Bacterial colonization of composite resins used with direct technique: a brief review

In restorative dentistry, the use of composite resins with direct technique for the replacement of missing tooth structure is very common. One drawback is that surface roughness allows the adherence of microorganisms and the formation of dental plaque, being the polishing technique a key stage in the restoration process. The aim of this paper is to review the process of bacterial colonization of composite resins used with direct technique. According to in vitro studies, bac-terial adhesion on microhybrid composite resins is 3.91 ± 0.52 UFC and on nanohybrid is 3.34 ± 0.74 UFC. Resins with particle size of 2.5 micrometers contained a greater volume of biofilms and enabled adhesion of S. mutans; in turn, resins with particle size of 0.1 to 0.4 micrometers showed lower bacterial adherence. As summary, the degree of bacterial colonization depends on hygiene, polishing technique and composition of restorative material: the bigger the particle size, the greater the adhesion of bacterial plaque.

Association between Streptococcus mutanslevels and severity of caries in Ecuadorian schoolchildren aged 6 to 10 years

Dental caries is a multifactorial, infectious and communicable disease, and Streptococcus mutans is the key microorganism related to this pathology. The objective of this study was to evaluate the association between the levels of Streptococcus mutans and caries in schoolchildren. Descriptive, cross-sectional study conducted on 100 schoolchildren aged 6 to 10 years from the Unidad Educativa Checa Cuenca, Ecuador. ICDAS index and odontogram were used to measure the prevalence and severity of caries. For the identification and quantification of Streptococcus mutans, dental plaque samples were used for cultivation and biochemical tests (MicroScan). The results were analyzed statistically using absolute and relative frequencies, for bivariate analysis Chi-squared test and Fisher's Test (p <0.05) were used. 96% of the schoolchildren presented dental caries, 69% of them were children aged 8 to 10 years, the prevalence of caries was higher in females reaching 57%. High (60,000UFC/ml) and very high (70,000UFC/ml) levels of Streptococcus mutans were found on schoolchildren aged 8 to 10 years reaching 22% and 8%, respectively (p =0.005). Regarding sex, high (60,000UFC/ml) as well as very low (0- 20,000UFC/ml) levels of Streptococcus mutans appeared without difference by sex (p = 0.355). Schoolchildren without caries presented a low count of Streptococcus mutans (0 -20,000 UFC/ml), children with caries presented variable levels of Streptococcus mutans, although higher than 20,000UFC/ml (p <0.001). Conclusion: there is a high prevalence of caries in the school population with high levels of Streptococcus mutans.

Prevalence of temporomandibular disorders in a sample of Ecuadorian elderly

The aim of this study was to determine the prevalence of temporomandibular disorders ( TMDs) in a sample of Ecuadorian older adults in 2018. This is a cross-sectional study, which was conducted with a sample of 143 older adults of both sexes of the "Senderito de Amor" Elderly Home. The evaluation instrument was the Helkimo index, with the following parameters: presence of muscle pain, difficulty in opening and closing movement, joint pain, joint noises, limitation of mouth opening, limitation of lateral movement, and propulsion and deviation of the jaw. Overall, 88.8% of the population had TMDs, with 85.7% in the group of 60­70 years, 81.8% in the group of 71­80 years, 96.7% in those over 80 years, and 81.0% men and 92.1% women. Statistically significant differences were found by age (p = 0.035), but not by sex (p = 0.055). The most frequent signs and symptoms were joint noise (82.5%), followed by deviation of the jaw during opening (60.1%), reduction of the mouth opening (41.3%), difficulty of opening movements and closure (35.0%), reduction in movements of laterality and propulsion (29.4%), joint and muscle pain (24.5%), muscle pain (18.9%), and joint pain (16.8%). In conclusion, there is a high prevalence of temporomandibular disorders in older adults, and the most frequent signs and symptoms were joint sounds and deviation of the jaw during the mouth opening

Percepción de los estudiantes de enfermería sobre el ambiente de aprendizaje durante sus prácticas clínicas / Perception of the nursing students on the environments of learning during their clinical practices

Introducción: El presente trabajo se elaboró después de haber recopilado y analizado una serie de estudios, se observó que existen pocas evidencias sobre la percepción que tienen los estudiantes acerca del ambiente de aprendizaje durante sus prácticas; por tal motivo surge la necesidad de indagar acerca de este tema. Materiales y Métodos: Cuali-cuantitativo de tipo fenomenológico descriptivo transversal, se utilizó el instrumento creado por la profesora Nancy Navarro H. del Dpto. de Obstetricia y Ginecología de la Facultad de Medicina llamado “instrumento de evaluación de aprendizaje clínico”, el cual tiene como objetivo evaluar la percepción de los estudiantes de sus aprendizajes clínicos. Resultados y Discusión: Los estudiantes refieren que algunos tutores o docentes no van acordes con los objetivos del plan de experiencia practica y solicitan demasiados productos de aprendizaje en poco tiempo de práctica, dando origen a que el estudiante ocupe la mayoría de tiempo a escribir el proceso de atención en enfermería y dediquen poco tiempo a la ejecución en el paciente, lo anterior causado por el desbalance en la organización del tiempo. Conclusiones: De acuerdo a los resultados arrojados en la presente investigación, se llegó al desenlace que las opiniones en cuanto a la percepción de los estudiantes de la Facultad de Enfermería y Obstetricia (FAEO) varia, de acuerdo a las dimensiones: organización de los programas, práctica docente, ambiente de aprendizaje y experiencia clínica, estuvieron parcialmente de acuerdo, mientras que en la dimensión rol del estudiante, estuvieron totalmente de acuerdo.

