In vitro evaluation of the osteogenic and antimicrobial potential of porous wollastonite scaffolds impregnated with ethanolic extracts of propolis.

Context: The development of porous devices using materials modified with various natural agents has become a priority for bone healing processes in the oral and maxillofacial field. There must be a balance between the proliferation of eukaryotic and the inhibition of prokaryotic cells to achieve proper bone health. Infections might inhibit the formation of new alveolar bone during bone graft augmentation. Objective: This study aimed to evaluate the in vitro osteogenic behavior of human bone marrow stem cells and assess the antimicrobial response to 3D-printed porous scaffolds using propolis-modified wollastonite. Methodology: A fractional factorial design of experiments was used to obtain a 3D printing paste for developing scaffolds with a triply periodic minimal surface (TPMS) gyroid geometry based on wollastonite and modified with an ethanolic propolis extract. The antioxidant activity of the extracts was characterized using free radical scavenging methods (DPPH and ABTS). Cell proliferation and osteogenic potential using Human Bone Marrow Stem Cells (bmMSCs) were assessed at different culture time points up to 28 days. MIC and inhibition zones were studied from single strain cultures, and biofilm formation was evaluated on the scaffolds under co-culture conditions. The mechanical strength of the scaffolds was evaluated. Results: Through statistical design of experiments, a paste suitable for printing scaffolds with the desired geometry was obtained. Propolis extracts modifying the TPMS gyroid scaffolds showed favorable cell proliferation and metabolic activity with osteogenic potential after 21 days. Additionally, propolis exhibited antioxidant activity, which may be related to the antimicrobial effectiveness of the scaffolds against S. aureus and S. epidermidis cultures. The mechanical properties of the scaffolds were not affected by propolis impregnation. Conclusion: These results demonstrate that propolis-impregnated porous wollastonite scaffolds might have the potential to stimulate bone repair in maxillofacial tissue engineering applications.

Antibacterial and osteoinductive properties of wollastonite scaffolds impregnated with propolis produced by additive manufacturing.

Biocompatible ceramic scaffolds offer a promising approach to address the challenges in bone reconstruction. Wollastonite, well-known for its exceptional biocompatibility, has attracted significant attention in orthopedics and craniofacial fields. However, the antimicrobial properties of wollastonite have contradictory findings, necessitating further research to enhance its antibacterial characteristics. This study aimed to explore a new approach to improve in vitro biological response in terms of antimicrobial activity and cell proliferation by taking advantage of additive manufacturing for the development of scaffolds with complex geometries by 3D printing using propolis-modified wollastonite. The scaffolds were designed with a TPMS (Triply Periodic Minimal Surface) gyroid geometric shape and 3D printed prior to impregnation with propolis extract. The paste formulation was characterized by rheometric measurements, and the presence of propolis was confirmed by FTIR spectroscopy. The scaffolds were comprehensively assessed for their mechanical strength. The biological characterization involved evaluating the antimicrobial effects against Staphylococcus aureus and Staphylococcus epidermidis, employing Minimum Inhibitory Concentration (MIC), Zone of Inhibition (ZOI), and biofilm formation assays. Additionally, SaOs-2 cultures were used to study cell proliferation (Alamar blue assay), and potential osteogenic was tested (von Kossa, Alizarin Red, and ALP stainings) at different time points. Propolis impregnation did not compromise the mechanical properties of the scaffolds, which exhibited values comparable to human trabecular bone. Propolis incorporation conferred antibacterial activity against both Staphylococcus aureus and Staphylococcus epidermidis. The implementation of TPMS gyroid geometry in the scaffold design demonstrated favorable cell proliferation with increased metabolic activity and osteogenic potential after 21 days of cell cultures.

Frequency of polymorphisms in the CYP2C9, VKORC1, and CYP4F2 genes related to the metabolism of Warfarin in healthy donors from Cali, Colombia.

