Transversus abdominis release (TAR) procedure: a retrospective analysis of an abdominal wall reconstruction group.

Complex abdominal wall defects are important conditions with high morbidity, leading to impairment of patients' physical condition and quality of life. In the last decade, the abdominal wall reconstruction paradigm has changed due to the formation of experienced and excellence groups, improving clinical outcomes after surgery. Therefore, our study shows the perspective and outcomes of an abdominal wall reconstruction group (AWRG) in Colombia, focused on the transverse abdominis release (TAR) procedure. A retrospective review of a prospectively collected database was conducted. All the patients older than 18 years old that underwent TAR procedures between January 2014-December 2020 were included. Analysis and description of postoperative outcomes (recurrence, surgical site infection (SSI), seroma, hematoma, and re-intervention) were performed. 47 patients underwent TAR procedure. 62% of patients were male. Mean age was 55 ± 13.4 years. Mean BMI was 27.8 ± 4.5 kg/m2. Abdominal wall defects were classified with EHS ventral Hernia classification having a W3 hernia in 72% of all defects (Mean gap size of 11.49 cm ± 4.03 cm). Mean CeDAR preoperative risk score was 20.5% ± 14.5%. Preoperative use of BOTOX Therapy (OR 1.0 P 0.00 95% CI 0.3-1.1) or pneumoperitoneum (OR 0.7 P 0.04 95% CI 0.3-0.89) are slightly associated with postoperative hematoma. In terms of hernia relapse, we have 12% of cases; all of them over a year after the surgery. TAR procedure for complex abdominal wall defects under specific clinical conditions including emergency scenarios is viable. Specialized and experienced groups show better postoperative outcomes; further studies are needed to confirm our results.

Impact of the COVID-19 pandemic on laboratory diagnosis of tuberculosis in southern Brazil / Impacto da pandemia de COVID-19 no diagnóstico laboratorial de tuberculose no sul do Brasil / Impacto de la pandemia COVID-19 en el diagnóstico de laboratorio de la tuberculosis en el sur de Brasil

Background and objectives: to understand the impact of the COVID-19 pandemic on tuberculosis (TB) diagnosis in different settings is essential to guide the establishment of appropriate TB control strategies. This study aimed to assess the influence of COVID-19 pandemic in laboratory diagnosis of TB in patients tested and diagnosed for TB. Methods: a data survey was carried out in the database of laboratories that perform TB diagnosis for the public health system in Rio Grande city (Rio Grande do Sul, Brazil). Results: there was a decrease of 1,368 to 735 (reduction of 46.3%) in the number of patients tested for TB in public diagnostic services in 2019 and 2020, respectively, and a decrease of 197 to 119 (reduction of 39.6%) in the number of new TB cases diagnosed. In contrast, the positivity rate was 14.4% in 2019 and 16.2% in 2020. Moreover, it was observed that the laboratory that performs the diagnostic service for Primary Health Care was the most affected, when compared to Tertiary Health Care. Conclusion: as a consequence of measures to control the spread of SARS-CoV-2, there was a reduction in TB testing and in the detection of new cases, especially in Primary Health Care, where patients with less need for hospitalization are received.(AU)

Justificativa e objetivos: compreender o impacto da pandemia COVID-19 no diagnóstico da tuberculose (TB) em diferentes locais é essencial para orientar o estabelecimento de estratégias adequadas de controle da TB. O objetivo deste estudo foi avaliar a influência da pandemia de COVID-19 no diagnóstico laboratorial de TB, em pacientes testados e diagnosticados com TB. Métodos: foi realizado um levantamento de dados no banco de dados de laboratórios que realizam diagnóstico de TB para o sistema público de saúde na cidade de Rio Grande (Rio Grande do Sul, Brasil). Resultados: houve redução de 1.368 para 735 (redução de 46,3%) no número de pacientes testados para TB nos serviços públicos de diagnóstico em 2019 e 2020, respectivamente, e redução de 197 para 119 (redução de 39,6%) no número de novos casos de TB diagnosticados. Em contrapartida, a taxa de positividade foi de 14,4% em 2019 e 16,2% em 2020. Além disso, observou-se que o laboratório que realiza o serviço de diagnóstico para a Atenção Primária à Saúde foi o mais afetado, quando comparado com a Atenção Terciária à Saúde. Conclusão: como consequência das medidas de controle da disseminação do SARS-CoV-2, houve redução na testagem de TB e na detecção de novos casos, principalmente na atenção primária à saúde, onde são recebidos pacientes com menor necessidade de internação.(AU)

