Influence of the addition of nanohydroxyapatite to scaffolds on proliferation and differentiation of human mesenchymal stem cells: a systematic review of in vitro studies

One of the main challenges of tissue engineering in dentistry is to replace bone and dental tissues with strategies or techniques that simulate physiological tissue repair conditions. This systematic review of in vitro studies aimed to evaluate the influence of the addition of nanohydroxyapatite (NHap) to scaffolds on cell proliferation and osteogenic and odontogenic differentiation of human mesenchymal stem cells. In vitro studies on human stem cells that proliferated and differentiated into odontogenic and osteogenic cells in scaffolds containing NHap were included in this study. Searches in PubMed/MEDLINE, Scopus, Web of Science, OpenGrey, ProQuest, and Cochrane Library electronic databases were performed. The total of 333 articles was found across all databases. After reading and analyzing titles and abstracts, 8 articles were selected for full reading and extraction of qualitative data. Results showed that despite the large variability in scaffold composition, NHap-containing scaffolds promoted high rates of cell proliferation, increased alkaline phosphatase (ALP) activity during short culture periods, and induced differentiation, as evidenced by the high expression of genes involved in osteogenesis and odontogenesis. However, further studies with greater standardization regarding NHap concentration, type of scaffolds, and evaluation period are needed to observe possible interference of these criteria in the action of NHap on the proliferation and differentiation of human stem cells.

Influence of working length and anatomical complexities on the apical root canal filling: a nano-CT study

Abstract The present study aimed to compare the filled volume by gutta-percha and sealer in the apical region of the main canal and ramifications, after instrumentation at two different working lengths using nano-computed tomography (nano-CT). Twenty-two premolars with apical ramifications were selected after micro-computed tomography evaluation and were randomly divided into groups for further endodontic instrumentation at two different working lengths: G1 - Root canals shaped 1 mm short of the apical foramen (n=11), and G2 - Root canals shaped at the apical foramen (n=11). After completing root treatment, nano-CT images were acquired, and the filled volume by gutta-percha and sealer in the main canal apical 0-4 mm and 0-1 mm ranges, and apical ramifications were objectively measured by an operator specialized in both radiology and endodontics, blinded for both groups. The Mann-Whitney test was applied to compare both groups regarding the filling of the main canal apical ranges and apical ramifications with a significance level of 5% (α ≤ 0.05). It was observed that root canals shaped at the apical foramen had a larger volume of the main canal filled than root canals shaped 1 mm short of the apical foramen, at both apical ranges (0-4 and 0-1 mm) (p<0.05). Regarding the filling of the apical ramifications, there was no significant difference between groups (p>0.05). In conclusion, the root canals shaped at apical foramen exhibited increased filling volume of the main canal in the apical region. However, neither of both working lengths influenced filling of the apical ramifications.

Resumo O presente estudo teve como objetivo comparar o volume preenchido por guta-percha e cimento na região apical do canal principal e ramificações, após instrumentação em dois comprimentos de trabalho diferentes, por meio de nano tomografia computadorizada (nano-TC). Vinte e dois pré-molares com ramificações apicais foram selecionados após avaliação por micro-tomografia computadorizada e foram divididos aleatoriamente em grupos para posterior instrumentação endodôntica em dois comprimentos de trabalho diferentes: G1 - Canais radiculares instrumentados 1 mm aquém do forame apical (n = 11) e G2 - Canais radiculares instrumentados até o forame apical (n = 11). Após a obturação dos canais radiculares, imagens de nano-CT foram adquiridas, e o volume preenchido por guta-percha e cimento nas faixas apicais de 0-4 mm e 0-1 mm do canal principal, e ramificações apicais, foram avaliadas objetivamente por um especialista em radiologia e endodontia, cego para ambos os grupos. O teste de Mann-Whitney foi aplicado para comparar os dois grupos quanto ao preenchimento das faixas apicais do canal principal e ramificações com nível de significância de 5% (α ≤ 0,05). Observou-se que canais radiculares instrumentados até o forame apical apresentaram maior volume do canal principal preenchido do que canais radiculares instrumentados 1 mm aquém do forame apical, em ambas as faixas apicais (0-4 e 0-1 mm) (p <0,05) Em relação ao preenchimento das ramificações apicais, não houve diferença significativa entre os grupos (p> 0,05). Em conclusão, os canais radiculares instrumentados até o forame apical mostraram um maior volume de preenchimento na região apical do canal principal. No entanto, os dois diferentes comprimentos de trabalho não influenciaram o preenchimento das ramificações apicais.

