Lysozyme antimicrobial activity against Enterococcus Faecalis - a pilot study / Atividade antimicrobiana da lisozima contra Enterococcus Faecalis - um estudo piloto

O preparo químico-mecânico (PQM) do sistema de canais radiculares é essencial para eliminar tecidos infectados e garantir uma desinfecção adequada. O Hidróxido de Cálcio (HC) combinado com o propilenoglicol é frequentemente utilizado como uma pasta intracanal para desinfecção e medicação intraoperatória. No entanto, algumas bactérias, como o Enterococcus faecalis (E. faecalis), podem resistir aos efeitos do hidróxido de cálcio. O Ultracal® é uma medicação de hidróxido de cálcio de alta qualidade e radiopaco usado em procedimentos endodônticos. Já a lisozima é uma substância com propriedades antimicrobianas encontrada em várias partes do corpo humano e tem sido estudada como uma opção promissora para o tratamento de infecções endodônticas. O objetivo do presente estudo foi avaliar e comparar a atividade antimicrobiana do HC com propilenoglicol, Ultracal® e Lisozima contra E. faecalis. Foram realizadas escavações em placas de petri contaminadas com E. faecalis. Após, foi adicionado as medicações intracanais e as placas foram levadas a estufa a 37°C em aerobiose. Os halos de inibição formados foram medidos em 2, 4 e 7 dias. HC apresentou halos de inibição maiores quando comparado as outras medicações e com maior crescimento com o passar dos dias. A lisozima apresentou apenas ação nas primeiras 48 horas, perdendo seu efeito após esse período. Ambas as medicações com hidróxido de cálcio apresentaram valores crescentes. Baseado nos resultados obtidos, conclui-se que as medicações a base de hidróxido de cálcio demonstraram melhor ação contra E. faecalis em ação direta.

The chemical-mechanical preparation (CMP) of root canals system is essential to eliminate infected tissues and ensure adequate disinfection. Calcium hydroxide (CH) combined with propylene glycol is often used as an intracanal medication for intraoperative disinfection and medication. However, some bacteria, such as Enterococcus faecalis (E. faecalis), may resist the effects of calcium hydroxide. Ultracal® is a high-quality radiopaque calcium hydroxide medication used in endodontic procedures. Lysozyme, on the other hand, is a substance with antimicrobial properties found in various parts of the human body and has been studied as a promising option for the treatment of endodontic infections. The aim of this study was to evaluate and compare the antimicrobial activity of CH with propylene glycol, Ultracal®, and Lysozyme against E. faecalis. Petri plates contaminated with E. faecalis were excavated, intracanal medications were added, and the plates were incubated at 37°C in aerobic conditions. The inhibition halos formed were measured at 2, 4, and 7 days. CH showed larger inhibition halos compared to the other medications and exhibited increased growth over the days. Lysozyme showed activity only in the first 48 hours, losing its effect after this period. Both medications with calcium hydroxide showed increasing values. Based on the results obtained, it is concluded that calcium hydroxide-based medications demonstrated better action against E. faecalis in direct action.

Existem diferenças entre homens e mulheres quanto aos fatores associados à ingestão de cálcio? / Are there differences between men and women with respect to the factors associated with calcium intake?

Resumo O objetivo do artigo é verificar se existem diferenças entre os sexos quanto aos fatores que se associam à ingestão de cálcio. Estudo realizado com dados de inquérito de saúde, em amostra de 1.640 indivíduos de 20 anos ou mais residentes no município de Campinas-SP. A ingestão de cálcio foi obtida por meio de um recordatório de 24 horas (R24h) e analisada segundo variáveis sociodemográficas, de comportamentos de saúde, frequência de refeições e índice de massa corporal (IMC); a presença de associações foi verificada por meio de testes de regressão linear múltipla. O perfil de fatores associados à ingestão de cálcio diferiu entre os sexos. A prática de atividade física no contexto de lazer só se associou ao consumo de cálcio no sexo masculino, enquanto cor da pele, tabagismo, renda, excesso de peso e frequência do café da manhã mostraram associação apenas no sexo feminino. Escolaridade e realização de lanches intermediários mostraram-se associadas à ingestão de cálcio em ambos os sexos. A análise aponta segmentos da população feminina e masculina em que a importância da ingestão de cálcio precisa ser mais enfatizada; além disso, alerta para a importância do desenvolvimento de análises de saúde estratificadas por sexo em decorrência de diferentes padrões comportamentais que prevalecem entre os sexos.

Abstract The scope of this article is to verify if there are differences in factors associated with calcium intake between men and women. It is based on a study conducted with data from a health survey in a sample of 1641 individuals aged 20 years or more living in the urban area of the city of Campinas, in the State of São Paulo. Calcium intake was obtained from a 24-hour recall (24hr recall method) and analyzed according to sociodemographic variables, health behavior, frequency of meals and body mass index (BMI). The existence of associations was verified by multiple linear regression tests, and it was detected that the profile of associated factors differed between genders. Physical exercise in the leisure context was only associated with calcium intake in males, while skin color, smoking, income, overweight/obesity, and frequency of having breakfast only revealed an association in females. Schooling and having snacks were associated with calcium intake in both sexes. The analysis of the associated factors indicates segments of the female and male population in which the importance of calcium intake needs to be more closely examined. Furthermore, it highlights the importance of conducting health analyses stratified by sex due to the different behavioral patterns that prevail between the sexes.

