Differences between Myeloschisis and Myelomeningocele in patients undergoing prenatal repair of Open Spina Bifida.

INTRODUCTION: Open spina bifida (OSB) manifests as myelomeningocele (MMC) or myeloschisis (MS). Both lesions theoretically leak cerebrospinal fluid (CSF) and produce different degrees of Chiari II malformation (CHMII). However, it is not entirely clear whether these forms of OSB have different clinical manifestations. This study aimed to evaluate the clinical and/or radiological differences between myeloschisis and myelomeningocele in patients who underwent prenatal OSB repair. METHODS: A total of 71 prenatal repairs were performed with the open technique at the Public Hospital of Rancagua, Chile, between 2012 and 2022. We performed follow-up MRI imaging of fetuses that qualified for prenatal OSB repair surgery. We examined the correlations between various anthropomorphic measurements and clinical and imaging variables, such as the type of lesion and dimensions such as ventricle atrium diameter, degree of severity of CHMII, need for CSF shunt at 12 months, and walking at 30 months. RESULTS: This study included 71 fetuses with OSB for which 38 MRI examinations were analyzed; 61% (43/71) of lesions were MMC and 39% (28/71) were MS. Grade 3 (severe) CHMII were found in 80% (12/15) of MS and 43% (10/23) of MMC (p<0.05). Fetuses with an atrial diameter less than 13.48 mm had a lower probability of requiring a CSF shunt at 12 months (p<0.05). MMC was associated with a higher frequency of clubfoot at birth (p<0.05), whereas MS was significantly associated with more severe CHMII (p<0.05). Although the correlations were not significant, we observed clear trends that more children with MS required shunts at 12 months and could walk at 30 months compared to children with MMC. CONCLUSIONS: MS and MMC are distinct subtypes of OSB. Further studies of larger cohorts that include biomolecular and histological analysis are required to better understand differences between these lesions. This study may enable healthcare providers to better advise parents and prepare healthcare teams earlier for the management of patients undergoing prenatal repair of OSB.

Registro multicéntrico Impella CP para shock cardiogénico o angioplastía de alto riesgo protegida en Chile

Antecedentes: El Shock Cardiogénico (SC) y las Angioplastías de Alto Riesgo (AAR) están asociadas con altas tasas de mortalidad. El uso del dispositivo Impella CP podría reducir el riesgo de muerte en estos escenarios. En Chile no existen reportes evaluando el uso del dispositivo Impella CP. Objetivo: Analizar los desenlaces clínicos en pacientes que fueron sometidos al uso del dispositivo Impella CP por SC o por AAR. Métodos: Se realizó un estudio retrospectivo en 17 pacientes, los cuales representan el total de implantes realizados en el país, entre octubre 2021 y agosto 2023. Se describió las características, demográficas, procedimentales y después del implante. Se estimó la mortalidad general y se identificaron factores asociados. Resultados: La edad de los pacientes fue 69± 3,7 años y 88,2% fueron hombres. El 64,7% recibió el dispositivo por SC y 35,3% por AAR. Dentro de las comorbilidades estudiadas, la hipertensión arterial fue la más frecuente, 94,1%. Un 58,8% de los pacientes fueron revascularizados a través de la arteria radial. El 29,4% recibió el dispositivo previo a la angioplastía y 70,6% lo recibió después. El 47,1% de las angioplastías fue guiada por imágenes. En 11,8% de ellos se realizó litotricia intracoronaria y 5,9% por ablación intracoronaria. Los pacientes estuvieron 13 ±3,4 días con el soporte. La mortalidad global fue de 41,2%. Conclusiones: El uso del dispositivo Impella presentó pocas complicaciones vasculares. La mortalidad asociada con su colocación en Chile fue relativamente similar con la reportada en la literatura.

Background: Cardiogenic shock and high-risk Angioplasty are associated with a high mortality rate. Using the Impella CP device could reduce the risk of death in these scenarios. In Chile, there are no studies evaluating the use of the Impella CP device. Objective: To analyse the clinical outcomes in patients who have undergone placement of the Impella CP device for cardiogenic shock and high-risk angioplasties. Methods: A retrospective study was carried out on 17 patients, which represent the total number of implants performed in the country, between October 2021 and August 2023. The demographic, procedural and post-implant characteristics were described. Overall mortality and associated factors were identified. Results: The age was 69± 3.7 years, where 88.2% were men. 64.7% of patients received the device by SC and 35.3% by AAR. Among the comorbidities studied, arterial hypertension was the most frequent with 94.1%. 58.8% of patients were revascularized through the radial artery. 29.4% of patients received the device before angioplasty and 70.6% received it afterwards. 47.1% of angioplasties were image-guided, 11.8% had intracoronary lithotripsy, and 5.9% had intracoronary ablation. The patients spent 13 ±3.4 days with the support. Overall mortality was 41.2%. Conclusion: use of the Impella device was associated with few vascular complications. Mortality associated with use of the Impella device in Chile was similar to that previously reported in other studies.