Justificación y objetivos: comprender el impacto de la pandemia Covid-19 en el diagnóstico de tuberculosis (TB) en diferentes lugares es fundamental para orientar el establecimiento de estrategias adecuadas de control de la TB. El objetivo de este estudio fue evaluar la influencia de la pandemia de COVID-19 en el diagnóstico de laboratorio de TB, en términos de pacientes examinados y diagnosticados de TB. Métodos: los datos fueron recolectados de la base de datos de los laboratorios que realizan el diagnóstico de TB para el sistema público de salud en la ciudad de Rio Grande (Rio Grande do Sul, Brasil). Resultados: hubo una reducción de 1.368 a 735 (reducción del 46,3%) en el número de pacientes sometidos a pruebas de TB en los servicios públicos de diagnóstico en 2019 y 2020, respectivamente, y una reducción de 197 a 119 (reducción del 39,6%) en el número de nuevos casos de TB diagnosticados. Por otro lado, la tasa de positividad fue de 14,4% en 2019 y 16,2% en 2020. Además, se observó que el laboratorio que realiza el servicio de diagnóstico para la Atención Primaria de Salud fue el más afectado, en comparación con la Atención Terciaria de Salud. Conclusiones: como consecuencia de las medidas para el control de la propagación del SARS-CoV-2, hubo una reducción en las pruebas de TB y en la detección de nuevos casos, especialmente en la Atención Primaria de Salud, donde se encuentran los pacientes con menor necesidad de hospitalización.(AU)

Fundamentos para un currículo nacional en Cirugía General basado en competencia: Consenso Delphi de la División de Educación de la Asociación Colombiana de Cirugía / Foundations for a national competence-based curriculum in General Surgery: Delphi Consensus of the Division of Education of the Colombian Association of Surgery

Frente a los desafíos de la Educación Basada en Competencia, este consenso Delphi de la División de Educación de la Asociación Colombiana de Cirugía informa sobre las mínimas competencias profesionales esperadas del cirujano egresado de los veinte programas de Especialización en Cirugía General en Colombia. Un total de 105 profesores de los programas de especialización evaluaron tres áreas de competencia profesional: 1) atributos profesionales generales del residente durante su formación, 2) competencias prácticas (procedimientos quirúrgicos) que los residentes deben realizar al final de su entrenamiento y 3) Actividades Profesionales Confiables (APC) que los residentes deben ejecutar sin supervisión al final de su entrenamiento. Los resultados informan un alto nivel de consenso en el 100 % los atributos profesionales generales y APC, y del 75 % en diferentes procedimientos quirúrgicos. El consenso abre la puerta para el desarrollo de un currículo nacional de la especialidad y tiene implicaciones para la práctica educativa e investigación futura

Faced with the challenges of Competence-Based Education, this Delphi consensus from the Education Division of the Colombian Association of Surgery reports on the minimum professional competencies expected of the surgeon who graduated from the twenty residency programs in General Surgery in Colombia. A total of 105 professors from the training programs evaluated three areas of professional competence: 1) general professional attributes of the resident during their training, 2) practical skills (surgical procedures) that residents must perform at the end of their training, and 3) Activities Trusted Professionals (APC) that residents must run unsupervised at the end of their training. The results report a high level of consensus in 100% general professional attributes and APC, and 75% in different surgical procedures. The consensus opens the door for the development of a national specialty curriculum and has implications for educational practice and future research

Fundamentos para un currículo nacional en Cirugía General basado en competencia: Consenso Delphi de la División de Educación de la Asociación Colombiana de Cirugía / Foundations for a national competence-based curriculum in General Surgery: Delphi Consensus of the Division of Education of the Colombian Association of Surgery

