Gaps in African swine fever: Analysis and priorities.

African swine fever (ASF) causes greater sanitary, social and economic impacts on swine herds than many other swine diseases. Although ASF was first described in 1921 and it has affected more than fifty countries in Africa, Europe and South America, several key issues about its pathogenesis, immune evasion and epidemiology remain uncertain. This article reviews the main characteristics of the causative virus, its molecular epidemiology, natural hosts, clinical features, epidemiology and control worldwide. It also identifies and prioritizes gaps in ASF from a horizontal point of view encompassing fields including molecular biology, epidemiology, prevention, diagnosis and vaccine development. The purpose of this review is to promote ASF research and enhance its control.

Isolation of Naegleria fowleri from a domestic water tank associated with a fatal encephalitis in a 4 month-old Venezuelan child.

This study describes the association of household water system contamination with the pathogenic Free-Living Amoeba (FLA) Naegleria fowleri and a case of fatal Primary Amoebic Meningoencephalitis (PAM) in a child from the state of Monagas in Venezuela. Amoebae were initially identified by microscopy from a sample of cerebrospinal fluid (CSF) from the child. Direct DNA extraction and specific PCR/sequencing for N. fowleri was also carried out from the same CSF sample. In order to determine a possible environmental source of infection, water samples from the water tank of the child's home and also water bodies recently visited by the child and his family, were examined for the presence of N. fowleri by culture and PCR/sequencing. The results obtained from the collected water samples revealed that only the water tank of the house was positive for N. fowleri. PCR/sequencing showed that the strains isolated from the patient and the water tanks were 100 % identical. Therefore, the house water tank was confirmed as the source of infection in this case, possibly as a result of the occasional immersion of the child´s head under the water while bathing. This case highlights a novel source of thermally polluted water and another threat of N. fowleri infection.

Balamuthia mandrillaris therapeutic mud bath in Jamaica.

Balamuthia mandrillaris is an emerging cause of encephalitis in humans. The transmission dynamics are poorly understood due to the high fatality rate and the sporadic nature of cases. Seventy-two soil samples were collected from beaches and the banks of lagoons, rivers, ponds, mineral springs and streams from across Jamaica and assayed for the presence of B. mandrillaris. Seventy-nine sites were sampled and the mitochondrial 16S rDNA gene of B. mandrillaris was amplified and sequenced to confirm the presence of the amoeba. One isolate of B. mandrillaris was recovered from soil from mineral spring which hosts an informal therapeutic mud bath business. Although B. mandrillaris is less frequently isolated from soil than other free-living amoebae, rubbing mud containing the organism onto the skin increases the likelihood of exposure and infection. This first report on the isolation of B. mandrillaris in the Caribbean and its presence in soil where human contact is likely warrants further investigation using serological methods to elucidate exposure patterns.

Delayed lung maturation of foetus of diabetic mother rats develop with a diminish, but without changes in the proportion of type I and II pneumocytes, and decreased expression of protein D-associated surfactant factor.

Newborn children of diabetic mothers have an increased morbidity and mortality because of respiratory distress syndrome. We study lung histogenesis during intrauterine development of offspring of diabetic Sprague-Dawley rats at 18, 19 and 21 days of gestation (DG). Pregnant rats were grouped into diabetic (streptozotocin-induced), citrate, and control groups; five female and five male offspring were selected randomly from each group at 18, 19 and 21 DG, and a biopsy of the lung was taken and processed in paraffin for histological examination. The biopsy for the transmission electron microscopy (TEM) analysis was taken at 21 days. A delay in alveolization of the offspring at 18, 19 and 21 days of the diabetic group was observed, which was confirmed at TEM level, and also less quantity of protein D associated to surfactant in diabetic group was detected (P < 0.001). The foetuses of the diabetic group presented a delay in lung histogenesis and in differentiation of the type II pneumocytes cells, but conserved the proportion with a decrease in 50% of pneumocytes, accompanied by a diminish of protein D associated to surfactant factor.

Ionic correlations in the inhomogeneous atmosphere surrounding cylindrical polyions: catalytic effects of polyions.

