Nanosilica and copper ecotoxicity in Gambusia holbrooki fish.

When silica nanoparticles (SiNP) reach the water bodies interact with the already existing pollutants in the environments. This study aimed to evaluate the ecotoxicity of SiNP under the presence/absence of Cu in mosquitofish (Gambusia holbrooki). Fish were exposed to 0, 10 and 100 mg SiNP L-1, alone or mixed with Cu (0.25 mg L-1). After 96 h, the amount of colony forming units (CFU) of bacteria living on the skin mucus was analysed, and oxidative stress, tissue damage enzymes, and neurotoxicity were evaluated. We observed a reduction in CFU when Cu was present in the media. The liver was the target organ, evidencing a decrease in tissue damage enzymatic activities, activation of the antioxidant system in all treatments, and lipid oxidative damage when the SiNP and Cu were mixed. Overall, SiNP ecotoxicity was proved, which could also be enhanced by the presence of ubiquitous elements such as metals.

Detection of Streptococcus mutans and Streptococcus sobrinus and Their Association with Oral Microbiome Stressors in 6-18-month-old Infants.

Aim: To determine the presence of Streptococcus mutans (S. mutans) and Streptococcus sobrinus (S. sobrinus) and their association with extrinsic and intrinsic variables in 6-18-month-old infants. Methods: This was an analytical, cross-sectional study of 65 6-18-month-old infants who visited the Centers for Early Childhood in Buenos Aires City. Three groups were established according to the presence of teeth-group I (GI)-edentulous infants, group II (GII)-infants with 1-8 teeth, and group III (GIII)-infants with 9-16 teeth. Data on the variables, diet, use of artificial teats, and oral hygiene were gathered using a self-administered questionnaire. An oral examination was performed according to the International Caries Detection and Assessment System (ICDAS II) criterion. A saliva sample was taken by aspiration with a sterile plastic syringe. Cariogenic Streptococci (CS) were counted using the adherence test in modified gold broth (AT-MGB). Molecular detection and quantification were performed by quantitative polymerase chain reaction (qPCR) (gtfB, gtfT, and tuf). Results: A total of 12% of infants received oral hygiene, 38% used bottles, 30% used pacifiers, and 55% had sugar intake. S. sobrinus and S. mutans were detected in 57.1 and 28.6% of the children with caries, respectively. Groups I, II, and III had CS counts of log 2, 3.4, and 3.7, respectively. S. sobrinus was detected in 26.7% of GI, 52.9% of GII, and 85.7% of GIII, while S. mutans was detected in 13.3%, 35.3%, and 57.7%, respectively. Conclusion: The prevalence of S. sobrinus was higher than S. mutans in all groups. The presence of CS was significantly associated with sugar intake. No association was found between S. mutans and S. sobrinus and the presence of caries, hygiene habits, or use of artificial teats. Clinical Significance: This study supports the role of diet in developing a cariogenic biofilm in children under 2 years of age. How to cite this article: Cornejo CF, Soken LJ, Salgado PA, et al. Detection of Streptococcus mutans and Streptococcus sobrinus and Their Association with Oral Microbiome Stressors in 6-18-month-old Infants. Int J Clin Pediatr Dent 2023;16(1):68-73.

Effect of staining on the mechanical, surface and biological properties of lithium disilicate.

PURPOSE: To simulate biodegradation and wear of stained and glazed CAD lithium disilicate ceramic, and evaluate their effects on the microbial adherence and mechanical and surface properties of lithium disilicate ceramic. MATERIALS AND METHODS: 160 lithium disilicate ceramic discs were fabricated and divided in eight groups according to manual stain and glaze application with a fine paint brush (without stain and glaze; with stain and glaze) and aging procedures (no aging; wear at 30 N load, 1.7 Hz, 3 × 105 cycles; biodegradation by exposure to microcosm biofilm; biodegradation + wear; biodegradation + wear). Profilometry was performed to determine the surface roughness and the wear consequences. Biaxial flexural strength test was performed, and a Streptococcus mutans adherence test was conducted to evaluate the number of colony forming units. RESULTS: Unaged samples with and without stain and glaze presented the lowest values of surface roughness (p < 0.001), but after aging (wear, biodegradation, or both), the samples in the stain and glaze groups were rougher than those in the no stain and glaze groups (p < 0.001). The stain and glaze groups showed the highest volume of wear after aging (p = 0.04), and had the lowest flexural strength values (p < 0.01), irrespective of the aging method. The aging method did not affect the flexural strength (p = 0.06). The number of colonies forming units was higher for biodegradation + no stain and glaze, biodegradation + wear + no stain and glaze, no aging + stain and glaze, biodegradation + stain and glaze, and biodegradation + wear + stain and glaze. The lowest values were observed for no aging + no stain and glaze. CONCLUSION: The staining and glazing of lithium disilicate increased the surface wear and bacterial adherence, and decreased biaxial flexural strength of the material. When exposed to S. mutans, surface roughness increased, and biodegradation favored bacterial adherence.

Colony-forming units optimization and human papillomavirus detection in umbilical cord blood.

