Circulating extracellular vesicles in Systemic Lupus Erythematosus: physicochemical properties and phenotype.

OBJECTIVE: This study aimed to identify the physicochemical and phenotypic characteristics of circulating Extracellular Vesicles (EVs) in the plasma of patients with SLE, with or without Lupus Nephritis (LN), and their potential utility as disease biomarkers. METHODS: Plasma-circulating EVs were concentrated using differential centrifugation from adult female patients (n=38) who met the 'American College of Rheumatology/European Alliance of Associations for Rheumatology 2019' criteria for SLE diagnosis with (LN) or without LN (nLN), confirmed by renal biopsy. Controls (n=18) were healthy volunteers matched by gender and similar age. The structure, size and Energy Dispersion Spectrum (EDS) of EVs were observed by electron microscopy. The surface charge and size distribution were evaluated using dynamic light scattering. The counts and phenotype of EVs from patients (SLE-EVs) and controls (Ctrl-EVs) were obtained using flow cytometry. Non-parametric statistical tests and exploratory analysis of multiple variables were performed. The discriminatory power of some variables as potential biomarkers of the disease was also evaluated. RESULTS: Circulating EVs were heterogeneous in morphology and size, but SLE-EVs reached larger diameters than Ctrl-EVs (p<0.0001). Small SLE-EVs and large SLE-EVs were increased compared with Ctrl-EV (p<0.0001 and p<0.05, respectively). Likewise, patients with SLE (LN or nLN) had higher concentrations of large EVs compared with controls (p<0.001 and p<0.0001, respectively). SLE-EVs showed a different EDS (p<0.001) and were less electronegative (p<0.0001) than Ctrl-EVs. EV-CD45+, EV-CD14+ and EV-IgM+ were more frequent in patients with SLE compared with controls (p<0.001, p<0.05 and p<0.001, respectively). The concentrations of large EVs and EV-IgM+ allowed better discrimination of patients from controls. CONCLUSIONS: Plasma-circulating EVs from patients with SLE with and without nephritis are increased in peripheral blood and have different physicochemical properties than controls. Characteristics of EVs such as larger size and the presence of IgM on the surface could help discriminate patients from controls.

Accessibility to palliative care services in Colombia: an analysis of geographic disparities.

OBJECTIVES: Due to the increase in the prevalence of non-communicable diseases and the Colombian demographic transition, the necessity of palliative care has arisen. This study used accessibility and coverage indicators to measure the geographic barriers to palliative care. METHODS: Population-based observational study focused on urban areas and adult population from Colombia, which uses three measurements of geographic accessibility to services: a) density of palliative care services per 100,000 inhabitants, b) analysis of geographic distribution by territorial nodes of the country, and c) spatial analysis of palliative care services using Voronoi diagrams. ArcGIS Pro software was used to map services' locations and identify geographic disparities. RESULTS: A total of 504 palliative care services were identified, of which 77% were primary health care services. The density of palliative care services in Colombia is 1.8 primary care services per 100,000 inhabitants and 0.4 specialized services per 100,000 inhabitants. The average palliative care coverage is 41%, two regions of the country have a coverage below 30%. Twenty-eight percent of the services provide care for a population greater than 50,000 inhabitants within their coverage area, exceeding the acceptable limit by international standards. CONCLUSIONS: Palliative care services are concentrated in three main regions (Bogotá D.C., the Center, and the Caribbean) and are limited in the Orinoquia and Amazonia nodes. Density of specialized palliative care services is extremely low and there are regions without palliative services for adults with palliative needs.

Batch and semi-continuous treatment of cassava wastewater using microbial fuel cells and metataxonomic analysis.

