Ultrastructural differences between synovial sarcoma and solitary fibrous tumor: comparative study in adult patients from the National Cancer Institute of Mexico.

Synovial sarcoma (SS) and solitary fibrous tumor (SFT) are entities with considerable morphological and immunohistochemical similarities that sometimes show a non-confirmatory profile (TLE1 negative, CD34 and focal or negative STAT6 and lack of specific fusion IHC markers), in which the utility ultrastructure is unknown. A cross-sectional, retrospective, analytical, nonexperimental study was carried out by the Department of Pathology of the National Cancer Institute of Mexico (INCan) e from January 1, 2009 to December 31, 2018. With 17 SFT cases with diffuse or focal CD34 and STAT6 positivity and 18 cases of SS with positive FISH molecular test t(X:18) breakapart were studied by electron microscopy of fresh glutaraldehyde fixed or paraffin-embedded tissue. The ultrastructural findings with a significant difference present in the SS were tandem tight junctions, desmosomes and abundance of dilated rough endoplasmic reticulum (RER) cisternae (p < 0.001, 0.003, and 0.001, respectively); while in the (SFT) the presence of abundant glycogen, basal lamina, long and slender cytoplasmic processes, pinocytic vesicles, hemidesmosomes, and/or dense plaques, collagen skein, and microvilli-like buds (p = 0.028, 0.005, and <0.001 for the last five). We then infer that the five distinctive markers of the SFT are the collagen skeins intermingled with cellular processes in a shape of "squid can," and the pinocytic vesicles as they were not observed in any case of SS. Conversely, tandem junctions were not found in any SFT case. Although the presence of multivesicular buds in the SFT was not significant, it had not been previously described.

Myxoinflammatory fibroblastic sarcoma: ultrastructural study of 7 cases.

Since first described, several studies about Myxoinflammatory fibroblastic sarcomas (MIFS) have been published stating the clinicopathological, morphological and immunohistochemical features. However, the ultrastructural findings of these MIFS are limited. Thus, the objective of the present paper is to describe the ultrastructural characteristics of these type of tumors by utilizing tissue that was embedded in paraffin and submitted for immunohistochemistry.The tissue of seven different cases was obtained for ultrastructural study with automatized staining devices, that were later observed by using transmission electron microscopy. Histologically all cases displayed conventional structures of Myxoinflammatory fibroblastic sarcoma (Reed-Sternberg like cells, pseudolipoblasts and emperipolesis). Conversely, two of them exhibited high-grade components, one rich in osteoclastic type giant cells and hypercellular areas, and another one rich in inflammation (Hodgkin-like).After immunohistochemistry, all the samples revealed positivity for CD68 with six cases CD163 and five being positive to CD34, Cyclin-D1, and D2-40. Ultrastructural findings indicated rough endoplasmic reticulum with dilatation of the cisterns that indented the nuclei ("soccer ball" cells), abundant lysosomes, phagolysosomes, and intermediate filaments evidencing this entity as a morphologic continuum that exhibited modified fibroblastic phenotype and variable proportion of macrophagic differentiation.

A Novel Lipase from Streptomyces exfoliatus DSMZ 41693 for Biotechnological Applications.

Genome mining of Streptomyces exfoliatus DSMZ 41693 has allowed us to identify four different lipase-encoding sequences, and one of them (SeLipC) has been successfully cloned and extracellularly expressed using Rhodococcus sp. T104 as a host. SeLipC was purified by one-step hydrophobic interaction chromatography. The enzyme is a monomeric protein of 27.6 kDa, which belongs to subfamily I.7 of lipolytic enzymes according to its phylogenetic analysis and biochemical characterization. The purified enzyme shows the highest activity at 60 °C and an optimum pH of 8.5, whereas thermal stability is significantly improved when protein concentration is increased, as confirmed by thermal deactivation kinetics, circular dichroism, and differential scanning calorimetry. Enzyme hydrolytic activity using p-nitrophenyl palmitate (pNPP) as substrate can be modulated by different water-miscible organic cosolvents, detergents, and metal ions. Likewise, kinetic parameters for pNPP are: KM = 49.6 µM, kcat = 57 s-1, and kcat/KM = 1.15 × 106 s-1·M-1. SeLipC is also able to hydrolyze olive oil and degrade several polyester-type polymers such as poly(butylene succinate) (PBS), poly(butylene succinate)-co-(butylene adipate) (PBSA), and poly(ε-caprolactone) (PCL). Moreover, SeLipC can catalyze the synthesis of different sugar fatty acid esters by transesterification using vinyl laurate as an acyl donor, demonstrating its interest in different biotechnological applications.