Liberación de aluminio de tres selladores endodónticos biocerámicos. Un ensayo in vitro / Aluminum release from three bioceramic endodontic sealers. An in vitro test

Objetivos: Determinar y comparar la liberación de aluminio (Al) a partir de la formulación química de los selladores endodónticos biocerámicos Bio-C® Sealer, AHPlus® Biocerámico y BioLine Sealer Z. Materiales y métodos: Se prepararon cinco (n=5) muestras de cada uno de los materiales y se determinó el contenido de Al liberado mediante espectrometría de masa con plasma inductivo acoplado ICP-MS. Los resultados se analizaron mediante ANOVA y la prueba de comparación múltiple de Tukey con un nivel de significación de 0,05. Resultados: La proporción de Al liberado por los selladores biocerámicos analizados fue de 0,04 mg/g para Bio-C® Sealer y BioLine Sealer Z y de 0,0012 mg/g para AHPlus® Bioceramic Sealer. ANOVA mostró un nivel significativo para el factor material (p<0,0001). La prueba de Tukey reveló que la liberación de Al de AHPlus®Bioceramic Sealer, fue significativamente menor a la de los otros dos selladores (p<0,05). Conclusión: La proporción de Al liberado por AHPlus® Bioceramic Sealer es menor que Bio-C® Sealer y BioLine Sealer Z. Si bien los tres selladores liberaron Al, ninguno de los valores superó aquellos de la ingesta media diaria de un individuo adulto, por lo que no representaría un riesgo biológico para su uso clínico en humanos.(AU)

Aim: Determine and compare the lease of aluminum (Al) from three bioceramic endodontic sealers Bio- C® Sealer, AHPlus ® Bioceramic Sealer and BioLine Sealer Z. Materials and methods: Five (n=5) samples of each of the materials were prepared and the released Al content was determined by mass spectrometry with inductively coupled plasma ICP-MS. The results were analyzed with ANOVA and Tukey´s multiple comparison test with a significance level of p<0.05. Results: The proportion of Al released by the bioceramic sealers analyzed was 0.04 mg/g for Bio-C® Sealer and BioLine Sealer Z, and 0.0012 mg/g for AH Plus® Bioceramic Sealer. ANOVA showed a significant level for the factor material (p<0.0001). Tukey's test revealed that the Al release from AH Plus® Bioceramic Sealer was significantly lower than that of the other two sealers (p<0.05). Conclusions: The proportion of Al released by AH Plus® Bioceramic Sealer is lower than that of Bio-C® Sealer and BioLine Sealer Z. Although all three sealers released Al, none of the values exceeded the average daily intake for an adult individual, and therefore, they would not represent a biologic risk for clinical use in humans.(AU)

Função do Ventrículo Direito e Estresse Oxidativo Melhoram com a Administração de Hormônios da Tireoide e Suco de Uva em um Modelo de Hipertensão Pulmonar / Right Ventricular Function and Oxidative Stress Improve with the Administration of Thyroid Hormones and Grape Juice in a Pulmonary Hypertension Model

Resumo Fundamento A remodelação adversa dos vasos pulmonares eleva a pressão pulmonar e provoca hipertensão arterial pulmonar (HAP). A HAP resulta em aumento da pós-carga do ventrículo direito (VD), causando hipertrofia ventricular e consequente insuficiência cardíaca. Não existe um tratamento específico para o remodelamento desadaptativo do VD secundário à HAP. Objetivos Este estudo tem como objetivo explorar duas abordagens terapêuticas, o suco de uva (SU) e os hormônios tireoidianos (HT), no tratamento do estresse oxidativo induzido pela HAP e nas alterações funcionais cardíacas. Métodos Parâmetros ecocardiográficos relacionados à resistência dos vasos pulmonares (relação TA/TE), contratilidade do VD (ESPAT) e função diastólica do VD (relação dos picos E/A) foram avaliados. Além disso, foram medidos ROS totais, peroxidação lipídica, enzimas antioxidantes, proteínas de manipulação de cálcio, expressão de proteínas pró-oxidantes e antioxidantes. Valores de p<0,05 foram considerados estatisticamente significativos. Resultados Ambos os tratamentos, com SU e HT, demonstraram uma redução na resistência pulmonar (~22%), além de melhorias na ESPAT (inotropismo ~11%) e na relação TA/TE (~26%) (p<0,05). Não houve alterações entre os grupos na relação do pico de E/A. Embora ROS e TBARS não tenham sido estatisticamente significativos, os tratamentos com SU e HT diminuíram os níveis de xantina oxidase (~49%) e normalizaram a expressão de HSP70 e proteínas de manipulação de cálcio (p<0,05). No entanto, apenas o tratamento com HT melhorou a função diastólica (~50%) e aumentou o imunoconteúdo de NRF2 (~48%) (p<0,05). Conclusões Até onde sabemos, este estudo é pioneiro ao mostrar que o HT administrado em conjunto com o SU promoveu melhorias funcionais e bioquímicas em um modelo de HAP. Além disso, nossos dados sugerem que os tratamentos com SU e HT se mostraram cardioprotetores, sejam combinados ou não, e exibiram seus benefícios ao modular o estresse oxidativo e as proteínas de manipulação do cálcio.

Abstract Background Adverse remodeling of lung vessels elevates pulmonary pressure and provokes pulmonary arterial hypertension (PAH). PAH results in increased right ventricle (RV) afterload, causing ventricular hypertrophy and the onset of heart failure. There is no specific treatment for maladaptive RV remodeling secondary to PAH. Objectives This study aims to explore two therapeutic approaches, grape juice (GJ) and thyroid hormones (TH), on PAH-induced oxidative stress and cardiac functional changes. Methods Parameters of echocardiography related to lung vessel resistance (AT/ET ratio), RV contractility (TAPSE), and RV diastolic function (E/A peaks ratio) were evaluated. Also, total ROS, lipid peroxidation, antioxidant enzymes, calcium handling proteins, pro-oxidant and antioxidant protein expression were measured. Values of p<0.05 were considered statistically significant. Results Both GJ and TH treatments demonstrated reductions in pulmonary resistance (~22%) and improvements in TAPSE (inotropism ~11%) and AT/ET ratio (~26%) (p<0.05). There were no changes amongst groups regarding the E/A peak ratio. Although ROS and TBARS were not statistically significant, GJ and TH treatments decreased xanthine oxidase (~49%) levels and normalized HSP70 and calcium handling protein expression (p<0.05). However, only TH treatment ameliorated diastolic function (~50%) and augmented NRF2 immunocontent (~48%) (p<0.05). Conclusions To the best of our knowledge, this study stands as a pioneer in showing that TH administered together with GJ promoted functional and biochemical improvements in a PAH model. Moreover, our data suggest that GJ and TH treatments were cardioprotective, combined or not, and exhibited their beneficial effects by modulating oxidative stress and calcium-handling proteins.

