Immunized mice naturally process in silico-derived peptides from the nucleocapsid of SARS-CoV-2.

BACKGROUND: The nucleocapsid (N) protein of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is an excellent immunogen that promotes the production of high-titer antibodies. N protein-derived peptides identified using a bioinformatics approach can potentially be used to develop a new generation of vaccines or diagnostic methods for detecting SARS-CoV-2 and its variants. However, further studies must demonstrate their capacity to be naturally processed by the immune system. OBJECTIVE: We aimed to examine the in vivo processing and recognition of in silico-identified peptides using the serum of immunized animals with the complete protein. METHODS: Recombinant N (Nrec) protein was subcutaneously administered to six Balb/c mice. Enzyme-linked immunosorbent assay (ELISA), western blotting, dot blotting, and immunoprecipitation were performed to evaluate the recognition of the complete protein and in silico-derived peptides. RESULTS: The serum of immunized mice recognized ~ 62.5 ng/µL of Nrec with high specificity to linear and conformational epitopes. Dot blot analysis showed that peptides Npep2 and Npep3 were the most reactive. CONCLUSION: Our data confirm the high immunogenicity of the SARS-CoV-2 N protein and provide evidence on the antigenicity of two peptides located in the N-arm/RNA-binding domain (Npep2) and oligomerization domain/C-tail (Npep3), considered the biologically active site of the N protein.

Technical Implications of the Chicken Embryo Chorioallantoic Membrane Assay to Elucidate Neuroblastoma Biology.

The chorioallantoic membrane (CAM) can be used as a valuable research tool to examine tumors. The CAM can be used to investigate processes such as migration, invasion, and angiogenesis and to assess novel antitumor drugs. The CAM can be used to establish tumors in a straightforward, rapid, and cost-effective manner via xenotransplantation of cells or tumor tissues with reproducible results; furthermore, the use of the CAM adheres to the three "R" principle, i.e., replace, reduce, and refine. To achieve successful tumor establishment and survival, several technical aspects should be taken into consideration. The complexity and heterogeneity of diseases including neuroblastoma and cancers in general and their impact on human health highlight the importance of preclinical models that help us describe tumor-specific biological processes. These models will not only help in understanding tumor biology, but also allow clinicians to explore therapeutic alternatives that will improve current treatment strategies. In this review, we summarize the technical characteristics as well as the main findings regarding the use of this model to study neuroblastoma for angiogenesis, metastasis, drug sensitivity, and drug resistance.

Behavior of immunoglobulin G antibodies for SARS-COV-2 in Mexican pediatric patients with comorbidities: a prospective comparative cohort study.

Background: More than two years after the pandemic of COVID-19 caused by the severe acute respiratory syndrome coronavirus 2 (SARS-COV-2) there is a great lack of information. The presence of immunoglobulin G (IgG) have been related with disease severity. Patients with comorbidities could develop more severe infection; however, the evaluation of the humoral response in pediatric population are needed especially in patients with comorbidities. Our aim was to describe the behavior of IgG in pediatric patients and to know if there is a difference between patients with comorbidities. Methods: A prospective comparative cohort study was carried out in a single center from June 2020 to January 2021, with a follow-up of 6 months. The study included all the subjects with confirmatory test for SARS-CoV-2 from 1 month to 17 years 11 months, the follow-up of the disease's evolution and measurement of IgG antibodies was collected. We obtained the clinical data, and comorbidities like arterial hypertension, diabetes, obesity, and cancer, the initial symptoms were recorded as well as the evolution regarding the severity of COVID-19 and the need for hospitalization, intensive care unit or mechanical ventilation. The follow up was carried out through medical consultation with an appointment every month that included direct interrogation, examination, and peripheral blood collection for the IgG quantification. The antibodies detection was done through peripheral blood and chemiluminescence microparticle immunoassay. Results: A total of 237 patients with positive polymerase chain reaction (PCR) for SARS-COV-2 were included, of which 147 presented IgG antibodies (62%), 112 (76%) without comorbidity and 35 (24%) with comorbidities, by the sixth month only 2.7% continue with positive antibody measurements. Patients with comorbidities reach higher IgG levels than patients without comorbidities the basal titters were: 5.17 for patients without comorbidities vs. 6.96 for the group with comorbidities (P<0.001). Conclusions: We found an association between the presence of comorbidities and high levels of IgG units in pediatric patients with COVID-19. Additionally, patients with more severe course of the disease have higher levels of IgG and by the third month less than 35% have immunity.

