Revisión rápida: monitoreo de la presencia e infectividad del virus SARS-CoV-2 y otros coronavirus en aguas residuales / Quick review: monitoring the presence and infectivity of SARS-CoV-2 and other coronaviruses in wastewater

Resumen: Objetivo: Describir la evidencia sobre la presencia e infectividad de SARS-CoV-2 y otros coronavirus en aguas residuales y su potencial uso como herramienta de vigilancia epidemiológica. Material y métodos: Búsqueda de publicaciones en PubMed y medRxiv desde enero 2003 hasta el 8 de junio de 2020 de acuerdo con la guía de revisiones rápidas de Cochrane. Resultados: Se incluyeron 29 publicaciones. El ARN de SARS-CoV-2 no infectivo se encontró en agua residual hospitalaria, agua residual cruda, tratada y lodos de plantas de tratamiento. Los niveles cuantitativos de ARN viral en agua residual presentan relación con el número de casos de Covid-19. SARS-CoV-1 y otros coronavirus permanecieron infectivos en agua residual cruda hasta por dos días. Conclusiones: Hasta esta revisión no existe evidencia sobre la presencia de virus infectivos de SARS-CoV-2 en agua residual cruda o tratada. La cuantificación de ARN de SARS-CoV-2 en agua residual es útil para la vigilancia epidemiológica.

Abstract: Objective: To describe the current evidence on the presence and infectivity of SARS-CoV-2 and other coronaviruses in wastewater; and its potential use as an epidemiological surveillance tool. Materials and methods: A search was performed in PubMed and medRxiv databases from January 2003 to June 8, 2020 according to the Cochrane Rapid Review Guide. Results: Twenty-nine publications were included. Non-infective RNA of SARS-CoV-2 has been detected in hospital sewage; raw and treated wastewater, and primary sludges from sewage treatment plants. Quantitative levels of viral RNA in wastewater are related with the number of Covid-19 cases. SARS-CoV-1 and other coronaviruses remained infective in wastewater up to two days. Conclusions: Currently, there is no evidence of the presence of infective SARS-CoV-2 in wastewater and its inactivation through treatment/disinfection has been proven. Quantification of SARS-CoV-2 RNA in wastewater can be a useful epidemiological surveillance tool.

Determinación de la adquisición del Streptococcus grupo mutans en un grupo de niños uruguayos de hasta 36 meses de edad / Determinação da aquisição do grupo Streptococcus mutans em um grupo de crianças uruguaias até 36 meses de idade / Determination of the acquisition of Mutans Streptococci in a group of Uruguayan children up to 36 months of age

Introducción: La boca del recién nacido se contamina inmediatamente con microorganismos maternos. Caufield determinó la colonización con SGM para niños americanos a los 26 meses de edad. Estudios latinoamericanos la ubican entre los 14,9-18 meses. Objetivos: Identificar el momento de adquisición y colonización del SGM en una población de niños uruguayos y relacionarlo con factores del niño y maternos. Establecer el tiempo necesario para la recolección de la muestra y estudio de su pérdida. Método: Estudio observacional, longitudinal prospectivo, de 83 pares madre-hijo de un policlínico de Montevideo. De 83 pares examinados, 20 completaron el estudio. Se incluyeron niños de 0-9 meses, con/sin dientes y primera toma salival negativa para SGM. Resultados: Edad promedio de adquisición del SGM 16,4 meses (±4,13) y colonización 18,6 meses (±3,80) de edad. La pérdida de la muestra fue 71,42%. Conclusiones: La colonización resultó similar a la encontrada por Florio (Brasil), observándose diferencias significativas con Caufield (EEUU).

Introduction: The newborn's mouth is immediately contaminated with maternal microorganisms during birth. Caufield determined that the average age of colonization with Streptococcus Mutans (SM) for American children was 26 months old. Latin American studies indicate that it occurs at an age between 14.9 and 18 months old. Objectives: To identify the time of Sm acquisition and colonization in a population of Uruguayan children and to relate it with various child and mother factors. To establish the time needed to collect the sample and its loss. Methods: Observational, longitudinal prospective study, of 83 mother-child pairs from a medical center in Montevideo. From the 83 pairs examined, 20 completed the study. Children between 0-9 months old, with/without teeth, whose first salivary sample was negative for Sm, were included. Results: The mean age of Sm acquisition was 16.4 months (± 4.13), and colonization occurred at 18.6 months (± 3.80) of age. The sample loss was 71.42%. Conclusions: The colonization found was similar to that found by Florio (Brazil) but showed significant differences with Caufield's results (USA).