The treatment of agroindustrial wastewater using microbial fuel cells (MFCs) is a technological strategy to harness its chemical energy while simultaneously purifying the water. This manuscript investigates the organic load effect as chemical oxygen demand (COD) on the production of electricity during the treatment of cassava wastewater by means of a dual-chamber microbial fuel cell in batch mode. Additionally, specific conditions were selected to evaluate the semi-continuous operational mode. The dynamics of microbial communities on the graphite anode were also investigated. The maximum power density delivered by the batch MFC (656.4 µW m - 2 ) was achieved at the highest evaluated organic load (6.8 g COD L - 1 ). Similarly, the largest COD removal efficiency (61.9%) was reached at the lowest organic load (1.17 g COD L - 1 ). Cyanide degradation percentages (50-70%) were achieved across treatments. The semi-continuous operation of the MFC for 2 months revealed that the voltage across the cell is dependent on the supply or suspension of the organic load feed. The electrode polarization resistance was observed to decreases over time, possibly due to the enrichment of the anode with electrogenic microbial communities. A metataxonomic analysis revealed a significant increase in bacteria from the phylum Firmicutes, primarily of the genus Enterococcus.

[Strategies and recommendations to face respiratory syncytial virus disease in 2024]. / Estrategias y recomendaciones para enfrentar la enfermedad por virus respiratorio sincicial el año 2024.

During the winter of 2023, Chile faced a complex situation related to the respiratory syncytial virus (RSV). After experiencing a decline in RSV circulation during the years of the SARS-CoV-2 pandemic, a late outbreak was observed in the spring of 2022 and an early onset of the outbreak in 2023, with a significant increase in the number of serious cases. The ineffectiveness of strategic planning and risk communication contributed to the complexity of the situation. To avoid the above next winter, measures such as active surveillance, unification of definitions for acute respiratory infections, identification of RSV variants, public education about infections and advance preparation regarding hospital beds and health personnel are suggested. The importance of immunization and intersectoral collaboration to acquire new preventive alternatives is highlighted, as well as the need for early communication about the importance of immunization and identification of high-risk groups, improvement in training of medical personnel and strategic planning of the Ministry of Health. seeking a proactive and collaborative approach to address the complex RSV situation in future winters. The Chilean Immunization Advisory Committee has already carried out an analysis and recommendation on a new prevention alternative. This working group will support any decision of the Ministry of Health in public policies that attempt a change in the paradigm of control of this disease for the health of the children of our country.

Absceso hepático en Cali, Colombia / Liver abscess in Cali, Colombia

INTRODUCCIÓN: El absceso hepático (AH) es el tipo mas común de abscesos viscerales. Se estima que el perfil epidemiológico de esta enfermedad ha cambiado con el aumento de la resistencia de los microorganismos y el uso de nuevos medicamentos. OBJETIVO: Describir las características demográficas y clínicas de los pacientes hospitalizados con diagnóstico de AH en un hospital universitario del suroccidente colombiano. MÉTODOS: Se realizó un estudio observacional retrospectivo, en la Fundación Valle del Lili, Cali, Colombia. Se incluyeron pacientes mayores de 18 años con diagnóstico de AH hospitalizados entre 2011-2020. RESULTADOS: Se incluyeron 182 pacientes. La mediana de edad fUe 56 años (rango intercuartílico, 45-67) y 62,1% fueron hombres. El microrganismo mas común fue Klebsiella pneumoniae (17,6%). La mayoría requirió drenaje percutáneo (58,2%). El 58,8% tuvo un absceso único y 54,4% fue manejado en cuidados intensivos. El 7,1% de los pacientes falleció. Al comparar los casos que fueron manejados en cuidados intensivos vs. aquellos que no lo fueron, hubo más hepatomegalia (28,3 vs. 11,0%, p = 0,004), derrame pleural derecho (48,5 vs. 28,1%, p = 0,010), cirugía (42,4 vs. 13,4%, p < 0,001), falla terapéutica (22,2 vs. 7,3%, p = 0,007) y muerte (12,1 vs. 1,2%, p = 0,005) en los atendidos en UCI. CONCLUSIÓN: Las Enterobacterales son la principal causa de AH en nuestra población. La mortalidad ha disminuido, pero la hospitalización en cuidados intensivos sigue siendo alta.