Improving genome-wide mapping of nucleosomes in Trypanosome cruzi.

In Trypanosoma cruzi DNA is packaged into chromatin by octamers of histone proteins that form nucleosomes. Transcription of protein coding genes in trypanosomes is constitutive producing polycistronic units and gene expression is primarily regulated post-transcriptionally. However, chromatin organization influences DNA dependent processes. Hence, determining nucleosome position is of uppermost importance to understand the peculiarities found in trypanosomes. To map nucleosomes genome-wide in several organisms, digestion of chromatin with micrococcal nuclease followed by deep sequencing has been applied. Nonetheless, the special requirements for cell manipulation and the uniqueness of the chromatin organization in trypanosomes entails a customized analytical approach. In this work, we adjusted this broadly used method to the hybrid reference strain, CL Brener. Particularly, we implemented an exhaustive and thorough computational workflow to overcome the difficulties imposed by this complex genome. We tested the performance of two aligners, Bowtie2 and HISAT2, and discuss their advantages and caveats. Specifically, we highlight the relevance of using the whole genome as a reference instead of the commonly used Esmeraldo-like haplotype to avoid spurious alignments. Additionally, we show that using the whole genome refines the average nucleosome representation, but also the quality of mapping for every region represented. Moreover, we show that the average nucleosome organization around trans-splicing acceptor site described before, is not just an average since the same chromatin pattern is detected for most of the represented regions. In addition, we extended the study to a non-hybrid strain applying the experimental and analytical approach to Sylvio-X10 strain. Furthermore, we provide a source code for the construction of 2D plots and heatmaps which are easy to adapt to any T. cruzi strain.

Análisis de la incidencia de pubertad precoz central tratada con análogos de hormona liberadora de gonadotrofina. Impacto de la pandemia por COVID-19 / Analysis of the incidence of central precocious puberty treated with gonadotropin-releasing hormone analogs. Impact of the COVID-19 pandemic

Introducción. Desde inicios de la pandemia por coronavirus 2019 (COVID-19), fue comunicado en varios países un incremento de las consultas de niñas con pubertad precoz central idiopática (PPCI), sin que contáramos con datos argentinos. Este aumento estaría vinculado con los cambios en el estilo de vida y los niveles de estrés resultantes del aislamiento que afectó particularmente a la población infantil. Objetivos. 1) Describir la evolución de la incidencia de PPCI con requerimiento de inhibición del eje hipotálamo-hipófiso-gonadal (EHHG) en niñas entre 2010 y 2021 en una cohorte del Área Metropolitana de Buenos Aires. 2) Comparar las características de las niñas, con dicho diagnóstico realizado durante la pandemia, con las de un grupo control. Métodos. Serie de tiempo interrumpida y estudio de casos y controles. Resultados. La incidencia anual fue estable entre 2010 y 2017. Desde 2017 hubo un ascenso anual que promedió el 59,9 % (IC95 % 18,6-115,5) y pareciera haberse acelerado durante la pandemia. Constatamos asociación entre haber desarrollado PPCI y haber requerido tratamiento inhibitorio entre el 01 de junio de 2020 y el 31 de mayo de 2021, y dos variables: edad de menarca materna (OR 0,46; IC95 % 0,28-0,77) y antecedente familiar de PPCI (OR 4,42; IC95 % 1,16-16,86). Conclusión. Evidenciamos desde 2017 un aumento significativo en la incidencia de PPCI con requerimiento de inhibición del EHHG. El incremento en la exposición a diversos desencadenantes ambientales durante la pandemia por COVID-19 podría haber ejercido mayor influencia en las niñas con alguna predisposición genética.