Frente a los desafíos de la Educación Basada en Competencia, este consenso Delphi de la División de Educación de la Asociación Colombiana de Cirugía informa sobre las mínimas competencias profesionales esperadas del cirujano egresado de los veinte programas de Especialización en Cirugía General en Colombia. Un total de 105 profesores de los programas de especialización evaluaron tres áreas de competencia profesional: 1) atributos profesionales generales del residente durante su formación, 2) competencias prácticas (procedimientos quirúrgicos) que los residentes deben realizar al final de su entrenamiento y 3) Actividades Profesionales Confiables (APC) que los residentes deben ejecutar sin supervisión al final de su entrenamiento. Los resultados informan un alto nivel de consenso en el 100 % los atributos profesionales generales y APC, y del 75 % en diferentes procedimientos quirúrgicos. El consenso abre la puerta para el desarrollo de un currículo nacional de la especialidad y tiene implicaciones para la práctica educativa e investigación futura

Faced with the challenges of Competence-Based Education, this Delphi consensus from the Education Division of the Colombian Association of Surgery reports on the minimum professional competencies expected of the surgeon who graduated from the twenty residency programs in General Surgery in Colombia. A total of 105 professors from the training programs evaluated three areas of professional competence: 1) general professional attributes of the resident during their training, 2) practical skills (surgical procedures) that residents must perform at the end of their training, and 3) Activities Trusted Professionals (APC) that residents must run unsupervised at the end of their training. The results report a high level of consensus in 100% general professional attributes and APC, and 75% in different surgical procedures. The consensus opens the door for the development of a national specialty curriculum and has implications for educational practice and future research

Role of Interleukin-6 in Vascular Health and Disease.

IL-6 is usually described as a pleiotropic cytokine produced in response to tissue injury or infection. As a pro-inflammatory cytokine, IL-6 activates innate and adaptative immune responses. IL-6 is released in the innate immune response by leukocytes as well as stromal cells upon pattern recognition receptor activation. IL-6 then recruits immune cells and triggers B and T cell response. Dysregulated IL-6 activity is associated with pathologies involving chronic inflammation and autoimmunity, including atherosclerosis. However, IL-6 is also produced and released under beneficial conditions, such as exercise, where IL-6 is associated with the anti-inflammatory and metabolic effects coupled with physical adaptation to intense training. Exercise-associated IL-6 acts on adipose tissue to induce lipogenesis and on arteries to induce adaptative vascular remodeling. These divergent actions could be explained by complex signaling networks. Classical IL-6 signaling involves a membrane-bound IL-6 receptor and glycoprotein 130 (gp130), while trans-signaling relies on a soluble version of IL-6R (sIL-6R) and membrane-bound gp130. Trans-signaling, but not the classical pathway, is regulated by soluble gp130. In this review, we discuss the similarities and differences in IL-6 cytokine and myokine signaling to explain the differential and opposite effects of this protein during inflammation and exercise, with a special focus on the vascular system.

Multifunctional magnetite nanoparticles to enable delivery of siRNA for the potential treatment of Alzheimer's.

Therapeutic drugs for Alzheimer's disease have been extensively studied due to its recurrence and abundance among neurodegenerative diseases. It is thought that the accumulation of amyloid precursor protein (APP) products, a consequence of an up-regulation of the ß-site APP-cleaving enzyme 1 (BACE1), is the main triggering mechanism during the early stages of the disease. This study aims to explore the ability of a multifunctional conjugate based on magnetite nanoparticles for the cellular delivery of siRNA against the expression of the BACE1 gene. We immobilized the siRNA strand on PEGylated magnetite nanoparticles and investigated the effects on biocompatibility and efficacy of the conjugation. Similarly, we co-immobilized the translocating protein OmpA on PEGylated nanoparticles to enhance cellular uptake and endosomal escape. BACE1 suppression was statistically significant in HFF-1 cells, without any presence of a cytotoxic effect. The delivery of the nanoconjugate was achieved through endocytosis pathways, where endosome formation was likely escaped due to the proton-sponge effect characteristic of PEGylated nanoparticles or mainly by direct translocation in the case of OmpA/PEGylated nanoparticles.

