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BACKGROUND: Prolonged hospitalization due to the COVID-19 pandemic gathered risk factors for developing invasive candidiasis. AIM: To describe Candida spp. isolated from patients with clinical suspicion of COVID treated in a public hospital specialized in COVID-19 during the pandemic, considering the susceptibility profiles and the risk factors related to the species detected in a positive yeast culture. METHODS: From different samples of 33 patients with comorbidities, 42 clinical isolates were identified by VITEKâ MS Plus. Antifungal susceptibility testing was performed using VITEKâ 2 Compact with the AST-YS08 card. RESULTS: The most frequently identified species were C. albicans and C. glabrata, which were also the most common co-infections, Saprochaete capitata, an uncommon yeast was isolated in one patient. 85% of the co-infections were COVID positive and 100% of patients with a co-infection required mechanical ventilation (MV) which has been described as one of the major predisposing factors to candidiasis. Candida species vary in their response to treatment. In this study, 44% of isolates identified as C. glabrata were fluconazole-resistant, which were also immediately susceptible to caspofungin; this profile limits therapeutic options and emphasizes the importance of evaluating the susceptibility profile. CONCLUSIONS: This work highlights the increase in isolation of different Candida species during COVID-19 and the importance of establishing criteria to declare Candida colonization or infection and the correct etiological identification to establish an agent-based antifungal treatment, to reduce the spreading risk of Candida spp. in the hospital environment, mortality, time, and cost of hospitalization.
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Introduction: Tuberculosis (TB) is a bacterial infection caused by Mycobacterium tuberculosis (M.tb). B cells are the central mediator of the humoral response; they are responsible for producing antibodies in addition to mediating other functions. The role of the cellular response during the TB spectrum by B cells is still controversial. Methods: In this study, we evaluated the distribution of the circulating B cell subsets in patients with active and latent TB (ATB and LTB, respectively) and how they respond to stimuli of protein or lipid from M.tb. Results: Here, we show that ATB patients show an immune fingerprinting. However, patients with drug-sensitive- (DS-TB) or drug-resistant- (DR-TB) TB have altered frequencies of circulating B cells. DS-TB and DR-TB display a unique profile characterized by high systemic levels of IFN-γ, IL-10, IgG, IgG/IgM ratio, and total B cells. Moreover, B cells from DR-TB are less efficient in producing IL-10, and both DS-TB and DR-TB produce less IFN-γ in response to M.tb antigens. Conclusion: These results provide new insights into the population dynamics of the cellular immune response by B cells against M.tb and suggest a fingerprinting to characterize the B-cell response on DR-TB.
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Tuberculosis Latente , Mycobacterium tuberculosis , Tuberculosis , Humanos , Interleucina-10 , Interferón gamma/metabolismo , Inmunoglobulina GRESUMEN
Dysbiosis plays an important role in the development of bacterial infections in the gastric mucosa, particularly Helicobacter pylori. The international guidelines for the treatment of H. pylori infections suggest standard triple therapy (STT). Nevertheless, because of the increasing resistance rates to clarithromycin, metronidazole has been widely considered in several countries. Unfortunately, the non-justified administration of antibiotics induces dysbiosis in the target organ. We characterized the gastric microbiota of patients diagnosed with follicular gastropathy and pangastropathy attributed to H. pylori infection, before and after the administration of STT with metronidazole. Dominant relative abundances of Cutibacterium were observed in pre-treatment patients, whereas H. pylori was observed at <11%, suggesting the multifactor property of the disease. The correlation of Cutibacterium acnes and H. pylori with gastric infectious diseases was also evaluated using quantitative real-time polymerase chain reaction. The dominance of C. acnes over H. pylori was observed in gastritis, gastropathies, and non-significant histological alterations. None of the microorganisms were detected in the intestinal metaplasia. Post-treatment alterations revealed an increase in the relative abundances of Staphylococcus, Pseudomonas, and Klebsiella. Non-H. pylori gastrointestinal bacteria can be associated with the initiation and development of gastric diseases, such as pathobiont C. acnes.