INTRODUCTION: Analysis of several parameters is required for adequate quality control in umbilical cord blood units (UCBU) when used for therapeutic purposes. OBJECTIVE: To optimize colony-forming units (CFU) from clonogenic cultures and to detect the human papillomavirus (HPV) genome in UCBU. METHODS: One hundred and forty-one umbilical cord blood (UCB), segment or CFU samples from UCBU clonogenic cultures were included. DNA extraction, quantification and endogenous GAPDH gene PCR amplification were carried out. Subsequently, HPV L1 gene was detected using the MY09/MY11 and GP5/GP6+ oligonucleotides. PCR products were analyzed with electrophoresis in agarose gel. CFU-extracted purified DNA was analyzed by electrophoresis in agarose gel, as well as some DNAs, using the sequence-specific priming technique. RESULTS: CFU-extracted DNA concentration was higher in comparison with that of UCB (p = 0.0041) and that of the segment (p < 0.0001), as well as that of UCB in comparison with that of the segment (p < 0.0001). All samples were positive for GAPDH amplification and negative for MY09/MY/11 and GP5/GP6+. CONCLUSIONS: Cryopreserved UCBUs were HPV-negative. Obtaining CFU DNA from clonogenic cultures with high concentrations and purity is feasible.

INTRODUCCIÓN: Se requiere analizar diversos parámetros para el control de calidad adecuado de las unidades de sangre de cordón umbilical (USCU) cuando se utilizan con fines terapéuticos. OBJETIVO: Optimizar las unidades formadoras de colonias (UFC) de cultivos clonogénicos y detectar el genoma del virus del papiloma humano (VPH) en USCU. MÉTODOS: Se incluyeron 141 muestras de sangre de cordón umbilical (SCU), de segmento y de UFC de cultivos clonogénicos de USCU. Se realizó extracción de ADN, cuantificación y amplificación por PCR del gen endógeno GAPDH. Se detectó el gen L1 del VPH con los oligonucleótidos MY09/MY11 y GP5/GP6+; los productos de PCR se migraron en electroforesis de agarosa. El ADN purificado de las UFC se analizó mediante electroforesis de agarosa y algunos ADN, con la técnica sequence specific priming. RESULTADOS: La concentración de ADN extraído de UFC fue superior comparada con la de SCU (p = 0.0041) y la de segmento (p < 0.0001); así como la de SCU comparada con la de segmento (p < 0.0001). Todas las muestras fueron positivas para la amplificación de GAPDH y negativas para MY09/MY11 y GP5/GP6+. CONCLUSIONES: Las USCU criopreservadas fueron VPH netativas; además, es factible obtener ADN en altas concentraciones y con alta pureza a partir de UFC de los cultivos clonogénicos.

16α-Bromoepiandrosterone as a new candidate for experimental diabetes-tuberculosis co-morbidity treatment.

Tuberculosis (TB) is the leading cause of death from a single bacterial infectious agent and is one of the most relevant issues of public health. Another pandemic disease is type II diabetes mellitus (T2D) that is estimated to affect half a billion people in the world. T2D is directly associated with obesity and a sedentary lifestyle and is frequently associated with immunosuppression. Immune dysfunction induced by hyperglycemia increases infection frequency and severity. Thus, in developing countries the T2D/TB co-morbidity is frequent and represents one of the most significant challenges for the health-care systems. Several immunoendocrine abnormalities are occurring during the chronic phase of both diseases, such as high extra-adrenal production of active glucocorticoids (GCs) by the activity of 11-ß-hydroxysteroid dehydrogenase type 1 (11-ßHSD1). 11-ßHSD1 catalyzes the conversion of inactive cortisone to active cortisol or corticosterone in lungs and liver, while 11-ß-hydroxysteroid dehydrogenase type 2 (11-ßHSD2) has the opposite effect. Active GCs have been related to insulin resistance and suppression of Th1 responses, which are deleterious factors in both T2D and TB. The anabolic adrenal hormone dehydroepiandrosterone (DHEA) exerts antagonistic effects on GC signaling in immune cells and metabolic tissues; however, its anabolic effects prohibit its use to treat immunoendocrine diseases. 16α-bromoepiandrosterone (BEA) is a water miscible synthetic sterol related to DHEA that lacks an anabolic effect while amplifying the immune and metabolic properties with important potential therapeutic uses. In this work, we compared the expression of 11-ßHSD1 and the therapeutic efficacy of BEA in diabetic mice infected with tuberculosis (TB) (T2D/TB) with respect to non-diabetic TB-infected mice (TB). T2D was induced by feeding mice with a high-fat diet and administering a single low-dose of streptozotocin. After 4 weeks of T2D establishment, mice were infected intratracheally with a high-dose of Mycobacterium tuberculosis strain H37Rv. Then, mice were treated with BEA three times a week by subcutaneous and intratracheal routes. Infection with TB increased the expression of 11-ßHSD1 and corticosterone in the lungs and liver of both T2D/TB and TB mice; however, T2D/TB mice developed a more severe lung disease than TB mice. In comparison with untreated animals, BEA decreased GC and 11-ßHSD1 expression while increasing 11-ßHSD2 expression. These molecular effects of BEA were associated with a reduction in hyperglycemia and liver steatosis, lower lung bacillary loads and pneumonia. These results uphold BEA as a promising effective therapy for the T2D/TB co-morbidity.