Educación quirúrgica durante la pandemia de COVID-19: primer consenso nacional de la División de Educación de la Asociación Colombiana de Cirugía / Surgical education during the COVID-19 pandemic: First national consensus of the Education Division of the Colombian Association of Surgery

Este consenso presenta las recomendaciones de la División de Educación de la Asociación Colombiana de Cirugía para los programas de especialización en cirugía general del país, con el fin de enfrentar la pandemia de la COVID-19 en los próximos años. Las recomendaciones se formularon mediante un método informal de consenso de expertos conformado por todos los directores de los programas de especialización en cirugía general en Colombia. Las principales recomendaciones se relacionan con los procesos de selección en los programas, investigación, bioseguridad, vigilancia de volumen operatorio, evaluación, simulación y virtualidad, rotaciones especiales, esquemas de trabajo y evaluación de la calidad programática

This consensus presents the recommendations of the División de Educación of the Asociación Colombiana de Cirugía for the Colombian surgical residency programs, in order to face the COVID-19 pandemic in the coming years. The recommendations were formulated using an informal method of consensus of experts made up of all program directors of residency programs in the country. The main recommendations are related to the selection processes in the programs, research, biosecurity, surveillance of operative volume, evaluation, simulation and virtual education, special rotations, work schemes and evaluation of program quality.

Polyphenolic Characterization, Antioxidant, and Cytotoxic Activities of Mangifera indica Cultivars from Costa Rica.

The phenolic profile of skin and flesh from Manifera indica main commercial cultivars (Keitt and Tommy Atkins) in Costa Rica was studied using ultra performance liquid chromatography coupled with high resolution mass spectrometry (UPLC-ESI-MS) on enriched phenolic extracts. A total of 71 different compounds were identified, including 32 gallates and gallotannins (of different polymerization degree, from galloyl hexose monomer up to decagalloyl hexoses and undecagalloyl hexoses); seven hydroxybenzophenone (maclurin and iriflophenone) derivatives, six xanthonoids (including isomangiferin and mangiferin derivatives); 11 phenolic acids (hydroxybenzoic and hydroxycinnamic acid derivatives); and eight flavonoids (rhamnetin and quercetin derivatives). The findings for T. Atkins skin constitute the first report of such a high number and diversity of compounds. Also, it is the first time that the presence of gallotannin decamers and undecamers are reported in the skin and flesh of Keitt cultivar and in T. Atkins skins. In addition, total phenolic content (TPC) was measured with high values especially for fruits' skins, with a TPC of 698.65 and 644.17 mg gallic acid equivalents/g extract, respectively, for Keitt and T. Atkins cultivars. Antioxidant potential using 2,2-diphenyl-1-picrylhidrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) methods were evaluated, with T. Atkins skin showing the best values for both DPPH (IC50 = 9.97 µg/mL) and ORAC (11.02 mmol TE/g extract). A significant negative correlation was found for samples between TPC and DPPH antioxidant values (r = -0.960, p < 0.05), as well as a significant positive correlation between TPC and ORAC (r = 0.910, p < 0.05) and between DPPH and ORAC antioxidant methods (r = 0.989, p < 0.05). Also, cytotoxicity was evaluated in gastric adenocarcinoma (AGS), hepatocarcinoma (HepG2), and colon adenocarcinoma (SW620), with T. Atkins skin showing the best results (IC50 = 138-175 µg/mL). Finally, for AGS and SW 620 cell lines particularly, a high significant negative correlation was found between cytotoxic activity and gallotannins (r = -0.977 and r = -0.940, respectively) while for the HepG2 cell line, the highest significant negative correlation was found with xanthonoids compounds (r = -0.921).

Polyphenolic Characterization and Antioxidant Activity of Malus domestica and Prunus domestica Cultivars from Costa Rica.

