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Plasmacytoid dendritic cells (pDCs) are vital players in antiviral immune responses because of their high levels of IFN-α secretion. However, this attribute has also implicated them as critical factors behind the immunopathogenesis of inflammatory diseases, and no currently available therapy can efficiently inhibit pDCs' aberrant activation. Mesenchymal stromal cells (MSCs) possess stromal immunomodulatory functionality, regulating immune cell activation through several mechanisms, including the adenosinergic (CD39/CD73/adenosine) pathway. The IFN-γ preconditioning of bone marrow MSCs improves their inhibitory properties for therapy applications; however, isolating human gingival tissue-derived MSCs (hGMSCs) is more accessible. These cells have shown better immunomodulatory effects, yet the outcome of IFN-γ preconditioning and its impact on the adenosinergic pathway has not been evaluated. This study first validated the immunoregulatory properties of primary-cultured hGMSCs, and the results showed that IFN-γ preconditioning strengthens CD39/CD73 coexpression, adenosine production, and the regulatory properties of hGMSC, which were confirmed by describing for the first time their ability to reduce pDC activation and their IFN-α secretion and to increase the frequency of CD73+ pDC. In addition, when CD73's enzymatic activity was neutralized in hGMSCs, adenosine production and the IFN-γ preconditioning effect were restrained. This evidence might be applied to design hGMSCs- and adenosine-based immunotherapeutic strategies for treating inflammatory disorders that are associated with pDC overactivation.

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Alpine grassland vegetation supports globally important biodiversity and ecosystems that are increasingly threatened by climate warming and other environmental changes. Trait-based approaches can support understanding of vegetation responses to global change drivers and consequences for ecosystem functioning. In six sites along a 1314 m elevational gradient in Puna grasslands in the Peruvian Andes, we collected datasets on vascular plant composition, plant functional traits, biomass, ecosystem fluxes, and climate data over three years. The data were collected in the wet and dry season and from plots with different fire histories. We selected traits associated with plant resource use, growth, and life history strategies (leaf area, leaf dry/wet mass, leaf thickness, specific leaf area, leaf dry matter content, leaf C, N, P content, C and N isotopes). The trait dataset contains 3,665 plant records from 145 taxa, 54,036 trait measurements (increasing the trait data coverage of the regional flora by 420%) covering 14 traits and 121 plant taxa (ca. 40% of which have no previous publicly available trait data) across 33 families.

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We introduce the FunAndes database, a compilation of functional trait data for the Andean flora spanning six countries. FunAndes contains data on 24 traits across 2,694 taxa, for a total of 105,466 entries. The database features plant-morphological attributes including growth form, and leaf, stem, and wood traits measured at the species or individual level, together with geographic metadata (i.e., coordinates and elevation). FunAndes follows the field names, trait descriptions and units of measurement of the TRY database. It is currently available in open access in the FIGSHARE data repository, and will be part of TRY's next release. Open access trait data from Andean plants will contribute to ecological research in the region, the most species rich terrestrial biodiversity hotspot.

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Type 1 diabetes (T1D) is an autoimmune disease characterized by the destruction of insulin-producing ß-cells of the pancreatic islets by autoreactive T cells, leading to high blood glucose levels and severe long-term complications. The typical treatment indicated in T1D is exogenous insulin administration, which controls glucose levels; however, it does not stop the autoimmune process. Various strategies have been implemented aimed at stopping ß-cell destruction, such as cellular therapy. Dendritic cells (DCs) as an alternative in cellular therapy have gained great interest for autoimmune disease therapy due to their plasticity to acquire immunoregulatory properties both in vivo and in vitro, performing functions such as anti-inflammatory cytokine secretion and suppression of autoreactive lymphocytes, which are dependent of their tolerogenic phenotype, displayed by features such as semimature phenotype, low surface expression of stimulatory molecules to prime T cells, as well as the elevated expression of inhibitory markers. DCs may be obtained and propagated easily in optimal amounts from peripheral blood or bone marrow precursors, such as monocytes or hematopoietic stem cells, respectively; therefore, various protocols have been established for tolerogenic (tol)DCs manufacturing for therapeutic research in the treatment of T1D. In this review, we address the current advances in the use of tolDCs for T1D therapy, encompassing protocols for their manufacturing, the data obtained from preclinical studies carried out, and the status of clinical research evaluating the safety, feasibility, and effectiveness of tolDCs.

