RESUMEN
Celiac disease (CD) is an immune-driven disease characterized by tissue damage in the small intestine of genetically-susceptible individuals. We evaluated here a crucial immune regulatory pathway involving TYRO3, AXL, and MERTK (TAM) receptors and their ligands PROS1 and GAS6 in duodenal biopsies of controls and CD patients. We found increased GAS6 expression associated with downregulation of PROS1 and variable TAM receptors levels in duodenum tissue of CD patients. Interestingly, CD3+ lymphocytes, CD68+, CD11c+ myeloid and epithelial cells, showed differential expressions of TAM components comparing CD vs controls. Principal component analysis revealed a clear segregation of two groups of CD patients based on TAM components and IFN signaling. In vitro validation demonstrated that monocytes, T lymphocytes and epithelial cells upregulated TAM components in response to IFN stimulation. Our findings highlight a dysregulated TAM axis in CD related to IFN signaling and contribute to a deeper understanding of the pathophysiology of CD.
Asunto(s)
Tirosina Quinasa del Receptor Axl , Enfermedad Celíaca , Duodeno , Péptidos y Proteínas de Señalización Intercelular , Mucosa Intestinal , Proteína S , Proteínas Tirosina Quinasas Receptoras , Tirosina Quinasa c-Mer , Femenino , Humanos , Masculino , Tirosina Quinasa c-Mer/genética , Tirosina Quinasa c-Mer/metabolismo , Enfermedad Celíaca/inmunología , Enfermedad Celíaca/metabolismo , Enfermedad Celíaca/genética , Duodeno/metabolismo , Duodeno/inmunología , Duodeno/patología , Péptidos y Proteínas de Señalización Intercelular/genética , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Interferones/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/inmunología , Proteína S/metabolismo , Proteína S/genética , Proteínas Proto-Oncogénicas/metabolismo , Proteínas Proto-Oncogénicas/genética , Proteínas Tirosina Quinasas Receptoras/metabolismo , Proteínas Tirosina Quinasas Receptoras/genética , Proteínas Tirosina Quinasas Receptoras/inmunología , Transducción de Señal , Linfocitos T/inmunología , Linfocitos T/metabolismoRESUMEN
Usually, the massive elimination of cells under steady-state conditions occurs by apoptosis, which is also acknowledged to explain the loss of enterocytes in the small intestine of celiac disease (CD) patients. However, little is known about the role of proinflammatory cell death pathways in CD. Here, we have used confocal microscopy, western blot, and RT-qPCR analysis to assess the presence of regulated cell death pathways in the duodenum of CD patients. We found an increased number of dead (TUNEL+) cells in the lamina propria of small intestine of CD patients, most of them are plasma cells (CD138+). Many dying cells expressed FAS and were in close contact with CD3+ T cells. Caspase-8 and caspase-3 expression was increased in CD, confirming the activation of apoptosis. In parallel, caspase-1, IL-1ß, and GSDMD were increased in CD samples indicating the presence of inflammasome-dependent pyroptosis. Necroptosis was also present, as shown by the increase of RIPK3 and phosphorylate MLKL. Analysis of published databases confirmed that CD has an increased expression of regulated cell death -related genes. Together, these results reveal that CD is characterized by cell death of different kinds. In particular, the presence of proinflammatory cell death pathways may contribute to mucosal damage.
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Enfermedad Celíaca , Piroptosis , Humanos , Piroptosis/genética , Necroptosis/genética , Apoptosis/genética , Muerte CelularRESUMEN
Research on the use of biomass resources for the generation of energy and chemical compounds is of great interest worldwide. The development and growth of the biodiesel industry has led to a parallel market for the supply of glycerol, its main by-product. Its wide availability and relatively low cost as a raw material make glycerol a basic component for obtaining various chemical products and allows for the development of a biorefinery around biodiesel plants, through the technological integration of different production processes. This work proposes a review of one of the reactions of interest in the biorefinery environment: the hydrogenolysis of glycerol to 1,2-propylene glycol. The article reviews more than 300 references, covering literature from about 20 years, focusing on the heterogeneous catalysts used for the production of glycol. In this sense, from about 175 catalysts, between bulk and supported ones, were revised and discussed critically, based on noble metals, such as Ru, Pt, Pd, and non-noble metals as Cu, Ni, Co, both in liquid (2-10 MPa, 120-260 °C) and vapor phase (0.1 MPa, 200-300 °C). Then, the effect of the main operational and decision variables, such as temperature, pressure, catalyst/glycerol mass ratio, space velocity, and H2 flow, are discussed, depending on the reactors employed. Finally, the formulation of several kinetic models and stability studies are presented, discussing the main deactivation mechanisms of the catalytic systems such as coking, leaching, and sintering, and the presence of impurities in the glycerol feed. It is expected that this work will serve as a tool for the development of more efficient catalytic materials and processes towards the future projection of glycerol biorefineries.
