Generation of immunocompetent somatic glioblastoma mouse models through in situ transformation of subventricular zone neural stem cells.

Disease-relevant in vivo tumor models are essential tools for both discovery and translational research. Here, we describe a highly genetically tractable technique for generating immunocompetent somatic glioblastoma (GBM) mouse models using piggyBac transposition and CRISPR-Cas9-mediated gene editing in wild-type mice. We describe steps to deliver plasmids into subventricular zone endogenous neural stem cells by injection and electroporation, leading to the development of adult tumors that closely recapitulate the histopathological, molecular, and cellular features of human GBM. For complete details on the use and execution of this protocol, please refer to Garcia-Diaz et al.1.

A successful method to restore seagrass habitats in coastal areas affected by consecutive natural events.

Background: Seagrass meadows, known for providing essential ecosystem services like supporting fishing, coastline protection from erosion, and acting as carbon sinks to mitigate climate change effects, are facing severe degradation. The current deteriorating state can be attributed to the combination of anthropogenic activities, biological factors (i.e., invasive species), and natural forces (i.e., hurricanes). Indeed, the global seagrass cover is diminishing at an alarming mean rate of 7% annually, jeopardizing the health of these vital ecosystems. However, in the Island Municipality of Culebra, Puerto Rico, losses are occurring at a faster pace. For instance, hurricanes have caused over 10% of cover seagrass losses, and the natural recovery of seagrasses across Culebra's coast has been slow due to the low growth rates of native seagrasses (Thalassia testudinum and Syringodium filiforme) and the invasion of the invasive species Halophila stipulacea. Restoration programs are, thus, necessary to revitalize the native seagrass communities and associated fauna while limiting the spread of the invasive species. Methods: Here, we present the results of a seagrass meadow restoration project carried out in Punta Melones (PTM), Culebra, Puerto Rico, in response to the impact of Hurricanes Irma and María during 2017. The restoration technique used was planting propagation units (PUs), each with an area of 900 cm2 of native seagrasses Thalassia testudinum and Syringodium filiforme, planted at a depth between 3.5 and 4.5 m. A total of 688 PUs were planted between August 2021 and August 2023, and a sub-sample of 88 PUs was monitored between August 2021 and April 2023. Results: PUs showed over 95% of the seagrass survived, with Hurricane Fiona causing most of the mortalities potentially due to PUs burial by sediment movement and uplifting by wave energy. The surface area of the planting units increased by approximately 200% (i.e., 2,459 cm2), while seagrass shoot density increased by 168% (i.e., 126 shoots by PU). Additionally, flowering and fruiting were observed in multiple planting units, indicating 1) that the action taken did not adversely affect the PUs units and 2) that the project was successful in revitalizing seagrass populations. The seagrass restoration project achieved remarkable success, primarily attributed to the substantial volume of each PUs. Likely this high volume played a crucial role in facilitating the connection among roots, shoots, and microfauna while providing a higher number of undamaged and active rhizome meristems and short shoots. These factors collectively contributed to the enhanced growth and survivorship of the PUs, ultimately leading to the favorable outcome observed in the seagrass restoration project.

Uneven demographic consequences of the 2022 disease outbreak for the sea urchin Diadema antillarum in Puerto Rico.

Pervasive epizootic events have had a significant impact on marine invertebrates throughout the Caribbean, leading to severe population declines and consequential ecological implications. One such event was the regional collapse of herbivory, partly caused by the Diadema antillarum mortality event in 1983-84, resulting in a trophic cascade and altering the structure of reef communities. Consequently, there was a notable decrease in coral recruitment and an increase in the coverage of macroalgae. Nearly four decades later, in early 2022, the Caribbean basin experienced another widespread mass mortality event, further reducing the populations of D. antillarum. To assess the effects of this recent mortality event on the current demographics of D. antillarum, we surveyed eight populations along the eastern, northeastern, northern, and northwestern coast of Puerto Rico from May to July 2022, estimating their population density, size distribution, and disease prevalence. Additionally, the study compared these population parameters with data from four sites previously surveyed in 2012 and 2017 to understand the impact of the recent mortality event. The survey conducted in 2022 showed varying population densities at the surveyed reefs. Some populations exhibited mean densities of nearly one individual per square meter, while others had extremely low or no living individuals per square meter. The four populations with the highest density showed no evidence of disease, whereas the four populations with the lowest D. antillarum densities exhibited moderate to high disease prevalence. However, when considering all sites, the estimated disease prevalence remained below 5%. Nevertheless, the comparison with data from 2012 and 2017 indicated that the recent mortality event had a negative impact on D. antillarum demographics at multiple sites, as the densities in 2022 were reduced by 60.19% compared to those from the previous years. However, it is still too early to determine the severity of this new mortality event compared to the 1983-84 mortality event. Therefore, it is imperative to continue monitoring these populations.