BACKGROUND: Liver abscess (LA) is the most common type of visceral abscess. It is estimated that the epidemiological profile of this disease has changed with the increase in resistance and the use of new drugs. AIM: To describe the demographic and clinical characteristics of hospitalized patients with a diagnosis of LA in a university hospital in the southwestern region of Colombia. METHODS: A. retrospective observational study was conducted at Fundación Valle del Lili, Cali, Colombia. Patients older than 18 years with a diagnosis of LA hospitalized between 2011-2020 were included. RESULTS: A total of 182 patients were included. The median age was 56 years (interquartile range, 45-67) and 62.1% were men. The most common microorganism was Klebsiella pneumoniae (17.6%). The majority required percutaneous drainage (58.2%). A 58.8% had a single abscess and 54.4% were treated in ICU. A 7.1% of the patients died. When comparing cases treated in the ICU vs. those who did not, there was more hepatomegaly (28.3 vs. 11.0%, p = 0.004), right pleural effusion (48.5 vs. 28.1%, p = 0.010), surgery (42.4 vs. 13.4%, p < 0.001), therapeutic failure (22.2 vs. 7.3%, p = 0.007) and death (12.1 vs. 1.2%, p = 0.005) in patients treated in ICU. CONCLUSION: Enterobacterales are the main cause of LA in our population. Mortality has decreased, but intensive care hospitalization remains high.

Improved all-cause mortality with left bundle branch area pacing compared to biventricular pacing in cardiac resynchronization therapy: a meta-analysis.

BACKGROUND: Left bundle branch area pacing (LBBAP) has emerged as a physiological alternative pacing strategy to biventricular pacing (BIVP) in cardiac resynchronization therapy (CRT). We aimed to assess the impact of LBBAP vs. BIVP on all-cause mortality and heart failure (HF)-related hospitalization in patients undergoing CRT. METHODS: Studies comparing LBBAP and BIVP for CRT in patients with HF with reduced left ventricular ejection fraction (LVEF) were included. The coprimary outcomes were all-cause mortality and HF-related hospitalization. Secondary outcomes included procedural and fluoroscopy time, change in QRS duration, and change in LVEF. RESULTS: Thirteen studies (12 observational and 1 RCT, n = 3239; LBBAP = 1338 and BIVP = 1901) with a mean follow-up duration of 25.8 months were included. Compared to BIVP, LBBAP was associated with a significant absolute risk reduction of 3.2% in all-cause mortality (9.3% vs 12.5%, RR 0.7, 95% CI 0.57-0.86, p < 0.001) and an 8.2% reduction in HF-related hospitalization (11.3% vs 19.5%, RR 0.6, 95% CI 0.5-0.71, p < 0.00001). LBBAP also resulted in reductions in procedural time (mean weighted difference- 23.2 min, 95% CI - 42.9 to - 3.6, p = 0.02) and fluoroscopy time (- 8.6 min, 95% CI - 12.5 to - 4.7, p < 0.001) as well as a significant reduction in QRS duration (mean weighted difference:- 25.3 ms, 95% CI - 30.9 to - 19.8, p < 0.00001) and a greater improvement in LVEF of 5.1% (95% CI 4.4-5.8, p < 0.001) compared to BIVP in the studies that reported these outcomes. CONCLUSION: In this meta-analysis, LBBAP was associated with a significant reduction in all-cause mortality as well as HF-related hospitalization when compared to BIVP. Additional data from large RCTs is warranted to corroborate these promising findings.

Intracardiac Echocardiography-guided Left Atrial Appendage Occlusion.

Left atrial appendage occlusion (LAAO) is a suitable alternative to oral anticoagulant therapy to prevent stroke in patients with AF. Most procedures are performed under transoesophageal echocardiography (TOE) guidance, which facilitates transseptal puncture, reduces the risk of procedurerelated complications and provides an additional method for device selection and real-time monitoring during device deployment. However, TOE has significant shortcomings, including the need for general anaesthesia/deep sedation as well as a significant risk of procedure-related adverse events. More recently, intracardiac echocardiography has been proposed as an alternative to TOE guidance during LAAO procedures. In this review, we summarise the available evidence as well as providing a step-by-step approach for intracardiac echocardiography-guided LAAO.

