Oil-in-Water Pickering Emulsions Stabilized with Nanostructured Biopolymers: A Venue for Templating Bacterial Cellulose.

Pickering emulsions (PEs) differ from conventional emulsions in the use of solid colloidal particles as stabilizing agents instead of traditional amphiphilic molecules. Nanostructured biopolymers (NBs) emerge as a promising alternative for PE stabilization owing to their remarkable biocompatibility, abundant availability, and low cost. To explore this potential, a study is herein presented, in which cellulose nanocrystals (CNCs), both type I and type II allomorphs, and chitin nanocrystals (ChNCs) were used for stabilizing oil-in-water PEs prepared by the use of ultrasound. Sunflower oil was selected as the oil phase as it offers the advantages of being edible, renewable, and inexpensive. By utilizing ζ-potential, static light diffraction, and visual observations, we determined the optimal oil/water ratio for each type of NB to obtain stable emulsions after 14 days. The optimized PEs were used to form bacterial nanocellulose composites through emulsion templating. To our knowledge, this study represents a pioneering work in exploiting oil-in-water PEs for this approach. Additionally, it entails the first utilization of nonmercerized type II CNCs as stabilizers for PEs, while also establishing a direct comparison among the most relevant NBs. The resulting composites exhibited a unique morphology, composed of larger pores compared to standard bacterial nanocellulose aerogels. These findings highlight the notable potential of NBs as stabilizers for PEs and their ability to generate green nanocomposites with tailored properties.

Diagnostic Performance of IgE Anti-Der p 10 to Identify Patients with Shrimp Allergy.

BACKGROUND: Patients with allergic rhinitis to house dust mites have an increased risk of shrimp allergy. Der p 10 is a candidate biomarker to predict the risk of shrimp allergy among allergic rhinitis patients. OBJECTIVES: The aim of this study was to evaluate the diagnostic performance of anti-Der p 10 IgE as a predictor of shrimp allergy. METHODS: A nested case-control study was carried out with eighty-six allergic rhinitis patients sensitized to mite (Dermatophagoides pteronyssinus) and shrimp (Litopenaeu vannamei). Cases and controls were defined by anti-Der p 10 IgE results. Oral challenge with shrimp was used as the gold standard for the evaluation of diagnostic performance. RESULTS: All shrimp oral challenge test (OCT)-positive patients were positive for IgE against Der p 10. The level of anti-Der p 10 IgE >1.2 kUA/mL had the best diagnostic performance (sensitivity 100%, specificity 65%) Conclusion: Anti-Der p 10 IgE is useful for predicting shrimp allergy diagnosis and could reduce the requirement of an OCT.

Synthesis and Processing of Nanomaterials Mediated by Living Organisms.

Nanomaterials offer exciting properties and functionalities. However, their production and processing frequently involve complex methods, cumbersome equipment, harsh conditions, and hazardous media. The capability of organisms to accomplish this using mild conditions offers a sustainable, biocompatible, and environmentally friendly alternative. Different nanomaterials such as metal nanoparticles, quantum dots, silica nanostructures, and nanocellulose are being synthesized increasingly through living entities. In addition, the bionanofabrication potential enables also the in situ processing of nanomaterials inside biomatrices with unprecedented outcomes. In this Minireview we present a critical state-of-the-art vision of current nanofabrication approaches mediated by living entities (ranging from unicellular to higher organisms), in order to expand this knowledge and scrutinize future prospects. An efficient interfacial interaction at the nanoscale by green means is within reach through this approach.

Inducible Polarized Secretion of Exosomes in T and B Lymphocytes.

