Comprehensive analysis of insulin products complex disulfide bonds structure by high resolution mass spectrum / 药学学报

The correct pairing of disulfide bonds maintains the correct folding mode and high-level structure formation of peptides and protein drugs, which is crucial for the quality control of products. In order to ensure that the disulfide bonds are correctly paired, disulfide bond analysis is an essential part of peptides and protein drug characterization. Mass spectrometry can be used to analyze disulfide bonds. However, insulin and its analogues have two pairs of disulfide bonds without restriction enzyme cutting site. Conventional collision-induced dissociation (CID) and high-energy induced cleavage (HCD) cannot accurately locate the complex disulfide bond. In our study, three methods were used to localize the complex disulfide, including enzyme digestion combined with key peptide fragment in source decay (ISD) fragmentation method, enzyme digestion combined with partial reduction alkylation method, intact protein source ISD and electron transfer dissociation (ETD) cleavage method, The applicability of insulin aspart, insulin lispro and insulin glargine were also investigated. This study provides a new way for the quality control of disulfide bonding mode of insulin and its analogues, and also provides a reference for the disulfide bond localization of peptides or proteins containing this complex disulfide bond.

Preheated acid associated with silane and electric current in the adhesion of the resin cement to ceramic

Abstract This study verified the effect of the combination of preheated hydrofluoric acid/silane/electric current in the adhesion of the resin cement to ceramic. IPS E.max Press ceramic discs embedded in PVC rigid tubes were divided into four groups associating preheated hydrofluoric acid and silane applied with electrical current (n=10): Ha+S (Heated acid + silane); Ha+S+Ec (Heated acid + silane + electrical current); A+S (Acid + silane) and A+S+Ec (Acid + silano + electrical current). Resin cement/ceramic samples were stored in water at 37°C for 24h. After storage, they were submitted to the microshear test, fracture analysis, and contact angle at 24h or after thermocycling (10,000 cycles/5-55ºC). Bond strength data were evaluated by two-way ANOVA. For comparison between evaluation times (24h or thermocycling) was applied unpaired t-test. A significance post-hoc test of p=0.05 was assumed for analyses and graphs (GraphPad Prism 9.0 software). At 24h, the microshear strength showed similar values between Ha+S, Ha+S+Ec, and A+S+Ec groups, while A+S showed the lowest value with a statistical difference. After thermocycling, Ha+S and Ha+S+Ec were similar, as well as A+S and A+S+Ec. There was a significant difference in all groups comparing 24h (highest value) with after thermocycling (lowest value). Adhesive fracture was predominant in all groups and evaluation times. Ha+S and A+S groups showed higher contact angle values compared to the Ha+S+Ec and A+S+Ec with lower values. In conclusion, the association of preheated hydrofluoric acid/silane applied or not with electric current promoted different microshear strength values, fracture types, and contact angles in the resin cement/ceramic bond.

Resumo Este estudo verificou o efeito da combinação ácido fluorídrico pré-aquecido/silano/corrente elétrica na adesão do cimento resinoso à cerâmica. Os discos cerâmicos IPS E.max Press embutidos em tubos rígidos de PVC foram separados em quatro grupos associando ácido fluorídrico pré-aquecido e silano aplicado com corrente elétrica (n=10): Ha+S (ácido aquecido + silano); Ha+S+Ec (Ácido aquecido + silano + corrente elétrica); A+S (Ácido + silano) e A+S+EC (Ácido + silano + corrente elétrica). Amostras de cimento resinoso/cerâmica foram armazenadas em água a 37°C por 24 horas. Após o armazenamento foram submetidas ao ensaio de micro cisalhamento, análise de fratura e ângulo de contato no período de 24 horas ou após termociclagem (10.000 ciclos/5-55ºC). Os dados de resistência de união foram avaliados por ANOVA dois fatores. Para comparação entre os tempos de avaliação (24 horas ou termociclagem) foi aplicado o teste t não pareado. Foi assumida significância de 5% para análises e gráficos (software GraphPad Prism 9.0). Em 24 horas, a resistência ao micro cisalhamento apresentou valores similares entre os grupos Ha+S, Ha+S+Ec e A+S+Ec, enquanto A+S apresentou menor valor com diferença estatística. Após a termociclagem, Ha+S e Ha+S+Ec foram similares, assim como A+S e A+S+Ec. Houve diferença significativa em todos os grupos comparando 24 horas (maior valor) com após termociclagem (menor valor). A fratura adesiva foi predominante em todos os grupos e tempos de avaliação. Os grupos Ha+S e A+S apresentaram maiores valores de ângulos de contato comparados aos grupos Ha+S+Ec e A+S+Ec com valores menores. Em conclusão, a associação ácido fluorídrico pré-aquecido/silano aplicado com corrente elétrica promoveu diferentes valores de resistência ao micro cisalhamento, tipos de fratura e ângulos de contato na adesão do cimento resinoso à cerâmica.

Effect of Ceramic Thickness on the Bond Strength to Resin-Luting Agents before and after Thermal Cycling

Abstract This study investigated microshear bond strength (µSBS) of two (2) dual-cured resin-luting agents (RelyX™ Ultimate and RelyX™ U200) when photoactivated through varying thicknesses of lithium disilicate, with or without thermal cycling. Discs of IPS e.max Press of 0.5, 1.5, and 2 mm in thickness were obtained. Elastomer molds (3.0 mm in thickness) with four cylinder-shaped orifices 1.0 mm in diameter, were placed onto the ceramic surfaces and filled with resin-luting agents. A Mylar strip, glass plate, and load of 250 grams were placed over the filled mold. The load was removed and the resin-luting agents were photoactivated through the ceramics using a single-peak LED (Radii Plus.) All samples were stored in distilled water at 37oC for 24 h. Half of the samples were subjected to thermal cycling (3,000 cycles; 5ºC and 55ºC). All samples were then submitted to µSBS test using a universal testing machine (Instron 4411) at a crosshead speed of 0.5 mm/min. Data were submitted to three-way ANOVA and Tukey post-hoc test (α=0.05). The mean µSBS at 24 h was significantly higher than after thermal cycling (p<0.05). No statistical difference was found between resin-luting agents (p > 0.05). The mean µSBS for groups photoactivated through 0.5 mm ceramic were significantly higher than 1.5 mm and 2.0 mm (p < 0.05). In conclusion, increased ceramic thicknesses reduced the bond strength of tested resin-luting agents to lithium disilicate. No differences were found between resin-luting agents. Thermal cycling reduced the bond strength of both resin-luting agents.