Introduction. Since the onset of the coronavirus disease 2019 (COVID-19) pandemic, consultations of girls with idiopathic central precocious puberty (ICPP) increased in several countries, but there were no data from Argentina. This increase may be related to changes in lifestyle and stress levels resulting from the lockdown, which particularly affected the child population. Objectives. 1) To describe the progression of the incidence of ICPP requiring inhibition of the hypothalamic- pituitary-gonadal (HPG) axis in girls between 2010 and 2021 in a cohort from the Metropolitan Area of Buenos Aires. 2) To compare the characteristics of girls diagnosed with ICPP during the pandemic with those of a control group. Methods. Interrupted time-series and case-control study. Results. The annual incidence remained stable between 2010 and 2017. Since 2017, it increased to an average of 59.9% (95% CI: 18.6­115.5) and appears to have accelerated during the pandemic. We found an association between ICPP and requiring inhibitory treatment between June 1 st, 2020 andMay 31 st, 2021 and 2 variables: maternal age at menarche (OR: 0.46, 95% CI: 0.28­0.77) and family history of ICPP (OR: 4.42, 95% CI: 1.16­16.86). Conclusion. We evidenced a significant increase in the incidence of ICPP with requirement of HPG axis inhibition since 2017. Increased exposure to various environmental triggers during the COVID-19 pandemic may have had a greater influence in girls with some genetic predisposition.

Analysis of the incidence of central precocious puberty treated with gonadotropin-releasing hormone analogs. Impact of the COVID-19 pandemic. / Análisis de la incidencia de pubertad precoz central tratada con análogos de hormona liberadora de gonadotrofina. Impacto de la pandemia por COVID-19.

Introduction. Since the onset of the coronavirus disease 2019 (COVID-19) pandemic, consultations of girls with idiopathic central precocious puberty (ICPP) increased in several countries, but there were no data from Argentina. This increase may be related to changes in lifestyle and stress levels resulting from the lockdown, which particularly affected the child population. Objectives. 1) To describe the progression of the incidence of ICPP requiring inhibition of the hypothalamic-pituitary-gonadal (HPG) axis in girls between 2010 and 2021 in a cohort from the Metropolitan Area of Buenos Aires. 2) To compare the characteristics of girls diagnosed with ICPP during the pandemic with those of a control group. Methods. Interrupted time-series and case-control study. Results. The annual incidence remained stable between 2010 and 2017. Since 2017, it increased to an average of 59.9% (95% CI: 18.6-115.5) and appears to have accelerated during the pandemic. We found an association between ICPP and requiring inhibitory treatment between June 1st, 2020 and May 31st, 2021 and 2 variables: maternal age at menarche (OR: 0.46, 95% CI: 0.28-0.77) and family history of ICPP (OR: 4.42, 95% CI: 1.16-16.86). Conclusion. We evidenced a significant increase in the incidence of ICPP with requirement of HPG axis inhibition since 2017. Increased exposure to various environmental triggers during the COVID-19 pandemic may have had a greater influence in girls with some genetic predisposition.

Introducción. Desde inicios de la pandemia por coronavirus 2019 (COVID-19), fue comunicado en varios países un incremento de las consultas de niñas con pubertad precoz central idiopática (PPCI), sin que contáramos con datos argentinos. Este aumento estaría vinculado con los cambios en el estilo de vida y los niveles de estrés resultantes del aislamiento que afectó particularmente a la población infantil. Objetivos. 1) Describir la evolución de la incidencia de PPCI con requerimiento de inhibición del eje hipotálamo-hipófiso-gonadal (EHHG) en niñas entre 2010 y 2021 en una cohorte del Área Metropolitana de Buenos Aires. 2) Comparar las características de las niñas, con dicho diagnóstico realizado durante la pandemia, con las de un grupo control. Métodos. Serie de tiempo interrumpida y estudio de casos y controles. Resultados. La incidencia anual fue estable entre 2010 y 2017. Desde 2017 hubo un ascenso anual que promedió el 59,9 % (IC95 % 18,6-115,5) y pareciera haberse acelerado durante la pandemia. Constatamos asociación entre haber desarrollado PPCI y haber requerido tratamiento inhibitorio entre el 01 de junio de 2020 y el 31 de mayo de 2021, y dos variables: edad de menarca materna (OR 0,46; IC95 % 0,28-0,77) y antecedente familiar de PPCI (OR 4,42; IC95 % 1,16-16,86). Conclusión. Evidenciamos desde 2017 un aumento significativo en la incidencia de PPCI con requerimiento de inhibición del EHHG. El incremento en la exposición a diversos desencadenantes ambientales durante la pandemia por COVID-19 podría haber ejercido mayor influencia en las niñas con alguna predisposición genética.

