Compilation of Evidence Supporting the Role of a T Helper 2 Reaction in the Pathogenesis of Acute Appendicitis.

Despite being the most common abdominal surgical emergency, the cause of acute appendicitis (AA) remains unclear, since in recent decades little progress has been made regarding its etiology. Obstruction of the appendicular lumen has been traditionally presented as the initial event of AA; however, this is often the exception rather than the rule, as experimental data suggest that obstruction is not an important causal factor in AA, despite possibly occurring as a consequence of the inflammatory process. Type I hypersensitivity reaction has been extensively studied, involving Th2 lymphocytes, and cytokines such as IL-4, IL-5, IL-9 and IL-13, which have well-defined functions, such as a positive-feedback effect on Th0 for differentiating into Th2 cells, recruitment of eosinophils and the release of eosinophilic proteins and the production of IgE with the activation of mast cells, with the release of proteins from their granules. Cytotoxic activity and tissue damage will be responsible for the clinical manifestation of the allergy. AA histological features are similar to those found in allergic reactions like asthma. The intestine has all the components for an allergic immune response. It has contact with hundreds of antigens daily, most of them harmless, but some can potentially induce an allergic response. In recent years, researchers have been trying to assess if allergy is a component of AA, with their latest advances in the understanding of AA as a Th2 reaction shown by the authors of this article.

The influence of carvedilol posology timing on clinically significant portal hypertension: insights from elastography measurements.

BACKGROUND AND AIMS: Carvedilol has emerged as the preferred ß-blocker for treating portal hypertension. However, there is still a debate in dosing regimen, with a potential lower bioavailability in once-daily regimens. The aim of this study is to assess the acute effects of carvedilol posology in patients with clinically significant portal hypertension (CSPH), as a surrogate marker of bioavailability. METHODS: In this experimental study, 34 patients with CSPH receiving carvedilol twice daily were asked to suppress the night dose of carvedilol, creating a standardized 24-hour dose interval. Spleen stiffness measurement (SSM) and liver stiffness measurement (LSM) by transient elastography (TE) were performed, with the exact interval between the last carvedilol administration and TE measurements consistently maintained at 24 hours and compared with values prior and under treatment. RESULTS: Thirty-four patients were included, predominantly male (82.9%). SSM after suspending carvedilol for 24 hours [mean, 73.9kPa (SD, 17.0)] was significantly higher ( P < 0.001) than under treatment [mean, 56.3kPa (SD, 13.2)] and was not significantly different ( P = 0.908) from SSM prior to introduction of carvedilol [mean, 74.5kPa (SD, 12.4)]. Differences were also found in stratified analysis for carvedilol dosage, D'Amico classification stages, MELDNa scores, MELD3.0 scores, Child-Pugh class A and CSPH due to alcoholic cirrhosis. LSM after suspension was not significantly different from both under treatment and prior to treatment. CONCLUSION: The differences in SSM after skipping one dose of carvedilol show both the importance of strict adherence to the prescribed dosing regimen to achieve the expected therapeutic benefits and the impact of twice daily prescription in bioavailability throughout the day.

Tryptase in Acute Appendicitis: Unveiling Allergic Connections through Compelling Evidence.

The aetiology of acute appendicitis (AA), the most frequent abdominal surgical emergency, is still unclarified. Recent epidemiologic, clinical and laboratorial data point to an allergic component in the pathophysiology of AA. Mastocytes participate in the Th2 immune response, releasing inflammatory mediators from their granules upon stimulation by IgE-specific antigens. Among the well-known mediators are histamine, serotonin and tryptase, which are responsible for the clinical manifestations of allergies. We conducted a prospective single-centre study to measure histamine and serotonin (commercial ELISA kit) and tryptase (ImmunoCAP System) concentrations in appendicular lavage fluid (ALF) and serum. Consecutive patients presenting to the emergency department with a clinical diagnosis of AA were enrolled: 22 patients with phlegmonous AA and 24 with gangrenous AA The control group was composed of 14 patients referred for colectomy for colon malignancy. Appendectomy was performed during colectomy. Tryptase levels were strikingly different between histological groups, both in ALF and serum (p < 0.001); ALF levels were higher than serum levels. Tryptase concentrations in ALF were 109 times higher in phlegmonous AA (APA) (796.8 (194.1-980.5) pg/mL) and 114 times higher in gangrenous AA (AGA) (837.4 (272.6-1075.1) pg/mL) than in the control group (7.3 (4.5-10.3) pg/mL. For the diagnosis of AA, the discriminative power of serum tryptase concentration was good (AUC = 0.825), but discriminative power was weak (AUC = 0.559) for the differential diagnosis between APA and AGA. Mastocytes are involved in AA during clinical presentations of both phlegmonous and gangrenous appendicitis, and no significant differences in concentration were found. No differences were found in serum and ALF concentrations of histamine and serotonin between histological groups. Due to their short half-lives, these might have elapsed by the time the samples were collected. In future research, these determinations should be made immediately after appendectomy. Our findings confirm the hypersensitivity type I reaction as an event occurring in the pathogenesis of AA: tryptase levels in ALF and serum were higher among patients with AA when compared to the control group, which is in line with a Th2 immune response and supports the concept of the presence of an allergic reaction in the pathogenesis of acute appendicitis. Our results, if confirmed, may have clinical implications for the treatment of AA.

