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1.
Vilar-Compte Mireya Gaitán-Rossi Pablo Félix-Beltrán Lucía Bustamante Arturo V. 《Journal of immigrant and minority health / Center for Minority Public Health》2022,24(1):65-77
Journal of Immigrant and Minority Health - COVID-19 has disproportionally affected underrepresented minorities (URM) and low-income immigrants in the United States. The aim of the study is to... 相似文献
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Nikhat Parveen Mark C. Fernandez Austin M. Haynes Rui-Li Zhang B. Charmie Godornes Arturo Centurion-Lara Lorenzo Giacani 《Vaccine》2019,37(13):1807-1818
Background
Syphilis is resurgent in many developed countries and still prevalent in developing nations. Current and future control campaigns would benefit from the development of a vaccine, but although promising vaccine candidates were identified among the putative surface-exposed integral outer membrane proteins of the syphilis spirochete, immunization experiments in the rabbit model using recombinant antigens have failed to fully protect animals upon infectious challenge. We speculated that such recombinant immunogens, purified under denaturing conditions from Escherichia coli prior to immunization might not necessarily harbor their original structure, and hypothesized that enhanced protection would result from performing similar immunization/challenge experiments with native antigens.Methods
To test our hypothesis, we engineered non-infectious Borrelia burgdorferi strains to express the tp0897 (tprK) and tp0435 genes of Treponema pallidum subsp. pallidum and immunized two groups of rabbits by injecting recombinant strains intramuscularly with no adjuvant. TprK is a putative integral outer membrane protein of the syphilis agent, while tp0435 encodes the highly immunogenic T. pallidum 17-kDa lipoprotein, a periplasmic antigen that was also shown on the pathogen surface. Following development of a specific host immune response to these antigens as the result of immunization, animals were challenged by intradermal inoculation of T. pallidum. Cutaneous lesion development was monitored and treponemal burden within lesions were assessed by dark-field microscopy and RT-qPCR, in comparison to control rabbits.Results
Partial protection was observed in rabbits immunized with B. burgdorferi expressing TprK while immunity to Tp0435 was not protective. Analysis of the humoral response to TprK antigen suggested reactivity to conformational epitopes.Conclusions
Immunization with native antigens might not be sufficient to obtain complete protection to infection. Nonetheless we showed that non-infectious B. burgdorferi can be an effective carrier to deliver and elicit a specific host response to T. pallidum antigens to assess the efficacy of syphilis vaccine candidates. 相似文献4.
Paula López-Sánchez José Portolés Leyre Martín Rodríguez Fernando Tornero Arturo José Ramos Martín-Vegue José Antonio Herrero Juan Luis Cruz Bermúdez 《Nefrología : publicación oficial de la Sociedad Espa?ola Nefrologia》2019,39(6):653-663
Introduction and objectivesChronic kidney disease has a high prevalence and economic impact, and an increased risk of hospitalization. Although there are public regional and country registries, we have not found references to estimate the impact of renal replacement therapy (RRT) on hospital admissions.MethodsWe obtained authorization from the ethics committee and health authorities to integrate the REMER [Madrid Kidney Disease Registry] (2013-2014) and Minimum Basic Data Set (2013-2015) databases and to analyze the admissions during the first year of RRT.Results767 patients started RRT in all the hospitals of our region across all RRT modalities. More than a third of the patients start dialysis during a hospital admission. This unplanned start, more common in HD than PD, shows relevant differences in patient profile or admission characteristics.Without considering this initial episode, almost 60% of patients were admitted during their first year. The hospitalization rate was 1.2 admissions/patient, higher in HD than in TX or PD; the mean length of stay was 8.6 days.The estimated cost of admissions during the first year is €12,006/patient. Our analysis ensures the exhaustive inclusion of all episodes and accurate estimation based on the discharge form.ConclusionThe impact of RRT on hospitals has been underestimated and is very relevant when calculating the total cost of RRT. Results from other countries cannot be extrapolated due to differences in the health system and patient profile. The integration of clinical databases could open up an opportunity that needs only institutional support for its development. 相似文献
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Jose Arturo Molina-Mora Diana Chinchilla-Montero Carolina Castro-Pea Fernando García 《Medicine》2020,99(49)
Two-dimensional gel electrophoresis (2D-GE) is an indispensable technique for the study of proteomes of biological systems, providing an assessment of changes in protein abundance under various experimental conditions. However, due to the complexity of 2D-GE gels, there is no systematic, automatic, and reproducible protocol for image analysis and specific implementations are required for each context. In addition, practically all available solutions are commercial, which implies high cost and little flexibility to modulate the parameters of the algorithms. Using the bacterial strain, Pseudomonas aeruginosaAG1 as a model, we obtained images from 2D-GE of periplasmic protein profiles when the strain was exposed to multiple conditions, including antibiotics. Then, we proceeded to implement and evaluate an image analysis protocol with open-source software, CellProfiler. First, a preprocessing step included a bUnwarpJ-Image pipeline for aligning 2D-GE images. Then, using CellProfiler, we standardized two pipelines for spots identification. Total spots recognition was achieved using segmentation by intensity, whose performance was evaluated when compared with a reference protocol. In a second pipeline with the same program, differential identification of spots was addressed when comparing pairs of protein profiles. Due to the characteristics of the programs used, our workflow can automatically analyze a large number of images and it is parallelizable, which is an advantage with respect to other implementations. Finally, we compared six experimental conditions of bacterial strain in the presence or absence of antibiotics, determining protein profiles relationships by applying clustering algorithms PCA (Principal Components Analysis) and HC (Hierarchical Clustering). 相似文献
