Microalgae Biomass Production from Rice Husk as Alternative Media Cultivation and Extraction of Phycocyanin Using 3D-Printed Ohmic Heating Reactor.

Phycocyanin is a highly valued pigment present in Spirulina platensis biomass with applications in the food industry in terms of biorefinery concepts; specifically, its antioxidant and antimicrobial capacity are an advantage that could be incorporated into a food matrix. This study aims to use rice husk as an alternative culture medium for S. platensis biomass growth and phycocyanin extraction by ohmic heating processing using a 3D-printed reactor. S. platensis was cultivated in rice husk extract (RHE) from 0-100% (v/v). The highest content of microalgal biomass was 1.75 ± 0.01 g/L, with a specific growth rate of 0.125 ± 0.01 h-1. For the phycocyanin extraction under an ohmic heating process, a 3D-printed reactor was designed and built. To optimize phycocyanin extraction, a central composite rotatable design (CCDR) was evaluated, with three factors: time (min), temperature (°C), and pH. The highest phycocyanin content was 75.80 ± 0.98 mg/g in S. platensis biomass grown with rice husk extract. Ohmic heating is a promising method for rapid phycocyanin extraction, and rice husk as a culture medium is an alternative for the growth of S. platensis biomass in the integration of second- and third-generation biorefineries.

The Urgent Need for Neuroscience Research to Consider Culture when Assessing the Development of Gait in Autistic Children: A Scoping Review.

BACKGROUND: Over the last decade, there has been a steady increase in the number of children diagnosed with autism spectrum disorder (ASD) on a global scale, impacting all racial and cultural groups. This increase in the diagnostic rate has prompted investigation into a myriad of factors that may serve as early signs of ASD. One of these factors includes the biomechanics of gait, or the manner of walking. Although ASD is a spectrum, many autistic children experience differences in gross motor function, including gait. It has been documented that gait is also impacted by racial and cultural background. Given that ASD is equally prevalent across all cultural backgrounds, it is urgent that studies assessing gait in autistic children consider the impact of cultural factors on children's development of gait. The purpose of the present scoping review was to assess whether recent empirical research studies focusing on gait in autistic children have taken culture into account. METHODS: To do so, we conducted a scoping review following PRISMA guidelines using a keyword searching with the terms autism, OR autism spectrum disorder, OR ASD, OR autis, AND gait OR walking in the following databases: CINAHL, ERIC (EBSCO), Medline, ProQuest Nursing & Allied Health Source, PsychInfo, PubMed, and Scopus. Articles were considered for review if they met all six of the following inclusionary criteria: (1) included participants with a diagnosis of autism spectrum disorder (ASD), (2) directly measured gait or walking, (3) the article was a primary study, (4) the article was written in English, (5) participants included children up to age 18, and (6) the article was published between 2014 and 2022. RESULTS: A total of 43 articles met eligibility criteria but none of the articles took culture into account in the data analysis process. CONCLUSIONS: There is an urgent need for neuroscience research to consider cultural factors when assessing gait characteristics of autistic children. This would allow for more culturally responsive and equitable assessment and intervention planning for all autistic children.

Carotid artery stenting has similar outcomes in men and women.

BACKGROUND: The aim of carotid interventions is to prevent cerebrovascular events. Endovascular treatment (carotid-artery-stenting/CAS) has become established as an alternative to open surgery in some cases. Historically, female sex has been considered as a perioperative risk factor, however, there are few studies regarding this hypothesis when it comes to CAS. OBJECTIVES: To analyze the CAS results in our center adjusted by sex. METHODS: A retrospective cohort study was designed, including patients with carotid atheromatosis operated at a single center from January 2016 to June 2019. Our objective was to compare cardiovascular risk, including myocardial infarction, stroke, and mortality, by sex. Follow-up rates of stent patency, restenosis, stroke, myocardial infarction, and death were reported. RESULTS: 71 interventions were performed in 50 men (70.42%) and 21 women (29.57%). Mean age was 70.50 ± 10.72 years for men and 73.62 ± 11.78 years for women. Cardiovascular risk factors did not differ significantly between sexes. Mean follow-up was 11.28 ± 11.28 months. There were no significant differences in neurological events during follow-up. No adverse cardiological events were detected at any time. Regarding the mortality rate, during medium-term follow up there were 2 neurological related deaths with no significant differences between sexes (p=0.8432). Neither sex had higher rated of restenosis during long term follow-up (5.63% vs. 1.41%, p = 0.9693) or reoperation (1.41% vs. 1.41%, p = 0.4971). All procedures remained patent (<50% restenosis). CONCLUSIONS: Despite the limitations of our study, CAS is a therapeutic option that is as effective and safe in women as in men. No sex differences were observed.