Exosomes are extracellular vesicles (EV) of endosomal origin (multivesicular bodies, MVB) constitutively released by many different eukaryotic cells by fusion of MVB to the plasma membrane. However, inducible exosome secretion controlled by cell surface receptors is restricted to very few cell types and a limited number of cell surface receptors. Among these, exosome secretion is induced in T lymphocytes and B lymphocytes when stimulated at the immune synapse (IS) via T-cell receptors (TCR) and B-cell receptors (BCR), respectively. IS formation by T and B lymphocytes constitutes a crucial event involved in antigen-specific, cellular, and humoral immune responses. Upon IS formation by T and B lymphocytes with antigen-presenting cells (APC), the convergence of MVB towards the microtubule organization center (MTOC), and MTOC polarization to the IS, are involved in polarized exosome secretion at the synaptic cleft. This specialized mechanism provides the immune system with a finely-tuned strategy to increase the specificity and efficiency of crucial secretory effector functions of B and T lymphocytes. As inducible exosome secretion by antigen-receptors is a critical and unique feature of the immune system this review considers the study of the traffic events leading to polarized exosome secretion at the IS and some of their biological consequences.

Role of Microvesicles in the Spread of Herpes Simplex Virus 1 in Oligodendrocytic Cells.

Herpes simplex virus 1 (HSV-1) is a neurotropic pathogen that can infect many types of cells and establishes latent infections in the neurons of sensory ganglia. In some cases, the virus spreads into the central nervous system, causing encephalitis or meningitis. Cells infected with several different types of viruses may secrete microvesicles (MVs) containing viral proteins and RNAs. In some instances, extracellular microvesicles harboring infectious virus have been found. Here we describe the features of shedding microvesicles released by the human oligodendroglial HOG cell line infected with HSV-1 and their participation in the viral cycle. Using transmission electron microscopy, we detected for the first time microvesicles containing HSV-1 virions. Interestingly, the Chinese hamster ovary (CHO) cell line, which is resistant to infection by free HSV-1 virions, was susceptible to HSV-1 infection after being exposed to virus-containing microvesicles. Therefore, our results indicate for the first time that MVs released by infected cells contain virions, are endocytosed by naive cells, and lead to a productive infection. Furthermore, infection of CHO cells was not completely neutralized when virus-containing microvesicles were preincubated with neutralizing anti-HSV-1 antibodies. The lack of complete neutralization and the ability of MVs to infect nectin-1/HVEM-negative CHO-K1 cells suggest a novel way for HSV-1 to spread to and enter target cells. Taken together, our results suggest that HSV-1 could spread through microvesicles to expand its tropism and that microvesicles could shield the virus from neutralizing antibodies as a possible mechanism to escape the host immune response.IMPORTANCE Herpes simplex virus 1 (HSV-1) is a neurotropic pathogen that can infect many types of cells and establishes latent infections in neurons. Extracellular vesicles are a heterogeneous group of membrane vesicles secreted by most cell types. Microvesicles, which are extracellular vesicles which derive from the shedding of the plasma membrane, isolated from the supernatant of HSV-1-infected HOG cells were analyzed to find out whether they were involved in the viral cycle. The importance of our investigation lies in the detection, for the first time, of microvesicles containing HSV-1 virions. In addition, virus-containing microvesicles were endocytosed into CHO-K1 cells and were able to actively infect these otherwise nonpermissive cells. Finally, the infection of CHO cells with these virus-containing microvesicles was not completely neutralized by anti-HSV-1 antibodies, suggesting that these extracellular vesicles might shield the virus from neutralizing antibodies as a possible mechanism of immune evasion.

Use of patient-specific cutting blocks reduces blood loss after total knee arthroplasty.

Total knee arthroplasty (TKA) is associated with substantial blood loss. Sources of bleeding are the femoral and tibial intramedullary canals, which are violated during implantation using standard instrumentation. Patient-specific instrumentation (PSI) and computer-assisted surgery (CAS) do not require violation of the intramedullary canals. Therefore, we sought to assess the impact of these methods on blood loss and transfusion requirement. A retrospective cohort study was conducted in a series of 107 consecutive primary TKAs. The first group (n = 32) was operated with standard instrumentation, the second group (n = 35) with CAS and the third group (n = 40) with PSI. A tourniquet was used in all cases. Mean (standard deviation) calculated total blood loss was 442 (160), 750 (271) and 700 (401) ml for the PSI, CAS and standard instrumentation groups, respectively (p < 0.001), with no significant differences between CAS and standard instrumentation (p = 0.799). Significant differences were found in terms of transfusion requirements, with 12.5, 42.9 and 21.8% of the patients requiring transfusion (p = 0.010). Post hoc analysis revealed that only the difference between PSI and CAS were statistically significant (p = 0.003). In conclusion, PSI reduces blood loss when compared to both CAS and standard instrumentation TKA performed with the use of a tourniquet.