Apicificação, apicogênese e revascularização, conceitos e conduta clínica: uma revisão de literatura / Apexification, apexogenesis and revascularization, concepts and clinical management: a literature review

O tratamento endodôntico de dentes com rizogênese incompleta requer uma atenção especial, uma vez que o tratamento convencional é inviável e devemos evitar a perda dos dentes permanentes. Na maioria das vezes, as causas que interrompem a formação radicular são os traumatismos dentários e as cáries extensas, que podem atingir a polpa coronária, podendo levar, inclusive, à necrose pulpar. Atualmente, esses casos têm sido tratados por meio da apicificação, apicogênese e da revascularização pulpar, com uso de medicações a base de hidróxido de cálcio, antibiótico e MTA (Agregado trióxido mineral). Nessas técnicas, a intenção é induzir o desenvolvimento radicular completo ou o fechamento apical por tecido duro calcificado. O objetivo deste trabalho foi realizar uma breve revisão de literatura, utilizando artigos científicos disponíveis nas plataformas Café (UFF), Scielo e PubMed, a fim de descrevermos os conceitos de apicificação, apicogênese e revascularização, expondo as suas indicações e condutas clínicas ideais para a realização destes tratamentos. Pode-se concluir que são procedimentos clínicos simples e de conhecimento extremamente importantes para qualquer cirurgião-dentista, uma vez que são tratamentos emergenciais bastante comuns no dia a dia. Além disso, sabe-se da necessidade de manter um dente permanente sadio na boca, que pode evitar grandes problemas no futuro.

Endodontic treatment on teeths with incomplete rhizogenesis requires special attention, since conventional treatment is infeasible and we must avoid the loss of permanent teeth. Most often, the causes that interrupt root formation are dental trauma and extensive caries, which can reach the coronary pulp and may even lead to pulpal necrosis. Currently, these cases have been treated through apexification, apexogenesis and pulpal revascularization, with the use of calcium hydroxide, antibiotic and MTA (Aggregate mineral trioxide) base medications. In these techniques, the intent is to induce complete root development or apical closure by calcified hard tissue. The objective of this work was to carry out a review of literature, using scientific articles available on the Café platform (UFF), Scielo and PubMed, in order to describe the concepts of apexification, apexogenesis and revascularization, exposing their indications and ideal clinical procedures for the realization of these treatments. It can be concluded that they are simple clinical procedures and of knowledge extremely important for any dentist, since they are emergency treatments that are quite common day by day. In addition, it is known that one needs to maintain a permanent healthy tooth in the mouth, which can avoid major problems in the future.

Ingesta de calcio y vitamina D: relación con exceso de peso en población costarricense / Calcium and vitamin D intake, its relationship with weight excess in Costa Rican population

Introducción: La presencia de sobrepeso y obesidad aumentan la morbimortalidad de la población latinoamericana. La deficiencia de micronutrientes como el calcio y la vitamina D se han relacionado con un aumento del riesgo de obesidad. Objetivo: Determinar la relación entre la ingesta de vitamina D y de calcio con los factores de riesgo para obesidad en la población urbana costarricense incluidas en el Estudio ELANS. Materiales y métodos: Se incluyeron 798 participantes costarricenses del Estudio ELANS. Se determinó la distribución del consumo de calcio y vitamina D según las características socioeconómicas, la actividad física y los datos antropométricos. Se compararon los grupos con las pruebas U de Mann ­ Whitney y Kruskal-Wallis. Se realizaron modelos de regresión lineal y logística. Resultados: El consumo de calcio y vitamina D fue inadecuado en más del 98% de los participantes. Las mujeres, las personas con menor nivel socioeconómico, baja actividad física, de menor edad, con exceso de peso y obesidad abdominal presentaron un consumo menor de calcio y de vitamina D. El consumo de calcio y vitamina D es mayor en los grupos que tienen un menor IMC (p= 0,023 para calcio y p= 0,252 para vitamina D). Las personas con menor circunferencia de la cintura tuvieron más consumo de calcio y vitamina D (p= 0,002 para calcio y p= 0,008 para vitamina D). No hubo asociación del consumo en los modelos de regresión. Conclusiones: El consumo de calcio y vitamina D es deficiente en la población urbana costarricense y, presentó una relación inversa con el IMC(AU)

ntroduction: The presence of overweight and obesity increase the morbimortality of people in Latin America. Micronutrient deficiencies, such as calcium and vitamin D, are associated with an increased risk of obesity. Objective: To determine the relationship between vitamin D and calcium intake with risk factors for obesity in the Costa Rican urban population included in the ELANS Study. Materials and methods: For this analysis we used the 798 Costa Rican participants of the study (ELANS). The distribution of calcium and vitamin D intake was determined according to socioeconomic status, physical activity, and anthropometric measures. The Mann ­ Whitney and Kruskal-Wallis U tests were used, as well as linear and logistic regression models were performed. Results: Calcium and vitamin D intake was inadequate in more than 98% of the participants. Women, individuals with a lower socioeconomic level, low physical activity, younger age and those with excess weight and abdominal obesity presented lower consumptionofcalciumandvitamin D. Theconsumption of calcium and vitamin D was greater in the groups that have a lower BMI (p= 0.023 for calcium and p= 0.252 for vitamin D). The smaller the waist circumference, the greater the consumption of calcium and vitamin D (p= 0.002 for calcium and p= 0.008 for vitamin D). No association of the consumption of calcium and vitamin D was found in the regression models. Conclusions: Consumption of calcium and vitamin D is deficient in the Costa Rican urban population, and more prevalent among those with higher BMI. Arch Latinoam Nutr 2024(AU)

Prevalencia de osteopenia del prematuro antes y después de la implementación de una estrategia temprana de manejo fosfocálcico / Prevalence of osteopenia of prematurity before and after implementing an early strategy with the use of calcium and phosphate