Challenges in the use of nanostructures as carriers of nucleic acids in clinical practice

ABSTRACT The delivery of nucleic acids to cells is considered a crucial step for the success of genetic modifications aimed at therapeutic purposes or production of genetically modified animals. In this context, nanotechnology is one of the most promising fields of science, with the potential to solve several existing problems. Nanostructures have desirable characteristics to be used as carriers, such as nanometric size, large surface area, cell internalization capacity, prolonged and controlled release, among others. Genetically modified animals can contribute to the production of biopharmaceuticals, through the expression of high-associated-value molecules. The production of these animals, also known as biofactories, further enhances Brazilian agribusiness, since it allows adding value to the final product, and favors the integration between the agricultural market and the pharmaceutical sector. However, there is a growing concern about the safety and possible harmful effects of nanostructures, since data on the safe use of these materials are still insufficient. The objective of this review was to address aspects of the use of nanostructures, mainly carbon nanotubes as nucleic acid carriers, aiming at the production of genetically modified animals, with the certainty that progress in this field of knowledge depends on more information on the mechanisms of interaction between nanostructures, cells and embryos, as well as on its toxicity.

Determination of Shear Bond Strength of Nanocomposite to Porcelain and Metal Alloy

Abstract Objective: To compare porcelain and metal repair done with both nanocomposite and conventional composite. Material and Methods: A total of 30 cylinders were fabricated from Porcelain (I), Porcelain fused to metal (II), and metal (III) substrate each. Control group (A) was bonded with conventional micro-hybrid composite and experimental group (B) was bonded with nanocomposite in a 2 mm thickness. All specimens were thermocycled and stored in distilled water at 37 °C for 7 days. A universal testing machine was used to measure the Shear bond strength (SBS). The difference between bond strengths of the groups was compared using an independent t-test. Results: In all three groups, the SBS was higher in the experimental group as compared to the control group. The use of nanocomposite of metal alloy presented maximum shear bond strength, followed by samples of porcelain fused to metal and finally porcelain, showing the lowest values of SBS. Conclusion: Porcelain and alloys bonded with nanocomposite exhibit enhanced adhesiveness as well as aesthetic and mechanical properties. This subsequently would translate into providing higher clinical serviceability and durability and hence a cost-effective and accessible repair option for human welfare (AU).

Pharmaceutical applications of framework nucleic acids

DNA is a biological polymer that encodes and stores genetic information in all living organism. Particularly, the precise nucleobase pairing inside DNA is exploited for the self-assembling of nanostructures with defined size, shape and functionality. These DNA nanostructures are known as framework nucleic acids (FNAs) for their skeleton-like features. Recently, FNAs have been explored in various fields ranging from physics, chemistry to biology. In this review, we mainly focus on the recent progress of FNAs in a pharmaceutical perspective. We summarize the advantages and applications of FNAs for drug discovery, drug delivery and drug analysis. We further discuss the drawbacks of FNAs and provide an outlook on the pharmaceutical research direction of FNAs in the future.