Criterios broncoscópicos, laboratoriales y anatomopatológicos de enfermedad de la vía aérea en pacientes diagnosticados con granulomatosis con poliangitis / Bronchoscopic, laboratory and anatomopathological criteria for airway disease in patients diagnosed with granulomatosis with polyangiitis

Introducción: los pacientes con granulomatosis con poliangitis (GPA) pueden presentar compromiso de la vía aérea superior (VAS) o inferior (VAI). Objetivos: describimos las manifestaciones endoscópicas de las vías respiratorias, los hallazgos histológicos y los anticuerpos anticitoplasma de neutrófilos (ANCA) en un grupo de pacientes con GPA. Métodos: estudio retrospectivo de historias clínicas de pacientes con GPA sometidos a broncoscopia entre 2012 y 2019. Se analizaron hallazgos de la vía aérea, biopsias y ANCA. Resultados: se incluyeron 40 pacientes, con una edad media de 46,92±17,61 años, predominantemente del sexo femenino (67,5%). Se observó afectación de la vía aérea en el 90% (n=36). El C-ANCA fue reactivo en el 63,9%, P-ANCA en el 25%, ANCA doblemente reactivo en el 8,33% y no reactivo en el 20%. Los hallazgos comunes en la vía aérea superior (VS) fueron sinusitis crónica (41,7%), destrucción del tabique nasal (16,7%); y en la vía aérea inferior (AI): estenosis traqueobronquial (38,9%), traqueobronquitis (25%). Los hallazgos más frecuentes de las biopsias broncoscópicas fueron proceso inflamatorio polimorfonuclear (61,9%) y necrosis geográfica (47,6%). Conclusión: la vía aérea está comprometida hasta en un 90% de los pacientes con GPA. ANCA no reactivos no descartan esta posibilidad. La sinusitis crónica y los procesos fibroestenóticos traqueobronquiales fueron los hallazgos endoscópicos más comunes. La vasculitis en biopsias se encontró en una minoría de casos.

Introduction: patients with granulomatosis with polyangiitis (GPA) may present upper airway (UA) and lower airway (LA) involvement. Objectives: we describe the endoscopic manifestations of the airways, histological findings from biopsied tissue and antineutrophilic cytoplasm antibody (ANCA) in a group of patients with GPA. Methods: retrospective study of medical records of patients with GPA undergoing bronchoscopy between 2012 and 2019. Airway findings, results of biopsies performed and ANCA results were analyzed. Results: 40 patients were included, with a mean age of 46.92±17.61 years and predominantly female (67.5%). Airway involvement was observed in 90% (n=36). The C-ANCA was reactive in 63.9%, P-ANCA in 25%, doubly reactive ANCA in 8.33% and non-reactive in 20%. The findings in upper airway (UA) were: chronic sinusitis (41.7%), destruction of the nasal septum (16.7%); and in lower airway (LA) were: tracheobronchial stenosis (38.9%) and tracheobronchitis (25%). The pathological findings most common of bronchoscopic biopsies were: polymorphonuclear inflammatory process (61.9%) and geographic necrosis (47.6%). Conclusion: the airway is involved in up to 90% of patients with GPA. Non-reactive ANCA does not rule out this possibility. Chronic sinusitis and tracheobronchial fibrostenotic processes were the most common endoscopic findings. Vasculitis in biopsies was found in a minority of cases.

Large Animal Models of Cardiovascular Disease: From Training to Translation.