Canalización del crecimiento entre los 2 y los 5 años en niños aparentemente sanos con talla baja a los 2 años / Canalization of growth between 2 and 5 years of age in apparently healthy children with short stature at age 2 years

Introducción. El tamaño del recién nacido se asocia a condiciones intrauterinas. El potencial genético se expresa más tarde; la canalización del crecimiento se describe clásicamente hasta los 24 meses. Objetivo. Describir la canalización del crecimiento entre los 2 y los 5 años en niños aparentemente sanos con talla baja a los 2 años. Población y métodos. Estudio de cohorte retrospectiva. Se incluyeron niños seguidos en un hospital universitario de comunidad entre 2003 y 2019, con puntaje Z de talla menor a -2 DE para edad y sexo a los 2 años. Se excluyeron los nacidos prematuros, con bajo peso y con enfermedades crónicas. Se evaluó la trayectoria de crecimiento. Se definió canalización como la adquisición de talla normal para la población general. Resultados. Se incluyeron 64 niños, de los cuales 37 (58 %) presentaron canalización del crecimiento a los 5 años (20 a los 3 años, 8 a los 4 años, y 9 a los 5 años). La velocidad de crecimiento a los 3 y a los 5 años fue significativamente mayor en los que canalizaron en comparación con los que no lo hicieron; hubo una tendencia similar a los 4 años. De los 27 niños con talla baja a los 5 años, 25 tuvieron al menos un registro de velocidad de crecimiento anual menor al percentil 25. Conclusiones. La mayoría de los niños aparentemente sanos con baja talla a los 2 años alcanzan una talla normal a los 5 años. La velocidad de crecimiento anual permite detectar a los niños con riesgo de no canalizar.

Introduction. Newborn size is associated with intrauterine conditions. Genetic potential is expressed later; the canalization of growth is typically described up to 24 months of age. Objective. To describe the canalization of growth between 2 and 5 years of age in apparently healthy children with short stature at age 2 years. Population and methods. Retrospective, cohort study. Children seen at a community teaching hospital between 2003 and 2019, who had a Z-score for height below -2 SDs for age and sex at age 2 years were included. Infants born preterm, with a low birth weight, and chronic conditions were excluded. Growth patterns were assessed. Canalization was defined as reaching a normal stature for the general population. Results. Sixty-four children were included; 37 (58%) showed canalization of growth at 5 years old (20 at 3 years, 8 at 4 years, and 9 at 5 years). The growth rate at 3 and 5 years of age was significantly higher among those who showed canalization compared to those who did not; a similar trend was observed at 4 years of age. Among 27 children with short stature at 5 years of age, 25 had at least 1 annual growth velocity below the 25th centile. Conclusions. Most apparently healthy children with short stature at 2 years old reached a normal stature at 5 years old. The annual growth velocity allows to detect children at risk of not showing canalization.

Blood component requirements in liver transplantation: effect of 2 thromboelastometry-guided strategies for bolus fibrinogen infusion-the TROMBOFIB randomized trial.

BACKGROUND: A low plasma fibrinogen level influences blood component transfusion. Thromboelastometry provides clinical guidance for fibrinogen replacement in liver transplantation (LT). OBJECTIVES: We hypothesized that infusions of fibrinogen concentrate to reach an A10FibTem value of 11 mm during LT could reduce red blood cell (RBC) and other component and fluid requirements in comparison to standard care. METHODS: This randomized, blinded, multicenter trial in 3 hospitals enrolled 189 LT-scheduled patients allocated to an intervention target (A10FibTem, 11 mm) or a standard target (A10FibTem, 8 mm); 176 patients underwent LT with fibrinogen replacement. Data were analyzed by intention-to-treat (intervention group, 91; control group, 85). Blood was extracted, and fibrinogen kits were prepared to bring each patient's fibrinogen level to the assigned target at the start of LT, after portal vein clamping, and after graft reperfusion. The main outcome was the proportion of patients requiring RBC transfusion during LT or within 24 hours. RESULTS: The proportion of patients requiring RBCs did not differ between the groups: intervention, 74.7% (95% CI, 65.5%-83.3%); control, 72.9% (95% CI, 62.2%-82.0%); absolute difference, 1.8% (95% CI, -11.1% to 14.78%) (P = .922). Thrombotic events occurred in 4% of the patients in both groups; reoperation and retransplantation rates and mortality did not differ. Nearly 70% of the patients in both groups required fibrinogen concentrate to reach the target. Using an 11-mm A10FibTem target increased the maximum clot firmness without affecting safety. However, this change provided no clinical benefits. CONCLUSION: The similar low plasma fibrinogen concentrations could explain the lack of significant between-group outcomes.