Vegetable cellulose nanofiber dressing aids in the healing process of third-degree burns? study on rats / Curativo de nanofibras de celulose vegetal auxilia na cicatrização de queimaduras de terceiro grau? estudo em ratos

ABSTRACT Background: The treatment of 3rd degree burns represents a major medical challenge. Pinus vegetable cellulose is a biomaterial with characteristic similar to bacterial cellulose. Aim: To evaluate the safety of cellulose membrane (Pinus sp) in the treatment of 3rd burns in rats and to compare its effectiveness with the bacterial membrane already on the market. Method: Thirty-three Wistar rats were beaten with a 3rd degree burn on back skin by applying water at 98º C for 30 s. Then, they were divided into three groups (n=11): group 1 - simple dressing with gauze; group 2 - dressing with bacterial cellulose membrane; and group 3 - dressing with vegetable cellulose membrane. The animals were maintained for 15 days to check the general clinical status, macroscopic aspect, contraction of the wounds and microscopic analysis for the degree of healing and collagenization. Results: They were clinically well during the experiment. During the removal of the dressing, there was bleeding in the wound of the control group, unlike the groups treated with cellulose membranes, which protected the bed from injury. The macroscopic evaluation showed a greater contraction of the wounds treated with the membranes in relation to the control. A microscopic analysis revealed that most of the wounds were in advanced healing degree with predominance of mature collagen in all groups. Conclusion: Pinus sp cellulose membrane showed efficacy similar to that of the bacterial membrane in the treatment of 3rd degree burns.

RESUMO Racional: O tratamento das queimaduras de 3˚ grau representa grande desafio na área médica. A celulose vegetal de pinus é biomaterial com características semelhantes às da celulose bacteriana. Objetivo: Avaliar a segurança da membrana de celulose vegetal (Pinus sp) no tratamento de queimaduras de terceiro grau em ratos e comparar sua eficácia com a da membrana bacteriana já comercializada. Método: Trinta e três ratos Wistar foram submetidos à queimadura de 3º grau na pele do dorso mediante aplicação de água a 98º C durante 30 s. Em seguida, foram distribuídos em três grupos (n=11): grupo 1 - curativo simples com gaze; grupo 2 - curativo com membrana de celulose bacteriana; e grupo 3 - curativo com membrana de celulose vegetal . Os animais foram avaliados durante 15 dias para verificar o estado clínico geral, aspecto macroscópico, contração das feridas e análise microscópica pelo grau de cicatrização e colagenizacao. Resultados: Permaneceram clinicamente bem durante o experimento. Durante a retirada do curativo houve sangramento na ferida do grupo controle, diferentemente dos grupos tratados com as membranas de celulose, que protegeram o leito da lesão. A análise microscópica mostrou que a maioria das feridas apresentava-se em grau avançado de cicatrização, com predomínio de colágeno maduro em todos os grupos. Houve maior contração das feridas tratadas com as membranas em relação ao grupo controle. Conclus ão: A membrana de celulose de Pinus sp apresentou eficácia semelhante à da membrana bacteriana no tratamento de queimaduras de 3˚ grau.

Green Synthesized Silver Nanostructure Using Rhus coriaria Fruit Extract Inhibits the Growth of Malignant MCF-7 Cell Line

Abstract Rhus coriaria, popularly known as sumac, has been used as a spice powder in the Middle East for centuries. It contains a broad range of naturally occurring compounds such as flavonoids, proteins, anthocyanins and volatile oils. It showed a putative importance in treatment of different disorders including cancers. In the current study, R. coriaria fruit extract was used for green synthesis of silver nanostructures (Ag-NSs) and their anticancer activity was tested against human breast cancer cells (MCF-7). The aqueous fruit extract was prepared. The synthesis of Ag-NSs under different conditions was optimized. The optimal reaction medium comprised 1:2 concentration of fruit extract and 3 mM concentration of silver nitrate solution. The green-synthesized Ag-NSs were confirmed by using UV-Visible spectroscopy at a range 300-700 nm, transmission electron microscopy (TEM), X-ray diffraction (XRD) and zeta potential measurements. The anti-proliferative activity of Ag-NSs was confirmed with inhibitory activity on MCF-7 cell line growth. The results showed that the IC50 values at 24 and 48h were 14.27 and 13.4 μg/ml, respectively. In conclusion the results of this study provide a simple, rapid, non-toxic and eco-friendly protocol for green-synthesis of Ag-NSs, which could be used as an alternative and interesting approach for safe and simple synthesis of Ag nanoparticles for biomedical uses.