ARTICLES DISCUSSED: Blanco-Blázquez, V. et al. Swine models of aneurysmal diseases for training and research. Journal of Visualized Experiments. (181), e63616 (2022). Constantin, I., Tabaran, A. F. Dissection techniques and histological sampling of the heart in large animal models for cardiovascular diseases. Journal of Visualized Experiments. (184), e63809 (2022). Hao, Y. et al. Transcatheter pulmonary valve replacement from autologous pericardium with a self-expandable nitinol stent in an adult sheep model. Journal of Visualized Experiments. (184), e63661 (2022). Martínez-Falguera, D. et al. Myocardial infarction by percutaneous embolization coil deployment in a swine model. Journal of Visualized Experiments. (177), e63172 (2021). Tubeeckx, M. R. L. et al. Sterile pericarditis in aachener minipigs as a model for atrial myopathy and atrial fibrillation. Journal of Visualized Experiments. (175), e63094 (2021).

The "Breast-4Y" web app for breast cancer prevention at young age: Development, evaluation, and validation.

Background: Improving knowledge of risk factors, signs and symptoms positively influence an individual's intention to acquire healthy lifestyle behaviors to prevent breast cancer, to identify breast cancer risk early and seek health advice early. The aim of the present study was to develop and to assess the usability and quality of a web-app (Breast-4Y) designed specifically for younger women to improve their knowledge about breast cancer risk factors and symptoms as well as protective behaviors to reduce their risk. Methods: The development of the Breast-4Y web-app, based on Health Belief Model and the Behaviour Change Wheel, comprised four steps: i) analysis of scientific literature regarding breast cancer risk factors, symptoms and preventive lifestyle behaviors; ii) design of web-app; iii) content review by experts; iv) quality and usability assessment by the end-users (n = 20). Web-app usability was evaluated using the Spanish version of the System Usability Scale for the Assessment of Electronic Tools and the quality using the Spanish version of uMARS. Results: The contents were rated 4.25 or above, indicating high content quality. The mean usability score was 84.9 (SD 12.4), the mean rating for objective quality and subjective quality dimensions mean were 4.2 (SD 0.4) and 3.4 (0.777) respectively, indicating excellent usability and quality. Positive associations (p < .05) were observed between numbers of app used and attitudes to change (r = 0.479), and intention to change (r = 0.539). Strong positive associations (p < .001) were also observed between usability satisfaction and attitudes to change (r = 0.584), intention to change (r = 0.656), and help-seeking (r = 0.656). Conclusions: This study provided evidence that Breast-4Y has adequate contents, high quality, and usability. Breast-4Y can be tested in pragmatic trials to assess their effectiveness to reduce the risk of breast cancer, raise women's awareness of breast cancer risk factors, increase women's knowledge of breast cancer symptoms, and adopt protective lifestyle behaviors.

Relación entre la luna llena y la incidencia en partos prematuros vaginales en un hospital nivel III de Lima, Perú / Relationship between the full moon and the incidence of premature vaginal births in a level III hospital in Lima, Peru

Objetivo. Determinar la asociación entre la luna llena y la incidencia de partos prematuros vaginales entre mujeres con parto vaginal de un hospital de tercer nivel de Lima, Perú. Material y método. Se realizó un estudio transversal analítico de base secundaria del Certificado de Nacido Vivo (CNV) de Perú. Se estudiaron a todos los recién nacidos del Instituto Nacional Materno Perinatal entre los años 2013 a 2021. La duración de la fase de luna llena se determinó a través de lenguaje de programación con Python 3.6 y el análisis de la incidencia de prematuridad con el paquete estadístico STATA v15. Resultados. Se seleccionaron 90 653 recién nacidos del CNV de los cuales 11563 (12.75%) participantes nacieron durante los días de luna llena y 79089 (87.25%) durante las otras fases. Se observó una mayor incidencia de partos prematuros vaginales durante la fase de luna llena en comparación con otras fases (p<0.01). El análisis multivariado encontró que la luna llena tenía un 1.17% más de valor promedio de incidencia de partos prematuros vaginales ajustado por año en comparación con las demás fases (IC 95% 1.050 - 1.292, p<0.01). Conclusiones. Se encontró una mayor incidencia de partos prematuros vaginales durante la fase de luna llena en la población estudiada. Se deben tomar con cuidado estos resultados debido a que en el análisis se incluyeron los partos inducidos.

