Synergistic effects of Tb doping in long-persistent luminescence in Ca3Ga4O9: xBi3+, yZn2+ phosphors: Implications for novel phosphorescent materials.

Long afterglow phosphors constitute an emerging class of compounds with wide application in several fields, from photonic to dosimetry, solar energy storage and photocatalysis. In this study, we synthesized and thoroughly characterized a new class of persistent emitting materials, Ca3Ga4O9: xBi3+, yZn2+, zTb3+. Through the utilization of X-ray and Raman spectroscopy, as well as optical measurements including static and time-resolved luminescence, thermoluminescence, and phosphorescence, the effects of the Tb concentration on the optical and structural properties of the material has been deeply studied. A suitable mechanism was proposed to account for the long afterglow emission, wherein Tb3+ and Bi3+ ions occupying the Ca2+ sites serve as recombination centers, facilitating the generation of oxygen defects. Zn2+ in the Ga3+ sites, contribute to the charge balance and generates hole traps in the matrix. The enduring phosphorescence persists for over 3 h following the cessation of UV irradiation, discernible to the naked eye in low-light conditions.

Optimizing the Mechanoluminescent Properties of CaZnOS:Tb via Microwave-Assisted Synthesis: A Comparative Study with Conventional Thermal Methods.

Recent developments in lighting and display technologies have led to an increased focus on materials and phosphors with high efficiency, chemical stability, and eco-friendliness. Mechanoluminescence (ML) is a promising technology for new lighting devices, specifically in pressure sensors and displays. CaZnOS has been identified as an efficient ML material, with potential applications as a stress sensor. This study focuses on optimizing the mechanoluminescent properties of CaZnOS:Tb through microwave-assisted synthesis. We successfully synthesized CaZnOS doped with Tb3+ using this method and compared it with samples obtained through conventional solid-state methods. We analyzed the material's characteristics using various techniques to investigate their structural, morphological, and optical properties. We then studied the material's mechanoluminescent properties through single impacts with varying energies. Our results show that materials synthesized through microwave methods exhibit similar optical and, primarily, mechanoluminescent properties, making them suitable for use in photonics applications. The comparison of the microwave and conventional solid-state synthesis methods highlights the potential of microwave-assisted methods to optimize the properties of mechanoluminescent materials for practical applications.

Design and evaluation of a learning assignment in the undergraduate medical curricula on the four dimensions of care: a mixed method study.

BACKGROUND: Chronic and palliative care are rapidly gaining importance within the physician's range of duties. In this context, it is important to address the four dimensions of care: physical, psychological, social, and spiritual. Medical students, however, feel inadequately equipped to discuss these dimensions with the patient. To bridge this gap, a new assignment was developed and implemented, in which students talked to a chronic or palliative patient about the four dimensions of care during an internship. This study, reports the evaluation of this assignment by students and teachers using a design-based approach. METHODS: Mixed methods were used, including a) student questionnaires, b) student focus groups, c) teacher interviews, and d) student's written reflections. Two researchers performed analyses of the qualitative data from the focus groups, interviews, and written reflections using qualitative research software (ALTLAS.TI). Descriptive statistics were computed for the quantitative data using SPSS 21.0. RESULTS: Students and teachers valued talking to an actual patient about the four dimensions of care. Reading and providing peer feedback on each other's reports was considered valuable, especially when it came to the diversity of illnesses, the way that patients cope and communication techniques. The students considered reflection useful, especially in the group and provided it was not too frequent. All the dimensions were addressed in the interviews, however the spiritual dimension was found to be the most difficult to discuss. The analysis of the written reflections revealed an overlap between the social and spiritual dimensions. Students pay a lot of attention to the relationship between the illness and the patient's daily life, but the reflections do often not show insight in the potential relationship between the four dimensions and decisions in patient care. CONCLUSIONS: During internships, medical students can practice talking about four dimensions of care with a chronically ill or palliative patient. Due to the format, it can be implemented across existing internships with relatively little extra time and effort. Reflection, peer feedback, and group discussion under the guidance of a teacher are important additions.