Recent advances in layered double hydroxides applied to photoprotection / Recentes avanços dos hidróxidos duplos lamelares aplicados à fotoproteção

ABSTRACT Layered double hydroxides have received more attention from researchers due to their range of applications, ease of synthesis and low cost of production. With broader knowledge about solar radiation effects on the body, the use of sunscreens has become even more important. The ability of some nanostructures, such as layered double hydroxides, to act as matrices has made it possible to obtain improvements in photoprotective formulations, with solutions to problems caused by radiation and sunscreens. This review article brings together the most recent advances of these clays, the layered double hydroxides, applied to photoprotection.

RESUMO Os hidróxidos duplos lamelares vêm ganhando maior atenção de pesquisadores, em decorrência da gama de aplicações, da facilidade de síntese e do baixo custo de produção. Com o crescente conhecimento sobre diversos efeitos da radiação solar sobre o organismo, a utilização de fotoprotetores tem se tornado indispensável. A capacidade de nanoestruturas, como os hidróxidos duplos lamelares, atuarem como matrizes possibilitou melhorias nas formulações fotoprotetoras, tendo em vista os problemas provocados pela radiação, bem como por alguns filtros solares. Este artigo de revisão reúne os avanços mais recentes destas argilas, os hidróxidos duplos lamelares, aplicados à fotoproteção.

Application of nanomaterials in enhancing internal radiotherapy of radionuclide for cancer / 中华核医学与分子影像杂志

The therapeutic efficiency of radionuclides for cancer is closely related to the accumula-tion level, residence time and distribution in tumor, and is also influenced by the radiation resistance and hypoxia microenvironment of tumor. Nanomaterials, with a series of characteristics including special dimen-sion effect and functionally modifiable surface, can not only work as the isotopic carrier to transport nuclide into tumor, but also combine with chemical, thermal or photodynamic therapies to generate synergistic thera-peutic effect or destroy the hypoxic microenvironment of tumor to reduce radiation resistance, thus achieving the radiosensitization effect. This article reviews the application of nanomaterials in enhancing the therapeu-tic efficiency of radionuclide for cancer.

Study on the treatment for abnormality of metal ions with EDTA complexing agent-loaded microsphere sustained release system / 中华骨科杂志

Objective To construct a new sustained-release system,hollow mesoporous silica nanoparticles (HMSNs),to control the release of ethylene diamine tetraacetic acid (EDTA) continuously,effectively and intelligently to treat the abnormal increase of metal ions in vivo.The disulfide bond can be broken or reconstructed with the change of H + concentration to realize the construction of "receptor",and the "valve system" is constructed by blocking cucurbituril and alpha-cyclodextrin through disulfide bond.Thus,the abnormal increase of chromium and cobalt ions in rats can be accurately controlled and maintained at normal levels.Methods HMSNs-EDTA sensitive to H+ was prepared.HMSNs containing functional groups of alpha-cyclodextrin were constructed.The disulfide bond was formed between the HS group at the end of cucurbituril and the HS group of alpha-cyclodextrin as a "switch".Cucurbituril and alpha-cyclodextrin are connected by disulfide bond to form a valve system,which can block silica channels and thus close EDTA.A rat model of elevated chromium and cobalt ions was established by intraarticular injection of CoCrMo nanoparticles suspension into the knee joint.Rat models were randomly divided into three groups:intraperitoneal injection of saline (control group),intraperitoneal injection of traditional "valve system" drug sustained release (IgG-HMSNs-EDTA group),and intraperitoneal injection of H+ sensitive cucurbituril-HMSNs-EDTA sustained release (intelligent sustained release system group).During this process,nanoparticle suspension was injected continuously to observe the changes of serum chromium and cobalt concentration in rats.Results From the release curve of EDTA,it was found that the higher the concentration of H + was,the faster the drug release was (H+ concentration group:2 mmol/L ＞ 1 mmol/L ＞ 0.5 mmol/L ＞ 0.1 mmol/L).It shows that the sensor does control the valve with the change of H+ concentration.Compared with the slow-release body without valve,the release of EDTA in the new intelligent slow-release body is gentler.Within 20 weeks,the concentration of metal ions in the control group increased continuously and slowly due to the absence of EDTA treatment (Chromium 1.08±0.07 ug/L and cobalt 41.14±0.79 ug/L).In the traditional valve group,the metal ions decreased rapidly within 8 weeks and were once lower than the normal values in rats.Subsequently,due to the release of EDTA,metal ions will still increase abnormally (Chromium ion 0.61 ±0.52 ug/L,cobalt ion 28.72± 16.93 ug/L).The intelligent sustained-release system group can more effectively,continuously and accurately control the abnormal changes of chromium and cobalt ions in vivo,and the difference is statistically significant (Chromium ion 0.65±0.13 ug/L,cobalt ion 29.68±3.24 ug/L).Conclusion According to the principle that disulfide bond can be broken or reconstructed with the change of H+ concentration,the application of cucurbituril-HMSNs-EDTA intelligent microsphere sustained release system to treat patients with increased chromium and cobalt ions caused by plants in metal will control the drug release more accurately and intelligently.The intelligent sustained-release system can not only avoid the side effects caused by the rapid and excessive release of drugs,which lead to the disorder of normal trace metal elements in vivo,but also prolong the treatment time,and can maintain the chromium and cobalt ions in rats at normal levels for a long time.

