Isolation of Diverse Simian Arteriviruses Causing Hemorrhagic Disease.

Genetically diverse simian arteriviruses (simarteriviruses) naturally infect geographically and phylogenetically diverse monkeys, and cross-species transmission and emergence are of considerable concern. Characterization of most simarteriviruses beyond sequence analysis has not been possible because the viruses fail to propagate in the laboratory. We attempted to isolate 4 simarteriviruses, Kibale red colobus virus 1, Pebjah virus, simian hemorrhagic fever virus, and Southwest baboon virus 1, by inoculating an immortalized grivet cell line (known to replicate simian hemorrhagic fever virus), primary macaque cells, macrophages derived from macaque induced pluripotent stem cells, and mice engrafted with macaque CD34+-enriched hematopoietic stem cells. The combined effort resulted in successful virus isolation; however, no single approach was successful for all 4 simarteriviruses. We describe several approaches that might be used to isolate additional simarteriviruses for phenotypic characterization. Our results will expedite laboratory studies of simarteriviruses to elucidate virus-host interactions, assess zoonotic risk, and develop medical countermeasures.

Cotyledon-Specific Flow Evaluation of Rhesus Macaque Placental Injury Using Ferumoxytol Dynamic Contrast-Enhanced MRI.

BACKGROUND: Recently, dynamic contrast-enhanced (DCE) MRI with ferumoxytol as contrast agent has recently been introduced for the noninvasive assessment of placental structure and function throughout. However, it has not been demonstrated under pathological conditions. PURPOSE: To measure cotyledon-specific rhesus macaque maternal placental blood flow using ferumoxytol DCE MRI in a novel animal model for local placental injury. STUDY TYPE: Prospective animal model. SUBJECTS: Placental injections of Tisseel (three with 0.5 mL and two with 1.5 mL), monocyte chemoattractant protein 1 (three with 100 µg), and three with saline as controls were performed in a total of 11 rhesus macaque pregnancies at approximate gestational day (GD 101). DCE MRI scans were performed prior (GD 100) and after (GD 115 and GD 145) the injection (term = GD 165). FIELD STRENGTH/SEQUENCE: 3 T, T1-weighted spoiled gradient echo sequence (product sequence, DISCO). ASSESSMENT: Source images were inspected for motion artefacts from the mother or fetus. Placenta segmentation and DCE processing were performed for the dynamic image series to measure cotyledon specific volume, flow, and normalized flow. Overall placental histopathology was conducted for controls, Tisseel, and MCP-1 animals and regions of tissue infarctions and necrosis were documented. Visual inspections for potential necrotic tissue were conducted for the two Tisseelx3 animals. STATISTICAL TESTS: Wilcoxon rank sum test, significance level P < 0.05. RESULTS: No motion artefacts were observed. For the group treated with 1.5 mL of Tisseel, significantly lower cotyledon volume, flow, and normalized flow per cotyledon were observed for the third gestational time point of imaging (day ~145), with mean normalized flow of 0.53 minute-1 . Preliminary histopathological analysis shows areas of tissue necrosis from a selected cotyledon in one Tisseel-treated (single dose) animal and both Tisseelx3 (triple dose) animals. DATA CONCLUSION: This study demonstrates the feasibility of cotyledon-specific functional analysis at multiple gestational time points and injury detection in a placental rhesus macaque model through ferumoxytol-enhanced DCE MRI. LEVEL OF EVIDENCE: NA TECHNICAL EFFICACY: Stage 2.

Listeria monocytogenes infection in pregnant macaques alters the maternal gut microbiome†.

OBJECTIVES: The bacterium Listeria monocytogenes (Lm) is associated with adverse pregnancy outcomes. Infection occurs through consumption of contaminated food that is disseminated to the maternal-fetal interface. The influence on the gastrointestinal microbiome during Lm infection remains unexplored in pregnancy. The objective of this study was to determine the impact of listeriosis on the gut microbiota of pregnant macaques. METHODS: A non-human primate model of listeriosis in pregnancy has been previously described. Both pregnant and non-pregnant cynomolgus macaques were inoculated with Lm and bacteremia and fecal shedding were monitored for 14 days. Non-pregnant animal tissues were collected at necropsy to determine bacterial burden, and fecal samples from both pregnant and non-pregnant animals were evaluated by 16S rRNA next-generation sequencing. RESULTS: Unlike pregnant macaques, non-pregnant macaques did not exhibit bacteremia, fecal shedding, or tissue colonization by Lm. Dispersion of Lm during pregnancy was associated with a significant decrease in alpha diversity of the host gut microbiome, compared to non-pregnant counterparts. The combined effects of pregnancy and listeriosis were associated with a significant loss in microbial richness, although there were increases in some genera and decreases in others. CONCLUSIONS: Although pregnancy alone is not associated with gut microbiome disruption, we observed dysbiosis with listeriosis during pregnancy. The macaque model may provide an understanding of the roles that pregnancy and the gut microbiota play in the ability of Lm to establish intestinal infection and disseminate throughout the host, thereby contributing to adverse pregnancy outcomes and risk to the developing fetus.