Glioblastoma cell fate is differentially regulated by the microenvironments of the tumor bulk and infiltrative margin.

Glioblastoma (GBM) recurrence originates from invasive margin cells that escape surgical debulking, but to what extent these cells resemble their bulk counterparts remains unclear. Here, we generated three immunocompetent somatic GBM mouse models, driven by subtype-associated mutations, to compare matched bulk and margin cells. We find that, regardless of mutations, tumors converge on common sets of neural-like cellular states. However, bulk and margin have distinct biology. Injury-like programs associated with immune infiltration dominate in the bulk, leading to the generation of lowly proliferative injured neural progenitor-like cells (iNPCs). iNPCs account for a significant proportion of dormant GBM cells and are induced by interferon signaling within T cell niches. In contrast, developmental-like trajectories are favored within the immune-cold margin microenvironment resulting in differentiation toward invasive astrocyte-like cells. These findings suggest that the regional tumor microenvironment dominantly controls GBM cell fate and biological vulnerabilities identified in the bulk may not extend to the margin residuum.

Ultrasound Assessment of Skin Tumors Local Recurrence.

Skin cancer may recur at or around the surgical site despite wide excisions. Prompt clinical and sonographic detection of local recurrence is important since subjects with relapsing melanomas or nonmelanoma malignancies can be managed efficaciously, with a relevant impact on morbidity and survival. Ultrasound is being employed with increasing frequency in the assessment of skin tumors, but most of the published articles relate to initial pretherapeutic diagnosis and staging. This review aims to offer an illustrated guide to the sonographic evaluation of locally recurring skin cancer. We introduce the topic, then we provide some sonographic tips for patient follow-up, then we describe the ultrasound findings in case of local recurrence, illustrating the main mimickers, and finally, we mention the role of ultrasound in guiding diagnostic and therapeutic percutaneous procedures.

Personalized tissue-engineered veins - long term safety, functionality and cellular transcriptome analysis in large animals.

Tissue engineering is a promising methodology to produce advanced therapy medicinal products (ATMPs). We have developed personalized tissue engineered veins (P-TEV) as an alternative to autologous or synthetic vascular grafts utilized in reconstructive vein surgery. Our hypothesis is that individualization through reconditioning of a decellularized allogenic graft with autologous blood will prime the tissue for efficient recellularization, protect the graft from thrombosis, and decrease the risk of rejection. In this study, P-TEVs were transplanted to vena cava in pig, and the analysis of three veins after six months, six veins after 12 months and one vein after 14 months showed that all P-TEVs were fully patent, and the tissue was well recellularized and revascularized. To confirm that the ATMP product had the expected characteristics one year after transplantation, gene expression profiling of cells from P-TEV and native vena cava were analyzed and compared by qPCR and sequencing. The qPCR and bioinformatics analysis confirmed that the cells from the P-TEV were highly similar to the native cells, and we therefore conclude that P-TEV is functional and safe in large animals and have high potential for use as a clinical transplant graft.

Diet suppresses glioblastoma initiation in mice by maintaining quiescence of mutation-bearing neural stem cells.

Glioblastoma is thought to originate from neural stem cells (NSCs) of the subventricular zone that acquire genetic alterations. In the adult brain, NSCs are largely quiescent, suggesting that deregulation of quiescence maintenance may be a prerequisite for tumor initiation. Although inactivation of the tumor suppressor p53 is a frequent event in gliomagenesis, whether or how it affects quiescent NSCs (qNSCs) remains unclear. Here, we show that p53 maintains quiescence by inducing fatty-acid oxidation (FAO) and that acute p53 deletion in qNSCs results in their premature activation to a proliferative state. Mechanistically, this occurs through direct transcriptional induction of PPARGC1a, which in turn activates PPARα to upregulate FAO genes. Dietary supplementation with fish oil containing omega-3 fatty acids, natural PPARα ligands, fully restores quiescence of p53-deficient NSCs and delays tumor initiation in a glioblastoma mouse model. Thus, diet can silence glioblastoma driver mutations, with important implications for cancer prevention.