Nanomaterials applied in tumor imaging diagnosis and treatment:an integration tendency / 中国组织工程研究

BACKGROUND: With the rapid development of nano-technology, the research and application of nanomaterials in biomedicine are increasing due to various advantages. It becomes a promising research direction in new anti-tumor methods. OBJECTIVE: To summarize the application of nanomaterials in imaging diagnosis and treatment of tumors. METHODS: The authors retrieved articles about the application of nanomaterials in tumor imaging diagnosis and treatment in WanFang, VIP, Elsevier and PubMed databases. The keywords were "nanophase materials, imaging diagnosis of tumor, nanocarriers, treatment of tumors, biological toxicity" in Chinese and English, respectively. RESULTS AND CONCLUSION: Due to its unique physical and chemical properties and plasticity, nanomaterials can become targeted medical materials that can carry anti-tumor drugs or active factors through specific modifications. Moreover, nanomaterials can adapt to different demands through various modifications and structural changes. Therefore, they have an unlimited prospect in the medical field. Currently, nanomaterials are not independent in the aspects of tumor diagnosis and treatment, but show an integration trend; that is, they are first targeted to tumor tissues, release active drugs during imaging diagnosis, or kill tumors through photothermal transformation.

Sistemas de nanopartículas poliméricas II: estructura, métodos de elaboración, características, propiedades, biofuncionalización y tecnologías de auto-ensamblaje capa por capa (layer-by-layer self-assembly) / Polymeric nanoparticle systems: structure, elaboration methods, characteristics, properties, biofunctionalization and self-assembly layer by layer technologies

Los materiales poliméricos han sido ampliamente investigados para aplicaciones biomédicas, teniendo especial relevancia cuando se encuentran en forma de micro- y nano-partículas. Últimamente se ha ampliado su campo de aplicación al ser conjugados con péptidos y ácidos nucleicos, por lo tanto, el interés en el estudio de este tipo de materiales, así como también en la formulación de nanoestructuras funcionalizadas como materiales, dispositivos y vehículos de transporte de agentes terapéuticos ha aumentado. Las recientes investigaciones en nanosistemas se inspiran en fenómenos naturales que estimulan la integración de señales moleculares y la mimetización de procesos a nivel celular, de tejidos y órganos. Tecnológicamente, la capacidad de obtener nanoestructuras esféricas mediante la combinación de materiales que presenten propiedades distintas a las que ningún otro material individual posee por sí solo, es lo que hace que las nanocápsulas sean particularmente atractivas. Las potenciales ventajas de los sistemas de nanopartículas de tipo polimérico se destacan a lo largo de cada parte de este artículo de revisión. El presente artículo aborda los aspectos más relevantes sobre la estructura, composición y algunos métodos de elaboración de los sistemas nanoparticulados. Además, expone algunos de los trabajos más recientes, centrados en sistemas de nanopartículas basados en polímeros dirigidos a la administración de agentes, publicados en artículos especializados de investigación y revisiones durante los últimos años.