Introdução: A boca do recém-nascido é imediatamente contaminada por microrganismos maternos. Caufield determinou a colonização com SGM para crianças americanas aos 26 meses de idade. Estudos latino-americanos o situam entre 14,9-18 meses. Objetivos: Identificar o momento de aquisição e colonização do SGM em uma população de crianças uruguaias e relacioná-lo com fatores da criança e da mãe. Estabeleça o tempo necessário para coletar a amostra e estudar sua perda. Método: Estudo observacional, longitudinal prospectivo, de 83 pares mãe-filho da uma policlínica de Montevidéu. Dos 83 pares examinados, 20 completaram o estudo. Foram incluídas crianças de 0-9 meses com / sem dentes e primeira amostra salivar negativa para SGM. Resultados: Idade média de aquisição do SGM 16,4 meses (± 4,13) e colonização 18,6 meses (± 3,80) de idade. A perda estabelecida da amostra foi 71,42%. Conclusões: A colonização foi semelhante aos de Florio (Brasil), observando diferenças significativas com Caufield (EUA).

Determinación de la adquisición del Streptococcus grupo mutans en un grupo de niños uruguayos de hasta 36 meses de edad Estudio piloto / Determinação da aquisição do grupo Streptococcus mutans em um grupo de crianças uruguaias até 36 meses de idade. Estudo piloto / Determination of the acquisition of Mutans Streptococci in a group of Uruguayan children up to 36 months of age. Pilot study

Resumen: Introducción: La boca del recién nacido se contamina inmediatamente con microorganismos maternos. Caufield determinó la colonización con SGM para niños americanos a los 26 meses de edad. Estudios latinoamericanos la ubican entre los 14,9-18 meses. Objetivos: -Identificar el momento de adquisición y colonización del SGM en una población de niños uruguayos y relacionarlo con factores del niño y maternos. Establecer el tiempo necesario para la recolección de la muestra y estudio de su pérdida. Método: Estudio observacional, longitudinal prospectivo, de 83 pares madre-hijo de un policlínico de Montevideo. De 83 pares examinados, 20 completaron el estudio. Se incluyeron niños de 0-9 meses, con/sin dientes y primera toma salival negativa para SGM. Resultados: Edad promedio de adquisición del SGM 16,4 meses (±4,13) y colonización 18,6 meses (±3,80) de edad. La pérdida de la muestra fue 71,42%. Conclusiones: La colonización resultó similar a la encontrada por Florio (Brasil), observándose diferencias significativas con Caufield (EEUU).

Resumo: Introdução: A boca do recém-nascido é imediatamente contaminada por microrganismos maternos. Caufield determinou a colonização com SGM para crianças americanas aos 26 meses de idade. Estudos latino-americanos o situam entre 14,9-18 meses. Objetivos: -Identificar o momento de aquisição e colonização do SGM em uma população de crianças uruguaias e relacioná-lo com fatores da criança e da mãe. Estabeleça o tempo necessário para coletar a amostra e estudar sua perda. Método: Estudo observacional, longitudinal prospectivo, de 83 pares mãe-filho da uma policlínica de Montevidéu. Dos 83 pares examinados, 20 completaram o estudo. Foram incluídas crianças de 0-9 meses com / sem dentes e primeira amostra salivar negativa para SGM. Resultados: Idade média de aquisição do SGM 16,4 meses (± 4,13) e colonização 18,6 meses (± 3,80) de idade. A perda estabelecida da amostra foi 71,42%. Conclusões: A colonização foi semelhante aos de Florio (Brasil), observando diferenças significativas com Caufield (EUA)

Abstract: Introduction: The newborn's mouth is immediately contaminated with maternal microorganisms at birth. Caufield determined that the average age of colonization with Mutants streptococci (MS) for American children was 26 months old. Latin American studies indicate that it occurs at an age between 14.9 and 18 months old. Objectives: To identify the time of MS acquisition and colonization in a population of Uruguayan children and to relate it with various child and maternal factors. To establish the time needed to collect the sample and its loss. Methods: Observational, longitudinal prospective study, of 83 mother-child pairs from a medical center in Montevideo. From the 83 pairs examined, 20 completed the study. Children between 0-9 months old, with/without teeth, whose first saliva sample was negative for MS, were included. Results: The mean age of MS acquisition was 16.4 months (± 4.13), and colonization occurred at 18.6 months (± 3.80) of age. The sample loss was 71.42%. Conclusions: The colonization found was similar to that found by Florio (Brazil) but showed significant differences with Caufield's results (USA).

The association of chronic hepatitis B infectivity with fetomaternal outcome: A retrospective cohurt study in a tertiary hospital / Philippine Journal of Obstetrics and Gynecology