Introducción. Con el uso de la nutrición parenteral agresiva en recién nacidos de muy bajo peso, se detectaron alteraciones del metabolismo fosfocálcico. En 2016 se implementó una estrategia de prevención a través del monitoreo fosfocálcico y su suplementación temprana. El objetivo fue estudiar si esta estrategia disminuye la prevalencia de osteopenia e identificar factores de riesgo asociados. Población y métodos. Estudio cuasiexperimental que comparó la prevalencia de osteopenia entre dos grupos: uno después de implementar la estrategia de monitoreo y suplementación fosfocálcica (01/01/2017-31/12/2019), y otro previo a dicha intervención (01/01/2013-31/12/2015). Resultados. Se incluyeron 226 pacientes: 133 pertenecen al período preintervención y 93 al posintervención. La prevalencia de osteopenia global fue del 26,1 % (IC95% 20,5-32,3) y disminuyó del 29,3 % (IC95% 21,7-37,8) en el período preintervención al 21,5 % (IC95% 13,6-31,2) en el posintervención, sin significancia estadística (p = 0,19). En el análisis multivariado, el puntaje NEOCOSUR de riesgo de muerte al nacer, recibir corticoides posnatales y el período de intervención se asociaron de manera independiente a osteopenia. Haber nacido luego de la intervención disminuyó un 71 % la probabilidad de presentar fosfatasa alcalina >500 UI/L independientemente de las restantes variables incluidas en el modelo. Conclusión. La monitorización y suplementación fosfocálcica precoz constituye un factor protector para el desarrollo de osteopenia en recién nacidos con muy bajo peso al nacer.

Introduction. With the use of aggressive parenteral nutrition in very low birth weight infants, alterations in calcium and phosphate metabolism were detected. In 2016, a prevention strategy was implemented through calcium phosphate monitoring and early supplementation. Our objective was to study whether this strategy reduces the prevalence of osteopenia and to identify associated risk factors. Population and methods. Quasi-experiment comparing the prevalence of osteopenia between two groups: one after implementing the calcium phosphate monitoring and supplementation strategy (01/01/2017­12/31/2019) and another prior to such intervention (01/01/2013­12/31/2015). Results. A total of 226 patients were included: 133 in the pre-intervention period and 93 in the post-intervention period. The overall prevalence of osteopenia was 26.1% (95% CI: 20.5­32.3) and it was reduced from 29.3% (95% CI: 21.7­37.8) in the pre-intervention period to 21.5% (95% CI: 13.6­31.2) in the post-intervention period, with no statistical significance (p = 0.19). In the multivariate analysis, the NEOCOSUR score for risk of death at birth, use of postnatal corticosteroids, and the intervention period were independently associated with osteopenia. Being born after the intervention reduced the probability of alkaline phosphatase > 500 IU/L by 71%, regardless of the other variables included in the model. Conclusion. Calcium phosphate monitoring and early supplementation is a protective factor against the development of osteopenia in very low birth weight infants.

Activation of A1 reactive astrocytes in the medullary dorsal horn of rats participates in the chronification of trigeminal neuralgia / 中南大学学报(医学版)

Objective:The activation of astrocytes is an important process in the formation of chronic pain.This study aims to observe the activation of A1 reactive astrocytes in the medullary dorsal horn in the rat model of trigeminal neuralgia,and to explore the mechanism of central sensitization caused by A1 reactive astrocyte. Methods:The adult male rats were randomly divided into a sham group and a chronic constriction injury of infraorbital nerve(ION-CCI)group.The facial mechanical pain threshold and thermal withdrawal latency were measured before the operation and on the 1st,3rd,7th,10th,and 14th day after the operation.After pain behavior observation,the expression of glial fibrillary acidic protein(GFAP)in the medullary dorsal horn was observed by immunohistochemistry and immunofluorescence colocalization of GFAP,complement 3(C3)/S100A10,and 4',6-diamidino-2-phenylindole(DAPI)was analyzed.Primary astrocytes were cultured and randomly divided into a naive group and a DHK group.The DHK group was treated with 1 mmol/L of astrocyte activation inhibitor dihydrokainic acid(DHK).Fura-2/AM was used to stain the astrocytes and the calcium wave of the 2 groups under the stimulation of high potassium was recorded and compared.The expression of C3 was detected by Western blotting. Results:The facial mechanical pain threshold and thermal withdrawal latency of the ION-CCI group were significantly lower than those of the sham group(both P<0.05).There were a large number of GFAP positive astrocytes in the medullary dorsal horn of the ION-CCI group.The fluorescence intensity of GFAP in the ION-CCI group was higher than that in the sham group(P<0.05).GFAP and C3/S100A10 were co-expressed in astrocytes.Compared with the sham group,the fluorescence intensity of C3 and the protein expression of C3 in the ION-CCI group were increased(both P<0.05).The expression of C3 in ION-CCI group was significantly increased(P<0.05).Compared with the naive group,the C3 protein expression was significantly decreased in the DHK group(P<0.05).The intensity of calcium fluorescence was increased after high potassium stimulation in both groups.Furthermore,the peak and increase amplitude of calcium fluorescence in the naive group were much higher than those in the DHK group(both P<0.05). Conclusion:A1 reactive astrocytes in the medullary dorsal horn of trigeminal neuralgia model rats are increased significantly,which may participate in central sensitization of trigeminal neuralgia by impacting astrocyte calcium wave.

Research progress in data processing methods of neuronal soma calcium imaging / 军事医学

The recording and analysis of activities of calcium signals in neurons is of critical importance in the field of neuroscience.Over the past three decades,various fluorescent calcium imaging techniques not only have been used in the imaging study of functional activities of neuronal communities,but also can be combined with specific markers to record the functional activities of specific types of neuronal communities.To analyze neural activities at the cellular level,a series of preprocessing such as motion correction,cell body recognition,calcium signal extraction and peak deconvolution is required for the collected video.However,current methods for manual preprocessing are time-consuming and laborious,so computer automatic analysis technology is urgently needed to quickly repair the jitter in the video,identify the position and outline of a single cell,extract its activity trajectory and infer the action potential peak.In this paper,the methods of calcium imaging data processing used in recent years are summarized,and the future developments are predicted.