Polymeric materials have been extensively investigated for biomedical applications including micro- and nanoparticles. Modern advances have broadened horizons for application with peptides and nucleic acids. Therefore, interests increased in the formulation of materials, devices and vehicles for transporting therapeutic agents in functionalized nanostructures. Recent nano-systems are inspired by natural phenomena that stimulate the integration of molecular signals and the mimicking of natural cellular processes, at tissue and organ levels. Technologically, the ability to obtain spherical nanostructures, which combine different properties, that no other single material possesses on its own, makes nanocapsules particularly attractive. Potential advantages over polymer nanoparticulate systems are highlighted throughout each part of this review article. Here, we address the most relevant aspects of structure, composition and methods of formulation of nanoparticulate systems. In addition, we outline some of the more recent works focusing on nanosized preparations, based on agent-directed polymers, found in specialized research articles that have emerged in the recent years.

Effect of Au NanoStars/collagen matrix material on oxidative stress damage in ventricular myocytes of newborn rats / 军事医学

Objective To verify antioxidation of Au NanoStars/collagen ( AuNSs/Col ) for ventricular myocytes of newborn rats(NRVMs) by in vitro studies.Methods (1)Different concentrations of AuNSs/Col composite materials were created.The optimum concentration of the material was selected by Live /dead staining and Cell Counting Kit-8 (CCK-8) and Col was used for subsequent experiments .( 2 ) NRVMs were randomly divided into Col group , AuNSs/Col group, H2O2-induced Col group, and H2O2-induced AuNSs/Col group.After 6 h treatment, apoptotic cell morphology and early cell apoptosis rate were observed with Annexin Ⅴ-FITC/propidium iodide ( PI)/4′,6-diamidino-2-phenylindole ( DAPI) and the expressions of apoptosis related proteins-B-cell lymphoma-2 ( Bcl-2 ) and Bcl-2 associated x protein ( Bax ) were detected by Western blotting .Results ( 1 ) Both Live/dead and CCK-8 experiments indicated that the AuNSs/Col composite material with 0.1 mg/ml was nontoxicity to NRVMs and could further promote their proliferation .(2) Compared with the uninduced group , the early apoptosis rate of the Col group and the AuNSs /Col group after H2O2 induction was significantly increased , while the Bcl-2/Bax ratio was decreased , indicating that the oxidative stress damage model was established.After H2O2 induction, compared with the Col group , the early apoptosis rate of the AuNSs/Col group was decreased , but the Bcl-2/Bax ratio was increased .Conclusion AuNSs/Col composite material has protective effect on the oxidative damage of cardiomyocytes cultured in vitro.

Near-infrared spectroscopy and microstructure of the scales of Sabethes ( Sabethes ) albiprivus (Diptera: Culicidae)

ABSTRACT Near-infrared spectroscopy and microstructure of the scales of Sabethes (Sabethes) albiprivus (Diptera: Culicidae). Sabethes (Sabethes) albiprivus Theobald individuals vary considerably in size and color of the reflections of the scales on their thorax, abdomen, antepronotal lobes and occiput. The goal of this study was to investigate and to characterize the differences in the color of the scales among preserved specimens and to analyze the differences in the microstructures of the scales that cover their bodies using near-infrared spectroscopy, and to evaluate whether the latter is efficient in distinguishing the populations. A total of 201 adult females were analyzed for the characterization of color patterns. In addition, absorbance spectra and scanning electron microscope images were obtained from them. As a result of color analysis, two variations were identified, one represented by specimens with yellow or green scales and the other with blue or purple scales. The same two variations were corroborated using NIRS. Analysis of the microstructure of the scales lining the mesonotum, occiput and antepronotal lobes resulted in the same variations. The three methodologies, near-infrared spectroscopy, scanning electron microscopy and coloration of the reflections of the scales revealed two variations within Sa. albiprivus.