Resumo: Este estudo investigou a resistência de união ao microcisalhamento (RUµC) de dois (2) agentes de cimentação de resina dual (RelyX™ Ultimate e RelyX™ U200) quando fotoativados através de diferentes espessuras de dissilicato de lítio, com ou sem ciclagem térmica. Discos do IPS e.max Press de 0,5, 1,5 e 2 mm de espessura foram obtidos. Moldes de elastômero (3,0 mm de espessura) com quatro orifícios cilíndricos de 1,0 mm de diâmetro foram colocados sobre as superfícies cerâmicas e preenchidos com agentes de cimentação de resina. Uma tira Mylar, placa de vidro e carga de 250 gramas foram colocadas sobre o molde preenchido. A carga foi removida e os agentes de cimentação resinosos foram fotoativados através da cerâmica usando um LED de pico-único (Radii Plus). Todas as amostras foram armazenadas em água deionizada a 37oC por 24 h. Metade das amostras foi submetida a ciclagem térmica (3.000 ciclos; 5ºC e 55ºC). Todas as amostras foram então submetidas ao teste de RUµC usando uma máquina de teste universal (Instron 4411) com velocidade de 0,5 mm/min. Os dados foram submetidos à Análise de Variância três fatores e ao teste post-hoc de Tukey (α = 0,05). A média de RUµC em 24 h foi significativamente maior do que após a ciclagem térmica (p < 0,05). Não houve diferença estatística entre os cimentos resinosos (p > 0,05). As médias de RUµC para grupos fotoativados através de cerâmica de 0,5 mm foram significativamente maiores do que 1,5 mm e 2,0 mm (p < 0,05). Em conclusão, o aumento da espessura da cerâmica reduziu a resistência de união dos agentes de cimentação resinosos ao dissilicato de lítio. Não foram encontradas diferenças entre os agentes de cimentação resinosos. A ciclagem térmica reduziu a resistência de união de ambos os agentes de cimentação resinosos.

Evaluation the stress distribution in root canals by 3D finite element analysis after the materials used in reattaching the vertically root fractured fragments

Abstract The aim was to evaluate the effect of stress distribution on vertical, horizontal, and oblique forces on the tooth model after reattaching the fragments of the maxillary incisor with vertical root fracture (VRF) using different materials, by 3D finite element analysis (FEA). Tooth with a root canal, spongious, and cortical bone models were designed. VRF was modeled on a tooth with 4 different re-attachment models: Group 1: dual-cure cement (DC)+fiber reinforced composite (FRC), Group 2: DC+polyethylene fiber, Group 3: DC+glass fiber, and Group 4:DC. 100 N force was applied in 3 different directions. Maximum principal stresses (σmax) of dentin, and re-attachment materials were evaluated on colored images. The highest σmax values ​​were on the repair materials under vertical forces for Groups 1 and 4, respectively; Groups 2 and 3 showed similarity. The highest σmax values in repair materials under horizontal and oblique forces were observed in Group 3 however the lowest σmax values in repair materials under oblique and horizontal forces were observed in Group 1. The stress values ​​on repair materials gradually increased respectively starting from horizontal to vertical. As the elasticity modulus of the repair materials increased, the stress values ​​on root dentin increased. Through all force directions, except vertical forces, lower stress values were observed with FRC. The fracture resistance was bigger when using solely FRC or dual-cure resin cement in comparison to fiber-supported designs. Adding polyethylene fiber to re-restorations decreased stress values ​​compared to glass fiber addition. Therefore, when adding fibers, polyethylene fiber will be advantageous.

Resumo O objetivo foi avaliar o efeito da distribuição de estresse nas forças verticais, horizontais e oblíquas no modelo de dente após a recolocação dos fragmentos do incisivo superior com fratura radicular vertical (FRV) usando diferentes materiais, por meio da análise de elementos finitos (FEA) em 3D. Métodos: Foram projetados modelos de dentes com canal radicular, osso esponjoso e cortical. A FRV foi modelada em um dente com 4 modelos diferentes de reataque, como Grupo 1: cimento de cura dupla (DC) + compósito reforçado com fibra (FRC), Grupo 2: DC + fibra de polietileno, Grupo 3: DC + fibra de vidro e Grupo 4: DC. Foi aplicada uma força de 100 N em 3 direções diferentes. As tensões principais máximas (σmax) da dentina e os materiais de recolocação foram avaliados em imagens coloridas. Resultados: Os valores mais altos de σmax foram registrados nos materiais de reparo sob forças verticais para os Grupos 1 e 4, respectivamente; os Grupos 2 e 3 apresentaram semelhança. Os valores mais altos de σmax nos materiais de reparo sob forças horizontais e oblíquas foram observados no Grupo 3; no entanto, os valores mais baixos de σmax nos materiais de reparo sob forças oblíquas e horizontais foram observados no Grupo 1. Os valores de tensão nos materiais de reparo aumentaram gradualmente, respectivamente, começando da holizontal para a vertical. À medida que o módulo de elasticidade dos materiais de reparo aumentava, os valores de tensão na dentina da raiz aumentavam. Em todas as direções de força, exceto nas forças verticais, foram observados valores de tensão mais baixos com o FRC. Conclusões: a resistência à fratura foi maior quando se utilizou apenas FRC ou cimento resinoso de cura dupla em comparação com os designs com suporte de fibra. A adição de fibra de polietileno às restaurações diminuiu os valores de tensão em comparação com a adição de fibra de vidro. Portanto, ao adicionar fibras, a fibra de polietileno será vantajosa.

Surface treatments of the zirconia-reinforced lithium disilicate ceramic in the adhesion to the resin cement

Abstract This study verified the effect of surface treatments of the zirconia-reinforced lithium disilicate ceramic bonded to resin cement. Ceramic blocks were divided according to treatments (n=10): FA+SRX (Fluoric acid + silane RX), FA+MDP (Fluoric acid + MDP), FA+SCF+MDP (Fluoric acid + silane CF + MDP), FA+MEP (Fluoric acid + MEP), and MEP (Self-etch primer). Resin cement cylinders were made in the ceramic blocks, photoactivated with 1,200 mW/cm² for 40s, stored in water at 37°C for 24h, and evaluated by the microshear strength test, optical failure descriptive analysis (%), surface characterization (SEM) and contact angle (Goniometer). Other samples were submitted to 10,000 thermocycles between 5°C and 55°C. Bond strength data were submitted to two-way ANOVA and Tukey's test. Contact angle to one-way ANOVA and Games-Howell's test (5%). At 24h, MEP showed higher bond strength, and FA+SRX the lower. FA+MDP and FA+SCF+MDP showed similar values and FA+MEP was intermediate. After thermocycling, FA+SCF+MDP, FA+MEP, and MEP showed higher values, and FA+SRX the lower while FA+MDP was intermediate. When the periods were compared, FA+MDP, FA+SCF+MDP, FA+MEP, and MEP showed higher values for 24h while FA+SRX was similar. SEM showed retentive surface and crystal exposure when treated with FA+SCF+MDP. The less retentive surface was obtained with MEP, and the other treatments promoted intermediate irregularities. In conclusion, surface treatment and thermocycling promoted different values of adhesive strength and contact angle in a zirconia-reinforced lithium silicate ceramic. Failures were predominantly adhesive, and the ceramic surface was characterized by different levels of roughness and selective exposure of crystals.