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Currently, genome editing technologies, such as clustered regularly interspaced short palindromic repeats (CRISPR/Cas9), are predominantly used to model genetic diseases. This genome editing system can correct point or frameshift mutations in risk genes. Here, we analyze and discuss the advantages of genome editing, its current applications, and the feasibility of the CRISPR/Cas9 system in research on psychiatric disorders. These disorders produce cognitive and behavioral alterations and their etiology is associated with polygenetic and environmental factors. CRISPR/Cas9 may reveal the biological mechanisms of psychiatric disorders at a basic research level, translating a suitable clinical approach for use in the diagnosis and treatment of psychiatric disorders. Genetic diagnosis and treatment for these disorders have not yet been fully established in psychiatry due to the limited understanding of their heterogeneity and polygenicity. We discuss the challenges and ethical issues in using CRISPR/Cas9 as a tool for diagnosis or gene therapy.
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The use of sulfidogenic bioreactors is a biotechnology trend to recover valuable metals such as copper and zinc as sulfide biominerals from mine-impacted waters. In the present work, ZnS nanoparticles were produced using "green" H2S gas generated by a sulfidogenic bioreactor. ZnS nanoparticles were physico-chemically characterized by UV-vis and fluorescence spectroscopy, TEM, XRD and XPS. The experimental results showed spherical-like shape nanoparticles with principal zinc-blende crystalline structure, a semiconductor character with an optical band gap around 3.73 eV, and fluorescence emission in the UV-visible range. In addition, the photocatalytic activity on the degradation of organic dyes in water, as well as bactericidal properties against several bacterial strains, were studied. ZnS nanoparticles were able to degrade methylene blue and rhodamine in water under UV radiation, and also showed high antibacterial activity against different bacterial strains including Escherichia coli and Staphylococcus aureus. The results open the way to obtain valorous ZnS nanoparticles from the use of dissimilatory reduction of sulfate using a sulfidogenic bioreactor.
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Abstract Rhodococcus is a pathogen that is known to cause infections in animals and humans, mainly in cases of immunocompromised patients. A case of a pediatric cancer patient suffering from a bloodstream infection caused by Rhodococcus corynebacterioides was described in this work. Gram positive rods were isolated from blood cultures. The target bacterium was identified using a combination of biochemical tests, the MALDI-TOF mass spectrometry technique, and the analysis of the 16S rRNA sequence. Moreover, an antimicrobial susceptibility test was performed using the E-test. The isolated bacterium was identified as R. corynebacterioides. The 3-year-old patient was successfully treated with vancomycin and meropenem. This is the first published report of R. corynebacterioides in a pediatric patient diagnosed with retinoblastoma that developed a bloodstream infection. R. corynebacterioides should be considered among the opportunistic infectious agents affecting pediatric cancer patients.
Resumen Rhodococcus es un patógeno conocido por causar infecciones en animales y humanos, principalmente en pacientes inmunocomprometidos. En este trabajo se describe el caso de un paciente pediátrico con cáncer que presentó una infección del torrente sanguíneo causada por Rhodococcus corynebacterioides. A partir de hemocultivos, se aislaron bacilos gram positivos. La bacteria diana fue identificada usando una combinación de pruebas bioquímicas, por espectrometría de masas MALDI-TOF y por el análisis de la secuencia del gen 16S ARNr. Además, se realizó una prueba de sensibilidad a los antimicrobianos utilizando E-test. La cepa bacteriana se identificó como R. corynebacterioides. El paciente, de 3 años, fue tratado con vancomicina y meropenem, exitosamente. Este es el primer reporte de R. corynebacterioides como agente causal de una infección del torrente sanguíneo en un paciente pediátrico con retinoblastoma. R. corynebacterioides debe considerarse entre los agentes infecciosos oportunistas que afectan a los pacientes pediátricos con cáncer.
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Currently, genome editing technologies, such as clustered regularly interspaced short palindromic repeats (CRISPR/Cas9), are predominantly used to model genetic diseases. This genome editing system can correct point or frameshift mutations in risk genes. Here, we analyze and discuss the advantages of genome editing, its current applications, and the feasibility of the CRISPR/Cas9 system in research on psychiatric disorders. These disorders produce cognitive and behavioral alterations and their etiology is associated with polygenetic and environmental factors. CRISPR/Cas9 may reveal the biological mechanisms of psychiatric disorders at a basic research level, translating a suitable clinical approach for use in the diagnosis and treatment of psychiatric disorders. Genetic diagnosis and treatment for these disorders have not yet been fully established in psychiatry due to the limited understanding of their heterogeneity and polygenicity. We discuss the challenges and ethical issues in using CRISPR/Cas9 as a tool for diagnosis or gene therapy.