Las misiones médicas al Policlínico PAMS en Chincha: evolución del modelo de misión / The medical missions to the PAMS Polyclinic in Chincha: evolution of the mission's model

RESUMEN Presentamos la experiencia del Policlínico de la Peruvian American Medical Society (PAMS) en Chincha, en la ejecución de misiones médico-educativas en la región Chincha. El Policlínico PAMS presta atención médica general y especializada a la población de la zona, seis días a la semana. Además, recibe misiones médicas que vienen generalmente de los EE. UU. Desde 2011, se han recibido 43 misiones médicas. La composición y la naturaleza de las misiones han cambiado con el tiempo. Los primeros años se atraía a especialistas con el énfasis de traer equipos e insumos para mejorar la infraestructura del Policlínico. Ahora estamos limitados por la renuencia de voluntarios de venir al Perú en parte debido a que el gobierno americano considera que viajes al Perú son de alto riesgo. Esta limitación nos ha brindado la oportunidad de hacer misiones médicas juntamente con dos excelentes universidades peruanas. La experiencia ha sido positiva.

ABSTRACT We present the experience of the Polyclinic of the Peruvian American Medical Society (PAMS) in Chincha, in the execution of medical educational missions in the Chincha region. The PAMS Polyclinic provides general and specialized medical care to the population of the area, six days a week. In addition, the Polyclinic receives medical missions generally coming from the EE.UU. Since 2011, we have received 43 medical missions. The composition and nature of the missions have changed over time. The first years attracted specialists with the emphasis on bringing equipment and supplies to improve the infrastructure of the Polyclinic. We are now limited by the reluctance of volunteers to come to Peru in part because the U.S. government considers travel to Peru to be high-risk. This limitation has given us the opportunity to do medical missions together with two excellent Peruvian universities. This experience has been positive.

Usual interstitial pneumopathy in a patient with hypersensitivity pneumonitis and microscopic polyangiitis. Case report.

One of the most frequent diffuse interstitial lung diseases is hypersensitivity pneumonitis. It is related to exposure to diverse antigens, causing fibrosis in advanced stages, making the differential diagnosis with interstitial pulmonary fibrosis difficult as it overlaps with the usual interstitial pneumonia pattern. On the other hand, there are interstitial lung diseases associated with ANCA, such as microscopic polyangiitis, which is also related to the usual interstitial pneumonia pattern. We present the case of a 74-year-old male patient with chronic dyspnea, history of smoking and exposure to organic particles, in addition to a pattern suggestive of moderately severe restriction. The diagnosis was confirmed by histology of hypersensitivity pneumonitis by presenting granules, however, anti MPO and p-ANCA positivity was found, integrating the simultaneous diagnosis of microscopic polyangiitis. This is a case of difficult diagnosis since these pathologies have not been previously reported to coexist.

Chronic disease prevalence in a population with structural hemoglobin disorders undergoing diabetes diagnosis: A bayesian approach.

