Enhancing protein extraction from heterotrophic Auxenochlorella protothecoides microalgae through emerging cell disruption technologies combined with incubation.

This study evaluated pulsed electric fields (PEF) and ultrasonication (US) combined with incubation to enhance cell disruption and protein extraction from Auxenochlorella protothecoides, comparing them to conventional high-pressure homogenization (HPH). A 5 h incubation enhanced protein yield by 79.4 % for PEF- and 27.2 % for US-treated samples. Extending the incubation to 24 h resulted in a total yield increase of 122 % for PEF (0.25 ±â€¯0.03 kgEP kgTP-1) and 51.9 % for US. Autofermentation in untreated cells after 24 h resulted in protein release with lower yields than all other treated and incubated samples. While HPH had the highest protein yield (0.58 ±â€¯0.04 kgEP kgTP-1), PEF-incubation after 5 h (56.6 ±â€¯5.3 MJ kgEP-1) and 24 h (49.5 ±â€¯3.7 MJ kgEP-1) were 1.5 and 1.7-times more energy-efficient than HPH (82.9 ±â€¯7.8 MJ kgEP-1). PEF combined incubation is an energy-efficient and targeted protein extraction method in heterotrophic A. protothecoides biorefinery.

Novel Cluster AZ Arthrobacter phages Powerpuff, Lego, and YesChef exhibit close functional relationships with Microbacterium phages.

Bacteriophages exhibit a vast spectrum of relatedness and there is increasing evidence of close genomic relationships independent of host genus. The variability in phage similarity at the nucleotide, amino acid, and gene content levels confounds attempts at quantifying phage relatedness, especially as more novel phages are isolated. This study describes three highly similar novel Arthrobacter globiformis phages-Powerpuff, Lego, and YesChef-which were assigned to Cluster AZ using a nucleotide-based clustering parameter. Phages in Cluster AZ, Microbacterium Cluster EH, and the former Microbacterium singleton Zeta1847 exhibited low nucleotide similarity. However, their gene content similarity was in excess of the recently adopted Microbacterium clustering parameter, which ultimately resulted in the reassignment of Zeta1847 to Cluster EH. This finding further highlights the importance of using multiple metrics to capture phage relatedness. Additionally, Clusters AZ and EH phages encode a shared integrase indicative of a lysogenic life cycle. In the first experimental verification of a Cluster AZ phage's life cycle, we show that phage Powerpuff is a true temperate phage. It forms stable lysogens that exhibit immunity to superinfection by related phages, despite lacking identifiable repressors typically required for lysogenic maintenance and superinfection immunity. The ability of phage Powerpuff to undergo and maintain lysogeny suggests that other closely related phages may be temperate as well. Our findings provide additional evidence of significant shared phage genomic content spanning multiple actinobacterial host genera and demonstrate the continued need for verification and characterization of life cycles in newly isolated phages.

Implementing a vector surveillance-response system for chagas disease control: a 4-year field trial in Nicaragua.

BACKGROUND: Chagas disease is one of the neglected tropical diseases (NTDs). International goals for its control involve elimination of vector-borne transmission. Central American countries face challenges in establishing sustainable vector control programmes, since the main vector, Triatoma dimidiata, cannot be eliminated. In 2012, the Ministry of Health in Nicaragua started a field test of a vector surveillance-response system to control domestic vector infestation. This paper reports the main findings from this pilot study. METHODS: This study was carried out from 2012 to 2015 in the Municipality of Totogalpa. The Japan International Cooperation Agency provided technical cooperation in designing and monitoring the surveillance-response system until 2014. This system involved 1) vector reports by householders to health facilities, 2) data analysis and planning of responses at the municipal health centre and 3) house visits or insecticide spraying by health personnel as a response. We registered all vector reports and responses in a digital database. The collected data were used to describe and analyse the system performance in terms of amount of vector reports as well as rates and timeliness of responses. RESULTS: During the study period, T. dimidiata was reported 396 times. Spatiotemporal analysis identified some high-risk clusters. All houses reported to be infested were visited by health personnel in 2013 and this response rate dropped to 39% in 2015. Rates of insecticide spraying rose above 80% in 2013 but no spraying was carried out in the following 2 years. The timeliness of house visits improved significantly after the responsibility was transferred from a vector control technician to primary health care staff. CONCLUSIONS: We argue that the proposed vector surveillance-response system is workable within the resource-constrained health system in Nicaragua. Integration to the primary health care services was a key to improve the system performance. Continual efforts are necessary to keep adapting the surveillance-response system to the dynamic health systems. We also discuss that the goal of eliminating vector-borne transmission remains unachievable. This paper provides lessons not only for Chagas disease control in Central America, but also for control efforts for other NTDs that need a sustainable surveillance-response system to support elimination.