Canalization of growth between 2 and 5 years of age in apparently healthy children with short stature at age 2 years. / Canalización del crecimiento entre los 2 y los 5 años en niños aparentemente sanos con talla baja a los 2 años.

Introduction. Newborn size is associated with intrauterine conditions. Genetic potential is expressed later; the canalization of growth is typically described up to 24 months of age. Objective. To describe the canalization of growth between 2 and 5 years of age in apparently healthy children with short stature at age 2 years. Population and methods. Retrospective, cohort study. Children seen at a community teaching hospital between 2003 and 2019, who had a Z-score for height below -2 SDs for age and sex at age 2 years were included. Infants born preterm, with a low birth weight, and chronic conditions were excluded. Growth patterns were assessed. Canalization was defined as reaching a normal stature for the general population. Results. Sixty-four children were included; 37 (58%) showed canalization of growth at 5 years old (20 at 3 years, 8 at 4 years, and 9 at 5 years). The growth rate at 3 and 5 years of age was significantly higher among those who showed canalization compared to those who did not; a similar trend was observed at 4 years of age. Among 27 children with short stature at 5 years of age, 25 had at least 1 annual growth velocity below the 25th centile. Conclusions. Most apparently healthy children with short stature at 2 years old reached a normal stature at 5 years old. The annual growth velocity allows to detect children at risk of not showing canalization.

Introducción. El tamaño del recién nacido se asocia a condiciones intrauterinas. El potencial genético se expresa más tarde; la canalización del crecimiento se describe clásicamente hasta los 24 meses. Objetivo. Describir la canalización del crecimiento entre los 2 y los 5 años en niños aparentemente sanos con talla baja a los 2 años. Población y métodos. Estudio de cohorte retrospectiva. Se incluyeron niños seguidos en un hospital universitario de comunidad entre 2003 y 2019, con puntaje Z de talla menor a -2 DE para edad y sexo a los 2 años. Se excluyeron los nacidos prematuros, con bajo peso y con enfermedades crónicas. Se evaluó la trayectoria de crecimiento. Se definió canalización como la adquisición de talla normal para la población general. Resultados. Se incluyeron 64 niños, de los cuales 37 (58 %) presentaron canalización del crecimiento a los 5 años (20 a los 3 años, 8 a los 4 años, y 9 a los 5 años). La velocidad de crecimiento a los 3 y a los 5 años fue significativamente mayor en los que canalizaron en comparación con los que no lo hicieron; hubo una tendencia similar a los 4 años. De los 27 niños con talla baja a los 5 años, 25 tuvieron al menos un registro de velocidad de crecimiento anual menor al percentil 25. Conclusiones. La mayoría de los niños aparentemente sanos con baja talla a los 2 años alcanzan una talla normal a los 5 años. La velocidad de crecimiento anual permite detectar a los niños con riesgo de no canalizar.

Gene Promoter-Methylation Signature as Biomarker to Predict Cisplatin-Radiotherapy Sensitivity in Locally Advanced Cervical Cancer.

Despite efforts to promote health policies focused on screening and early detection, cervical cancer continues to be one of the leading causes of mortality in women; in 2020, estimated 30,000 deaths in Latin America were reported for this type of tumor. While the therapies used to treat cervical cancer have excellent results in tumors identified in early stages, those women who are diagnosed in locally advanced and advanced stages show survival rates at 5 years of <50%. Molecular patterns associated with clinical response have been studied in patients who present resistance to treatment; none of them have reached clinical practice. It is therefore necessary to continue analyzing molecular patterns that allow us to identify patients at risk of developing resistance to conventional therapy. In this study, we analyzed the global methylation profile of 22 patients diagnosed with locally advanced cervical cancer and validated the genomic results in an independent cohort of 70 patients. We showed that BRD9 promoter region methylation and CTU1 demethylation were associated with a higher overall survival (p = 0.06) and progression-free survival (p = 0.0001), whereas DOCK8 demethylation was associated with therapy-resistant patients and a lower overall survival and progression-free survival (p = 0.025 and p = 0.0001, respectively). Our results suggest that methylation of promoter regions in specific genes may provide molecular markers associated with response to treatment in cancer; further investigation is needed.