Transcriptome Profile Reveals Differences between Remote and Ischemic Myocardium after Acute Myocardial Infarction in a Swine Model.

Acute myocardial infarction (AMI) is the consequence of an acute interruption of myocardial blood flow delimiting an area with ischemic necrosis. The loss of cardiomyocytes initiates cardiac remodeling in the myocardium, leading to molecular changes in an attempt to recover myocardial function. The purpose of this study was to unravel the differences in the molecular profile between ischemic and remote myocardium after AMI in an experimental model. To mimic human myocardial infarction, healthy pigs were subjected to occlusion of the mid-left anterior descending coronary artery, and myocardial tissue was collected from ischemic and remote zones for omics techniques. Comparative transcriptome analysis of both areas was accurately validated by proteomic analysis, resulting in mitochondrion-related biological processes being the most impaired mechanisms in the infarcted area. Moreover, Immune system process-related genes were up-regulated in the remote tissue, mainly due to the increase of neutrophil migration in this area. These results provide valuable information regarding differentially expressed genes and their biological functions between ischemic and remote myocardium after AMI, which could be useful for establishing therapeutic targets for the development of new treatments.

Intracoronary Administration of Microencapsulated HGF in a Reperfused Myocardial Infarction Swine Model.

Therapy microencapsulation allows minimally invasive, safe, and effective administration. Hepatocyte growth factor (HGF) has angiogenic, anti-inflammatory, anti-apoptotic, and anti-fibrotic properties. Our objective was to evaluate the cardiac safety and effectiveness of intracoronary (IC) administration of HGF-loaded extended release microspheres in an acute myocardial infarction (AMI) swine model. An IC infusion of 5 × 106 HGF-loaded microspheres (MS+HGF, n = 7), 5 × 106 placebo microspheres (MS, n = 7), or saline (SAL, n = 7) was performed two days after AMI. TIMI flow and Troponin I (TnI) values were assessed pre- and post-treatment. Cardiac function was evaluated with magnetic resonance imaging (cMR) before injection and at 10 weeks. Plasma cytokines were determined to evaluate the inflammatory profile and hearts were subjected to histopathological evaluation. Post-treatment coronary flow was impaired in five animals (MS+HGF and MS group) without significant increases in TnI. One animal (MS group) died during treatment. There were no significant differences between groups in cMR parameters at any time (p > 0.05). No statistically significant changes were found between groups neither in cytokines nor in histological analyses. The IC administration of 5 × 106 HGF-loaded-microspheres 48 h post-AMI did not improve cardiac function, nor did it decrease inflammation or cardiac fibrosis in this experimental setting.

Ester Reduction with H2 on Bifunctional Metal-Acid Catalysts: Implications of Metal Identity on Rates and Selectivities.

Esters reduce to form ethers and alcohols on contact with metal nanoparticles supported on Brønsted acidic faujasite (M-FAU) that cleave C-O bonds by hydrogenation and hydrogenolysis pathways. Rates and selectivities for each pathway depend on the metal identity (M=Co, Ni, Cu, Ru, Rh, Pd, and Pt). Pt-FAU gives propyl acetate consumption rates up to 100 times greater than other M-FAU catalysts and provides an ethyl propyl ether selectivity of 34 %. Measured formation rates, kinetic isotope effects, and site titrations suggest that ester reduction involves a bifunctional mechanism that implicates the stepwise addition of H* atoms to the carbonyl to form hemiacetals on the metal sites, followed by hemiacetal diffusion to a nearby Brønsted acid site to dehydrate to ethers or decompose to alcohol and aldehyde. The rates of reduction of propyl acetate appear to be determined by the H* addition to the carbonyl and by the C-O cleavage of hemiacetal.

Evolution of SARS-CoV-2 during the first year of the COVID-19 pandemic in Northwestern Argentina.