Chloral hydrate in pediatric magnetic resonance imaging: evaluation of a 10-year sedation experience administered by radiologists.

BACKGROUND: Chloral hydrate is a sedative that has been used for magnetic resonance imaging (MRI). OBJECTIVE: To evaluate the use, effectiveness and safety of chloral hydrate administered by radiologists for the sedation of children who require MRI procedures. MATERIALS AND METHODS: We retrospectively reviewed the clinical charts for all patients ages 0 - 10 years old who underwent sedation with chloral hydrate for MRI from January 2000 to December 2010. Demographic factors, dose information, indication for MRI, therapeutic failures and adverse reactions to the drug were reviewed. RESULTS: One thousand, seven hundred and three children (946 males, 757 females) with a median age of 2.5 years (range: 4 days - 9.91 years) received chloral hydrate. Moderate to deep sedation was achieved in 1,618/1,703 (95%) of the patients, 35/1,703 (2.1%) of the patients failed to achieve moderate to deep sedation, and 47/1,703 (2.8%) of the patients woke up during MRI examination. Adverse reactions were present in 31/1,703 (1.8%) of the patients. Three severe adverse reactions occurred (0.18%). A single dose of chloral hydrate (40-60 mg/kg) was administered to 1,477/1,703 patients (86.7%). An additional dose of chloral hydrate (10-20 mg/kg), given 15 min after the first dose or when the patient woke up during the MRI examination, was required in 226/1,703 patients (13.3%). The likelihood of requiring an additional dose in children older than 2 years was 2.2 times the likelihood compared to children younger than 2 years (OR = 2.2 [95%CI: 1.6-3.0]). The use of a reduced dose (<50 mg/kg) was not associated with a higher therapeutic failure rate (OR = 1.04 [95%CI 0.57-1.89]). CONCLUSION: Chloral hydrate is an appropriate sedation option for pediatric patients in MRI services when strict patient selection criteria are met. The use of a reduced dose does not affect the effectiveness of sedation. The lack of data regarding the presence of transient oxygen desaturation, the time to induce sedation and the exact duration of sedation are limitations of this study.

Assessment of cardiac volumes using an isotropic whole-heart dual cardiac phase sequence in pediatric patients.

PURPOSE: To evaluate the accuracy of a three-dimensional dual phase (3D DP) whole-heart technique for cardiac volumetric assessment in pediatric patients with cardiac abnormalities. MATERIALS AND METHODS: The institutional approved this study, and informed consent was obtained from patients or their guardians. This prospective study involved 31 pediatric patients (mean age, 7.9 years; range, 15 days to 15 years) for the assessment of cardiac abnormalities using cardiovascular MR. A standard protocol was performed for assessing cardiac anatomy and function. For evaluating the 3D DP technique, statistical comparison with a 2D cine multi-slice technique (2D steady-state free-precession [SSFP]) was performed using linear regression, intraclass correlation coefficient, and Bland Altman plots. RESULTS: Left (LV) and right (RV) ventricular cardiac volumes obtained with the 3D DP technique were in strong agreement with those obtained with the 2D SSFP technique for small and large ventricular volumes. The intraclass correlation coefficients (ICC) between both techniques were 0.992 for the LV end-diastolic volume (EDV), 0.983 for the LV end-systolic volume (ESV), 0.952 for the LV-systolic volume (SV), 0.992 for the RV-EDV, 0.992 for the RV-ESV, 0.928 for the RV-SV. Interobserver analysis indicated good reproducibility for both the 2D SSFP and the 3D DP techniques. CONCLUSION: The 3D DP technique provides as accurate cardiac volumes as the 2D SSFP technique in the pediatric population, but with the added benefits of easier data acquisition and detailed anatomical information of the whole heart and great vessels in a single free-breathing scan.