Biocompatibility with the Ocular Surface and Antimicrobial Activity of a New Multi-Purpose Contact Lens Solution / Biocompatibilidad con la superficie ocular y actividad antimicrobiana de una nueva solución multipropósito para lentes de contacto / Biocompatibilidade com a superfície ocular e atividade antimicrobiana de uma nova solução de lentes de contato multipropósito

Abstract Introduction: Multipurpose solutions (MPS) for soft contact lenses (SCL) play an essential role in inhibiting potentially pathogenic agents. Their antimicrobial effectiveness is assessed in vitro and their safety in vivo, with clinical trials that include a combination of different solutions and lens materials. The objective is to assess the biocompatibility of a new SCL MPS produced in Colombia that contains polyhexamethylene biguanide (PHMB) and to determine its antimicrobial activity. Materials and Methods: This was a crossover study with 25 subjects who did not wear lens and who were fitted with different combinations of five SCL materials with either MPS or control physiological saline solution (CS). Corneal thickness, conjunctival hyperemia, corneal staining, and comfort were assessed after two hours of wearing SCL. Antimicrobial effectiveness was measured using ISO 14729 standard assays. Results: When considering SCL material, there was a statistically significant difference between the new MPS and the CS for Comfilcon A (p < 0.05). There was no statistical or clinically significant difference for corneal thickness or corneal staining between the combination of lens material and new MPS with the CS (p > 0.05). After two hours of lens insertion, comfort scores were higher than 7.8. The MPS reduced bacteria colony forming units (CFU) in over 3 log, and fungal CFU in over 1.0 log. Conclusions: The new MPS met the antimicrobial standards of ISO 14729, is considered safe and biocompatible with the ocular surface and retains high comfort levels.

Resumen Introducción: las soluciones multipropósito (SMP) para lentes de contacto blandos (LCB) desempeñan un papel esencial en la inhibición de agentes potencialmente patógenos. Su efectividad antimicrobiana se evalúa in vitro, y su seguridad, in vivo, con ensayos clínicos que incluyen una combinación de diferentes soluciones y materiales para lentes. El objetivo es evaluar la biocompatibilidad de una nueva SMP producida en Colombia que contiene polihexametileno biguanida (PHMB) y determinar su actividad antimicrobiana. Materiales y métodos: estudio cruzado con 25 sujetos no usuarios de lentes, que fueron adaptados con cinco combinaciones diferentes de materiales de LCB con una nueva SMP o solución salina fisiológica de control (CS). El grosor corneal, la hiperemia conjuntival, la tinción corneal y la comodidad se evaluaron después de dos horas de uso del LC. La efectividad antimicrobiana se midió utilizando ensayos estándar ISO 14729. Resultados: considerando el material del LCB, solo hubo una diferencia estadísticamente significativa entre la nueva SMP y el CS para el Comfilcon A (p < 0.05). Tampoco hubo diferencias estadísticamente o clínicamente significativas para el grosor corneal o la tinción corneal, entre la combinación del material del lente y la nueva SMP con el CS (p > 0.05). Después de dos horas de uso del lente, las puntuaciones de confort fueron superiores a 7.8. La SMP redujo las unidades formadoras de colonias (UFC) de bacterias en más de 3 log, y las UFC fúngicas en más de 1.0 log. Conclusiones: la nueva SMP cumplió con los estándares antimicrobianos de ISO 14729, y se considera segura y biocompatible con la superficie ocular, con altos niveles de confort.

Resumo Introdução: as soluções multipropósito (SMP) para lentes de contato macias (LCM) apresentam um papel essencial na inibição de agentes potencialmente patógenos. Sua eficácia como agente antimicrobiano se valia in vitro, e sua segurança, in vivo, como ensaios clínicos que incluem uma combinação de diferentes soluções e materiais para lentes. O objetivo é avaliar a biocompatibilidade de uma nova SMP produzida na Colômbia a base de polihexametileno biguanida (PHMB) e determinar seu potencial antimicrobiano. Materiais e métodos: estudo cruzado com 25 indivíduos não usuários de lentes, que foram adaptados com cinco combinações diferentes de LCM como uma nova SMP ou solução salina fisiológica como controle (CS). A espessura da córnea, a hiperemia conjuntival, a coloração da córnea e a comodidade, foram avaliadas após duas horas de uso da LCB. A eficácia antimicrobiana foi medida com ensaios padrão ISO 14729. Resultados: considerando o material da LCB, houve apenas uma diferença estatisticamente significativa entre a nova SMP e o CS, paro o Comfilcon A (p <0.05). Não houve diferença estatisticamente ou clinicamente significativa para a espessura da córnea ou a coloração da córnea, entre a combinação do material da lente e a nova SMP com o controle CS (p > 0.05). Após duas horas de uso, as pontuações de conforto foram superiores a 7,8. A SMP reduziu as unidades formadoras de colônias (UFC) de bactérias em mais de 3 log, e as UFC fúngicas em mais de 1.0 log. Conclusões: a nova SMP cumpriu com os padrões antimicrobianos ISO 14729, é considerada segura e biocompatível com a superfície ocular, com altos níveis de conforto.

Equivolumetric Protocol Generates Library Sizes Proportional to Total Microbial Load in 16S Amplicon Sequencing.