Concordance and reproducibility in the location of reference points for a volumetric craniofacial analysis: Cross-sectional study.

Background: Considering the limitations of visualization that occur even with the use of radiographs, the cone beam computed tomography (CBCT) becomes more attractive to diagnose and propose an assertive treatment plan. This study aimed to evaluate intra and interobserver reproducibility, and concordance of 31 reference points we described considering visualization tools and the three planes of space in a bimaxillary CBCT. Methods: Three observers located in triplicate the 31 reference points in the CBCT of six healthy patients. Friedman test was used to compare intraobserver paired samples, and interobserver concordance was determined by the intraclass correlation coefficient (ICC) with ranges>0.75 (excellent), between 0.60 and 0.74 (good), between 0.40 and 0.59 (sufficient) and<0.40 (poor). The P value was set at<0.05. Results: A high ICC (>0.75%) was obtained by comparing the x, y, and z values at the location of landmark points. Excellent ICC>0.75 was for 81.7% and poor<0.40 was 7.5% in the interobserver evaluation. Data showed that 25 points had excellent concordance on the x-plane, 25 on the y-plane, and 26 on the z-plane (0.75%). Conclusion: Intraobserver concordance analysis indicated that location of anatomical reference points on bimaxillary CBCT is performed with great reproducibility by interpreting their location with a clear description in the three planes of space. Complexity of achieving a good precision degree in the manual marking of reference points caused by convexities of the anatomical structures involved, might explain the variability found. The systematized location of the reference points would contribute to reduce such variability.

Infection of the maternal-fetal interface and vertical transmission following low-dose inoculation of pregnant rhesus macaques (Macaca mulatta) with an African-lineage Zika virus.

BACKGROUND: Congenital Zika virus (ZIKV) infection can result in birth defects, including malformations in the fetal brain and visual system. There are two distinct genetic lineages of ZIKV: African and Asian. Asian-lineage ZIKVs have been associated with adverse pregnancy outcomes in humans; however, recent evidence from experimental models suggests that African-lineage viruses can also be vertically transmitted and cause fetal harm. METHODOLOGY/PRINCIPAL FINDINGS: To evaluate the pathway of vertical transmission of African-lineage ZIKV, we inoculated nine pregnant rhesus macaques (Macaca mulatta) subcutaneously with 44 plaque-forming units of a ZIKV strain from Senegal, (ZIKV-DAK). Dams were inoculated either at gestational day 30 or 45. Following maternal inoculation, pregnancies were surgically terminated seven or 14 days later and fetal and maternal-fetal interface tissues were collected and evaluated. Infection in the dams was evaluated via plasma viremia and neutralizing antibody titers pre- and post- ZIKV inoculation. All dams became productively infected and developed strong neutralizing antibody responses. ZIKV RNA was detected in maternal-fetal interface tissues (placenta, decidua, and fetal membranes) by RT-qPCR and in situ hybridization. In situ hybridization detected ZIKV predominantly in the decidua and revealed that the fetal membranes may play a role in ZIKV vertical transmission. Infectious ZIKV was detected in the amniotic fluid of three pregnancies and one fetus had ZIKV RNA detected in multiple tissues. No significant pathology was observed in any fetus; and ZIKV did not have a substantial effect on the placenta. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that a very low dose of African-lineage ZIKV can be vertically transmitted to the macaque fetus during pregnancy. The low inoculating dose used in this study suggests a low minimal infectious dose for rhesus macaques. Vertical transmission with a low dose in macaques further supports the high epidemic potential of African ZIKV strains.

Frequent first-trimester pregnancy loss in rhesus macaques infected with African-lineage Zika virus.