The structural properties of linear polyelectrolyte solutions in the presence of a salt as evidenced through ionic correlations in the inhomogeneous atmosphere around a polyion and their consequence such as the catalytic potential are studied by using Monte Carlo simulation techniques. The simulations are performed on the cylindrical cell model where a uniformly charged hard cylinder mimics the linear polyion, which is caged in its own cylindrical cell containing counterions and salt. The cell (volume) average of the interionic correlations is presented as a function of the polyion and salt concentrations and ion radius. These results are utilized to study the catalytic effects of polyions as manifested through the changes in the collision frequency between ions in the double layer surrounding the polyion relative to that in the pure electrolyte solution. The reported results suggest a strong influence of the added salt/polyelectrolyte concentration ratio on the structural properties of the solution and hence on ion-ion collision frequency. The machine simulations are supplemented by nonlinear Poisson-Boltzmann results. Fair agreement between two different theoretical methods of calculating the collision frequency is obtained.

Counterion-counterion correlation in the double layer around cylindrical polyions: counterion size and valency effects.

Monte Carlo simulation and Poisson-Boltzmann results on some aspects of structure and thermodynamics of aqueous polyelectrolyte solutions are presented. The polyelectrolyte solution is described by an infinitely long cylindrical polyion surrounded by counterions modeled as rigid ions moving in a continuum dielectric. Ion-ion correlations in the form of volume average of the counterion-counterion distribution function in the double layer surrounding the polyion are reported for mono- and divalent counterions and for a range of polyion concentrations and charge density parameters in each case. These results confirm again strong influence of the charge density parameter of polyions on properties of polyelectrolyte solutions. The structural information is supplemented by the calculated thermodynamic properties such as osmotic coefficients and heats of dilutions; the latter quantity has not been examined yet in detail by computer simulations. The results are discussed in view of the existing experimental data from the literature for these properties.

RAPD method useful for distinguishing Leishmania species: design of specific primers for L. braziliensis.

The technique of Random Amplification Polymorphic DNA allows fragments of the genome to be amplified by means of polymerase chain reaction (PCR) without previous knowledge of their sequences. The protozoa of the genus Leishmania present great genetic variability, making it difficult to characterize the different species. A method is developed with a single 10-mers long primer, which allows the species L. braziliensis, L. mexicana, L. infantum, L. tropica, L. chagasi, L. amazonensis and L. major to be differentiated. These products amplified by RAPD have also facilitated the design of some primers that amplify L. braziliensis DNA exclusively.

Analysis of NLS and rRNA binding motifs in the L25 ribosomal protein from Leishmania (viannia) braziliensis: investigation of its diagnostic capabilities.

A cDNA clone codifying ribosomal protein L25 was isolated from a Leishmania braziliensis cDNA gene library. The alignment of the amino acid sequence deduced from this gene with other proteins revealed that this protein is related to the L23/25 rihosomal protein family. This is so because this protein shows, in its C-terminal end, the rRNA binding domains characteristic of these proteins and at the N-terminal end the NLS sequence necessary for its entry into the nucleus. Southern blot analysis showed 2 copies of gene L25 per genome arranged in tandem position and pointing in the same direction. Northern blot analysis showed that this gene is transcribed in 2 mRNAs when parasite promastigotes are in the logarithmic phase. In order to analyse the antigenic properties of L. braziliensis RPL25, it was purified as a recombinant protein and ELISA-tested against cutaneous, mucocutaneous and Chagasic sera. The results indicate that the recombinant RPL25 from L. braziliensis presents a non-specific reaction that disqualifies it for the diagnosis of cutaneous leishmaniasis. In contrast, some of the synthetic peptides derived from its sequence may serve as promising tools for the diagnosis of this disease.

Small-scale isolation of high molecular weight DNA from Leishmania braziliensis.

In this paper, we report a method for isolation of high molecular weight DNA from Leishmania promastigotes. This technique is especially indicated for small-scale purification of DNA suitable for the construction of highly representative genomic libraries. In our protocol, lysis buffer is compatible with RNase treatment, avoiding an additional precipitation step and consequent shearing of DNA. In order to prove the quality of the DNA isolated by this method, a Leishmania braziliensis genomic library was constructed, and an L. braziliensis KMP-11 gene was cloned after screening the library with a heterologous probe.