Nanocellulose: The Ultimate Green Aqueous Dispersant for Nanomaterials.

Nanocellulose, a nanoscale derivative from renewable biomass sources, possesses remarkable colloidal properties in water, mechanical strength, and biocompatibility. It emerges as a promising bio-based dispersing agent for various nanomaterials in water. This mini-review explores the interaction between cellulose nanomaterials (nanocrystals or nanofibers) and water, elucidating how this may enable their potential as an eco-friendly dispersing agent. We explore the potential of nanocellulose derived from top-down processes, nanocrystals, and nanofibers for dispersing carbon nanomaterials, semiconducting oxide nanoparticles, and other nanomaterials in water. We also highlight its advantages over traditional methods by not only effectively dispersing those nanomaterials but also potentially eliminating the need for further chemical treatments or supporting stabilizers. This not only preserves the exceptional properties of nanomaterials in aqueous dispersion, but may even lead to the emergence of novel hybrid functionalities. Overall, this mini-review underscores the remarkable versatility of nanocellulose as a green dispersing agent for a variety of nanomaterials, inspiring further research to expand its potential to other nanomaterials and applications.

Formin-like 1ß phosphorylation at S1086 is necessary for secretory polarized traffic of exosomes at the immune synapse in Jurkat T lymphocytes.

We analyzed here how formin-like 1 ß (FMNL1ß), an actin cytoskeleton-regulatory protein, regulates microtubule-organizing center (MTOC) and multivesicular bodies (MVB) polarization and exosome secretion at an immune synapse (IS) model in a phosphorylation-dependent manner. IS formation was associated with transient recruitment of FMNL1ß to the IS, which was independent of protein kinase C δ (PKCδ). Simultaneous RNA interference of all FMNL1 isoforms prevented MTOC/MVB polarization and exosome secretion, which were restored by FMNL1ßWT expression. However, expression of the non-phosphorylatable mutant FMNL1ßS1086A did not restore neither MTOC/MVB polarization nor exosome secretion to control levels, supporting the crucial role of S1086 phosphorylation in MTOC/MVB polarization and exosome secretion. In contrast, the phosphomimetic mutant, FMNL1ßS1086D, restored MTOC/MVB polarization and exosome secretion. Conversely, FMNL1ßS1086D mutant did not recover the deficient MTOC/MVB polarization occurring in PKCδ-interfered clones, indicating that S1086 FMNL1ß phosphorylation alone is not sufficient for MTOC/MVB polarization and exosome secretion. FMNL1 interference inhibited the depletion of F-actin at the central region of the immune synapse (cIS), which is necessary for MTOC/MVB polarization. FMNL1ßWT and FMNL1ßS1086D, but not FMNL1ßS1086A expression, restored F-actin depletion at the cIS. Thus, actin cytoskeleton reorganization at the IS underlies the effects of all these FMNL1ß variants on polarized secretory traffic. FMNL1 was found in the IS made by primary T lymphocytes, both in T cell receptor (TCR) and chimeric antigen receptor (CAR)-evoked synapses. Taken together, these results point out a crucial role of S1086 phosphorylation in FMNL1ß activation, leading to cortical actin reorganization and subsequent control of MTOC/MVB polarization and exosome secretion.

Extracellular vesicles and microvilli in the immune synapse.