In the 2016 Zika virus (ZIKV) pandemic, a previously unrecognized risk of birth defects surfaced in babies whose mothers were infected with Asian-lineage ZIKV during pregnancy. Less is known about the impacts of gestational African-lineage ZIKV infections. Given high human immunodeficiency virus (HIV) burdens in regions where African-lineage ZIKV circulates, we evaluated whether pregnant rhesus macaques infected with simian immunodeficiency virus (SIV) have a higher risk of African-lineage ZIKV-associated birth defects. Remarkably, in both SIV+ and SIV- animals, ZIKV infection early in the first trimester caused a high incidence (78%) of spontaneous pregnancy loss within 20 days. These findings suggest a significant risk for early pregnancy loss associated with African-lineage ZIKV infection and provide the first consistent ZIKV-associated phenotype in macaques for testing medical countermeasures.

Salud mental y COVID-19 en estudiantes de enfermería / Mental Health and COVID-19 in Nursing Students

Introducción: La salud mental de los estudiantes de enfermería en tiempos de COVID-19 ha tenido diversas afectaciones, lo que implica un desafío para la formación. Por ser un tema emergente, es necesario integrar en una perspectiva unitaria los estudios más relevantes, para vislumbrar los impactos inmediatos de la pandemia y las acciones que se han emprendido. Objetivo: Analizar la evidencia científica disponible sobre la salud mental de estudiantes de enfermería en el contexto de la pandemia por COVID-19. Métodos: Revisión integrativa realizada durante febrero y marzo de 2021, en las bases de datos Scopus, ScienceDirect, Lilacs, PubMed, CINHAL, Web of Science, SciELO y PsycINFO. La ecuación de búsqueda incluyó los términos Medical Subject Headings (MeSH): "Mental Health", "COVID-19" y "Students, Nursing", combinados con el operador booleano AND. Se evaluaron estudios primarios y secundarios con diferentes enfoques o metodologías en idioma español, inglés o portugués, con disponibilidad de texto completo, publicados hasta la fecha de revisión. Se excluyeron artículos de opinión y cartas al editor. De un total de 535 artículos, se incluyeron 25. Se realizó análisis de contenido cualitativo. Conclusiones: Se identificaron impactos inmediatos en las emociones, estados de ánimo y trastornos emocionales como ansiedad, estrés y depresión; todos ellos mediados por determinantes sociales, biológicos y psicológicos. Las acciones emprendidas están relacionadas con estrategias de afrontamiento y respuestas institucionales(AU)

Introduction: The mental health of nursing students in times of COVID-19 has had diverse issues, which implies a challenge for training. Being an emerging matter, it is necessary to integrate in a unitary perspective the most relevant studies, to glimpse the immediate impacts of the pandemic and the actions that have been undertaken. Objective: To analyze the available scientific evidence on the mental health of nursing students in the context of the COVID-19 pandemic. Methods: Integrative review conducted during February and March 2021 in the databases Scopus, ScienceDirect, Lilacs, PubMed, CINHAL, Web of Science, SciELO and PsycINFO. The search equation included the terms Medical Subject Headings (MeSH): "Mental Health", "COVID-19" and "Students, Nursing", combined with the Boolean operator AND. We evaluated primary and secondary studies with different approaches or methodologies in Spanish, English or Portuguese, with full text availability, published up to the review date. Opinion articles and letters to the editor were excluded. From a total of 535 articles, 25 were included. Qualitative content analysis was performed. Conclusions: Immediate impacts on emotions, mood states and emotional disorders such as anxiety, stress and depression were identified; all mediated by social, biological and psychological determinants. Actions taken are related to coping strategies and institutional responses(AU)

Prediction of Micellar Thermodynamics of Nonionic Surfactants Based on the Square Gradient Theory.

A geometry-dependent contribution based on the square gradient theory of van der Waals is proposed as a predictive modification of the interfacial energy contribution for the micellar thermodynamic theory. The model has an analytic prediction for the spherical and cylindrical geometries. For ellipsoidal geometry, a simple yet physically meaningful approximation is proposed. The critical micelle concentration (CMC) and the surface tension isotherm under the new contribution are compared with the classical theory. The modified model describes qualitatively the available experimental data and the surface isotherm, showing an improvement in the predictions of the CMC.

Fetal loss in pregnant rhesus macaques infected with high-dose African-lineage Zika virus.