High-throughput sequencing of 16S rRNA amplicon has been extensively employed to perform microbiome characterization worldwide. As a culture-independent methodology, it has allowed high-level profiling of sample bacterial composition directly from samples. However, most studies are limited to information regarding relative bacterial abundances (sample proportions), ignoring scenarios in which sample microbe biomass can vary widely. Here, we use an equivolumetric protocol for 16S rRNA amplicon library preparation capable of generating Illumina sequencing data responsive to input DNA, recovering proportionality between observed read counts and absolute bacterial abundances within each sample. Under specified conditions, we show that the estimation of colony-forming units (CFU), the most common unit of bacterial abundance in classical microbiology, is challenged mostly by resolution and taxon-to-taxon variation. We propose Bayesian cumulative probability models to address such issues. Our results indicate that predictive errors vary consistently below one order of magnitude for total microbial load and abundance of observed bacteria. We also demonstrate our approach has the potential to generalize to previously unseen bacteria, but predictive performance is hampered by specific taxa of uncommon profile. Finally, it remains clear that high-throughput sequencing data are not inherently restricted to sample proportions only, and such technologies bear the potential to meet the working scales of traditional microbiology.

Optimización de unidades formadoras de colonias y detección del virus de papiloma humano en sangre de cordón umbilical / Colony-forming units optimization and human papillomavirus detection in umbilical cord blood

Resumen Introducción: Se requiere analizar diversos parámetros para el control de calidad adecuado de las unidades de sangre de cordón umbilical (USCU) cuando se utilizan con fines terapéuticos. Objetivo: Optimizar las unidades formadoras de colonias (UFC) de cultivos clonogénicos y detectar el genoma del virus del papiloma humano (VPH) en USCU. Métodos: Se incluyeron 141 muestras de sangre de cordón umbilical (SCU), de segmento y de UFC de cultivos clonogénicos de USCU. Se realizó extracción de ADN, cuantificación y amplificación por PCR del gen endógeno GAPDH. Se detectó el gen L1 del VPH con los oligonucleótidos MY09/MY11 y GP5/GP6+; los productos de PCR se migraron en electroforesis de agarosa. El ADN purificado de las UFC se analizó mediante electroforesis de agarosa y algunos ADN, con la técnica sequence specific priming. Resultados: La concentración de ADN extraído de UFC fue superior comparada con la de SCU (p = 0.0041) y la de segmento (p < 0.0001); así como la de SCU comparada con la de segmento (p < 0.0001). Todas las muestras fueron positivas para la amplificación de GAPDH y negativas para MY09/MY11 y GP5/GP6+. Conclusiones: Las USCU criopreservadas fueron VPH netativas; además, es factible obtener ADN en altas concentraciones y con alta pureza a partir de UFC de los cultivos clonogénicos.

Abstract Introduction: Analysis of several markers is required for adequate quality control in umbilical cord blood units (UCBU) when are used for therapeutic purposes. Objective: To optimize colony-forming units (CFU) from clonogenic cultures and to detect the human papillomavirus (HPV) genome in UCBU. Methods: One hundred and forty-one umbilical cord blood (UCB), segment or CFU samples from UCBU clonogenic cultures were included. DNA extraction, quantification and endogenous GAPDH gene PCR amplification were carried out. Subsequently, HPV L1 gene was detected using the MY09/MY11 and GP5/GP6+ oligonucleotides. PCR products were analyzed with electrophoresis in agarose gel. CFU-extracted purified DNA was analyzed by electrophoresis in agarose gel, as well as some DNAs, using the SSP technique. Results: CFU-extracted DNA concentration was higher in comparison with that of UCB (p = 0.0041) and that of the segment (p < 0.0001), as well as that of UCB in comparison with that of the segment (p < 0.0001). All samples were positive for GAPDH amplification and negative for MY09/MY11 and GP5/GP6+. Conclusions: Cryopreserved UCBUs were HPV-negative. Obtaining CFU DNA from clonogenic cultures with high concentrations and purity is feasible.

Imaging and immunometabolic phenotyping uncover changes in the hepatic immune response in the early phases of NAFLD.

BACKGROUND & AIMS: The precise determination of non-alcoholic fatty liver disease (NAFLD) onset is challenging. Thus, the initial hepatic responses to fat accumulation, which may be fundamental to our understanding of NAFLD evolution and clinical outcomes, are largely unknown. Herein, we chronologically mapped the immunologic and metabolic changes in the liver during the early stages of fatty liver disease in mice and compared this with human NAFLD samples. METHODS: Liver biopsies from patients with NAFLD (NAFLD activity score [NAS] 2-3) were collected for gene expression profiling. Mice received a high-fat diet for short periods to mimic initial steatosis and the hepatic immune response was investigated using a combination of confocal intravital imaging, gene expression, cell isolation, flow cytometry and bone marrow transplantation assays. RESULTS: We observed major immunologic changes in patients with NAS 2-3 and in mice in the initial stages of NAFLD. In mice, these changes significantly increased mortality rates upon drug-induced liver injury, as well as predisposing mice to bacterial infections. Moreover, deletion of Toll-like receptor 4 in liver cells dampened tolerogenesis, particularly in Kupffer cells, in the initial stages of dietary insult. CONCLUSION: The hepatic immune system acts as a sentinel for early and minor changes in hepatic lipid content, mounting a biphasic response upon dietary insult. Priming of liver immune cells by gut-derived Toll-like receptor 4 ligands plays an important role in liver tolerance in initial phases, but continuous exposure to insults may lead to damage and reduced ability to control infections. LAY SUMMARY: Fatty liver is a very common form of hepatic disease, leading to millions of cases of cirrhosis every year. Patients are often asymptomatic until becoming very sick. Therefore, it is important that we expand our knowledge of the early stages of disease pathogenesis, to enable early diagnosis. Herein, we show that even in the early stages of fatty liver disease, there are significant alterations in genes involved in the inflammatory response, suggesting that the hepatic immune system is disturbed even following minor and undetectable changes in liver fat content. This could have implications for the diagnosis and clinical management of fatty liver disease.

