Search

Severe COVID-19 is associated with epithelial and endothelial barrier dysfunction, however, the molecular pathways resulting in endothelial barrier dysfunction and vascular leakage are only sparsely understood. Here, Biering et al. show that SARS-CoV-2 spike protein is sufficient to induce barrier dysfunction and vascular leak. They show a role for integrins, TGF-beta, ECM remodeling enzymes, and glycosaminoglycans in this S-mediated barrier dysfunction.

Abstract Experimental vaccines for the deadly zoonotic Nipah (NiV), Hendra (HeV), and Ebola (EBOV) viruses have focused on targeting individual viruses, although their geographical and bat reservoir host overlaps warrant creation of multivalent vaccines. Here we explored whether replication-incompetent pseudotyped vesicular stomatitis virus (VSV) virions or NiV-based virus-like particles (VLPs) were suitable multivalent vaccine platforms by co-incorporating multiple surface glycoproteins from NiV, HeV, and EBOV onto these virions. We then enhanced the vaccines’ thermotolerance using carbohydrates to enhance applicability in global regions that lack cold-chain infrastructure. Excitingly, in a Syrian hamster model of disease, the VSV multivalent vaccine elicited safe, strong, and protective neutralizing antibody responses against challenge with NiV, HeV, or EBOV. Our study provides proof-of-principle evidence that replication-incompetent multivalent viral particle vaccines are sufficient to provide protection against multiple zoonotic deadly viruses with high pandemic potential.

ABSTRACT The Paramyxoviridae family comprises important pathogens that include measles (MeV), mumps, parainfluenza, and the emerging deadly zoonotic Nipah virus (NiV) and Hendra virus (HeV). Paramyxoviral entry into cells requires viral-cell membrane fusion, and formation of paramyxoviral pathognomonic syncytia requires cell-cell membrane fusion. Both events are coordinated by intricate interactions between the tetrameric attachment (G/H/HN) and trimeric fusion (F) glycoproteins. We report that receptor binding induces conformational changes in NiV G that expose its stalk domain, which triggers F through a cascade from prefusion to prehairpin intermediate (PHI) to postfusion conformations, executing membrane fusion. To decipher how the NiV G stalk may trigger F, we introduced cysteines along the G stalk to increase tetrameric strength and restrict stalk mobility. While most point mutants displayed near-wild-type levels of cell surface expression and receptor binding, most yielded increased NiV G oligomeric strength, and showed remarkably strong defects in syncytium formation. Furthermore, most of these mutants displayed stronger F/G interactions and significant defects in their ability to trigger F, indicating that NiV G stalk mobility is key to proper F triggering via moderate G/F interactions. Also remarkably, a mutant capable of triggering F and of fusion pore formation yielded little syncytium formation, implicating G or G/F interactions in a late step occurring post fusion pore formation, such as the extensive fusion pore expansion required for syncytium formation. This study uncovers novel mechanisms by which the G stalk and its oligomerization/mobility affect G/F interactions, the triggering of F, and a late fusion pore expansion step—exciting novel findings for paramyxoviral attachment glycoproteins. IMPORTANCE The important Paramyxoviridae family includes measles, mumps, human parainfluenza, and the emerging deadly zoonotic Nipah virus (NiV) and Hendra virus (HeV). The deadly emerging NiV can cause neurologic and respiratory symptoms in humans with a >60% mortality rate. NiV has two surface proteins, the receptor binding protein (G) and fusion (F) glycoproteins. They mediate the required membrane fusion during viral entry into host cells and during syncytium formation, a hallmark of paramyxoviral and NiV infections. We previously discovered that the G stalk domain is important for triggering F (via largely unknown mechanisms) to induce membrane fusion. Here, we uncovered new roles and mechanisms by which the G stalk and its mobility modulate the triggering of F and also unexpectedly affect a very late step in membrane fusion, namely fusion pore expansion. Importantly, these novel findings may extend to other paramyxoviruses, offering new potential targets for therapeutic interventions.