The application of electrochemical immunosensors in laboratory diagnosis / 中华检验医学杂志

Electrochemical immunosensors is widely used in clinical laboratory diagnosis for its unique properties such as cost-effective, rapid, sensitive and specific and play a role in POCT and rapid diagnosis.This paper introduces the principle and advantages of electrochemical immunosensor.Biological molecules such as tumor marker, myocardial marker, hormone, pathogenic bacteria, viruses, and autoimmune antibody has carried on the induction,based on the domestic and foreign research results.The advantages and disadvantages of electrochemical immunosensor was evaluated, and the research on its application prospect is analyzed.

Application Progress of DNA Nanostructures in DrugDelivery and Smart Drug Carriers / 分析化学

Nanocarrier systems have been widely used for improving solubility, stability and therapeutic activity of drugs due to their high drug-loading efficiency, good target specificity and long circulation time.To achieve precisely controlled loading and tumor-selective release of drugs, extensive research efforts have been focused on developing nanocarriers with low toxicity, excellent biocomapatibility and biodegradability.As a type of nano-biomaterials with various functions and applications, self-assembled DNA nanostructures explored new ways to develop drug carriers in smart drug delivery based on their well-defined structures, good biocompatibility and stability, high cell membrane permeability and controlled drug releasing property.In this review, we summarized the developing course and the recent advances of DNA nanostructures for drug delivery, including the application of both static and dynamic DNA nanostructures.The application of dynamic DNA nanostructures for controlled drug release showed great potential in smart drug delivery.

Fabrication and characterization of three-dimensional cartilage nano-scaffolds based on extracellular matrix / 军事医学

Objective To produce three-dimensional cartilage nanoscaffolds based on extracellular matrix.Methods Nanoscaffolds of collagen type Ⅱ(Col-Ⅱ), hyaluronic acid(HA)and chondroitin sulfate(CS)were prepared by mixing water,trifluoroethanol and hexafluoroisopropanol as a solvent.The structure, morphology, thermal property, mechanical performance and hydrophobicity of the scaffolds were characterized.Results There were interactions between Col-Ⅱ,HA and CS.The scaffolds were hydrophobic.The Col-Ⅱ triple-helix structure wasn't completely damaged.In the study, scaffold fibers were smooth,slender and dimensionally stable.The scaffolds had good thermal stability and optimal tensile properties could be obtained at the mass ratio of 7:1:1.Conclusion In this study, scaffolds have good thermal, mechanical and structural properties and are expected to be used in cartilage repair.

Comparative evaluation of propofol in nanoemulsion with solutol and soy lecithin for general anesthesia / Avaliação comparativa do propofol em nanoemulsão com solutol e com lecitina de soja para anestesia geral

ABSTRACT INTRODUCTION: The vehicle for propofol in 1 and 2% solutions is soybean oil emulsion 10%, which may cause pain on injection, instability of the solution and bacterial contamination. Formulations have been proposed aiming to change the vehicle and reduce these adverse reactions. OBJECTIVES: To compare the incidence of pain caused by the injection of propofol, with a hypothesis of reduction associated with nanoemulsion and the occurrence of local and systemic adverse effects with both formulations. METHOD: After approval by the CEP, patients undergoing gynecological procedures were included in this prospective study: control (n = 25) and nanoemulsion (n = 25) groups. Heart rate, noninvasive blood pressure and peripheral oxygen saturation were monitored. Demographics and physical condition were analyzed; surgical time and total volume used of propofol; local or systemic adverse effects; changes in variables monitored. A value of p < 0.05 was considered significant. RESULTS: There was no difference between groups regarding demographic data, surgical times, total volume of propofol used, arm withdrawal, pain during injection and variables monitored. There was a statistically significant difference in pain intensity at the time of induction of anesthesia, with less pain intensity in the nanoemulsion group. CONCLUSIONS: Both lipid and nanoemulsion formulations of propofol elicited pain on intravenous injection; however, the nanoemulsion solution elicited a less intense pain. Lipid and nanoemulsion propofol formulations showed neither hemodynamic changes nor adverse effects of clinical relevance.