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Neutrophil extracellular traps (NETs) are networks of decondensed chromatin loaded with antimicrobial peptides and enzymes produced against microorganisms or biochemical stimuli. Since their discovery, numerous studies made separately have revealed multiple triggers that induce similar NET morphologies allowing to classify them as lytic or non-lytic. However, the variability in NET composition depending on the inducer agent and the local milieu under similar conditions has been scarcely studied. In this work, a comparative study was conducted to evaluate structural and enzymatic divergences in NET composition induced by biochemical (phorbol myristate acetate [PMA] and hypochlorous acid [HOCl]) and microbiologic (Candida albicans, Staphylococcus aureus, and Pseudomonas aeruginosa) stimuli, along with the presence of plasma from healthy donors or patients with systemic lupus erythematosus (SLE). The results showed a differential composition of DNA and the antimicrobial peptide cathelicidin (LL37) and a variable enzymatic activity (neutrophil elastase, cathepsin G, myeloperoxidase) induced by the different stimuli despite showing morphologically similar NETs. Additionally, SLE plasma´s presence increased DNA and LL37 release during NET induction independently of the trigger stimulus but with no enzymatic activity differences. This work provides new evidence about NET composition variability depending on the inducer stimulus and the local milieu.

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It is largely unknown how South America's Andean forests affect the global carbon cycle, and thus regulate climate change. Here, we measure aboveground carbon dynamics over the past two decades in 119 monitoring plots spanning a range of >3000 m elevation across the subtropical and tropical Andes. Our results show that Andean forests act as strong sinks for aboveground carbon (0.67 ± 0.08 Mg C ha-1 y-1) and have a high potential to serve as future carbon refuges. Aboveground carbon dynamics of Andean forests are driven by abiotic and biotic factors, such as climate and size-dependent mortality of trees. The increasing aboveground carbon stocks offset the estimated C emissions due to deforestation between 2003 and 2014, resulting in a net total uptake of 0.027 Pg C y-1. Reducing deforestation will increase Andean aboveground carbon stocks, facilitate upward species migrations, and allow for recovery of biomass losses due to climate change.

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Sjogren´s syndrome (SS) is an autoimmune disease whose pathogenesis is characterized by an exacerbated T cell infiltration in exocrine glands, markedly associated to the inflammatory and detrimental features as well as the disease progression. Several helper T cell subsets sequentially converge at different stages of the ailment, becoming involved in specific pathologic roles. Initially, their activated phenotype endows them with high migratory properties and increased pro-inflammatory cytokine secretion in target tissues. Later, the accumulation of immunomodulatory T cells-derived factors, such as IL-17, IFN-γ, or IL-21, preserve the inflammatory environment. These effects favor strong B cell activation, instigating an extrafollicular antibody response in ectopic lymphoid structures mediated by T follicular helper cells (Tfh) and leading to disease progression. Additionally, the memory effector phenotype of CD8+ T cells present in SS patients suggests that the presence of auto-antigen restricted CD8+ T cells might trigger time-dependent and specific immune responses. Regarding the protective roles of traditional regulatory T cells (Treg), uncertain evidence shows decrease or invariable numbers of circulating and infiltrating cells. Nevertheless, an emerging Treg subset named follicular regulatory T cells (Tfr) seems to play a critical protective role owing to their deficiency that enhances SS development. In this review, the authors summarize the current knowledge of T cells subsets contribution to the SS immunopathology, focusing on the cellular and biomolecular properties allowing them to infiltrate and to harm target tissues, and that simultaneously make them key therapeutic targets for SS treatment.

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Unexpected anti-red blood cell (RBC) alloantibodies are routinely investigated in immunohematology and blood banking since their existence in pregnant women may induce haemolytic disease of the foetus and newborn, and their presence in donors may induce haemolytic transfusion reactions or hyperacute rejection in solid organ transplantation. Unexpected anti-RBC alloantibodies may target antigens of the most blood types excluding the expected antibodies targeting the ABO antigens. Their incidence in humans was originally linked to alloimmunization events such as blood transfusions, transplants, or pregnancies. But later, many findings revealed their existence in pathogenic processes such as malignancies, infections, and autoimmune diseases; and usually (but not always) associated to autoimmune haemolytic anaemia (AIHA). Nevertheless, unexpected anti-RBC autoantibodies are also occasionally found in healthy individuals in the absence of AIHA and with no history of alloimmunization or the associated pathologic processes. Hence, they are generally known as non-clinically significant, are excluded for typification and called "silent red blood cell autoantibodies (SRBCAA)". This review highlights evidence related to genetic predisposition, molecular mimicry, immune dysregulation, and immune tolerance loss surrounding the existence of anti-RBC antibodies, describing the presence of SRBCAA as possible early witnesses of the development of autoimmune diseases.