ABSTRACT Classified as a biosafety level 4 (BSL4) select agent, Nipah virus (NiV) is a deadly henipavirus in the Paramyxoviridae family, with a nearly 75% mortality rate in humans, underscoring its global and animal health importance. Elucidating the process of viral particle production in host cells is imperative both for targeted drug design and viral particle-based vaccine development. However, little is understood concerning the functions of cellular machinery in paramyxoviral and henipaviral assembly and budding. Recent studies showed evidence for the involvement of multiple NiV proteins in viral particle formation, in contrast to the mechanisms understood for several paramyxoviruses as being reliant on the matrix (M) protein alone. Further, the levels and purposes of cellular factor incorporation into viral particles are largely unexplored for the paramyxoviruses. To better understand the involvement of cellular machinery and the major structural viral fusion (F), attachment (G), and matrix (M) proteins, we performed proteomics analyses on virus-like particles (VLPs) produced from several combinations of these NiV proteins. Our findings indicate that NiV VLPs incorporate vesicular trafficking and actin cytoskeletal factors. The involvement of these biological processes was validated by experiments indicating that the perturbation of key factors in these cellular processes substantially modulated viral particle formation. These effects were most impacted for NiV-F-modulated viral particle formation either autonomously or in combination with other NiV proteins, indicating that NiV-F budding relies heavily on these cellular processes. These findings indicate a significant involvement of the NiV fusion protein, vesicular trafficking, and actin cytoskeletal processes in efficient viral particle formation. IMPORTANCE Nipah virus is a zoonotic biosafety level 4 agent with high mortality rates in humans. The genus to which Nipah virus belongs, Henipavirus, includes five officially recognized pathogens; however, over 20 species have been identified in multiple continents within the last several years. As there are still no vaccines or treatments for NiV infection, elucidating its process of viral particle production is imperative both for targeted drug design as well as for particle-based vaccine development. Developments in high-throughput technologies make proteomic analysis of isolated viral particles a highly insightful approach to understanding the life cycle of pathogens such as Nipah virus.

This study aimed to determine the effect of age on the immune and visceral organ weights and cecal traits in modern broilers. 200 male Ross® 308 broilers were randomly selected, then 20 broilers were slaughtered every day (up to 10 days old) after six hours of fasting. All the organs measured had a progressive increase in absolute weight as the days progressed, apart from the spleen, which decreased its absolute weight on day 5, even though on day 10 it showed the highest values. Moreover, the small intestine relative weight increased from the fourth to the ninth day and was correlated (p ≤ 0.05) with the relative weight of the proventriculus, gizzard, small intestine, and cecum, although without statistical association with the of the heart. There was a correlation between the cecum relative weight and the cecal lactic acid bacteria, and between the primary lymphoid organs. The pH (from 5.74 to 7.40) and cecal lactic acid bacteria (from 6.11 to 8.79 log 10 CFU/g) changed according to the age of the broilers. The results could contribute to the understanding of the physiology and intestinal microbiology of the first 10 days old of modern broilers, which is crucial to improve the genetic expression of these animals.

Feline morbillivirus (FeMV) was first isolated in stray cats in Hong Kong in 2012. Since its discovery, the virus has been reported in domestic cats worldwide, including in Hong Kong, Japan, Italy, US, Brazil, Turkey, UK, Germany, and Malaysia. FeMV is classified in the Morbillivirus genus within the Paramyxoviridae family. FeMV research has focused primarily on determining the host range, symptoms, and characteristics of persistent infections in vitro. Importantly, there is a potential association between FeMV infection and feline kidney diseases, such as tubulointerstitial nephritis (TIN) and chronic kidney diseases (CKD), which are known to significantly affect feline health and survival. However, the tropism and viral entry mechanism(s) of FeMV remain unknown. In this review, we summarize the FeMV studies up to date, including the discoveries of various FeMV strains, basic virology, pathogenicity, and disease signs.

El propósito fue determinar la relación entre el estado nutricional de la madre y las características de gestación del recién nacido de un grupo de embarazadas con diabetes gestacional. Se estudiaron 149 mujeres con diabetes gestacional de la Unidad de Alto Riesgo Obstétrico del Consultorio de Especialidades y Maternidad del Hospital Clínico Herminda Martin de Chillán, Chile, cuyos hijos nacieron en el año 2010. Los datos se obtuvieron de la historia clínica perinatal y la ficha del recién nacido. Las variables registradas en la madre fueron estado nutricional, vía de parto, número de gestaciones, control metabólico de la diabetes gestacional. Del niño se obtuvo el peso, circunferencia craneana y diagnóstico gestacional. Los datos fueron estudiados mediante análisis descriptivo univariado, bivariado y multivariado, ANOVA de un factor, Chi cuadrado y análisis de correspondencia múltiple. Se encontró que las mujeres con estado nutricional normal, eran multigestas, tuvieron parto vaginal, su hijo recién nacido fue adecuado para la edad gestacional, normocefálico;por otro lado, la condición de obesidad materna se relacionó con partos por cesárea, recién nacidos grandes para edad gestacional y macrocefalia; las mujeres con sobrepeso en general fueron primigestas y el recién nacido pequeño para edad gestacional con microcefalia p