Biomaterial and Biofilm Interactions with the Pulp-Dentin Complex-on-a-Chip.

Calcium silicate cements (CSCs) are the choice materials for vital pulp therapy because of their bioactive properties, promotion of pulp repair, and dentin bridge formation. Despite the significant progress made in understanding CSCs' mechanisms of action, the key events that characterize the early interplay between CSC-dentin-pulp are still poorly understood. To address this gap, a microfluidic device, the "tooth-on-a-chip," which was developed to emulate the biomaterial-dentin-pulp interface, was used to test 1) the effect of CSCs (ProRoot, Biodentine, and TheraCal) on the viability and proliferation of human dental pulp stem cells, 2) variations of pH, and 3) release within the pulp chamber of transforming growth factor-ß (TGFß) as a surrogate of the bioactive dentin matrix molecules. ProRoot significantly increased the extraction of TGFß (P < 0.05) within 24 to 72 h and, along with Biodentine, induced higher cell proliferation (P > 0.05), while TheraCal decreased cell viability and provoked atypical changes in cell morphology. No correlation between TGFß levels and pH was observed. Further, we established a biofilm of Streptococcus mutans on-chip to model the biomaterial-biofilm-dentin interface and conducted a live and dead assay to test the antimicrobial capability of ProRoot in real time. In conclusion, the device allows for direct characterization of the interaction of bioactive dental materials with the dentin-pulp complex on a model of restored tooth while enabling assessment of antibiofilm properties at the interface in real time that was previously unattainable.

Eugenol as an efficient anesthetic for neotropical fish Prochilodus nigricans (Teleostei, Prochilodontidae) / [Eugenol como um anestésico eficaz para o peixe neotropical Prochilodus nigricans (Teleostei, Prochilodontidae)]

The use of anesthetics in fish farming is essential to reduce stress during management. The present study proposes to evaluate the effect of eugenol as an anesthetic for the management of curimatã (Prochilodus nigricans). Fifty specimens were used (221.34±9.0 g; 25.8 ±1.1 cm), submitted to five treatments with concentrations of 0, 25, 50, 100 and 200 mgL−1 eugenol for 10 min. The times required to reach each anesthetic stage and the recovery of each fish were recorded. To check bloodglucose levels individual blood samples were taken from the fish before immersion and after ten minutes of anesthetic exposure. Evaluation of the anesthetic effect ongills was performed by histopathological analysis. The concentration of 50 mgL−1 was within the ideal limit of three minutes recommended for surgical anesthesia induction and did not significantly increase glucose levels when compared to the control group (35.7±19.4 mg dL−1), besides not causing gill injuries. At this concentration the fish presented controlled blood glucose levels within the basal levels, besides not taking the risk to have later problems concernig mortality, because this concentration ensures the good health of the gills and good recovery of the animals.(AU)

O uso de anestésicos em pisciculturas é indispensável para reduzir o estresse durante o manejo. O presente trabalho propôs avaliar o efeito do eugenol como anestésico para manejo do curimatã (Prochilodus nigricans). Foram utilizados 50 espécimes (221,34±9,0 g; 25,8 ±1,1 cm), submetidos a cinco tratamentos com concentrações de 0, 25, 50, 100 e 200 mg L−1 de eugenol em exposição de 10 minutos. Foram registrados os tempos necessários para atingir cada estágio anestésico e a recuperação de cada peixe. Para verificação dos níveis de glicose sanguínea, foram realizadas coletas individuais de sangue dos peixes antes da imersão e após os 10 minutos de exposição ao anestésico. A avaliação do efeito do anestésico sobre as brânquias foi realizada por meio de análises histopatológicas. A concentração de 50 mg L−1 ficou dentro do limite ideal de três minutos preconizado para indução à anestesia cirúrgica e não elevou significativamente os níveis de glicose quando comparada ao grupo controle (35,7±19,4 mg dL−1), além de não provocar lesões branquiais. Nessa concentração, os peixes apresentaram níveis de glicose sanguínea controlada, dentro dos teores basais, além de não correrem o risco de apresentarem problemas posteriores em relação à mortalidade, pois essa concentração garante a boa saúde das brânquias e uma boa recuperação dos animais.(AU)

A National, Palliative Care Competency Framework for Undergraduate Medical Curricula.

