In Silico Selection and In Vitro Evaluation of New Molecules That Inhibit the Adhesion of Streptococcus mutants through Antigen I/II.

Streptococcus mutans is the main early colonizing cariogenic bacteria because it recognizes salivary pellicle receptors. The Antigen I/II (Ag I/II) of S. mutans is among the most important adhesins in this process, and is involved in the adhesion to the tooth surface and the bacterial co-aggregation in the early stage of biofilm formation. However, this protein has not been used as a target in a virtual strategy search for inhibitors. Based on the predicted binding affinities, drug-like properties and toxicity, molecules were selected and evaluated for their ability to reduce S. mutans adhesion. A virtual screening of 883,551 molecules was conducted; cytotoxicity analysis on fibroblast cells, S. mutans adhesion studies, scanning electron microscopy analysis for bacterial integrity and molecular dynamics simulation were also performed. We found three molecules ZINC19835187 (ZI-187), ZINC19924939 (ZI-939) and ZINC19924906 (ZI-906) without cytotoxic activity, which inhibited about 90% the adhesion of S. mutans to polystyrene microplates. Molecular dynamic simulation by 300 nanoseconds showed stability of the interaction between ZI-187 and Ag I/II (PDB: 3IPK). This work provides new molecules that targets Ag I/II and have the capacity to inhibit in vitro the S. mutans adhesion on polystyrene microplates.

Environmental Surveillance of Polioviruses in Armenia, Colombia before Trivalent Oral Polio Vaccine Cessation.

Although acute flaccid paralysis (AFP) surveillance is the "gold standard" for detecting cases of polio, environmental surveillance can provide supplementary information in the absence of paralytic poliomyelitis cases. This study aimed to detect the introduction and/or circulation of wild poliovirus or vaccine-derived polioviruses (VDPV) in wastewater, covering a significant population of Armenia, Colombia, before trivalent oral polio vaccine (OPV) cessation. Between March and September 2015, 24 wastewater samples were collected from eight study sites in eight communes of Armenia, Colombia. Virus detection and characterization were performed using both cell culture (i.e., RD or L20B cells) and RT-PCR. Polioviruses were isolated in 11 (45.8%) of 24 wastewater samples. All isolates were identified as Sabin strains (type 1 = 9, type 3 = 2) by intratypic differentiation. Type 2 poliovirus was not detected in any of the samples. No wild poliovirus or VDPV was detected among the isolates. Non-polio enterovirus was identified in 8.3% (2/24) of the samples. This study revealed the excretion of Sabin poliovirus from OPV-immunized individuals, as well as the absence of VDPV and wild poliovirus in wastewaters of Armenia, Colombia. This confirms that environmental surveillance is an effective method, as an additional support to AFP surveillance, to monitor poliovirus during the OPV-to-IPV (inactivated polio vaccine) transition period.

Inhibitors compounds of the flavivirus replication process.

Flaviviruses are small viruses with single-stranded RNA, which include the yellow fever virus, dengue virus, West Nile virus, Japanese encephalitis virus, tick-borne encephalitis virus, and Zika virus; and are causal agents of the most important emerging diseases that have no available treatment to date. In recent years, the strategy has focused on the development of replication inhibitors of these viruses designed to act mainly by affecting the activity of enzyme proteins, such as NS3 and NS5, which perform important functions in the viral replication process. This article describes the importance of flaviviruses and the development of molecules used as inhibitors of viral replication in this genus.

Seroprevalencia de anticuerpos a virus del sarampión, rubeola, parotiditis, hepatitis B y los tres serotipos de poliovirus, en niños de Quindío, Colombia / Seroprevalence of antibodies to measles, rubella, mumps, hepatitis B viruses and all three poliovirus serotypes among children in Quindío, Colombia

Objetivo Determinar la seroprevalencia de anticuerpos a virus de sarampión, rubeola, parotiditis, hepatitis B y los tres serotipos de poliovirus en población infantil del Departamento del Quindío, Colombia. Métodos Se colectaron muestras de sangre de 170 niños en edades comprendidas entre los cinco y nueve años de nueve departamentos del Quindío. Se determinó la presencia de anticuerpos tipo IgG para sarampión, rubeola y parotiditis mediante un ELISA indirecto comercial. La inmunidad contra la poliomielitis se determinó por la presencia de anticuerpos neutralizantes a poliovirus según los métodos recomendados por OMS. Resultados De los 170 niños estudiados, 169 (99,41 %), 170 (100 %), and 167 (98,2 %) fueron seropositivos a poliovirus 1, poliovirus 2, y poliovirus 3, respectivamente. El título promedio geométrico de anticuerpos fue 178 para poliovirus tipo 1, 120 para el tipo 2 y 56 para el tipo 3. De los 170 niños, el 96,47 % estuvo protegido contra parotiditis y rubeola y el 86,47 % contra sarampión. Se demostró respuesta serológica positiva contra el virus de la hepatitis B solamente en el 62,35 % de las muestras. Conclusiones El programa de inmunización en el Quindío permitió la seroprotección contra los tres serotipos de la polio, rubeola y parotiditis. Sin embargo, la población infantil no está completamente protegida contra la infección con sarampión y virus de la hepatitis B.(AU)