Background: Structural disorders of hemoglobin are a group of rare and fatal genetic diseases that disrupt the transport and exchange of oxygen in the blood, causing tissue damage and ultimately leading to chronic conditions. The hemoglobin (Hb) S variant predominantly impacts individuals of Afro-descendant heritage. A significant concentration of the Afro-descendant population in Colombia, notably 12.5 %, is found in the city of Cali. Previous research has identified this city's structural hemoglobin disorders prevalence rate of 3.78 %. The aim of this study was to determine the prevalence of HbC, HbS, HbF, and HbA2 variants within a population who underwent HbA1c testing, as well as the prevalence of chronic diseases among patients with these hemoglobin alterations, at a high-complexity hospital in the city of Cali from 2015 to 2019. Methods: A descriptive observational study was conducted, involving a study population that comprised patients with both suspected and monitored diagnoses of diabetes. The cohort was selected from a high-complexity hospital in Cali. A total of 15,608 patients were included in the analysis, all of whom underwent HbA1C measurement through capillary electrophoresis, which also offers an indirect diagnosis of certain structural disorders of hemoglobin. Bayesian methods were employed for frequency analysis. Results: Among the 15,608 patients assessed, 63.6 % (n = 9920) were women. The overall prevalence of structural hemoglobin disorders was 1.98 % (n = 287, 95 % CI = 1.77 %-2.21 %). The co-occurrence of diabetes and kidney disease emerged as the most prevalent combination of pathologies observed in individuals with HbC, for both men and women across various age groups: 18-42 (58.3 % and 50.0 % respectively), 43-55 (50.0 % for both), 56-65 (50.0 % and 37.5 % respectively), and >65 years (66.7 % and 57.1 % respectively). Conclusions: The observed prevalence of the studied variants exceeded 1 %, a threshold underscored by the World Health Organization (WHO) as epidemiologically significant. Among HbC and HbS-positive patients, the elevated prevalence of diabetes and kidney disease is a guiding factor in developing proactive prevention strategies.

Long chain capsaicin analogues synthetized by CALB-CLEAs show cytotoxicity on glioblastoma cell lines.

Glioblastoma is one of the most lethal tumors, displaying striking cellular heterogeneity and drug resistance. The prognosis of patients suffering from glioblastoma after 5 years is only 5%. In the present work, capsaicin analogues bearing modifications on the acyl chain with long-chain fatty acids showed promising anti-tumoral activity by its cytotoxicity on U-87 and U-138 glioblastoma multiforme cells. The capsaicin analogues were enzymatically synthetized with cross-linked enzyme aggregates of lipase B from Candida antarctica (CALB). The catalytic performance of recombinant CALB-CLEAs was compared to their immobilized form on a hydrophobic support. After 72 h of reaction, the synthesis of capsaicin analogues from linoleic acid, docosahexaenoic acid, and punicic acid achieved a maximum conversion of 69.7, 8.3 and 30.3% with CALB-CLEAs, respectively. Similar values were obtained with commercial CALB, with conversion yields of 58.3, 24.2 and 22% for capsaicin analogues from linoleic acid, DHA and punicic acid, respectively. Olvanil and dohevanil had a significant cytotoxic effect on both U-87 and U-138 glioblastoma cells. Irrespective of the immobilization form, CALB is an efficient biocatalyst for the synthesis of anti-tumoral capsaicin derivatives. KEY POINTS: • This is the first report concerning the enzymatic synthesis of capsaicin analogues from docosahexaenoic acid and punicic acid with CALB-CLEAs. • The viability U-87 and U-138 glioblastoma cells was significantly affected after incubation with olvanil and dohevanil. • Capsaicin analogues from fatty acids obtained by CALB-CLEAs are promising candidates for therapeutic use as cytotoxic agents in glioblastoma cancer cells.

Non-biofilm-forming Staphylococcus epidermidis planktonic cell supernatant induces alterations in osteoblast biological function.

Staphylococcal biofilms significantly contribute to prosthetic joint infection (PJI). However, 40% of S. epidermidis PJI isolates do not produce biofilms, which does not explain the role of biofilms in these cases. We studied whether the supernatant from planktonic S. epidermidis alters osteoblast function. Non-biofilm-forming S. epidermidis supernatants (PJI- clinical isolate, healthy skin isolate (HS), and ATCC12228 reference strain) and biofilm-forming supernatants (PJI+ clinical isolate, ATCC35984 reference strain, and Staphylococcus aureus USA300 reference strain) were included. Osteoblasts stimulated with supernatants from non-biofilm-forming isolates for 3, 7, and 14 days showed significantly reduced cellular DNA content compared with unstimulated osteoblasts, and apoptosis was induced in these osteoblasts. Similar results were obtained for biofilm-forming isolates, but with a greater reduction in DNA content and higher apoptosis. Alkaline phosphatase activity and mineralization were significantly reduced in osteoblasts treated with supernatants from non-biofilm-forming isolates compared to the control at the same time points. However, the supernatants from biofilm-forming isolates had a greater effect than those from non-biofilm-forming isolates. A significant decrease in the expression of ATF4, RUNX2, ALP, SPARC, and BGLAP, and a significant increase in RANK-L expression were observed in osteoblasts treated with both supernatants. These results demonstrate that the supernatants of the S. epidermidis isolate from the PJI- and HS (commensal) with a non-biofilm-forming phenotype alter the function of osteoblasts (apoptosis induction, failure of cell differentiation, activation of osteoblasts, and induction of bone resorption), similar to biofilm-forming isolates (PJI+, ATCC35984, and S. aureus USA300), suggesting that biofilm status contributes to impaired osteoblast function and that the planktonic state can do so independently of biofilm production.