Studies about the evolution of SARS-CoV-2 lineages in different backgrounds such as naive populations are still scarce, especially from South America. This work aimed to study the introduction and diversification pattern of SARS-CoV-2 during the first year of the COVID-19 pandemic in the Northwestern Argentina (NWA) region and to analyze the evolutionary dynamics of the main lineages found. In this study, we analyzed a total of 260 SARS-CoV-2 whole-genome sequences from Argentina, belonging to the Provinces of Jujuy, Salta, and Tucumán, from March 31st, 2020, to May 22nd, 2021, which covered the full first wave and the early second wave of the COVID-19 pandemic in Argentina. In the first wave, eight lineages were identified: B.1.499 (76.9%), followed by N.5 (10.2%), B.1.1.274 (3.7%), B.1.1.348 (3.7%), B.1 (2.8%), B.1.600 (0.9%), B.1.1.33 (0.9%) and N.3 (0.9%). During the early second wave, the first-wave lineages were displaced by the introduction of variants of concern (VOC) (Alpha, Gamma), or variants of interest (VOI) (Lambda, Zeta, Epsilon) and other lineages with more limited distribution. Phylodynamic analyses of the B.1.499 and N.5, the two most prevalent lineages in the NWA, revealed that the rate of evolution of lineage N.5 (7.9 × 10-4 substitutions per site per year, s/s/y) was a ∼40% faster than that of lineage B.1.499 (5.6 × 10-4 s/s/y), although both are in the same order of magnitude than other non-VOC lineages. No mutations associated with a biological characteristic of importance were observed as signatures markers of the phylogenetic groups established in Northwestern Argentina, however, single sequences in non-VOC lineages did present mutations of biological importance or associated with VOCs as sporadic events, showing that many of these mutations could emerge from circulation in the general population. This study contributed to the knowledge about the evolution of SARS-CoV-2 in a pre-vaccination and without post-exposure immunization period.

Carcinoma epidermoide sarcomatoso metastásico a la placenta: un reporte de caso / Metastatic sarcomatosus squamous carcinoma to the placenta: a case report

Resumen ANTECEDENTES: El cáncer epidermoide cutáneo de tipo sarcomatoide es una neoplasia rara, de bajo riesgo de malignidad, con menos del 2% de riesgo de metástasis. Su comportamiento agresivo es inusual y casi siempre asociado con factores que favorecen su malignidad. La metástasis a la placenta es también excepcional: hasta la actualidad solo se han reportado 61 casos. CASO CLÍNICO: Paciente de 35 años con antecedentes de dos embarazos, en curso de las 33 semanas de gestación, carcinoma epidermoide infiltrante en la pierna izquierda, con amputación supracondílea y metástasis pulmonar. Ingresó a urgencias por dificultad respiratoria, sin trabajo de parto, taquicárdica y taquipneica. Se decidió la cesárea con obtención de nacido vivo, de sexo femenino, 1860 g, sin complicaciones. Luego de la intervención, la paciente fue trasladada a una institución especializada en atención oncológica, donde falleció a las 24 horas. La recién nacida se dio de alta sin complicaciones y sin manifestaciones oncológicas o de otro tipo hasta el año de nacida. CONCLUSIONES: Luego de una búsqueda exhaustiva en la bibliografía los autores consideran que el caso aquí comunicado es el primero en Perú de cáncer epidermoide cutáneo de tipo sarcomatoide con metástasis a la placenta.

Abstract BACKGROUND: Sarcomatoid cutaneous epidermoid cancer is a rare neoplasm, with a low risk of malignancy and less than 2% risk of metastasis. Its aggressive behavior is unusual and almost always associated with factors favoring its malignancy. Placental metastasis is also exceptional: only 61 cases have been reported to date. CLINICAL CASE: 35-year-old female patient, with a history of two pregnancies, in 33 weeks of gestation, infiltrating squamous cell carcinoma of the left leg, with supracondylar amputation and pulmonary metastasis. She was admitted to the emergency room for respiratory distress, without labor, tachycardic and tachypneic. It was decided to perform a cesarean section with live birth, female, 1860 g, without complications. After the intervention, the patient was transferred to an institution specialized in oncologic care, where she died 24 hours later. The newborn was discharged without complications and without oncologic or other manifestations up to one year of age. CONCLUSIONS: After an exhaustive search of the literature, the authors consider the case reported here to be the first case of sarcomatoid epidermoid skin cancer with metastasis to the placenta.