Resumo O objetivo neste estudo foi verificar o efeito de tratamentos de superfície da cerâmica de dissilicato de lítio reforçada com zircônia fixada ao cimento resinoso. Os blocos cerâmicos foram separados de acordo com os tratamentos (n=10): AF+SRX (ácido fluorídrico + silano), AF+MDP (ácido fluorídrico + MDP), AF+SCF+MDP (ácido fluorídrico + silano + MDP), AF+MEP (Ácido fluorídrico + MEP) e MEP (Primer auto condicionante). Cilindros de cimento resinoso foram confeccionados em cada bloco cerâmico, foto ativados com 1.200 mW/cm² por 40 segundos, armazenados em água a 37°C por 24 horas e avaliados pelo teste de resistência ao micro cisalhamento, falha por análise descritiva em microscopia óptica (%), caracterização da superfície por imagens MEV e ângulo de contato (Goniômetro). Outras amostras foram submetidas a 10.000 ciclos térmicos (5° e 55°C). Os dados de resistência de união foram submetidos a ANOVA dois fatores e teste de Tukey (5%). Ângulo de contato com ANOVA um fator e teste de Games-Howell (5%). Em 24 horas, MEP apresentou maior resistência de união e AF+S a menor. AF+MDP e AF+SCF+MDP apresentaram valores similares e AF+MEP foi intermediário. Após a ciclagem térmica, AF+SCF+MDP, AF+MEP e MEP apresentaram valores maiores e AF+SRX o menor enquanto AF+MDP foi intermediário. Quando comparados os períodos, AF+MDP, AF+SCF+MDP, AF+MEP e MEP apresentaram valores maiores em 24 horas enquanto AF+SRX foi similar. MEV mostrou superfície mais retentiva e exposição de cristais quando tratada com AF+SCF+MDP. A superfície menos retentiva foi obtida com MEP, e os demais tratamentos promoveram irregularidades de superfície intermediárias. Conclui-se que o tratamento superficial e a termociclagem promoveram diferentes valores de resistência adesiva e ângulo de contato em cerâmica de silicato de lítio reforçada com zircônia. As falhas foram predominantemente adesivas, e a superfície cerâmica foi caracterizada com diferentes níveis de rugosidade e exposição seletiva de cristais.

Impact of Access Cavity Design on Fracture Resistance of Endodontically Treated Maxillary First Premolar: In Vitro

Abstract This study was designed to investigate the impact of access cavity designs on fracture resistance of endodontically treated maxillary first premolars. The study sample consisted of 72 intact maxillary first premolars, randomly divided into six groups (n = 12). A standardized proximal cavity preparation was prepared for all samples using standard bur. Groups I: control group with only standard proximal cavity and no endodontic access, group II: Truss access cavity, group III: Separated access to buccal and palatal canals without removal of dentine in between, group IV: Access to buccal and palatal canals with removal of dentine in between, group V: Traditional access cavity, group VI: Mesio-occlusal-distal cavity (MOD). For groups I and VI, only composite restoration was used to restore the proximal cavity, while for groups II- V, the access was prepared and endodontic treatment was performed on all teeth, then composite restoration was placed. The root canals were instrumented using nickel-titanium files, irrigated with sodium hypochlorite, and filled with AH plus sealer and gutta-percha using warm vertical condensation. All samples were then placed in an acrylic mold and underwent thermal aging for 10,000 cycles between 5 and 55°C. The samples were fixed in a universal testing machine with the long axis of the roots positioned at 20° to a load applied at a crosshead speed of 1 mm/min using a stainless steel semi-spherical indenter (Ø = 3 mm) until fracture occurred to determine the fracture resistance force in Newton. The normality test (Shapiro-Wilk) showed that data are normally distributed. Group II exhibited the highest mean fracture resistance, and group VI was the least likely to resist the fracture. No statistically significant differences between tested groups (p-value = 0.237). The MOD group showed a more unfavorable mode of fracture compared to other groups. No significant difference in fracture resistance between conservative and traditional access cavities. The missing marginal ridges, such as in MOD cavities played an important role in decreasing the fracture resistance of endodontically treated teeth.

Resumo O objetivo deste estudo foi investigar o impacto do design da cavidade de acesso na resistência à fratura de primeiros pré-molares superiores tratados endodonticamente. MÉTODOS: A amostra do estudo consistiu em 72 primeiros pré-molares superiores intactos, divididos aleatoriamente em seis grupos (n = 12). Um preparo padronizado da cavidade proximal foi realizado para todas as amostras usando broca padrão. Grupos I: grupo de controle com apenas cavidade proximal padrão e sem acesso endodôntico, grupo II: cavidade de acesso Truss, grupo III: acesso separado aos canais vestibular e palatino sem remoção de dentina entre eles, grupo IV: acesso aos canais vestibular e palatino com remoção de dentina entre eles, grupo V: cavidade de acesso tradicional, grupo VI: cavidade mesio-oclusal-distal (MOD). Para os grupos I e VI, apenas a restauração de compósito foi usada para restaurar a cavidade proximal. Já nos grupos II e V, o acesso foi preparado e o tratamento endodôntico foi realizado em todos os dentes e, em seguida, foi colocada a restauração de resina composta. Os canais radiculares foram instrumentados com limas de níquel-titânio, irrigados com hipoclorito de sódio e preenchidos com AH plus sealer e guta-percha usando condensação vertical quente. Todas as amostras foram então colocadas em molde de acrílico e submetidas a envelhecimento térmico por 10.000 ciclos entre 5 e 55°C. As amostras foram fixadas em uma máquina de teste universal com o eixo longo das raízes posicionado a 20° para uma carga aplicada a uma velocidade de cruzeta de 1 mm/min usando indentador semiesférico de aço inoxidável (Ø = 3 mm) até que ocorresse a fratura para determinar a força de resistência à fratura em Newton. RESULTADOS: O teste de normalidade (Shapiro-Wilk) mostrou que os dados são normalmente distribuídos. O grupo II apresentou a maior resistência média à fratura, e o grupo VI foi o menos propenso a resistir à fratura. Não houve diferenças estatisticamente significativas entre os grupos testados (p-valor = 0,237). O grupo MOD apresentou um modo de fratura mais desfavorável em comparação com os outros grupos. CONCLUSÕES: Não houve diferença significativa na resistência à fratura entre as cavidades de acesso conservador e tradicional. A ausência de cristas marginais, como nas cavidades MOD, desempenhou um papel importante na diminuição da resistência à fratura dos dentes tratados endodonticamente.