T cell receptor (TCR) binding to cognate antigen on the plasma membrane of an antigen-presenting cell (APC) triggers the immune synapse (IS) formation. The IS constitutes a dedicated contact region between different cells that comprises a signaling platform where several cues evoked by TCR and accessory molecules are integrated, ultimately leading to an effective TCR signal transmission that guarantees intercellular message communication. This eventually leads to T lymphocyte activation and the efficient execution of different T lymphocyte effector tasks, including cytotoxicity and subsequent target cell death. Recent evidence demonstrates that the transmission of information between immune cells forming synapses is produced, to a significant extent, by the generation and secretion of distinct extracellular vesicles (EV) from both the effector T lymphocyte and the APC. These EV carry biologically active molecules that transfer cues among immune cells leading to a broad range of biological responses in the recipient cells. Included among these bioactive molecules are regulatory miRNAs, pro-apoptotic molecules implicated in target cell apoptosis, or molecules triggering cell activation. In this study we deal with the different EV classes detected at the IS, placing emphasis on the most recent findings on microvilli/lamellipodium-produced EV. The signals leading to polarized secretion of EV at the synaptic cleft will be discussed, showing that the IS architecture fulfills a fundamental task during this route.

Analysis of centrosomal area actin reorganization and centrosome polarization upon lymphocyte activation at the immunological synapse.

T cell receptor (TCR) and B cell receptor (BCR) stimulation of T and B lymphocytes, by antigen presented on an antigen-presenting cell (APC) induces the formation of the immunological synapse (IS). IS formation is associated with an initial increase in cortical filamentous actin (F-actin) at the IS, followed by a decrease in F-actin density at the central region of the IS, which contains the secretory domain. This is followed by the convergence of secretion vesicles towards the centrosome, and the polarization of the centrosome to the IS. These reversible, cortical actin cytoskeleton reorganization processes occur during lytic granule secretion in cytotoxic T lymphocytes (CTL) and natural killer (NK) cells, proteolytic granules secretion in B lymphocytes and during cytokine-containing vesicle secretion in T-helper (Th) lymphocytes. In addition, several findings obtained in T and B lymphocytes forming IS show that actin cytoskeleton reorganization also occurs at the centrosomal area. F-actin reduction at the centrosomal area appears to be associated with centrosome polarization. In this chapter we deal with the analysis of centrosomal area F-actin reorganization, as well as the centrosome polarization analysis toward the IS.

[Characterization of patients with anaphylaxis in a tertiary hospital in Medellin, Colombia (2009-2019)]. / Identificación de pacientes con anafilaxia en una institución de salud de tercer nivel de Medellín, Colombia (2009-2019).

OBJECTIVE: To characterize demographically and clinically the patients with anaphylaxis treated in a third level health institution in Medellin, Colombia. METHODS: A cross-sectional descriptive observational study was carried out, which includedpatients were diagnosed with anaphylaxis between 2009 and 2019. Information was retrieved from medical records through a collection instrument. Subsequently, a descriptive statistical analysis of proportions and measures of central tendency of the variables of interest was performed. RESULTS: A total of 1820 records were reviewed and data from 253 patients were included. Among the reported comorbidities, drug allergy was the most prevalent (28%). The most frequent manifestations of anaphylaxis were cutaneous and respiratory. Most of the cases presented basal tryptase values ≤ 11.4 ng/mL (94.7%). Different etiological agents (food, drugs, insects and latex) were reported, and their frequency varied according to age. Adrenaline, steroids, and antihistamines were the treatments of choice in 39.9, 34.3, and 39.9% of cases, respectively. CONCLUSIONS: The characteristics of anaphylaxis in a medical center in Colombia coincide with those reported in Latin American. The treatment of anaphylaxis is not standardized, which makes it necessary to educate the health personnel and develop national guidelines.