Emergency department contribution to HCV elimination in the Iberian Peninsula.

BACKGROUND: Undiagnosed cases of hepatitis C virus (HCV) infection result in significant morbidity and mortality, further transmission, and increased public health costs. Testing in emergency departments (EDs) is an opportunity to expand HCV screening. The goal of this project was to increase the proportion of eligible patients screened for HCV in urban areas. METHODS: An opportunistic automated HCV screening program was implemented in the EDs of 4 public hospitals in Spain and Portugal at different periods between 2018 and 2023. HCV prevalence was prospectively evaluated, and single-step or reflex testing was used for confirmation in the same sample. RESULTS: More than 90% of the population eligible for testing were screened in the participating centers. We found HCV antibody seroprevalence rates ranging from 0.6 to 3.9%, with between 19 and 53% of viremic individuals. CONCLUSIONS: Opportunistic HCV screening in EDs is feasible, does not disrupt ED activities, is highly effective in increasing diagnosis, and contributes to WHO's HCV elimination goals.

Treating Advanced Hepatocellular Carcinoma with Sorafenib: A 10-Year Single Center Experience.

Introduction: Sorafenib was the first therapy used for systemic treatment of unresectable hepatocellular carcinoma (HCC). Multiple prognosis factors associated with sorafenib therapy have been described. Objectives: The aim of this work was to evaluate survival and time to progression (TTP) on HCC patients treated with sorafenib, and check for predictive factors of sorafenib benefit. Materials and Methods: Retrospectively, data from all HCC patients treated with sorafenib in a Liver Unit from 2008 to 2018 were collected and analyzed. Results: Sixty-eight patients were included; 80.9% were male, the median age was 64.5 years, 57.4% had Child-Pugh A cirrhosis and 77.9% were BCLC stage C. Macrovascular invasion (MVI) was present in 25% of the patients and 25% of the subjects had other extrahepatic metastasis. The median survival was 10 months (IQR 6.0-14.8) and median TTP was 5 months (IQR 2.0-7.0). Survival and TTP were similar between Child-Pugh A and B patients: 11.0 months (IQR 6.0-18.0) for Child-Pugh A and 9.0 months (IQR 5.0-14.0) for Child-Pugh B (p = 0.336). In univariate analysis, larger lesion size (LS >5 cm), higher alpha-fetoprotein (AFP >50 ng/mL), and no history of locoregional therapy were statistically associated with mortality (HR 2.17, 95% CI 1.24-3.81; HR 3.49, 95% CI 1.90-6.42; HR 0.54, 95% CI 0.32-0.93, respectively), but only LS and AFP were independent predictive factors, as shown in multivariate analysis (LS: HR 2.08, 95% CI 1.10-3.96; AFP: HR 3.13, 95% CI 1.59-6.16). MVI and LS >5 cm were associated with TTP shorter than 5 months in univariate analysis (MVI: HR 2.80, 95% CI 1.47-5.35; LS: HR 2.1, 95% CI 1.08-4.11), but only MVI was an independent predictive factor of TTP shorter than 5 months (HR 3.42, 95% CI 1.72-6.81). Regarding safety data, 76.5% of patients reported at least one side effect (any grade), and 19.1% presented grade III-IV adverse effects leading to treatment discontinuation. Conclusions: We observed no significant difference in survival or TTP in Child-Pugh A or Child-Pugh B patients treated with sorafenib, as compared to more recent real-life studies. Lower primary LS and AFP were associated with a better outcome, and lower AFP was the main predictor of survival. The reality of systemic treatment for advanced HCC has recently changed and continues to evolve, but sorafenib remains a viable therapeutic option.