CONTEXTO: As intervenções carotídeas visam prevenir eventos cerebrovasculares. O tratamento endovascular (implante de stent na artéria carótida) se estabeleceu como uma alternativa à cirurgia aberta em alguns casos. Historicamente, o sexo feminino é considerado um fator de risco perioperatório, mas há poucos estudos abordando essa hipótese em casos de stent de carótida. OBJETIVOS: Analisar os resultados do CAS em nosso centro ajustados por sexo. MÉTODOS: Este estudo de coorte retrospectivo incluiu pacientes com ateromatose carotídea operados em um centro de janeiro de 2016 a junho de 2019. Nosso objetivo foi comparar o risco cardiovascular, incluindo infarto do miocárdio, acidente vascular cerebral e mortalidade, de acordo com o sexo. No seguimento, foram descritos patência do stent, reestenose, acidente vascular cerebral, infarto do miocárdio e morte. RESULTADOS: Setenta e uma intervenções foram realizadas: 50 homens (70,42%) e 21 mulheres (29,57%). A média de idade foi de 70,50 ± 10,72 anos nos homens e 73,62 ± 11,78 anos nas mulheres. Os fatores de risco cardiovascular não diferiram significativamente entre os sexos. A média de seguimento foi de 11,28 ± 11,28 meses. Durante o seguimento, não houve diferenças significativas nos eventos neurológicos. Nenhum evento cardiológico adverso foi detectado. Quanto à taxa de mortalidade, durante o seguimento de médio prazo ocorreram 2 óbitos neurológicos sem diferenças significativas entre os sexos (p = 0,8432). Não foi observada maior taxa de reestenose no seguimento de longo prazo (5,63% vs. 1,41%, p = 0,9693) ou de reoperação (1,41% vs. 1,41%, p = 0,4971) ao comparar os dois sexos. Todos os procedimentos permaneceram pérvios (< 50% de reestenose). CONCLUSÕES: Apesar das limitações deste estudo, o stent de carótida em mulheres é uma opção terapêutica tão eficaz e segura quanto em homens. Nenhuma diferença foi observada entre os sexos.

Mortality of COVID-19 patients with vascular thrombotic complications.

PURPOSE: To analyze the survival of patients hospitalized with COVID-19 and who presented some vascular thrombotic complication. MATERIAL AND METHODS: All consecutive patients with COVID-19 who were treated during the months of March and April 2020 at our institution were included. All patients were symptomatic and the thrombotic event objectively confirmed. Patients with deep vein thrombosis (DVT), pulmonary embolism (PE), ischemic stroke, and peripheral arterial thrombosis (PAT) were included. Survival curves for all groups were analyzed using Kaplan-Meier with Log Rank test, and Cox regression. RESULTS: During the pandemic period from March-1 to April-30, 2943 patients were treated with confirmed COVID-19 in our center. 106 patients showed some symptomatic vascular thrombosis: 13 patients had PAT, 15 ischemic stroke, 20 DVT and 58 PE. 11 patients presented multiple vascular thrombosis. Although the mean age was 65 years, there were differences between groups being older those patients with arterial thrombosis. A 67.92% were men. In total, 25 patients died during their hospital admission (23.58%), with differences between groups, being more common in patients with PAT (9 patients out of 13) and ischemic stroke (8 patients out of 15), than in those with DVT (1 patient out of 20) or PE (7 patients out of 58). CONCLUSIONS: The venous thromboembolic risk in these patients is greater than the arterial, but arterial thrombosis when it occurs was associated with high mortality rates. Survival was better in patients with DVT and PE than in patients with ischemic stroke or PAT.

