[Emergence of CMY-2-type plasmid-mediated AmpC ß-lactamase in Shigella sonnei and Salmonella spp. in Costa Rica, 2003-2015]. / Emergencia de ß-lactamasa AmpC plasmídica del grupo CMY-2 en Shigella sonnei y Salmonella spp. en Costa Rica, 2003-2015.

Plasmid-mediated AmpC are enzymes belonging to the group of ß-lactamases and encoded by bla AmpC genes. Of these enzymes, those known as type CMY-2 are the most frequently reported worldwide. Detection of enterobacteria that produce CMY-2-type plasmid-mediated AmpC is clinically important since the use of ß-lactam antibiotics can result in treatment failure. It is also important from a public health standpoint owing to the capacity for conjugative plasmid transfer to other enterobacteria, both within the community and in nosocomial environments. Thus, bacteria of this kind are considered to have clear epidemic potential. To investigate the circulation of this resistance mechanism among Salmonella and Shigella isolates in Costa Rica, from January 2003 to May 2015 we carried out a retrospective review of the data contained in the laboratory surveillance databases of the National Reference Bacteriology Center (CNRB) of the Costa Rican Nutrition and Health Research Institute (Inciensa). Over this period, 4363 Shigella isolates and 1785 Salmonella isolates were examined. Among them, 15 Shigella sonnei isolates and nine Salmonella isolates (four from human clinical specimens and five of avian origin) displayed a phenotype suspected of carrying plasmid-mediated AmpC. Polymerase chain reaction confirmed that all these isolates belong to type CMY-2. In light of these results, we recommend that the microbiology laboratories in the national network continue to conduct surveillance and confirm any suspicious isolates using phenotypic and molecular methods. This is particularly relevant when dealing with bacterial isolates from extraintestinal infections so as to prevent treatment failure.

Molecular characterization of norovirus and sapovirus detected in animals and humans in Costa Rica: Zoo-anthropozoonotic potential of human norovirus GII.4.

Background: Noroviruses (NoV) and sapoviruses (SaV) are major causes of acute viral gastroenteritis in humans worldwide, as well as gastrointestinal infections in animals. However, it has not been determined whether these viruses are zoonotic pathogens. Aim: In this study, we investigated the presence of NoV and SaV in stool samples from dogs, pigs, cows, and humans to determine some aspects of the molecular epidemiology and the genetic relationship of several strains present in these species. Methods: Polymerase chain reaction and sequencing of NoV and SaV strains present in stool samples from humans and dogs with diarrhea, pigs, and cattle with and without diarrhea were carried out during fragmented periods from 2002 to 2012. Results: Of all samples analyzed, 11.6% (123/1,061) of the samples were positive for NoV and 0.88% (9/1,023) were positive for SaV. The phylogenetic analysis confirmed 16 human strains of NoV (HuNoV) belonging to HuNoV G?/GII.P2 (1), GII.4/GII.P4 (5), G?/GII.P4 (9), and GII.6/GII.P6 (1) and allowed us to verify and assign three strains of human SaV to genotypes GI.2 (1) and GII.5 (2). In dogs, eight strains of NoV [HuNoV G?/GII.P4 (4) and canine G?/GVI.P1 (4)] and two strains of canine SaV were determined. In pigs, six strains were assigned to HuNoV G?/GII.P4 and four strains to porcine SaV were assigned to genogroup GIII (2), GVIII (1), and GXI (1). In bovines, five strains were characterized as HuNoV G?/GII.P4. Conclusions: This study showed that NoV and SaV prototype strains have been present in humans and dogs in Costa Rica. Additionally, it revealed that the zoonotic potential of SaV is very limited, while the zoonotic implications for HuNoV GII.4 are stronger due to the simultaneous circulation of strains related to HuNoV GII.4 in four species, which suggests a zoo-anthropozoonosis.

SALMATcor: microagglutination for Salmonella flagella serotyping.