Homology Modeling and Molecular Dynamics Simulations of Trypanosoma cruzi Phosphodiesterase b1.

Cyclic nucleotide phosphodiesterases have been implicated in the proliferation, differentiation and osmotic regulation of trypanosomatids; in some trypanosomatid species, they have been validated as molecular targets for the development of new therapeutic agents. Because the experimental structure of Trypanosoma cruzi PDEb1 (TcrPDEb1) has not been solved so far, an homology model of the target was created using the structure of Trypanosoma brucei PDEb1 (TbrPDEb1) as a template. The model was refined by extensive enhanced sampling molecular dynamics simulations, and representative snapshots were extracted from the trajectory by combined clustering analysis. This structural ensemble was used to develop a structure-based docking model of the target. The docking accuracy of the model was validated by redocking and cross-docking experiments using all available crystal structures of TbrPDEb1, whereas the scoring accuracy was validated through a retrospective screen, using a carefully curated dataset of compounds assayed against TbrPDEb1 and/or TcrPDEb1. Considering the results from in silico validations, the model may be applied in prospective virtual screening campaigns to identify novel hits, as well as to guide the rational design of potent and selective inhibitors targeting this enzyme.

Clinicopathological and immunohistochemical behavior of ductal carcinoma of the salivary and lacrimal gland in a Mexican Mestizo population.

PURPOSE: Salivary gland tumors are rare and include benign and malignant entities with different behavior and prognosis. Salivary gland carcinoma accounts for 0.2% of all cancers and 5-9% of head and neck carcinomas. We aim to describe the clinicopathological characteristics and discuss the immunohistochemical findings of salivary ductal carcinoma. METHODS: We obtained 17 cases (2.3%) of salivary ductal carcinoma (SDC) from 727 patients with parotid tumors at our cancer center from a database covering a 22-year period (1996-2018). Two pathologists confirmed the diagnosis and excluded 6 cases. Eleven cases were assessed by immunohistochemistry (IHC) for HER2, estrogen receptor (ER), progesterone receptor (PR), androgen receptor (AR), mammaglobin, P53, GATA3, S100, cytokeratins (7,8,14,18, and 20), P63, PAX8, calponin, and SOX10. RESULTS: Eleven SDC cases were in advanced stage, and 80% had metastasis. All cases were surgically treated, and 40% received different adjuvant chemotherapy regimens. we found that most patients were dead of disease. The histological and immunohistochemical analysis showed that 70% of cases were high-grade, 40% were positive for HER2, and 50% for AR. Moreover, a high Ki-67 proliferative index was detected in all cases. We observed luminal differentiation in 50% of cases. CONCLUSION: SDC is a rare entity and survival is very poor. It is histologically similar to ductal carcinoma of the breast. However, important differences exist that help to distinguish them in case of synchronous cancers. The clinical behavior of SDC seems to be more aggressive and IHC analysis is useful for designing therapies.

An AMP-activated protein kinase complex with two distinctive alpha subunits is involved in nutritional stress responses in Trypanosoma cruzi.

Trypanosoma cruzi, the etiological agent of Chagas disease, has a digenetic life cycle. In its passage from the insect vector to the mammalian host, and vice versa, it must be prepared to cope with abrupt changes in environmental conditions, such as carbon source, pH, temperature and osmolarity, in order to survive. Sensing and signaling pathways that allow the parasite to adapt, have unique characteristics with respect to their hosts and other free-living organisms. Many of the canonical proteins involved in these transduction pathways have not yet been found in the genomes of these parasites because they present divergences either at the functional, structural and/or protein sequence level. All of this makes these pathways promising targets for therapeutic drugs. The AMP-activated protein kinase (AMPK) is a serine/threonine kinase activated by environmental stresses such as osmotic stress, hypoxia, ischaemia and exercise that results in reduction of ATP and increase of AMP levels. Thus, AMPK is regarded as a fuel gauge, functioning both as a nutrient and an energy sensor, to maintain energy homeostasis and, eventually, to protect cells from death by nutrient starvation. In the present study we report the characterization of AMPK complexes for the first time in T. cruzi and propose the function of TcAMPK as a novel regulator of nutritional stress in epimastigote forms. We show that there is phosphotransferase activity specific for SAMS peptide in epimastigotes extracts, which is inhibited by Compound C and is modulated by carbon source availability. In addition, TcAMPKα2 subunit has an unprecedented functional substitution (Ser x Thr) at the activation loop and its overexpression in epimastigotes led to higher autophagic activity during prolonged nutritional stress. Moreover, the over-expression of the catalytic subunits resulted in antagonistic phenotypes associated with proliferation. Together, these results point to a role of TcAMPK in autophagy and nutrient sensing, key processes for the survival of trypanosomatids and for its life cycle progression.

