorder was established. The finite element analysis method was used to observe and analyze the three loading conditions of the model:axial, 34 degree inclined upward and vertical upward. RESULTS: In the lumbosacral joint disorder model, the L5 vertebral body was concentrated in the middle of the lower endplate, the intervertebral disc was concentrated in the center of the intervertebral disc, and the stress of S1 and related structures were concentrated in the anterior and posterior edges of the vertebral body. After simulated manipulation, stress mainly concentrated in the anterior, posterior and central circular areas of L5 vertebral upper endplate. The posterior structures of vertebral body concentrated in the ventral part of pedicle, isthmus and dorsal part of lamina. The stress of intervertebral disc dispersed in the posterior edge of vertebral body. Displacement results:In the lumbosacral joint disorder model, the left transverse process, the upper and lower articular process and the left part of spinous process were significantly displaced to the left, and the intervertebral disc was protruded forward. After simulated manipulation, the lower notch of L5 vertebral body moved forward and upward; the area of intervertebral foramen increased; the inferior articular process of L5 vertebral body moved forward; the superior articular process of sacrum moved forward and downward; the distance of articular process joints increased; and the displacement of sacrum concentrated on the posterior edge of vertebral body and the median sacral crest. CONCLUSIONS: Successful lumbosacral joint modeling can be carried out by finite element analysis, and the mechanism of bending and erecting manipulation is clear, which is effective and safe for the treatment of lumbosacral joint disorders.


Assuntos
Disco Intervertebral , Vértebras Lombares , Fenômenos Biomecânicos , Análise de Elementos Finitos , Humanos , Região Lombossacral , Sacro
20.
Biomed Environ Sci ; 32(5): 324-333, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31217049

RESUMO

OBJECTIVE: To investigate the mechanisms underlying ozone-induced inactivation of poliovirus type 1 (PV1). METHODS: We used cell culture, long-overlapping RT-PCR, and spot hybridization assays to verify and accurately locate the sites of action of ozone that cause PV1 inactivation. We also employed recombinant viral genome RNA infection models to confirm our observations. RESULTS: Our results indicated that ozone inactivated PV1 primarily by disrupting the 5'-non-coding region (5'-NCR) of the PV1 genome. Further study revealed that ozone specifically damaged the 80-124 nucleotide (nt) region in the 5'-NCR. Recombinant viral genome RNA infection models confirmed that PV1 lacking this region was non-infectious. CONCLUSION: In this study, we not only elucidated the mechanisms by which ozone induces PV1 inactivation but also determined that the 80-124 nt region in the 5'-NCR is targeted by ozone to achieve this inactivation.


Assuntos
Genoma Viral/efeitos dos fármacos , Oxidantes Fotoquímicos/farmacologia , Ozônio/farmacologia , Poliovirus/efeitos dos fármacos , Inativação de Vírus , Regiões 5' não Traduzidas , Animais , Células Vero
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