OBJETIVO: Presentar nuestra experiencia y analizar la supervivencia de los pacientes hospitalizados con COVID-19 y que presentaron algún proceso trombótico vascular. MATERIAL Y MÉTODOS: Se incluyeron todos los pacientes consecutivos COVID-19 que fueron atendidos durante los meses de marzo-abril 2020 en nuestra institución. Se incluyeron pacientes sintomáticos con trombosis venosa profunda (TVP), tromboembolia pulmonar (TEP), ictus isquémico y trombosis arterial periférica (TAP) confirmados objetivamente. Se analizaron las curvas de supervivencia de todos los grupos mediante Kaplan-Meier, test de Log Rank, y regresión de Cox. RESULTADOS: Durante el periodo pandémico del 1-marzo al 30-abril, se atendieron 2943 pacientes COVID-19 en nuestro centro. 106 pacientes presentaron algún proceso trombótico vascular sintomático: 13 pacientes tuvieron TAP, 15 ictus, 20 TVP y 58 TEP. 11 pacientes mostraron trombosis vasculares múltiples. Aunque la edad media fue de 65 años, fueron de edad más avanzada los que mostraron trombosis arteriales que procesos tromboembólicos venosos. El 67.92% fueron hombres. En total, 25 pacientes murieron durante su ingreso hospitalario (23.58%), existiendo diferencias entre grupos siendo más común en pacientes con TAP (9 pacientes de 13), e ictus isquémico (8 pacientes de 15), que en los de TVP (1 paciente de 20) o TEP (7 pacientes de 58). CONCLUSIONES: El riesgo tromboembólico venoso en estos pacientes es mayor que el arterial, pero la trombosis arterial cuando acontece estuvo asociada a altas tasas de mortalidad. La supervivencia fue mejor en los pacientes con TVP y TEP que en los pacientes con ictus isquémico o trombosis arterial periférica.

Mortalidad de los pacientes covid-19 con complicaciones trombóticas / Mortality of covid-19 patients with vascular thrombotic complications

Objetivo: Presentar nuestra experiencia y analizar la supervivencia de los pacientes hospitalizados con covid-19 y que desarrollaron algún proceso trombótico vascular.Material y métodosSe incluyó a todos los pacientes consecutivos con covid-19 que fueron atendidos durante los meses de marzo y abril de 2020 en nuestra institución. Se incluyó a pacientes sintomáticos con trombosis venosa profunda (TVP), tromboembolia pulmonar (TEP), ictus isquémico y trombosis arterial periférica (TAP) confirmados objetivamente. Se analizaron las curvas de supervivencia de todos los grupos mediante Kaplan-Meier, test de log rank y regresión de Cox.ResultadosDurante el periodo pandémico del 1 de marzo al 30 de abril, fueron atendidos 2.943 pacientes con covid-19 en nuestro centro. De ellos, 106 presentaron algún proceso trombótico vascular sintomático: 13 pacientes tuvieron TAP, 15 ictus, 20 TVP y 58 TEP; otros 11 pacientes mostraron trombosis vasculares múltiples. Aunque la edad media fue de 65 años, fueron de edad más avanzada los que mostraron trombosis arteriales que los que mostraron procesos tromboembólicos venosos. El 67,92% fueron hombres. En total, 25 pacientes murieron durante su ingreso hospitalario (23,58%), con diferencias entre grupos: fue más común en pacientes con TAP (9 pacientes de 13) e ictus isquémico (8 pacientes de 15), que en los de TVP (1 paciente de 20) o TEP (7 pacientes de 58).ConclusionesEl riesgo tromboembólico venoso en estos pacientes es mayor que el arterial, pero la trombosis arterial cuando aconteció estuvo asociada a altas tasas de mortalidad. La supervivencia fue mejor en los pacientes con TVP y TEP que en los pacientes con ictus isquémico o TAP. (AU)

Objective: To analyze the survival of patients hospitalized with covid-19 and who presented some vascular thrombotic complication.Material and methodsAll consecutive patients with covid-19 who were treated during the months of March and April 2020 at our institution were included. All patients were symptomatic and the thrombotic event objectively confirmed. Patients with deep vein thrombosis (DVT), pulmonary embolism (PE), ischemic stroke, and peripheral arterial thrombosis (PAT) were included. Survival curves for all groups were analyzed using Kaplan-Meier with log rank test, and Cox regression.ResultsDuring the pandemic period from March-1 to April-30, 2943 patients were treated with confirmed covid-19 in our center. Of them, 106 patients showed some symptomatic vascular thrombosis: 13 patients had PAT, 15 ischemic stroke, 20 DVT and 58 PE. Another 11 patients presented multiple vascular thrombosis. Although the mean age was 65 years, there were differences between groups being older those patients with arterial thrombosis. A 67.92% were men. In total, 25 patients died during their hospital admission (23.58%), with differences between groups, being more common in patients with PAT (9 patients out of 13) and ischemic stroke (8 patients out of 15), than in those with DVT (1 patient out of 20) or PE (7 patients out of 58).ConclusionsThe venous thromboembolic risk in these patients is greater than the arterial, but arterial thrombosis when it occurs was associated with high mortality rates. Survival was better in patients with DVT and PE than in patients with ischemic stroke or PAT. (AU)