Alleles in the VKORC1, CYP2C9, and CYP4F2 genes can influence Warfarin dose requirement. We aimed to determine the frequency of the polymorphisms in these genes in healthy individuals from Cali, Colombia. Observational study where total blood was collected from 107 healthy donors who attended a higher educational institution in Cali, Colombia. Sanger sequencing of exons 2, 3, 5, and 7 of the CYP2C9 gene; the common promoter region of CYP (rs12777823); exon 11 of CPY4F2 and the polymorphism c.-1639G > A in the VKORC1 gene promoter was performed. CYP2C9*2, CYP2C9*3, CYP2C9*8, CYP2C9*9, CYP2C9*11, CYP4F2*3, rs12777823, and VKORC1*2 were detected. The latter had the highest frequency with 80 (74.8%) participants in a heterozygous or homozygous state. The least frequent allele was CYP2C9*11 with only 1 carrier. Combined haplotypes (VKORC1 *1/*2 or *2/*2 and CYP2C9 *1/*2 or *2/*2) were identified in 14 (13.7%) subjects. Both frequencies found in the VKORC1 and CYP2C9 alleles were similar to the ones reported for Latin Americans of European and Native American Ancestry. VKORC1*2 allele, the main genetic contributor to Warfarin dosing requirement, was the variant with the highest frequency (74.8% subjects, with a frequency of the alternative allele (A) of 50%). Our findings provide researchers with a greater insight regarding the frequency of common polymorphisms that affect anticoagulation treatment in the Cali (Colombia) population.

Effects of Propolis Impregnation on Polylactic Acid (PLA) Scaffolds Loaded with Wollastonite Particles against Staphylococcus aureus, Staphylococcus epidermidis, and Their Coculture for Potential Medical Devices.

Several diseases and injuries cause irreversible damage to bone tissues, which may require partial or total regeneration or replacement. Tissue engineering suggests developing substitutes that may contribute to the repair or regeneration process by using three-dimensional lattices (scaffolds) to create functional bone tissues. Herein, scaffolds comprising polylactic acid and wollastonite particles enriched with propolis extracts from the Arauca region of Colombia were developed as gyroid triply periodic minimal surfaces using fused deposition modeling. The propolis extracts exhibited antibacterial activity against Staphylococcus aureus (ATCC 25175) and Staphylococcus epidermidis (ATCC 12228), which cause osteomyelitis. The scaffolds were characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy, differential scanning calorimetry, contact angle, swelling, and degradation. Their mechanical properties were assessed using static and dynamic tests. Cell viability/proliferation assay was conducted using hDP-MSC cultures, while their bactericidal properties against monospecies cultures (S. aureus and S. epidermidis) and cocultures were evaluated. The wollastonite particles did not affect the physical, mechanical, or thermal properties of the scaffolds. The contact angle results showed that there were no substantial differences in the hydrophobicity between scaffolds with and without particles. Scaffolds containing wollastonite particles suffered less degradation than those produced using PLA alone. A representative result of the cyclic tests at Fmax = 450 N showed that the maximum strain reached after 8000 cycles is well below the yield strain (i.e., <7.5%), thereby indicating that even under these stringent conditions, these scaffolds will be able to work properly. The scaffolds impregnated with propolis showed a lower % of cell viability using hDP-MSCs on the 3rd day, but these values increased on the 7th day. These scaffolds exhibited antibacterial activity against the monospecies cultures of S. aureus and S. epidermidis and their cocultures. The samples without propolis loads did not show inhibition halos, whereas those loaded with EEP exhibited halos of 17.42 ± 0.2 mm against S. aureus and 12.9 ± 0.5 mm against S. epidermidis. These results made the scaffolds possible bone substitutes that exert control over species with a proliferative capacity for the biofilm-formation processes required for typical severe infectious processes.

A Patient with Bone Fragility, Multiple Fractures, Osteosarcoma, and the Variant c.143A>G in the IFITM5 Gene: A Case Report.