Objective The main goal of this research was to assess the seroprevalence of antibodies against measles, rubella, mumps, hepatitis B and all three poliovirus serotypes among children in the Quindío Department, Colombia. Methods Blood samples were obtained from 170 healthy children aged 5-9 years from nine municipalities in Quindío. The presence of serum IgG antibodies against measles, rubella, mumps and Hepatitis B were determined using commercial indirect ELISA kits. Immunity to poliomyelitis was assessed through the presence of neutralizing antibodies following the method recommended by the World Health Organization. Results Among the 170 children enrolled, 169 (99.41%), 170 (100 %), and 167 (98.2 %) were seropositive to poliovirus 1, poliovirus 2, and poliovirus 3, respectively. The average reciprocal antibody titers were 178 for poliovirus type 1, 120 for type 2 and 56 for type 3. Of the 170 children, 96.47 % were protected against mumps and rubella, and 86.47 % against measles. Only 106 (62.35 %) of the studied subjects were proved to be seropositive to hepatitis B. Conclusion The immunization program in Quindío has provided seroprotection against all three poliomyelitis serotypes, rubella and mumps. However, the child population is not fully protected against measles and hepatitis B virus infections.(AU)

[Seroprevalence of antibodies to measles, rubella, mumps, hepatitis B viruses and all three poliovirus serotypes among children in Quindío, Colombia]. / Seroprevalencia de anticuerpos a virus del sarampión, rubeola, parotiditis, hepatitis B y los tres serotipos de poliovirus, en niños de Quindío, Colombia.

Objective The main goal of this research was to assess the seroprevalence of antibodies against measles, rubella, mumps, hepatitis B and all three poliovirus serotypes among children in the Quindío Department, Colombia. Methods Blood samples were obtained from 170 healthy children aged 5-9 years from nine municipalities in Quindío. The presence of serum IgG antibodies against measles, rubella, mumps and Hepatitis B were determined using commercial indirect ELISA kits. Immunity to poliomyelitis was assessed through the presence of neutralizing antibodies following the method recommended by the World Health Organization. Results Among the 170 children enrolled, 169 (99.41%), 170 (100 %), and 167 (98.2 %) were seropositive to poliovirus 1, poliovirus 2, and poliovirus 3, respectively. The average reciprocal antibody titers were 178 for poliovirus type 1, 120 for type 2 and 56 for type 3. Of the 170 children, 96.47 % were protected against mumps and rubella, and 86.47 % against measles. Only 106 (62.35 %) of the studied subjects were proved to be seropositive to hepatitis B. Conclusion The immunization program in Quindío has provided seroprotection against all three poliomyelitis serotypes, rubella and mumps. However, the child population is not fully protected against measles and hepatitis B virus infections.

[Absence of poliovirus circulation in Colombian departments with vaccination coverage below 80%]. / Ausencia de circulación de poliovirus en departamentos colombianos con coberturas vacunales inferiores a 80%

This study aims to explore a possible silent circulation of wild and vaccine-derived polioviruses in departments of Colombia with polio vaccination coverage of below 80%. The study collected 52 samples of wastewater concentrated as a result of precipitation with polyethylene glycol and sodium chloride. The viral detection was carried out through isolation and the identification through neutralization of the cytopathic effect, as well as through a conventional polymerase chain reaction following reverse transcription. The isolated polioviruses were characterized by the VP1 gene sequence. In two of the 52 samples, there was a presence of the Sabin type 2 poliovirus with more than 99% sequence similarity with the Sabin type 2 strain polio. Circulation of the nonpolio enterovirus was detected in 17.3% of the samples. The serotypes identified corresponded to coxsackievirus B1, echovirus 30, and echovirus 11. No evidence of the spread of either vaccine-derived poliovirus or wild poliovirus was detected in the departments of Colombia with polio coverage lower than 80%.

Serum levels of dehydroepiandrosterone sulfate (DHEAS) in ocular toxoplasmosis.

There are no previous study about ocular toxoplasmosis and serum levels of dehydroepiandrosterone sulphated hormone (DHEAS). We use the chemoluminiscence automatized Immulite assay to determine the levels of DHEAS. Four groups were studied: (1) Individuals with chronic asymptomatic infection with a positive test for IgG anti-Toxoplasma and without ocular lesions (n = 16); (2) Chronic asymptomatic patients with retinal scars of retinochoroiditis by Toxoplasma (n = 19); (3) Acute symptomatic patients with active retinochoroiditis by Toxoplasma (n = 26); (4) Individuals with negative assays for IgG anti-Toxoplasma (n = 21). Comparison of DHEAS levels between groups were adjusted by age and sex and non-parametric Kruskall Wallis statistical tests were applied. No significant differences in serum levels of DHEAS were found between groups when age and sex were controlled. DHEAS levels were not significantly different in active ocular toxoplasmosis related to non active or non infected persons.