Background@#Hepatitis B infection on pregnancy has been linked to preterm labor, risk of prematurity, low birth weight, and the occurrence of gestational diabetes mellitus.@*Objective@#To determine the association between Chronic Hepatitis B infectivity and fetomaternal outcome such as preterm birth, low birth weight, gestational diabetes and preeclampsia among pregnant patients admitted in a Tertiary Hospital.@* Methodology@#A retrospective cohort study was done among pregnant women diagnosed with chronic hepatitis B infection admitted in a tertiary hospital from January 1, 2014 to December 31, 2018. The association of Hepatitis B infectivity and fetomaternal outcomes namely preterm birth, gestational diabetes, preeclampsia and low birth weight was determined.@*Results@#Chronic Hepatitis B infection had 1.43% prevalence among the study group. 149 patients were able to able to fulfill the inclusion criteria. Pregnant women with high infectivity Hepatitis B infection tend to be younger, have lower BMI, have lesser gravidity and parity than patients who are nonreactive to Hepatitis B e-antigen. AST and ALT were also higher among those with high infectivity Hepatitis B. However, there was no significant difference among the two groups in terms of elevated ALT. There was no significant association between Hepatitis B infectivity and fetomaternal outcomes such as preeclampsia, gestational diabetes mellitus, preterm birth and low birth weight. There is no increased risk for patients with high infectivity for preeclampsia, gestational diabetes mellitus, and low birth weight. There appears to be an excess risk in the likelihood of preterm birth/labor among those women who have a high infectivity Hepatitis B infection during pregnancy.@*Conclusion@#The prevalence of chronic hepatitis B infection among Filipino pregnant women admitted in a tertiary hospital was 1.43% from 2014 to 2018. There was no association between chronic hepatitis B infectivity and preeclampsia, Gestational diabetes mellitus. There seems to be an increased risk for HBeAg positive patients for preterm birth preterm labor, and occurrence of low birth weight, but was not statistically significant in the study population.

Infectivity of Simulium damnosum s.l. and therapeutic coverage of ivermectin distribution 10 years post treatment around Owena Dam, Ondo state, Nigeria

ABSTRACT Background: Studies related to infectivity status of insect vectors are seen as necessities in understanding the epidemiology of vector-borne diseases and planning effective control measures. This study assessed the infectivity ofSimulium damnosum s.l. around Owena River as well as evaluated therapeutic coverage of Ivermectin distribution in the area. Method: Human landing sampling method was used to collect adult flies on human attractants from 07:00 to 18:00 for two consecutive days a month for three months (July 2016 - September 2016). Parity assessment was conducted to determine the age of fly populations. Parous flies were further dissected to detect the presence or absence ofOnchocerca larvae. Biting rates and transmission potentials were calculated using standard methods. A quantitative survey was carried out to determine the therapeutic coverage and compliance to ivermectin treatment for the control of Onchocerciasis in the study area using standard household coverage questionnaires. Results: A total of 914 adult female flies were collected during the study period. The daily biting rate (DBR) varied from 146 fly per man day (FMD) in July to 162.5 FMD in August. The monthly biting rate (MBR) was lowest in September (2170 bites per man per month) but highest in August (3358.3 bites per man per month). MBD ranged from 13.23 fly per man hour (FMH) in July to 14.77 FMH in August. The results indicated that the majority of the flies collected at the sampling points were nulliparous [685 (74.95%)] while others were parous [229 (25.05%)]. The biting activity of the flies showed a marked decrease in population in August compared to July which later increased in September. Infection rates varied from 2 (0.7%) in July to 7 (2.2%) in August while the infectivity rate during the study ranged from zero (July and September) to 3 (1.0%) in August. Conclusion: Despite the years of treatment of onchocerciasis in Owena community, there were still some infective flies capable of transmitting O. volvolus. This could be due to the low rate of therapeutic coverage as a result of non-compliance in the community for various reasons earlier stated.

Research progress in the application of identification technology for infectious Norovirus / 中华实验和临床病毒学杂志

Norovirus, as one of the main pathogens causing non-bacterial gastroenteritis, can cause serious public health problems and economic losses around the world. In recent years, the outbreaks caused by the virus in China are on the rise. Human Norovirus (HuNoV) can hardly be cultivated in-vitro. The nucleic acid detection method (such as RT-qPCR) has the highest sensitivity and specificity, but it was not established that the correlation between the detected viral genome and viral infectivity, which leads to inaccurate judgment of safety risks. Here, the in-vitro and in-vivo culture models, viral genome integrity and capsid protein integrity were cut into three aspects. The research progress and characteristics of infectious Norovirus identification technology in recent years were reviewed and discussed, and the future development trend of this technology was prospected. The aim is to further improve the accuracy of Norovirus quantitative detection and provide a theoretical basis for its application in the field of food safety testing.

Desafíos hacia la eliminación de la malaria urbana/peri en Guapi (Colombia), 2016 / Challenges towards elimination of urban/peri-urban malaria in Guapi (Colombia), 2016 / Desafios para a eliminação da malária urbana / peri em Guapi (Colombia), 2016

RESUMEN I: Para mantener la reducción de la malaria, se promueven iniciativas que aceleren la eliminación. En años recientes con la reducción sostenida de la malaria, Colombia hacia el 2021 propone su eliminación en áreas urbanas por lo cual se requieren investigaciones para este desafío O: Establecer la situación epidemiológica de la transmisión de malaria urbana/peri en Guapi 2011-2015 y describir los desafíos en capacidad vectorial, receptividad, infectividad y vulnerabilidad. M: Se realizó un estudio descriptivo, se obtuvieron datos epidemiológicos, entomológicos, parasitológicos, de servicios de salud y socio económicos mediante entrevistas y fuentes secundarias. Con la información se realizaron análisis uni y bivariados, se aplicaron formatos de eliminación de malaria propuestos por la Organización Mundial de la Salud y se analizaron brechas. R: Se notificaron 1097 casos, 39,5% se registraron en el área urbana/peri, y a su vez, el 68% de éstos se concentraron en tres barrios. En capacidad vectorial se identificó como vector primario a anopheles albimanus, con susceptibilidad a los insecticidas, múltiples criaderos y estrategias de instalación de mosquiteros con altas coberturas; en infectividad se encontró predominio de infecciones por p, falciparum, oportunidad de consulta en las primeras 48 horas del 48,1% y automedicación; en vulnerabilidad los casos no urbanos representaron 60,5 % del total. C: La malaria se caracterizó por ser de baja intensidad, focalizada y con picos. Hay significativa receptividad, en infectividad hay retrasos de oportunidad de consulta y existe alta vulnerabilidad por población migrante.