Osteogenesis imperfecta (OI) is a group of genetic skeletal disorders, with a prevalence of 1 in 15,000-20,000 births. OI type V has been described in approximately 150 cases and all patients carry the variant (c.-14C> T) in the IFITM5 gene. However, two other variants, p.S40L and p.N48S have been reported in this gene, leading to clinical phenotypes different from OI type V. Here we described a patient with multiple bone fractures, scoliosis, skull alteration (plagiocephaly), bone deformation, bone rickets, and intramedullary epithelioid osteosarcoma that bears the recently reported heterozygous variant c.143A>G (p.N48S) in the IFITM5 gene. This case supports the pathogenicity of this new variant in the IFITM5 gene and adds information regarding its clinical phenotype.

Mowat-Wilson Syndrome as a Differential Diagnosis in Patients with Congenital Heart Defects and Dysmorphic Facies.

Mowat-Wilson syndrome is a rare, autosomal dominant neurodevelopmental disorder characterized by distinctive facial gestalt and intellectual disability that is often associated with microcephaly, seizures and multiple congenital anomalies, mainly heart defects. More than 350 patients and 180 genetic variants in the ZEB2 gene, have been reported with an estimated frequency of 1 per 70,000 births. Here we report a Colombian female patient with facial gestalt, intellectual disability, microcephaly, congenital heart defects, hypothyroidism and middle ear defect associated with the nonsense pathogenic variant c.2761C>T (p.Arg921Ter) in the ZEB2 gene. This case contributes to the understanding of the clinical complications and the natural history of this complex and clinically heterogeneous disorder but also to the awareness that patients with heart congenital defects and dysmorphic facies may present an underlying genetic disorder.

Neurofibromatosis Type 1 and Hypospadias in a Male 46, XY with a Mutation in the NF1 Gene and a Mutation in NR5A1.

Neurofibromatosis type 1 is one of the most common genetic autosomal dominant disorders described, with a prevalence of 1 in 2000 to 1 in 3000 individuals. It is characterized by skin, nerves, and bone abnormalities. Non-related to NF1, hypospadias is a displacement in the urethral opening which in the majority of patients has an idiopathic cause. Here, we describe a patient with neurofibromatosis type 1, hypospadias, and unilateral cryptorchidism. The heterozygous variants c.6789_6792delTTAC, p.(Tyr2264Thrfs*5) and c.140A>G, p.(Tyr47Cys) were found in the NF1 and NR5A1 genes, respectively. This case contributes to the phenotypical characterization of patients with NF1 but also with hypospadias caused by a mutation in the NR5A1 gene, which usually leads to severe sex disorders.

2q37 deletion syndrome in a Colombian patient with macrocephaly: a case report.

BACKGROUND: 2q37 deletion syndrome is a rare autosomal dominant disorder caused by deletions in the 2q37 cytobands leading to developmental delay, intellectual disability, behavioral abnormalities and dysmorphic craniofacial features with more than 115 patients described worldwide. CASE PRESENTATION: We describe a Colombian 3-year-old patient with verbal communication delay, umbilical hernia, facial dysmorphic features, hypotonia, and macrocephaly with normal magnetic resonance imaging. Microarray-based comparative genomic hybridization revealed a 5.9 Mb deletion in the 2q37.2 and 2q37.3 regions, eliminating 60 protein-coding genes in one of her chromosomes 2 and allowing the diagnosis of 2q37 deletion syndrome in this patient. Therapeutic interventions so far were the surgical correction of the umbilical hernia. CONCLUSIONS: Genetic tests are important tools for the diagnosis of clinically complex and infrequent conditions but also for timely diagnosis that allows appropriate surveillance, interventions, and genetic counseling. This case also provides information for expanding the phenotypical and genetic characterization of 2q37 deletion syndrome.

B Cell Subsets in Colombian Adults with Predominantly Antibody Deficiencies, Bronchiectasis or Recurrent Pneumonia.