RESUMEN
The intestinal mucosa is covered by a layer of epithelial cells that is constantly challenged by commensal, opportunistic, and pathogenic microorganisms, their components, and harmful compounds. Any inflammatory response to these materials must be tightly controlled to limit tissue damage and restore the integrity of the mucosal barrier. We have shown previously that production of IL-1ß via activation of the inflammasome can lead to mucosal damage in the small intestinal pathology that occurs after intragastric administration of a gluten derived peptide, p31-43. Here we show that specific inhibition of caspase-1 or NLRP3 abolishes the damage induced by p31-43, and that antibody-mediated blocking of IL-1ß inhibits the both the histological changes and the induction of apoptosis and caspase-3 activation driven by p31-43. Understanding the role of IL-1ß in sterile inflammation may help to understand chronic inflammatory pathological processes, and design new intervention strategies.
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Inflamasomas , Proteína con Dominio Pirina 3 de la Familia NLR , Humanos , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Inflamasomas/metabolismo , Interleucina-1beta/metabolismo , Caspasa 1/metabolismo , Inflamación/patología , Intestino Delgado/patología , ApoptosisRESUMEN
The small intestine has a high rate of cell turnover under homeostatic conditions, and this increases further in response to infection or damage. Epithelial cells mostly die by apoptosis, but recent studies indicate that this may also involve pro-inflammatory pathways of programmed cell death, such as pyroptosis and necroptosis. Celiac disease (CD), the most prevalent immune-based enteropathy, is caused by loss of oral tolerance to peptides derived from wheat, rye, and barley in genetically predisposed individuals. Although cytotoxic cells and gluten-specific CD4+ Th1 cells are the central players in the pathology, inflammatory pathways induced by cell death may participate in driving and sustaining the disease through the release of alarmins. In this review, we summarize the recent literature addressing the role of programmed cell death pathways in the small intestine, describing how these mechanisms may contribute to CD and discussing their potential implications.
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Apoptosis , Enfermedad Celíaca/patología , Intestino Delgado/patología , Animales , Enfermedad Celíaca/etiología , HumanosRESUMEN
Intestinal epithelial cells have a rapid turnover, being rapidly renewed by newly differentiated enterocytes, balanced by massive and constant removal of damaged cells by programmed cell death (PCD). The main forms of PCD are apoptosis, pyroptosis, and necroptosis, with apoptosis being a noninflammatory process, whereas the others drive innate immune responses. Although apoptosis is thought to be the principal means of cell death in the healthy intestine, which mechanisms are responsible for PCD during inflammation are not fully understood. To address this question, we used an in vivo model of enteropathy in wild-type mice induced by a single intragastric administration of the p31-43 gliadin peptide, which is known to elicit transient MyD88, NLRP3, and caspase-1-dependent mucosal damage and inflammation in the small intestine. Here, we found increased numbers of TUNEL+ cells in the mucosa as early as 2 h after p31-43 administration. Western blot and immunofluorescence analysis showed the presence of caspase-3-mediated apoptosis in the epithelium and lamina propria. In addition, the presence of mature forms of caspase-1, IL-1ß, and gasdermin D showed activation of pyroptosis and inhibition of caspase-1 led to decreased enterocyte death in p31-43-treated mice. There was also up-regulation of RIPK3 in crypt epithelium, suggesting that necroptosis was also occurring. Taken together, these results indicate that the inflammatory response induced by p31-43 can drive multiple PCD pathways in the small intestine.