The phenolic composition of skin and flesh from Malus domestica apples (Anna cultivar) and Prunus domestica plums (satsuma cultivar) commercial cultivars in Costa Rica, was studied using Ultra Performance Liquid Chromatography coupled with High Resolution Mass Spectrometry (UPLC-DAD-ESI-MS) on enriched-phenolic extracts, with particular emphasis in proanthocyanidin and flavonoids characterization. A total of 52 compounds were identified, including 21 proanthocyanidins ([(+)-catechin and (-)-epicatechin]) flavan-3-ols monomers, five procyanidin B-type dimers and two procyanidin A-type dimers, five procyanidin B-type trimers and two procyanidin A-type trimers, as well as one procyanidin B-type tetramer, two procyanidin B-type pentamers, and two flavan-3-ol gallates); 15 flavonoids (kaempferol, quercetin and naringenin derivatives); nine phenolic acids (protochatechuic, caffeoylquinic, and hydroxycinnamic acid derivatives); five hydroxychalcones (phloretin and 3-hydroxyphloretin derivatives); and two isoprenoid glycosides (vomifoliol derivatives). These findings constitute the first report of such a high number and diversity of compounds in skins of one single plum cultivar and of the presence of proanthocyanidin pentamers in apple skins. Also, it is the first time that such a large number of glycosylated flavonoids and proanthocyanidins are reported in skins and flesh of a single plum cultivar. In addition, total phenolic content (TPC) was measured with high values observed for all samples, especially for fruits skins with a TPC of 619.6 and 640.3 mg gallic acid equivalents/g extract respectively for apple and plum. Antioxidant potential using 2,2-diphenyl-1-picrylhidrazyl (DPPH) and oxygen radical absorbance capacity (ORAC) methods were evaluated, with results showing also high values for all samples, especially again for fruit skins with IC50 of 4.54 and 5.19 µg/mL (DPPH) and 16.8 and 14.6 mmol TE/g (ORAC) respectively for apple and plum, indicating the potential value of these extracts. Significant negative correlation was found for both apple and plum samples between TPC and DPPH antioxidant values, especially for plum fruits (R = -0.981, p < 0.05) as well as significant positive correlation between TPC and ORAC, also especially for plum fruits (R = 0.993, p < 0.05) and between both, DPPH and ORAC antioxidant methods (R = 0.994, p < 0.05).

Flavonoids and Ellagitannins Characterization, Antioxidant and Cytotoxic Activities of Phyllanthus acuminatus Vahl.

The phenolic composition of leaves from Phyllanthus acuminatus L., a plant commonly used in Costa Rica as traditional medicine, was studied using UPLC-ESI-MS on an enriched phenolic extract. A total of 20 phenolic compounds were identified, comprising eight flavonoids (two flavanones-pinocembrin isomers and six derivatives from apigenin, chrysin, quercetin, and kaempferol); seven ellagitannins, two flavan-3-ols (prodelphinidin B dimer and (epi)gallocatechin); and three phenolic acids (ellagic acid, trimethylellagic acid, and ferulic acid). All of these compounds are reported for the first time in P. acuminatus, while previously reported in the genus Phyllanthus. Antioxidant evaluation was performed for P. acuminatus phenolic extract obtaining DPPH results with a remarkably low IC50 value of 0.15 µg/mL. Also, cytotoxicity on gastric AGS and colon SW20 adenocarcinoma cell lines was evaluated, and highly promising results were obtained, with IC50 values of 11.3 µg/mL and 10.5 µg/mL, respectively. Furthermore, selectivity index values obtained when comparing cytotoxicity on normal Vero cells was SI > 20 for both cancer cell lines, indicating a particularly high selectivity. Additionally, Justicidin B, a metabolite extensively studied for its antitumoral activity, was isolated from a non-polar extract of P. acuminatus, and comparatively evaluated for both bioactivities. The DPPH value obtained for Justicidin B was moderate (IC50 = 14.28 µg/mL), while cytotoxicity values for both AGS (IC50 = 19.5 µg/mL) and SW620 (IC50 = 24.8 µg/mL) cell lines, as well as selectivity when compared with normal Vero cells (SI = 5.4 and 4.2 respectively), was good, but lower than P. acuminatus extract. These preliminary results suggest that P. acuminatus enriched phenolic extract containing flavonoids, ellagitannins, flavan-3-ols, and phenolic acids, reported for the first time in this plant, could be of interest for further cancer cytotoxicity studies to elucidate structure-bioactivity relationships, and the molecular mechanisms and pathways.