Introdução: O sorafenib foi o primeiro fármaco usado em primeira linha na terapêutica sistémica do carcinoma hepatocelular (CHC) em estadio avançado. Têm sido descritos múltiplos factores modificadores de prognóstico associados à sua utilização. Objectivos: Caracterizar um grupo de doentes com CHC que realizaram terapêutica com sorafenib, estudar a sobrevivência e o tempo até progressão (TAP), e avaliar os factores preditores de benefício. Material e Métodos: Estudo retrospectivo com recolha e análise dos dados relativos a todos os doentes com CHC tratados com sorafenib numa Unidade de Hepatologia, entre 2008 e 2018. Resultados: Foram incluídos no estudo sessenta e oito doentes; 80.9% do sexo masculino, com mediana de idades de 64.5 anos, 57.4% tinham cirrose em estadio A de Child-Pugh e 77.9% apresentavam CHC em estadio C do Barcelona Clínic Liver Cancer (BCLC). A invasão macrovascular (IMV) estava presente em 25% dos doentes, e também 25% dos doentes tinha metastização extra-hepática (que não a IMV). A mediana de sobrevivência foi de 10 meses (IQR 6.0-14.8) e a mediana de TAP foi de 5 meses (IQR 2.0­7.0). A sobrevivência e o TAP foram similares nos doentes Child-Pugh A e B: 11.0 meses (IQR 6.0­18.0) para Child-Pugh A e 9.0 meses (IQR 5.0­14.0) para Child-Pugh B (p = 0.336). Na análise univariada, o tamanho da lesão >5 cm (TL), alfa-fetoproteína > 50 ng/mL (AFP) e a ausência de terapêuticas locorregionais prévias (TLP) tiveram relação estatisticamente significativa com a mortalidade (TL: HR 2.17, 95% CI 1.24­3.81; AFP: HR 3.49, 95% CI 1.90­6.42; TLP: HR 0.54, 95% CI 0.32­0.93), mas apenas o TL e AFP foram fatores preditores independentes, como mostrou a análise multivariada (TL: HR 2.08, 95% CI 1.10­3.96; AFP: HR 3.13, 95% CI 1.59­6.16). A IMV e o TL >5 cm estiveram associados com o TAP <5 meses na análise univariada (IMV: HR 2.80, 95% CI 1.47­5.35; TL: HR 2.1, 95% CI 1.08­4.11), mas apenas a IMV foi um fator preditor independente de TAP <5 meses (HR 3.42, 95% CI 1.72­6.81). Relativamente aos dados de segurança, 76.5% dos doentes relataram pelo menos um efeito lateral (qualquer grau), e 19.1% apresentaram efeitos adversos de grau III-IV, que levaram à suspensão do fármaco. Conclusões: Não foi observada diferença significativa na sobrevivência ou no tempo até progressão nos doentes Child-Pugh A ou Child-Pugh B tratados com sorafenib, quando comparado com estudos real-life recentes. Menor TL e AFP estiveram associados a melhor outcome e um valor de AFP baixo mostrou-se o principal preditor de sobrevivência. A realidade da terapêutica sistémica para o CHC avançado alterou-se recentemente e continua em mudança, mas o sorafenib permanece uma alternativa terapêutica viável.

Eosinophil Granule Proteins Involvement in Acute Appendicitis-An Allergic Disease?