RESUMO INTRODUÇÃO: O veículo do propofol em soluções a 1 e 2% é a emulsão de óleo de soja a 10%, que pode provocar dor à injeção, instabilidade da solução e contaminação bacteriana. Formulações foram propostas com o objetivo de alterar o veículo e reduzir essas reações adversas. OBJETIVOS: Comparar a incidência de dor à injeção do propofol com a hipótese de redução associada à nanoemulsão e a ocorrência de efeitos adversos locais e sistêmicos com as duas formulações. MÉTODO: Após aprovação pelo Conselho de Ética em Pesquisa, foram incluídos neste estudo prospectivo pacientes submetidas a procedimentos cirúrgicos ginecológicos: grupos controle (n = 25) e nanoemulsão (n = 25). Foram monitorados frequência cardíaca, pressão arterial não invasiva e saturação periférica de oxigênio. Foram analisados dados demográficos e estado físico; tempo cirúrgico e volume total usado de propofol; efeitos adversos locais ou sistêmicos; alterações nas variáveis de monitoramento. Considerou-se significativo valor de p < 0,05. RESULTADOS: Não houve diferença entre os grupos em relação a: dados demográficos, tempos cirúrgicos, volume total usado de propofol, retirada do braço, presença de dor durante a injeção e variáveis de monitoramento. Verificou-se diferença estatística significativa na intensidade da dor no momento da indução da anestesia, com menor intensidade no grupo nanoemulsão. CONCLUSÕES: Ambas as formulações de propofol, lipídica e em nanoemulsão, elicitaram dor à injeção venosa, porém a solução de nanoemulsão promoveu dor em menor intensidade. O propofol lipídico e o propofol em nanoemulsão não apresentaram alterações hemodinâmicas e efeitos adversos de relevância clínica.

Immunofluorescence probe based on fluorescent carbon dots and its application to the special recognition of Escherichia coli / 军事医学

Objective Carbon dots (CDs) are an emerging carbon nano-material which is environmentally-friendly, economical , efficient and stable .Their fluorescence properties can match the semiconductor quantum dot .Moreover , CDs have more excellent biocompatibilities .The purpose of this experiment is to apply CDs to the fluorescent immune probe to make them a new label , which can replace the traditional fluorescent dyes .Methods Using microwave heating method , the high strength fluorescent carbon dots were prepared .Wtih the EDC coupling method , the high strength fluorescent car-bon dots could bond with Escherichia coli antibodies to form a complex immune fluorescent probe .Specific recognition exper-iments were carried out in the model of E.coli O157∶H7.Results CDs were successfully applied to immune recognition of E.coli O157∶H7 and multicolor fluorescence was observed .Conclusion CDs can serve as a label of the fluorescent im-mune probe , and are expected to become a new type of low toxicity biosensor with independent intellectual property rights .

Las nanociencias en el InSTEC y su interacción con las ciencias y tecnologías nucleares / Nanoscience in the InSTEC and its relationship with nuclear science and technologies

En el trabajo se presenta la aplicación de diversas herramientas experimentales y teóricas para el estudio de nanomateriales, así como las investigaciones encaminadas al uso combinado de nanotecnologías y tecnologías nucleares, realizadas en el Instituto Superior de Tecnologías y Ciencias Aplicadas. Se destaca la amplia participación de estudiantes en estas investigaciones, lo que contribuye a la asimilación de los conceptos y métodos de las nanociencias por los graduados de las carreras nucleares.

This paper deals with the application of different experimental and theoretical tools to study nanomaterials as well as research aimed at combining the use of nano- and nuclear technologies carried out at the Higher Institute of Technologies and Applied Sciences. The wide participation of students in the research is highlighted, thus contributing to the assimilation of concepts and methods of nanosciences by the graduates of nuclear careers.