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Our knowledge about the structure and function of Andean forests at regional scales remains limited. Current initiatives to study forests over continental or global scales still have important geographical gaps, particularly in regions such as the tropical and subtropical Andes. In this study, we assessed patterns of structure and tree species diversity along ~ 4000 km of latitude and ~ 4000 m of elevation range in Andean forests. We used the Andean Forest Network (Red de Bosques Andinos, https://redbosques.condesan.org/) database which, at present, includes 491 forest plots (totaling 156.3 ha, ranging from 0.01 to 6 ha) representing a total of 86,964 identified tree stems ≥ 10 cm diameter at breast height belonging to 2341 identified species, 584 genera and 133 botanical families. Tree stem density and basal area increases with elevation while species richness decreases. Stem density and species richness both decrease with latitude. Subtropical forests have distinct tree species composition compared to those in the tropical region. In addition, floristic similarity of subtropical plots is between 13 to 16% while similarity between tropical forest plots is between 3% to 9%. Overall, plots ~ 0.5-ha or larger may be preferred for describing patterns at regional scales in order to avoid plot size effects. We highlight the need to promote collaboration and capacity building among researchers in the Andean region (i.e., South-South cooperation) in order to generate and synthesize information at regional scale.

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Liverworts and mosses are a major component of the epiphyte flora of tropical montane forest ecosystems. Canopy access was used to analyse the distribution and vertical stratification of bryophyte epiphytes within tree crowns at nine forest sites across a 3400 m elevational gradient in Peru, from the Amazonian basin to the high Andes. The stable isotope compositions of bryophyte organic material (13C/12C and 18O/16O) are associated with surface water diffusive limitations and, along with C/N content, provide a generic index for the extent of cloud immersion. From lowland to cloud forest δ13C increased from -33‰ to -27‰, while δ18O increased from 16.3‰ to 18.0‰. Epiphytic bryophyte and associated canopy soil biomass in the cloud immersion zone was estimated at up to 45 t dry mass ha-1, and overall water holding capacity was equivalent to a 20 mm precipitation event. The study emphasizes the importance of diverse bryophyte communities in sequestering carbon in threatened habitats, with stable isotope analysis allowing future elevational shifts in the cloud base associated with changes in climate to be tracked.

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El procedimiento de Manougian es una de las técnicas empleadas para la ampliación del anillo aórtico en los casos de anulus pequeño o discordancia válvulo-protésico-paciente, que se utiliza con el fin de implantar una válvula de mayor tamaño y así evitar las complicaciones derivadas de una prótesis pequeña para el área corporal del paciente. Se presenta el caso de una mujer adulta joven con antecedente de reemplazo valvular aórtico el cual se encuentra con estenosis severa, quien presenta en el intraoperatorio un anillo valvular estrecho que requiere de las técnicas de ampliación del anillo aórtico para la implantación de una prótesis adecuada

Manougian ́s procedure is one of the techniques used for aortic annulus enlargement in cases of small aortic annuli or patient-prosthesis mismatch. The benefit of this procedure is the implantation of a bigger valve prosthesis thus avoiding the size of the aortic prosthesis to be too small for the patient ́s body surface. A case is presented in a young adult woman with a history of aortic valve replacement with severe stenosis and a narrow aortic annulus which was evidenced during the intraoperative period, requiring aortic annulus enlargement techniques to be used to implant a suitable prosthesis

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Incadendron esseri K.Wurdack & Farfan, gen. & sp. nov., from the wet sub-Andean cordilleras of Ecuador (Cordillera del Cóndor) and Peru (Cusco, Oxapampa) is described and illustrated. This recently discovered large canopy tree with a narrow elevational range presents an unusual combination of rare morphological characters in Hippomaneae including mucilage-secreting sheathing stipules, conduplicate ptyxis, and large, woody fruits. The broader significance of these characters in Hippomaneae is discussed. The morphology and anatomy of Incadendron were investigated, highlighting its fruit similarities with Guiana Shield endemic Senefelderopsis, and the systematics value of ptyxis variation, which remains poorly studied for the family.