Factores de riesgo para la salud y la situación nutricional de los adolescentes urbanos en Argentina / Fatores de risco para a saúde e estado de nutriþõo de adolescentes urbanos na Argentina / Factors of risk for the health and the nutricional situation of the urban adolescents

Se estudiaron 386 adolescentes sanos (58 porciento hombres y 42 porciento mujeres) de la población que concurrió espontaneamente al Servicio de Adolescencia del Hospital Argerich. Las encuestas de hábitos de vida, alimentaria, sacioeconómica y estudios bioquímicos mostraron que 8,5 porciento fumaban regularmente y 3,5 porciento esporádicamente. Del total, 7,6 porciento presentó colesterolemias elevadas (especialmente en el NSE alto), 6 porciento LDL elevado y 10 porciento HDL bajo(AU)

Factores de riesgo para la salud y la situación nutricional de los adolescentes urbanos en Argentina / Fatores de risco para a saúde e estado de nutriçäo de adolescentes urbanos na Argentina / Factors of risk for the health and the nutricional situation of the urban adolescents

Se estudiaron 386 adolescentes sanos (58 porciento hombres y 42 porciento mujeres) de la población que concurrió espontaneamente al Servicio de Adolescencia del Hospital Argerich. Las encuestas de hábitos de vida, alimentaria, sacioeconómica y estudios bioquímicos mostraron que 8,5 porciento fumaban regularmente y 3,5 porciento esporádicamente. Del total, 7,6 porciento presentó colesterolemias elevadas (especialmente en el NSE alto), 6 porciento LDL elevado y 10 porciento HDL bajo

Factores de riesgo para la salud y la situacion nutricional de los adolescentes urbanos en Argentina / Factores de riesgo para la salud y la situacion nutricional de los adolescentes urbanos en Argentina

Foram estudados 386 adolescentes sadios (58 por cento do sexo masculino e 42 por cento do sexo feminino) de uma populacao que procurou espontaneamente o Servico de Adolescencia do Hospital Argerich. O levantamento de estilos de vida, habitos alimentares, condicao socio-economica e estudos bioquimicos mostrou que: 8,5 por cento fumavam regularmente e 3,5 por cento experimentaram eventualmente. Dos adolescentes estudados, 95 por cento desconheciam os riscos relacionados com o fumo. Do total, 7,6 por cento apresentaram hipercolesterolemia (especialmente no grupo de Nivel Socio-Economico - NSE - elevado), 6 por cento com LDL alto e 10 por cento com HDL baixo. Entre os homens 18 por cento e entre as mocas 52 por cento nao realizavam nenhum tipo de atividade fisica sistematica (P < 0.01) e os adolescentes com NSE baixo aplicaram significativamente menor quantidade de energia a atividade fisica (541 Kcal/dia mais ou menos 660 Kcal/dia) comparados com aqueles que apresentavam NSE medio (885 Kcal/dia mais ou menos 1.088 Kcal/dia) e com os que apresentavam NSE alto (948 Kcal/dia mais ou menos 1.044 Kcal/dia) (p < 0.05). Do total, 30 por cento gastavam mais de 4 horas assistindo televisao e 6 por cento apresentaram atraso cronico do crescimento; 19,1 por cento das mulheres e 13,3 por cento dos homens eram obesos. A ingestao calorica media foi de 2.697 mais ou menos 1099 Kcal/dia (gorduras 32 por cento mais ou menos 10 por cento, gorduras saturadas 13 por cento mais ou menos 5 por cento). A ingestao de gorduras e de gorduras saturadas foi significativamente maior naqueles com NSE mais elevado. A metade dos adolescentes nao atingia os niveis recomendaveis de vitamina A e de ferro, 40 por cento de vitamina C e 91 por cento de calcio. A concentracao de retinol foi de 34,1 mais ou menos 9,8 ug/dl, com diferencas de acordo com o estagio puberal, e 3,5 por cento apresentaram deficit de vitamina A. Das mulheres 12,1 por cento e dos homens 8,1 por cento apresentaram anemia. Conclui-se que os adolescentes urbanos apresentam riscos relacionados a elevada prevalencia de obesidade, escassa atividade fisica, em especial nas classes socio-economicas mais baixas, uma alimentacao com alto teor de gorduras, especialmente saturadas, e baixo teor de ingestao de alguns micronutrientes tais como o calcio, o ferro e a vitamina C, deficiencia de ferro e vitamina A e alta prevalencia de fatores de risco cardiovascular, passiveis de modificacao com mudancas no estilo de vida.