Microtensile bond strength of resin cements to 3-D printed and milled temporary restorative resins / Resistencia de unión en microtracción de cementos resinosos a resinas para provisionales impresas y fresadas

Abstract To evaluate the microtensile bond strength (µTBS) of two resin cements to 3D printed and milled CAD/CAM resins used for provisional fixed partial dentures. Blocks (5 x 5 x 5 mm) of three 3D-printed resins (Cosmos3DTemp / Yller; Resilab3D Temp / Wilcos and SmartPrint BioTemp, / MMTech) were printed (Photon, Anycubic Technology Co.). A milled material (VitaCAD-Temp, VITA) was used as control. Half the specimens were sandblasted and the rest were untreated. Two blocks were bonded with the corresponding resin cement: PanaviaV5 (Kuraray Noritake) and RelyX Ultimate (3M Oral Care). After 24 hours, the bonded blocks were sectioned into 1 x 1 mm side sticks. Half the beams were tested for µTBS and the other half was thermocycled (5000 cycles, 30s dwell-time, 5s transfer time) before µTBS testing. A four way Generalized Linear Model (material*sandblasting*cement*aging) analysis was applied. VITA exhibited the lowest µTBS, regardless of the cement, sandblasting and thermocycling. Sandblasting significantly improved the µTBS of VIT, especially after aging, but did not improve the µTBS of 3D printed resins. Sandblasting was not beneficial for 3D printed resins, although is crucial for adhesive cementation of milled temporary resins. Airborne particle abrasion affects the integrity of 3D-printed resins, without producing a benefit on the microtensile bond strength of these materials. However, sandblasting is crucial to achieve a high bond strength on milled temporary resins.

Resumen Evaluar la resistencia adhesiva en microtracción (µTBS) de dos cementos resinosos a resinas CAD/CAM impresas y fresadas indicadas para restauraciones provisionales. Bloques (5 x 5 x 5mm) de tres resinas impresas (Cosmos3DTemp / Yller; Resilab3D Temp / Wilcos and SmartPrint BioTemp, / MMTech) y una resina fresada (VitaCAD-Temp, VITA) fueron fabricados. La mitad de los especímenes fueron arenados y el resto no recibió tratamiento mecánico. Dos bloques con condiciones de tratamiento iguales fueron cementados con cemento resinoso (PanaviaV5 / Kuraray Noritake y RelyX Ultimate / 3M Oral Care). Después de 24 horas los bloques fueron seccionados en palitos de 1 mm² de área. En la mitad de los especímenes se midió la TBS inmediatamente y el resto fue termociclado (5000 ciclos, 30s remojo, 5s transferencia) antes de la prueba de TBS. Se aplica un análisis estadístico por Modelo Linear General con 4 factores (material*arenado*cemento*termociclado). La resina VITA presentó la menor µTBS, independientemente del cemento usado, el arenado y el termociclado. Sin embargo, el arenado aumentó la µTBS de VIT, especialmente después del termociclado. Por otro lado, el arenado no resultó en un aumento significativo de la µTBS de las resinas impresas. El arenado no fue beneficiosos para las resinas impresas, aunque es un paso crucial para la cementación adhesive de las resinas fresadas. El arenado afecta la integridad de las capas de las resinas impresas, sin generar un beneficio en la TBS.

Os Fenômenos de Massa e as Redes Sociais no Contexto Político Brasileiro: Uma Leitura Psicanalítica / Mass Phenomena and Social Networks in the Brazilian Political Context: A Psychoanalytic Reading / Fenómenos de Masas y Redes Sociales en el Contexto Político Brasileño: Una Lectura Psicoanalítica

O presente artigo tem como objetivo analisar os movimentos de massa contemporâneos presentes no cenário político brasileiro nos anos de 2013 e 2015, assim como seus efeitos no laço social, a partir das contribuições da psicanálise, valendo-se, em especial, dos textos clássicos de Freud que tratam sobre as massas e o mal-estar na cultura e das elaborações lacanianas sobre os discursos que sustentam o laço social. Com isso, busca-se levantar algumas hipóteses e refletir acerca do fenômeno de formação de massas na atualidade, onde se destaca a mais potente ferramenta de mobilização política contemporânea: as redes sociais. Atualmente, avolumam-se os exemplos no Brasil e no mundo de manifestações convocadas pelas redes sociais, com seu poder de propagação e disseminação de informação e desinformação. Nos últimos dez anos, o que colhemos é a intensificação e complexificação desses processos, conforme avança o "poder" das redes sociais e a forma como ela vem se estabelecendo em nossas sociedades. Na copulação entre ciência e capitalismo observada nas redes, os algoritmos respondem e operam de acordo com os interesses do mercado, manipulando as subjetividades.

This article aims to analyze the contemporary mass movements present on the Brazilian political scenario in the years 2013 and 2015, as well as their effects on the social bond, based on the contributions of psychoanalysis, using, in particular, Freud's classic texts that deal with the masses, civilization and its discontents and the lacanian elaborations on the discourses that sustain the social bond. With this, we seek to raise some hypotheses and reflect on the phenomenon of mass formation today, where the most powerful tool of contemporary political mobilization stands out: the social networks. Currently, examples in Brazil and around the world of demonstrations convened by social networks, with their power to propagate and disseminate information and misinformation, are growing. In the last ten years, what we have seen is the intensification and complexity of these processes, as the "power" of social networks advances and the way in which it has been establishing itself in our societies. In the copulation between science and capitalism observed in the networks, the algorithms respond and operate according to the interests of the market, manipulating subjectivities.

Este artículo tiene como objetivo analizar los movimientos de masas contemporáneos presentes en el escenario político brasileño en los años 2013 y 2015, así como sus efectos en el lazo social, a partir de las contribuciones del psicoanálisis, utilizando, en particular, de los textos clásicos de Freud que tratan sobre las masas y el malestar en la cultura y las elaboraciones lacanianas sobre los discursos que sustentan el lazo social. Con ello, buscamos plantear algunas hipótesis y reflexionar sobre el fenómeno de la formación de masas en la actualidad, donde se destaca la herramienta más poderosa de la movilización política contemporánea: las redes sociales. Actualmente, crecen los ejemplos en Brasil y en el mundo de manifestaciones convocadas por las redes sociales, con su poder de propagar y difundir información y desinformación. En los últimos diez años lo que hemos visto es la intensificación y complejidad de estos procesos, a medida que avanza el "poder" de las redes sociales y la forma en que se ha ido instalando en nuestras sociedades. En la cópula entre ciencia y capitalismo observada en las redes, los algoritmos responden y operan de acuerdo a los intereses del mercado, manipulando subjetividades.