HDCGUnet:a neural network for image segmentation of calcium imaging / 军事医学

Objective To build a neural network based on the Unet infrastructure for recognition and segmentation of two-dimensional calcium imaging fluorescence images.Methods The in vivo miniaturized two-photon microscope(mTPM)was used for brain calcium imaging in freely moving mice.The imaging data was motion corrected using the NoRMCorre algorithm and processed using ImageJ software to obtain the original images after correction,and the labels were produced using the Labelme software.The neural network HDCGUnet was built using the original images and labels for training,and optimized to improve the model structure according to the training effect.Finally,the evaluation indexes were selected and compared with those of other models to verify the utility of this model.Results The HDCGUnet model,which was collected and made on our own,performed best in the two-photon calcium imaging dataset compared to other models,and performed well on the BBBC dataset either.Conclusion The HDCGUnet model provides a novel alternative for the recognition and segmentation of two-photon calcium imaging images.

Inhibitory effects of allicin effective component DATS on Enterococcus faecalis bofilm:An in vitro Study / 实用口腔医学杂志

Objective:To investigate the antibacterial efficacy of allicin effective component,dially trisulfide(DATS),on the biofilms of Enterococcus faecalis(E.faecalis)in vitro.Methods:60 healthy single root canal permanent teeth were selected.After cleaning and autoclaving,15 teeth without infection were used in the negative control group,45 teeth were contaminated by E.faecalis and incubated for 28 days as the infection models and devided into 3 groups(n=15)as below:DATS group,Calcium hydroxide group and positive(without antibacteria treatment)control group.The minial inhibition concentration(MIC)and minial bactericidal concentrition(MBC)of DATS on E.feacalis were studied with doubling diluting method.At the day 1,2 and 7 of the exprement,the 4 mg of root canal in-ner dentin powder,5 specimens of each group were sespectively transfered into sterile bottle containing 2 mL BHI broth and cultured at 37 ℃ 5％CO2 for 72 h,the turbitity of the upper layer of liquid of the culture was measured.Results:MIC and MBC(μg/mL)of DATS to E.feacalis was 2 560 and 5 120 repsectively.At the first day,turbidity in the DATS group was the lowest(P＜0.05).At the third day,turbidity showed no difference between DATS group and negative control group(P=0.454).At the 7th day,between calcium hydroxide and the negative control group,P＜0.05.Conclusion:DATS may suppress E.faecalis in the biofilm in vitro.

Effect of neodymium-doped:yttrium aluminum perovskite laser combined with two kinds of remineralizers on remineralization of early enamel caries / 中国组织工程研究

BACKGROUND:In recent years,a variety of lasers have been widely used in various diseases related to stomatology,including the prevention and treatment of dental caries. OBJECTIVE:To investigate the effect of neodymium-doped:yttrium aluminum perovskite(Nd:YAP)laser combined with two remineralizers on early enamel caries in vitro. METHODS:Early enamel caries models in vitro were artificially established by 60 enamel blocks and randomly divided into 6 groups(n=10).Group A did not undergo any treatment but underwent extracorporeal pH circulation.Group B underwent remineralization of dentin(the main component of casein phosphopeptide-amorphous calcium phosphate composite)and extracorporeal pH circulation.Group C underwent remineralization treatment of Sensodyne toothpaste(the main component of bioactive glass)and then underwent extracorporeal pH circulation.Group D received Nd:YAP laser irradiation and extracorporeal pH circulation.Group E was treated with Nd:YAP laser irradiation,with remineralization of dentin,and then with extracorporeal pH circulation.In group F,Nd:YAP laser irradiation was performed,and then Sensodyne toothpaste was used for remineralization,and the extracorporeal pH circulation was performed;the remineralization treatment was conducted twice a day,and the experimental period was 20 days.Group G was a normal control group,without caries or remineralization,but only underwent extracorporeal pH circulation.After the experiment,the microhardness,morphology and Ca/P ratio of the dental enamel surface were measured in each group. RESULTS AND CONCLUSION:(1)The surface microhardness value of dental enamel in groups B,C and D was higher than that in group A(P<0.000 1);the surface microhardness value of dental enamel in groups E and F was significantly higher than that in groups B,C and D(P<0.000 1),and the surface microhardness value of dental enamel in group F was significantly higher than that in group E(P<0.000 1).(2)Scanning electron microscopy showed that there were a lot of demineralized pores on the enamel surface of group A.There were mineral deposits on the enamel surface of group B,which were uneven and loose.In group C,there were a lot of mineral deposits on the enamel surface,and demineralized pores were found between the calcified masses.The enamel surface of group D was relatively flat;the demineralized pores were significantly smaller than that of group A,and the enamel column interstitium was damaged.In group E,the mineral deposits on the enamel surface were thicker and the demineralized pores were significantly reduced.The mineralized substances deposited on the enamel surface of group F were most dense and uniform and the demineralized pores were small.(3)The Ca/P ratio on the enamel surface of groups B and C was significantly higher than that of group A(P<0.000 1);the Ca/P ratio on the enamel surface of group E was significantly higher than that of groups B,C and D(P<0.000 1),and the Ca/P ratio on the enamel surface of group F was higher than that of group E(P<0.001).(4)These findings indicate that bioactive glass,casein phosphopeptide-amorphous calcium phosphate composite,and Nd:YAP laser after enamel demineralization can promote the remineralization of early enamel caries.Nd:YAP laser combined with bioactive glass or casein phosphopeptide-amorphous calcium phosphate composite can further strengthen the remineralization of dental enamel caries,and the combination of Nd:YAP laser and bioactive glass has the best effect.