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Sistemas CRISPR-Cas , Edición Génica , Humanos , Sistemas CRISPR-Cas/genética , Terapia GenéticaRESUMEN
Rhodococcus is a pathogen that is known to cause infections in animals and humans, mainly in cases of immunocompromised patients. A case of a pediatric cancer patient suffering from a bloodstream infection caused by Rhodococcus corynebacterioides was described in this work. Gram positive rods were isolated from blood cultures. The target bacterium was identified using a combination of biochemical tests, the MALDI-TOF mass spectrometry technique, and the analysis of the 16S rRNA sequence. Moreover, an antimicrobial susceptibility test was performed using the E-test. The isolated bacterium was identified as R. corynebacterioides. The 3-year-old patient was successfully treated with vancomycin and meropenem. This is the first published report of R. corynebacterioides in a pediatric patient diagnosed with retinoblastoma that developed a bloodstream infection. R. corynebacterioides should be considered among the opportunistic infectious agents affecting pediatric cancer patients.
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Bacteriemia , Neoplasias de la Retina , Retinoblastoma , Rhodococcus , Sepsis , Animales , Humanos , Niño , Preescolar , Retinoblastoma/tratamiento farmacológico , ARN Ribosómico 16S/genética , Sepsis/diagnóstico , Sepsis/tratamiento farmacológico , Neoplasias de la Retina/complicaciones , Neoplasias de la Retina/tratamiento farmacológico , Bacteriemia/diagnóstico , Bacteriemia/tratamiento farmacológico , Bacteriemia/microbiología , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción , Antibacterianos/uso terapéuticoRESUMEN
The major histocompatibility complex (MHC) enables vertebrates to cope with pathogens and maintain healthy populations, thus making it a unique set of loci for addressing ecology and evolutionary biology questions. The aim of our study was to examine the variability of Heermann's Gull MHC class II (MHCIIB) and compare these loci with other Charadriiformes. Fifty-nine MHCIIB haplotypes were recovered from sixty-eight Heermann's Gulls by cloning, of them, twelve were identified as putative true alleles, forty-five as unique alleles, and two as pseudogenes. Intra and interspecific relationships indicated at least two loci in Heermann's Gull MHCIIB and trans-species polymorphism among Charadriiformes (coinciding with the documented evidence of two ancient avian MHCIIB lineages, except in the Charadriidae family). Additionally, sites under diversifying selection revealed a better match with peptide-binding sites inferred in birds than those described in humans. Despite the negative anthropogenic activity reported on Isla Rasa, Heermann's Gull showed MHCIIB variability consistent with population expansion, possibly due to a sudden growth following conservation efforts. Duplication must play an essential role in shaping Charadriiformes MHCIIB variability, buffering selective pressures through balancing selection. These findings suggest that MHC copy number and protected islands can contribute to seabird conservation.
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Charadriiformes , Animales , Aves/genética , Charadriiformes/genética , Genes MHC Clase II/genética , Antígenos de Histocompatibilidad Clase II/genética , Humanos , Filogenia , Selección GenéticaRESUMEN
BACKGROUND: Aging is an independent risk factor for deterioration in functional capacity. Some studies have reported that physical activity (PA) improves functional capacity and physical performance among older adults (OA). Thus the objective of the present study was to assess the longitudinal association between PA and functional and physical performance in non-institutionalized OA. METHODS: A longitudinal analysis using data from the Frailty, Dynapenia and Sarcopenia in Mexican adults (FRADYSMEX, by its Spanish acronym) cohort study was conducted. PA was assessed through the Community Healthy Activities Model Program for Seniors (CHAMPS) instrument. Functionality was measured with the Barthel index and the Lawton and Brody scale, while physical performance was measured with the Short Physical Performance Battery (SPPB). To evaluate the association between the level of PA and physical and functional performance as a continuous variable, a linear regression of mixed effects was performed. To assess PA and dependence in basic activities of the daily life (BADL), instrumental activities of the daily life (IADL), and low physical performance (PP), generalized estimation equation models [to compute odds ratios (OR) and 95% confidence intervals (95%CI)] were computed. RESULTS: Older people who performed moderate to vigorous-intensity PA had a lower risk of dependence in IADL (OR = 0.17; 95%CI: 0.10, 0.80) and lower risk of low PP (OR = 0.18; 95%CI: 0.11, 0.58) compared to those in lower categories of PA. CONCLUSIONS: Older adults living in the community who perform PA of moderate to vigorous intensity have a lower risk of dependence in BADL and IADL and have a lower risk of low PP.
