Perspectives on the Trypanosoma cruzi-host cell receptor interaction

Chagas disease is caused by the parasite Trypanosoma cruzi. The critical initial event is the interaction of the trypomastigote form of the parasite with host receptors. This review highlights recent observations concerning these interactions. Some of the key receptors considered are those for thromboxane, bradykinin, and for the nerve growth factor TrKA. Other important receptors such as galectin-3, thrombospondin, and laminin are also discussed. Investigation into the molecular biology and cell biology of host receptors for T. cruzi may provide novel therapeutic targets

Detection of serum anti-B/B' UsnRNP antibodies in patients with connective tissue diseases by immunoblotting

Objective: To investigate the reliability of the immunoblot method in the detection of serum immunoreactivity towards the B/B' polypeptides of U small nuclear ribonucleoproteins (UsnRNP) and to assess the significance of these antibodies in connective tissue disease (CTD) patients. Methods: We tested the sera of 348 patients with CTD (101 SLE, 51 systemic sclerosis, 53 primary Sjogren's syndrome, 27 poly/dermatomyositis, 15 rheumatoid arthritis and 101 overlap CTD), of 31 matched healthy subjects and 13 patients with primary Epstein-Barr virus (EBV) infection with high titre IgG anti-EBV antibodies. IgG anti-UsnRNP antibodies were determined by immunoblotting on nuclear extract from Raji cells (an EBV-immortalised human B lymphoid cell line) and Jurkat cells (a human T lymphoid cell line). Anti-dsDNA antibodies were detected by indirect immunofluorescence on Crithidia luciliae and anti-ENA by counterimmunoelectrophoresis. Anti-dsDNA activity and avidity were measured in SLE sera by ELISA with Scatchard analysis. Results were statistically analysed by chi-square and Mann-Whitney tests. Results: A high frequency of anti-B/B' antibodies was found in the sera of CTD patients, confined to SLE (54.4%) and overlap CTD with SLE features (55,2%). Anti-B/B' immune reactivity was closely associated with other anti-UsnRNP specificities, gel precipitating anti-nRNP and anti-P antibodies. Nine out of 15 (60%) anti-B/B' positive/anti-ENA negative lupus sera on Raji blots were confirmed to be positive also on Jurkat blots. The sera from patients with EBV infection provided, on Raji blots, completely different band patterns from those obtained with auto-immune sera. Conclusions. The Sm B/B' proteins are the predominant or, at least, the most frequently targeted antigens of the UsnRNP auto-immune response in SLE and "lupus-like" overlap CTD. Moreover, anti-B/B' is diagnostically specific for CTD with SLE features. Immunoblotting on human B lymphoid cells is a reliable method, in terms of sensitivity and specificity, for the detection of anti-Sm B/B' antibodies

QuantiMus: A Machine Learning-Based Approach for High Precision Analysis of Skeletal Muscle Morphology.

Skeletal muscle injury provokes a regenerative response, characterized by the de novo generation of myofibers that are distinguished by central nucleation and re-expression of developmentally restricted genes. In addition to these characteristics, myofiber cross-sectional area (CSA) is widely used to evaluate muscle hypertrophic and regenerative responses. Here, we introduce QuantiMus, a free software program that uses machine learning algorithms to quantify muscle morphology and molecular features with high precision and quick processing-time. The ability of QuantiMus to define and measure myofibers was compared to manual measurement or other automated software programs. QuantiMus rapidly and accurately defined total myofibers and measured CSA with comparable performance but quantified the CSA of centrally-nucleated fibers (CNFs) with greater precision compared to other software. It additionally quantified the fluorescence intensity of individual myofibers of human and mouse muscle, which was used to assess the distribution of myofiber type, based on the myosin heavy chain isoform that was expressed. Furthermore, analysis of entire quadriceps cross-sections of healthy and mdx mice showed that dystrophic muscle had an increased frequency of Evans blue dye+ injured myofibers. QuantiMus also revealed that the proportion of centrally nucleated, regenerating myofibers that express embryonic myosin heavy chain (eMyHC) or neural cell adhesion molecule (NCAM) were increased in dystrophic mice. Our findings reveal that QuantiMus has several advantages over existing software. The unique self-learning capacity of the machine learning algorithms provides superior accuracy and the ability to rapidly interrogate the complete muscle section. These qualities increase rigor and reproducibility by avoiding methods that rely on the sampling of representative areas of a section. This is of particular importance for the analysis of dystrophic muscle given the "patchy" distribution of muscle pathology. QuantiMus is an open source tool, allowing customization to meet investigator-specific needs and provides novel analytical approaches for quantifying muscle morphology