"NASCI case of the month: left ventricular apical hypoplasia".

Left ventricular apical hypoplasia is a rare congenital condition. It can cause nonspecific symptoms and can be accompanied by cardiac conduction system alterations such as bundle branch block, atrial flutter (AF) or atrial fibrillation. The diagnosis mostly is made by imaging.

Impact of intracardiac echocardiography versus transesophageal echocardiography guidance on left atrial appendage occlusion procedures: A meta-analysis.

BACKGROUND: Intracardiac echocardiography (ICE) is increasingly used during left atrial appendage occlusion (LAAO) as an alternative to transesophageal echocardiography (TEE). The objective of this study is to evaluate the impact of ICE versus TEE guidance during LAAO on procedural characteristics and acute outcomes, as well the presence of peri-device leaks and residual septal defects during follow-up. METHODS: All studies comparing ICE-guided versus TEE-guided LAAO were identified. The primary outcomes were procedural efficacy and occurrence of procedure-related complications. Secondary outcomes included lab efficiency (defined as a reduction in in-room time), procedural time, fluoroscopy time, and presence of peri-device leaks and residual interatrial septal defects (IASD) during follow-up. RESULTS: Twelve studies (n = 5637) were included. There were no differences in procedural success (98.3% vs. 97.8%; OR 0.73, 95% CI 0.42-1.27, p = .27; I2 = 0%) or adverse events (4.5% vs. 4.4%; OR 0.81 95% CI 0.56-1.16, p = .25; I2 = 0%) between the ICE-guided and TEE-guided groups. ICE guidance reduced in in-room time (mean-weighted 28.6-min reduction in in-room time) without differences in procedural time or fluoroscopy time. There were no differences in peri-device leak (OR 0.93, 95% CI 0.68-1.27, p = 0.64); however, an increased prevalence of residual IASD was observed with ICE-guided versus TEE-guided LAAO (46.3% vs. 34.2%; OR 2.23, 95% CI 1.05-4.75, p = 0.04). CONCLUSION: ICE guidance is associated with similar procedural efficacy and safety, but could result in improved lab efficiency (as established by a significant reduction in in-room time). No differences in the rate of periprocedural leaks were found. A higher prevalence of residual interatrial septal defects was observed with ICE guidance.

Left Bundle Branch Pacing vs Left Ventricular Septal Pacing vs Biventricular Pacing for Cardiac Resynchronization Therapy.