Statistical techniques for predicting rupture risk in abdominal aortic aneurysms: A contribution based on bootstrap.

The morphometry of abdominal aortic aneurysms (AAA) has been recognized as one of the main factors that may predispose them to rupture. The need to quantify the morphometry of AAA on a patient-specific basis constitutes a valuable tool for assisting in rupture risk prediction. Previous results of this research group have determined the correlations between hemodynamic stresses and aneurysm morphometry by means of the Pearson coefficient. The present work aims to find how the AAA morphology correlates with the hemodynamic stresses acting on the arterial wall. To do so, the potential of the bootstrap technique has been explored. Bootstrap works appropriately in applications where few data are available (13 patient-specific AAA models were simulated). The methodology developed can be considered a contribution to predicting the hemodynamic stresses from the size and shape indices. The present work explores the use of a specific statistical technique (the bootstrap technique) to predict, based on morphological correlations, the patient-specific aneurysm rupture risk, provide greater understanding of this complex phenomenon that can bring about improvements in the clinical management of aneurysmatic patients. The results obtained using the bootstrap technique have greater reliability and robustness than those obtained by regression analysis using the Pearson coefficient, thus allowing to obtain more reliable results from the characteristics of the samples used, such as their small size and high variability. Additionally, it could be an indicator that other indices, such as AAA length, deformation rate, saccular index, and asymmetry, are important.

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)1.

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field.

Recombinant antibody against Trypanosoma cruzi from patients with chronic Chagas heart disease recognizes mammalian nervous system.

BACKGROUND: To deeply understand the role of antibodies in the context of Trypanosoma cruzi infection, we decided to characterize A2R1, a parasite antibody selected from single-chain variable fragment (scFv) phage display libraries constructed from B cells of chronic Chagas heart disease patients. METHODS: Immunoblot, ELISA, cytometry, immunofluorescence and immunohistochemical assays were used to characterize A2R1 reactivity. To identify the antibody target, we performed an immunoprecipitation and two-dimensional electrophoresis coupled to mass spectrometry and confirmed A2R1 specific interaction by producing the antigen in different expression systems. Based on these data, we carried out a comparative in silico analysis of the protein target´s orthologues, focusing mainly on post-translational modifications. FINDINGS: A2R1 recognizes a parasite protein of ~50 kDa present in all life cycle stages of T. cruzi, as well as in other members of the kinetoplastid family, showing a defined immunofluorescence labeling pattern consistent with the cytoskeleton. A2R1 binds to tubulin, but this interaction relies on its post-translational modifications. Interestingly, this antibody also targets mammalian tubulin only present in brain, staining in and around cell bodies of the human peripheral and central nervous system. INTERPRETATION: Our findings demonstrate for the first time the existence of a human antibody against T. cruzi tubulin capable of cross-reacting with a human neural protein. This work re-emphasizes the role of molecular mimicry between host and parasitic antigens in the development of pathological manifestations of T. cruzi infection.

Case Report: Uterine Adenosarcoma With Sarcomatous Overgrowth and Malignant Heterologous Elements.

A 46- year-old woman presented a uterine adenosarcoma originating in the lower uterine segment. The diagnosis was made in an endometrial biopsy and confirmed in the pathological examination of the complete surgical specimen, both identifying heterologous malignant elements. In addition, complementary immunohistochemical studies were performed. We reviewed the literature, illustrating the clinical and morphological characteristics and the differential diagnoses to be evaluated.