Normal development of the heart: a review of new findings / Desarrollo normal del corazón: revisión de nuevos hallazgos

Abstract Development and formation of the heart, the central organ of the circulatory system in vertebrates, starts early during embryonic development (second week), reaching maturity during the first few postnatal months. Cardiogenesis is a highly complex process that requires the active and orderly participation of different cardiac and non-cardiac cell populations. Thus, this process is sensitive to errors that may trigger a variety of heart-development defects, called congenital heart defects, which have a worldwide incidence of 8-10/1000 live births. A good understanding of normal cardiogenesis is required for better diagnosis and treatment of congenital heart diseases. This article reviews normal cardiogenesis by comparing information from classic studies with more recent findings. Information from descriptive anatomical studies of histological sections and selective in vivo marking of chicken embryos were emphasized. In addition, the discovery of heart fields has fueled the investigation of cardiogenic events that were believed to be understood and has contributed to proposals for new models of heart development.

Resumen El corazón, órgano central del aparato circulatorio de los vertebrados, comienza a formarse muy temprano en el desarrollo embrionario (segunda semana de gestación) y alcanza su forma madura durante los primeros meses posteriores al nacimiento. La cardiogénesis se caracteriza por ser un proceso altamente complejo, dependiente de la participación activa y ordenada de diferentes poblaciones celulares cardiacas y no cardiacas. Lo anterior hace que este proceso sea sensible a errores que pueden desencadenar una variedad de defectos del desarrollo cardiaco, llamados cardiopatías congénitas, con una incidencia mundial de 8 a 10/1000 nacidos vivos. Para mejorar el diagnóstico y el tratamiento de las cardiopatías congénitas es necesario comprender adecuadamente los eventos implicados en la cardiogénesis normal. En este artículo se revisa el desarrollo cardiaco normal, contrastando la información de los estudios clásicos con la de hallazgos recientes. Se hace hincapié en la información obtenida de los estudios de anatomía descriptiva de cortes histológicos y marcaje selectivo in vivo en embriones de pollo. Adicionalmente, el descubrimiento de los campos cardiogénicos ha estimulado la investigación de eventos cardiogénicos que se creían comprendidos, contribuyendo con propuestas de nuevos modelos del desarrollo del corazón.

HP0953 - hypothetical virulence factor overexpresion and localization during Helicobacter pylori infection of gastric epithelium.

BACKGROUND: The high prevalence and persistence of Helicobacter pylori (H. pylori) infection, as well as the diversity of pathologies related to it, suggest that the virulence factors used by this microorganism are varied. Moreover, as its proteome contains 340 hypothetical proteins, it is important to investigate them to completely understand the mechanisms of its virulence and survival. We have previously reported that the hypothetical protein HP0953 is overexpressed during the first hours of adhesion to inert surfaces, under stress conditions, suggesting its role in the environmental survival of this bacterium and perhaps as a virulence factor. AIM: To investigate the expression and localization of HP0953 during adhesion to an inert surface and against gastric (AGS) cells. METHODS: Expression analysis was performed for HP0953 during H. pylori adhesion. HP0953 expression at 0, 3, 12, 24, and 48 h was evaluated and compared using the Kruskal-Wallis equality-of-populations rank test. Recombinant protein was produced and used to obtain polyclonal antibodies for immunolocalization. Immunogold technique was performed on bacterial sections during adherence to inert surfaces and AGS cells, which was analyzed by transmission electron microscopy. HP0953 protein sequence was analyzed to predict the presence of a signal peptide and transmembrane helices, both provided by the ExPASy platform, and using the GLYCOPP platform for glycosylation sites. Different programs, via, I-TASSER, RaptorX, and HHalign-Kbest, were used to perform three-dimensional modeling. RESULTS: HP0953 exhibited its maximum expression at 12 h of infection in gastric epithelium cells. Immunogold technique revealed HP0953 localization in the cytoplasm and accumulation in some peripheral areas of the bacterial body, with greater expression when it is close to AGS cells. Bioinformatics analysis revealed the presence of a signal peptide that interacts with the transmembrane region and then allows the release of the protein to the external environment. The programs also showed a similarity with the Tip-alpha protein of H. pylori. Tip-alpha is an exotoxin that penetrates cells and induces tumor necrosis factor alpha production, and HP0953 could have a similar function as posttranslational modification sites were found; modifications in turn require enzymes located in eukaryotic cells. Thus, to be functional, HP0953 may necessarily need to be translocated inside the cell where it can trigger different mechanisms producing cellular damage. CONCLUSION: The location of HP0953 around infected cells, the probable posttranslational modifications, and its similarity to an exotoxin suggest that this protein is a virulence factor.