Coinoculation of soybean plants with Bradyrhizobium japonicum and Trichoderma harzianum: Coexistence of both microbes and relief of nitrate inhibition of nodulation.

Coinoculation of plants with mixtures of beneficial microbes sometimes produces synergistic effects. In this study, the effect of soybean coinoculation with the N2-fixing Bradyrhizobium japonicum E109 and the biocontrol fungus Trichoderma harzianum Th5cc was analyzed. Nodulation by E109 was not hampered by Th5cc, which antagonized five out of seven soybean pathogens tested. Furthermore, Th5cc relieved nitrate-inhibition of nodulation, enabling the formation of nodules containing infected cells with bacteroids in the presence of the otherwise inhibitory 10 mM KNO3. Th5cc released micromolar amounts of auxin, and addition of 11 µM indoleacetic acid to soybean plants inoculated with E109 in the absence of Th5cc also induced nodulation in the presence of 10 mM KNO3. Thus, Th5cc may release auxins into the soybean rhizosphere, which hormones might participate in overcoming the nitrate-inhibition of nodulation. Our results suggest that soybean plants coinoculated with these microorganisms might benefit from biocontrol while contributing to soil-nitrogen preservation.

Quantification of Bacteria Residing in Caenorhabditis elegans Intestine.

Quantification of intestinal colonization by pathogenic or commensal bacteria constitute a critical part of the analysis to understand host-microbe interactions during different time points of their interplay. Here we detail a method to isolate non-pathogenic and pathogenic bacteria from C. elegans intestines, and classify gut phenotypes induced by bacterial pathogens using fluorescently-tagged bacteria. Furthermore, these methods can be used to isolate and identify new culturable bacterial species from natural microbiomes of wild nematodes.

Bacterial viability after antimicrobial photodynamic therapy with curcumin on multiresistant Staphylococcus aureus.

Staphylococcus aureus are multiresistant pathogens that causes superficial and systemic infections. Antimicrobial photodynamic therapy (APDT) is an alternative in the treatment of diseases caused by these bacteria. Aim: In this study the APDT response on growth, viability, formation of reactive oxygen species and adhesion of methicillin-sensitive strains of Staphylococcus aureus, strains of methicillin-resistant S. aureus and American-type culture collection (ATCC) of S. aureus were evaluated in vitro, after incubation with curcumin for 20 min, and irradiated with LED. Materials & methods: Bacterial growth was assessed by the number of colony-forming units, viability and adhesion were evaluated by confocal microscopy and ROS quantification was performed by fluorimetry. Results: Was observed increase in the production of ROS in APDT groups, besides a decrease in the 4 log growth and loss of the bacterial adhesion. Conclusion: APDT with Curcumin may be an interesting therapeutic alternative, due to its in vitro response, in the control multiresistant clinical S. aureus strains.

A review of select minerals influencing the haematopoietic process.

Micronutrients are indispensable for adequate metabolism, such as biochemical function and cell production. The production of blood cells is named haematopoiesis and this process is highly consuming due to the rapid turnover of the haematopoietic system and consequent demand for nutrients. It is well established that micronutrients are relevant to blood cell production, although some of the mechanisms of how micronutrients modulate haematopoiesis remain unknown. The aim of the present review is to summarise the effect of Fe, Mn, Ca, Mg, Na, K, Co, iodine, P, Se, Cu, Li and Zn on haematopoiesis. This review deals specifically with the physiological requirements of selected micronutrients to haematopoiesis, showing various studies related to the physiological requirements, deficiency or excess of these minerals on haematopoiesis. The literature selected includes studies in animal models and human subjects. In circumstances where these minerals have not been studied for a given condition, no information was used. All the selected minerals have an important role in haematopoiesis by influencing the quality and quantity of blood cell production. In addition, it is highly recommended that the established nutrition recommendations for these minerals be followed, because cases of excess or deficient mineral intake can affect the haematopoiesis process.

Assessment of Candida SPP. proliferation in occlusal and palatal splints / Avaliação da proliferação Candida SPP. em placas oclusais e palatais

Candida species inhabit the oral cavity of all individuals who wear complete denture and whose material is the same as that used in splints. Assess the growth of C. albicans in occlusal and palatal splints used for treatment of TMD so that the potential risks of oral microbiota can be assessed. The growth of Candida spp. was assessed in the saliva of 27 individuals wearing splints for treatment of TMD. They were divided into two groups: G1 (n = 14), individuals wearing occlusal splint; and G2 (n = 13), individuals wearing palatal splint. Saliva samples were collected during placement of the splints (T1) and after 4 months (T2), being stored in PBS (10 mL) after 60-second rinses. It was observed that patients wearing occlusal splints (G1) had an increase of 0.648 CFU/mL (Log 10), with statistically significant differences (P = 0.043) for C. albicans (42.33%), C. glabrata (5.52%), C. krusei (41.72%) and C. tropicalis (10.43%). In the group of patients wearing palatal splints (G2), there was a decrease of 0.101 CFU/mL (Log 10), was observed with (P = 0.964) only the presence of C. albicans. The results suggest that growth of Candida species was greater in patients wearing occlusal splints compared to those wearing palatal ones as the presence of different yeast species was found in the former.