As nearly all doctors deal with patients requiring palliative care, it is imperative that palliative care education starts early. This study aimed to validate a national, palliative care competency framework for undergraduate medical curricula. We conducted a Delphi study with five groups of stakeholders (palliative care experts, physicians, nurses, curriculum coordinators, and junior doctors), inviting them to rate a competency list. The list was organized around six key competencies. For each competency, participants indicated the level to which students should have mastered the skill at the end of undergraduate training. Stability was reached after two rating rounds (N = 82 round 1, N = 54 round 2). The results showed high levels of agreement within and between stakeholder groups. Participants agreed that theoretical knowledge is not enough: Students must practice palliative care competencies, albeit to varying degrees. Overall, communication and personal development and well-being scored the highest: Junior doctors should be able to perform these in the workplace under close supervision. Advance care planning scored the lowest, indicating performance in a simulated setting. A wide range of stakeholders validated a palliative care competency framework for undergraduate medical curricula. This framework can be used to guide teaching about palliative care.

Diferentes momentos de aplicação de gonadotrofina coriônica equina em protocolo de inseminação artificial em tempo fixo para vacas de leite / Different times of application of equine chorionic gonadotropin in fixed-time artificial insemination protocols for dairy cows

Avaliaram-se diferentes momentos de aplicação da gonadotrofina coriônica equina (eCG) em protocolos de inseminação artificial em tempo fixo (IATF) para vacas de leite. Foram utilizadas 76 fêmeas, as quais receberam, no dia zero (D0) do protocolo, dispositivos intravaginais de progesterona, sendo esses retirados no D9, e os animais foram, então, distribuídos aleatoriamente em três tratamentos: T1 - aplicação de eCG no momento da retirada dos dispositivos; T2 e T3 - aplicação de eCG 48h e 24h antes da retirada dos dispositivos, respectivamente. No D10 os animais receberam 1mg de GnRH, e a IATF foi realizada 52 horas após a retirada do implante. Não houve diferença (P>0,05) para intervalo entre a retirada do implante à ovulação (72,56±3,92h), o diâmetro do maior folículo no D9 (10,88±1,49mm), o diâmetro do folículo ovulatório (15,15±1,16mm) e do segundo maior folículo (7,49±0,52mm), a taxa de crescimento folicular (1,38±0,04mm/dia), a taxa de ovulação (96,67%), o intervalo entre diâmetro final e inicial do folículo dominante (73,49±3,84h), a área de corpo lúteo (2,27±0,43cm²), a porcentagem de CL no ovário direito (53,00%) e no esquerdo (26,33%) e a taxa de gestação (33,33%). O momento da aplicação da eCG não influenciou na eficiência do protocolo. Recomenda-se a utilização da eCG no momento da retirada do implante por otimização do manejo.(AU)

Different times of application of equine chorionic gonadotropin (eCG) in Fixed-Time Artificial Insemination (FTAI) protocols for dairy cows were evaluated. A total of 76 females were used, which received intravaginal progesterone devices on day zero (D0) of the protocol, which were withdrawn on D9, and the animals were then randomly distributed in three treatments: T1- application of eCG at the time of device withdrawal; T2 and T3 - application of eCG 48h and 24h before withdrawal of the devices, respectively. On D10 the animals received 1mg of GnRH and the FTAI was carried out 52 hours after the removal of the implant. There was no difference (P>0.05) for interval from implant removal to ovulation (72.56±3.92h), diameter of the largest follicle of D9 (10.88±1.49mm), diameters of ovulatory follicle (15.15±1.16mm) and of the second largest follicle (7.49±0.52mm), follicle growth rate (1.38±0.04mm/day), ovulation rate (96.67%), interval between final diameter and initial diameter of dominant follicle (73.49±3.84h), corpus luteum area (2.27±0.43cm²), percentage of CL in right ovary (53.00%) and in left ovary (26.33%) and pregnancy rate (33.33%). The time of the application of eCG did not influence the efficiency of the protocol. We recommend the use of eCG at the time of the removal of the implant for management optimization.(AU)

Palliative care education in the undergraduate medical curricula: students' views on the importance of, their confidence in, and knowledge of palliative care.