ABSTRACT I: To maintain the reduction of malaria, initiatives that accelerate the elimination are promoted. In recent years with the sustained reduction of malaria, Colombia by 2021 proposes its elimination in urban areas, which requires research for this challenge O: Establish the epidemiological situation of transmission of urban / peri malaria in Guapi 2011-2015 and describe the challenges in vector capacity, receptivity, infectivity and vulnerability. M: A descriptive study was conducted, epidemiological, entomological, parasitological, health and socioeconomic services were obtained through interviews and secondary sources. With the information, univariate and bivariate analyzes were carried out, malaria elimination formats proposed by the World Health Organization were applied and gaps were analyzed. A: 1097 cases were notified, 39.5% were registered in the urban / peri area, and in turn, 68% of these were concentrated in three neighborhoods. In vectorial capacity anopheles albimanus was identified as the primary vector with susceptibility to insecticides, multiple hatcheries and strategies for installing mosquito nets with high coverage; In infectivity, predominance of p. falciparum, 48.1% consultation opportunity in the first 48 hours and self-medication; in vulnerability, non-urban cases represented 60.5% of the total. C: Malaria was characterized by being of low intensity, focused and with spikes. There is significant receptivity, in infectiousness there are delays in the opportunity of consultation and there is high vulnerability due to migrant population.

RESUMO I: Para manter a redução da malária, são promovidas iniciativas que aceleram a eliminação. Nos últimos anos, com a redução sustentada da malária, a Colômbia propõe, até 2021, sua eliminação nas áreas urbanas, o que requer pesquisa para esse desafio O: Estabelecer a situação epidemiológica da transmissão da malária urbana / peri-Guapi 2011-2015 e descrever os desafios em capacidade de vetores, receptividade, infecciosidade e vulnerabilidade. M: Estudo descritivo, epidemiológico, entomológico, parasitológico, de saúde e socioeconómico, obtido por meio de entrevistas e fontes secundárias. Com as informações, foram realizadas análises univariadas e bivariadas, os formatos de eliminação de malária propostos pela Organização Mundial da Saúde foram aplicados e as lacunas foram analisadas. R: 1097 casos foram notificados, 39,5% foram registrados na área urbana / peri e, por sua vez, 68% destes foram concentrados em três bairros. Em capacidade vetorial, anopheles albimanus foi identificado como vetor primário, com suscetibilidade a inseticidas, múltiplos incubatórios e estratégias para a instalação de redes mosquiteiras com alta cobertura; Na infectividade, predomínio de p. falciparum, 48,1% de oportunidade de consulta nas primeiras 48 horas e automedicação; em vulnerabilidade, os casos não urbanos representaram 60,5% do total. C: A malária foi caracterizada por ser de baixa intensidade, focada e com picos. Há uma receptividade significativa, na infecciosidade há atrasos na oportunidade de consulta e há alta vulnerabilidade devido à população migrante.

Advances in the nucleic acid detection method integrated with propidium monoazide to determine the viral infectivity / 中华实验和临床病毒学杂志

Currently, a number of analytical method, such as animal infection test, cell culture assay and polymerase chain reaction, are available for virus detection in clinical samples. The nucleic acid detection method has the highest sensitivity and specificity, but it was not established that the correlation between the detected viral genome and viral infectivity. The nucleic acid detection method integrated with propidium monoazide (PMA) can remedy this shortcoming to determine the viral infectivity. This review firstly describes the principle and procedure of the nucleic acid detection method integrated with PMA. It secondly analyzes the advantages and limitations of the nucleic acid detection method integrated with PMA. Finally, it discusses the influence of the viral structure, the inactivation mode and experimental conditions on the nucleic acid detection method integrated with PMA and summarise the progress of the method.

Treatment of femur re-fracture with occult infection by using non-contact locking plate under deep fascia / 中国修复重建外科杂志

Objective: To investigate the effectiveness on the re-fracture of the femur with occult infection by using non-contact locking plate which was placed under the deep fascia.

Tracing the origin of the NS1 A188V substitution responsible for recent enhancement of Zika virus Asian genotype infectivity

A recent study showed that infectivity of Zika virus (ZIKV) Asian genotype was enhanced by an alanine-to-valine amino acid substitution at residue 188 of the NS1 protein, but the precise time and location of origin of this mutation were not formally estimated. Here, we applied a Bayesian coalescent-based framework to estimate the age and location of the ancestral viral strain carrying the A188V substitution. Our results support that the ancestral ZIKV strain carrying the A188V substitution arose in Southeastern Asia at the early 2000s and circulated in that region for some time (5-10 years) before being disseminated to Southern Pacific islands and the Americas.