Effectiveness of Large-Scale Chagas Disease Vector Control Program in Nicaragua by Residual Insecticide Spraying Against Triatoma dimidiata.

Chagas disease is one of the most serious health problems in Latin America. Because the disease is transmitted mainly by triatomine vectors, a three-phase vector control strategy was used to reduce its vector-borne transmission. In Nicaragua, we implemented an indoor insecticide spraying program in five northern departments to reduce house infestation by Triatoma dimidiata. The spraying program was performed in two rounds. After each round, we conducted entomological evaluation to compare the vector infestation level before and after spraying. A total of 66,200 and 44,683 houses were sprayed in the first and second spraying rounds, respectively. The entomological evaluation showed that the proportion of houses infested by T. dimidiata was reduced from 17.0% to 3.0% after the first spraying, which was statistically significant (P < 0.0001). However, the second spraying round did not demonstrate clear effectiveness. Space-time analysis revealed that reinfestation of T. dimidiata is more likely to occur in clusters where the pre-spray infestation level is high. Here we discuss how large-scale insecticide spraying is neither effective nor affordable when T. dimidiata is widely distributed at low infestation levels. Further challenges involve research on T. dimidiata reinfestation, diversification of vector control strategies, and implementation of sustainable vector surveillance.

Colocación de bioprótesis en terreno potencialmente contaminado en la intervención quirúrgica herniaria de urgencia / Placement of bioprosthesis in potentially contaminated areas in emergency surgery

Se estudiaron la totalidad de pacientes intervenidos de forma urgente por complicaciones herniarias. El universo y la muestra estuvieron conformados por dos grandes grupos: en el primero se incluyeron todas las hernias inguinales y crurales y cualquier combinación de estas; predominaron las hernias inguinales en hombres mayores de 61 años; las técnicas más usadas fueron la de Lichtenstein en las variantes protésicas y la de Leo Zimmerman en las tensionadas; el seroma fue la complicación común para las técnicas mencionadas y la recidiva fue mayor en las tensionadas -cuatro casos, para un 4.5 por ciento y, en el segundo, se sumaron todas las hernias incisionales y las de la línea media (umbilicales y epigástricas); el mayor número de intervenciones quirúrgicas correspondió a las hernias umbilicales -69 pacientes-, también en hombres mayores de 61 años; la técnica descrita por Jean Rives fue una de las variantes protésicas, así como la de Mayo-Robson en las tensionadas; el seroma fue la complicación más frecuente en ambas técnicas y la recidiva marcó pauta en las tensionadas -cinco pacientes, para un 8.7 por ciento. En la muestra se evidenció que el uso de las mallas quirúrgicas no ha producido un alza en las complicaciones post-operatorias de origen sépticas sino que, por el contrario, han disminuido considerablemente las recidivas en las intervenciones quirúrgicas de la hernia de urgencia con el uso de la bioprótesis(AU)

Rhodnius prolixus en Nicaragua: distribución geogrßfica, control y vigilancia entre 1998 y 2009 / Rhodnius prolixus in Nicaragua: geographical distribution, control, and surveillance, 1998-2009