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Fragilidad , Sarcopenia , Anciano , Estudios de Cohortes , Ejercicio Físico , Humanos , Rendimiento Físico FuncionalRESUMEN
Peristomal skin problems are common in ostomy patients and are connected to decreased quality of life and patient independence, as well as increased treatment costs. This study analysed the factors related to peristomal skin changes in order to better define the clinical profile of patients with optimal peristomal skin status. Secondary analysis of data from a nationwide, cross-sectional, retrospective, multicentre study performed in Spain (Uses and Attitudes in Ostomy) (Bueno Cruz et al, 2021) evaluated clinical data, including demographics, preoperative stoma site marking, type of ostomy, device used, frequency of leakage and scores from the Ostomy Skin Tool (OST) and quality of life (QoL) questionnaires. Risk factors for peristomal skin changes were analysed using multivariate analysis, and a predictive nomogram to anticipate optimal peristomal skin status (defined here as discolouration (D), erosion (E), and tissue overgrowth (T) (DET) score of 0) was developed. Some 871 patients with an ostomy using different commercial devices in Spain were evaluated. Multivariate analysis to predict optimal peristomal skin status revealed leakage frequency, patient age, type of ostomy, preoperative siting and type of baseplate used were independent predictors of peristomal skin status. Optimal peristomal skin care should be a treatment goal for nurse specialists in stomal therapy, and its individual influencing variables should be taken into account by nurses specialising in ostomy care.
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Estomía , Estomas Quirúrgicos , Estudios Transversales , Humanos , Calidad de Vida , Estudios Retrospectivos , Cuidados de la Piel , Estomas Quirúrgicos/efectos adversosRESUMEN
Extracellular vesicles (EVs) are evaginations of the cytoplasmic membrane, containing nucleic acids, proteins, lipids, enzymes, and toxins. EVs participate in various bacterial physiological processes. Staphylococcus epidermidis interacts and communicates with the host skin. S. epidermidis' EVs may have an essential role in this communication mechanism, modulating the immunological environment. This work aimed to evaluate if S. epidermidis' EVs can modulate cytokine production by keratinocytes in vitro and in vivo using the imiquimod-induced psoriasis murine model. S. epidermidis' EVs were obtained from a commensal strain (ATC12228EVs) and a clinical isolated strain (983EVs). EVs from both origins induced IL-6 expression in HaCaT keratinocyte cultures; nevertheless, 983EVs promoted a higher expression of the pro-inflammatory cytokines VEGF-A, LL37, IL-8, and IL-17F than ATCC12228EVs. Moreover, in vivo imiquimod-induced psoriatic skin treated with ATCC12228EVs reduced the characteristic psoriatic skin features, such as acanthosis and cellular infiltrate, as well as VEGF-A, IL-6, KC, IL-23, IL-17F, IL-36γ, and IL-36R expression in a more efficient manner than 983EVs; however, in contrast, Foxp3 expression did not significantly change, and IL-36 receptor antagonist (IL-36Ra) was found to be increased. Our findings showed a distinctive immunological profile induction that is dependent on the clinical or commensal EV origin in a mice model of skin-like psoriasis. Characteristically, proteomics analysis showed differences in the EVs protein content, dependent on origin of the isolated EVs. Specifically, in ATCC12228EVs, we found the proteins glutamate dehydrogenase, ornithine carbamoyltransferase, arginine deiminase, carbamate kinase, catalase, superoxide dismutase, phenol-soluble ß1/ß2 modulin, and polyglycerol phosphate α-glucosyltransferase, which could be involved in the reduction of lesions in the murine imiquimod-induced psoriasis skin. Our results show that the commensal ATCC12228EVs have a greater protective/attenuating effect on the murine imiquimod-induced psoriasis by inducing IL-36Ra expression in comparison with EVs from a clinical isolate of S. epidermidis.