Salmonella is a complex bacterial group with more than 2400 serovars widely distributed in nature; they are considered zoonotic because they can infect a variety of animals and be transmitted to humans. Usually, they cause alimentary acquired diseases such as gastroenteritis, typhoid fever, and others that can lead to severe complications and death. Serotyping is useful to differentiate among Salmonella, because it shows an important correlation with their clinical and epidemiological patterns; consequently, it is of high value for public health, animal health, agriculture, and industry. To characterize all known Kauffmann-White Salmonella serovars, over 250 antisera are required. Due to this and to high prices antisera, many laboratories worldwide have limitations in establishing Salmonella surveillance. Therefore, we developed and validated a Salmonella flagella microagglutination test (SALMATcor) that significantly reduces laboratory requirements of antisera. SALMATcor is based on scaling down, by fivefold, the antigen:antiserum volumes actually required for the reference method: flagella standard tube agglutination technique (STAT). Antigen preparation, temperatures, and incubation periods remained as established for STAT. The SALMATcor was validated according to ISO/DIS 16140:1999 protocol, which included 1187 comparisons of flagella determinations conducted by SALMATcor and STAT, on 141 Salmonella isolates of 12 common serotypes and the use of antiserum recommended for STAT. SALMATcor concordance was excellent (Cohen's kappa index 0.9982), obtaining relative accuracy >99.9% and relative specificity >99.9%. Additionally, SALMATcor has been used by CNRB-INCIENSA since 2004 to respond to all 40 Salmonella proficiency testing strains, provided by World Health Organization-Global Salmonella Surveillance Network, obtaining 100% concordance on serovar identification. On the basis of the results achieved with SALMATcor and considering that it also significantly reduces antiserum expenses, hand labor, glassware, and bench top and water bath space requirements (microtiter plates and micropipette tips are the only additional supplies), we envision that SALMATcor will contribute to establish a sustainable Salmonella serovar surveillance worldwide.

Differential expression of TP53 associated genes in Fanconi anemia cells after mitomycin C and hydroxyurea treatment.

Fanconi anemia (FA) is a rare, heritable chromosomal instability disease characterized by several congenital defects and cancer predisposition. Functional interactions between specific FA proteins and DNA damage response and repair activities have been reported, but the interplay between these mechanisms for maintaining genomic stability are not well understood. Many DNA damage response proteins are transcriptionally regulated by the tumor suppressor protein p53 (TP53), suggesting an important regulatory role for the DNA damage and stress response pathway. To better understand the association between FA and the DNA damage stress response we analyzed the levels of chromosomal damage and damage mediated gene transcription responses in lymphoblastoid cells derived from normal individuals and patients carrying the most common FA complementation group (FA-A). Chromosomal aberrations were first measured after exposure to mitomicyn C (MMC) or hydroxyurea (HU). Aliquots of the same cell were than assayed for the transcriptional response of 21 DNA damage and stress response genes using quantitative real-time PCR. The FA-A lymphoblastoid cells showed significant increases in the frequency of chromosome aberrations relative to non-FA-A lymphoblastoid lines after MMC treatment. The MMC induced damage was correlated with a general increase in expression of TP53-modulated DNA damage stress response genes involved in processes such as DNA repair, cell cycle progression, and apoptosis. Following HU treatment FA cells showed a decreased induction of CAs with much less transcriptional differences between targeted genes. Overall, the differences between the normal and FA-A cells after genotoxic treatments imply an increased activation and reliance of FA cells on the down-stream activities of TP53 for prevention of cell killing and chromosome damage from interstrand crosslinks but not for general replication arrest and double strand breaks. Furthermore, these results imply a regulatory connection between the FA pathway and activation of TP53 for responding to DNA damage. Alterations in the regulation of the DNA damage response may be related to the complex phenotypes seen in FA patients.

[The Moral Deliberation: The Clinical Ethics Method. Presentation of a Paediatric Case]. / La deliberación moral: el método de la ética clínica. A propósito de un caso de paciente pediátrico.

Decision-making is one of the most difficult tasks of medical judgment, especially when cases involve paediatric patients with different cultural characteristics. It is the obligation of clinical ethics, taking the interdisciplinary approach as a tool to comprehensively analyse the clinical, social, cultural and legal aspects, among other topics, when choosing the treatment options that will be more beneficial for the patient. A clinical case, should enable this process of analysis and teamwork to be understood in practical way in order to address difficult medical problems.