OBJETIVO: Presentar la perspectiva general del control de Rhodnius prolixus, el principal vector en la transmisión de la enfermedad de Chagas en Centroamérica, durante el período 1998-2009 en Nicaragua. Describir el control vectorial realizado y presentar la distribución geogrßfica de las localidades infestadas. MÉTODOS: Se estudió y analizó la información disponible en el Ministerio de Salud de Nica ragua. Se visualizó la distribución geogrßfica de R. prolixus mediante el programa visualiza dor de mapas Quantum GIS 1.5.0. RESULTADOS: Se determinó que 59 localidades en 14 municipios de 8 departamentos presen taron antecedentes de infestación con R. prolixus entre 1998 y 2009. La altitud de las locali dades infestadas oscila entre 160 y 1 414 metros sobre el nivel del mar. Se han tratado con mßs de dos ciclos de control químico 56 localidades. En el segundo ciclo de rociamiento se detectó la presencia del vector, pero durante el tercer ciclo no se lo encontró en ninguna localidad. CONCLUSIONES: La mayor concentración geogrßfica de R. prolixus se observó en dos depar tamentos de la región norte: Madriz y Nueva Segovia. La cantidad de localidades infestadas es menor en Nicaragua que en otros países centroamericanos. El control químico ha sido exitoso en las localidades intervenidas, pero es necesario fortalecer el sistema de vigilancia institucio nal y comunitaria tanto para vigilar la reinfestación con R. prolixus como para ampliar la cobertura del control vectorial.

OBJECTIVE: Present an overview of the control of Rhodnius prolixus, the principal vector in the transmission of Chagas' disease in Central America, during the period 1998-2009 in Nicaragua. Describe the vector control carried out and the geographical distribution of the infested localities. METHODS: The available information in Nicaragua's Ministry of Health was studied and analyzed. The geographical distribution of R. prolixus was visualized using the Quantum GIS 1.5.0 map visualization program. RESULTS: It was determined that 59 localities in 14 municipalities of 8 departments had a history of R. prolixus infestation between 1998 and 2009. The altitude of the infested localities ranges between 160 and 1 414 meters above sea level. A total of 56 localities have been treated with more than two cycles of chemical control. The presence of the vector was detected in the second spraying cycle, but it was not found in any locality during the third cycle. CONCLUSIONS: The greatest geographical concentration of R. prolixus was found in two departments in the northern region: Madriz and Nueva Segovia. There were fewer infested localities in Nicaragua than in other Central American countries. Chemical control has been successful in the localities treated, but the institutional and community surveillance system needs to be strengthened to monitor R. prolixusreinfestation and expand vector control coverage.

[Rhodnius prolixus in Nicaragua: geographical distribution, control, and surveillance, 1998-2009]. / Rhodnius prolixus en Nicaragua: distribución geográfica, control y vigilancia entre 1998 y 2009.

OBJECTIVE: Present an overview of the control of Rhodnius prolixus, the principal vector in the transmission of Chagas' disease in Central America, during the period 1998-2009 in Nicaragua. Describe the vector control carried out and the geographical distribution of the infested localities. METHODS: The available information in Nicaragua's Ministry of Health was studied and analyzed. The geographical distribution of R. prolixus was visualized using the Quantum GIS 1.5.0 map visualization program. RESULTS: It was determined that 59 localities in 14 municipalities of 8 departments had a history of R. prolixus infestation between 1998 and 2009. The altitude of the infested localities ranges between 160 and 1 414 meters above sea level. A total of 56 localities have been treated with more than two cycles of chemical control. The presence of the vector was detected in the second spraying cycle, but it was not found in any locality during the third cycle. CONCLUSIONS: The greatest geographical concentration of R. prolixus was found in two departments in the northern region: Madriz and Nueva Segovia. There were fewer infested localities in Nicaragua than in other Central American countries. Chemical control has been successful in the localities treated, but the institutional and community surveillance system needs to be strengthened to monitor R. prolixus reinfestation and expand vector control coverage.