Countermeasures against Zika virus (ZIKV), including vaccines, are frequently tested in nonhuman primates (NHP). Macaque models are important for understanding how ZIKV infections impact human pregnancy due to similarities in placental development. The lack of consistent adverse pregnancy outcomes in ZIKV-affected pregnancies poses a challenge in macaque studies where group sizes are often small (4-8 animals). Studies in small animal models suggest that African-lineage Zika viruses can cause more frequent and severe fetal outcomes. No adverse outcomes were observed in macaques exposed to 1x104 PFU (low dose) of African-lineage ZIKV at gestational day (GD) 45. Here, we exposed eight pregnant rhesus macaques to 1x108 PFU (high dose) of African-lineage ZIKV at GD 45 to test the hypothesis that adverse pregnancy outcomes are dose-dependent. Three of eight pregnancies ended prematurely with fetal death. ZIKV was detected in both fetal and placental tissues from all cases of early fetal loss. Further refinements of this exposure system (e.g., varying the dose and timing of infection) could lead to an even more consistent, unambiguous fetal loss phenotype for assessing ZIKV countermeasures in pregnancy. These data demonstrate that high-dose exposure to African-lineage ZIKV causes pregnancy loss in macaques and also suggest that ZIKV-induced first trimester pregnancy loss could be strain-specific.

Cistitis hemorrágica por adenovirus en trasplante renal: revisión epidemiológica y resultados clínicos

Contexto la infección de vías urinarias (IVU), causada por adenovirus (ADV) posterior al trasplante renal, tiene el potencial de causar disfunción o pérdida del injerto. La presentación clínica es variable y el tratamiento difiere según la disponibilidad de medicamentos en el medio y la experiencia clínica. Objetivo el estudio describe las características clínicas, de laboratorio y la respuesta al tratamiento de una serie de casos de pacientes trasplantados renales con IVU por ADV en un hospital de Cali, Colombia. Metodología estudio retrospectivo que incluye a todos los pacientes adultos trasplantados con diagnóstico de IVU por ADV entre enero del 2015 hasta enero del 2021. El diagnóstico se realizó basado en la clínica, el resultado positivo de la prueba de reacción de cadena de polimerasa (PCR) y la carga viral del ADV. Resultados de 256 pacientes trasplantados, ocho presentaron diagnóstico de cistitis hemorrágica o nefritis intersticial secundaria a infección por ADV. Se presentó de forma temprana (≤ 3 meses) en el 62 % de los casos, quienes debutaron con macrohematuria asociada a piuria estéril y linfopenia. Por otra parte, se presentó alteración en la función renal en el 87,5 % de los casos y la reducción de la inmunosupresión fue el pilar fundamental en el manejo clínico. Conclusiones el reconocimiento de la infección por ADV en pacientes trasplantados renales ha ido en aumento. La sospecha clínica es clave para el diagnóstico (macrohematuria, síntomas urinarios irritativos y falla renal) y la reducción de la dosis de inmunosupresión para restaurar la función inmune puede ser suficiente en la resolución de la infección y la reversión de la disfunción renal.

Introduction Urinary tract infection (UTI) caused by adenovirus (ADV) after kidney transplantation has the potential to cause graft dysfunction or loss. The clinical presentation is variable, from an asymptomatic course to a multisystemic compromise. Treatment varies based on the availability of different medications and clinical experience. Objective The study describe the clinical, laboratory characteristics and results of a series of cases of kidney transplant patients with hemorrhagic cystitis secondary to ADV infection in a hospital in Cali, Colombia. Methods Retrospective study based on the records of patients with a diagnosis of UTI caused by ADV between January 2015 to January 2021 were included. The diagnosis was made by clinical suspicion and polymerase chain reaction (PCR) - Adenovirus DNA viral load. Results Of 256 transplant patients, eight patients had a diagnosis of hemorrhagic cystitis or interstitial nephritis secondary to ADV infection. It presented early (≤ 3 months) in 62%, who presented with macrohematuria, associated with sterile pyuria and lymphopenia. Alterations in renal function were presented in 87.5%. The reduction of immunosuppression was the fundamental pillar in the management. Conclusions The recognition of ADV infection in kidney transplant patients has been increasing. Clinical suspicion is the key for the diagnosis, with a predominance of macrohematuria, irritative urinary symptoms and kidney graft dysfunction. Reducing the dose of immunosuppression by restoring immune function may be sufficient in resolving the infection and reversing renal dysfunction.