Herramientas moleculares aplicadas al estudio de aguas para el consumo humano, comunidad El Cacao, Nicaragua

Se determinó la presencia de contaminantes microbianos en aguas de consumo humano de la comunidad El Cacao, Mosonte, Nueva Segovia. El análisis se realizó tanto por métodos microbiológicos como por ví­a molecular analizando su interrelación con las enfermedades que se observan en la comunidad. Se obtuvo la presencia de coliformes fecales, totales y Escherichia coli desde la captación hasta el tanque de almacenamiento. Los aislados identificados pertenecen a las bacterias del tipo Alcaligenes y Paenalcaligenes, además de Stenotrophomonas y Serratia. Las cuales son bacterias acuáticas y están asociadas a diversas enfermedades. Además se identificó lapresencia de Aspergillus que han sido bien reportados en diversas enfermedades humanas

Diagnostic efficacy of the ELISA test for the detection of deamidated anti-gliadin peptide antibodies in the diagnosis and monitoring of celiac disease

Volcano plot of differential gene expression in IZE_Suc vs IZE, ZE_5w vs IZE_Suc and SE_5w vs IZE. (DOCX 256 kb

IgE antibody repertoire in nasal secretions of children and adults with seasonal allergic rhinitis: a molecular analysis

Background: There is growing interest both in testing IgE in nasal secretions (NS) and in molecular diagnosis of seasonal allergic rhinitis (SAR). Yet, the reliability of nasal IgE detection with the newest molecular assays has never been assessed in a large cohort of pollen allergic patients. Objective: To investigate with microarray technology and compare the repertoires of specific IgE (sIgE) antibodies in NS and sera of a large population of children and adults with SAR. Methods: Nasal secretions were collected with an absorbent device (Merocel 2000®, Medtronic) and a minimal dilution procedure from 90 children and 71 adults with SAR. Total IgE (tIgE) (ImmunoCAP, Thermo Fisher Scientific (TFS)) and sIgE antibodies against 112 allergen molecules (ISAC-112, TFS) were measured in NS and serum. Results: Nasal sIgE was detectable in 68.3% of the patients. The detected nasal sIgE antibodies recognized airborne (88%), vegetable (10%), and animal food or other (<1%) allergen molecules. The prevalence and average levels of sIgE in NS and serum were highly interrelated at population level. A positive nasal sIgE antibody to a given molecule predicted the detection of the same antibody in the patient's serum with a specificity of 99.7% and a sensitivity of 40%. Conclusions: The concentration of sIgE is much lower in nasal secretions than in the serum. sIgE assays with very high analytical sensitivity and sampling methods with minimal dilution will be therefore needed to validate nasal secretions as alternative to serum in testing the sIgE repertoire