Espécies de Candida habitam a cavidade oral de 60-100% de indivíduos usuários de prótese total, cujo material é o mesmo utilizado em placas miorrelaxante. Avaliar o crescimento de C. albicans. em placas relaxantes musculares oclusais e palatais, usadas para o tratamento de DTM, na intenção de verificar riscos em potencial à microbiota bucal. Avaliou-se o crescimento de Candida spp. na saliva de 27 indivíduos, usuários de placa miorrelaxante, em tratamento para DTM no ICT-UNESP. Os indivíduos foram divididos em dois grupos: G1(n=14) ­ placa com recobrimento oclusal; e G2 (n=13) ­ sem recobrimento. As coletas foram com PBS (10mL), em bochechos por 60seg, na instalação das placas (T1) e após 4 meses (T2). Observou-se que pacientes usuários da placa miorrelaxante com recobrimento oclusal (grupo G1) apresentaram aumento de 0,648 UFC/mL (Log10) com diferença estatisticamente significante (p=0,043) analisando-se 42,33% C. albicans, 5,52% C. glabrata, 41,72% C. krusei e 10,43% C. tropicalis. No grupo de pacientes que utilizaram a placa sem recobrimento (grupo G2), observou-se diminuição de 0,101 UFC/mL (Log10) com (p=0,954) apresentando apenas C. albicans. Os resultados sugerem que os pacientes que fizeram uso de placa miorrelaxante com recobrimento oclusal apresentaram maior crescimento de Candida spp. em relação aos usuários de placa sem recobrimento, verificando-se a presença de diferentes espécies da levedura.

Equisetum giganteum influences the ability of Candida albicans in forming biofilms over the denture acrylic resin surface.

CONTEXT: Equisetum giganteum L. (Equisetaceae) is an endemic plant of Central and South America used in traditional medicine. Natural drugs have been frequently used in the treatment of a myriad of diseases, proving to be an alternative to synthetic chemicals, and have been intensively studied in the prevention of sicknesses, including oral diseases. OBJECTIVE: This study evaluated the in vitro antiadherent activity of E. giganteum extract against Candida albicans biofilms. MATERIALS AND METHODS: Crystal violet and colony-forming units assays were used to quantify the total biofilm biomass and biofilm living cells on a denture base acrylic resin pretreated with hydroethanolic extract of E. giganteum in different concentrations (50, 25, 16, 8, and 4 mg/mL), after 24 h of biofilm development. RESULTS: Equisetum giganteum affected biofilms by reduction of biomass and living cells per area of acrylic specimens. The results revealed reduction of 15-44% of the biofilm mass and reduction of numbers of colony-forming units (CFUs) present in biofilms (79%) compared to the untreated control (CTRL/PBS). At all concentrations, it demonstrated important antiadherent activity on Candida albicans biofilms, the main microbe in denture stomatitis. DISCUSSION AND CONCLUSION: The present findings show that E. giganteum antimicrobial effects may qualify the extract as a promising natural alternative for topical treatment or prevention of denture stomatitis. The usage of drugs made of natural products shows advantages in relation to synthetic drugs on the market, such as lower cost, lower toxicity, and in relation to the occurrence of microbial resistance.

Milk kefir: nutritional, microbiological and health benefits.

Kefir is fermented milk produced from grains that comprise a specific and complex mixture of bacteria and yeasts that live in a symbiotic association. The nutritional composition of kefir varies according to the milk composition, the microbiological composition of the grains used, the time/temperature of fermentation and storage conditions. Kefir originates from the Caucasus and Tibet. Recently, kefir has raised interest in the scientific community due to its numerous beneficial effects on health. Currently, several scientific studies have supported the health benefits of kefir, as reported historically as a probiotic drink with great potential in health promotion, as well as being a safe and inexpensive food, easily produced at home. Regular consumption of kefir has been associated with improved digestion and tolerance to lactose, antibacterial effect, hypocholesterolaemic effect, control of plasma glucose, anti-hypertensive effect, anti-inflammatory effect, antioxidant activity, anti-carcinogenic activity, anti-allergenic activity and healing effects. A large proportion of the studies that support these findings were conducted in vitro or in animal models. However, there is a need for systematic clinical trials to better understand the effects of regular use of kefir as part of a diet, and for their effect on preventing diseases. Thus, the present review focuses on the nutritional and microbiological composition of kefir and presents relevant findings associated with the beneficial effects of kefir on human and animal health.

Antimicrobial potential and gustatory perception of chlorhexidine gluconate mouthwashes with or without alcohol after a single rinse - a randomized controlled crossover clinical trial.

OBJECTIVE: The aim of this double-blind randomized clinical trial was to assess whether the presence of alcohol in chlorhexidine gluconate mouthwashes influences their antimicrobial potential against salivary bacteria in young adults. Additionally, the taste perception was assessed. MATERIALS AND METHODS: In a randomized crossover design, 20 participants (17 women and three men; aged 18-38 years old) rinsed with the 0.12% chlorhexidine gluconate with (CHX+) or without alcohol (CHX-) for 1 min. Sterile flavoured-mint physiological saline was used as control solution. All participants rinsed with the assigned products only once with a period of at least 7 days of washout in between. For antimicrobial potential assay, stimulated saliva samples were collected from participants and had their total viable bacteria determined before and after each rinse. For taste perception assay, a visual analogue scale (VAS) was used to evaluate the taste perception after each rinse. Friedman followed by Wilcoxon tests and Bonferroni correction were performed. A P-value <0.017 was considered as statistically significant. RESULTS: The median per cent reduction in groups CHX+ and CHX- was 16.07 and 12.87, respectively. No statistically significant difference was found between these groups (P = 0.09). Regarding the gustatory perception, the VAS median values in groups CHX+ and CHX- were 3.50 and 5.50. No statistically significant difference was found in this outcome (P = 0.052). CONCLUSIONS: The presence of the alcohol on the formulation of gluconate chlorhexidine mouthwashes does not seem to interfere with their antimicrobial potential and with their taste perception.