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Vesículas Extracelulares/metabolismo , Psoriasis/terapia , Staphylococcus epidermidis/metabolismo , Animales , Antígenos Ly/metabolismo , Línea Celular , Modelos Animales de Enfermedad , Vesículas Extracelulares/química , Vesículas Extracelulares/trasplante , Humanos , Imiquimod/toxicidad , Interleucina-1/antagonistas & inhibidores , Interleucina-1/genética , Interleucina-1/metabolismo , Interleucina-17/genética , Interleucina-17/metabolismo , Interleucina-6/genética , Interleucina-6/metabolismo , Ratones , Infiltración Neutrófila , Psoriasis/inducido químicamente , Psoriasis/patología , Piel/metabolismo , Piel/patología , Factor A de Crecimiento Endotelial Vascular/genética , Factor A de Crecimiento Endotelial Vascular/metabolismoRESUMEN
Microbiomes are defined as complex microbial communities, which are mainly composed of bacteria, fungi, and viruses residing in diverse regions of the human body. The human stomach consists of a unique and heterogeneous habitat of microbial communities owing to its anatomical and functional characteristics, that allow the optimal growth of characteristic bacteria in this environment. Gastric dysbiosis, which is defined as compositional and functional alterations of the gastric microbiota, can be induced by multiple environmental factors, such as age, diet, multiple antibiotic therapies, proton pump inhibitor abuse, H. pylori status, among others. Although H. pylori colonization has been reported across the world, chronic H. pylori infection may lead to serious consequences; therefore, the infection must be treated. Multiple antibiotic therapy improvements are not always successful because of the lack of adherence to the prescribed antibiotic treatment. However, the abuse of eradication treatments can generate gastric dysbiotic states. Dysbiosis of the gastric microenvironment induces microbial resilience, due to the loss of relevant commensal bacteria and simultaneous colonization by other pathobiont bacteria, which can generate metabolic and physiological changes or even initiate and develop other gastric disorders by non-H. pylori bacteria. This systematic review opens a discussion on the effects of multiple environmental factors on gastric microbial communities.
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Outer membrane vesicles (OMVs) from Gram-negative bacteria were first described more than 50 years ago. However, the molecular mechanisms involved in biogenesis began to be studied only in the last few decades. Presently, the biogenesis and molecular mechanisms for their release are not completely known. This review covers the most recent information on cellular components involved in OMV biogenesis, such as lipoproteins and outer membrane proteins, lipopolysaccharide, phospholipids, quorum-sensing molecules, and flagella.
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Gram-negative bacteria release nanovesicles, called outer membrane vesicles (OMVs), from their outer membrane. Proteomics has been used to determine their composition. OMVs contain proteins able to elicit an immune response, so they have been proposed as a model to develop acellular vaccines. In this study, OMVs of Brucella suis, B. ovis, B. canis, and B. neotomae were purified and analyzed by SDS-PAGE, transmission electron microscopy and liquid chromatography coupled to mass spectrometry to determine the pan-proteome of these vesicles. In addition, antigenic proteins were detected by western blot with anti-Brucella sera. The in silico analysis of the pan-proteome revealed many homologous proteins, such as Omp16, Omp25, Omp31, SodC, Omp2a, and BhuA. Proteins contained in the vesicles from different Brucella species were detected by anti-Brucella sera. The occurrence of previously described immunogenic proteins derived from OMVs supports the use of these vesicles as candidates to be evaluated as an acellular brucellosis vaccine.