[Mortality of covid-19 patients with vascular thrombotic complications]. / Mortalidad de los pacientes covid-19 con complicaciones trombóticas.

OBJECTIVE: To analyze the survival of patients hospitalized with covid-19 and who presented some vascular thrombotic complication. MATERIAL AND METHODS: All consecutive patients with covid-19 who were treated during the months of March and April 2020 at our institution were included. All patients were symptomatic and the thrombotic event objectively confirmed. Patients with deep vein thrombosis (DVT), pulmonary embolism (PE), ischemic stroke, and peripheral arterial thrombosis (PAT) were included. Survival curves for all groups were analyzed using Kaplan-Meier with log rank test, and Cox regression. RESULTS: During the pandemic period from March-1 to April-30, 2943 patients were treated with confirmed covid-19 in our center. Of them, 106 patients showed some symptomatic vascular thrombosis: 13 patients had PAT, 15 ischemic stroke, 20 DVT and 58 PE. Another 11 patients presented multiple vascular thrombosis. Although the mean age was 65 years, there were differences between groups being older those patients with arterial thrombosis. A 67.92% were men. In total, 25 patients died during their hospital admission (23.58%), with differences between groups, being more common in patients with PAT (9 patients out of 13) and ischemic stroke (8 patients out of 15), than in those with DVT (1 patient out of 20) or PE (7 patients out of 58). CONCLUSIONS: The venous thromboembolic risk in these patients is greater than the arterial, but arterial thrombosis when it occurs was associated with high mortality rates. Survival was better in patients with DVT and PE than in patients with ischemic stroke or PAT.

Carotid artery stenting has similar outcomes in men and women / Implante de stent na artéria carótida tem desfechos semelhantes em homens e mulheres

Abstract Background The aim of carotid interventions is to prevent cerebrovascular events. Endovascular treatment (carotid-artery-stenting/CAS) has become established as an alternative to open surgery in some cases. Historically, female sex has been considered as a perioperative risk factor, however, there are few studies regarding this hypothesis when it comes to CAS. Objectives To analyze the CAS results in our center adjusted by sex. Methods A retrospective cohort study was designed, including patients with carotid atheromatosis operated at a single center from January 2016 to June 2019. Our objective was to compare cardiovascular risk, including myocardial infarction, stroke, and mortality, by sex. Follow-up rates of stent patency, restenosis, stroke, myocardial infarction, and death were reported. Results 71 interventions were performed in 50 men (70.42%) and 21 women (29.57%). Mean age was 70.50 ± 10.72 years for men and 73.62 ± 11.78 years for women. Cardiovascular risk factors did not differ significantly between sexes. Mean follow-up was 11.28 ± 11.28 months. There were no significant differences in neurological events during follow-up. No adverse cardiological events were detected at any time. Regarding the mortality rate, during medium-term follow up there were 2 neurological related deaths with no significant differences between sexes (p=0.8432). Neither sex had higher rated of restenosis during long term follow-up (5.63% vs. 1.41%, p = 0.9693) or reoperation (1.41% vs. 1.41%, p = 0.4971). All procedures remained patent (<50% restenosis). Conclusions Despite the limitations of our study, CAS is a therapeutic option that is as effective and safe in women as in men. No sex differences were observed.