Analysis of microbiota-host communication mediated by butyrate in Atlantic salmon.

Butyrate is a microbiota-produced metabolite, sensed by host short-chain fatty acid receptors FFAR2 (Gpr43), FFAR3 (Gpr41), HCAR2 (Gpr109A), and Histone deacetylase (HDAC) that promotes microbiota-host crosstalk. Butyrate influences energy uptake, developmental and immune response in mammals. This microbial metabolite is produced by around 79 anaerobic genera present in the mammalian gut, yet little is known about the role of butyrate in the host-microbiota interaction in salmonid fish. To further our knowledge of this interaction, we analyzed the intestinal microbiota and genome of Atlantic salmon (Salmo salar), searching for butyrate-producing genera and host butyrate receptors. We identified Firmicutes, Proteobacteria, and Actinobacteria as the main butyrate-producing bacteria in the salmon gut microbiota. In the Atlantic salmon genome, we identified an expansion of genes orthologous to FFAR2 and HCAR2 receptors, and class I and IIa HDACs that are sensitive to butyrate. In addition, we determined the expression levels of orthologous of HCAR2 in the gut, spleen, and head-kidney, and FFAR2 in RTgutGC cells. The effect of butyrate on the Atlantic salmon immune response was evaluated by analyzing the pro and anti-inflammatory cytokines response in vitro in SHK-1 cells by RT-qPCR. Butyrate decreased the expression of the pro-inflammatory cytokine IL-1ß and increased anti-inflammatory IL-10 and TGF-ß cytokines. Butyrate also reduced the expression of interferon-alpha, Mx, and PKR, and decreased the viral load at a higher concentration (4 mM) in cells treated with this molecule before the infection with Infectious Pancreatic Necrosis Virus (IPNV) by mechanisms independent of FFAR2, FFAR3 and HCAR2 expression that probably inhibit HDAC. Moreover, butyrate modified phosphorylation of cytoplasmic proteins in RTgutGC cells. Our data allow us to infer that Atlantic salmon have the ability to sense butyrate produced by their gut microbiota via different specific targets, through which butyrate modulates the immune response of pro and anti-inflammatory cytokines and the antiviral response.

Evaluation and comparison of the sensitivity of three commercial RT-qPCR kits used for the detection of SARS-CoV-2 in Santiago, Chile.

Introduction: The COVID-19 pandemic is still in force, causing global public health challenges and threats. Although vaccination and herd immunity have proven to be the most efficient way to control the pandemic, massive and early testing of patients using the RT-qPCR technique is crucial for constant genomic surveillance. The appearance of variants of SARS-CoV-2 with new mutations can reduce the efficiency of diagnostic detection. In this sense, several commercial RT-qPCR kits have been the target of extensive analysis because low assay performance could lead to false-negative diagnoses. Methods: In this study, we evaluated the performance of three commercial RT-qPCR kits; Thermo Fisher (TaqMan 2019-nCoV Assay Kit v1), BGI and Roche (LightCycler® Multiplex RNA Virus Master) used for the diagnosis of COVID-19 throughout the pandemic in Santiago de Chile. Results: Under our best assay conditions, we found significant differences in Cq amplification values for control and viral probes, against the same nasopharyngeal swab samples (NPSs). In addition, in some cases, the sensitivity of the RT-qPCR kits decreased against viral variants. Conclusion: Our study suggests evaluating the RT-qPCR kits used to detect SARS-CoV-2 because variants such as Omicron, which has several mutations, can compromise their detection and underestimate viral circulation.

Inactivated Vaccine-Induced SARS-CoV-2 Variant-Specific Immunity in Children.