BACKGROUND: Left bundle branch pacing (LBBP) and left ventricular septal pacing (LVSP) are considered to be acceptable as LBBAP strategies. Differences in clinical outcomes between LBBP and LVSP are yet to be determined. OBJECTIVES: The purpose of this study was to compare the outcomes of LBBP vs LVSP vs BIVP for CRT. METHODS: In this prospective multicenter observational study, LBBP was compared with LVSP and BIVP in patients undergoing CRT. The primary composite outcome was freedom from heart failure (HF)-related hospitalization and all-cause mortality. Secondary outcomes included individual components of the primary outcome, postprocedural NYHA functional class, and electrocardiographic and echocardiographic parameters. RESULTS: A total of 415 patients were included (LBBP: n = 141; LVSP: n = 31; BIVP: n = 243), with a median follow-up of 399 days (Q1-Q3: 249.5-554.8 days). Freedom from the primary composite outcomes was 76.6% in the LBBP group and 48.4% in the LVSP group (HR: 1.37; 95% CI: 1.143-1.649; P = 0.001), driven by a 31.4% absolute increase in freedom from HF-related hospitalizations (83% vs 51.6%; HR: 3.55; 95% CI: 1.856-6.791; P < 0.001) without differences in all-cause mortality. LBBP was also associated with a higher freedom from the primary composite outcome compared with BIVP (HR: 1.43; 95% CI: 1.175-1.730; P < 0.001), with no difference between LVSP and BIVP. CONCLUSIONS: In patients undergoing CRT, LBBP was associated with improved outcomes compared with LVSP and BIVP, while outcomes between BIVP and LVSP are similar.

Enhancement of Electricity Production in Microbial Fuel Cells Using a Biosurfactant-Producing Co-Culture.

Microbial fuel cells are bio-electrochemical devices that enable the conversion of chemical energy into bioelectricity. In this manuscript, the use of biosurfactants (Tween 80 and surfactin) and the effect of coculturing E. coli and L. plantarum were used to investigate the generation of bioelectricity coming from an H-type microbial fuel cell. In this setup, E. coli acts as an electron donor while L. plantarum acts as an in situ biosurfactant producer. It was observed that the use of exogenous surfactants enhanced electricity production compared to conventional E. coli cultures. The utilization of Tween 80 and surfactin increased the power generation from 204 µW m-2 to 506 µW m-2 and 577 µW m-2, respectively. Furthermore, co-culturing E. coli and L. plantarum also resulted in a higher power output compared to pure cultures (132.8% more when compared to using E. coli alone and 68.1% more when compared to using L. plantarum alone). Due to the presence of surfactants, the internal resistance of the cell was reduced. The experimental evidence collected here clearly indicates that the production of endogenous surfactants, as well as the addition of exogenous surfactants, will enhance MFC electricity production.

NADH-based kinetic model for acetone-butanol-ethanol production by Clostridium.

We present in this work a kinetic model of the acetone-butanol-ethanol (ABE) fermentation based on enzyme kinetics expressions. The model includes the effect of the co-substrate NADH as a modulating factor of cellular metabolism. The simulations obtained with the model showed an adequate fit to the experimental data reported by several authors, matching or improving the results observed with previous models. In addition, this model does not require artificial mathematical strategies such as on-off functions to achieve a satisfactory fit of the ABE fermentation dynamics. The parametric sensitivity allowed to identify the direct glucose → acetyl-CoA → butyryl-CoA pathway as being more significant for butanol production than the acid re-assimilation pathway. Likewise, model simulations showed that the increase in NADH, due to glucose concentration, favors butanol production and selectivity, finding a maximum selectivity of 3.6, at NADH concentrations above 55 mM and glucose concentration of 126 mM. The introduction of NADH in the model would allow its use for the analysis of electrofermentation processes with Clostridium, since the model establishes a basis for representing changes in the intracellular redox potential from extracellular variables.

Nucleotides as Bacterial Second Messengers.

In addition to comprising monomers of nucleic acids, nucleotides have signaling functions and act as second messengers in both prokaryotic and eukaryotic cells. The most common example is cyclic AMP (cAMP). Nucleotide signaling is a focus of great interest in bacteria. Cyclic di-AMP (c-di-AMP), cAMP, and cyclic di-GMP (c-di-GMP) participate in biological events such as bacterial growth, biofilm formation, sporulation, cell differentiation, motility, and virulence. Moreover, the cyclic-di-nucleotides (c-di-nucleotides) produced in pathogenic intracellular bacteria can affect eukaryotic host cells to allow for infection. On the other hand, non-cyclic nucleotide molecules pppGpp and ppGpp are alarmones involved in regulating the bacterial response to nutritional stress; they are also considered second messengers. These second messengers can potentially be used as therapeutic agents because of their immunological functions on eukaryotic cells. In this review, the role of c-di-nucleotides and cAMP as second messengers in different bacterial processes is addressed.