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Inflamación/inmunología , Enfermedades Intestinales/inmunología , Intestino Delgado/inmunología , Muerte Celular Regulada/inmunología , Animales , Inflamación/metabolismo , Inflamación/patología , Enfermedades Intestinales/metabolismo , Enfermedades Intestinales/patología , Intestino Delgado/metabolismo , Intestino Delgado/patología , Masculino , Ratones , Ratones Endogámicos C57BLRESUMEN
Initially described as Th2 promoter cytokine, more recently, IL-33 has been recognized as an alarmin, mainly in epithelial and endothelial cells. While localized in the nucleus acting as a gene regulator, it can be also released after injury, stress or inflammatory cell death. As proinflammatory signal, IL-33 binds to the surface receptor ST2, which enhances mast cell, Th2, regulatory T cell, and innate lymphoid cell type 2 functions. Besides these Th2 roles, free IL-33 can activate CD8+ T cells during ongoing Th1 immune responses to potentiate its cytotoxic function. Celiac Disease (CD) is a chronic inflammatory disorder characterized by a predominant Th1 response leading to multiple pathways of mucosal damage in the proximal small intestine. By immunofluorescence and western blot analysis of duodenal tissues, we found an increased expression of IL-33 in duodenal mucosa of active CD (ACD) patients. Particularly, locally digested IL-33 releases active 18/21kDa fragments which can contribute to expand the proinflammatory signal. Endothelial (CD31+) and mesenchymal, myofibroblast and pericyte cells from microvascular structures in villi and crypts, showed IL-33 nuclear location; while B cells (CD20+) showed a strong cytoplasmic staining. Both ST2 forms, ST2L and sST2, were also upregulated in duodenal mucosa of CD patients. This was accompanied by increased number of CD8+ST2+ T cells and the expression of T-bet in some ST2+ intraepithelial lymphocytes and lamina propria cells. IL-33 and sST2 mRNA levels correlated with IRF1, an IFN induced factor relevant in responses to viral infections and interferon mediated proinflammatory responses highly represented in duodenal tissues in ACD. These findings highlight the potential contribution of IL-33 and its fragments to exacerbate the proinflammatory circuit and potentiate the cytotoxic activity of CD8+ T cells in CD pathology.
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Alarminas/inmunología , Enfermedad Celíaca/inmunología , Inflamación/inmunología , Interleucina-33/inmunología , Intestino Delgado/inmunología , Animales , Linfocitos B/inmunología , Linfocitos T CD8-positivos/inmunología , Línea Celular Tumoral , Citocinas/inmunología , Células HT29 , Humanos , Proteína 1 Similar al Receptor de Interleucina-1/inmunología , Mucosa Intestinal/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL , Linfocitos T Reguladores/inmunología , Células Th2/inmunologíaRESUMEN
El síndrome anti-GQ1b reúne el síndrome de Miller-Fisher y la encefalitis del tronco cerebral de Bickerstaff, entre otras entidades. Tienen etiopatogenia común, constituida por la presencia de anticuerpos anti-GQ1b que reaccionan contra los sitios GQ1b del sistema nervioso según sea su accesibilidad. La prevalencia anual del síndrome de Miller-Fisher es de 0,09 casos por 100 000 habitantes por año y no existen estudios epidemiológicos sobre la encefalitis del tronco cerebral de Bickerstaff, que sería menos frecuente. De evolución natural hacia la mejoría, se beneficia del tratamiento con gammaglobulina endovenosa.Se presenta a un paciente de 12 años con síndrome de Miller-FisherBickerstaff tras un episodio de diarrea aguda por Campylobacter jejuni en el que los anticuerpos anti-GQ1b resultaron positivos. Es nuestro objetivo comunicar sobre un síndrome de presentación poco habitual en pediatría a fin de advertir acerca de la necesidad de su sospecha precoz y solicitud de estudios de laboratorio específico
Miller-Fisher syndrome and Bickerstaff brainstem encephalitis, among others, constitute the anti-GQ1b syndrome, with a common immune pathophysiologic pathway characterized by the presence of anti-GQ1b antibodies, which react against the different nervous system GQ1b sites according to their different accessibility. The Miller-Fisher syndrome has a prevalence of 0.09 cases per 100 000 people-year but there are not epidemiological studies about Bickerstaff brainstem encephalitis, that it seems to be less frequent. In spite of having a good natural outcome, the immunoglobulin administration has been established as efficacious at improving it. A twelve-year-old boy suffering from Miller-Fisher-Bickerstaff syndrome after an acute Campylobacter jejuni diarrhea with positive titers of anti-GQ1b and anti-QGT1a antibodies is presented. We communicate a very uncommon pediatric disease with the aim of warning about the importance of its early suspicion and the need of specific laboratory determination