AIM: To evaluate and describe lymphocyte populations' and B cell subsets' frequencies in patients presenting with Predominantly antibody deficiencies (PAD) and diagnosed with bronchiectasis or recurrent pneumonia seen in Cali (Colombian Southwest region). MATERIALS AND METHODS: 16 subjects with PAD, 20 subjects with pulmonary complications (bronchiectasis or recurrent pneumonia) and 20 healthy donors (HD). Controls and probands between 14 and 64 years old, regardless of gender were included. Lymphocyte populations (T, B and NK cells) and B cell subsets were evaluated in peripheral blood mononuclear cells using flow cytometry, T/B/NK reagent and the pre-germinal center antibody panel proposed by the EUROflow consortium were used. EUROclass and the classification proposed by Driessen et al. were implemented. RESULTS: CVID patients exhibited increase absolute numbers of CD8+ T cells and reduce NK cells as compare with HD, other PAD cases or pulmonary complications. PAD B cell subsets were disturbed when compared to the age range-matched healthy donors. Among B cell subsets, the memory B cell compartment was the most affected, especially switched memory B cells. Four participants were classified as B- and two CVID as smB-Trnorm and smB-21low groups according to EUROclass classification. The most frequent patterns proposed by Driessen et al. were B cell production and germinal center defect. CONCLUSIONS: B cell subsets, especially memory B cells, are disturbed in PAD patients from Southwestern Colombia. To the best of our knowledge this is the most comprehensive study of B cell subsets in Colombian adults.

A Novel POGZ Variant in a Patient with Intellectual Disability and Obesity.

White-Sutton syndrome is a rare type of autosomal dominant neurodevelopmental disorder caused by mutations, mostly de novo, in the POGZ gene. No more than 120 patients have been described so far in the literature. Common clinical manifestations include intellectual disability, developmental delay, autism spectrum disorder, other behavioral abnormalities, sleeping problems, hyperactivity and visual problems. We describe a 20-year-old male patient from Colombia who presented with delayed psychomotor development, intellectual disability, obesity, sleep difficulties, hypotonia, hypogonadism, gynecomastia, visual abnormalities and several facial dysmorphisms. Genetic testing showed a novel heterozygous frameshift variant (c.3308del; p.Leu1103Profs*19) in the POGZ gene (NM_015100.3). This is the first report of a diagnosed patient with WHSUS in Colombia.

Case report: Craniofrontonasal syndrome caused by a novel variant in the EFNB1 gene in a Colombian woman.

Craniofrontonasal Syndrome is a very rare dominant X-linked genetic disorder characterized by symptoms such as hypertelorism, craniosynostosis, eye alterations, bifid nose tip, and longitudinal ridging and splitting of nails. Heterozygous females are usually the patients severely affected. To date, clinical or genetic data have not been published for these patients in Colombia. Here we report a female proband with coronal craniosynostosis, hypertelorism, strabismus, rotational nystagmus, high-arched palate, dental crowding, scoliosis, severe pectus excavatum, unilateral breast hypoplasia, and brachydactyly; diagnosed with Craniofrontonasal Syndrome with the novel heterozygous variant c.374A>C (p.Glu125Ala) in the EFNB1 gene. So far, she has been treated with physical therapy and surgical correction of the bifid nose and an umbilical hernia. To the best of our knowledge, this is the first report of a patient with this rare genetic disorder in Colombia, expanding its mutational spectrum and highlighting the importance of genetic evaluation of patients with craniosynostosis and facial dysmorphism.

Functional Classification of Isolated Zygomatic Arch Fracture: New Proposal.

ABSTRACT: Isolated zygomatic arch fractures are common fractures in maxillofacial trauma. These fractures can trigger a functional alteration in the mouth opening and closing. Until now, there is no published classification of an isolated zygomatic arch fracture that contains the presence or not of coronoid impingement. So we propose a new classification that is easy to handle and has the largest number of scenarios that can occur in this type of fracture. The isolated zygomatic arch fracture is classified as Type I: Nondisplaced fractures, Type II: Greenstick fracture with or without coronoid impingement, Type III: Single displaced fracture with or without coronoid impingement, Type IV: Multiple displaced fracture with or without coronoid impingement, Type V: Comminuted fracture with or without coronoid impingement. We consider it to be a comprehensive classification, with general concepts of bone fractures, that can be incorporated into professional daily practice.