Compromiso renal atípico en amiloidosis de cadena ligera

Introducción la amiloidosis de cadena ligera (AL) es una entidad desencadenada por la proliferación de un clon de células plasmáticas que genera la acumulación de cadenas ligeras, las cuales se depositan en forma de fibrillas amiloides generando una disfunción orgánica. El compromiso renal generalmente se manifiesta como síndrome nefrótico, con un deterioro lento y progresivo de la función renal que puede llevar a un requerimiento de terapia dialítica. Objetivo demostrar el compromiso renal agresivo y subagudo de la amiloidosis sistémica. Presentación del caso paciente masculino de 35 años que consulta por malestar general, visión borrosa, mareos y oliguria con elevación de azoados, y que progresó rápidamente hasta el requerimiento de hemodiálisis en aproximadamente tres meses. Asociado se documenta polineuropatía periférica, infiltración cardiaca y ligera elevación de transaminasas. Ante negatividad de estudios de extensión, se logra documentar la presencia histopatológica de depósitos amiloides con inmunofluorescencia positiva para AL. Actualmente, se encuentra recibiendo esquema de quimioterapia con adecuada estabilidad clínica y tolerancia. Discusión y conclusión la amiloidosis AL es una entidad infrecuente, con compromiso multiorgánico importante y altas tasas de morbilidad y mortalidad. Se recalca en este caso el compromiso subagudo con requerimiento temprano de terapia dialítica y además se enfatiza la importancia de una sospecha y un diagnóstico oportuno en pacientes con compromiso renal y otras manifestaciones sistémicas.

Introduction Light chain amyloidosis is an entity triggered by the proliferation of a clone of plasma cells that generates the accumulation of light chains, which are deposited in the form of amyloid fibrils generating organic dysfunction. Renal compromise generally manifests as nephrotic syndrome, with a slow and progressive decline of renal function that can lead to dialysis therapy. Purpose The objective of this case report is to demonstrate the aggressive and subacute renal involvement of systemic amyloidosis. Case presentation We present a case of a 35-year-old male patient who consulted for general malaise, blurred vision, dizziness and oliguria with elevated nitrogen levels that progressed fastly to the requirement of hemodialysis in approximately 3 months. It was also reveal peripheral polyneuropathy, cardiac infiltration, and slight elevation of transaminases. Given the negativity of extension studies, amyloid deposits were documented histopathologically with positive immunofluorescence for LA. He is currently receiving chemotherapy regimen with adequate clinical stability and tolerance. Conclusion and discussion To conclude, AL amyloidosis is a rare entity, with significant multi-organ involvement and high rates of morbidity and mortality. In this case, the subacute involvement with an early requirement for dialysis therapy is emphasized, and the importance of suspicion and timely diagnosis in patients with kidney involvement and other systemic manifestations is emphasized.

Human immune globulin treatment controls Zika viremia in pregnant rhesus macaques.

There are currently no approved drugs to treat Zika virus (ZIKV) infection during pregnancy. Hyperimmune globulin products such as VARIZIG and WinRho are FDA-approved to treat conditions during pregnancy such as Varicella Zoster virus infection and Rh-incompatibility. We administered ZIKV-specific human immune globulin as a treatment in pregnant rhesus macaques one day after subcutaneous ZIKV infection. All animals controlled ZIKV viremia following the treatment and generated robust levels of anti-Zika virus antibodies in their blood. No adverse fetal or infant outcomes were identified in the treated animals, yet the placebo control treated animals also did not have signs related to congenital Zika syndrome (CZS). Human immune globulin may be a viable prophylaxis and treatment option for ZIKV infection during pregnancy, however, more studies are required to fully assess the impact of this treatment to prevent CZS.

Mild hypothermia fails to protect infant macaques from brain injury caused by prolonged exposure to Antiseizure drugs.

Barbiturates and benzodiazepines are GABAA-receptor agonists and potent antiseizure medications. We reported that exposure of neonatal macaques to combination of phenobarbital and midazolam (Pb/M) for 24 h, at clinically relevant doses and plasma levels, causes widespread apoptosis affecting neurons and oligodendrocytes. Notably, the extent of injury was markedly more severe compared to shorter (8 h) exposure to these drugs. We also reported that, in the infant macaque, mild hypothermia ameliorates the apoptosis response to the anesthetic sevoflurane. These findings prompted us explore whether mild hypothermia might protect infant nonhuman primates from neuro- and gliotoxicity of Pb/M. Since human infants with seizures may receive combinations of benzodiazepines and barbiturates for days, we opted for 24 h treatment with Pb/M. Neonatal rhesus monkeys received phenobarbital intravenously, followed by midazolam infusion over 24 h under normothermia (T > 36.5 °C-37.5 °C; n = 4) or mild hypothermia (T = 35 °C-36.5 °C; n = 5). Medication doses and blood levels measured were comparable to those in human infants. Animals were euthanized at 36 h and brains examined immunohistochemically and stereologically. Treatment was well tolerated. Extensive degeneration of neurons and oligodendrocytes was seen at 36 h in both groups within neocortex, basal ganglia, hippocampus and brainstem. Mild hypothermia over 36 h (maintained until terminal perfusion) conferred no protection against the neurotoxic and gliotoxic effects of Pb/M. This is in marked contrast to our previous findings that mild hypothermia is protective in the context of a 5 h-long exposure to sevoflurane in infant macaques. These findings demonstrate that brain injury caused by prolonged exposure to Pb/M in the neonatal primate cannot be ameliorated by mild hypothermia.