Estudio de ciertos factores de riesgo de la salud y de la situación nutricional de adolescentes urbanos / Health risk factors and nutritional status of urban adolescents

Se estudiaron 386 adolescentes (58 por ciento hombres y 42 por ciento mujeres) de la población que concurrió espontáneamente al Servicio de Adolescencia del Hospital Argerich. Se realizaron encuestas de hábitos de vida, alimentaria, socioeconómica y estudios bioquímicos. El 69 por ciento de los adolescentes no utilizaba ningún método anticonceptivo. La mitad de la población consumía alcohol regularmente especialmente en los NSE más bajos; 8.1 por ciento fumaba regularmente y se demostró desconocimiento de los riesgos vinculados con el tabaquismo. 7.6 por ciento presentó colesterolemias elevadas (especialmente en el NSE alto) 6 por ciento LDL elevado y 10 por ciento HDL bajo. El 18 por ciento de los varones y 52 por ciento de las mujeres no practicaba ninguna forma de actividad física sistemática (p<0.01) y los adolescentes del NSE bajo destinaron significativamente menos energía a la actividad física (541 Kcal/día ñ 660 Kcal/día)comparados con sus pares del NSE medio (855 Kcal/día ñ 1088 Kcal/día) y alto (948 Kcal/día ñ 1044 Kcal/día) (p<0.05). El 30 por ciento pasaba más de 4 horas mirando TV, 6 por ciento presentó retraso crónico de crecimiento, 19.1 por ciento de las mujeres y 13.3 por ciento de los varones eran obesos. La ingesta energética media fue 2697 ñ 1099 Kcal/día, (grasas 32 por ciento ñ 10 por ciento, grasas saturadas 13 por ciento ñ 5 por ciento)...

Estudio de ciertos factores de riesgo de la salud y de la situación nutricional de adolescentes urbanos / Health risk factors and nutritional status of urban adolescents

Se estudiaron 386 adolescentes (58 por ciento hombres y 42 por ciento mujeres) de la población que concurrió espontáneamente al Servicio de Adolescencia del Hospital Argerich. Se realizaron encuestas de hábitos de vida, alimentaria, socioeconómica y estudios bioquímicos. El 69 por ciento de los adolescentes no utilizaba ningún método anticonceptivo. La mitad de la población consumía alcohol regularmente especialmente en los NSE más bajos; 8.1 por ciento fumaba regularmente y se demostró desconocimiento de los riesgos vinculados con el tabaquismo. 7.6 por ciento presentó colesterolemias elevadas (especialmente en el NSE alto) 6 por ciento LDL elevado y 10 por ciento HDL bajo. El 18 por ciento de los varones y 52 por ciento de las mujeres no practicaba ninguna forma de actividad física sistemática (p<0.01) y los adolescentes del NSE bajo destinaron significativamente menos energía a la actividad física (541 Kcal/día ñ 660 Kcal/día)comparados con sus pares del NSE medio (855 Kcal/día ñ 1088 Kcal/día) y alto (948 Kcal/día ñ 1044 Kcal/día) (p<0.05). El 30 por ciento pasaba más de 4 horas mirando TV, 6 por ciento presentó retraso crónico de crecimiento, 19.1 por ciento de las mujeres y 13.3 por ciento de los varones eran obesos. La ingesta energética media fue 2697 ñ 1099 Kcal/día, (grasas 32 por ciento ñ 10 por ciento, grasas saturadas 13 por ciento ñ 5 por ciento)...(AU)