BACKGROUND: The need for palliative care is increasing. Since almost every junior doctor will come across palliative care patients, it is important to include palliative care in the undergraduate curriculum. The objective of this research is to gather undergraduate students' views on palliative care in terms of its importance, their confidence in and knowledge of the domain. METHODS: Final-year medical students at four Dutch medical faculties were surveyed. The questionnaire measured their views on the education they had received, their self-reported confidence in dealing with palliative care patients and their knowledge of palliative care. RESULTS: Two hundred twenty-two medical students participated in this study. Students considered palliative care education relevant, especially training in patient-oriented care and communication with the patient. Students felt that several topics were inadequately covered in the curriculum. Overall, the students did not feel confident in providing palliative care (59.6%), especially in dealing with the spiritual aspect of palliative care (77%). The knowledge test shows that only 48% of the students answered more than half of the questions correctly. CONCLUSION: The students in this study are nearly junior doctors who will soon have to care for palliative patients. Although they think that palliative care is important, in their opinion the curriculum did not cover many important aspects, a perception that is also in line with their lack of confidence and knowledge in this domain. Therefore, it is important to improve palliative care education in the medical curriculum.

Diagnostic accuracy of thromboelastometry and its correlation with the HPLC-MS/MS quantification test.

The aim of the study was to evaluate the diagnostic accuracy of thromboelastometry for assessing rivaroxaban concentrations. The accuracy of thromboelastometry was compared with the high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method, which is the gold standard for drug plasma monitoring (the reference standard). Forty-six clinically stable patients were treated with 10, 15, or 20 mg of rivaroxaban once daily (OD group) or 15 mg twice a day (BID group) (no particular indication for treatment). Patient samples were collected 2 h after the use of the medication (peak) and 2 h before the next dose (trough). The rivaroxaban plasma concentrations were determined via HPLC-MS/MS, and thromboelastometry was performed using a ROTEM® delta analyzer. There were significant prolongations in clotting time (CT) for the 10, 15, and 20 mg of rivaroxaban treatments in the OD groups. In the 15 mg BID group, the responses at the peak and trough times were similar. At the peak times, there was a positive correlation between the plasma concentration of rivaroxaban and CT (Spearman correlation rho=0.788, P<0.001) and clot formation time (rho=0.784, P<0.001), and a negative correlation for alpha angle (rho=-0.771, P<0.001), amplitude after 5 min (rho=-0.763, P<0.001), and amplitude after 10 min (rho=-0.680, P<0.001). The CT presented higher specificity and sensitivity using the cut-off determined by the receiver characteristics curve. ROTEM has potential as screening tool to measure possible bleeding risk associated with rivaroxaban plasma levels.

Diagnostic accuracy of thromboelastometry and its correlation with the HPLC-MS/MS quantification test

The aim of the study was to evaluate the diagnostic accuracy of thromboelastometry for assessing rivaroxaban concentrations. The accuracy of thromboelastometry was compared with the high-performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method, which is the gold standard for drug plasma monitoring (the reference standard). Forty-six clinically stable patients were treated with 10, 15, or 20 mg of rivaroxaban once daily (OD group) or 15 mg twice a day (BID group) (no particular indication for treatment). Patient samples were collected 2 h after the use of the medication (peak) and 2 h before the next dose (trough). The rivaroxaban plasma concentrations were determined via HPLC-MS/MS, and thromboelastometry was performed using a ROTEM® delta analyzer. There were significant prolongations in clotting time (CT) for the 10, 15, and 20 mg of rivaroxaban treatments in the OD groups. In the 15 mg BID group, the responses at the peak and trough times were similar. At the peak times, there was a positive correlation between the plasma concentration of rivaroxaban and CT (Spearman correlation rho=0.788, P<0.001) and clot formation time (rho=0.784, P<0.001), and a negative correlation for alpha angle (rho=−0.771, P<0.001), amplitude after 5 min (rho=−0.763, P<0.001), and amplitude after 10 min (rho=−0.680, P<0.001). The CT presented higher specificity and sensitivity using the cut-off determined by the receiver characteristics curve. ROTEM has potential as screening tool to measure possible bleeding risk associated with rivaroxaban plasma levels.