Effects of Cardiac Stem Cell on Postinfarction Arrhythmogenic Substrate.

Clinical data suggest that cardiosphere-derived cells (CDCs) could modify post-infarction scar and ventricular remodeling and reduce the incidence of ventricular tachycardia (VT). This paper assesses the effect of CDCs on VT substrate in a pig model of postinfarction monomorphic VT. We studied the effect of CDCs on the electrophysiological properties and histological structure of dense scar and heterogeneous tissue (HT). Optical mapping and histological evaluation were performed 16 weeks after the induction of a myocardial infarction by transient occlusion of the left anterior descending (LAD) artery in 21 pigs. Four weeks after LAD occlusion, pigs were randomized to receive intracoronary plus trans-myocardial CDCs (IC+TM group, n: 10) or to a control group. Optical mapping (OM) showed an action potential duration (APD) gradient between HT and normal tissue in both groups. CDCs increased conduction velocity (53 ± 5 vs. 45 ± 6 cm/s, p < 0.01), prolonged APD (280 ± 30 ms vs. 220 ± 40 ms, p < 0.01) and decreased APD dispersion in the HT. During OM, a VT was induced in one and seven of the IC+TM and control hearts (p = 0.03), respectively; five of these VTs had their critical isthmus located in intra-scar HT found adjacent to the coronary arteries. Histological evaluation of HT revealed less fibrosis (p < 0.01), lower density of myofibroblasts (p = 0.001), and higher density of connexin-43 in the IC+TM group. Scar and left ventricular volumes did not show differences between groups. Allogeneic CDCs early after myocardial infarction can modify the structure and electrophysiology of post-infarction scar. These findings pave the way for novel therapeutic properties of CDCs.

Caracterización de un Consorcio Microbiano Metanogénico de una Mina de Carbón en la Cuenca de Bogotá / Characterization of a Methanogenic Microbial Consortium from a Coal Mine in Bogotá Basin

RESUMEN En el trabajo se estudió un consorcio microbiano metanogénico de una mina de carbón de la cuenca de Bogotá en Colombia. Se establecieron cultivos de enriquecimiento de carbón ex situ para el crecimiento y la producción de gas de novo. El gas biogénico producido por los cultivos se analizó mediante cromatografía de gases con detectores de ionización de llama y conductividad térmica. Los cultivos se utilizaron para aislar estirpes microbianas y para generar bibliotecas del gene 16S rARN empleando de cebadores de bacteria y de arquea. El análisis de cromatografía de gases mostró producción de metano a 37 oC, pero no a 60 oC, donde el CO2 fue el componente principal del gas biogénico. El análisis de la secuencia del gen 16S rARN de estirpes microbianos y de las bibliotecas de clones, estableció que el consorcio microbiano metanogénico estuvo formado por especies de bacterias de los géneros Bacillus y Gracilibacter más la arquea del género Methanothermobacter. El consorcio microbiano metanogénico identificado es potencialmente responsable de la generación de gas biogénico en la mina de carbón La Ciscuda. Los resultados sugirieron que los metanógenos de este consorcio producían metano por vía hidrogenotrófica o de reducción de CO2.

ABSTRACT The work studied the methanogenic microbial consortium in a coal mine from the Bogotá basin in Colombia. Ex situ coal-enrichment cultures were established for in vitro growth and de novo gas production. Biogenic gas produced by cultures was analyzed by gas chromatography using thermal conductivity and flame ionization detectors. Cultures were used to isolate microbial specimens and to generate 16S rRNA gene libraries employing bacterial and archaeal primer sets. The gas chromatographic analysis showed methane production at 37 oC, but not at 60 oC, where CO2 was the major component of the biogenic gas. 16S rRNA gene sequence analysis of microbial isolates and clone libraries established that the methanogenic microbial consortium was formed by bacteria species from Bacillus and Gracilibacter genera plus archaea from the Methanothermobacter genus. This meth-anogenic microbial consortium was potentially responsible for biogenic gas generation in La Ciscuda coal mine. The results suggested that these methanogens produced methane by hydrogenotrophic or CO2 reduction pathways.