Fracture resistance and bonding performance after antioxidants pre-treatment in non-vital and bleached teeth

Abstract This study aimed to evaluate the effect of antioxidant solutions on fracture strength and bonding performance in non-vital and bleached (38% hydrogen peroxide) teeth. One hundred and eighty dentin specimens were obtained, 60 for each test: fracture strength, hybrid layer thickness, and bond strength. The groups (n=10) were randomly composed according to post-bleaching protocol: REST - restoration, without bleaching; BL - bleaching + restoration; SA - bleaching, 10% sodium ascorbate solution, and restoration; AT - bleaching, 10% α-tocopherol solution, and restoration; CRAN - bleaching, 5% cranberry solution, and restoration; CAP - bleaching, 0.0025% capsaicin solution, and restoration. Data were analyzed with ANOVA, Kruskal-Wallis, Dunn, and Qui-Square tests (α=0.05). The highest fracture strength values were observed in REST (1508.96 ±148.15 N), without significant difference for the bleached groups (p>0.05), regardless of the antioxidant use. The hybrid layer thickness in the group that was not subjected to bleaching (REST) was significantly higher than in any other group. The bond strength in the bleached and antioxidants-treated groups (SA, AT, CRAN, CAP) has no differences with the bleached group without antioxidants (BL). Adhesive failures were predominant in the groups that did not receive the antioxidant application. In conclusion, the evaluated antioxidants did not show an effect on the fracture strength, hybrid layer thickness, or bond strength of dentin bleached after endodontic treatment. The application of 10% sodium ascorbate, 10% alpha-tocopherol, 5% cranberry, or 0.0025% capsaicin solutions is not an effective step and should not be considered for the restorative protocols after non-vital bleaching.

Resumo Este estudo teve como objetivo avaliar o efeito de soluções antioxidantes na resistência à fratura e resistência de união em dentes tratados endodonticamente e clareados (38% de peróxido de hidrogênio). Cento e oitenta espécimes de dentina foram obtidos, 60 para cada teste: resistência à fratura, espessura da camada híbrida e resistência de união. Os grupos (n=10) foram compostos aleatoriamente de acordo com o protocolo pós-clareamento: REST - restauração, sem clareamento; BL - clareamento + restauração; SA - clareamento, solução de ascorbato de sódio a 10% e restauração; AT - clareamento, solução de α-tocoferol a 10% e restauração; CRAN - clareamento, solução de cranberry a 5% e restauração; CAP - clareamento, solução de capsaicina 0,0025% e restauração. Os dados foram analisados ​​com os testes ANOVA, Kruskal-Wallis, Dunn e Qui-Quadrado (α=0,05). Os maiores valores de resistência à fratura foram observados em REST (1508,96 ±148,15 N), sem diferença significativa para os grupos clareados (p>0,05), independente do uso de antioxidantes. A espessura da camada híbrida no grupo que não foi submetido ao clareamento (REST) foi significativamente maior do que em qualquer outro grupo. A resistência de união nos grupos clareado e tratado com antioxidantes (SA, AT, CRAN, CAP) não apresentou diferenças com o grupo branqueado sem antioxidantes (BL). As falhas adesivas foram predominantes nos grupos que não receberam a aplicação do antioxidante. Em conclusão, os antioxidantes avaliados não mostraram efeito sobre a resistência à fratura, espessura da camada híbrida ou resistência de união à dentina clareada após tratamento endodôntico. A aplicação de soluções de ascorbato de sódio 10%, alfa-tocoferol 10%, cranberry 5% ou capsaicina 0,0025% não é uma etapa eficaz e não deve ser considerada para os protocolos restauradores após clareamento não vital.

Sustentabilidade afetiva nos atendimentos do CREAS: as percepções das famílias / Affective support in the service of CREAS: the perceptions of families / Sostenibilidad afectiva en los servicios del CREAS: las percepciones de las familias

A Política de Assistência Social mantém a centralidade de suas intervenções na instituição familiar a fim de fortalecer a garantia de direitos à população em situação de desproteção social. Atento a esse cenário, o objetivo desta pesquisa consistiu em analisar a percepção das famílias sobre as intervenções realizadas pelos psicólogos em um Centro de Referência Especializado de Assistência Social (CREAS) situado em uma cidade do interior do estado do Paraná. Adotando uma perspectiva qualitativa, os seis participantes relataram a experiência desses atendimentos e seus impactos sobre a família. Como resultado, foi possível conhecer os receios e medos presentes nos primeiros contatos e como isso foi superado à medida que o vínculo afetivo era fortalecido, abrindo espaço para o relato das experiências difíceis de violência familiar. Ao final da pesquisa, foi possível compreender a relevância de construir uma sustentabilidade afetiva capaz de afirmar a vinculação e acolher as famílias. (AU)

Social Assistance Policy maintains the centrality of its interventions in the family institution in order to strengthen the guarantee of rights to the population in a situation of social unprotect. Aware of this scenario, the objective of this research was to analyze the perception of families on the interventions carried out by psychologists at a Specialized Social Assistance Reference Center (CREAS) located in a city in the interior of the state of Paraná. Adopting a qualitative perspective, the six participants reported the experience of these services and their impacts on the family. As a result, it was possible to know the fears and dreads present in the first contacts and how this was overcome as the affective bond was strengthened, opening space for reporting difficult family violence experiences. At the end of the research, it was possible to understand the relevance of building an affective sustainability capable of affirming the link and welcoming the families. (AU)

La Política de Asistencia Social mantiene la centralidad de sus intervenciones en la institución familiar para fortalecer la garantía de derechos a la población en situación de desprotección social. Conscientes de este escenario, el objetivo de esta investigación fue analizar la percepción de las familias sobre las intervenciones realizadas por psicólogos en un Centro de Referencia Especializado en Asistencia Social (CREAS) ubicado en una ciudad del interior del estado de Paraná. Adoptando una perspectiva cualitativa, los seis participantes relataron la experiencia de estos servicios y sus impactos en la familia. Como resultado, fue posible conocer los miedos y ansiedades presentes en los primeros contactos y cómo éstos fueron superados a medida que el vínculo afectivo se reforzó, abriendo un espacio para la denuncia de experiencias difíciles de violencia familiar. Al final de la investigación, se pudo comprender la relevancia de construir una sostenibilidad afectiva capaz de afirmar el vínculo y acoger a las familias. (AU)

Entre encontros faltosos e excessivos: laços amorosos e uso de tecnologias para pensar o sujeito / Between missing and excessive meetings: love bows and the use of technologies to think about the subject / Entre rencontres manquantes et excessives: liens amoureux et utilisation des technologies pour réfléchir au sujet

A cada dia, o mundo tem se virtualizado mais. Não só estabelecemos laços por intermédio da virtualidade, mas tentamos também estabelecer laços com esses pequenos objetos da tecnociência: os gadgets. Partindo disso, este artigo tem como objetivo explorar o laço social que há entre os sujeitos e seus objetos de consumo, como podemos perceber no filme her, no qual um homem se apaixona pela voz de um sistema operacional. Para tanto, utilizamos a teoria dos discursos de Lacan, que nos ajudou a trabalhar questões do sujeito e do laço social a partir do uso da tecnologia e reconhecendo nela algo do sujeito e também do laço, bem como pensar seus limites e possibilidades aí postos.