Objective: The objective of this study was to analyze the evolution in the diagnosis and management of indeterminate thyroid nodules over three time periods. Methods: In total, 3020 patients with thyroid nodules underwent cytological evaluation during three periods (2006– 2008, 2012–2014, 2017–2019). The distribution of diagnostic cytology, risk of malignancy, diagnostic performance indices of fine needle aspiration (FNA), and cytologic–histologic correlation in indeterminate cytology were analyzed. Results: Only 2.2% of cytology tests were insufficient for a diagnosis. About 86.9% cytology was benign, 1.7% malignant, and 11.4% indeterminate. Indeterminate cytology rates were 15.9% (2006–2008), 10.1% (2012–2014), and 10% (2017–2019). Surgery was performed in 13% of benign cytology, resulting in malignant histology in 2.7%. All malignant and suspicious cytology underwent surgery, with malignancy confirmed in 98% and 77% of cases, respectively. All ‘indeterminate with atypia’ cytology (2006–2008) and Bethesda IV (2012–2014; 2017–2019) underwent surgery, with malignancy confirmed in 19.6%, 43.8%, and 25.7%, respectively. In the ‘indeterminate without atypia’ category (2006–2008) and Bethesda III (2012–2014; 2017–2019), diagnostic surgery was performed in 57.7%, 78.6%, and 59.4%, respectively, with malignancy confirmed in 3.3%, 20.5%, and 31.6%. The FNA sensitivity was 91.6%, with a negative predictive value greater than 96% in all periods. The specificity exceeded 75% in the last two periods. Conclusion: The Bethesda system reduces indeterminate cytology and improves the accuracy of FNA diagnosis. We reported a higher proportion of malignancy than expected in Bethesda III, underscoring the importance of having institution-specific data to guide decision-making. However, there is a need for risk stratification tools that allow for conservative management in low-risk cases.

En este artículo se presentan avances de una investigación en desarrollo que analiza las relaciones entre la participación de mujeres rurales en iniciativas productivas de tipo asociativo y sus posibles procesos de empoderamiento en contextos interculturales. En específico, se exploran los efectos que tienen este tipo de iniciativas en la vida de las mujeres rurales de la Región de la Araucanía, explorando si a partir de su participación colectiva se producen procesos de toma de conciencia respecto de la subordinación de género y si se promueven cambios que favorezcan relaciones más equitativas para las mujeres. Bajo el diseño de la teoría fundamentada con perspectiva construccionista, se realizaron diez registros de observaciones participantes y un taller de discusión con mujeres socias de un emprendimiento de tipo productivo. Las conclusiones muestran el empoderamiento de las mujeres rurales como un proceso en el cual ellas pueden pasar por múltiples y paradójicos momentos tanto de desempoderamiento como de empoderamiento, los cuales coexisten, se suceden o se superponen entre sí.

Abstract Background The main objective of this research was to analyze the characteristics of electrical activity in the brain during REM (Rapid Eye Movements) sleep, by using an experimental model a pathology that affects the frontal lobes, such as brain tumors. In addition to determining the impact of variables such as the frontal area (dorsolateral, medial and orbital), laterality and size of the lesion; as well as the demographic and clinical characteristics of the patients evaluated. Methods By using polysomnographic recordings, 10 patients were evaluated. We obtained power spectra through a homemade program. For quantitative EEG (Electroencephalogram) (qEEG) analysis, the Fast Fourier Transform (FFT) algorithm was used to obtain the spectral power of each participant, channel, and frequency band. Results Sleep architecture and spectral power was found to be modified in patients compared to normative values. Other sociodemographic and clinical characteristics of the patients were also influenced, such as age range and antiepileptic drugs. Conclusions Brain tumors in the frontal lobe can modify the rhythmogenesis of REM sleep, possibly due to changes of brain plasticity as an effect of the pathology. In addition to this, through this study we were able to show the association between neuroanatomical and functional changes, on the characteristics of brain electrical activity in patients with frontal brain tumor. Finally, this qEEG analysis technique allows, on the one hand, to deepen the knowledge and relationship between psychophysiological processes and, on the other hand, to be able to guide therapeutic decisions.