Genome-Scale CRISPR-Mediated Control of Gene Repression and Activation

While the catalog of mammalian transcripts and their expression levels in different cell types and disease states is rapidly expanding, our understanding of transcript function lags behind. We present a robust technology enabling systematic investigation of the cellular consequences of repressing or inducing individual transcripts. We identify rules for specific targeting of transcriptional repressors (CRISPRi), typically achieving 90%–99% knockdown with minimal off-target effects, and activators (CRISPRa) to endogenous genes via endonuclease-deficient Cas9. Together they enable modulation of gene expression over a ∼1,000-fold range. Using these rules, we construct genome-scale CRISPRi and CRISPRa libraries, each of which we validate with two pooled screens. Growth-based screens identify essential genes, tumor suppressors, and regulators of differentiation. Screens for sensitivity to a cholera-diphtheria toxin provide broad insights into the mechanisms of pathogen entry, retrotranslocation and toxicity. Our results establish CRISPRi and CRISPRa as powerful tools that provide rich and complementary information for mapping complex pathways

Heterogeneous validity of daily data on symptoms of seasonal allergic rhinitis recorded by patients using the e-diary AllergyMonitor®

Background: Patient-generated symptom and medication scores are essential for diagnostic and therapeutic decisions in seasonal allergic rhinitis (SAR). Previous studies have shown solid consistencies between different scores at population level in real-life data and trials. For clinicians, the evaluation of individual data quality over time is essential to decide whether to rely on these data in clinical decision-making. Objective: To analyze the consistency of different symptom (SS) and symptom medication scores (SMSs) at individual level in two study cohorts with different characteristics and explore individual patient trajectories over time. Methods: Within the pilot phase of the @IT.2020 project on diagnostic synergy of mobile health and molecular IgE assessment in patients with SAR, we analyzed data of 101 children and 93 adults with SAR and instructed them to record their symptoms and medication intake daily via the mobile app AllergyMonitor®. We then assessed the correlation between different SMS and a visual analogue scale (VAS) on the impact of allergy symptoms on daily life at population and individual level. Results: At population level, the Rhinoconjunctivitis total symptom score (RTSS) correlated better with VAS than the combined symptom and medication score (CSMS). At individual level, consistency among RTSS and VAS was highly heterogeneous and unrelated to disease severity or adherence to recording. Similar heterogeneity was observed for CSMS and VAS. Conclusions: The correlation of clinical information provided by different disease severity scores based on data collected via electronic diaries (e-diaries), is sufficient at population level, but broadly heterogeneous for individual patients. Consistency of the recorded data must be examined for each patient before remotely collected information is used for clinical decision making

Correlation between IgA tissue transglutaminase antibody ratio and histological finding in celiac disease.

OBJECTIVES: Positivity of both immunoglobulin A anti-tissue transglutaminase (TTG) and anti-endomysium antibodies (EMA) has a positive predictive value of nearly 100% for celiac disease (CD). The objective of the present study was to evaluate whether patients of any age, with high pretest probability of CD and high titre of anti-TTG and EMA positivity, have a high probability of intestinal damage and may not require the biopsy for final diagnosis. METHODS: A retrospective analysis of 412 consecutively referred patients, age range 10 months to 72 years, who underwent small-bowel biopsy for suspicion of CD and positivity to both anti-TTG and EMA, was performed at 4 Italian centers. Biopsies were evaluated independently by 2 pathologists using Marsh modified classification; in cases of dissimilar results, a third pathologist examined the biopsy. The final histological finding diagnosis was expressed as the prevalent or highest score assigned by the pathologist board. RESULTS: Three hundred ninety-six patients (96.1%) had histological findings consistent with CD (grade 2 and 3a, 3b, or 3c of modified Marsh classification). An anti-TTG ratio ≥ 7 was able to identify with the 3 assays used (Celikey, anti-TTG immunoglobulin A, EuTTG) all of the patients with significant mucosal damage (Marsh ≥ 2) independent of age and sex; specificity and positive predictive value were 100%. An anti-TTG ratio >20 was more specific (99.8%) for identification of patients with villous atrophy (Marsh 3 a, b, or c). CONCLUSIONS: Patients with positivity of anti-TTG ≥ 7-fold cutoff, confirmed by positivity to EMA, have a high-degree probability of duodenal damage. In selected conditions, a duodenal biopsy may be avoided and a confirmed greatly positive anti-TTG result could be the basis to prescribe a gluten-free diet