Effects of different culture media on quality and developmental potential of mouse oocytes after in vitro maturation / 中国组织工程研究

BACKGROUND:In recent years,the demand for in vitro maturation of immature oocytes has increased.Oocyte maturation is affected by many factors,among which the selection of medium is particularly important,and there is currently no unified plan. OBJECTIVE:To compare the in vitro maturation of germinal vesicle stage oocytes with different maturation media and to investigate its effects on oocyte quality and developmental potential. METHODS:Germinal vesicle oocytes were matured in G-1TM PLUS medium,CZB medium and M16 medium,and mature oocytes in vivo were used as control group to compare in vitro fertilization and early embryo development among various groups.The immunofluorescence method was used to evaluate mitochondrial function in mature oocytes of each group.Calcium oscillation was detected by confocal microscopy real-time imaging system. RESULTS AND CONCLUSION:(1)There was no significant difference in the first polar body ejection rate among the three groups(P>0.05).(2)The rate of in vitro fertilization was higher in the G-1TM PLUS group(52.86±11.24)%than that in the M16 group(37.76±6.70)%and the CZB group(30.62±5.51)%.The blastocyst rate was lower in the CZB group(36.23±6.63)%than that in the control group(78.16±4.17)%,G-1TM PLUS group(55.75±7.63)%and M16 group(53.36±6.33)%.(3)Compared with the control group,the length-to-width ratio of the spindle in the CZB group increased(P<0.005).(4)The mitochondrial function of the CZB group was worse than that of the control group,G-1TM PLUS group and M16 group,and abnormal mitochondrial agglutination occurred in the CZB group.(5)The frequency of calcium oscillations in the CZB and M16 groups was significantly higher than that in the G1 and control groups.In conclusion,during in vitro maturation of mouse oocytes,in vitro maturation rate was not significantly different among G-1TM PLUS,CZB and M16 media,but the G-1TM PLUS medium had a higher rate of fertilization and blastocyst formation.

Screening and analysis of differentially expressed genes for calcium homeostasis in ameloblasts with high fluoride intervention / 中国组织工程研究

BACKGROUND:Fluorosis is a disorder of enamel development caused by long-term intake of large amounts of fluoride during enamel development. OBJECTIVE:To further explore the molecular mechanism of dental fluorosis formation by screening the differentially expressed genes associated with calcium homeostasis in ameloblasts by transcriptome sequencing technology. METHODS:LS8 cells were treated with 0,0.4,0.8,1.6,3.2 and 6.4 mmol/L sodium fluoride(NaF)for 24,48 and 72 hours to observe the effects of different concentrations of NaF on the morphology,cell activity and intracellular Ca2+ concentration of LS8 cells.The differentially expressed genes were screened by transcriptome sequencing and validated. RESULTS AND CONCLUSION:After 24 hours of treatment,the cells treated with 0,0.4,and 0.8 mmol/L NaF were in good growth condition,with increased cell number and clear cell outline.When the NaF concentration was≥1.6 mmol/L,the cells were gradually shrunken and became smaller and the number of cells decreased with the increase of NaF concentration.After 48 and 72 hours of treatment,the number of cells increased in the 0,0.4 mmol/L NaF groups,while gradually decreased in the 0.8,1.6,3.2 mmol/L NaF groups,with rounded and smaller cell morphology.The cells in the 6.4 mmol/L NaF group were shrunken,rounded and suspended in the medium,with almost no adherent cells.When treated with the same concentration of NaF,LS8 cells were in optimal growth after 24 hours of treatment.Results from cell counting kit-8 assay showed that when treated with the same concentration of NaF,the cell activity decreased with the increase of treatment time;when the treatment time was the same,the cell activity decreased with the increase of NaF concentration.After 24 hours of treatment,the intracellular Ca2+ concentration increased with the increase of NaF concentration.Transcriptome sequencing analysis identified genes involved in the regulation of cellular calcium homeostasis:Hsp90b1,Canx,Calr,and Hspa5 that were significantly upregulated(P＜0.05)and Cacna1a that was significantly downregulated(P＜0.05).To conclude,the inhibitory effect of NaF on LS8 cell proliferation may be related to the abnormal increase in intracellular Ca2+ concentration,and the mechanism may be caused by the upregulation of the expression of protein processing and synthesis pathways Hsp90b1,Canx,Calr,and Hspa5 and the downregulation of the expression of calcium signaling pathway Cacna1a.

Calcium phosphate combined with recombinant human bone morphogenetic protein-2 in repair and reconstruction of tibial infectious bone defects / 中国组织工程研究

BACKGROUND:Although the clinical application of Masquelet technology has achieved extensive success,the research on optimizing all aspects of Masquelet technology is still being carried out.The focus of doctors is to speed up bone healing and shorten bone healing time after bone grafting. OBJECTIVE:To observe the effect of calcium phosphate combined with recombinant human bone morphogenetic protein-2 in repairing tibial infectious bone defects. METHODS:Thirty-one patients with tibial infectious bone defects were selected from The People's Hospital of Jianyang City from June 2017 to June 2022.They were treated with the Masquelet membrane induction technique.During the second stage of operation,they were divided into a control group(n=15)and a study group(n=16)according to different bone graft materials.Patients in the control group were implanted with autologous bone/allogeneic bone particles,and those in the study group were implanted with calcium phosphate combined with recombinant human bone morphogenetic protein-2/autologous bone particles.Six months after the second stage operation,peripheral blood inflammatory indexes such as white blood cell count,C-reactive protein,and erythrocyte sedimentation rate were detected.Imaging bone healing time,bone healing X-ray score,bone defect healing classification,and adjacent joint function were recorded.The presence of nail track infection,implant absorption,pain,and infection in the bone extraction area were observed. RESULTS AND CONCLUSION:(1)White blood cell count,erythrocyte sedimentation rate,and C-reactive protein levels of the two groups 6 months after the second stage operation were significantly lower than those before the first stage operation(P<0.05).There was no significant difference in each index between the two groups(P>0.05).(2)Bone healing time in the study group was shorter than that in the control group(P<0.05).(3)The Samantha X-ray score of the study group 6 months after the second stage operation was higher than that of the control group(P<0.05).The excellent and good rate of bone defect healing and adjacent joint function of the study group was higher than that of the control group(P<0.05).There was no significant difference in the recurrence rate and complication rate between the two groups(P>0.05).(4)These findings indicate that the effect of calcium phosphate combined with recombinant human bone morphogenetic protein-2 during the second stage operation of the Masquelet membrane induction technique in the treatment of tibial infectious bone defect is good and safe.