Avaliação da infectividade parasitária a Lutzomyia longipalpis por xenodiagnóstico em cães tratados para leishmaniose visceral naturalmente adquirida / Evaluation of parasite infectivity for Lutzomyia longipalpis by xenodiagnosis in dogs treated for natural visceral leishmaniasis

O efeito de um protocolo quimioterápico multidrogas contra a leishmaniose visceral (LV) canina, sobre a capacidade de transmissão de Leishmania infantum ao vetor, foi analisado por meio de xenodiagnóstico. Trinta e cinco cães naturalmente infectados foram avaliados antes e durante o tratamento com a combinação de metronidazol, cetoconazol e alopurinol a cada três meses por até um ano. Em cada avaliação, os cães foram individualmente submetidos ao xenodiagnóstico e quantificação da carga parasitária por PCR quantitativa. O tratamento foi eficaz em bloquear a transmissibilidade parasitária do cão para o flebotomíneo (p= 0,011) nos cães avaliados. Houve significante correlação entre recuperação clínica e infectividade: cães com melhora clínica mais evidente apresentaram menores chances de transferir L. infantum ao Lutzomyia longipalpis via xenodiagnóstico (r=0,528, p= 0,002). Esses resultados demonstram que o tratamento canino com o protocolo proposto pode representar uma alternativa ao sacrifício de cães no Brasil como medida de controle da doença, uma vez que as drogas utilizadas não são aplicadas ao tratamento da LV humana em áreas endêmicas.(AU)

The outcome of a multidrug chemotherapeutic protocol against canine visceral leishmaniasis (VL) has been evaluated for its effect on dogs' capacity of transferring Leishmania infantum to sand flies by xenodiagnosis. Thirty-five naturally infected dogs were examined before and during treatment with a combination of metronidazole, ketoconazole, and allopurinol, at every three months up to one year. For each evaluation, treated dogs were individually submitted to xenodiagnosis and quantitative PCR to quantify parasite load in sand flies. The treatment was effective in blocking parasite transmission from host to sand flies (p=0.011) in the assessed dogs. There was a significant correlation between clinical improvement and sand fly infectivity: dogs that achieved better clinical conditions showed a lower chance of L. infantum transference to vector by xenodiagnosis (r=0.528, p=0.002). These results demonstrate that the treatment of dogs with the proposed protocol may represent an alternative to dog culling in Brazil for disease control, since these drugs are not used for treating human VL in endemic areas.(AU)

Phenotypic diversity and selection maintain Leishmania amazonensis infectivity in BALB/c mouse model

Leishmania are protozoan parasites that show remarkable diversity, as revealed by the various clinical forms of leishmaniasis, which can range from mild skin lesions to severe metastatic cutaneous/mucosal lesions. The exact nature and extent of Leishmania phenotypic diversity in establishing infection is not fully understood. In order to try to understand some aspects of this diversity, we subcutaneously infected BALB/c mice with first and second generation subclones of a L. amazonensis strain isolated from a patient (BA125) and examined in vivo lesion growth rate and antimony susceptibility. In vivo fast-, medium- and slow-growing subclones were obtained; moreover, fast-growing subclones could generate slow-growing subclones and inversely, revealing the continuous generation of diversity after passage into mice. No antimony-resistant subclone appeared, probably a rare occurrence. By tagging subclone cells with a L. amazonensis genomic cosmid library, we found that only a very small number of founding cells could produce lesions. Leishmania clones transfected with in vivo selected individual cosmids were also diverse in terms of lesion growth rate, revealing the cosmid-independent intrinsic characteristics of each clone. Our results suggest that only a few of the infecting parasites are able to grow and produce lesions; later, within the cell mixture of each lesion, there coexist several parasite populations with different potentialities to grow lesions during the next infection round. This may reflect a sort of programmed heterogeneity of individual parasites, favoring the survival of some individuals in various environmental conditions.

Infectivity of housefly, Musca domestica (Diptera: Muscidae) to different entomopathogenic fungi

Abstract The housefly Musca domestica is a worldwide insect pest that acts as a vector for many pathogenic diseases in both people and animals. The present study was conducted to evaluate the virulence of different local isolates of Beauveria bassiana, Metarhizium anisopliae and Isaria fumosorosea on M. domestica using two bioassay techniques: (1) adult immersion and (2) a bait method applied to both larvae and adults. The results showed evidence of a broad range of responses by both stages (larvae and adults) to the tested isolates of B. bassiana, M. anisopliae and I. fumosorosea. These responses were concentration-dependent, with mortality percentages ranging from 53.00% to 96.00%. Because it resulted in lower LC50 values and a shorter lethal time, B. bassiana (Bb-01) proved to be the most virulent isolate against both housefly larvae and adults. Sublethal doses of the tested isolates were also assessed to evaluate their effect on M. domestica fecundity and longevity. The fungal infections reduced housefly survival regardless of their sex and also decreased egg production in females.