In Silico, In Vitro, and Pharmacokinetic Studies of UBMC-4, a Potential Novel Compound for Treating against Trypanosoma cruzi.

The lack of therapeutic alternatives for the treatment of Chagas disease, a neglected disease, drives the discovery of new drugs with trypanocidal activity. Consequently, we conducted in vitro studies using UBMC-4, a potential Trypanosoma cruzi AKT-like pleckstrin homology (PH) domain inhibitory compound found using bioinformatics tools. The half effective concentration (EC50) on intracellular amastigotes was determined at 1.85 ± 1 µM showing low cytotoxicity (LC50) > 40 µM on human cell lines tested. In order to study the lethal effect caused by the compound on epimastigotes, morphological changes were assessed by scanning and transmission electron microscopy. Progressive alterations such as flagellum inactivation, cell size reduction, nuclear structure alteration, condensation of chromatin towards the nuclear periphery, vacuole formation, and mitochondrial swelling with kinetoplast integrity loss were evidenced. In addition, apoptosis-like markers in T. cruzi were assessed by flow cytometry, demonstrating that the effect of UBMC-4 on T. cruzi AKT-like kinase reduced the tolerance to nutritional stress-triggered, apoptosis-like events, including DNA fragmentation, mitochondrial damage, and loss of plasma membrane integrity. After this, UBMC-4 was formulated for oral administration and pharmacokinetics were analyzed in a mouse model. Finally, upon oral administration of 200 mg/kg in mice, we found that a UBMC-4 plasma concentration remaining in circulation beyond 24 h after administration is well described by the two-compartment model. We conclude that UBMC-4 has an effective trypanocidal activity in vitro at low concentrations and this effect is evident in T. cruzi cell structures. In mice, UBMC-4 was well absorbed and reached plasma concentrations higher than the EC50, showing features that would aid in developing a new drug to treat Chagas disease.

Assessment of safety and immunogenicity of MHC homozygous iPSC-derived CD34+ hematopoietic progenitors in an NHP model.

Administration of ex vivo expanded somatic myeloid progenitors has been explored as a way to facilitate a more rapid myeloid recovery and improve overall survival after myeloablation. Recent advances in induced pluripotent stem cell (iPSC) technologies have created alternative platforms for supplying off-the-shelf immunologically compatible myeloid progenitors, including cellular products derived from major histocompatibility complex (MHC) homozygous superdonors, potentially increasing the availability of MHC-matching cells and maximizing the utility of stem cell banking. However, the teratogenic and tumorigenic potential of iPSC-derived progenitor cells and whether they will induce alloreactive antibodies upon transfer remain unclear. We evaluated the safety and efficacy of using CD34+CD45+ hematopoietic progenitors derived from MHC homozygous iPSCs (iHPs) to treat cytopenia after myeloablative hematopoietic stem cell (HSC) transplantation in a Mauritian cynomolgus macaque (MCM) nonhuman primate (NHP) model. We demonstrated that infusion of iHPs was well tolerated and safe, observing no teratomas or tumors in the MCMs up to 1 year after HSC transplantation and iHP infusion. Importantly, the iHPs also did not induce significant levels of alloantibodies in MHC-matched or -mismatched immunocompetent MCMs, even after increasing MHC expression on iHPs with interferon-γ. These results support the feasibility of iHP use in the setting of myeloablation and suggest that iHP products pose a low risk of inducing alloreactive antibodies.

Molecular dynamics of liquid-liquid equilibrium and interfacial properties of aqueous solutions of methyl esters.