New Protocol for Long-Term Results With a Multi-Pulse Nd:YAG Laser for Melasma Treatment: A Descriptive Cohort Study.

BACKGROUND: Melasma is a photoaging condition with a typical clinical and histological pattern under a genetic and epigenetic context. Over the years, many treatments modalities have been proposed including topical agents, oral medication, procedures, and combination treatments aiming at different aspects of the pathogenesis including photodamage, inflammation, vascularity, and pigmentation. Recently, lasers have become an alternative for the treatment of melasma using thermal energy to target, in a selective way, the chromophore found in the skin such as melanin. OBJECTIVE: This study aimed to show how we have implemented a multifactorial approach that not only treats the symptoms but addresses the primary underlying cause of melasma. MATERIALS AND METHODS: Twenty female patients with dermal and mixed melasma were admitted to Medical Art between December 2017 and April 2018 and received a four-step Fotona laser protocol. Clinical evaluation of a clearance percentage of melasma was performed 1 month after the last session by a blinded dermatologist grading the images taken during the study. Follow-up evaluation was performed at 6 and 12 months following the completion of the laser treatment, which was 6 sessions. Patients were also asked following the end of the treatment about their satisfaction, which was evaluated with a 5-point scale. RESULTS: This descriptive cohort study included patients with melasma who underwent the four-step laser protocol treatment at 2-week intervals. The clearance percentage score showed 70% with excellent reduction, 25% with good reduction in appearance of melasma, none of the patients with a fair reduction, and 5% with a poor reduction. The mean score of patient satisfaction was 4,65 ± 0,93 (93%). CONCLUSION: Results of this study indicate that the four-step Fotona laser protocol is a safe and effective treatment option for melasma. J Drugs Dermatol. 2021;20(2):150-154. doi:10.36849/JDD.1221.

Síndrome de burnout y dependencia al alcohol en estudiantes de medicina

RESUMEN Introducción: el síndrome de Burnout es una enfermedad mental causada por el estrés laboral, situación ampliamente asociada con los médicos y otros profesionales de salud, asimismo, el abuso de sustancias y la depresión también son problemas psiquiátricos que están relacionados con este ámbito. Objetivo: identificar la frecuencia de estudiantes de medicina del área clínica de la Universidad Nacional de Asunción con sospecha de Síndrome de Burnout y trastorno de abuso de alcohol. Metodología: estudio observacional, descriptivo, de corte transversal en estudiantes de medicina del área clínica de la Universidad Nacional de Asunción de Paraguay. Se utilizaron encuestas con la prueba de identificación de desórdenes de uso del alcohol (AUDIT-C), el inventario de Maslach y el screening de depresión PHQ-2. Resultados: de las 157 encuestas, el 43,9% cumplió con los criterios de Síndrome de Burnout, el 49% cumplió los criterios de abuso/dependencia de alcohol y el 38,9% tuvo criterios de alta probabilidad de trastorno depresivo mayor, de ellos la mayoría presentó ideación suicida en los últimos 12 meses. Conclusión: los resultados fueron parecidos a los hallados en la literatura, sin embargo, ciertos aspectos fueron mayores en este estudio, como el porcentaje que cumple los criterios de Síndrome de Burnout, abuso de sustancias e ideación suicida. El Síndrome de Burnout y la dependencia al alcohol son frecuentes en estudiantes de medicina y se asocian comúnmente a trastornos depresivos.