Assessment of physical education time and after-school outdoor time in elementary and middle school students in south Mexico City: the dilemma between physical fitness and the adverse health effects of outdoor pollutant exposure.

Strategies to promote lifelong physical activity among children are needed to stem the adverse health consequences of inactivity. However, the health effects in growing children of long-term exposure to a polluted atmosphere are of deep concern. The atmosphere of south Mexico City (SMC) is characterized by a complex mixture of air pollutants, including ozone, particulate matter, and aldehydes. Radiological evidence suggests that small-airway disease could be present in clinically healthy, tobacco unexposed SMC children. The aim of this study was to assess, by means of a self-reported questionnaire, the physical education class times, daily outdoor after-school exposure time, and tobacco exposure in students attending public elementary and middle schools in SMC. Additionally, the time each student spent viewing television was assessed, and the authors measured each student's weight and height to determine body mass index (BMI, weight in kg divided by height in m2). The survey included 1,159 students in grades 7-9. The authors identified 2 critical periods of outdoor exposure in SMC children that coincided with significant concentrations of both ozone and particulate matter with diameters less than 10 micrometers (PM10): during school time after 11:00 A.M. and in the after-school outdoor activity period, usually extending from 1:00 P.M. to 6:00 P.M. Thirty-two percent of elementary and 61% of middle school students have physical education classes after 11:00 A.M. Students in SMC spend an average of 19.6 hr/wk outdoors in the after-school period, during which time they are engaged in light to moderate physical activities. Half of the students are exposed to tobacco smoke at home, and 7% of middle school students smoke. On the basis of BMI, 60% of students were classified as undernourished, overweight, or obese. No correlations were found between BMI and time spent viewing TV, time outdoors (on weekdays and weekends), or exposure to environmental tobacco smoke. Children and adolescents in SMC are participating in physical activities that enhance multiple components of health-related fitness. However, their activities occur outdoors, where they are exposed to high concentrations of air pollutants throughout the year. The authors believe that SMC children and adolescents must be educated, through both the school and health systems, regarding ways to obtain the necessary exercise while protecting themselves from the high concentrations of pollutants. Individuals should instruct and encourage young people to be involved in lifetime fitness activities and to eat balanced diets, if the goal is to control health-care costs, reduce disease incidence, and improve the overall quality of life of the Mexico City population.

La deliberación moral: el método de la ética clínica. A propósito de un caso de paciente pediátrico / The Moral Deliberation: The Clinical Ethics Method. Presentation of a Paediatric Case

La toma de decisiones es una de las tareas más complejas del quehacer médico, y más cuando los casos afectan a pacientes pediátricos y con características socioculturales especiales. Es deber de la ética clínica, teniendo la interdisciplinaridad como herramienta, analizar de manera integral los aspectos clínicos, sociales, culturales y legales, entre otros, que se debe tener en cuenta a la hora de escoger la mejor opción terapéutica que beneficie al paciente. Un caso clínico permitirá entender de manera práctica este proceso de análisis y trabajo en equipo, para abordar problemas médicos difíciles.

Decision-making is one of the most difficult tasks of medical judgment, especially when cases involve paediatric patients with different cultural characteristics. It is the obligation of clinical ethics, taking the interdisciplinary approach as a tool to comprehensively analyse the clinical, social, cultural and legal aspects, among other topics, when choosing the treatment options that will be more beneficial for the patient. A clinical case, should enable this process of analysis and teamwork to be understood in practical way in order to address difficult medical problems.