Several pieces of evidence point to an allergic component as a trigger of acute appendicitis. As the Th2 immune response is characterized by eosinophil mobilization to the target organ and release of their cationic granule proteins, it is reasonable to investigate if the degranulation of eosinophils could be associated with the local injury. The primary aim of this study is to evaluate the participation of eosinophils granules proteins in acute appendicitis, both at local and systemic levels and the secondary aim is to evaluate the diagnostic accuracy of eosinophils granules proteins for the detection of acute appendicitis, as well as for distinguishing between complicated and uncomplicated acute appendicitis. Eosinophil-derived neurotoxin (EDN), eosinophil cationic protein (ECP) and eosinophil peroxidase (EP) are the most well-known eosinophil granule proteins. From August 2021 to April 2022, we present a prospective single-center study to evaluate the EDN, ECP, and EP concentrations simultaneously in appendicular lavage fluid (ALF) and the serum of 22 patients with acute phlegmonous appendicitis (APA), 24 with acute gangrenous appendicitis (AGA), and 14 normal controls. Concerning EDN, no differences were found between groups. ECP concentrations in ALF and serum were significantly higher in the histologically confirmed acute appendicitis compared to the control groups (p < 0.0001 and p < 0.0001, respectively). In ALF, no differences were found between ECP levels in APA: 38.85 ng/mL (IQR 26.50-51.77) and AGA 51.55 ng/mL (IQR 39.55-70.09) groups (p = 0.176). In the serum, no difference was found between ECP levels at APA: 39 ng/mL (IQR 21.30-56.90) and AGA: 51.30 ng/mL (IQR 20.25-62.59) (p = 0.100). For EP, the concentrations in ALF (p < 0.001) and serum (p < 0.001) were both higher in acute appendicitis compared to the control. In ALF, no difference was found between APA: 240.28 ng/mL (IQR 191.2-341.3) and AGA: 302.5 (IQR 227.7-535.85) (p = 0.236). In the serum, no differences were found between APA: 158.4 ng/mL (IQR 111.09-222.1) and AGA: 235.27 (IQR 192.33-262.51) (p = 0.179). Globally, the ALF concentrations were higher than serum concentrations, reflecting an intense inflammatory local reaction in AA. The optimal ECP cut-off for discriminating between acute appendicitis and the controls was >11.41 ng/mL, with a sensitivity of 93.5%, but with a specificity for identifying appendicitis of 21.4%, good discriminative power (AUC = 0.880). For EP, the optimal cut-off was >93.20 ng/mL, with a sensitivity of 87%, but with a specificity of 14.3% (AUC = 0.901), excellent discriminative power. For the diagnosis of perforated AA, the discriminative power of ECP and EP serum concentrations are weak (AUC = 0.562 and AUC = 0.664, respectively). Concerning the presence of peritonitis, the discriminative power of ECP and EP serum concentrations is acceptable, respectively: AUC = 0.724 and AUC = 0.735. Serum levels of EDN (p = 0.119), ECP (p = 0.586) and EP (p = 0.08) in complicated appendicitis were similar to uncomplicated appendicitis. Serum concentrations of ECP and EP can be added to decision-making AA diagnosis. A Th2-type immune response is present in AA. These data bring forward the role of an allergic reaction in the pathogenesis of acute appendicitis.

Detailed stratified GWAS analysis for severe COVID-19 in four European populations.

Given the highly variable clinical phenotype of Coronavirus disease 2019 (COVID-19), a deeper analysis of the host genetic contribution to severe COVID-19 is important to improve our understanding of underlying disease mechanisms. Here, we describe an extended genome-wide association meta-analysis of a well-characterized cohort of 3255 COVID-19 patients with respiratory failure and 12 488 population controls from Italy, Spain, Norway and Germany/Austria, including stratified analyses based on age, sex and disease severity, as well as targeted analyses of chromosome Y haplotypes, the human leukocyte antigen region and the SARS-CoV-2 peptidome. By inversion imputation, we traced a reported association at 17q21.31 to a ~0.9-Mb inversion polymorphism that creates two highly differentiated haplotypes and characterized the potential effects of the inversion in detail. Our data, together with the 5th release of summary statistics from the COVID-19 Host Genetics Initiative including non-Caucasian individuals, also identified a new locus at 19q13.33, including NAPSA, a gene which is expressed primarily in alveolar cells responsible for gas exchange in the lung.

Analysis of the optical properties of the silvery spots on the wings of the Gulf Fritillary, Dione vanillae.

The ventral face of the wings of the butterfly Dione vanillae is covered with bright and shiny silvery spots. These areas contain densely packed ground- and coverscales with a bright metallic appearance reflecting more than 50% of light uniformly over the visible range. Our analysis shows that this optically attractive feature is caused by the inner microstructure of the scales located in these areas. Electron microscopy of cross sections through the scales shows that upper and lower lamina, supporting trabeculae, and topping ridges can be approximated by a 'circus tent'-like geometry. By simulating its optical properties, we show that a moderate disorder of this geometry is important for the uniform reflection of light resulting in the silvery appearance.

Stakeholders' perceptions of appropriate nature-based solutions in the urban context.