Prevalencia de enterovirus en recién nacidos y lactantes que consultaron a un centro de atención de primer nivel, Armenia, Colombia, 2009 / Prevalence of enterovirus infection in infants in Armenia, Colombia, 2009

Introducción. Los enterovirus están distribuidos por todo el mundo; sin embargo, existe escasa información sobre su circulación en Colombia. Objetivo. Estimar la prevalencia de circulación de enterovirus en niños menores de un año que asistieron a un centro de atención de primer nivel en Armenia, Colombia, en el 2009, e identificar los principales serotipos de enterovirus circulantes. Materiales y métodos. Se tomaron 320 muestras de heces de niños menores de un año de edad. La presencia de enterovirus se determinó mediante transcripción inversa y la reacción en cadena de la polimerasa anidada (RT-N-PCR), empleando iniciadores genéricos de enterovirus. Las muestras que resultaron positivas en la RT-N-PCR, se inocularon en cultivos celulares apropiados para enterovirus. Los aislamientos obtenidos se identificaron por neutralización con la mezcla de sueros de Lim-Benyesh-Melnick. Resultados. Se detectaron enterovirus en 43 de las 320 (13,3 %) muestras de heces mediante RTN-PCR (IC95%: 9,7 a 17,1). Se obtuvo aislamiento viral en 26 de las 43 (60,4 %) muestras de heces positivas por RT-N-PCR. De los 26 aislamientos obtenidos, en 15 se identificó Coxsackie virus B (ocho CVB1, dos CVB2 y cinco CVB5) y 11 echovirus (seis E6 y cinco E30). Conclusiones. La circulación de enterovirus en la población infantil estudiada fue de 13,3 % y los serotipos de enterovirus aislados corresponden con los serotipos de mayor prevalencia global. Los resultados obtenidos indican la factibilidad de emplear la RT-N-PCR como herramienta para vigilar la circulación de enterovirus en muestras de heces.

Introduction. Despite world wide circulation of enteroviruses, little information has accumulated on the circulation of enteroviruses in Colombia. Objective. The prevalence of enterovirus circulation was examined in children under 1 year to identify the most common enterovirus serotypes. Materials and methods. Fecal samples were collected from 320 children under 1 year of age who attended a first-level health center in the city of Armenia, Colombia, in 2009. Enterovirus detection was performed by reverse transcription reaction and nested polymerase chain reaction (RT-N-PCR) using generic enterovirus primers. Samples testing positive in the RT-N-PCR were inoculated into cell cultures susceptible to enterovirus. All isolates were typed by seroneutralization with Lim-Benyesh-Melnick antiserum pools. Results. Overall, enteroviral RNA was detected in 43 of 320 (13.3%; 95% CI: 9.7 to 17.1) fecal samples by RT-N-PCR. Viral isolation was possible in 26 of 43 (60.4%) of the positive samples. Of these, 15 were Coxsackievirus B (eight CVB1, two CVB2, five CVB5) and 11 Echovirus (six E6 and five E30). Conclusions. The enteroviral circulation in a population on newly bornes up to 1 year old was 13.3%;the most frequent enterovirus was the same as those serotypes most commonly isolated in other parts of the world. The use of RT-N-PCR was demonstrably feasible as a tool to monitor the presence of enterovirus in stool samples.

[Prevalence of enterovirus infection in infants in Armenia, Colombia, 2009]. / Prevalencia de enterovirus en recién nacidos y lactantes que consultaron a un centro de atención de primer nivel, Armenia, Colombia, 2009.

INTRODUCTION: Despite world wide circulation of enteroviruses, little information has accumulated on the circulation of enteroviruses in Colombia. OBJECTIVE: The prevalence of enterovirus circulation was examined in children under 1 year to identify the most common enterovirus serotypes. MATERIALS AND METHODS: Fecal samples were collected from 320 children under 1 year of age who attended a first-level health center in the city of Armenia, Colombia, in 2009. Enterovirus detection was performed by reverse transcription reaction and nested polymerase chain reaction (RT-N-PCR) using generic enterovirus primers. Samples testing positive in the RT-N-PCR were inoculated into cell cultures susceptible to enterovirus. All isolates were typed by seroneutralization with Lim-Benyesh-Melnick antiserum pools. RESULTS: Overall, enteroviral RNA was detected in 43 of 320 (13.3%; 95% CI: 9.7 to 17.1) fecal samples by RT-N-PCR. Viral isolation was possible in 26 of 43 (60.4%) of the positive samples. Of these, 15 were Coxsackievirus B (eight CVB1, two CVB2, five CVB5) and 11 Echovirus (six E6 and five E30). CONCLUSIONS: The enteroviral circulation in a population on newly bornes up to 1 year old was 13.3%;the most frequent enterovirus was the same as those serotypes most commonly isolated in other parts of the world. The use of RT-N-PCR was demonstrably feasible as a tool to monitor the presence of enterovirus in stool samples.