Emergencia de β-lactamasa AmpC plasmídica del grupo CMY-2 en Shigella sonnei y Salmonella spp. en Costa Rica, 2003-2015 / Emergence of CMY-2-type plasmid-mediated AmpC β-lactamase in Shigella sonnei and Salmonella spp. in Costa Rica, 2003–2015

Las AmpC plasmídicas son enzimas del grupo de las β-lactamasas, codificadas por genes blaAmpC. Entre ellas, las del tipo CMY-2 son las que se reportan con mayor frecuencia a nivel mundial. La detección de enterobacterias productoras de AmpC plasmídicas CMY-2 es de importancia clínica, ya que pueden conducir a fracasos terapéuticos al emplear antibióticos b-lactámicos. Además, tienen importancia para la salud pública por su capacidad de transferirse por conjugación a otras enterobacterias, tanto en la comunidad como en ambiente nosocomial, por lo que se considera que tienen un claro potencial epidémico. Con el fin de conocer la circulación de este mecanismo de resistencia entre aislamientos de Salmonella y Shigella en Costa Rica, se realizó un análisis retrospectivo de la información contenida en las bases de datos de vigilancia de laboratorio del Centro Nacional de Referencia de Bacteriología (CNRB) del Instituto Costarricense de Investigación y Enseñanza en Nutrición y Salud (Inciensa), entre enero de 2003 y mayo de 2015. En dicho período se analizaron 4 363 aislamientos de Shigella y 1 785 aislamientos de Salmonella. Entre ellos se detectaron 15 aislamientos de Shigella sonnei y nueve de Salmonella (cuatro de origen clínico humano y cinco de origen aviar) con fenotipo sospechoso de portar AmpC plasmídica, todos los cuales se confirmaron pertenecientes al tipo CMY-2 mediante reacción en cadena de la polimerasa. Considerando estos resultados, se recomienda a los laboratorios de microbiología de la Red Nacional mantener la vigilancia y realizar la confirmación correspondiente de cualquier aislamiento sospechoso por métodos fenotípicos y moleculares. Lo anterior es especialmente importante en bacterias aisladas de infecciones extraintestinales, para evitar fallas en el tratamiento.

Plasmid-mediated AmpC are enzymes belonging to the group of β-lactamases and encoded by blaAmpC genes. Of these enzymes, those known as type CMY-2 are the most frequently reported worldwide. Detection of enterobacteria that produce CMY-2-type plasmid-mediated AmpC is clinically important since the use of β-lactam antibiotics can result in treatment failure. It is also important from a public health standpoint owing to the capacity for conjugative plasmid transfer to other enterobacteria, both within the community and in nosocomial environments. Thus, bacteria of this kind are considered to have clear epidemic potential. To investigate the circulation of this resistance mechanism among Salmonella and Shigella isolates in Costa Rica, from January 2003 to May 2015 we carried out a retrospective review of the data contained in the laboratory surveillance databases of the National Reference Bacteriology Center (CNRB) of the Costa Rican Nutrition and Health Research Institute (Inciensa). Over this period, 4363 Shigella isolates and 1785 Salmonella isolates were examined. Among them, 15 Shigella sonnei isolates and nine Salmonella isolates (four from human clinical specimens and five of avian origin) displayed a phenotype suspected of carrying plasmid-mediated AmpC. Polymerase chain reaction confirmed that all these isolates belong to type CMY-2. In light of these results, we recommend that the microbiology laboratories in the national network continue to conduct surveillance and confirm any suspicious isolates using phenotypic and molecular methods. This is particularly relevant when dealing with bacterial isolates from extraintestinal infections so as to prevent treatment failure.

Air pollution and brain damage.

Exposure to complex mixtures of air pollutants produces inflammation in the upper and lower respiratory tract. Because the nasal cavity is a common portal of entry, respiratory and olfactory epithelia are vulnerable targets for toxicological damage. This study has evaluated, by light and electron microscopy and immunohistochemical expression of nuclear factor-kappa beta (NF-kappaB) and inducible nitric oxide synthase (iNOS), the olfactory and respiratory nasal mucosae, olfactory bulb, and cortical and subcortical structures from 32 healthy mongrel canine residents in Southwest Metropolitan Mexico City (SWMMC), a highly polluted urban region. Findings were compared to those in 8 dogs from Tlaxcala, a less polluted, control city. In SWMMC dogs, expression of nuclear neuronal NF-kappaB and iNOS in cortical endothelial cells occurred at ages 2 and 4 weeks; subsequent damage included alterations of the blood-brain barrier (BBB), degenerating cortical neurons, apoptotic glial white matter cells, deposition of apolipoprotein E (apoE)-positive lipid droplets in smooth muscle cells and pericytes, nonneuritic plaques, and neurofibrillary tangles. Persistent pulmonary inflammation and deteriorating olfactory and respiratory barriers may play a role in the neuropathology observed in the brains of these highly exposed canines. Neurodegenerative disorders such as Alzheimer's may begin early in life with air pollutants playing a crucial role.