The concept of nature-based solutions (NBSs) has become increasingly popular among urban policymakers and planners to help them tackle the urban challenges arising from urban expansion and climate change. Stakeholders' involvement is a fundamental step, and stakeholders' perceptions and preferences can affect the development of NBS projects. This study aims to identify stakeholders' perceptions of the most critical urban challenges, the priority interventions, the preferred NBSs and the benefits of the NBSs, and to identify the determinants of these perceptions. A survey was administered to assess stakeholders' perceptions and views on implementing NBSs in two Portuguese cities with distinct urban, geographical, and socio-economic contexts. A binary logistic regression model was used to understand the determinants of the likelihood of the stakeholders' answers. According to the stakeholders, climate change is one of the main concerns in the urban context. It is usually associated with the incidence of heatwaves and water scarcity. Additionally, stakeholders are concerned about the low quantity and poor management of green spaces (GSs). They believe that it will be necessary to increase the GS, to recover some degraded areas, and to increase mobility. The preferred NBSs were planting more urban trees, making green shaded areas, and rehabilitating riverbanks. The main expected benefits were benefits for leisure and relaxation, reductions in air temperature, purer air, and improvements in public health. The results showed mostly coherent connections between the main concerns/priorities of the stakeholders and the perceived NBS benefits; however, some stakeholders did not present coherent connections, indicating low awareness of the current policy for implementing NBSs to overcome existing and future urban challenges.

One-quarter of chronic hepatitis D patients reach HDV-RNA decline or undetectability during the natural course of the disease.

BACKGROUND: Spontaneous HDV-RNA fluctuations, assessed by nonstandardised in-house assays, have been reported during the course of chronic hepatitis delta (CHD). AIMS: To evaluate changes in serum HDV-RNA concentrations in untreated CHD patients and correlate these changes with other HBV markers. METHODS: A total of 323 consecutive serum samples from 56 CHD patients (detectable HDV-RNA) followed for >3 years were retested for HDV-RNA levels by a sensitive technique using the first WHO international HDV-RNA standard. Quantitative HBsAg, HBV-DNA, and HBV-RNA were also determined. RESULTS: Most participants were male, middle-aged, white European, and HBeAg-negative (82%). Almost half had liver cirrhosis and 64% were receiving nucleos(t)ide analogues. At inclusion, median-HDV-RNA was 5.3 (4.2-6.5) log10 IU/mL, HBsAg 4.0 (3.5-4.3) log10 IU/mL, and HBV-DNA 1.6 (1.0-2.6) log10 IU/mL; ALT values were normal in 13 (23%). During a mean follow-up of 5.6 (3-16) years, 14 (25%) showed ≥2log10 HDV-RNA decline, including 11 (20%) who spontaneously achieved undetectable HDV-RNA. Four patients (7%) lost HBsAg, with undetectable HDV-RNA. The remaining 42 (75%) had persistently detectable HDV-RNA. During follow-up, patients with a ≥2log10 HDV-RNA decline showed a greater HBsAg drop (-0.7 ± 1.1 vs -0.09 ± 0.9 log IU/mL; P = 0.039) than those with a <2 log10 HDV-RNA decline. Overall, ALT and HBV-DNA levels decreased over time. There were no differences in clinical outcomes between groups. CONCLUSIONS: One-quarter of untreated CHD patients showed a ≥2log10 decline in HDV-RNA and 20% reached HDV-RNA undetectability during a mean follow-up of 5.6 years. The decline was associated with ALT decrease. These findings have implications for designing new therapies for CHD.

Mechanisms involved in the production of differently colored feathers in the structurally colored swallow tanager (Tersina viridis; Aves: Thraupidae).

Non-iridescent, structural coloration in birds originates from the feather's internal nanostructure (the spongy matrix) but melanin pigments and the barb's cortex can affect the resulting color. Here, we explore how this nanostructure is combined with other elements in differently colored plumage patches within a bird. We investigated the association between light reflectance and the morphology of feathers from the back and belly plumage patches of male swallow tanagers (Tersina viridis), which look greenish-blue and white, respectively. Both plumage patches have a reflectance peak around 550 nm but the reflectance spectrum is much less saturated in the belly. The barbs of both types of feathers have similar spongy matrices at their tips, rendering their reflectance spectra alike. However, the color of the belly feather barbs changes from light green at their tips to white closer to the rachis. These barbs lack pigments and their morphology changes considerably throughout. Toward the rachis, the barb is almost hollow, with a reduced area occupied by spongy matrix, and has a flattened shape. By contrast, the blue back feathers' barbs have melanin underneath the spongy matrix resulting in a much more saturated coloration. The color of these barbs is also even along the barbs' length. Our results suggest that the color differences between the white and greenish-blue plumage are mostly due to the differential deposition of melanin and a reduction of the spongy matrix near the rachis of the belly feather barbs and not a result of changes in the characteristics of the spongy matrix.