OBJECTIVO: Identificar las características clínicas y demográficas de pacientes con anafilaxia, atendidos en un hospital de tercer nivel de Medellín, Colombia. MÉTODOS: Estudio observacional, descriptivo, de corte transversal, al que se incluyeron pacientes con diagnóstico con anafilaxia entre 2009 y 2019. La información de los pacientes se obtuvo a partir de los expedientes clínicos, mediante un instrumento de recolección. Se realizó un análisis estadístico descriptivo, de proporciones y medidas de tendencia central de las variables de interés. RESULTADOS: Se revisaron 1820 expedientes y se incluyeron los datos de 253 pacientes. Los agentes etiológicos más frecuentes fueron: medicamentos (52.1%), alimentos (34.7%), picadura de insectos (13.8%) y agentes no especificados (17.7%). Las manifestaciones cutáneas y respiratorias fueron las más frecuentes asociadas con anafilaxia. El 94.7% de los casos tuvo concentraciones normales de triptasa. La adrenalina, los corticosteroides y antihistamínicos fueron los fármacos de elección en el 39.9, 34.3 y 39.9% de los casos, respectivamente. CONCLUSIONES: Las características de anafilaxia coinciden con las reportadas en la mayor parte de los estudios en Latinoamérica. Aunque existen guías mundiales de tratamiento de la anafilaxia, no suelen aplicarse de forma uniforme, lo que hace necesario adiestrar al personal de salud y desarrollar guías nacionales al respecto.

Effect of an action-research nutrition intervention on the Global Diet Quality Score of Colombian adolescents.

Strategies to address the nutritional needs of adolescent girls and young women often focus on supplementation. In this study, an action-research approach involving a nutrition education and entrepreneurship intervention was carried out among adolescent girls and young women in poor neighborhoods of Medellín, Colombia. The intervention group significantly increased its intake of several nutrients, including energy, protein, total fat, saturated fat, monounsaturated fat, polyunsaturated fat, cholesterol, dietary fiber, calcium, zinc, and vitamins A, B2, B3, B9, and C. A significant increase was observed in the intake of the Global Diet Quality Score (GDQS) healthy food groups (other fruits, other vegetables, legumes, high-fat dairy products), accompanied by a decrease in the consumption of some unhealthy food groups (sweets and ice creams). A multivariate regression controlling for age, socioeconomic status, occupation, Household Hunger Scale, mean probability of adequacy, physical activity, and body self-perception showed that the nutrition intervention improved the total GDQS by 33% in the intervention group-a substantial improvement notwithstanding the study group's precarious social and economic conditions. We conclude that nutrition education and entrepreneurship models based on this approach may improve the dietary profile of this population and reduce future pressures from nutrition-related chronic diseases.

Preparation of Cellulose Nanocrystals: Controlling the Crystalline Type by One-Pot Acid Hydrolysis.

Cellulose nanocrystals (CNCs) have aroused increasing interest owing to their renewable origin and excellent properties derived from their size and morphology. Based on their chain orientation, CNCs can be prepared as two main allomorphs (I or II). However, achieving pure CNC allomorphs still requires enhanced control on the CNCs synthesis process and improved understanding of the involved reaction parameters. In this work, we study in detail a set of parameters for CNC synthesis using one-pot acid hydrolysis and evaluate their influence on the outcome with respect to yield, purity, and repeatability. We also demonstrate that a fast, nondestructive, and accurate methodology based on dynamic light scattering is an efficient alternative to the usual structural analysis of the synthesis outcome. Finally, we provide an improved protocol to reliably obtain each allomorph with mass yields of 25% for type I and 40% for type II. Emphasis is put on the reduction of the environmental impact and the overall preparation time.

Informatics in radiology: use of CouchDB for document-based storage of DICOM objects.