Abstract Background Cutaneous forms of leishmaniosis due to Leishmania braziliensis have been reported in horses in the New World. Domestic animals play a role in the transmission of the disease. In Costa Rica, human cases of L. braziliensis, L. panamensis and L. infantum have been reported. Objectives The present report describes five cases of equine cutaneous leishmaniosis in Costa Rica. The aetiological diagnosis was based on the presence of the parasite within the lesions. Methods Skin biopsies were used to perform histopathological analyses of the lesions. Immunohistochemistry was used to detect the presence of the Leishmania spp. antigens in tissue sections. Laser‐capture micro‐dissection and quantitative real‐time PCR techniques were carried out to detect the pathogen nucleic acid within the microscopic lesions. Results Histopathological analyses showed a granulomatous inflammation within the dermis, with multi‐nucleated giant cells, macrophages, lymphocytes and few neutrophils and eosinophils. We detected the parasite by immunohistochemistry, using a rabbit polyclonal antibody raised against Leishmania spp. However, we could not identify Leishmania spp. by quantitative real‐time PCR in formalin‐fixed paraffin‐embedded tissues, using specific primers for the conserved region in the minicircle of the Leishmania DNA kinetoplast. Conclusions Our results emphasise the importance of Leishmania spp. not only as a causative agent of equine cutaneous disease in the New World, but also as a possible emerging pathogen. Leishmaniosis is one of the most prevalent parasitic public health problems worldwide, and equines may have a role in the epidemiology of the disease.

Background: Double blockade with pertuzumab and trastuzumab combined with chemotherapy is the standard neoadjuvant treatment for HER2-positive early breast cancer. Data derived from clinical trials indicates that the response rates differ among intrinsic subtypes of breast cancer. The aim of this study is to determine if these results are valid in real-world patients.Methods: A total of 259 patients treated in eight Spanish hospitals were included and divided into two cohorts: Cohort A (132 patients) received trastuzumab plus standard neoadjuvant chemotherapy (NAC), and Cohort B received pertuzumab and trastuzumab plus NAC (122 patients). Pathological complete response (pCR) was defined as the complete disappearance of invasive tumor cells. Assignment of the intrinsic subtype was realized using the research-based PAM50 signature.Results: There were more HER2-enriched tumors in Cohort A (70 vs. 56%) and more basal-like tumors in Cohort B (12 vs. 2%), with similar luminal cases in both cohorts (luminal A 12 vs. 14%; luminal B 14 vs. 18%). The overall pCR rate was 39% in Cohort A and 61% in Cohort B. Better pCR rates with pertuzumab plus trastuzumab than with trastuzumab alone were also observed in all intrinsic subtypes (luminal PAM50 41 vs. 11.4% and HER2-enriched subtype 73.5 vs. 50%) but not in basal-like tumors (53.3 vs. 50%). In multivariate analysis the only significant variables related to pCR in both luminal PAM50 and HER2-enriched subtypes were treatment with pertuzumab plus trastuzumab (Cohort B) and histological grade 3.Conclusions: With data obtained from patients treated in clinical practice, it has been possible to verify that the addition of pertuzumab to trastuzumab and neoadjuvant chemotherapy substantially increases the rate of pCR, especially in the HER2-enriched subtype but also in luminal subtypes, with no apparent benefit in basal-like tumors.

This article presents the progress of a major research whose objective is to analyze the relationships between the participation of women in rural areas in associative economic and productive initiatives and their potential empowerment processes in intercultural contexts. Specifically, this work explores the processes of subordination awareness, transformation of gender roles and the construction of their positioning as social actors by participants of economic and productive associations from La Araucanía Region. Following the constructionist Grounded Theory perspective, ten notes of participant observations and a workshop of discussion were implemented with women associated with each other to develop this kind of enterprises. The conclusions show the empowerment of women in rural areas as a process in which they can go through multiple and paradoxical moments, both empowerment and disempowerment, which coexist, occur after one another or overlap