Trastornos psicóticos en Paraguay: ¿existen diferencias significativas entre zonas urbanas y rurales? / Psychotic disorders in Paraguay: Are there any significant differences between urban and rural areas?

Actualmente existe una tendencia mundial de desplazamiento de la población rural hacia áreas cada vez más urbanizadas. Existe evidencia que informa que el desarrollo de las enfermedades mentales tiene relación importante con factores tanto internos (por ejemplo, genéticos) y externos (el ambiente, entre otros). Con respecto a esto último, la manera en la que el entorno afecta a la salud mental es un objeto de estudio de interés global y se ha reportado que las áreas urbanas presentan mayores tasas de trastornos mentales comunes en comparación con las rurales. En el caso de la psicosis, por más de que el factor genético sea el más demostrado (y estudiado en los últimos años), el factor ambiental representando por el ambiente urbano ya ha sido analizado por investigadores a inicios del siglo 20. Desde allí, a lo largo de los años se obtuvo evidencia repetida que lo respalda como un factor de riesgo. Se ha encontrado que, además, existe relación con el grado de exposición, lo que hace pensar que la causa no solamente se limita a la transición del área rural al área urbana, sino que están involucrados factores sociales, económicos y medioambientales más profundos como la disparidad social, inseguridad, contaminación, entre otros 1. Ya en las últimas décadas del siglo 20, investigadores informaron de un aumento de la incidencia de esquizofrenia de 1,65 en hombres que vivían ciudades sobre sus contrapartes de origen rural. Años después, otros estudios han reportado esta variación en la incidencia de primeros episodios psicóticos a través del gradiente social urbano-rural, así como una relación entre el aumento de hospitalización por esquizofrenia con el grado de urbanización.

Terapia de remediación cognitiva en bulimia nerviosa: Un estudio de caso / Cognitive remediation therapy in bulimia nervosa: A case study

Resumen El objetivo de este estudio fue realizar una evaluación preliminar de la terapia de remediación cognitiva (TRE) en una paciente con bulimia nerviosa (BN). Bajo un diseño pre-post-tratamiento, la paciente (20 años de edad e índice de masa corporal [IMC] de 22.41) completó cuatro pruebas neuropsicológicas, tres medidas de síntomas de BN y dos de sintomatología psiquiátrica (depresión y ansiedad). Con base a las puntuaciones pre y post TRE fue calculado el cambio clínico objetivo (CCO). Los principales efectos neuropsicológicos se registraron en: flexibilidad de pensamiento, proceso visocontructivo, coherencia central y planificación (CCO = 0.39-0.99). También se identificaron cambios relevantes en las medidas de sintomatología psiquiátrica y de BN (CCO = 0.53-0.88), no así en el IMC. Este estudio suma evidencias respecto a la utilidad de la CRT en el tratamiento multidisciplinario, ya no solo de la anorexia nerviosa, sino que extiende su aplicabilidad a la BN.

Abstract The aim of this study was to perform a preliminary evaluation of cognitive remediation therapy (CRT) in a patient with bulimia nervosa (BN). The participant was 20 years old with a 22.41kg/m2 body mass index (BMI). Under a pre-post treatment design, the patient was administered four neuropsychological tests, three measures of BN symptoms and two of psychiatric symptomatology (depression and anxiety). Based on the pre and post CRT scores, the objective clinical change (OCC) was calculated. The main neuropsychological effects were observed in cognitive flexibility, visoconstructive processing (memory and central coherence) and working memory (OCC = 0,39-0,99). Relevant changes were also identified in the measures of psychiatric symptomatology and BN (OCC = 0,53-0,88), with no change in BMI. This study adds evidence regarding the usefulness of CRT in the multidisciplinary treatment not only of anorexia nervosa, but also extends its applicability to another eating disorder, BN.