La transformación de la universidad y los dispositivos de cuantificación / University transformation and quantification devices

Las políticas de Educación Superior en Chile les demandan a las Universidades la instalación de dispositivos de gestión orientados a organizar, cuantificar y monitorear el trabajo académico. Pensando en las implicaciones del uso de estos dispositivos de gestión, este trabajo presenta los resultados de un análisis discursivo de 95 documentos de trabajo (Reglamentos, Bases de concurso, Formularios de acreditación) para conocer las interpelaciones que realiza a la labor universitaria. Mediante el método de análisis de discurso, se caracteriza la actuación de los documentos oficiales que regulan y transforman el trabajo académico. El estudio realizado evidencia que los dispositivos de gestión del Trabajo académico performan el trabajo mediante acciones tales como: establecer jerarquías entre las múltiples tareas de un académico y entre académicos, mediante criterios que no han sido discutidos por la comunidad profesional; objetivar procesos laborales y asumir consensos en torno a ello, desconociendo disputas y desacuerdos actuales; omitir el contexto de producción académica, construyendo una imagen del trabajo como proceso individual; y finalmente instando relaciones laborales individualizadas y competitivas.

In Chile, higher education policies have required universities to adopt management tools related to the monitoring and quantification of academic work. Accordingly, this paper presents the results of a documentary study of 95 official documents concerning academic work (Regulations, Scholarship and Grant Application Guidelines and Accreditation Application Forms) in order to understand the regulations pertaining to academic work. Discourse analysis was used to determine how these documents are used in the university environment to regulate and transform the academic work. The present study shows that management tools adopted characterize the academic work through actions such as: establish hierarchies among the multiple tasks of a faculty member and among faculty members using criteria that have not been discussed by the academic community; objectify work processes and reach consensus over them, disregarding current disputes and disagreements; omit the context of academic production creating an image of work as an individual process; and finally urge the establishment of individualizing and competitive work relationships.

Desgaste profesional en residentes colombianos de cirugía: resultados de un estudio nacional / Professional burnout in Colombian surgical residents: results of a national study

Objetivo. El síndrome de desgaste profesional es una entidad muy prevalente en cirujanos que tiene un impacto negativo en los resultados clínicos y educativos. El objetivo del estudio fue determinar la prevalencia del síndrome de desgaste profesional en residentes colombianos de cirugía, y su variación en función de la edad, el sexo, el tipo de programa, el año de residencia y la región geográfica. Métodos. Se utilizó el Maslach Burnout InventoryHuman Services Survey (MBI-HSS) en 202 residentes. Se calculó el porcentaje global de síndrome de desgaste profesional. Se realizaron análisis univariados para el puntaje global del MBI-HSS y sus subescalas en función de los factores propuestos, y multivariado para evaluar su independencia. Resultados. La prevalencia del síndrome de desgaste profesional fue de 33,15 %. No se encontraron diferencias significativas entre el puntaje global y el de las subescalas del MBI-HSS entre residentes con síndrome de desgaste profesional y sin él, de acuerdo con las variables propuestas. La prevalencia del síndrome de desgaste profesional fue mayor en los programas del centro del país (OR=4,76; IC95% 2,0-11,2). Conclusiones. El síndrome de desgaste profesional en residentes colombianos de cirugía es una entidad prevalente que no se relaciona con la edad, el sexo, el tipo de programa ni el año de residencia. Existen variaciones regionales que indican un mayor riesgo de síndrome de desgaste profesional entre los residentes de los programas del centro del país, las cuales deben explorarse en profundidad

Objectives: The Burnout Syndrome (BS), a highly prevalent entity among surgeons, holds negative impact on clinical and educational outcomes. Our aim was to measure the prevalence of BS in Colombian surgical residents, and their variation according to age, gender, type of program, level of residence and geographic region. Methods: The MBI-Human Services Survey (MBI-HSS) was administered to 202 surgical residents. The overall percentage of BS was calculated. Univariate analyses were performed for the global score of the MBI-HSS and its subscales according to the proposed variables, and multivariate analyses were conducted in order to assess their independence. Results: The prevalence of BS was 33.15%. No significant difference was found in the global and sub-scores of the MBI-HSS between residents with BS and no BS according the proposed variables. The prevalence of BS was higher in the central region of the country (OR 4.76 IC95% 2.0-11.2). Conclusions: BS in Colombian surgical residents is a prevalent entity, which is not related to age, gender, and type of program or level of residence. There are regional variations indicating a higher risk of BS among active residents in programs in the central region of the country, which requires further studies

Final opportunity to rehabilitate an urban river as a water source for Mexico City.