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Although the Amazon rainforest houses much of Earth's biodiversity and plays a major role in the global carbon budget, estimates of tree biodiversity originate from fewer than 1,000 forest inventory plots, and estimates of carbon dynamics are derived from fewer than 200 recensus plots. It is well documented that the pre-European inhabitants of Amazonia actively transformed and modified the forest in many regions before their population collapse around 1491 AD; however, the impacts of these ancient disturbances remain entirely unaccounted for in the many highly influential studies using Amazonian forest plots. Here we examine whether Amazonian forest inventory plot locations are spatially biased toward areas with high probability of ancient human impacts. Our analyses reveal that forest inventory plots, and especially forest recensus plots, in all regions of Amazonia are located disproportionately near archaeological evidence and in areas likely to have ancient human impacts. Furthermore, regions of the Amazon that are relatively oversampled with inventory plots also contain the highest values of predicted ancient human impacts. Given the long lifespan of Amazonian trees, many forest inventory and recensus sites may still be recovering from past disturbances, potentially skewing our interpretations of forest dynamics and our understanding of how these forests are responding to global change. Empirical data on the human history of forest inventory sites are crucial for determining how past disturbances affect modern patterns of forest composition and carbon flux in Amazonian forests.

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General patterns of forest dynamics and productivity in the Andes Mountains are poorly characterized. Here we present the first large-scale study of Andean forest dynamics using a set of 63 permanent forest plots assembled over the past two decades. In the North-Central Andes tree turnover (mortality and recruitment) and tree growth declined with increasing elevation and decreasing temperature. In addition, basal area increased in Lower Montane Moist Forests but did not change in Higher Montane Humid Forests. However, at higher elevations the lack of net basal area change and excess of mortality over recruitment suggests negative environmental impacts. In North-Western Argentina, forest dynamics appear to be influenced by land use history in addition to environmental variation. Taken together, our results indicate that combinations of abiotic and biotic factors that vary across elevation gradients are important determinants of tree turnover and productivity in the Andes. More extensive and longer-term monitoring and analyses of forest dynamics in permanent plots will be necessary to understand how demographic processes and woody biomass are responding to changing environmental conditions along elevation gradients through this century.

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Symptomatic cholelithiasis is a highly prevalent disease in Colombia, though its presentation in patients with situs inversus totalis has rarely been described. This report describes the case of a patient with symptomatic cholelithiasis and situs inversus totalis who underwent a single-port laparoscopic surgery after concomitant gallstones were ruled out. This procedure is a minimally invasive technique of SILS (Single Incision Laparoscopic Surgery). Situs Inversus is a rare genetic disorder which is characterized by the transposition of the abdominal and chest organs through the sagittal plane, having a so-called "mirror image" effect. While the etiology is still unclear, it is often attributed to a genetic predisposition caused by an autosomal recessive gene of incomplete penetrance. The presence of symptomatic vesicular lithiasis in a patient with SIT not only creates diagnostic doubt but also presents a real challenge for treatment as any surgical procedure (especially laparoscopic cholecystectomy) will be more difficult due to the anatomical abnormalities of the patient.

La colelitiasis sintomática es una enfermedad altamente prevalente en Colombia, aunque rara vez se ha descrito su presentación en pacientes con situs inversus totalis. Este informe describe el caso de un paciente con colelitiasis sintomática y situs inversus totalis que se sometió a una cirugía laparoscópica de puerto único después de descartar cálculos biliares concomitantes. Este procedimiento es una técnica mínimamente invasiva de SILS (cirugía laparoscópica de incisión única). Situs Inversus es un raro trastorno genético que se caracteriza por la transposición de los órganos abdominales y del tórax a través del plano sagital, teniendo el llamado efecto de "imagen especular". Si bien la etiología aún no está clara, a menudo se atribuye a una predisposición genética causada por un gen autosómico recesivo de penetración incompleta. La presencia de litiasis vesicular sintomática en un paciente con TIE no solo crea dudas diagnósticas sino que también presenta un desafío real para el tratamiento ya que cualquier procedimiento quirúrgico (especialmente la colecistectomía laparoscópica) será más difícil debido a las anormalidades anatómicas del paciente.

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Se revisa las manifestaciones clínicas y diagnósticas de la peritonitis tuberculosa. Para ello se aporta nuestra experiencia en un caso: mujer de 27 años de edad, secundigesta, sin pareja sexual desde hace seis meses, menstruaciones regulares, flujo regular que dura 5 días. Las manifestaciones clínicas más frecuentes fue dolor pélvico y abdominal difuso, dismenorrea, malestar general, líquido en fondo de saco de Douglas y ocasionalmente fiebre vespertina. El mantoux fue negativo. El líquido peritoneal presentó características de exudado de predominio linfocitario y la determinación de adenosina deaminasa resultó elevada en este caso. El diagnóstico se realizó mediante laparoscopía con biopsia peritoneal que demostró la presencia de granulomas necrotizantes. La paciente respondió positivamente al tratamiento específico.