In this work, the liquid-liquid phase equilibria and interfacial properties of methyl ester + water binary mixtures are determined at atmospheric pressure and from 278 to 358 K combining the direct coexistence technique and molecular dynamics simulations. Methyl esters are modelled using new parametrizations based on the united atom TraPPE model force field proposed recently by us [E. Feria, J. Algaba, J. M. Míguez, A. Mejía, P. Gómez-Álvarez and F. J. Blas, Phys. Chem. Chem. Phys., 2019, 22, 4974-4983] that are able to predict the vapour-liquid interfacial properties of pure methyl esters with high accuracy. In the case of water, we consider the well-known TIP4P/2005 model, the most popular rigid and non-polarizable model to describe the interfacial properties of pure water. The simulations are performed using the direct coexistence technique in the isothermal-isobaric or NPzT ensemble in combination with molecular dynamics. We obtain density profiles, temperature-densities and temperature-composition projections of the phase diagrams, and interfacial tensions. The liquid-liquid interfacial tension is calculated from the normal and tangential components of the pressure tensor according to the mechanical virial route. We pay attention particularly to the ability of the molecular models in predicting the experimental behavior of the systems. Simulation results are able to account for the liquid-liquid phase equilibria of these binary mixtures, in good agreement with the experimental data taken from the literature. Unfortunately, experimental values for interfacial tensions are substantially overestimated by predictions from computer simulations in all cases. To our knowledge, this is the first time that the liquid-liquid phase equilibrium and interfacial properties of methyl ester + water mixtures have been predicted from computer simulations.

Enfermedad celíaca: un reto diagnóstico en Colombia / Celiac disease: a diagnostic challenge in Colombia

Introducción: la enfermedad celíaca (EC) es una patología sistémica inmunomediada por el gluten en la dieta en personas genéticamente susceptibles con un amplio rango de manifestaciones clínicas, respuesta serológica específica y un daño variable de la mucosa intestinal. Objetivo: revisar la fisiopatología, manifestaciones clínicas, diagnóstico, tratamiento, seguimiento y pronóstico de la EC, resaltando la importancia de reconocerla y proponer un algoritmo diagnóstico para la población colombiana. Materiales y métodos: revisión crítica de la literatura científica en las bases de datos Medline y buscadores específicos PUBMED, SCIENCE DIRECT, SCIELO, filtrando resultados a revisiones sistemáticas, metaanálisis, ensayos controlados aleatorios y guías de práctica clínica, con un total de 1209 artículos, de los cuales se priorizaron 53. Resultados y discusión: la prevalencia de la EC viene en aumento en países en vía de desarrollo. El diagnóstico tiene tres pilares fundamentales: la identificación de casos de alto riesgo o sospecha por manifestaciones clínicas, un perfil serológico de anticuerpos específicos y hallazgos histológicos característicos. El tratamiento se basa en una dieta sin gluten, en la detección temprana de complicaciones y el manejo de las alteraciones nutricionales. Conclusión: en Colombia no existen protocolos de diagnóstico y tratamiento de la EC, como tampoco una legislación clara con respecto al etiquetado de productos libres de gluten. Hay que establecer estrategias para impactar el curso natural de la enfermedad, las morbilidades asociadas y la calidad de vida de los pacientes.

Introduction: celiac disease (CD) is a systemic diet-gluten-immune-mediated enteropathy occurring in genetically susceptible individuals featuring a broad range of clinical manifestations, a specific serological response and variable intestinal mucosal damage. Objective: to review CD pathophysiology, clinical manifestations, diagnosis, treatment, follow-up and prognosis, highlighting the importance of awareness about this disorder and development of a diagnostic algorithm for Colombian population. Materials and methods: scientific literature critical review in the Medline databases and PUBMED, SCIENCE DIRECT, SCIELO specific search engines, using filters to retrieve systematic reviews, metanalyses, randomized controlled trials and clinical practice guidelines, finding 1209 articles, prioritizing 53. Results and discussion: the prevalence of CD is increasing in developing countries. Diagnosis is based on 3 fundamental pillars: identification of higher-risk populations or suspicion based on clinical manifestations, serological profile of specific antibodies and characteristic histological findings. Treatment is based on a gluten-free diet, early detection of complications and nutritional alterations management. Conclusion: there are no CD diagnosis and treatment protocols, nor clear regulations on labelling gluten-free products, in Colombia. Establishing strategies to impact the natural course of CD, associated morbidities and quality of life, is required

Neonatal Development in Prenatally Zika Virus-Exposed Infant Macaques with Dengue Immunity.