Resumo Contexto As intervenções carotídeas visam prevenir eventos cerebrovasculares. O tratamento endovascular (implante de stent na artéria carótida) se estabeleceu como uma alternativa à cirurgia aberta em alguns casos. Historicamente, o sexo feminino é considerado um fator de risco perioperatório, mas há poucos estudos abordando essa hipótese em casos de stent de carótida. Objetivos Analisar os resultados do CAS em nosso centro ajustados por sexo. Métodos Este estudo de coorte retrospectivo incluiu pacientes com ateromatose carotídea operados em um centro de janeiro de 2016 a junho de 2019. Nosso objetivo foi comparar o risco cardiovascular, incluindo infarto do miocárdio, acidente vascular cerebral e mortalidade, de acordo com o sexo. No seguimento, foram descritos patência do stent, reestenose, acidente vascular cerebral, infarto do miocárdio e morte. Resultados Setenta e uma intervenções foram realizadas: 50 homens (70,42%) e 21 mulheres (29,57%). A média de idade foi de 70,50 ± 10,72 anos nos homens e 73,62 ± 11,78 anos nas mulheres. Os fatores de risco cardiovascular não diferiram significativamente entre os sexos. A média de seguimento foi de 11,28 ± 11,28 meses. Durante o seguimento, não houve diferenças significativas nos eventos neurológicos. Nenhum evento cardiológico adverso foi detectado. Quanto à taxa de mortalidade, durante o seguimento de médio prazo ocorreram 2 óbitos neurológicos sem diferenças significativas entre os sexos (p = 0,8432). Não foi observada maior taxa de reestenose no seguimento de longo prazo (5,63% vs. 1,41%, p = 0,9693) ou de reoperação (1,41% vs. 1,41%, p = 0,4971) ao comparar os dois sexos. Todos os procedimentos permaneceram pérvios (< 50% de reestenose). Conclusões Apesar das limitações deste estudo, o stent de carótida em mulheres é uma opção terapêutica tão eficaz e segura quanto em homens. Nenhuma diferença foi observada entre os sexos.

A Photoactivatable Formaldehyde Donor with Fluorescence Monitoring Reveals Threshold To Arrest Cell Migration.

Controlled light-mediated delivery of biological analytes can enable the investigation of highly reactivity molecules within living systems. As many biological effects are concentration dependent, it is critical to determine the location, time, and quantity of analyte donation. In this work, we have developed the first photoactivatable donor for formaldehyde (FA). Our optimized photoactivatable donor, photoFAD-3, is equipped with a fluorescence readout that enables monitoring of FA release with a concomitant 139-fold fluorescence enhancement. Tuning of photostability and cellular retention enabled quantification of intracellular FA release through cell lysate calibration. Application of photoFAD-3 uncovered the concentration range necessary for arresting wound healing in live cells. This marks the first report where a photoactivatable donor for any analyte has been used to quantify intracellular release.

Peanut Allergy in Spanish Children: Comparative Profile of Peanut Allergy versus Tolerance.

BACKGROUND: Peanut storage proteins (Ara h 1, Ara h 2, and Ara h 3) have been described as the major peanut allergens in children, although not all peanut-sensitized individuals have clinical reactivity after exposure. OBJECTIVES: We studied the sensitization profile of peanut-allergic and peanut-tolerant children in a pediatric cohort. METHODS: The clinical features and sensitization profile to the peanut storage proteins Ara h 9 and Pru p 3 were compared between peanut-allergic and peanut-tolerant children using component-resolved diagnostics. RESULTS: Thirty-three peanut-sensitized children were included: 22 allergic and 11 tolerant patients. Seventy-two percent of the peanut-allergic children were sensitized to at least one peanut storage protein. The rates of sensitization to Ara h 1, Ara h 2, and Ara h 3 were 63.6, 68.1, and 68.1%, respectively, among the peanut-allergic children and 27.2, 18.1, and 45.4% among the peanut-tolerant children. IgE from the sera of 18% of the peanut-allergic patients recognized Ara h 9, whereas no sensitization to Ara h 9 was detected in the peanut-tolerant children. A total of 59% of the peanut-allergic and 27% of the peanut-tolerant children were sensitized to Pru p 3. Sensitization to Ara h 1 and Ara h 2 was more frequent among the peanut-allergic children (p < 0.05). Although the levels of specific IgE against peanut storage proteins were higher in peanut allergy, there were not statistically significantly different from the levels in peanut tolerance, probably due to the small number of patients included. CONCLUSIONS: In our population, the peanut-allergic children were mainly sensitized to peanut storage proteins, and Ara h 2 sensitization allows a more accurate diagnosis of clinical reactivity to peanuts. More than half of the peanut-allergic patients were sensitized to peach Pru p 3, and 50% of them had fruit allergy at the time of the study.

