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Background: Helicobacter pylori has been linked to several diseases such as chronic urticaria, gastritis, and type 1 gastric neuroendocrine tumors (type 1 gNET). Although these diseases seem to have different mechanisms, their relationship with H. pylori suggests a common inflammatory pathway. Objective: To identify potential cross-reactive antigens between H. pylori and humans involved in chronic urticaria and type 1 gNET. Methods: Alignment was carried out among human proteins associated with urticaria (9 proteins), type 1 gNET (32 proteins), and H. pylori proteome. We performed pairwise alignment among the human and H. pylori antigens with PSI-BLAST. Modeling based on homology was done with the Swiss model server and epitope prediction with the Ellipro server. Epitopes were located on a 3D model using PYMOL software. Results: The highest conserved sequence was found between the human HSP 60 antigen and the H. pylori chaperonin GroEL with an identity of 54% and a cover of 92%, followed by the alpha and gamma enolases and two H. pylori phosphopyruvate hydratase, both with an identity and cover of 48% and 96%, respectively. The H/K ATPase (Chain A) showed high identity with two H. pylori proteins (35.21% with both P-type ATPase), but with low cover (only 6%). We observed eight linear and three discontinuous epitopes for human HSP 60 and three lineal and one discontinuous epitope for both alpha-enolase and gamma enolase, high conserved with H. pylori sequences. Conclusion: Some type 1 gNET antigens shared potential cross-reactive epitopes with H. pylori proteins, suggesting that molecular mimicry could be a mechanism that explains the relationship between the infection and this disease. Studies evaluating the functional impact of this relationship are needed. [ABSTRACT FROM AUTHOR]

Objective: To identify through In Silico analysis the possible molecular mimicry between Der p 23 and antigens from allergenic sources. Methods: Identity was sought between Der p 23 and proteins from the mite families Pyroglyphidae, Acaridae, Chortoglyphidae and Echimyopodidae, through PSI-BLAST and They used PRALINE and EMBOSS for the alignments. Antigens with resolved experimental structure were obtained from Protein Data Bank and those not reported were generated using Swiss Model server and ALPHAFOLD 2. Epitope prediction was carried out with the Ellipro server and Pymol 2.3 was used to visualize the 3D models. Results: The analysis between Pyroglyphidae allergens and Der p 23 showed identity with the endochitinase-like protein of D. pteronyssinus, and the type 2 chitin binding domain of D. farinae, with identities between 85 and 100%, with coverage of 100%, and 75% respectively. The allergens Der f 23 and Der p 23 of D. farinae and D. pteronyssinus had 100% coverage with identities of 85.42% and 79.59%, respectively. Among the allergens of Tyrophagus putrescentiae, binding to chitin, oviduct-specific glycoprotein and Cda4p were included, which had identity values corresponding to 40%, 42.22% and 34.78%, with coverage values that did not exceed the 55%. No results were found for Chortoglyphidae and Echimyopodidae. Conclusion: There is molecular mimicry and structural homology between Der P 23 and allergens from allergic sources of the Pyroglyphidae and Acaridae families. Potential epitopes were identified in Der p 23, which could present cross-reactivity with the proteins of the allergenic sources studied, which must be demonstrated in In vitro and In vivo studies. In vitro and in vivo work is needed to demonstrate the results obtained in the In Silico analysis. [ABSTRACT FROM AUTHOR]

Introduction: Cardiovascular diseases are the result of genetic and environmental interaction that conditions the integrity of the heart and blood vessels. Risk factors include infections. The inflammatory response against the infectious agent is a trigger of autoimmune cardiovascular diseases, due to the similarity between the pathogen proteins and human antigens, since the immune response can present cross-reactivity caused by molecular mimicry. Methods: We performed a search for pathogens involved in autoimmune heart diseases and autoantigens associated with these diseases in the Pubmed and Google Scholar search engines. Identity between proteins was performed through global alignments using PSI-BLAST. The 3D structures of the proteins were obtained by Uniprot or NCBI and, if they were not found, the structures were modeled by homology, using the Swiss Model server. Epitope prediction was performed through Ellipro, and the Immunological Epitope Database (IEDB). In addition, the PYMOL program was used for the visualization of proteins in 3D, and the positioning of the epitopes in the structure. Results: Ten cardiovascular proteins showed identity (30-88.24%) in their amino acid sequences with antigens from ten pathogens. Actin proteins and heat shock protein (HSP) families presented higher levels of identity with Trypanosoma Cruzi, Cryptococcus neoformans and Chlamydia trachomatis, 71.47%, 88.24% and 80. 61%, respectively. Other pathogens, such as Streptococcus pyogenes, Bacillus sp, Magnetospirillum gryphiswaldense, Helicobacter pylori and Chlamydia pneumoniae, presented moderate identity with a maximum value of 65.79%. Conclusion: Human actin and HSPs share a high degree of conservation with epitopes from various microorganisms, such as bacteria, fungi, and protozoa; suggesting molecular mimicry and cross-reactivity as mechanisms for the development of atherosclerosis, rheumatic heart disease, myocarditis, and Chagas heart disease. In vitro and in vivo work is needed to demonstrate the results obtained in the In Silico analysis. [ABSTRACT FROM AUTHOR]