Clinical features and severe acute respiratory syndrome-coronavirus-2 structural protein-based serology of Mexican children and adolescents with coronavirus disease 2019.

Severe acute respiratory syndrome (SARS)-coronavirus (CoV)-2 infection in children and adolescents primarily causes mild or asymptomatic coronavirus disease 2019 (COVID-19), and severe illness is mainly associated with comorbidities. However, the worldwide prevalence of COVID-19 in this population is only 1%-2%. In Mexico, the prevalence of COVID-19 in children has increased to 10%. As serology-based studies are scarce, we analyzed the clinical features and serological response (SARS-CoV-2 structural proteins) of children and adolescents who visited the Hospital Infantil de México Federico Gómez (October 2020-March 2021). The majority were 9-year-old children without comorbidities who were treated as outpatients and had mild-to-moderate illness. Children aged 6-10 years and adolescents aged 11-15 years had the maximum number of symptoms, including those with obesity. Nevertheless, children with comorbidities such as immunosuppression, leukemia, and obesity exhibited the lowest antibody response, whereas those aged 1-5 years with heart disease had the highest levels of antibodies. The SARS-CoV-2 spike receptor-binding domain-localized peptides and M and E proteins had the best antibody response. In conclusion, Mexican children and adolescents with COVID-19 represent a heterogeneous population, and comorbidities play an important role in the antibody response against SARS-CoV-2 infection.

Unusual Inflammatory Tinea Infections: Majocchi's Granuloma and Deep/Systemic Dermatophytosis.

PURPOSE OF REVIEW: Inflammatory tinea is an uncommon group of dermatophyte entities that predominantly cause fungal infection of the skin and hair. This review intends to present all of the available evidence regarding its epidemiology, etiopathogenesis, clinical features, and diagnostic methods as well as treatments recommended for various inflammatory tinea infections. This article provides a review of Majocchi's granuloma and dermatophytic or Hadida's disease. RECENT FINDINGS: The new phylogenetic classification of dermatophytes includes nine genera, and those that affect humans are Trichophyton, Microsporum, Epidermophyton, and Nannizzia. Furthermore, molecular advancements have revealed impaired antifungal immune responses caused by inflammatory tinea, which are detailed in this article. SUMMARY: The common denominator in these pathologies is the presence of impaired immune responses and, consequently, an impaired inflammatory response by the host. It is necessary to be familiar with these immunological characteristics in order to use the appropriate diagnostic methods and to provide adequate treatment.

Psychosocial Factors Predicting Resilience in Family Caregivers of Children with Cancer: A Cross-Sectional Study.

Chronic diseases in childhood can affect the physical and mental health of patients and their families. The objective of this study was to identify the sociodemographic and psychosocial factors that predict resilience in family caregivers of children with cancer and to define whether there are differences in the levels of resilience derived from these sociodemographic variables. Three hundred and thirty family caregivers of children with cancer, with an average age of 32.6 years were interviewed. The caregivers responded to a battery of tests that included a questionnaire of sociodemographic variables, the Measuring Scale of Resilience, the Beck Depression Inventory, the Inventory of Quality of Life, the Beck Anxiety Inventory, an interview of caregiver burden and the World Health Organization Well-Being Index. The main findings indicate that family caregivers of children with cancer reported high levels of resilience, which were associated positively with quality of life, psychological well-being and years of study and associated negatively with depression, anxiety and caregiver burden. The variables that predicted resilience in families of children with cancer were quality of life, psychological well-being, depression and number of children. Family caregivers who were married and Catholic showed higher resilience scores. We conclude that being a caregiver in a family with children with cancer is associated with symptoms of anxiety and with depressive episodes. These issues can be overcome through family strength, well-being, quality of life and positive adaptation processes and mobilization of family resources.

Antitumor Effects of Natural Compounds Derived from Allium sativum on Neuroblastoma: An Overview.