Picture archiving and communication systems traditionally have depended on schema-based Structured Query Language (SQL) databases for imaging data management. To optimize database size and performance, many such systems store a reduced set of Digital Imaging and Communications in Medicine (DICOM) metadata, discarding informational content that might be needed in the future. As an alternative to traditional database systems, document-based key-value stores recently have gained popularity. These systems store documents containing key-value pairs that facilitate data searches without predefined schemas. Document-based key-value stores are especially suited to archive DICOM objects because DICOM metadata are highly heterogeneous collections of tag-value pairs conveying specific information about imaging modalities, acquisition protocols, and vendor-supported postprocessing options. The authors used an open-source document-based database management system (Apache CouchDB) to create and test two such databases; CouchDB was selected for its overall ease of use, capability for managing attachments, and reliance on HTTP and Representational State Transfer standards for accessing and retrieving data. A large database was created first in which the DICOM metadata from 5880 anonymized magnetic resonance imaging studies (1,949,753 images) were loaded by using a Ruby script. To provide the usual DICOM query functionality, several predefined "views" (standard queries) were created by using JavaScript. For performance comparison, the same queries were executed in both the CouchDB database and a SQL-based DICOM archive. The capabilities of CouchDB for attachment management and database replication were separately assessed in tests of a similar, smaller database. Results showed that CouchDB allowed efficient storage and interrogation of all DICOM objects; with the use of information retrieval algorithms such as map-reduce, all the DICOM metadata stored in the large database were searchable with only a minimal increase in retrieval time over that with the traditional database management system. Results also indicated possible uses for document-based databases in data mining applications such as dose monitoring, quality assurance, and protocol optimization.

T Lymphocyte and CAR-T Cell-Derived Extracellular Vesicles and Their Applications in Cancer Therapy.

Extracellular vesicles (EV) are a very diverse group of cell-derived vesicles released by almost all kind of living cells. EV are involved in intercellular exchange, both nearby and systemically, since they induce signals and transmit their cargo (proteins, lipids, miRNAs) to other cells, which subsequently trigger a wide variety of biological responses in the target cells. However, cell surface receptor-induced EV release is limited to cells from the immune system, including T lymphocytes. T cell receptor activation of T lymphocytes induces secretion of EV containing T cell receptors for antigen and several bioactive molecules, including proapoptotic proteins. These EV are specific for antigen-bearing cells, which make them ideal candidates for a cell-free, EV-dependent cancer therapy. In this review we examine the generation of EV by T lymphocytes and CAR-T cells and some potential therapeutic approaches of these EV.

Retinoblastoma: Review and new insights.

Retinoblastoma (Rb), the most frequent malignant intraocular tumor in childhood, is caused by mutations in the retinoblastoma gene (RB1) situated on chromosome 13q14.2. The incidence of retinoblastoma is approximately 1 in 17,000 live births with approximately 8,000 new cases diagnosed each year worldwide. Rb is the prototypical hereditary cancer in humans. Autosomal dominant inheritance is seen in 30-40% of cases whereas the non-inherited sporadic type accounts for the remaining 60-70%. Rb arises due to inactivation of both alleles of the Rb tumor suppressor gene, which results in a defective Rb protein (pRB) with subsequent cell cycle impairment and uncontrolled cell proliferation. Patients with Rb have survival rates higher than 95-98% in industrialized countries but mortality remains high in developing countries. For example, the mortality rate in Africa is 70%. In all cases of intraocular and extraocular retinoblastoma, there is a need for new therapies that are more effective and carry less risk of toxicity. The Bruckner test is a practical and easy test for the detection of Rb, this test consists of assessing the fundus reflex through the pupil (red reflex) in both eyes simultaneously with a bright coaxial light produced with the direct ophthalmoscope. Rb can be detected by the Bruckner test showing a pupil that shines white or "Leukocoria". Although the diagnosis of Rb remains essentially clinical, the newly identified biomarkers could contribute to early molecular detection, timely detection of micrometastases and establish new therapeutic options for Rb.

Role of Actin Cytoskeleton Reorganization in Polarized Secretory Traffic at the Immunological Synapse.

