ABSTRACT Purpose: This study investigated the effects of oral administration of Clostridium butyricum (C. butyricum) on inflammation, oxidative stress, and gut flora in rats with hepatic ischemia reperfusion injury (HIRI). Methods: The rats from C. butyricum group were given C. butyricum for 5 days. Then, hepatic ischemia for 30 min and reperfusion for 6 h were performed in all the rats. After the animals were sacrificed, alanine transaminase (ALT), aspartate aminotransferase (AST), lipopolysaccharide (LPS) in serum, short-chain fatty acids (SCFAs), and gut microbiota composition in feces, and malondialdehyde (MDA), glutathione (GSH), tumor necrosis factor-α (TNF-α), interleukin 6 (IL-6), Toll-like receptor 4 (TLR4), nuclear factor-kappa Bp65 (NF-κBp65) and histological analysis in the liver were performed. Results: The rats given C. butyricum showed decreased ALT, AST, LPS, and MDA; improved GSH and histological damage; changes in SCFAs; declined TNF-α, IL-6, TLR4, and pNF-κBp65/NF-κBp65; and changes in the gut microbial composition, which decreased the Firmicutes/Bacteroidetes ratio and increased the relative abundance (RA) of probiotics. Conclusions: C. butyricum supplementation protected against HIRI by regulating gut microbial composition, which contributed to the decreased LPS and attenuation of inflammation and oxidative stress. These indicate C. butyricum may be a potent clinical preoperative dietary supplement for HIRI.

Resumo Fundamento: A doença cardiovascular é a principal causa de morte em todo o mundo. A apoptose mediada por hipóxia em cardiomiócitos é uma das principais causas de distúrbios cardiovasculares. O tratamento com a proteína do fator de crescimento endotelial vascular (VEGF, do inglês vascular endothelial growth factor) foi testado, mas as dificuldades operacionais limitaram seu uso. Entretanto, com os avanços da terapia gênica, aumentou o interesse na terapia gênica baseada no VEGF em doenças cardiovasculares. No entanto, o mecanismo preciso pelo qual a reposição de VEGF resgata os danos pós-hipóxia em cardiomiócitos não é conhecido. Objetivos: Investigar o efeito da expressão de VEGF121 pós-hipóxia utilizando cardiomiócitos de ratos neonatos. Métodos: Cardiomiócitos isolados de ratos neonatos foram utilizados para estabelecer um modelo in vitro de lesão cardíaca induzida por hipóxia. O efeito da superexpressão de VEGF, isolado ou em conjunto com inibidores de moléculas pequenas que têm como alvo os canais de cálcio, receptores sensíveis ao cálcio (CaSR, do inglês calcium-sensitive receptors) e calpaína, no crescimento e proliferação celular em lesão de cardiomiócitos induzidos por hipóxia, foram determinados com ensaio de MTT, coloração TUNEL, coloração com Anexina V/PI, lactato desidrogenase e atividade da caspase. Para análise estatística, um valor de p<0,05 foi considerado significativo. Resultados: Verificou-se que o efeito do VEGF121 foi mediado por CaSR e calpaína, mas não foi dependente dos canais de cálcio. Conclusões: Nossos resultados, mesmo em um ambiente in vitro, estabelecem as bases para uma validação futura e testes pré-clínicos da terapia gênica baseada em VEGF em doenças cardiovasculares.