Background: Allergen immunotherapy has demonstrated usefulness in the management of allergic diseases such as asthma, allergic rhinitis and conjunctivitis. However, little is known about its effectiveness in vernal keratoconjunctivitis (VKC), a disease mediated by IgE and lymphocytes, that can cause loss of visual acuity in a permanent way. Objective: To describe safety and effectiveness of allergen immunotherapy in a group of patients with VKC. Patients and Methods: From a sample of 575 patients sensitized to house dust mites, who received ultra-rush immunotherapy for asthma, allergic rhinoconjuctivitis or atopic dermatitis, 28 patients with VKC were selected and a retrospective analysis was performed with the evaluation of factors related to safety, pharmacological treatment and clinical response to immunotherapy. Results: Twenty eight patients with VKC who received allergen immunotherapy were studied. There were 21 men and 7 women, with an average age of 11 years. A total of 490 doses were administered (35 for build-up and 455 for maintenance) for different periods. The average number of doses per patient was 17. There were no local or systemic reactions. Seventy one percent of the patients presented a clear reduction in the use of medications, with an improvement in symptoms 89% and physical findings 68%. Conclusions: Allergen immunotherapy seems to be a safe and efficient treatment for patients with VKC, and can contribute along with pharmacological management to the improvement of symptoms and reduction in the use of medications. [ABSTRACT FROM AUTHOR]

Introduction: Since infants are not able to express their feelings during the preverbal stage of development, neonatal pain rating scales are good tools for nurses to use in clinical practice. Objective: To describe valid and reliable scales used in nursing practice to assess neonatal pain. Materials and Methods: An integrative review of articles published since 1990 was conducted from 2019 to 2020. The databases consulted were PubMed, Lilacs, ProQuest, ScienceDirect, Embase, VHL, Scopus, and Google Scholar metasearch engine. Twenty-two articles that met the inclusion criteria were analyzed. Results: Unidimensional and multidimensional instruments were found for assessing acute and prolonged pain in preterm and term neonates. Discussion: This integrative review provides healthcare professionals, especially nurses, with a conceptual basis for implementing clinical pain assessment tools according to gestational age, duration of pain, and type of indicator. Conclusions: According to the knowledge and characteristics of the scales, it is not possible to clearly establish the most appropriate one for general use or a gold standard; the selection will depend on different criteria, such as the type of stimulus, gestational age, and the newborn's context. [ABSTRACT FROM AUTHOR]

Background: Allergen sensitization is the first step in the onset of allergic diseases. Sensitizing sources may vary among geographic region but identification is needed to develop effective treatment as specific avoidance measures and immunotherapy. Objective: To determine the prevalence of sensitization to several sources of aeroallergens by prick skin tests, in a group of patients with rhinitis, conjunctivitis, asthma or atopic dermatitis in a tropical city. Methods: We reviewed the medical records of patients and their results of skin prick tests with aeroallergens, including Dermatophagoides pteronyssinus and Dermatophagoides farina, during the period of January 2008 to December 2011. Results. Three hundred allergic patients with sensitization to 30 different allergens were included. House dust mites (78%), dog dander (47%) and cockroach (21.5%) were the most frequent positive allergens. We observed a significative sensitization pattern with house dust mites, dog dander, molds and piggeon droppings, associated with systemic allergic sensitization. Conclusions: As we expect, mites are the main source of sensitization in Medellin. However, other sources common in other regions such as the pollen grains are rare. The identification of the sources could help to predict in young children allergic phenotypes. [ABSTRACT FROM AUTHOR]

Background. Immunotherapy has proven to be an useful tool in the management of allergic respiratory diseases; however, little has been studied in atopic dermatitis. Objective. To evaluate the clinical and immunological impact of immunotherapy with mites allergen extracts in atopic dermatitis. Methods. Patients with atopic dermatitis were assigned with computer-generated randomization to either of the following groups: (a) controls received only topical treatment with steroids and/or tacrolimus and (b) actively treated patients received topical treatment plus immunotherapy. Levels of serum total IgE, mites-specific IgE and IgG4 were assessed at study start and after one year of immunotherapy. Results. 31 patients in the active group and 29 in the control group completed the study. Symptoms and medication scores were significantly reduced in the active group after six months. Three patients in the control group showed new sensitizations to mites, while 3 patients in the active group showed neosensitization to shrimp with negative oral food challenge. We observed significant increase ofmites-specific IgG4 levels in active group. Conclusion. Specific allergen immunotherapy induced a tolerogenic IgG4 response to mite allergens associated with favorable clinical effects in atopic dermatitis patients. [ABSTRACT FROM AUTHOR]

A mixed spin-1 and spin-2 Ising ferrimagnetic system is investigated on a square lattice of spins S = ± 2 , ± 1 , 0 and Q = ± 1 , 0 in the presence of an h ′ external magnetic field, such that S and Q are nearest-neighbors antiferromagnetically coupled. Using Monte Carlo simulations we calculate the finite temperature phase diagrams of the magnetization and the specific heat. We consider ferromagnetic interactions between next-nearest neighbors, S spins ( J 2 ′ ), as well as between the Q spins ( J 3 ′ ), and crystal field and external magnetic field interactions at each point of the lattice. Under these conditions the system exhibits spin compensation temperatures and a first-order reentrant behavior in a certain range of the parameters of the Hamiltonian. We analyze the behavior of the critical and compensation temperatures, as well as the first order phase transition temperatures, with the external magnetic and crystal fields, and the next-nearest neighbors interaction between S spins. We found that the existence of compensation temperatures and a first order phase transition depends on the strength of h ′ , J 2 ′ and D ′ . [ABSTRACT FROM AUTHOR]