Multiple vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been evaluated in clinical trials. However, trials addressing the immune response in the pediatric population are scarce. The inactivated vaccine CoronaVac has been shown to be safe and immunogenic in a phase 1/2 clinical trial in a pediatric cohort in China. Here, we report interim safety and immunogenicity results of a phase 3 clinical trial for CoronaVac in healthy children and adolescents in Chile. Participants 3 to 17 years old received two doses of CoronaVac in a 4-week interval until 31 December 2021. Local and systemic adverse reactions were registered for volunteers who received one or two doses of CoronaVac. Whole-blood samples were collected from a subgroup of 148 participants for humoral and cellular immunity analyses. The main adverse reaction reported after the first and second doses was pain at the injection site. Four weeks after the second dose, an increase in neutralizing antibody titer was observed in subjects relative to their baseline visit. Similar results were found for activation of specific CD4+ T cells. Neutralizing antibodies were identified against the Delta and Omicron variants. However, these titers were lower than those for the D614G strain. Importantly, comparable CD4+ T cell responses were detected against these variants of concern. Therefore, CoronaVac is safe and immunogenic in subjects 3 to 17 years old, inducing neutralizing antibody secretion and activating CD4+ T cells against SARS-CoV-2 and its variants. (This study has been registered at ClinicalTrials.gov under no. NCT04992260.) IMPORTANCE This work evaluated the immune response induced by two doses of CoronaVac separated by 4 weeks in healthy children and adolescents in Chile. To date, few studies have described the effects of CoronaVac in the pediatric population. Therefore, it is essential to generate knowledge regarding the protection of vaccines in this population. Along these lines, we reported the anti-S humoral response and cellular immune response to several SARS-CoV-2 proteins that have been published and recently studied. Here, we show that a vaccination schedule consisting of two doses separated by 4 weeks induces the secretion of neutralizing antibodies against SARS-CoV-2. Furthermore, CoronaVac induces the activation of CD4+ T cells upon stimulation with peptides from the proteome of SARS-CoV-2. These results indicate that, even though the neutralizing antibody response induced by vaccination decreases against the Delta and Omicron variants, the cellular response against these variants is comparable to the response against the ancestral strain D614G, even being significantly higher against Omicron.

Analysis by real-time PCR of five transport and conservation mediums of nasopharyngeal swab samples to COVID-19 diagnosis in Santiago of Chile.

Due to the COVID-19 pandemic, many transport kits have been manufactured to preserve and transport nasopharyngeal swab samples (NPSs) from patients. However, there is no information on the performance of the different virus transport media (VTM) used in COVID-19 diagnosis in the population of Santiago de Chile. We compared the RT-qPCR amplification profile of five different viral transport kit mediums, including DNA/RNA Shield™, NAT, VTM-N, Ezmedlab™, and phosphate-buffered saline (PBS), for NPSs from Central Metropolitan Health Service, Santiago, Chile. The DNA/RNA Shield™ medium showed a better performance in terms of Cq and RFU values for the internal reference RNase P and viral ORF1ab probes. By contrast, the PBS transport medium registered higher Cq values for the viral and reference gene, compared to the other VTM. DNA/RNA Shield™ shows higher relative fluorescence units (RFUs) and lower Cq values for the reference gene. Collectively, our results suggest that the PBS medium could compromise the sample diagnosis because of its lower RT-qPCR performance. The NAT, Ezmedlab and VTM-N, and DNA/RNA Shield™ media show acceptable RT-qPCR parameters and, consequently, seem suitable for use in COVID-19 diagnosis.

Oral Administration of Lactococcus lactis Producing Interferon Type II, Enhances the Immune Response Against Bacterial Pathogens in Rainbow Trout.

Lactic acid bacteria are a powerful vehicle for releasing of cytokines and immunostimulant peptides at the gastrointestinal level after oral administration. However, its therapeutic application against pathogens that affect rainbow trout and Atlantic salmon has been little explored. Type II interferon in Atlantic salmon activates the antiviral response, protecting against viral infection, but its role against bacterial infection has not been tested in vivo. In this work, through the design of a recombinant lactic acid bacterium capable of producing Interferon gamma from Atlantic salmon, we explore its role against bacterial infection and the ability to stimulate systemic immune response after oral administration of the recombinant probiotic. Recombinant interferon was active in vitro, mainly stimulating IL-6 expression in SHK-1 cells. In vivo, oral administration of the recombinant probiotic produced an increase in IL-6, IFNγ and IL-12 in the spleen and kidney, in addition to stimulating the activity of lysozyme in serum. The challenge trials indicated that the administration of the IFNγ-producing probiotic doubled the survival in fish infected with F. psychrophilum. In conclusion, our results showed that the oral administration of lactic acid bacteria producing IFNγ managed to stimulate the immune response at a systemic level, conferring protection against pathogens, showing a biotechnological potential for its application in aquaculture.

Smartphone screen testing, a novel pre-diagnostic method to identify SARS-CoV-2 infectious individuals.