We check the clinical and diagnostic signs of tuberculous peritonitis. For this, we contribute our experience in one case: a 27 years old female, secundigravid, with no sexual partner six months ago, irregular menstruations, regular flow lasting 5 days. The most frequent clinical signs were pelvic pain, and diffuse abdominal pain, dysmenorrheal, general malaise, liquid in the Douglas cul-de-sac and occasionally evening fever. Mantoux test: negative. Peritoneal liquid showed exudates features predominantly lymphocytic and adenosine deaminase value was raised in this case. Diagnosis was made through laparoscopy and peritoneal biopsy that showed the presence of necrotizing granulomas. The patient responded positively to the specific treatment.

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La obstrucción del intestino delgado es una de las patologías quirúrgicas abdominales más frecuentes atendidas por los cirujanos en los servicios de urgencias. Se trata de un síndrome con múltiples causas; una particularmente interesante es la endometriosis intestinal, la cual ocurre hasta en el 37% de 1as pacientes con esta patología. Sin embargo, la mayoría no experimenta síntomas relacionados con el tracto gastrointestinal.Presentamos el caso de una mujer de 40 años de edad, con obstrucción intestinal secundaria a esta entidad, la cual requirió resección quirúrgica con anastomosis primaria. La evaluación patológica demostró endometriosis extensa del intestino delgado, que producía estenosis completa del lumen intestinal. Este informe reporta una de las raras, aunque significativas complicaciones de la endometriosis extrapélvica: la obstrucción intestinal. De ahí que, la endometriosis del tracto digestivo, debe incluirse en el diagnóstico diferencial de aquellas pacientes con obstrucción intestinal, que se encuentren en edad reproductiva.

Intestinal obstruction is one of the most frequent abdominal surgical pathologies assisted by the surgeons at emergency services. It involves a multifactorial syndrome, being one of particular interest, intestinal endometriosis, which accounts to almost 37% of patients with this entity. However, the majority does not present gastrointestinal symptoms.We present the case of a 40 year old female, with obstruction due to this pathology, who required surgical resection with primary anastomosis intestinal. The histopathological evaluation revealed extense endometriosis of small intestine, with total stenosis of the lumen. This work reports one uncommon but significative complication of extra pelvic endometriosis: intestinal obstruction. Hence, the endometriosis of digestive tract should be included in the differential diagnosis of those patients with intestinal obstruction; in between reproductive age.

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Veintidós años después de la notificación de la primera prueba clínica del SIDA, el VIH se ha propagado en todos los rincones del mundo. En la actualidad la epidemia sigue creciendo rápidamente, quitándole la vida a millones de personas. Al finalizar el 2002 el SIDA había matado más de 22 millones de personas reduciendo la esperanza de vida y aumentando la mortalidad infantil. Cerca de la mitad de los casos de SIDA en el mundo se han registrado en el continente americano.En América Latina la epidemia se manifiesta de manera concentrada, es decir afecta principalmente a personas pobres con bajo nivel educativo y con falta de acceso a los servicios básicos de salud, causando discriminación a quienes la padecen. Los niños son también víctimas frecuentes. En los países en desarrollo alrededor de un tercio de los nacidos de madres con el VIH se contagian durante el embarazo o el nacimiento o a través de la leche materna; los efectos sobre los niños, sin embargo, no se limitan al contagio sino además a que quedarán huérfanos antes de los 15 años de edad.La principal arma para luchar contra la epidemia es la prevención, para ello es preciso que la población tenga un conocimiento adecuado sobre la enfermedad, sus mecanismos de contagio y la forma de prevenirla.

Twenty- two years after the first clinical test of AIDS were done, HIV has spread around the world. At the moment the epidemic is growing rapidly taking millions of lives. At the end of 2002 AIDS has killed over 22 million people reducing the hope of life and increasing infantile mortality. Close to half of cases of AIDS in the world has been registered in the American continent.In Latin America the epidemic affects mainly poor people with low level of education and a limited access to basic medical services causing a discrimination to those who have the disease. The children are the most common victims. In developing countries almost one third of children born to mothers with HIV were infected during the pregnancy or after by breastfeeding. The effects it has on the children is not only limited to contracting the disease but becoming orphans before they are fifteen years old.

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