Brotes de diarrea e intoxicaciones transmitidas por alimentos en Costa Rica, 2005

Justificación y objetivo: En la actualidad, las enfermedades de transmisión alimentaria, incluyendo las diarreas e intoxicaciones, constituyen uno de los problemas de salud pública de mayor importancia a nivel mundial, ya que ocasionan alta morbilidad y mortalidad, generan grandes costos a los servicios de salud, pérdidas económicas, demandas y pérdida de confianza de los consumidores. El objetivo del trabajo es analizar la información disponible en el Centro Nacional de Referencia en Bacteriología del INCIENSA (CNRB), de los brotes de diarrea e intoxicaciones alimentarias ocurridos en 2005, en los que se refirieron muestras clínicas o de alimentos, para identificar los agentes y vehículos de infección asociados. Materiales y métodos: Se realizó el análisis descriptivo de la información epidemiológica y de laboratorio disponible en el CNRB en relación con los brotes de diarrea e intoxicaciones alimentarias ocurridos en 2005. Resultados: Durante el período el CNRB documentó 23 brotes de diarrea e intoxicaciones alimentarias, para un total aproximado de 819 afectados, en su mayoría procedentes de la gran área metropolitana. Trece de los brotes fueron intrafamiliares (diez de ellos debidos a especies y serotipos de Shigella); sin embargo, el mayor número de enfermos se presentó en los brotes comunitarios y los que se produjeron en poblaciones cautivas, asociados a rotavirus, Escherichia coli enterotoxigénica y Clostridium perfringens productor de toxina A, con 518, 138 y 54 enfermos, respectivamente. Conclusión: Estos hallazgos evidencian deficiencias en la cadena de transporte, conservación y manipulación de los alimentos, así como en la higiene personal, y pueden ser de utilidad para la implementación de intervenciones inmediatas.

Brotes de diarrea e intoxicaciones transmitidas por alimentos en Costa Rica, 2005 / Outbreaks of diarrhea and transmitted by food poisoning in Costa Rica, 2005

Justificación y objetivos: En la actualidad, las enfermedades de transmisión alimentaria, incluyendo las diarreas e intoxicaciones, constituyen uno de los problemas de salud pública de mayor importancia a nivel mundial, ya que ocasionan alta morbilidad y mortalidad, generan grandes costos a los servicios de salud, pérdidas económicas, demandas y pérdida de confianza de los consumidores. El objetivo del trabajo es analizar la información disponible en el Centro nacional de referencia en bacteriología del INCIENSA, CNRB, de los brotes de diarrea e intoxicaciones alimentarias ocurridos en 2005, en los que se refirieron muestras clínicas o de alimentos, para identificar los agentes y vehículos de infección asociados. Materiales y métodos: Se realizó el análisis descriptivo de la información epidemiológica y de laboratorio disponible en el CNRB en relación con los brotes de diarrea e intoxicaciones alimentarias ocurridos en 2005. Resultados: Durante el período el CNRB documentó 23 brotes de diarrea e intoxicaciones alimentarias, para un total aproximado de 819 afectados, en su mayoría procedentes de la gran área metropolitana. Trece de los brotes fueron intrafamiliares, diez de ellos debidos a especies y serotipos de Shigella; sin embargo, el mayor número de enfermos se presentó en los brotes comunitarios y los que se produjeron en poblaciones cautivas, asociados a rotavirus, Escherichia coli enterotoxigénica y Clostridium productor de toxina A, con 518, 138 y 54 enfermos, respectivamente. Conclusión: Estos hallazgos evidencian deficiencias en la cadena de transporte, conservación y manipulación de los alimentos, así como en la higiene personal, y pueden ser de utilidad para la implementación de intervenciones inmediatas.