Each day, the world has been more virtualized. We not only stablish bonds by virtuality, but we also try to stablish bonds with these small techno science's objects: the gadgets. Based on this, this article aims to explore the social bond that there is between the subjects and their consumption objects, as we can notice on her movie, in which a man falls in love for an operational system's voice. To do so, we use Lacan's speeches theory which helped us to work on the subject's questions and the social bond from the use of technology and recognizing in it something from the subject and the bond itself, as well as think about its limits and possibilities at this point.

Chaque jour, le monde est devenu plus virtualisé. Non seulement nous établissons des liens grâce à la virtualité, mais nous essayons également d'établir des liens avec ces petits objets de la technoscience: les gadgets. Partant de là, cet article vise à explorer le lien social qui existe entre les sujets et leurs objets de consommation, comme on peut le voir dans le film her, dans lequel un homme tombe amoureux de la voix d'un système d'exploitation. Pour ce faire, nous avons utilisé la théorie des discours de Lacan qui nous a aidés à travailler sur les questions du sujet et du lien social à partir de l'utilisation de la technologie et à y reconnaître quelque chose du sujet et aussi du lien, ainsi qu'à réfléchir à ses limites et possibilités.

Effect of sodium/calcium hypochlorite on adhesion and adaptation of fiber posts luted with a dual resin cement

Abstract This study aimed to evaluate the effect of different concentrations of sodium hypochlorite (NaOCl) and calcium hypochlorite [Ca(OCl)2] on the bond strength and adaptation of glass fiber posts luted with a dual-curing resin cement. Fifty decoronated premolars were sectioned 14 mm from the apex and endodontically treated. The root canal filling was partially removed. The specimens were divided into 5 groups (n=10) according to the irrigant for post space irrigation: 0.9% sodium chloride (NaCl), (control); 2.5% NaOCl; 5.25% NaOCl; 2.5% Ca(OCl)2; and 5.25% Ca(OCl)2. For each group, irrigation was performed with 5 ml of solution. Afterward, the posts were luted with a dual-curing resin cement. One slice from each third was obtained and submitted to the push-out test and failure modes analysis. An additional slice from the middle third was submitted to confocal images for analysis of adaptation failures (gaps). Two-way ANOVA, Tukey's post-hoc, Kruskal-Wallis with Bonferroni adjusted, and chi-square tests, analyzed data. The group treated with 5.25% NaOCl showed lower bond strength values and generated more cohesive failures compared to the control (p < 0.05). Bond strength decreased from coronal to apical in the post space (p < 0.001). The groups treated with NaOCl had the highest percentages of gaps compared to the control (p < 0.05). Regardless of concentration, Ca(OCl)2 did not influence the bond strength and the occurrence of gaps (P > 0.05). Ca(OCl)2 is a good option for irrigating the post space before luting a fiber post with a dual-curing resin cement.

Resumo Este estudo teve como objetivo avaliar o efeito de diferentes concentrações de hipoclorito de sódio (NaOCl) e hipoclorito de cálcio [Ca(OCl)2] na resistência de união e adaptação de pinos de fibra de vidro cimentados com um cimento resinoso dual. Cinquenta pré-molares tiveram suas coroas removidas, foram seccionados a 14 mm do ápice e tratados endodonticamente. A obturação do canal radicular foi parcialmente removida. Os espécimes foram divididos em 5 grupos (n=10) de acordo com o irrigante para irrigação do espaço do pino: cloreto de sódio 0.9% (NaCl), (controle); NaOCl 2.5%; NaOCl 5.25%; Ca(OCl)2 2.5%; e Ca(OCl)2 5.25%. Para cada grupo, a irrigação foi realizada com 5 ml da solução. Posteriormente, os pinos foram cimentados com um cimento resinoso dual. Uma fatia de cada terço foi obtida e submetida ao teste push-out e análise dos modos de falha. Um corte adicional do terço médio foi submetido a imagens confocais para análise de falhas de adaptação (gaps). Os dados foram analisados pelos testes ANOVA de duas vias, post-hoc de Tukey, Kruskal-Wallis com ajuste de Bonferroni e qui-quadrado. O grupo tratado com NaOCl 5.25% apresentou menores valores de resistência de união e gerou mais falhas coesivas em relação ao controle (p < 0.05). A resistência de união diminuiu de coronal para apical no espaço do pino (p < 0.001). Os grupos tratados com NaOCl apresentaram os maiores percentuais de gaps em relação ao controle (p < 0.05). Independentemente da concentração, o Ca(OCl)2 não influenciou a resistência de união e a ocorrência de gaps (P > 0.05). O Ca(OCl)2 é uma boa opção para irrigar o espaço do pino antes de cimentar um pino de fibra com um cimento resinoso dual.

Influence of different surface treatments on bond strength of a Self-Adhesive resin cement to CAD-CAM materials / Influencia de los diferentes tratamientos superficiales en la unión del cemento resinoso autoadhesivo a los materiales CAD-CAM

To evaluate the shear bond strength (SBS) of self-adhesive resin cement when used with two different computer-aided design (CAD)-computer-aided manufacturing (CAM) materials after various surface treatments. Nanoceramic resin Lava Ultimate (LU) and feldspathic ceramic Vita Mark II (VM) CAD-CAM block samples were prepared with 1.5-mm thickness, and a total of 90 samples were obtained (N=90), with five samples of each block. The samples were divided into the following five groups according to the surface treatments (n=9): group 1, untreated (control); group 2,5% hydrofluoric acid etching; group 3, Er: YAG laser irradiation; group 4, tribochemical silica coating (Cojet); and group 5, air-abrasion with Al2O3. After silane application, resin cement was applied on a transparent matrix (diameter, 3mm; height, 2mm) on the blocks. SBS was determined using a universal testing device at a crosshead speed of 1mm/min. Two-way analysis of variance (ANOVA) and Tukey's post hoc tests were used to analyze the SBS values. LU showed the highest SBS value in group 4. The average SBS values in groups 3 and were found to be lower than that in the control group (p<0.05). When VM was examined, while all surface treatments increased the SBS values significantly, the highest SBS value was observed in group 4 (p<0.05). This study revealed that all surface treatments used negatively affected the bond strength values of self-adhesive resin cement to LU, except for Cojet application. The SBS values of resin cement with VM increased in all surface treatment application groups.