Time collection and storage conditions of lipid profile.

The stability of samples is crucial for getting reliable concentrations of many analytes, including lipid profile. Thus, the goal of this study was to analyze lipid profile under different storage and temperature conditions. This was a prospective study with 809 patients of both genders. Total cholesterol, triglycerides, high-density lipoprotein cholesterol, low density lipoprotein cholesterol and non-high-density lipoprotein were measured within 1 h from collection at room temperature, after 2-3 h of refrigeration (8°C) and after 4-5 h at room temperature. The processing time and storage conditions did not affect the analytes measured. These findings are important for multicenter studies, because of the difficulties related to centrifugation and freezing of samples immediately after collection.

Óleo de peixe associado ao ácido ascórbico no diluidor para criopreservação de sêmen caprino / Fish oil associated to ascorbic acid in diluter for cryopreservation goat semen

O presente estudo teve como objetivo avaliar o efeito da inclusão de óleo de peixe associado ao ácido ascórbico no diluidor para criopreservação de sêmen caprino. Dois machos da raça Boer foram submetidos à coleta de sêmen pelo método de vagina artificial, sendo os ejaculados avaliados quanto aos aspectos físicos e morfológicos. Após avaliação, formou-se um pool, seguido do fracionamento em cinco grupos: G1 - diluidor citrato-gema e G2, G3, G4 e G5 - diluidor citrato-gema acrescido de 1,0; 2,0; 3,0 e 4,0% de óleo de peixe e 0,05% de ácido ascórbico, respectivamente. Após descongelamento, foram realizadas avaliações físicas do sêmen e os testes complementares de termorresistência lento (TTR), hiposmótico (HO), integridade acrossomal e compactação da cromatina espermática. Houve comportamento linear crescente (P<0,05) para motilidade pós-descongelamento. Não houve diferença (P>0,05) para vigor pós-descongelamento (2,00±0,24). No TTR não houve diferença (P>0,05) para motilidade e vigor espermáticos entre os tempos cinco e 180min, com médias inicial e final de 62,17±12,13 e 14,29±10,55 para motilidade e de 2,00±0,52 e 0,49±0,44 para vigor. Não houve diferença (P>0,05) para o HO, com porcentagem média de espermatozoides reativos de 23,5±5,96%. Houve comportamento linear crescente para acrossoma íntegro e decrescente para acrossoma irregular (P<0,05). Não houve diferença (P>0,05) na compactação da cromatina, com 97,06±1,17% de cromatina íntegra. A inclusão até 4% de óleo de peixe acrescido de ácido ascórbico no diluidor melhorou motilidade e integridade de acrossoma após a criopreservação.(AU)

The study aimed to evaluate the effect of fish oil inclusion associated with ascorbic acid in the thinner for goat semen cryopreservation. Two male Boers underwent semen collection through the artificial vagina method, ejaculates being then assessed for physical and morphological aspects. After evaluation, a pool was formed, followed by the split into five groups: G1 - yolk-citrate extender and G2, G3, G4 and G5 - yolk-citrate extender plus 1.0; 2.0; 3.0 and 4.0% fish oil and 0.05% ascorbic acid, respectively. After thawing, physical evaluations of semen were assessed and additional testing slow heat resistance (TTR), hiposmotic (HO), acrosome integrity and compression of sperm chromatin. There was linear increase (P<0.05) post-thaw motility. No difference was obtained for post-thaw vigor and there was no influence of the association of fish oil and ascorbic acid in TTR. Plasma membrane integrity, by hyposmotic test (HO), presented a mean of reactive spermatozoa of 23.5±5.96% (P>0.05). There was linear increase for intact acrosome and decreasing acrosome irregular (P<0.05). In the analysis of the chromatin compaction, approximately 3% of damages (P>0.05) were observed. The inclusion of 4% fish oil plus ascorbic acid in diluter improved motility and acrosome integrity after cryopreservation.(AU)