Stochastic developmental variation, an epigenetic source of phenotypic diversity with far-reaching biological consequences.

This article reviews the production of different phenotypes from the same genotype in the same environment by stochastic cellular events, nonlinear mechanisms during patterning and morphogenesis, and probabilistic self-reinforcing circuitries in the adult life. These aspects of phenotypic variation are summarized under the term‘stochastic developmental variation’ (SDV) in the following. In the past, SDV has been viewed primarily as a nuisance, impairing laboratory experiments, pharmaceutical testing, and true-to-type breeding. This article also emphasizes the positive biological effects of SDV and discusses implications for genotype-to-phenotype mapping, biological individuation, ecology, evolution, and applied biology. There is strong evidence from experiments with genetically identical organisms performed in narrowly standardized laboratory set-ups that SDV is a source of phenotypic variation in its own right aside from genetic variation and environmental variation. It is obviouslymediated bymolecular and higher-order epigeneticmechanisms. Comparison of SDV in animals, plants, fungi, protists, bacteria, archaeans, and viruses suggests that it is a ubiquitous and phylogenetically old phenomenon. In animals, it is usually smallest for morphometric traits and highest for life history traits and behaviour. SDV is thought to contribute to phenotypic diversity in all populations but is particularly relevant for asexually reproducing and genetically impoverished populations, where it generates individuality despite genetic uniformity. In each generation, SDV produces a range of phenotypes around a well-adapted target phenotype, which is interpreted as a bet-hedging strategy to cope with the unpredictability of dynamic environments. At least some manifestations of SDV are heritable, adaptable, selectable, and evolvable, and therefore, SDV may be seen as a hitherto overlooked evolution factor. SDV is also relevant for husbandry, agriculture, and medicine because most pathogens are asexuals that exploit this third source of phenotypic variation tomodify infectivity and resistance to antibiotics. Since SDV affects all types of organisms and almost all aspects of life, it urgently requires more intense research and a better integration into biological thinking.

Anthropophilic Anopheles species composition and malaria in Tierradentro, Córdoba, Colombia

Malaria is still a primary health problem in Colombia. The locality of Tierradentro is situated in the municipality of Montelíbano, Córdoba, in the northwest of Colombia, and has one of the highest annual parasite index of malaria nationwide. However, the vectors involved in malaria transmission in this locality have not yet been identified. In this study, the local anthropophilic Anopheles composition and natural infectivity with Plasmodium were investigated. In August 2009, 927 female Anopheles mosquitoes were collected in eight localities using the human landing catch method and identified based on their morphology. Cryptic species were determined by restriction fragment length polymorphism-internal transcribed spacer (ITS)2 molecular analysis. Eight species [Anopheles nuneztovari s.l. (92.8%), Anopheles darlingi (5.1%), Anopheles triannulatus s.l. (1.8%), Anopheles pseudopunctipennis s.l. (0.2%), Anopheles punctimacula s.l. (0.2%), Anopheles apicimacula (0.1%), Anopheles albimanus (0.1%) and Anopheles rangeli (0.1%)] were identified and species identity was confirmed by ITS2 sequencing. This is the first report of An. albimanus, An. rangeli and An. apicimacula in Tierradentro. Natural infectivity with Plasmodium was determined by ELISA. None of the mosquitoes was infectious for Plasmodium. An. nuneztovari s.l. was the predominant species and is considered the primary malaria vector; An. darlingi and An. triannulatus s.l. could serve as secondary vectors. .

Relationship between apoptosis and the BH2 domain sequence of the VP5 peptide of infectious pancreatic necrosis virus / Relación entre apoptosis y secuencia del dominio BH2 del peptido VP5 del virus de la necrosis pancreatica infecciosa

Objective. To determine whether the level of apoptosis induced by infectious pancreatic necrosis virus (IPNV) is related to the amino acid sequence of the BH2 domain of the VP5 protein and the level of infectivity. Materials and methods. Three IPNV strains were used, the VP2 protein gene was amplified for genotyping and the VP5 sequence was also obtained. The infectivity of the strains was calculated using the viral titer obtained at 12, 24, 36 and 45 hpi in CHSE-214 cells. The percentage of apoptosis in infected cells was visualized by TUNEL assay and immunohistochemistry (caspase 3 detection). Results. The V70/06 and V33/98 strains corresponded to genotype Sp, while V112/06 to VR-299; the amino acid analysis of the V70/06 strain allows its classification as middle virulent strain and V33/98 and V112/06 strains as low virulent ones; infection with the V112/06 strain produced a lower viral titer (p<0.05). The VP5 gene of the 3 strains showed four homologous domains to Bcl-2, however, the BH2 domain was truncated in V70/06 and V33/98 (12 kDa), being complete (15kDa) in V112/06, which also showed the Trp155 residue, equivalent to Trp188 considered as a critical factor for the function of Bcl-2. The average apoptosis was below 12%, showing no differences between strains (p>0.05). Conclusions. The results showed that the differences in the BH2 sequence of the VP5 protein, infectivity and the VP2 sequence are not associated with the modulation of apoptosis.