Abstract Background: Cardiovascular disease is the major cause of death worldwide. Hypoxia-mediated apoptosis in cardiomyocytes is a major cause of cardiovascular disorders. Treatment with vascular endothelial growth factor (VEGF) protein has been tested but operational difficulties have limited its use. However, with the advancements of gene therapy, interest has risen in VEGF-based gene therapy in cardiovascular disorders. However, the precise mechanism by which VEGF replenishment rescues post-hypoxia damage in cardiomyocytes is not known. Objectives: To investigate the effect of post-hypoxia VEGF121 expression using neonatal rat cardiomyocytes. Methods: Cardiomyocytes isolated from neonatal rats were used to establish an in vitro model of hypoxia-induced cardiac injury. The effect of VEGF overexpression, alone or in combination with small-molecule inhibitors targeting calcium channel, calcium sensitive receptors (CaSR), and calpain on cell growth and proliferation on hypoxia-induced cardiomyocyte injury were determined using an MTT assay, TUNEL staining, Annexin V/PI staining, lactate dehydrogenase and caspase activity. For statistical analysis, a value of P<0.05 was considered to be significant. Results: The effect of VEGF121 was found to be mediated by CaSR and calpain but was not dependent on calcium channels. Conclusions: Our findings, even though using an in vitro setting, lay the foundation for future validation and pre-clinical testing of VEGF-based gene therapy in cardiovascular diseases.

This article focuses on the educational quality of the newly emerged quasi-state schools for rural migrant children in urban China. Semi-structured interviews were conducted with 19 government officers, school leaders, teachers and migrant parents in Shanghai. Adopting a theoretical perspective of policy as a temporary settlement of interests, the article deconstructs the power relations that constructed the disadvantaged positionality of these schools in the local school system. What can be identified from the empirical data is the emergence of an "interim quasi-state school system" with three interrelated features: it belongs to the state sector, offers quasi-state education and has an interim nature. Under the local government's low-cost and inferior schooling approach, the whole system is treated as an emergency mechanism for solving the floating children's schooling problem, rather than as regular schools offering high quality education. While realising the children's right to education, this system does not guarantee them a "good" education.

In this study, a bivariable coupling model for river channel routing is presented. The proposed model is developed from the Priessmann 4-point implicit differential scheme with a weight coefficient of river flow continuity equation. It is based on the transformation of two different expression forms of river channel storage equation. Furthermore, we consider the impact of lateral inflow along the study river channel from another perspective. In this paper we deduct lateral inflow from the lower section instead of adding lateral inflow to the upper section. In order to be representative of geographical range, river channel characteristics, flood magnitude, hydraulic characteristics and time, the proposed model is tested in 38 river channels of 6 river systems in China by using observed data during flood season. The rationality of model structure and the validity of model simulation are examined comprehensively. Comparison between the proposed model and Muskingum model shows that the proposed model can improve the simulation accuracy. The results show that the simulation accuracy and stability of the bivariable coupling model is much better than that of the Muskingum model.

SnO2 nanofibers were fabricated by calcination of the electrospun PVP/SnCl4 composite nanofibers. For the first time, SnS nanofibers and SnSe nanofibers were successfully synthesized by double-crucible sulfurization and selenidation methods via inheriting the morphology of SnO2 nanofibers used as precursors, respectively. X-ray diffraction (XRD) analysis shows SnS nanofibers and SnSe nanofibers are respectively pure orthorhombic phase with space group of Pbnm and Cmcm. Scanning electron microscope (SEM) observation indicates that the diameters of SnS nanofibers and SnSe nanofibers are respectively 140.54±12.80 nm and 96.52±14.17 nm under the 95 % confidence level. The photocatalytic activities of samples were studied by using rhodamine B (Rh B) as degradation agent. When SnS or SnSe nanofibers are employed as the photocatalysts, the respective degradation rates of Rh B solution under the ultraviolet light irradiation after 200 min irradiation are 92.55 % and 92.86 %. The photocatalytic mechanism and formation process of SnS and SnSe nanofibers are also provided. More importantly, this preparation technique is of universal significance to prepare other metal chalcogenides nanofibers.

ABSTRACT The objective of this research was to design a new colon-targeted drug delivery system based on chitosan. The properties of the films were studied to obtain useful information about the possible applications of composite films. The composite films were used in a bilayer system to investigate their feasibility as coating materials. Tensile strength, swelling degree, solubility, biodegradation degree, Fourier Transform Infrared Spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Scanning Electron Microscope (SEM) investigations showed that the composite film was formed when chitosan and gelatin were reacted jointly. The results showed that a 6:4 blend ratio was the optimal chitosan/gelatin blend ratio. In vitro drug release results indicated that the Eudragit- and chitosan/gelatin-bilayer coating system prevented drug release in simulated intestinal fluid (SIF) and simulated gastric fluid (SGF). However, the drug release from a bilayer-coated tablet in SCF increased over time, and the drug was almost completely released after 24h. Overall, colon-targeted drug delivery was achieved by using a chitosan/gelatin complex film and a multilayer coating system.