ABSTRACT Introduction: Burnout Syndrome is a mental disorder caused by occupational stress, a situation widely prevalent in doctors and other health professionals. Substance abuse and depression are also psychiatric problems that are related to this area. Objective: To identify the frequency of Burnout Syndrome and its association with Alcohol misuse in medical students in their clinical years at the National University of Asunción. Methodology: Observational, descriptive, cross-sectional study in medical students from the clinical area of the National University of Asunción, Paraguay. Surveys were used with the alcohol use disorder identification test (AUDIT-C), the Maslach inventory and the PHQ-2 depression screening. Results: Of the 157 surveys, 43.9% met the criteria for Burnout Syndrome, 49% met the criteria for alcohol misuse / dependence and 38.9% had high probability crite-ria for major depressive disorder. Most of them presented suicidal ideation in the last 12 months. Conclusion: The results were similar to those found in the literature, however, certain aspects were greater in this study, such as the percentage that meets the criteria for Burnout Syndrome, alcohol misuse and suicidal ideation. Burnout Syndrome and alcohol misuse are frequent in medical students and are commonly associated with depressive disorders.

Molecular characterization of Epstein-Barr virus variants detected in the oral cavity of adolescents in Cali, Colombia / [Caracterización molecular de las variantes del virus de Epstein-Barr detectadas en la cavidad oral de adolescentes de Cali, Colombia].

Introduction: The Epstein-Barr virus (EBV) is an ubiquitous and oncogenic virus associated with the development of diseases such as infectious mononucleosis, Burkitt's lymphoma, nasopharyngeal carcinoma, and other neoplasms. Currently, two types are recognized: EBV-1 and EBV-2, which have genetic differences with their EBNA nuclear antigens. Likewise, due to the high degree of heterogeneity and variability found in the LMP1 protein of the virus, variants associated with pathogenesis or specific geographic regions have been described. Objective: To identify and characterize molecularly EBV variants detected in the oral cavity of 84 adolescents in Cali, Colombia. Materials and methods: Conventional PCR amplification, purification, and sequencing of the gen EBNA3C were carried out to typify the virus and the C-ter domain of the LMP1 protein to identify variants. We also conducted a phylogenetic and nucleotide variant analysis of the obtained sequences versus pathogenic or geographic variants reported in GenBank-NCBI. Results: The predominant viral subtype was EBV-1 (79%); 72.6% was grouped with the pathogenic variant Raji, derived from B lymphocytes of a patient with Burkitt>s lymphoma, 13.7% was related to a variant of Mediterranean origin, and 13.7% was not grouped with any of the reference variants. Conclusions: This is the first time that variants of LMP1-EBV have been identified in Cali, Colombia. Additional studies are necessary to characterize the unidentified variant and to determine if it is pathogenic or if it is just an isolate present in the city of Cali.

Introducción. El virus de Epstein-Barr (EBV) es un virus ubicuo y oncogénico, asociado con el desarrollo de enfermedades como la mononucleosis infecciosa, el linfoma de Burkitt, el carcinoma nasofaríngeo y otras neoplasias. Actualmente, se reconocen dos subtipos: EBV-1 y EBV- 2, que tienen diferencias genéticas con sus antígenos nucleares (Epstein-Barr Nuclear Antigens, EBNA). Debido a la gran heterogeneidad y variabilidad encontradas en la proteína LMP1 del virus, se han descrito variantes asociadas con ciertas enfermedades o con regiones geográficas específicas. Objetivo. Identificar y caracterizar molecularmente las variantes del EBV detectadas en la cavidad oral de 84 adolescentes de Cali, Colombia. Materiales y métodos. Se hizo la amplificación por reacción en cadena de la polimerasa (Polymerase Chain Reaction, PCR) convencional, así como la purificación y la secuenciación del gen EBNA3C se realizó para subtipificar el virus y del dominio C-ter de la proteína LMP1 para identificar variantes. Además, se llevó a cabo un análisis filogenético y de variantes nucleotídicas de las secuencias obtenidas comparadas con variantes patogénicas y geográficas reportadas en el GenBank (National Center for Biotechnology Information, NCBI). Resultados. El subtipo viral predominante fue el EBV-1 (79 %); el 72,6 % se agrupó con la variante patogénica Raji, derivada de linfocitos B de un paciente con linfoma de Burkitt; el 13,7 % se relacionó con una variante de origen geográfico del Mediterráneo y otro 13,7 % no se agrupó con ninguna de las variantes de referencia. Conclusiones. Este es el primer estudio que reporta variantes del gen LMP1-EBV en Cali, Colombia. Se requieren nuevos estudios para caracterizar la variante sin identificar y determinar si es patogénica o si es una variante geográfica presente exclusivamente en la ciudad.