Objetivo. Determinar si el nivel de apoptosis inducido por cepas del virus de la necrosis pancreática infecciosa (IPNV) tiene relación con la secuencia aminoacídica del dominio BH2 de la proteína VP5 y el nivel de infectividad. Materiales y métodos. Se utilizaron tres cepas de IPNV; el gen de la proteína VP2 fue amplificado para genotipificación y se obtuvo la secuencia de VP5. La infectividad de las cepas se calculó mediante el título viral obtenido a 12, 24, 36 y 45 hpi en células CHSE-214. Los porcentajes de apoptosis en células infectadas se visualizaron mediante ensayo TUNEL e inmuno-histoquímica (detección de caspasa 3). Resultados. Las cepas V70/06 y V33/98 correspondieron a genotipo Sp, mientras que V112/06 a VR-299; el análisis aminoacídico relacionó a V70/06 como cepa de mediana virulencia y a V33/98 y V112/06 de baja virulencia; la infección con V112/06 produjo menor título viral (p<0.05). El gen VP5 de las 3 cepas presentó los cuatro dominios homólogos a Bcl-2; sin embargo, el dominio BH2 fue truncado en V70/06 y V33/98 (12 kDa); siendo completo (15kDa) en V112/06, que además, presentó el residuo Trp155, equivalente a Trp188 considerado factor crítico para la función de Bcl-2. El promedio de apoptosis fue inferior a 12%, no se observaron diferencias entre cepas (p>0.05). Conclusiones. Los resultados mostraron que las diferencias en la secuencia de BH2 de la proteína VP5, la infectividad y en la secuencia de la proteína VP2 no están asociadas con la modulación de apoptosis.

Evaluation of Infective Property of Recombinant Prion Protein Amyloids in Cultured Cells Overexpressing Cellular Prion Protein

Misfolded isoform of prion protein (PrP), termed scrapie PrP (PrP(Sc)), tends to aggregate into various fibril forms. Previously, we reported various conditions that affect aggregation of recombinant PrP into amyloids. Because amyloidogenesis of PrP is closely associated with transmissible spongiform encephalopathies such as Creutzfeldt-Jakob disease in humans, we investigated infectivity of recombinant PrP amyloids generated in vitro. Using cultured cell lines which overexpress cellular PrP of different species, we measured the level of de novo synthesized PrP(Sc) in cells inoculated with recombinant mouse PrP amyloids. While PrP-overexpressing cells were susceptible to mouse-adapted scrapie prions used as the positive control, demonstrating the species barrier effect, infection with amyloids made of truncated recombinant PrP (PrP[89-230]) failed to form and propagate PrP(Sc) even in the cells that express mouse cellular PrP. This suggests that infectivity of PrP amyloids generated in vitro is different from that of natural prions. Recombinant PrP (89-230) amyloids tested in the current study retain no or a minute level, if any, of prion infectivity.

Viabilidade de urediniósporos de Phakopsora pachyrhizi Sidow na ausência do hospedeiro / Viability of Phakopsora pachyrhizi Sidow under host absence

A ferrugem asiática da soja, tem se apresentado como a principal doença da cultura. O objetivo desse trabalho foi avaliar a viabilidade de urediniósporos do agente causal da ferrugem asiática da soja (Phakopsora pachyrhizi Sidow)na ausência do hospedeiro principal.Para a coleta do inóculo raspou-se a face abaxial de folhas de soja com a presença de pústulas do fungo, utilizando-se pincel de pêlo de camelo e papel vegetal. O inóculo foi armazenado em sala de incubação a 20 ± 20C, no escuro, durante a condução do experimento. Para a realização dos experimentos, 4,0 mg de inóculo foram colocadas em suspensão com 1000 mL de água destilada e 0,5% de tween 20, calibrando-se, em câmara de Newbauer para 3,2 x 104 urediniósporos/mL. Realizaram-se os seguintes experimentos: germinação em água; germinaçãoemágar-água 2%; e infectividade emcasa de vegetação. Após análise dos resultados verificou-se que os urediniósporos do patógenomantiveram a viabilidade durante 11 semanas de armazenamento. A capacidade de germinação dos urediniósporos e a severidade da doença foram reduzidas após 3 semanas de armazenamento. Os urediniósporos armazenados a 20 ± 2oC, por até 11 semanas, foram capazes de causar doença em plantas de soja.

Asian soybean rust has been one of the main foliar diseases of soybean. This study evaluated the viability of Phakopsora pachyrhizi, in the absence of its main host. For the collection of the initial inoculum, the abaxial face of soybean leaveswere scraped, using a camel hair brush over vegetable paper. The inoculum was stored in incubation room at 20 ± 2º C, in the dark. For the experiments, 4.0 mg of inoculum were suspendedin 1000 ml of distilled water and 0.5% of Tween 20, calibrating in chamber of Neubauer chamber to 3.2 x 104 urediniosporesmL-1. The following experiments were done: germination in water; germination in agar-water 2%; and infectivity in a greenhouse. The results showed that urediniospores of the pathogenremained viableduring the 11 weeks storage, the germination of the urediniosporesand the severity of Asian soybean rust were reduced after 3 weeks of storage and the urediniospores stored at 20 ± 2ºC for up to 11 weeks were able to cause disease in soybean plants.