Garlic (Allium sativum) has been used in alternative medicine to treat several diseases, such as cardiovascular and neurodegenerative diseases, cancer, and hepatic diseases. Several publications have highlighted other features of garlic, including its antibacterial, antioxidative, antihypertensive, and antithrombotic properties. The properties of garlic result from the combination of natural compounds that act synergistically and cause different effects. Some garlic-derived compounds have been studied for the treatment of several types of cancer; however, reports on the effects of garlic on neuroblastoma are scarce. Neuroblastoma is a prevalent childhood tumor for which the search for therapeutic alternatives to improve treatment without affecting the patients' quality of life continues. Garlic-derived compounds hold potential for the treatment of this type of cancer. A review of articles published to date on some garlic compounds and their effect on neuroblastoma was undertaken to comprehend the possible therapeutic role of these compounds. This review aimed to analyze the impact of some garlic compounds on cells derived from neuroblastoma.

Neuroprotective Effects of Quercetin in Pediatric Neurological Diseases.

Oxidative stress is a crucial event underlying several pediatric neurological diseases, such as the central nervous system (CNS) tumors, autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD). Neuroprotective therapy with natural compounds used as antioxidants has the potential to delay, ameliorate or prevent several pediatric neurological diseases. The present review provides an overview of the most recent research outcomes following quercetin treatment for CNS tumors, ASD and ADHD as well as describes the potential in vitro and in vivo ameliorative effect on oxidative stress of bioactive natural compounds, which seems like a promising future therapy for these diseases. The neuroprotective effects of quercetin against oxidative stress can also be applied in the management of several neurodegenerative disorders with effects such as anti-cancer, anti-inflammatory, anti-viral, anti-obesity and anti-microbial. Therefore, quercetin appears to be a suitable adjuvant for therapy against pediatric neurological diseases.

The Social Support Networks Scale (SSNS) for Family Caregivers of Children with Cancer: A Psychometric Evaluation.

Currently, information about the psychometric properties of the Social Support Networks Scale (SSNS) for family caregivers of children with cancer is not yet available; therefore, there is no empirical evidence of its validity and reliability to support its use in this population. The aim of this study is to determine a factorial model of the SSNS, estimate its internal consistency reliability, describe its distribution, and check its concurrent validity. A convenience sample of 633 family caregivers of children with cancer hospitalized in a National Institute of Health in Mexico City was collected. The SSNS, a sociodemographic variables questionnaire, and three instruments that evaluated family functioning, quality of life, and resilience were applied. The five-factor model had a poor data fit and lacked discriminant validity. The sample was divided. In a subsample of 316 participants, exploratory factor analysis suggested a four-factor model. When testing the four-factor model through confirmatory factor analysis, religious support was independent of family support, friend support, and lack of support. In the other subsample of 317 participants, the one-factor model for religious support had a good fit, and the correlated three-factor model, with the remaining factors, showed an acceptable fit. Reliability ranged from acceptable (Guttman's λ2 = 0.72) to good (λ2 = 0.88). Socio-family support and its three factors were correlated with family functioning, resilience, and quality of life. Religious support was correlated with four factors of resilience and quality of life. A scale of socio-family support with three factors and an independent scale for religious support are defined from the SSNS, and they showed internal consistency and construct validity.

Role of Epstein-Barr Virus in Glioblastoma.

Gliomas are the most common and most lethal primary malignant adult brain tumors, and glioblastomas are the most frequent. Several risk factors are involved in their pathogenesis; these include environmental factors as well as host factors. The etiology of most gliomas remains unknown. Epstein-Barr Virus (EBV), a member of the Herpesviridae family, was the first tumoral virus to be described, and several viruses in connection with cancer were discovered thereafter. During the complex interaction between host and EBV, several events take place. In the context of survival, EBV can drive its host cells with subsequent disruption of the cellular machinery, leading to tumorigenesis as the final outcome. Thus, the EBV infection has been associated with different tumors. In this review, we discuss EBV and cancer. We have analyzed previously published papers and have conducted a critical analysis on the role of the viral infection in glioblastoma. Several works have described the presence of the virus, but none have shown a conclusive association. Thus, there is need to continue analyzing the interaction between host and virus to determine whether the viral presence is incidental or has some association with glioblastoma.

Thymidine Kinase: A Biomarker for Recently Diagnosed Acute Leukemia in Pediatric Patients According to the Cell Line Involved.