Evaluar la resistencia de unión al corte (SBS) del cemento de resina autoadhesivo cuando se utiliza con dos materiales diferentes de diseño asistido por computadora (CAD) y fabricación asistida por computadora (CAM) después de varios tratamientos superficiales. Se prepararon muestras de bloques CAD-CAM de resina Lava Ultimate (LU) y cerámica feldespática Vita Mark II (VM) con un espesor de 1,5mm, y se obtuvieron un total de 90 muestras (N=90), con cinco muestras de cada bloque. Las muestras se dividieron en los siguientes cinco grupos según los tratamientos superficiales (n=9): grupo 1, sin tratar (control); grupo 2, grabado con ácido fluorhídrico al 5%; grupo 3, irradiación con láser Er: YAG; grupo 4, recubrimiento triboquímico de sílice (Cojet); y grupo 5, aire-abrasión con Al2O3. Después de la aplicación de silano, se aplicó cemento de resina sobre una matriz transparente (diámetro, 3mm; altura, 2mm) sobre los bloques. La SBS se determinó usando un dispositivo de prueba universal a una velocidad de cruceta de 1mm/min. Se utilizaron análisis de varianza bidireccional (ANOVA) y pruebas post hoc de Tukey para analizar los valores de SBS. LU mostró el valor más alto de SBS en el grupo 4. Los valores promedio de SBS en los grupos 3 y fueron más bajos que en el grupo de control (p<0,05). Cuando se examinó VM, mientras que todos los tratamientos superficiales aumentaron significativamente los valores de SBS, el valor más alto de SBS se observó en el grupo 4 (p<0,05). Este estudio reveló que todos los tratamientos de superficie utilizados afectaron negativamente los valores de resistencia de la unión del cemento de resina autoadhesivo a LU, a excepción de la aplicación Cojet. Los valores de SBS del cemento de resina con VM aumentaron en todos los grupos de aplicación de tratamiento de superficie.

Um traço e um abraço: Afetividade como elemento facilitador da aprendizagem / A trace and a hug: Affectivity as a facilitating element of learning

A afetividade fecunda o ser humano por toda a sua existência, desde o nascimento até a sua morte, estando presente em todas as fases da vida. A questão que se coloca é: Qual a importância da afetividade na relação aluno e professor e como esta influencia a prática pedagógica? Diversos estudos, de abordagem freudiana, piagetiana, vygotskyana e walloniana, dão ênfase à relação da afetividade com o desenvolvimento cognitivo, tendo, portanto, relação com a aprendizagem. A afetividade indiscutivelmente ocupa lugar de destaque no processo de aprendizagem e a maneira como ela acontece pode ser decisiva na concepção de mundo construída pelo aluno, bem como na sua elaboração do conhecimento.

Affectivity supports the human being throughout its existence, from birth to death, being present in all stages of life. The question that arises is: What is the importance of affectivity in the student-teacher relationship and how does it influence pedagogical practice? Several studies, with a Freudian, Piagetian, Vygotskyan and Wallonian approach, emphasize the relationship between affectivity and cognitive development, thus having a relationship with learning. Affectivity undoubtedly occupies a prominent place within the learning process and the way in which it happens can be decisive in the conception of the world built by the student, as well as in their elaboration of knowledge.

ADMET, Pharmacokinetic and Docking properties of the fungal drug 2- (2, 4-difluorophenyl)-1, 3-bis (1, 2, 4-triazol-1-yl) propan-2-ol by using Quantum computational methods

The current study contributes to a better knowledge of the FCZ's characteristics and bioactivity. The ADMET properties have been calculated and the results have been illustrated; as a result, it has become quite popular for virtual pharmaceutical analysis. This research aims to examine FCZ’s optimized structure and properties by analyzing various computational calculations. Bond length, Bond angle, Mulliken charges have been analyzed for the studies. The experimental geometrical parameters and theoretical data were compared with ADME parameters, biomarker properties, pH value, drug like nature, Marvin sketch, Swiss ADME to quantify molecular descriptors just as to survey atomic elements. ADMET properties introduce the influence of the drug levels and its kinetics with the tissues of the body. It also explains about the metabolism, toxicity of the drugs when introduced to the system. The analysis on pharmacokinetic properties has helped a lot in the drug development for further studies. The target prediction of FCZ has been studied along with the docking study. Docking study is an important program in order to study about the binding of the small ligand into a receptor like proteins. This method is very useful in drug discovery which provides insights into various studies. This will help in further development of the drugs which will finally help the society in large scale. FCZ helps pharmaceutical industry in developing the drugs to treat chronic disease when combined with other molecules. Hence the present study is really helpful in drug designing and in the development of new drugs.

Effects of applying procyanidins on the bond strength of bleached dentin to composite resin / 口腔疾病防治

Objective@#To study the influence of procyanidins on the bonding strength of dentin bleached by carbamide peroxide to composite resin.@*Methods @#By applying different treatments to dentin bonding interfaces, 120 human third molars were randomly divided into 12 groups (n = 10): W group (no bleaching+deionized water), Wa group (no bleaching+deionized water+aging), WT1 group (no bleaching+5% procyanidins for 1 min), WT1a group (no bleaching+5% procyanidins for 1 min+aging), WT2 group (no bleaching+5% procyanidins for 5 min), WT2a group (no bleaching+5% procyanidins for 5 min+aging), C group (carbamide peroxide+deionized water), Ca group (carbamide peroxide+deionized water+aging), CT1 group (carbamide peroxide+5% procyanidins for 1 min), CT1a group (carbamide peroxide+5% procyanidins for 1 min+aging), CT2 group (carbamide peroxide+5% procyanidins for 5 min), and CT2a group (carbamide peroxide+5% procyanidins for 5 min+aging). The bond strength to composite resin was measured by universal mechanical testing machine, microstructure and the nanoleakages were measured by scanning electron microscope immediately or after the thermal cycling aging test.@*Results@#The immediate bond strength of the bleached groups pretreated with procyanidins for 1 min (P<0.001) and 5 min (P<0.001) was higher than that of Group C, and the difference was statistically significant. Meanwhile, there was no statistically significant difference between Group CT1 and Group CT2 (P = 1.000). After the thermal cycles, the bond strength of each group declined. The differences between Group W and Group Wa (P<0.001) and Group C and Group Ca (P<0.001) were statistically significant, but no significant differences between Group CT1 and Group CT1a (P = 0.052) or Group CT2 and Group CT2a (P = 0.053) were found. The main effects of “aging” (P<0.001), “bleaching” (P<0.001) and “procyanidins” (P<0.001) and the second-order interaction effects of “bleaching * procyanidins” (P = 0.008), “bleaching * aging” (P = 0.024), and “aging * procyanidins” (P<0.001) were statistically significant. SEM observations showed that the hybrid layers in Groups C, CT1 and CT2 were not clear, and the hybrid layers in Groups Ca, CT1a and CT2a were partially destroyed and disintegrated. Under backscattering mode, it was observed that there were a large number of silver nitrate particles in the hybrid layer of Group Ca, and the residual silver ions in the hybrid layer of Groups CT1a and CT2a were decreased. @*Conclusion@# Pretreatment with 5% procyanidins for 1 min can improve the immediate bond strength of dentin bleached by carbamide peroxide to composite resin and maintain bonding durability.