Patogenicidad oral de un aislamiento autóctono del hongo entomopatógeno Beauveria bassiana en ratones (Mus musculus, cepa NMRI) / Oral pathogenicity of an autochthonous isolate of the entomopathogenic fungus Beauveria bassiana in mice (Mus musculus, strain NMRI)

Se evaluó a concentración de 1x10(8) conidias/mL por vía oral en ratones albinos NMRI, la patogenicidad del aislamiento fúngico LF14 de Beauveria bassiana, el cual posee una elevada virulencia hacia Rhodnius prolixus y Triatoma maculata (Triatominae), vectores de enfermedad de Chagas en Venezuela. Se hicieron observaciones clínicas diarias. Se estimó el aclaramiento fúngico mediante examen directo y cultivo de muestras de heces, y de infectividad con la toma de muestras de tejidos y estudio histopatológico. No se registró muertes ni alteraciones clínico-patológicas, y el comportamiento en todos los animales fue activonormal. El peso promedio corporal, tanto en los animales expuestos a LF14 B. bassiana como los controles, se incrementó con el tiempo, siendo sólo las diferencias entre sexos estadísticamente significativas (P<0,0000). Se obtuvieron conidias viables en heces hasta el día 7 después del consumo del hongo. No se detectó anormalidades en la inspección anatomopatológico ni conidias germinadas en ninguno de los órganos estudiados, sin ninguna reacción tisular patológica, sugiriendo que no existe evidencia de multiplicación fúngica. Los resultados obtenidos permiten concluir que el aislamiento LF14 de B. bassiana no es patogénico cuando se administró por vía oral en ratones albinos NMRI.

This study evaluated concentrations of 1x10(8) conidia/mL orally administered in white mice (NMRI strain, males and females), pathogenicity of a native isolate LF14 of Beauveria bassiana (Fungi: Ascomycota), highly virulent to Rhodnius prolixus and Triatoma maculata (Triatominae), vectors of Chagas disease in Venezuela. Clinical evaluations were done daily. Clearance of fungus in the faeces was estimated by direct examination and culturing, and infectivity by performing mycological and histopathological tests.Animals showed no discernible pathological changes or death and had 100% active-normal behaviour. In all the mice groups, including control ones, there was an increase in the mean weight gained through time, with statistically significance difference between the sexes (P<0,0000). Viable conidia were observed in faeces until 7 days after consuming the fungus. Anatomopathological changes or germinated conidia were not detected in analysed organs, with normal tissue reactions, suggesting no evidence for fungal multiplication. Results obtained allowed us to conclude that isolate LF14 B. bassiana orally administered is safe and non pathogenic in white mice (NMRI strain).

Los productos alternativos de LYT1 de Trypanosoma cruzi tienen un patrón de localización diferencial / The alternative products of Trypanosoma cruzi LYT1 have different localization patterns

LYT1 is a molecule with lytic activity under acidic conditions that, as genetically demonstrated, participates in the infection and stage transition of T. cruzi. The differing functions of this protein result from alternative trans-splicing, resulting in proteins that contain either a secretion and nuclear sequence (LYT1s) or the nuclear sequence alone (LYT1n). To determine the localization of different LYT1 products, transgenic parasites expressing LYT1s or LYT1n fused to the enhanced green fluorescence sequence were analyzed. LYT1s-EGFP localized to the flagellum, vacuoles, membrane and regions of the nucleus and kinetoplast; LYT1n-EGFP localized to the nucleus and kinetoplast, and occasionally in vacuoles. These results show that even though different LYT1 products localize to the same sites, they are also found in different intracellular organelles and microenvironments, which could influence their multifunctional behavior.

LYT1 es una molécula con actividad lítica en condiciones ácidas, que según se demostró genéticamente, participa en el proceso de infección y transición de estadio de T. cruzi. Su diferente funcionalidad es resultado de la producción de dos proteínas, obtenidas por trans-empalme alternativo, que contienen una secuencia de secreción y una nuclear (LYT1s) o únicamente la secuencia nuclear (LYT1n). Para evaluar la localización de los diferentes productos de LYT1, se analizaron parásitos transgénicos que expresan la secuencia de LYT1s o LYT1n fusionada con la secuencia de la verde fluorescente. LYT1s-EGFP se localiza en flagelo, vacuolas, membrana y región del núcleo y cinetoplasto; mientras que, LYT1n-EGFP se localiza en la región del núcleo y cinetoplasto, y ocasionalmente en vesículas. Estos resultados muestran que aún cuando los distintos productos de LYT1 comparten algunos sitios de localización, también se encuentran en distintos organelos y microambientes intracelulares que podrían influir en su comportamiento multifuncional.