BACKGROUND AND AIMS: Acute leukemia (AL) is a heterogeneous group of diseases characterized by a disorganized clone proliferation of hematopoietic cells. Thymidine kinase (TK) is a cell enzyme involved in DNA synthesis and is considered a cellular proliferation marker in some solid tumors. METHODS: A cross-sectional prospective and comparative study was performed in the Federico Gomez Children's Hospital in Mexico (HIMFG, in Spanish) in 125 samples of patients of the HIMFG with AL and 138 samples of children without leukemia. Serum TK levels were determined for both groups. RESULTS: Of the children with AL, 90 presented B-cell acute lymphoblastic leukemia (B-ALL); 13, T-cell acute lymphoblastic leukemia (T-ALL); and 22, acute myeloid leukemia (AML). A median (m) TK level of 23.7 IU (IQR 17-35.7) was observed in the group without AL and 91 IU (IQR 98-392) in the AL group. This difference was statistically significant (p <0.0001). When analyzing TK levels according to the type of leukemia, the m was as follows: 68 IU (IQR 35-118) for B-ALL, 470 IU (IQR 88-750) for AML, and 1678 IU (IQR 288-2108) for T- ALL. CONCLUSION: TK is an enzyme showing heterogeneous levels in B-ALL although it is significantly increased in 90% of patients with T-ALL and AML.

Cistatina C como prueba de rutinapara evaluar la función renal en pacientes pediátricos / Cystatin C as a routine test to evaluate kidney function in pediatric patients

Numerosos estudios han demostrado que los niveles plasmáticos de cistatina C tienen más exactitud que los de creatinina en la estimación de la tasa de filtración glomerular (eTFG). Sin embargo, no se utiliza como prueba rutinaria en el diagnóstico de patologías renales pediátricas. El objetivo de este estudio fue comparar la TFG para cistatina C en pacientes pediátricos mexicanos con y sin exposición a factores de riesgo para presentar Insuficiencia Renal Aguda (IRA) y corroborar las ventajas de emplear este marcador en el diagnóstico oportuno de patologías renales en relación con la creatinina. Se analizaron 106 muestras para estimar la TFG. Se cuantificó la concentración de creatinina y cistatina C, sustituyendo los valores en las fórmulas MDRD v-4 y Filler y Lepage, respectivamente. Se compararon las concentraciones tanto de creatinina como de cistatina entre los grupos de estudio por medio de U de Mann Whitney. Asimismo, se evaluó la correlación entre estos dos metabolitos divididos por presencia o no de factores de riesgo para presentar la enfermedad renal. Se observó una correlación entre las concentraciones de creatinina y cistatina C sérica, tanto en el grupo de pacientes sin factores de riesgo para IRA (r=0,936, p<0,001) como en los que sí presentaron factores de riesgo para IRA (r=0,952, p<0,001).El grupo con factores de riesgo mostró concentraciones mayores tanto de cistatina como de creatinina, así como de eTFG para ambos metabolitos. La cistatina C muestra una buena correlación con la creatinina. Por otro lado,la cistatina alterada identificó a un mayor número de pacientes con factores de riesgo para IRA, por lo cual se propone su uso como prueba de escrutinio en pacientes pediátricos...

Los segmentos cardíacos primitivos, su implicación en la cardiogénesis normal aplicada a la cardiología pediátrica / Involvement of the primitive cardiac segments in the normal cardiogenesis. Its importance in the pediatric cardiology

The ample development of diagnostic echocardiography in pediatric cardiology has demanded precise knowledge of the abnormal anatomy of hearts that present congenital cardiac diseases. As a result, the information on morphologic and molecular aspects of cardiac embryogenesis has become fundamental to understand the anomalous anatomy of the malformed hearts. Based on these facts, in this paper we reviewed normal cardiogenesis, integrating the new information obtained experimentally in the chick embryo and from classic descriptive knowledge in humans. The age at which each cardiac segment appears is specified. At the same time, the changes in shape, relationships and position of these cardiac segments are detailed. Some implications of this process in the production of congenital cardiac defects and the importance of some specific genes are also discussed. This information is useful in the diagnosis of congenital cardiac diseases, as well as in discussing their embryogenesis. It is also beneficial in studying the possible mechanisms and genes implicated in normal morphogenesis of cardiac chambers, septa and valves. All this knowledge is important to plan strategies to avoid the production of this type of congenital pathologies.