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Antígenos Bacterianos , Proteínas Bacterianas , Brucella , Proteoma , Animales , Antígenos Bacterianos/genética , Antígenos Bacterianos/metabolismo , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Brucella/genética , Brucella/metabolismo , Brucella canis , Brucella ovis , Brucella suis , Electroforesis en Gel de Poliacrilamida , Proteoma/genética , ProteómicaRESUMEN
Similar to what has been described in other Gram-negative bacteria, Brucella melitensis releases outer membrane vesicles (OMVs). OMVs from B. melitensis 16M and the rough-mutant B. melitensis VTRM1 were able to induce a protective immune response against virulent B. melitensis in mice models. The presence of some proteins which had previously been reported to induce protection against Brucella were found in the proteome of OMVs from B. melitensis 16M. However, the proteome of OMVs from B. melitensis VTRM1 had not previously been determined. In order to be better understand the role of OMVs in host-cell interactions, the aim of this work was to compare the proteomes of OMVs from B. melitensis 16M and the derived rough-mutant B. melitensis VTRM1, as well as to characterize the immune response induced by vesicles on host cells. Additionally, the effect of SDS and proteinase K on the stability of OMVs was analyzed. OMVs from B. melitensis 16M (smooth strain) and the B. melitensis VTRM1 rough mutant (lacking the O-polysaccharide side chain) were analyzed through liquid chromatography-mass spectrometry (LC-MS/MS). OMVs were treated with proteinase K, sodium deoxycholate, and SDS, and then their protein profile was determined using SDS-PAGE. Furthermore, PBMCs were treated with OMVs in order to measure their effect on cytoskeleton, surface molecules, apoptosis, DNA damage, proliferation, and cytokine-induction. A total of 131 proteins were identified in OMVs from B. melitensis16M, and 43 in OMVs from B. melitensis VTRM1. Proteome comparison showed that 22 orthologous proteins were common in vesicles from both strains, and their core proteome contained Omp31, Omp25, GroL, and Omp16. After a subsequent detergent and enzyme treatment, OMVs from B. melitensis VTRM1 exhibited higher sensitive compared to OMVs from the B. melitensis 16M strain. Neither OMVs induced IL-17, proliferation, apoptosis or DNA damage. Nonetheless, OMVs from the smooth and rough strains induced overproduction of TNFα and IL-6, as well as actin and tubulin rearrangements in the cytoskeleton. Moreover, OMVs from both strains inhibited PD-L1 expression in T-cells. These data revealed significant differences in OMVs derived from the rough and smooth Brucella strains, among which, the presence or absence of complete LPS appeared to be crucial to protect proteins contained within vesicles and to drive the immune response.
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Combining ion-imprinting technology with pH-dependent adsorptive features of acid- or salt-activated zeolites brings up the opportunity to develop composite polymer materials with 'desired' sorption properties and performances. In this respect, we present here Co2+-imprinted composite cryo-beads with switching on/off selectivity towards the template ions, engineered by selecting the appropriate zeolite-treatment conditions and/or controlling the initial sorption pH values. Co2+ chelating efficiency of all cryo-beads was investigated either at pHâ¯4 or 6 depending on zeolite conditioning strategy. The maximum sorption capacity values of ion-imprinted cryo-beads were from about 5 up to 7 times higher compared with those of non-imprinted ones. Under competitive conditions (Cu2+, Ni2+, Fe2+ and Cd2+ ions), the change of pH value from 4 to 6 resulted in a remarkable quenching of Co2+ selectivity generated by the zeolite shift from the H+-form to the Na+-form. The presence of zeolites within cryogel matrix generated composites with outstanding elasticity that allows the instant recovery of gels after full compression. These results indicate that the cryogel-type composites can be successfully re-used in separation processes for several times without losing their features.
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Quelantes/química , Quitosano/química , Criogeles/química , Metales Pesados/química , Zeolitas/química , Concentración de Iones de Hidrógeno , CinéticaRESUMEN
As dendritic cells (DCs) are among the first cells to encounter antigens, these cells trigger both innate and T cell responses, and are the most potent antigen-presenting cells. Brucella spp., which is an intracellular facultative and stealthy pathogen, is able to evade the bactericidal activities of professional phagocytes. Several studies have demonstrated that Brucella can survive and replicate intracellularly, thereby provoking impaired maturation of DCs. Therefore, the interaction between DCs and Brucella becomes an interesting model to study the immune response. In this review, we first will describe the most common techniques for DCs differentiation in vitro as well as general features of brucellosis. Then, the interaction of DCs and Brucella, including pathogen recognition, molecular mechanisms of bacterial pathogenesis, and intracellular trafficking of Brucella to subvert innate response, will be reviewed. Finally, we will debate diversity in immunological DC response and the controversial role of DC activation against Brucella infection.