Eficacia antimicrobiana del primer ortodóncico adicionado con nanopartículas de plata: Estudio transversal in vitro / Antimicrobial efficacy of orthodontic primer added with silver nanoparticles: Cross-sectional in vitro study

Se evaluó la eficacia antimicrobiana de las nanopartículas de plata (NPsAg) incorporadas al adhesivo (primer) colocado en el esmalte dental adyacente a la aparatología ortodóncica fija (brackets). Se realizó un estudio experimental in vitro en 40 premolares, los cuales se dividieron en dos grupos con brackets, uno cementado con primer convencional y otro adicionado con NPsAg; se colocaron en medios de cultivo, previamente inoculados con Streptococcus mutans, y se tomaron muestras para hacer cultivos y conteo de unidades formadoras de colonias (UFC) al día 1, 15 y 30. Se observó una disminución de la presencia de Streptococcus mutans en las muestras a los 15 días de colocado el primer con la agregación de nanopartículas, aunque tal efecto se redujo a los 30 días. Esta reducción del efecto de las nanopartículas puede deberse a la inexistencia de limpieza mecánica, lo cual favoreció la agregación bacteriana sobre el biofilm, afectando su efecto antimicrobiano. Esto sugiere la necesidad de realizar estudios in vivo que permitan observar el comportamiento de los biomateriales en el medio bucal. Las NPsAg agregadas al primer resultan una herramienta eficaz para prevenir la desmineralización del esmalte alrededor de la aparatología ortodóncica fija.

The antimicrobial efficacy of the silver nanoparticles (NPsAg), incorporated into the adhesive (primer) placed in the enamel adjacent to fixed orthodontic appliances (brackets), was evaluated. An experimental study was performed on 40 premolars in vitro, which were divided into two groups with brackets, one cemented with conventional primer and another added with NPsAg, placed in culture media previously inoculated with Streptococcus mutans, and sampled for culturing and counting colony forming units (UFC) on days 1, 15 and 30. A decrease in the presence of Streptococcus mutans in the samples after 15 days with nanoparticle aggregation was observed, and a reduction in the effect of said nanoparticles after 30 days. This reduction of the nanoparticles effects can be due to the absence of mechanical cleaning, which favored the bacterial aggregation on the biofilm, affecting its antimicrobial effect. This suggest the need for realizing studies in “vivo” which will allow the observation of the behavior of the biometals on the buccal medium. The NPsAg added to the primer are an effective tool to prevent the demineralization of the enamel around the fixed orthodontic appliances.

Determinación de la concentración de Mycobacterium por espectrofotometría / Determination of Mycobacterium fortuitum concentration by spectrophotometry / Determinação da concentração de Mycobacterium fortuitum através da espectrofotometria

Mycobacterium fortuitum es agente causante de enfermidad oportunista en humanos y animales. Es un agente biológico modelo para estudios experimentales que sustituy Mycobacterium bovis, que es más patógeno. Este estudio presenta una metodología alternativa para el recuento de unidades formadoras de colonias por mililitro de inóculo para determinar la concentración de Mycobacterium fortuitum usando espectrofotometría. Catorce muestras se utilizaron Mycobacterium fortuitum, cultivadas en Lowesntein-Jensen, ocho de ellos de siete días de cultivo, y la otra entre 8 y 14 días en la cultura. Todas las muestras se colocaron en placas y se incubaron a 37o.C durante 7 días en un invernadero. De cada muestra se hicieron lecturas las variables de absorbancia (Abs) y transmitancia (T%) en un espectrofotómetro, a una longitud de onda de 560 nm y 600 nm. La comparación de los valores de UFC, ABS y T% por análisis de regresión lineal simple, el estadístico SAS versión 8.2 del software, hubo una fuerte evidencia estadística de que el aumento del valor de transmitancia se asocia con la disminución en el valor de UFC chapado, siguiendo el modelo matemático: LOG10 (UFC) = 21,012 - 0,1936 * transmitancia, con p = 0,0025 y una repetibilidad de más de 80%.

Mycobacterium fortuitum is an opportunistic agent which causes disease in human and animals. It is also a biological model for experimental studies instead of using Mycobacterium bovis, which is more pathogenic. This work presents an alternative methodology using spectrophotometry to count colony forming units (CFU) per milliliter of inoculum, in order to determinate Mycobacterium fortuitum concentration. Fourteen Mycobacterium fortuitum samples were cultivated in Lowenstein-Jensen culture media, considering that eight of them were seven days old cultures and the others were between eight and 14 days old. All samples were seeded and incubated at 37o.C for 7 days in an incubator. For each sample, the variables absorbance (Abs) and transmitance (T%) were read with an spectrophotometer and wave length of 560nm and 600nm. When the values of CFU, Abs and T% were compared through simple linear regression analysis and using the statistic software SAS Version 8.2., it was observed strong statistical evidence that the increase of transmitance value is associated to the decrease of CFU plate values, according to the mathematic model: LOG10 (CFU) = 21.012 - 0.1936*Transmitance, and p value = 0.0025 and a repeatability over 80%.