T cell receptor (TCR) and B cell receptor (BCR) stimulation by antigen presented on an antigen-presenting cell (APC) induces the formation of the immune synapse (IS), the convergence of secretory vesicles from T and B lymphocytes toward the centrosome, and the polarization of the centrosome to the immune synapse. Immune synapse formation is associated with an initial increase in cortical F-actin at the synapse, followed by a decrease in F-actin density at the central region of the immune synapse, which contains the secretory domain. These reversible, actin cytoskeleton reorganization processes occur during lytic granule degranulation in cytotoxic T lymphocytes (CTL) and cytokine-containing vesicle secretion in T-helper (Th) lymphocytes. Recent evidences obtained in T and B lymphocytes forming synapses show that F-actin reorganization also occurs at the centrosomal area. F-actin reduction at the centrosomal area appears to be involved in centrosome polarization. In this review we deal with the biological significance of both cortical and centrosomal area F-actin reorganization and some of the derived biological consequences.

Impact of the allergen-specific immunotherapy in pediatric patients with asthma treated at a health institution in Colombia / Efecto de la inmunoterapia con alérgenos específicos en pacientes pediátricos con asma atendidos en una institución de salud de Colombia

Introduction: Asthma is a chronic and potentially serious disease and 80% of the cases have an allergic etiology. In this sense, allergen-specific immunotherapy is an alternative that modulates the natural course of the disease. Objective: To evaluate the impact of immunotherapy in pediatric asthma patients treated at a health institution in Colombia. Materials and methods: We conducted an observational descriptive study with an analytical cross-sectional component. Sixty-two patients diagnosed with allergic asthma sensitized to dust mites and treated with at least 6 doses of mite immunotherapy were included. We assessed the impact of immunotherapy using the Asthma Control Test (ACT), the Global Initiative for Asthma (GINA) treatment scale, and spirometry values. Results: The ACT score before the start reported 30% of patients with uncontrolled asthma, 28% with good control, and 4% with totally controlled asthma. Of the patients with uncontrolled asthma, 46.7% achieved good control and 23.3% total control. Regarding patients' perception of improvement with the immunotherapy, 9.75% perceived a response of less than 50%, 45.2% one between 50% -90%, and 41.9% reported response equal to or greater than 90%. No significant changes in FEV1 values were found in spirometry. Conclusions: Significant changes in the ACT scores and the perception of disease improvement were observed in the population evaluated with specific mite immunotherapy, i.e., it had a positive impact on the natural course of the disease.

Introducción. El asma es una enfermedad crónica y potencialmente grave. El 80 % de los casos es de origen alérgico, por lo cual la inmunoterapia específica con alérgenos es una alternativa terapéutica que modula el curso natural de la enfermedad. Objetivo. Evaluar el impacto de la inmunoterapia en pacientes pediátricos con asma atendidos en una institución de salud de Colombia. Materiales y métodos. Se hizo un estudio observacional descriptivo con componente analítico de corte transversal. Se incluyeron 62 pacientes con diagnóstico de asma alérgica sensibilizados a ácaros del polvo y en tratamiento, mínimo, con seis dosis de inmunoterapia contra ácaros. El efecto del tratamiento se evaluó mediante la escala de puntuación del ACT (Asthma Control Test), la escala de tratamiento de la GINA (Global Initiative for Asthma) y la espirometría. Resultados. La puntuación de la prueba ACT antes del inicio de la inmunoterapia, correspondía a 30 % de pacientes con asma no controlada, 28 % con buen control y 4 % con asma totalmente controlada. Entre los pacientes con asma no controlada, el 46,7 % logró un buen control y el 23,3 % alcanzó un control total. En cuanto a la percepción de los pacientes sobre la mejoría con la inmunoterapia, el 9,75 % percibió una mejoría menor del 50 %, el 45,2 %, una entre el 50 y el 90 %, en tanto que el 41,9 % refirió una igual o mayor del 90 %. No se encontraron cambios significativos en los valores del volumen espiratorio forzado en un segundo (VEF1) en las espirometrías. Conclusiones. Se observaron cambios significativos en los puntajes del ACT y en la percepción de mejoría de la enfermedad en la población tratada con inmunoterapia específica para ácaros, es decir, que esta tendría un efecto beneficioso en el curso natural de la enfermedad.