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Juan-Carlos Hernández-Boluda Eduardo Arellano-Rodrigo Francisco Cervantes Alberto Alvarez-Larrán Montse Gómez Pere Barba María-Isabel Mata José-Ramón González-Porras Francisca Ferrer-Marín Valentín García-Gutiérrez Elena Magro Melania Moreno Ana Kerguelen Manuel Pérez-Encinas Natàlia Estrada Rosa Ayala Carles Besses Arturo Pereira 《Annals of hematology》2015,94(6):911-918
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Rosario Gulias-Cañizo Anell Lagunes-Guillén Arturo González-Robles Erika Sánchez-Guzmán Federico Castro-Muñozledo 《Burns : journal of the International Society for Burn Injuries》2019,45(2):398-412
Background
Since recent reports have shown that (-)-Epigallocatechin-3-gallate (EGCG) could be used for treating proliferative and inflammatory disorders, we explored its use for the management of corneal chemical burns.Materials and methods
Initially, EGCG was assayed on the rabbit corneal epithelial cell line RCE1(5T5) to establish the best testing conditions, and to avoid unwanted outcomes in the experimental animals. Then, we studied its effects on cell proliferation, cell cycle progression and cell differentiation. Afterwards, we instilled EGCG in experimental grade II corneal alkali burns in mice, three times a day up to 21 days, and evaluated by slit lamp examination and histological sections of corneal epithelial, corneal endothelial and stromal edema, as well as the presence of inflammatory cells and neovascularization.Results
EGCG reduced cell growth and led to a decline in the proportion of proliferative cells in a concentration dependent manner. At 10 μM, EGCG promoted cell differentiation, an effect not related with apoptosis or cytotoxicity. When 10 μM EGCG was instilled in corneal alkali burns in mice three times a day up to 21 days, EGCG significantly reduced corneal opacity and neovascularization. The improved clinical appearance of the cornea was associated to a controlled epithelial growth; epithelial morphology was similar to that observed in normal epithelium and contrasted with the hyperproliferative, desquamating epithelium observed in control burn wounds. EGCG reduced corneal, stromal and endothelial edema, and wound inflammation.Conclusion
This work constitutes the first evidence for the use of EGCG in the acute phase of a corneal alkali burn, representing a possible novel alternative to improve patient outcomes as an add-on therapy. 相似文献9.
Francisca Cristi Guillermo Perez‐Mateluna Cristin Vera‐Kellet Sergio Silva‐Valenzuela Carolina Iturriaga Rodrigo Hoyos‐Bachiloglu Cristin Navarrete‐Dechent Lorena Cifuentes Carlos A. Camargo Alexis M. Kalergis Arturo Borzutzky 《Experimental dermatology》2019,28(3):308-311
Vitamin D (VD) deficiency has been associated with increased incidence and severity of atopic dermatitis (AD), but the mechanisms through which VD may ameliorate AD are unclear. We compared the phenotypic characteristics of circulating myeloid and plasmacytoid dendritic cells (mDCs and pDCs, respectively) of children with AD vs healthy controls (HC) and evaluated if VD can modulate the allergic phenotype of circulating DCs in AD patients. Although there was no difference in frequency of circulating DCs between groups, among children with AD there was an inverse correlation between SCORAD and circulating total DCs and mDCs. In AD, serum IgE concentration correlated with FcεRI and surface‐bound IgE expression on mDCs and pDCs; pDCs expressing FcεRI and IgE were significantly increased compared to HC. Ex vivo, 1,25(OH)2D3 significantly decreased FcεRI expression on mDCs and surface‐bound IgE on mDCs and pDCs. Oral VD supplementation reduced expression of surface‐bound IgE on pDCs in children with AD. In summary, VD decreases the allergic phenotype of circulating DCs in children with AD, a potential mechanism for how VD supplementation may improve AD severity. Future studies are needed to further assess the role of VD supplementation as an immunomodulatory therapy for AD. 相似文献
10.
Emilio Domínguez‐Salazar Gabriela Hurtado‐Alvarado Fernanda Medina‐Flores Javik Dorantes Oscar Gonzlez‐Flores Arturo Contis‐Montes de Oca Javier Velzquez‐Moctezuma Beatriz Gmez‐Gonzlez 《Journal of sleep research》2020,29(3)
Sleep loss increases blood–brain barrier permeability. As the blood–brain barrier and the blood–tissue barriers in the reproductive tract (blood–testis and blood–epididymis barriers) share common characteristics, we hypothesized that sleep restriction may also modify their barrier function. Previous reports showed that sleep loss decreased sperm viability and progressive fast mobility, which may be a consequence of altered blood–testis and blood–epididymis barrier. Therefore, we quantified changes in blood–testis and blood–epididymis barrier after sleep loss and related them to male fertility. Adult male Wistar rats were sleep restricted using the multiple‐platform technique in a protocol of 20 hr daily sleep deprivation plus 4 hr of sleep recovery in the home‐cage. At the 10th day, barrier permeability assays were performed with Na‐fluorescein, 10 kDa Cascade blue‐dextrans and Evans blue, and the expression of tight junction proteins, actin and androgen receptor was quantified. At the 10th day of sleep restriction and after sleep recovery days 1–7, males were placed with sexually receptive females, sexual behaviour was tested, and the percentage of pregnancies was calculated. Sleep restriction increased the barrier permeability to low‐ and high‐molecular‐weight tracers, and decreased the expression of tight junction proteins, actin and androgen receptor. Concomitantly, sleep restriction reduced the percentage of ejaculating males and the number of pregnancies. Sleep recovery for 2–3 days progressively re‐established fertility, as indicated by a higher percentage of ejaculating males and impregnated females. In conclusion, chronic sleep loss alters fertility concomitantly with the disruption of the blood–tissue barriers at the reproductive tract, the mechanism involves androgen signalling. 相似文献