Determinants of mortality in patients with cirrhosis and uncontrolled variceal bleeding.

BACKGROUND & AIMS: Failure to control oesophago-gastric variceal bleeding (OGVB) and acute-on-chronic liver failure (ACLF) are both important prognostic factors in cirrhosis. The aims of this study were to determine whether ACLF and its severity define the risk of death in OGVB and whether insertion of rescue transjugular intrahepatic shunt (TIPS) improves survival in patients with failure to control OGVB and ACLF. METHODS: Data on 174 consecutive eligible patients, with failure to control OGVB between 2005 and 2015, were collected from a prospectively maintained intensive care unit registry. Rescue TIPS was defined as technically successful TIPS within 72 hours of presentation with failure to control OGVB. Cox-proportional hazards regression analyses were applied to explore the impact of ACLF and TIPS on survival in patients with failure to control OGVB. RESULTS: Patients with ACLF (n = 119) were significantly older, had organ failures and higher white cell count than patients with acute decompensation (AD, n = 55). Mortality at 42-days and 1-year was significantly higher in patients with ACLF (47.9% and 61.3%) than in those with AD (9.1% and 12.7%, p <0.001), whereas there was no difference in the number of endoscopies and transfusion requirements between these groups. TIPS was inserted in 78 patients (AD 21 [38.2%]; ACLF 57 [47.8%]; p = 0.41). In ACLF, rescue TIPS insertion was an independent favourable prognostic factor for 42-day mortality. In contrast, rescue TIPS did not impact on the outcome of patients with AD. CONCLUSIONS: This study shows that in patients with failure to control OGVB, the presence and severity of ACLF determines the risk of 42-day and 1-year mortality. Rescue TIPS is associated with improved survival in patients with ACLF. LAY SUMMARY: Variceal bleeding that is not controlled by initial endoscopy is associated with high risk of death. The results of this study showed that in the occurrence of failure of the liver and other organs defines the risk of death. In these patients, insertion of a shunt inside the liver to drain the portal vein improves survival.

Theoretical approaches to study the optical response of the red-legged honeycreeper's plumage (Cyanerpes cyaneus).

In this paper, we investigate the unusual color effect exhibited by the plumage of the heads of Cyanerpes cyaneus males, whose color turns from green to turquoise as the angle between the illumination and observation directions is increased. This singular color effect is characteristic of species that have quasi-ordered nanostructures of short-range order within the feather barbs. However, among species of the same family and even within feather patches of the same individual, one can find barbs with different characteristics, both macroscopic (curvature, shape, cross-sectional area) and in their internal microstructure. We apply the Korringa-Kohn-Rostoker method with the averaging technique to model the reflectance spectra for different angles of incidence and explain the dependence of the observed color with the incidence-collection angle. To investigate the influence of the disorder in the optical response of the spongy matrix, we apply the integral method for a two-dimensional cylinder system that simulates the distribution of air cavities within the $ \beta $ß-keratin medium. The experimental reflectance was interpreted as the result of multiple reflections in the internal interfaces generated by large air voids present within the spongy matrix. The application of rigorous methods to the study of natural photonic structures is of fundamental relevance for the design of efficient bioinspired artificial materials.

Evolution between forest macrorefugia is linked to discordance between genetic and morphological variation in Neotropical passerines.

The central Andean rainforests and the Atlantic Forest are two similar biomes that are fully isolated by xerophytic and open-vegetation regions (the Chaco and Cerrado, respectively). Even though there is evidence suggesting that these rainforests have been connected in the past, their dynamics of connection, the geographic areas that bridged these regions, and the biological processes that have promoted diversification between them remain to be studied. In this research, we used three passerine species (Poecilotriccus plumbeiceps, Phylloscartes ventralis and Cacicus chrysopterus) as models to address whether the Andean and the Atlantic forests have acted as a refugia system (macrorefugia), and to evaluate biogeographic hypotheses of diversification and connection between them. In order to achieve these goals, we performed traditional phylogeographic analyses and compared alternative biogeographic scenarios by using Approximate Bayesian Computation. Additionally, we performed morphological analyses to evaluate phenotypic divergence between these regions. Our findings support that both rainforest regions acted as refugia, but that the impact of their isolation was stronger on the genetic than on the morphologic characters. Our results provided evidence that both geographic isolation as well as ecological factors have modeled the external traits of forest organisms in the region. Regarding the connection routes between the Andes and the Atlantic Forest, the genetic data rejected the hypothesis of a Chaco connection in the tested species, providing evidence for a connection through the Cerrado or through the transition between the Cerrado and Chaco, in a process that could have started as early as the Late Miocene.