Atrial Fibrillation in Anaphylaxis.

BACKGROUND: The relationship between anaphylaxis and cardiovascular events has been reported in the past. While skin and respiratory symptoms are usually the most common and the first to appear, cardiovascular complications play a key role and represent the leading cause of death in anaphylaxis. METHODS: We report 3 episodes of atrial fibrillation triggered by anaphylaxis. Allergy and cardiology studies were performed. In both patients, the etiological agent was identified: Anisakis simplex hypersensitivity and food allergy. RESULTS: The heart is the source and target of chemical mediators released during an allergic reaction. In the heart, there are plenty of mast cells, and they are predominantly located around the coronary adventitia and in close contact with small vessels in the muscle wall. The release of mediators can influence ventricular function, heart rate, and coronary artery tone. Anaphylaxis can trigger any kind of arrhythmia. In these cases, the very interesting point of discussion was: which should be first, treating anaphylaxis or cardiac events? The other controversial point was the use of epinephrine, the first line of treatment for anaphylaxis. Recommendations about epinephrine in cardiac patients during an anaphylactic event are still a major dilemma. CONCLUSIONS: We emphasize the importance of the priority of establishing protocols between cardiologist and allergist in treatment of cardiac complications during anaphylaxis, and we warn about the correct diagnosis of arrhythmias in anaphylaxis in order to treat them as soon as possible, to prevent other consequences and complications.

Caries de la infancia temprana: ¿negligencia o ignorancia?: reporte de un caso / Early childhood caries: ¿neglect or ignorance?: report of a case

El presente es el reporte de un caso de un niño de 5 años 4 meses de edad que exhibía un patrón de caries dental de la infancia temprana severa no tratada oportunamente, debido a ignorancia y posible negligencia por parte de los padres. Se describe el proceso diagnóstico y el tratamiento brindado al paciente y el manejo preventivo que se instituyó a corto, mediano y largo plazo.

This case report is of a 5 years 4 months old male patient who exhibited a pattern of severe dental early caries childhood not treated in a timely manner, due to parent ignorance and possible negligence. The diagnostic process, treatment provided to the patient, and instituted preventive management in the short, medium and long term, are described.

Microleakage of porcelain veneer restorations bonded to enamel and dentin with a new self-adhesive resin-based dental cement.

UNLABELLED: Cementation technique of bonded ceramic restorations is a time-consuming and technique-sensitive procedure critical to long-term success. OBJECTIVE: Evaluate the performance of a self-adhesive, modified-resin dental cement (Rely-X UniCem, 3M-ESPE) for the cementation of ceramic veneer restorations without previous conditioning of the tooth surface, and in combination with a one-bottle adhesive and a self-etching adhesive. METHODS: Thirty-six premolars received a veneer preparation that extended into dentin. Leucite-reinforced pressed glass ceramic (Empress 1) veneers were cemented following manufacturers' instructions, according to the following treatment groups (n=9): (1) Variolink-Excite Ivoclar-Vivadent (V+E control), (2) Unicem+Single Bond 3M-ESPE (U+SB), (3) Unicem+Adper Prompt L-Pop 3M-ESPE (U+AP), (4) Unicem 3M-ESPE (U). After 24h storage at 37 degrees C, teeth were thermocycled (2000 cycles) at 5 and 55 degrees C, immersed in ammoniacal silver nitrate for 24h, placed in a developer solution overnight and sectioned using a slow-speed saw. Three 1mm longitudinal sections were obtained from each tooth and evaluated for leakage with a microscope (1x to 4x). Imaging software was used to measure stain penetration along the dentin and enamel surfaces. RESULTS: ANOVA with SNK (alpha=0.05) revealed that on dentin, U had significantly less leakage than U+SB and U+AP, but no different than V+E; on enamel U had leakage values that were significantly greater than the groups with adhesives. SIGNIFICANCE: The self-adhesive cement U gave low leakage on dentin that was comparable to the cement that employed an adhesive for sealing dentin, whereas this cement benefits from use of an adhesive when cementing to enamel.

Interfacial and surface characterization of two self-etching adhesive systems and a total-etch adhesive after bonding to ground and unground bovine enamel--a qualitative study.