Infants exposed to Zika virus (ZIKV) prenatally may develop birth defects, developmental deficits, or remain asymptomatic. It is unclear why some infants are more affected than others, although enhancement of maternal ZIKV infection via immunity to an antigenically similar virus, dengue virus (DENV), may play a role. We hypothesized that DENV immunity may worsen prenatal ZIKV infection and developmental deficits in offspring. We utilized a translational macaque model to examine how maternal DENV immunity influences ZIKV-exposed infant macaque neurodevelopment in the first month of life. We inoculated eight macaques with prior DENV infection with ZIKV, five macaques with ZIKV, and four macaques with saline. DENV/ZIKV-exposed infants had significantly worse visual orientation skills than ZIKV-exposed infants whose mothers were DENV-naive, with no differences in motor, sensory or state control development. ZIKV infection characteristics and pregnancy outcomes did not individually differ between dams with and without DENV immunity, but when multiple factors were combined in a multivariate model, maternal DENV immunity combined with ZIKV infection characteristics and pregnancy parameters predicted select developmental outcomes. We demonstrate that maternal DENV immunity exacerbates visual orientation and tracking deficits in ZIKV-exposed infant macaques, suggesting that human studies should evaluate how maternal DENV immunity impacts long-term neurodevelopment.

Previous exposure to dengue virus is associated with increased Zika virus burden at the maternal-fetal interface in rhesus macaques.

Concerns have arisen that pre-existing immunity to dengue virus (DENV) could enhance Zika virus (ZIKV) disease, due to the homology between ZIKV and DENV and the observation of antibody-dependent enhancement (ADE) among DENV serotypes. To date, no study has examined the impact of pre-existing DENV immunity on ZIKV pathogenesis during pregnancy in a translational non-human primate model. Here we show that macaques with a prior DENV-2 exposure had a higher burden of ZIKV vRNA in maternal-fetal interface tissues as compared to DENV-naive macaques. However, pre-existing DENV immunity had no detectable impact on ZIKV replication kinetics in maternal plasma, and all pregnancies progressed to term without adverse outcomes or gross fetal abnormalities detectable at delivery. Understanding the risks of ADE to pregnant women worldwide is critical as vaccines against DENV and ZIKV are developed and licensed and as DENV and ZIKV continue to circulate.

African-Lineage Zika Virus Replication Dynamics and Maternal-Fetal Interface Infection in Pregnant Rhesus Macaques.

Following the Zika virus (ZIKV) outbreak in the Americas, ZIKV was causally associated with microcephaly and a range of neurological and developmental symptoms, termed congenital Zika syndrome (CZS). The viruses responsible for this outbreak belonged to the Asian lineage of ZIKV. However, in vitro and in vivo studies assessing the pathogenesis of African-lineage ZIKV demonstrated that African-lineage isolates often replicated to high titers and caused more-severe pathology than Asian-lineage isolates. To date, the pathogenesis of African-lineage ZIKV in a translational model, particularly during pregnancy, has not been rigorously characterized. Here, we infected four pregnant rhesus macaques with a low-passage-number strain of African-lineage ZIKV and compared its pathogenesis to those for a cohort of four pregnant rhesus macaques infected with an Asian-lineage isolate and a cohort of mock-inoculated controls. The viral replication kinetics for the two experimental groups were not significantly different, and both groups developed robust neutralizing antibody titers above levels considered to be protective. There was no evidence of significant fetal head growth restriction or gross fetal harm at delivery (1 to 1.5 weeks prior to full term) in either group. However, a significantly higher burden of ZIKV viral RNA (vRNA) was found in the maternal-fetal interface tissues of the macaques exposed to an African-lineage isolate. Our findings suggest that ZIKV of any genetic lineage poses a threat to pregnant individuals and their infants. IMPORTANCE ZIKV was first identified in 1947 in Africa, but most of our knowledge of ZIKV is based on studies of the distinct Asian genetic lineage, which caused the outbreak in the Americas in 2015 to 2016. In its most recent update, the WHO stated that improved understanding of African-lineage ZIKV pathogenesis during pregnancy must be a priority. The recent detection of African-lineage isolates in Brazil underscores the need to understand the impact of these viruses. Here, we provide the first comprehensive assessment of African-lineage ZIKV infection during pregnancy in a translational nonhuman primate model. We show that African-lineage isolates replicate with kinetics similar to those of Asian-lineage isolates and can infect the placenta. However, there was no evidence of more-severe outcomes with African-lineage isolates. Our results highlight both the threat that African-lineage ZIKV poses to pregnant individuals and their infants and the need for epidemiological and translational in vivo studies with African-lineage ZIKV.