O Mycobacterium fortuitum é um agente oportunista causador de doença em humanos e animais. Além disso, é um modelo biológico para estudos experimentais em substituição ao Mycobacterium bovis, que é mais patogênico. Este estudo apresenta metodologia alternativa à contagem de unidades formadoras de colônia por mililitro de inóculo, para determinar a concentração do Mycobacterium fortuitum utilizando espectrofotometria. Utilizaram-se 14 amostras de Mycobacterium fortuitum, cultivadas em meio Lowesntein-Jensen, sendo oito delas com sete dias de cultivo e as demais entre oito e 14 dias de cultivo. Todas as amostras foram semeadas e incubadas a 37o.C por 7 dias em estufa. Fizeram-se, de cada amostra, leituras das variáveis absorbância (Abs) e transmitância (T%) em espectrofotômetro, nos comprimentos de onda de 560nm e 600nm. Comparando-se os valores obtidos de UFC, Abs e T% por meio da análise de regressão linear simples, pelo programa estatístico SAS versão 8.2, observou-se forte evidência estatística que o aumento do valor da transmitância está associado com o decréscimo do valor de UFC em placas, seguindo o modelo matemático: LOG10 (UFC) = 21.012 - 0.1936*Transmitância, com valor de p = 0,0025 e uma repetibilidade de mais de 80%.

Determinación de la concentración de Mycobacterium por espectrofotometría / Determination of Mycobacterium fortuitum concentration by spectrophotometry / Determinação da concentração de Mycobacterium fortuitum através da espectrofotometria

Mycobacterium fortuitum es agente causante de enfermidad oportunista en humanos y animales. Es un agente biológico modelo para estudios experimentales que sustituy Mycobacterium bovis, que es más patógeno. Este estudio presenta una metodología alternativa para el recuento de unidades formadoras de colonias por mililitro de inóculo para determinar la concentración de Mycobacterium fortuitum usando espectrofotometría. Catorce muestras se utilizaron Mycobacterium fortuitum, cultivadas en Lowesntein-Jensen, ocho de ellos de siete días de cultivo, y la otra entre 8 y 14 días en la cultura. Todas las muestras se colocaron en placas y se incubaron a 37o.C durante 7 días en un invernadero. De cada muestra se hicieron lecturas las variables de absorbancia (Abs) y transmitancia (T%) en un espectrofotómetro, a una longitud de onda de 560 nm y 600 nm. La comparación de los valores de UFC, ABS y T% por análisis de regresión lineal simple, el estadístico SAS versión 8.2 del software, hubo una fuerte evidencia estadística de que el aumento del valor de transmitancia se asocia con la disminución en el valor de UFC chapado, siguiendo el modelo matemático: LOG10 (UFC) = 21,012 - 0,1936 * transmitancia, con p = 0,0025 y una repetibilidad de más de 80%.(AU)

Mycobacterium fortuitum is an opportunistic agent which causes disease in human and animals. It is also a biological model for experimental studies instead of using Mycobacterium bovis, which is more pathogenic. This work presents an alternative methodology using spectrophotometry to count colony forming units (CFU) per milliliter of inoculum, in order to determinate Mycobacterium fortuitum concentration. Fourteen Mycobacterium fortuitum samples were cultivated in Lowenstein-Jensen culture media, considering that eight of them were seven days old cultures and the others were between eight and 14 days old. All samples were seeded and incubated at 37o.C for 7 days in an incubator. For each sample, the variables absorbance (Abs) and transmitance (T%) were read with an spectrophotometer and wave length of 560nm and 600nm. When the values of CFU, Abs and T% were compared through simple linear regression analysis and using the statistic software SAS Version 8.2., it was observed strong statistical evidence that the increase of transmitance value is associated to the decrease of CFU plate values, according to the mathematic model: LOG10 (CFU) = 21.012 - 0.1936*Transmitance, and p value = 0.0025 and a repeatability over 80%.(AU)

O Mycobacterium fortuitum é um agente oportunista causador de doença em humanos e animais. Além disso, é um modelo biológico para estudos experimentais em substituição ao Mycobacterium bovis, que é mais patogênico. Este estudo apresenta metodologia alternativa à contagem de unidades formadoras de colônia por mililitro de inóculo, para determinar a concentração do Mycobacterium fortuitum utilizando espectrofotometria. Utilizaram-se 14 amostras de Mycobacterium fortuitum, cultivadas em meio Lowesntein-Jensen, sendo oito delas com sete dias de cultivo e as demais entre oito e 14 dias de cultivo. Todas as amostras foram semeadas e incubadas a 37o.C por 7 dias em estufa. Fizeram-se, de cada amostra, leituras das variáveis absorbância (Abs) e transmitância (T%) em espectrofotômetro, nos comprimentos de onda de 560nm e 600nm. Comparando-se os valores obtidos de UFC, Abs e T% por meio da análise de regressão linear simples, pelo programa estatístico SAS versão 8.2, observou-se forte evidência estatística que o aumento do valor da transmitância está associado com o decréscimo do valor de UFC em placas, seguindo o modelo matemático: LOG10 (UFC) = 21.012 - 0.1936*Transmitância, com valor de p = 0,0025 e uma repetibilidade de mais de 80%.(AU)