ABSTRACT This study highlights the prevalence of aminoglycoside-modifying enzyme genes and virulence determinants among clinical enterococci with high-level aminoglycoside resistance in Inner Mongolia, China. Screening for high-level aminoglycoside resistance against 117 enterococcal clinical isolates was performed using the agar-screening method. Out of the 117 enterococcal isolates, 46 were selected for further detection and determination of the distribution of aminoglycoside-modifying enzyme-encoding genes and virulence determinants using polymerase chain reaction -based methods. Enterococcus faecium and Enterococcus faecalis were identified as the species of greatest clinical importance. The aac(6')-Ie-aph(2")-Ia and ant(6')-Ia genes were found to be the most common aminoglycoside-modifying enzyme genes among high-level gentamicin resistance and high-level streptomycin resistance isolates, respectively. Moreover, gelE was the most common virulence gene among high-level aminoglycoside resistance isolates. Compared to Enterococcus faecium, Enterococcus faecalis harbored multiple virulence determinants. The results further indicated no correlation between aminoglycoside-modifying enzyme gene profiles and the distribution of virulence genes among the enterococcal isolates with high-level gentamicin resistance or high-level streptomycin resistance evaluated in our study.

RESUMO O objetivo desta pesquisa foi planejar um novo sistema de liberação de fármacos direcionado ao cólon, utilizando quitosana. Estudaram-se as propriedades dos filmes a fim de obter informações úteis sobre a aplicação desses filmes compósitos. Utilizaram-se os filmes compósitos em sistema de bicamada para investigar a sua viabilidade como materiais de revestimento. Estudos de resistência à tração, grau de intumescimento, solubilidade, grau de biodegradação, no infravermelho por transformada de Fourier (FTIR), de calorimetria diferencial de varredura (DSC) e de microscopia eletrônica de varredura (SEM) mostraram que o filme compósito se formou quando a quitosana e a gelatina reagiram entre si. Os resultados mostraram que a mistura de proporção ótima foi de 6:4 de quitosana:gelatina. Resultados da liberação do fármaco in vitro indicaram que o sistema de revestimento de Eudragit e bicamada de quitosana/gelatina impediu a liberação de fármaco em fluido intestinal simulado (SIF) e em fluido gástrico simulado (SGF). Entretanto, a liberação de fármaco do comprimido revestido em bicamada no SCF aumentou ao longo do tempo e o fármaco foi quase completamente liberado após 24 h. Em geral, se obteve a forma de liberação dirigida ao cólon, utilizando filme complexo de quitosana/gelatina e sistema de revestimento multicamada.

ABSTRACT The objective of this research was to design a new colon-targeted drug delivery system based on chitosan. The properties of the films were studied to obtain useful information about the possible applications of composite films. The composite films were used in a bilayer system to investigate their feasibility as coating materials. Tensile strength, swelling degree, solubility, biodegradation degree, Fourier transform infrared spectroscopy (FTIR), Differential Scanning Calorimetry (DSC), Scanning electron microscope (SEM) investigations showed that the composite film was formed when chitosan and gelatin were jointly reacted jointly. The results showed that a 6:4 blend ratio was the optimal chitosan/gelatin blend ratio. In vitro drug release results indicated that the Eudragit- and chitosan/gelatin-bilayer coating system prevented drug release in simulated intestinal fluid (SIF) and simulated gastric fluid (SGF). However, the drug release from a bilayer-coated tablet in SCF increased over time, and the drug was almost completely released after 24 h. Overall, colon-targeted drug delivery was achieved by using a chitosan/gelatin complex film and a multilayer coating system.