The COVID-19 pandemic will likely take years to control globally, and constant epidemic surveillance will be required to limit the spread of SARS-CoV-2, especially considering the emergence of new variants that could hamper the effect of vaccination efforts. We developed a simple and robust - Phone Screen Testing (PoST) - method to detect SARS-CoV-2-positive individuals by RT-PCR testing of smartphone screen swab samples. We show that 81.3-100% of individuals with high-viral-load SARS-CoV-2 nasopharyngeal-positive samples also test positive for PoST, suggesting this method is effective in identifying COVID-19 contagious individuals. Furthermore, we successfully identified polymorphisms associated with SARS-CoV-2 Alpha, Beta, and Gamma variants, in SARS-CoV-2-positive PoST samples. Overall, we report that PoST is a new non-invasive, cost-effective, and easy-to-implement smartphone-based smart alternative for SARS-CoV-2 testing, which could help to contain COVID-19 outbreaks and identification of variants of concern in the years to come.

Dolor en Aves y Peces / Pain in Birds and Fish

Se ha demostrado que aves y peces presentan estructuras anatómicas similares a las que transducen el dolor en humanos y, además, muestran respuestas negativas frente a estímulos nocivos, junto a cambios conductuales. De acuerdo con esto, existe una responsabilidad moral frente al uso de estos animales en investigación para evitar y/o minimizar el dolor.

Birds and fish have been shown to present anatomical structures similar to those that transduce pain in humans, and also show negative responses to harmful stimuli, along with behavioural changes. There is a moral responsibility regarding the use of these animals in research to avoid and/or minimize pain. In this review we compare the pain-related morphology of birds and fish, using pain in humans as a starting point.

Development of an Isavirus minigenome system to study the function of the pocket RNA-binding domain of the viral nucleoprotein (NP) in salmon cells.

The Isavirus is an orthomyxovirus with a genome composed of eight segments of negative single-strand RNA (-ssRNA). It has been proposed that the eight genomic segments of the Isavirus are organized as a ribonucleoprotein (RNP) complex called a minigenome, which contains all the viral RNA segments, a viral heterotrimeric polymerase and multiple copies of the viral nucleoprotein (NP). Here, we develop an Isavirus minigenome system and show the importance of the formation of active RNPs and the role of viral NP R189, R194, R302 and K325 residues in the NP RNA-binding domain in the context of RNPs. The results indicate it is possible to generate a minigenome in salmon cells, a composite ISAV RNPs with EGFP-based chimeric vRNA with heterotrimeric polymerase (PB1, PB2, PA) and NP protein using CMV-based auxiliary plasmids. It was also shown that NP R189, R194, R302 and K325 residues are important to generate viral mRNA from the constituted RNPs and a detectable reporter protein. This work is the first salmon cell-based minigenome assay for the Isavirus, which was evaluated by a bioinformatic and functional study of the NP protein in viral RNPs, which showed that correct NP-vRNA interaction is key to the functioning of RNPs.

Effect of intrauterine injection of human chorionic gonadotropin before embryo transfer on clinical pregnancy rates from in vitro fertilisation cycles: a prospective study.

BACKGROUND: The implantation process after embryo transfer depends on the embryo quality and endometrial receptivity. It is estimated that fifty to seventy-five per cent of pregnancies are lost due to a failure of implantation. There is evidence that there is an early secretion of human chorionic gonadotrophin before embryo implantation, and this secretion has been linked to an important function in angiogenesis and the inflammatory response that promotes the implantation process. Our objective was to determine the effects of intrauterine injection of human chorionic gonadotropin (hCG) before the embryo transfer in an in vitro fertilisation cycle. METHODS: A prospective randomised study was conducted in Reproductive Medicine Centre PROCREA in Mexico City. Infertile patients who had a medical indication for in vitro fertilisation were studied. Two groups were included (n 210); the intervention group received an intrauterine injection of 500 IU of hCG before the embryo transfer (n 101). The control group (n 109) did not receive hCG. Comparisons were performed using a chi-square test. RESULTS: The clinical pregnancy rate (CPR) was our principal outcome. The implantation rate was a secondary outcome. The implantation rate was significantly higher in the hCG group compared to the control group (52.4% vs 35.7%, p 0.014). The clinical pregnancy rate was also significantly higher (50.4 vs 33.0%, p 0.010). No adverse effects were observed. CONCLUSIONS: The intrauterine injection of hCG before embryo transfer showed a significant increase in the clinical pregnancy rate. More clinical trials are needed to reproduce these results on this promising intervention. The live birth rate must be included in subsequent studies.