Carcinoembryonic antigen carrying SLeX as a new biomarker of more aggressive gastric carcinomas.

Malignant transformation of gastric cells is accompanied by the deregulated expression of glycosyltransferases leading to the biosynthesis of tumor-associated glycans such as the sialyl-Lewis X antigen (SLex). SLex presence on cell surface glycoconjugates increases the invasive capacity of gastric cancer cells and is associated with tumor metastasis. ST3Gal IV enzyme is involved in the synthesis of SLex antigen and overexpressed in gastric carcinomas. Herein, we identified the glycoproteins carrying SLex in gastric cancer cells overexpressing ST3Gal IV enzyme and evaluated their biomarker potential for gastric carcinoma. Methods: SLex modified glycoproteins were identified applying western blot and mass spectrometry. Immunoprecipitation, proximity ligation assay (PLA), E-selectin binding assay and CRISPR/cas9 knockout experiments were performed to characterize the presence of SLex on the identified glycoprotein. Protein N-glycans of the SLex protein carrier were in deep analyzed by porous-graphitized-carbon liquid-chromatography and tandem mass spectrometry glycomics. In silico expression analysis of α2-3 sialyltransferase ST3Gal IV and SLex protein carrier was performed and the conjoint expression of the SLex modified glycoproteins evaluated by immunohistochemistry and PLA in a series of gastric carcinomas. Results: Carcinoembryonic antigen (CEA; CEACAM5) was identified and validated by different methodologies as a major carrier of SLex. N-glycomics of CEA revealed that complex N-glycans are capped with α2-3 linked sialic acid (Neu5Acα2-3Galß1-4GlcNAc). Data set analysis of ST3Gal IV and CEA showed that ST3Gal IV expression was associated with patient´s poor survival, whereas CEA did not show any prognostic value. The co-expression of both CEA and SLeX was observed in 86,3% of gastric carcinoma cases and 74,5% of the total cases displayed the conjoint CEA+SLexin situ PLA expression. This expression was associated with clinicopathological features of the tumors, including infiltrative pattern of tumor growth, presence of venous invasion and patient's poor survival. CEA immunoprecipitation from gastric carcinoma tissues also confirmed the presence of SLex. Conclusion: CEA is the major glycoprotein carrying SLex in gastric carcinoma and the conjoint detection of CEA-SLex is associated with aggressive tumor features highlighting its PLA detection as a biomarker of gastric cancer patient prognosis for theranostic applications.

Contrasting evolutionary histories in Neotropical birds: Divergence across an environmental barrier in South America.

Avian diversity in the Neotropics has been traditionally attributed to the effect of vicariant forces promoting speciation in allopatry. Recent studies have shown that phylogeographical patterns shared among codistributed species cannot be explained by a single vicariant event, as species responses to a common barrier depend on the biological attributes of each taxon. The open vegetation corridor (OVC) isolates Amazonia and the Andean forests from the Atlantic Forest, creating a notorious pattern of avian taxa that are disjunctly codistributed in these forests. Here, we studied and compared the evolutionary histories of Ramphotrigon megacephalum and Pipraeidea melanonota, two passerines with allopatric populations east and west of the OVC that represent different subspecies. These species differ in their biological attributes: R. megacephalum is a sedentary, forest specialist mostly confined to bamboo understorey, whereas P. melanonota is a seasonal migrant and generalist species that ranges in a variety of closed and semi-open environments. We performed genetic and genomic analyses, complemented with the study of coloration and behavioural differentiation, to assess population divergence across the OVC. We found that the evolutionary histories of both R. megacephalum and P. melanonota have been shaped by this environmental barrier. However, these species responded in different and asynchronous manners to the establishment of the OVC and to past connections between the currently isolated South American forests, which can be mostly explained by their distinct ecologies and dispersal abilities. Our results support the fact that the biological attributes of species can make their evolutionary histories idiosyncratic.