The purpose of the study was to evaluate the enamel surface and interface morphology of two self-etching adhesive systems (SAS) vs a total-etch control, after bonding to ground and unground enamel using field emission scanning electron microscopy (FESEM). Thirty bovine incisors were used in this study. The buccal enamel surface of 15 teeth was ground flat to resemble freshly cut enamel. The rest of the teeth were left intact. Two SAS, Clearfil SE Bond (CSE, Kuraray) and Prompt L-Pop (3M-ESPE), and a conventional adhesive system, Scotchbond Multipurpose (3M-ESPE, control), were used to condition the surface of unground and ground enamel on 12 teeth. A composite button was bonded to the remaining 18 teeth; a cross-section (1 mm thick) was obtained from each and the bonded interface was polished. All specimens were dehydrated in ascending grades of ethanol, gold-sputter-coated, and observed under FESEM (Hitachi S-4000) to evaluate the ultrastructural morphology of the enamel surface and the enamel-dentin interface. The etching patterns and adhesive penetration varied according to the aggressiveness of the SAS, with CSE being the mildest and H3PO4 being the most aggressive. There were no significant differences on the ultrastructural morphology of the enamel surface between unground and ground specimens. It appears that microporosities within enamel prisms provide sufficient enamel-resin hybridization in unground enamel. The enamel dissolution pattern and depth of infiltration depend on the type of SAS used, with no significant differences in unground and ground enamel.

Effects of gray and white mineral trioxide aggregate on the proliferation of oral keratinocytes and cementoblasts.

Mineral trioxide aggregate (MTA) is used as a repair material and may directly contact cells from different cell lineages. The purpose of this study was to assess cell proliferation of immortalized Murine cementoblasts (OCCM.30) and immortalized keratinocytes (OKF6/TERT1) on gray MTA (GMTA) and white MTA (WMTA) with the DNA intercalating dye Hoechst 33342. Cells were grown for 72 hours on GMTA or WMTA that had been cured for 24 hours or 12 days. WMTA significantly (p < 0.001) increased the proliferation of OCCM.30 cementoblasts compared to control and OKF6/TERT1 keratinocytes. Both cell types grew significantly (p < 0.001) better on the surface of WMTA compared to GMTA. In addition, both cell types showed significantly (p < 0.005) higher proliferation when grown on 12-day-cured GMTA compared to 24-hour-cured GMTA.

Microtensile bond strength of self-etching adhesives to ground and unground enamel.

PURPOSE: The purpose of this study was to assess the bond strength of two self-etching primers (SEP) to ground and unground enamel. MATERIALS AND METHODS: Seventy-two bovine incisors were used in this study. The buccal enamel surface of 36 teeth was ground flat to resemble freshly cut enamel. The rest of the teeth were left intact. Two SEPs--Clearfil SE Bond, Kuraray (CSE) and Prompt L-Pop (3M ESPE) (LP)--and a conventional adhesive system, Scotchbond Multi-Purpose (3M ESPE) (SBMP) as a control, were used to bond a composite button to prepared and unprepared enamel. Microtensile test specimens were trimmed, resulting in a cylindrical cross-sectional area (0.21 mm2 to 0.47 mm2). These specimens were subjected to a tensile force at 1 mm/min until failure. Differences between adhesives and surface preparation were determined by two-way ANOVA. The samples were observed under SEM to evaluate the mode of failure. RESULTS: Bond strength values in MPa (SD) obtained from pooled data in descending order were: SBMP ground 44.54 (5.96), LP unground 42.97 (7.90), CSE unground 41.67 (11.28), LP ground 41.07 (12.07), CSE ground 38.56 (8.78), and SBMP unground 37.60 (9.55). No statistically significant differences were found (p = 0.5061) between surface preparation or adhesive systems. The mean in MPa (SD) of all the specimens that failed at the adhesive joint were: LP unground 47.13 (14.65), SBMP ground 45.28 (7.33), CSE unground 41.40 (11.07), SBMP unground 41.1 (10.04), CSE ground 39.96 (11.83), and LP ground 39.92 (15.45). No statistically significant differences were found (p = 0.5863). Failure occurred mainly at the adhesive interface. CONCLUSIONS: Surface preparation and adhesive treatment had no influence on resin composite microtensile bond strength to bovine enamel.