Physicochemical properties and cytocompatibility of biomimetically precipitated nanocrystalline calcium phosphate granules / 中国组织工程研究

BACKGROUND:Artificially synthesized hydroxyapatite ceramic granules are widely used in clinical practice to repair large-volume bone defects.However,the osteogenic effect of hydroxyapatite ceramic granules prepared by high-temperature sintering is limited by their low degradability and bioactivity. OBJECTIVE:To prepare biomimetically precipitated nanocrystalline calcium phosphate granules by a novel low-temperature deposition technique,and to characterize their physicochemical properties and cytocompatibility. METHODS:Biomimetically precipitated nanocrystalline calcium phosphate granules were prepared using a modified supersaturated calcium phosphate mineralization solution and a repeated settling and decantation washing method.Hydroxyapatite bioceramic granules were used as the control.The morphology and phase composition of the granules were characterized by scanning electron microscopy,X-ray diffraction,and Fourier transform infrared spectroscopy.The specific surface area,porosity distribution,hardness and hydrophilicity of the granules were characterized by BET-N2 method,hardness test,and contact angle test.The adsorption properties of the granules for bovine serum albumin and fetal bovine serum protein were determined by bicinchoninic acid assay.The two kinds of granules or granule extracts were co-cultured with human umbilical cord mesenchymal stem cells,and the cell proliferation was detected by MTT assay. RESULTS AND CONCLUSION:(1)Scanning electron microscopy showed that the surface of the two kinds of particles was slightly rough and accompanied by tiny particles,the surface of the hydroxyapatite bioceramic particles was dense and smooth,and the biomimetically precipitated nanocrystalline calcium phosphate granules were mainly composed of needle/plate crystals with non-uniform nanometer size,and formed a nanopore structure between the crystals.X-ray diffraction and Fourier transform infrared spectroscopy exhibited that compared with hydroxyapatite bioceramic granules,biomimetically precipitated nanocrystalline calcium phosphate granules had smaller crystalline particles,lower crystallinity,and more binding water and carbonic acid groups.Compared with hydroxyapatite bioceramic granules,biomimetically precipitated nanocrystalline calcium phosphate granules had higher specific surface area,better hydrophilicity,lower hardness,and higher protein adsorption capacity.(2)The results of MTT assay showed that the two kinds of granule extracts had no cytotoxicity,human umbilical cord mesenchymal stem cells survived well on the surface of the two kinds of granules,and the biomimetically precipitated nanocrystalline calcium phosphate granules had stronger cell proliferation activity.(3)These findings indicate that compared with hydroxyapatite bioceramic granules,biomimetically precipitated nanocrystalline calcium phosphate granules have better physicochemical properties and cytocompatibility.

Application of strontium polyphosphate with both radiopaque and osteogenic functions in calcium phosphate cement / 中国组织工程研究

BACKGROUND:Our previous studies found that adding barium sulfate could improve the mechanical and radiopaque properties of calcium phosphate cement.However,with the degradation of calcium phosphate,the remaining radiopaque agent is difficult to degrade,and the space-occupying and osteoclast effects at the implantation site affect the bone repair process.Therefore,it is necessary to develop a new biodegradable radiopaque material. OBJECTIVE:To discuss the radiopaque ability of bioactive degradable material strontium polyphosphate(SrPP)and its impact on the physicochemical properties and osteogenic effect of calcium phosphate cement. METHODS:(1)Calcium phosphate cement(CPC),starch modified calcium phosphate cement(CPS)and starch modified calcium phosphate cement(20%SrPP-CPN)containing SrPP(20%mass fraction of bone cement powder)were prepared respectively,and the physicochemical properties of the three groups of bone cements were characterized.(2)The three groups of bone cement extracts were co-cultured with rat bone marrow mesenchymal stem cells,respectively,to detect cell proliferation,energy metabolism,and osteogenic differentiation.(3)Bone defects with a diameter of 5 mm were made on each side of the top of the skull of 24 SD rats,and they were randomly divided into control group(without any intervention),CPC group,CPS group,and 20%SrPP-CPN group for intervention,with 6 rats in each group.Relevant tests were performed after 4 and 12 weeks of intervention. RESULTS AND CONCLUSION:(1)Compared with the other two groups of bone cement,20%SrPP-CPN had enhanced radiopaque ability,increased compressive strength and degradation rate,and prolonged curing time,and 20%SrPP-CPN could release Sr2+ stably during degradation.(2)CCK-8 assay showed that 20%SrPP-CPN did not affect the proliferation of bone marrow mesenchymal stem cells.Cell starvation test(serum-free culture)showed that 20%SrPP-CPN could promote the proliferation of bone marrow mesenchymal stem cells compared with the other two groups of bone cement.Compared with the other two groups of bone cements,20%SrPP-CPN increased adenosine triphosphate concentration in bone marrow mesenchymal stem cells.Alkaline phosphatase and alizarin red staining showed that 20%SrPP-CPN could promote osteogenic differentiation of bone marrow mesenchymal stem cells compared with the other two groups of bone cement.(3)In the rat skull defect experiment,Micro-CT scanning and histological observation(hematoxylin-eosin and Masson stainings)showed that bone cement in 20%SrPP-CPN group was significantly degraded compared with that in CPC and CPS groups,and a large number of new bone tissues were dispersed in degraded bone cement.Immunohistochemical staining showed that Runx2 protein expression was increased in 20%SrPP-CPN group compared with CPC group and CPS group(P＜0.01).(4)These results show that 20%SrPP-CPN has good radiopaque ability and osteogenic properties.

Antibacterial magnesium oxide-calcium phosphate composite coating prepared by combining electrodeposition and sol-gel impregnation / 中国组织工程研究