Introductions: The present work was developed after having compiled and analyzed a series of studies, where it was noted that there is little evidence on the perception of the students about the learning environment during their practices, therefore it is necessary to inquire about this topic. Materials and Methods: Quail- quantitative of type fenomenológico descriptive transverse used the instrument created by teacher Nancy Navarro H. of the Department of obstetrics and Gynecology of the Faculty of medicine called” evaluation of clinical learning instrument”, which it is intended to evaluate the perception of the students of his clinical learnings. Results and Discussions: Students relate that some tutors and teachers are not consistent with the objectives of the plan of experience practice and asked too many products of learning in a short time of practices by resulting in the student engages in drafting the process of nursing in a textual manner and not in the implementation of the process to the patient this by the urgency of time. Conclusions: According to results in the present investigation, it reaches the conclusion that the views on the perception of the students of the Faculty of nursing and obstetrics varies, according to the dimensions; Organization of the programs, practical teaching, environment for learning and clinical experience, agreed partially, while in the role of student dimension, they agreed totally.

Tyl1a, a TDP-6-deoxy-D-xylo-4-hexulose 3,4-isomerase from Streptomyces fradiae: structure prediction, mutagenesis and solvent isotope incorporation experiments to investigate reaction mechanism.

Understanding the structure and mechanism of sugar nucleotide processing enzymes is invaluable in the generation of designer enzymes for biotransformation, for instance, in connection with engineering antibiotic glycosylation. In this study, homology modelling and mechanistic comparison to the structurally related RmlC epimerase family has been used to identify and assign functions to active-site residues in the Tyl1a-catalysed keto-sugar nucleotide isomerisation process. Tyl1a His63 is implicated as the base that initiates the isomerisation process by substrate C-3 deprotonation, with Arg109 stabilising the resulting enolate. Subsequent O-3 deprotonation (potentially by His65) and C-4 protonation (potentially by Tyr49) complete the isomerisation process.

Characterisation of Streptomyces spheroides NovW and revision of its functional assignment to a dTDP-6-deoxy-D-xylo-4-hexulose 3-epimerase.

Characterisation of recombinant Streptomyces spheroides NovW in vitro suggests that it is not a kinetically competent dual action dTDP-6-deoxy-d-xylo-4-hexulose 3,5-epimerase, but possesses only significant 3-epimerase activity.

A practical total synthesis of hapalosin, a 12-membered cyclic depsipeptide with multidrug resistance-reversing activity, by employing improved segment coupling and macrolactonization.

A practical total synthesis of hapalosin, a compound with multidrug resistance-reversing activity, has been carried out using an unprecedented macrolactonization strategy. One of the features of the new approach is the straightforward and fully stereocontrolled access to the key gamma-amino beta-hydroxy carboxylic acid subunit via an efficient acetate aldol addition reaction with N-methyl alpha-aminoaldehydes, which relies on a camphor-derived chiral lithium acetate enolate reagent. The scope of this aldol reaction is investigated and its potential application to the synthesis of other structurally related, biologically relevant compounds illustrated. Remarkably, the chiral tether in the resulting gamma-amino aldol adducts sterically protect the carbonyl group, thus avoiding intramolecular cyclization during the amino group deprotection and the subsequent segment coupling event. After successful segment coupling and smooth, clean release of the chiral auxiliary, a new macrolactonization protocol, based on the principle of double activation of both reactive sites, is applied, which leads to the 12-membered macrolactone hapalosin in unprecedented chemical efficiency.

La percepción salud/enfermedad en madres de niños menores de cinco años en un barrio marginal de Orán, provincia de Salta, Argentina / Health disease perception by mothers in charge of smaller than 5 years-old children at a marginal fuarter in the city of Oran, province of Salta

En la presente investigación se relevó, a partir de un estudio cualitativo en un barrio marginal de Orán, Pcia. de Salta, la percepción que sobre salud-enfermedad desarrollaron madres con niños menores a cargo, describiendo la multiplicidad y complejidad de factores que intervienen en ella

La percepción salud/enfermedad en madres de niños menores de cinco años en un barrio marginal de Orán, provincia de Salta, Argentina / Health disease perception by mothers in charge of smaller than 5 years-old children at a marginal fuarter in the city of Oran, province of Salta

En la presente investigación se relevó, a partir de un estudio cualitativo en un barrio marginal de Orán, Pcia. de Salta, la percepción que sobre salud-enfermedad desarrollaron madres con niños menores a cargo, describiendo la multiplicidad y complejidad de factores que intervienen en ella (AU)

Tratamiento de úlceras infectadas en pacientes con Diabetes Mellitus / Treatment of infected ulcers in Diabetic patients

Se estudiaron 40 pacientes con diagnóstico de Diabetes Mellitus y úlcera de miembros inferiores. Se demostró infección en 22 pacientes siendo los gérmenes más frecuentes: Gram positivos (Staphylococcus aureus: 7) y Gram negativos (Enterobacter aglomerans: 5 y Klebsiella pneumoniae: 4). Los antibióticos más utilizados fueron: enoxacina con una mejoría en el 83 por ciento del proceso infeccioso (Gram negativos y/o Staphylococcus aureus) y la dicloxacicilina con un 90 por ciento (Staphylococcus aureus)