Caracterización molecular de las variantes del virus de Epstein-Barr detectadas en la cavidad oral de adolescentes de Cali, Colombia / Molecular characterization of Epstein-Barr virus variants detected in the oral cavity of adolescents in Cali, Colombia

Introducción. El virus de Epstein-Barr (EBV) es un virus ubicuo y oncogénico, asociado con el desarrollo de enfermedades como la mononucleosis infecciosa, el linfoma de Burkitt, el carcinoma nasofaríngeo y otras neoplasias. Actualmente, se reconocen dos subtipos: EBV-1 y EBV- 2, que tienen diferencias genéticas con sus antígenos nucleares (Epstein-Barr Nuclear Antigens, EBNA). Debido a la gran heterogeneidad y variabilidad encontradas en la proteína LMP1 del virus, se han descrito variantes asociadas con ciertas enfermedades o con regiones geográficas específicas. Objetivo. Identificar y caracterizar molecularmente las variantes del EBV detectadas en la cavidad oral de 84 adolescentes de Cali, Colombia. Materiales y métodos. Se hizo la amplificación por reacción en cadena de la polimerasa (Polymerase Chain Reaction, PCR) convencional, así como la purificación y la secuenciación del gen EBNA3C se realizó para subtipificar el virus y del dominio C-ter de la proteína LMP1 para identificar variantes. Además, se llevó a cabo un análisis filogenético y de variantes nucleotídicas de las secuencias obtenidas comparadas con variantes patogénicas y geográficas reportadas en el GenBank (National Center for Biotechnology Information, NCBI). Resultados. El subtipo viral predominante fue el EBV-1 (79 %); el 72,6 % se agrupó con la variante patogénica Raji, derivada de linfocitos B de un paciente con linfoma de Burkitt; el 13,7 % se relacionó con una variante de origen geográfico del Mediterráneo y otro 13,7 % no se agrupó con ninguna de las variantes de referencia. Conclusiones. Este es el primer estudio que reporta variantes del gen LMP1-EBV en Cali, Colombia. Se requieren nuevos estudios para caracterizar la variante sin identificar y determinar si es patogénica o si es una variante geográfica presente exclusivamente en la ciudad.

Introduction: The Epstein-Barr virus (EBV) is an ubiquitous and oncogenic virus associated with the development of diseases such as infectious mononucleosis, Burkitt's lymphoma, nasopharyngeal carcinoma, and other neoplasms. Currently, two types are recognized: EBV-1 and EBV-2, which have genetic differences with their EBNA nuclear antigens. Likewise, due to the high degree of heterogeneity and variability found in the LMP1 protein of the virus, variants associated with pathogenesis or specific geographic regions have been described. Objective: To identify and characterize molecularly EBV variants detected in the oral cavity of 84 adolescents in Cali, Colombia. Materials and methods: Conventional PCR amplification, purification, and sequencing of the gen EBNA3C were carried out to typify the virus and the C-ter domain of the LMP1 protein to identify variants. We also conducted a phylogenetic and nucleotide variant analysis of the obtained sequences versus pathogenic or geographic variants reported in GenBank-NCBI. Results: The predominant viral subtype was EBV-1 (79%); 72.6% was grouped with the pathogenic variant Raji, derived from B lymphocytes of a patient with Burkitt>s lymphoma, 13.7% was related to a variant of Mediterranean origin, and 13.7% was not grouped with any of the reference variants. Conclusions: This is the first time that variants of LMP1-EBV have been identified in Cali, Colombia. Additional studies are necessary to characterize the unidentified variant and to determine if it is pathogenic or if it is just an isolate present in the city of Cali.

Enhanced purification coupled with biophysical analyses shows cross-ß structure as a core building block for Streptococcus mutans functional amyloids.