BACKGROUND:Calcium phosphate(CaP)coatings are widely used to improve the integration of titanium implants into bone but these coatings are associated with risks of infection.It is thus desirable to confer antibacterial properties to CaP coatings. OBJECTIVE:To prepare CaP-MgO composite coatings by impregnating magnesium oxide(MgO)sol into CaP coatings and assess the in vitro antibacterial activities and cytocompatibility. METHODS:An electrolyte was determined by titration and used for CaP coating electrodeposition on titanium(referred to as Ti-CaP).MgO was impregnated into the coating by immersing in an MgO sol with different mass fractions(15%,30%,50%)and subsequently calcined to form MgO-CaP composite coatings,which were recorded as Ti-CaP-15Mg,Ti-CaP-30Mg and Ti-CaP-50Mg,respectively.Microstructure,tensile properties,critical load,and Mg2+ release of coatings in vitro were characterized.Antibacterial activity was assayed using spread plate method by culturing S.aureus on the pure titanium sheet surface and Ti-CaP,Ti-Cap-15mg,Ti-Cap-30mg and Ti-Cap-50mg surfaces for 24 and 48 hours.Mouse osteoblast suspension was inoculated on pure titanium sheets and Ti-CaP,Ti-CaP-15Mg,Ti-CaP-30Mg and Ti-CaP-50Mg coated titanium sheets,respectively.Cell proliferation was detected by CCK-8 assay,and cell survival rate was calculated.The morphology of composite coating soaked in DMEM was also observed. RESULTS AND CONCLUSION:(1)Homogeneous,microporous CaP coatings consisting of octacaclium phosphate crystal flakes were prepared on titanium by electrodeposition.After sol impregnation-calcination,MgO aggregates were filled into the inter-flake voids.The extent of MgO filling and Mg concentration in the coating increased with the number of sol impregnation procedures.When immersed in phosphate buffered saline,all composite coatings actively released Mg2+ within 1 day;subsequently,the Mg2+ release slowed down on day 3.A small amount of Mg2+ release was still detected on day 7.The yield strength,tensile strength and fracture growth rate of Ti-CaP-30Mg coated titanium were not significantly different from those of pure titanium(P>0.05).There was no significant difference in the critical load of Ti-CaP,Ti-CaP-15Mg,Ti-CaP-30Mg and Ti-CaP-50Mg groups(P>0.05).(2)Except that pure titanium sheet and Ti-CaP had no antibacterial properties,the other samples had good antibacterial properties,and the antibacterial rate increased with the increase of MgO content in the coating.(3)After 1 and 3 days of co-culture,the cell survival rate of Ti-CaP-15Mg,Ti-CaP-30Mg and Ti-CaP-50Mg groups was lower than that of pure titanium group and Ti-CaP group(P<0.05).After 5 and 7 days of culture,there was no significant difference in cell survival rate among five groups(P>0.05).The content of MgO in the coating decreased gradually with the time of immersion in the medium.(4)The MgO sol impregnation added antibacterial properties to the CaP coatings while retained their biocompatibility.

A case of temporomandibular joint dislocation caused by rosuvastatin calcium tablets / 药物流行病学杂志

A 50-year-old female presented with bilateral cervical arteriosclerosis and right-sided plaque formation,after 25 d of treatment with rosuvastatin calcium tablets(20 mg,po,qn),the patient developed temporomandibular joint dislocation,the adverse reactions occurred again after giving manipulative repositioning.The patients were healthy,had no history of trauma and related diseases in stomatology,no history of drug allergy,patients did not open their mouth loudly at the onset of the disease,no external factors affecting the use of drugs during the combined use of other drugs.It was considered"very likely"that the dislocation of the jaw joint was caused by rosuvastatin calcium tablets.The patients were followed up for 3 months after the treatment of manipulative repositioning and other treatments,did not have any further dislocation of the temporomandibular joint dislocation.It is suggested that when using rosuvastatin calcium in clinical practice,attention should be paid to strengthening drug observation to ensure drug safety.

Mechanism of Piezo1 channel activation promoting increase in intracellu-lar calcium concentration of rat coronary smooth muscle cells / 中国病理生理杂志

AIM:To investigate the mechanism of Piezo1 channel activation promoting the increase in intra-cellular Ca2+ concentration([Ca2+]i)of rat coronary artery smooth muscle cells(CASMCs).METHODS:The primary CASMCs of SD rats were cultured,and the expression and subcellular localization of Piezo1 in the cells were observed by immunofluorescence staining.The Piezo1 and stromal interaction molecule 1(STIM1)in CASMCs were knocked down by siRNA transfection,and the expression levels of the proteins were detected by Western blot.Utilizing laser confocal mi-croscopy,the change of[Ca2+]i in CASMCs was detected by Fluo-4 AM fluorescent probes.RESULTS:It was confirmed by immunofluorescence staining that the expression of Piezo1 existed in primary rat CASMCs.Immunofluorescence staining also showed that Piezo1 was co-located with sarco-/endoplasmic reticulum Ca2+-ATPase 2(SERCA2),mitochondrial outer membrane protein TOM20 and nuclear membrane protein lamin B1.Western blot results showed that the protein expres-sion levels of STIM1 and Piezo1 were significantly down-regulated by siRNA transfection(P<0.05).Compared with con-trol group,Yoda1,the agonist of Piezo1,could increase the extracellular Ca2+ influx of CASMCs(P<0.01).However,the Ca2+ influx mediated by Yoda1 was not affected by the inhibition of L-type calcium channels.Treatment with Yoda1 in-creased the intracellular Ca2+ release of CASMCs(P<0.01).However,inhibition of calcium channels on endoplasmic re-ticulum,ryanodine receptor and inositol 1,4,5-triphosphate receptor,did not affect intracellular Ca2+ release mediated by Yoda1.After the Ca2+ in endoplasmic reticulum was emptied using thapsigargin(TG),Yoda1 also mediated the Ca2+ re-lease of other organelles in CASMCs(P<0.01).After inhibition of L-type calcium channels,treatment with store-operated calcium channel(SOCC)inhibitor BTP2 or knockdown of STIM1 led to the decrease in extracellular Ca2+ influx of CASMCs mediated by Yoda1(P<0.01).Treatment with TG increased the release of Ca2+ from the endoplasmic reticulum of CASMCs after knockdown of Piezo1(P<0.05),but the extracellular Ca2+ influx mediated by TG was not affected.After inhibition of L-type calcium channels and SOCC,knockdown of Piezo1 led to the decreases in intracellular Ca2+ release and extracellular Ca2+ influx induced by Yoda1(P<0.01).CONCLUSION:The Piezo1 agonist orchestrates the influx of extracellular Ca2+ by activating Piezo1 channels on the cell membrane and inducing the indirect activation of SOCC.More-over,it facilitates the release of Ca2+ from organelles.Consequently,these pathways synergistically elevate the[Ca2+]i of rat CASMCs.