Biomarcadores histológicos em brânquias de Sciades herzbergii (Siluriformes, Ariidae) capturados no Complexo Estuarino de São Marcos, Maranhão / Histological biomarkers in gills of Sciades herzbergii (Siluriformes, Ariidae) caught in the Estuarine Complex of São Marcos, Maranhão

Neste estudo, objetivou-se avaliar a qualidade ambiental de duas áreas do complexo estuarino de São Marcos, utilizando-se as alterações branquiais em Sciades herzbergii como biomarcadores de contaminação aquática. Foram realizadas coletas no período de estiagem (setembro/dezembro de 2015) e no período chuvoso (março/junho de 2016). Foram capturados 40 exemplares de S. herzbergii em dois locais distintos do complexo estuarino: A1) Porto do Itaqui Bacanga (área potencialmente impactada); A2) Igarapé do Puca, Alcântara (área controle). Foram registradas as variáveis abióticas: salinidade, temperatura, pH e oxigênio dissolvido. No laboratório, as brânquias de cada espécime foram fixadas em formol a 10% e mantidas em álcool a 70% até a execução da técnica histológica usual. As alterações branquiais identificadas nos peixes da área potencialmente contaminada foram: deslocamento do epitélio (DE), congestão (CO), aneurisma (AN), fusão lamelar (FL), hiperplasia (HI), dilatação capilar (DC), necrose (NE) e proliferação de células epiteliais (PCE). As alterações na região controle foram: deslocamento do epitélio (DE), fusão lamelar (FL), necrose (NE) e proliferação de células epiteliais (PCE). As alterações branquiais foram mais frequentes na região portuária (84%) do que na região controle (16%). Esses resultados indicam que os peixes da área potencialmente contaminada estão apresentando respostas biológicas ao estresse local.(AU)

This study aimed to compare an environmental quality of two areas of the estuarine complex of São Marcos using gills of changes in Sciades herzbergii as biomarkers of aquatic contamination. Samples were made during the dry season (September/ December 2015) and rainy season (March/ June 2016). They were captured 40 specimens of S. herzbergii at two different points of the estuarine complex: A1) Itaqui port (potentially contaminated area); A2) Igarapé do Puca, Alcântara (control area). Abiotic variables were recorded: salinity, temperature, pH and dissolved oxygen. In the laboratory, the gills of each species were fixed in 10% formaldehyde and kept in 70% alcohol until the usual histological technique was performed. The gill alterations identified in the fish of the potentially contaminated area were: epithelial displacement (DE), congestion (CO), aneurysm (AN), lamellar fusion (FL), hyperplasia (HI), capillary dilation (DC), necrosis and epithelial cell proliferation (PCE). The changes in the control region were: epithelial displacement (DE), lamellar fusion (FL), necrosis (NE) and epithelial cell proliferation (PCE). Gill alterations were more frequent in the port region (84%) than in the control region (16%). These results indicate that fish from the potentially contaminated area are presenting biological responses to local stress.(AU)

Factors associated with dental anxiety in Brazilian children during the first transitional period of the mixed dentition.

AIMS: To determine the prevalence of dental anxiety in children during the first transitional period of the mixed dentition and associated factors. METHODS: A Cross-sectional study was performed with 1367 children of both genders aged 6-7 years old conducted in schools in Recife, Brazil in 2013. The data were collected through interviews and intra-oral examinations. Dental anxiety data were obtained using the dental anxiety questionnaire (DAQ). The associated factors considered were: age, gender, social group, child's experience with the dentist, history of dental pain, experience of caries and phase of exfoliation. RESULTS: The prevalence of children with some level of dental anxiety was 54.4%. Visit to the dentist and social group were associated with dental anxiety (p < 0.001). CONCLUSIONS: The prevalence of dental anxiety was high, although children attending private schools and those who had visited the dentist before had a lower prevalence of dental anxiety.