Streptococcus mutans is an etiologic agent of human dental caries that forms dental plaque biofilms containing functional amyloids. Three amyloidogenic proteins, P1, WapA, and Smu_63c were previously identified. C123 and AgA are naturally occurring amyloid-forming fragments of P1 and WapA, respectively. We determined that four amyloidophilic dyes, ThT, CDy11, BD-oligo, and MK-H4, differentiate C123, AgA, and Smu_63c amyloid from monomers, but non-specific binding to bacterial cells in the absence of amyloid precludes their utility for identifying amyloid in biofilms. Congo red-induced birefringence is a more specific indicator of amyloid formation and differentiates biofilms formed by wild-type S. mutans from a triple ΔP1/WapA/Smu_63c mutant with reduced biofilm forming capabilities. Amyloid accumulation is a late event, appearing in older S. mutans biofilms after 60 hours of growth. Amyloid derived from pure preparations of all three proteins is visualized by electron microscopy as mat-like structures. Typical amyloid fibers become evident following protease digestion to eliminate non-specific aggregates and monomers. Amyloid mats, similar in appearance to those reported in S. mutans biofilm extracellular matrices, are reconstituted by co-incubation of monomers and amyloid fibers. X-ray fiber diffraction of amyloid mats and fibers from all three proteins demonstrate patterns reflective of a cross-ß amyloid structure.

SIM-CIG: A Serious Game to Practice and Improve Clinical Guidelines Adoption Based on Computer-Interpretable Guidelines.

Serious games have been used to increase the accuracy and usege of clinical guidelines during routine clinical practice. This document presents the development of a serious game called SIM-GIC, a video game designed to simulate virtual patients and evaluate the decision making of players based on computer-interpretable clinical guidelines. The system is currently being developed with a content focus on antenatal care guidelines, where a number of obstetric guidelines were coded in XML files.

Detección del virus Epstein Barr en escolares adolescentes en la ciudad de Cali, Colombia / Detection of epstein barr virus in adolescent students in the city of cali, colombia

Objetivo: Detectar el virus Epstein-Barr en estudiantes de secundaria entre los 14 y 17 años de la ciudad de Cali, Colombia y su posible asociación con la edad, sexo y grado escolar. Métodos: Estudio retrospectivo de corte transversal en donde se analizaron 374 muestras de saliva, tomadas entre el año 2015 y 2016, mediante PCR convencional y PCR en Tiempo real. Se evalúo la asociación entre la detección del ADN viral y las características demográficas, además de un análisis de razón de oportunidades para evaluar la medida de la asociación. Resultados: El ADN viral fue detectado en el 45% (167/374) de las muestras orales, encontrándose una presencia viral mayor en los escolares de los grados octavo y noveno (p=0,004); en donde los estudiantes de 14 años presentaron un riesgo de 2,4 veces mayor para la detección del virus (IC 95%:1,12-4,9) en comparación con los estudias de más edad. Conclusión: En el presente estudio se evidencio la exposición del VEB en la cavidad oral de estudiantes de secundaria, lo cual hace necesario que se tomen acciones de vigilancia que permitan monitorear las implicaciones de estos hallazgos en la salud de los escolares.

Objective: To detect the Epstein Barr virus in adolescent students between 14 and 17 years old in the city of Cali, Colombia and its possible association with age, gender and school grade. Methods: Retrospective cross-sectional study where 374 mouthwash samples collected between the years 2015 and 2016 was analyzed through conventional and real-time PCR. Association between viral DNA detection and sociodemographic characteristics were evaluated. The odds ratio analysis was used to assess the extent of this association. Results: The viral DNA was present in 45% (167/374) of the samples, with a higher DNA detection in the students of eighth and ninth grades (p=0.004); where the 14 years old students present a 2.4 times higher risk of detecting the virus (IC 95%: 1,12-4.9) in comparison with older students. Conclusion: In the present study, the Epstein Barr virus exposition in the oral cavity was evidenced, which make necessary to take actions on surveillance that allow monitoring the implications of these fndings in the teenage student's health.