Design and synthesis of peptide-drug conjugates and fluorescent probe based on α-conotoxin ArIBV11L,V16D / 药学学报

italic>α-Conotoxin ArIB[V11L,V16D] is currently the most optimal selective inhibitor of α7 nicotinic acetylcholine receptor (nAChR) known. In order to explore chemical modification methods and enrich its application in targeting nAChR, this study utilized the linker to covalently connect camptothecin and 7-amino-4-methylcoumarin to the [2,4] disulfide bond of ArIB[V11L,V16D]. Therefore, two peptide-drug conjugates (PDCs), ArIB[V11L,V16D]-5 and ArIB[V11L,V16D]-6, and one fluorescent-labeled peptide, ArIB[V11L,V16D]-7 were constructed. Cytotoxicity evaluation showed that the IC50 values against non-small cell lung cancer cell line A549 of the two PDCs were respectively 1.3 and 4.1 times of camptothecin, indicating slight reduction in activity at the cellular level which was related to the linker structure. Fluorescence spectrum scanning revealed that the excitation and emission wavelength of the fluorescent-labeled peptide were 340 nm and 403 nm respectively, and the fluorescence features of 7-amino-4-methylcoumarin as a marker were retained without fluorescence quenching. This modification strategy laid a solid foundation for the further application of α-conotoxin ArIB[V11L,V16D] in PDCs and fluorescent probes.

An animal research on the application of drag-and-bond anastomosis in the anastomosis between bladder and intestine / 中华泌尿外科杂志

Objective:To explore the feasibility of anastomosis between bladder and intestine of experimental rabbit by drag anastomosis.Methods:In this study 40 Japanese big-eared rabbits were randomly divided into two groups through random number table, the experimental group and the control group, each group with 20 rabbits. In the experimental group, the bladder neck was fixed to the catheter and then the catheter was drawn outward. With the traction of the catheter, the bladder neck was anastomosed with the distal intestinal tube by means of suture free. The control group was anastomosed by regular interrupted suture of bladder and intestine. The operation time, anastomosis time, intraoperative blood loss, postoperative urinary leakage rate and postoperative anastomotic healing of rabbits in the two groups were compared.Results:The operation time of the experimental group was shorter than that of the traditional interrupted suture anastomosis group [(33.26±2.79)min vs. (35.25±1.83)min, P=0.014]. The anastomosis time of the experimental group was significantly shorter than that of the traditional interrupted suture anastomosis group[(7.55±1.2)min vs. (8.65±1.03 min), P=0.005]. The intraoperative blood loss in the experimental group was similar to that in the control group[(6.47±2.41) ml vs. (6.75±1.83) ml, P=0.691]. The event of contrast media extravasation occurred in 2 of the 10 experimental rabbits after receiving cystography in the experimental group, and the urinary leakage rate was 20%(2/10). In the control group, contrast media extravasation occurred in 1 of the 9 experimental rabbits after receiving cystography, and the urinary leakage rate was 11.1%(1/9), and the difference of the two groups was not statistically significant ( P=0.348). Anastomotic healing score was (2.0±0.7) in the experimental group, and (2.1±0.74) in the control group ( P=0.767). Conclusions:The bladder-intestine drag-and-bond anastomosis technique, with significantly shorter anastomosis time, was feasible, easy and convenient. Our research provides an experimental and theoretical basis for the clinical application of drag-and-bond anastomosis technique in clinic.

Expression, thermal stability modification and application in PHB degradation of polyhydroxyalkanoate depolymerase from Thermomonospora umbrina / 生物工程学报

Polyhydroxyalkanoate depolymerase (PHAD) can be used for the degradation and recovery of polyhydroxyalkanoate (PHA). In order to develop a PHAD with good stability under high temperature, PHAD from Thermomonospora umbrina (TumPHAD) was heterelogously expressed in Escherichia coli BL21(DE3). At the same time, a mutant A190C/V240C with enhanced stability was obtained via rational design of disulfide bonds. Characterization of enzymatic properties showed that the mutant A190C/V240C had an optimum temperature of 60 ℃, which was 20 ℃ higher than that of the wild type. The half-life at 50 ℃ was 7 hours, at 50 ℃ which was 21 times longer than that of the wild type. The mutant A190C/V240C was used for the degradation of polyhydroxybutyrate (PHB), one of the typical PHA. At 50 ℃, the degradation rate of PHB being treated for 2 hours and 12 hours was 2.1 times and 3.8 times higher than that of the wild type, respectively. The TumPHAD mutant A190C/V240C obtained in this study shows tolerance to high temperature resistance, good thermal stability and strong PHB degradation ability, which may facilitate the degradation and recovery of PHB.

Association of pre school children physical activities and sedentary behaviors on calcanues bone density / 中国学校卫生

Objective@#To investigate the effects of physical activity (PA) intensity and sedentary behavior (SB) on calcanues bone mineral density (BMD) in preschool children, so as to provide a basis for rationalizing the daily physical activity of preschool children to promote bone health.@*Methods@#A total of 673 pre school children aged 3-6 years from nine kindergartens in Pingxiang City, Ganzhou City and Yingtan City of Jiangxi Province, were selected from September to December 2021 by using the whole stratified cluster random sampling method. The PA levels and SB were measured by using a three axis acceleration sensor, and left calcanues BMD was measured by an ultrasound bone densitometer. Multiple linear regression was used to explore the effects of changes in PA on calcanues BMD in pre school children of all ages.@*Results@#Of the 673 preschoolers surveyed, 498 (74.0%) achieved an average of ≥60 min of moderate to vigorous physical activity (MVPA) per day, there were 265 boys (71.2%), and 233 girls ( 77.4 %). The difference between genders was not statistically significant ( χ 2=2.77, P >0.05). There was no statistically significant difference in the BMD test of the calcaneus bones of preschoolers by gender ( Z=0.42, P >0.05). The difference in BMD results of pre school children with 3, 4, 5 to 6 years was statistically significant ( H=2.65, P <0.05). Correlation analysis revealed a negative correlation between SB duration and calcaneus BMD ( r =-0.13), and a positive correlation between low intensity physical activity (LPA) duration, MVPA duration, and calcaneus BMD ( r =0.14, 0.25 ) ( P <0.05). Multivariate linear regression analysis showed that SB duration negatively correlated with calcaneus BMD, whereas LPA and MVPA duration positively correlated with calcaneus BMD ( P <0.05).@*Conclusions@#MVPA duration is positively correlated with the growth of BMD in the heel bone and negatively correlated with SB. The kindergartens can adjust their curricula according to the physical and mental developmental characteristics, gender and age differences of pre school children, increase the time of outdoor activities, and reduce the sedentary time to promote the bone health of young children.