The aim of this study was to evaluate the amount and quality of water in the Magdalena-Eslava river system and to propose alternatives for sustainable water use. The system is the last urban river in the vicinity of Mexico City that supplies surface water to the urban area. Historical flow data were analyzed (1973-2010), along with the physicochemical and bacteriological attributes, documenting the evolution of these variables over the course of five years (2008-2012) in both dry and rainy seasons. The analyses show that the flow regime has been significantly altered. The physicochemical variables show significant differences between the natural area, where the river originates, and the urban area, where the river receives untreated wastewater. Nutrient and conductivity concentrations in the river were equivalent to domestic wastewater. Fecal pollution indicators and various pathogens were present in elevated densities, demonstrating a threat to the population living near the river. Estimates of the value of the water lost as a result of mixing clean and contaminated water are presented. This urban river should be rehabilitated as a sustainability practice, and if possible, these efforts should be replicated in other areas. Because of the public health issues and in view of the population exposure where the river flows through the city, the river should be improved aesthetically and should be treated to allow its ecosystem services to recover. This river represents an iconic case for Mexico City because it connects the natural and urban areas in a socio-ecological system that can potentially provide clean water for human consumption. Contaminated water could be treated and reused for irrigation in one of the green areas of the city. Wastewater treatment plants and the operation of the existing purification plants are urgent priorities that could lead to better, more sustainable water use practices in Mexico City.

Expanding a dynamic flux balance model of yeast fermentation to genome-scale.

BACKGROUND: Yeast is considered to be a workhorse of the biotechnology industry for the production of many value-added chemicals, alcoholic beverages and biofuels. Optimization of the fermentation is a challenging task that greatly benefits from dynamic models able to accurately describe and predict the fermentation profile and resulting products under different genetic and environmental conditions. In this article, we developed and validated a genome-scale dynamic flux balance model, using experimentally determined kinetic constraints. RESULTS: Appropriate equations for maintenance, biomass composition, anaerobic metabolism and nutrient uptake are key to improve model performance, especially for predicting glycerol and ethanol synthesis. Prediction profiles of synthesis and consumption of the main metabolites involved in alcoholic fermentation closely agreed with experimental data obtained from numerous lab and industrial fermentations under different environmental conditions. Finally, fermentation simulations of genetically engineered yeasts closely reproduced previously reported experimental results regarding final concentrations of the main fermentation products such as ethanol and glycerol. CONCLUSION: A useful tool to describe, understand and predict metabolite production in batch yeast cultures was developed. The resulting model, if used wisely, could help to search for new metabolic engineering strategies to manage ethanol content in batch fermentations.

Successful treatment of Nocardia actinomycetoma with meropenem and amikacin combination therapy.

BACKGROUND: Actinomycetomas are chronic, granulomatous, subcutaneous infections caused by the traumatic inoculation of actinomycetes bacteria into the skin which produces nodular lesions with draining sinuses and discharging grains. Actinomycetomas can cause profound disability, and despite long-term chemotherapy, treatment failure is common. AIMS: We investigated the efficacy of a novel drug regimen for the treatment of a severe case of Nocardia actinomycetoma of the leg. MATERIAL AND METHODS: A 31-year-old man was treated with an initial three-week parenteral course of meropenem and amikacin combination therapy followed by long term oral sulphonamides. RESULTS: Treatment was well-tolerated with no adverse effects, and there was complete clinical and microbiological cure with no recurrence. CONCLUSION: Meropenem and amikacin combination therapy represents an important addition to the currently available treatments for actinomycetomas.