The opinion of children and their parents about four different types of dental restorations in a public health service in Brazil.

AIM: To investigate the opinion of children and their parents of four different types of restoration placed in primary molars. METHODS: A mixed method study in which both children and their parents were involved. In the quantitative study, children and parents gave their opinion using a face scale about four different types of restoration immediately after placement, evaluating how satisfied they were. In the qualitative part, children and their parents were interviewed to report their preference among the four types of restoration using dental models and photos. RESULTS: In the quantitative study, 1045 restorations were placed, being conventional restorations (198 with amalgam and 205 with composite resin) and atraumatic interventions [408 with glass ionomer: ART, atraumatic restorative treatment, and 234 with preformed metal crowns (PMCs): Hall technique]. Almost all participants (children and parents) gave a positive opinion (from 94.9 to 100%) on the four types of restoration placed in the children's teeth. There was no statistical significant difference in opinion in terms of acceptance of the four types of restoration placed (Chi square test, p value > 0.05). In the qualitative approach, 18 children and 11 parents were interviewed. If they could choose, children (16/18) preferred the PMCs, while parents (10/11) preferred aesthetic materials such as composite resin and glass ionomer cement. CONCLUSIONS: A high degree of satisfaction was observed with children and their parents in the four types of restoration after placement. However, if it could be chosen in advance, children prefer the PMCs and parents a tooth-coloured material.

Antibacterial and non-cytotoxic ultra-thin polyethylenimine film.

In recent years, a common strategy, to obtain more uniform and controlled synthesis of polyelectrolytes multilayers (PEMs), relies on a previous polyethylenimine (PEI) coating of the substrate surface. PEI is a synthetic cationic polymer which provides a positive charge distribution on the materials to be covered with PEMs. Despite being an important step, this pre-layer deposition is frequently overlooked and no comprehensive characterizations or deep discussions are reported in literature. In that sense, this work reports on the synthesis of a typical PEI film that works as a precursor for PEMs, and its detailed physicochemical characterization. As many PEMs are produced for antibacterial and biomedical applications, the cytotoxicity of the film was also tested using fibroblasts, and its antibacterial activity was studied using Staphylococcus aureus and Pseudomonas aeruginosa. Our results present the formation of an ultra-thin film of PEI with a thickness around 3.5nm, and with a significant percent of NH3+ (35% of the total amount of N) in its chemical structure; NH3+ is a key chemical group because it is considered an important bacterial killer agent. The film was stable and did not present important cytotoxic effect for fibroblasts up to 7days, contrary to other reports. Finally, the PEI film showed high antibacterial activity against the S. aureus strain: reductions in cell density were higher than 95% up to 24h.

Saccharomyces cerevisiae UFMG A-905 treatment reduces intestinal damage in a murine model of irinotecan-induced mucositis.

Indigenous microbiota plays a crucial role in the development of several intestinal diseases, including mucositis. Gastrointestinal mucositis is a major and serious side effect of cancer therapy, and there is no effective therapy for this clinical condition. However, some probiotics have been shown to attenuate such conditions. To evaluate the effects of Saccharomyces cerevisiae UFMG A-905 (Sc-905), a potential probiotic yeast, we investigated whether pre- or post-treatment with viable or inactivated Sc-905 could prevent weight loss and intestinal lesions, and maintain integrity of the mucosal barrier in a mucositis model induced by irinotecan in mice. Only post-treatment with viable Sc-905 was able to protect mice against the damage caused by chemotherapy, reducing the weight loss, increase of intestinal permeability and jejunal lesions (villous shortening). Besides, this treatment reduced oxidative stress, prevented the decrease of goblet cells and stimulated the replication of cells in the intestinal crypts of mice with experimental mucositis. In conclusion, Sc-905 protects animals against irinotecan-induced mucositis when administered as a post-treatment with viable cells, and this effect seems to be related with the reduction of oxidative stress and preservation of intestinal mucosa.