Asunto(s)
Humanos , Masculino , Niño , Síndrome de Miller Fisher , gammaglobulinas/uso terapéutico , Diarrea , Diplopía , Encefalitis , AnticuerposRESUMEN
Miller-Fisher syndrome and Bickerstaff brainstem encephalitis, among others, constitute the anti-GQ1b syndrome, with a common immune pathophysiologic pathway characterized by the presence of anti-GQ1b antibodies, which react against the different nervous system GQ1b sites according to their different accessibility. The Miller-Fisher syndrome has a prevalence of 0.09 cases per 100 000 people-year but there are not epidemiological studies about Bickerstaff brainstem encephalitis, that it seems to be less frequent. In spite of having a good natural outcome, the immunoglobulin administration has been established as efficacious at improving it. A twelveyear- old boy suffering from Miller-Fisher-Bickerstaff syndrome after an acute Campylobacter jejuni diarrhea with positive titers of anti-GQ1b and anti-QGT1a antibodies is presented. We communicate a very uncommon pediatric disease with the aim of warning about the importance of its early suspicion and the need of specific laboratory determinations.
El síndrome anti-GQ1b reúne el síndrome de Miller-Fisher y la encefalitis del tronco cerebral de Bickerstaff, entre otras entidades. Tienen etiopatogenia común, constituida por la presencia de anticuerpos anti-GQ1b que reaccionan contra los sitios GQ1b del sistema nervioso según sea su accesibilidad. La prevalencia anual del síndrome de Miller-Fisher es de 0,09 casos por 100 000 habitantes por año y no existen estudios epidemiológicos sobre la encefalitis del tronco cerebral de Bickerstaff, que sería menos frecuente. De evolución natural hacia la mejoría, se beneficia del tratamiento con gammaglobulina endovenosa. Se presenta a un paciente de 12 años con síndrome de Miller- FisherBickerstaff tras un episodio de diarrea aguda por Campylobacter jejuni en el que los anticuerpos anti-GQ1b resultaron positivos. Es nuestro objetivo comunicar sobre un síndrome de presentación poco habitual en pediatría a fin de advertir acerca de la necesidad de su sospecha precoz y solicitud de estudios de laboratorio específicos.
Asunto(s)
Autoanticuerpos/inmunología , Autoantígenos/inmunología , Encefalitis/diagnóstico , Gangliósidos/inmunología , Síndrome de Miller Fisher/diagnóstico , Autoanticuerpos/sangre , Autoantígenos/sangre , Biomarcadores/sangre , Niño , Encefalitis/sangre , Encefalitis/inmunología , Encefalitis/fisiopatología , Humanos , Masculino , Síndrome de Miller Fisher/sangre , Síndrome de Miller Fisher/inmunología , Síndrome de Miller Fisher/fisiopatología , SíndromeRESUMEN
In this study, it was evaluated and documented the potential uses of the residual fungal biomass from fermentation. The chemical composition of the biomass was determined by instrumental analysis techniques for its characterization and its possible application. It was found that this biomaterial is generally composed of sugars, proteins, and lipids, which provide it certain properties and applications that must be characterized morphologically, chemically, and mechanically. The residual fungal biomass could be used for two processes: the extraction of biopolymers, with several applications in the food industry, cosmetics, and pharmaceutical, among others; and the removal of contaminants by mechanisms of adsorption with biopolymers, known also as biosorption, in tertiary treatments of wastewater.
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Contaminantes Químicos del Agua , Adsorción , Biomasa , Hongos , Aguas ResidualesRESUMEN
Surface waters are an unappreciated reservoir of antimicrobial resistance (AMR). Poor sanitation brings different species of environmental bacteria into contact, facilitating horizontal gene transfer. To investigate the role of surface waters as potential reservoirs of AMR, we studied the point prevalence of fecal contamination, AMR genes, and Enterobacteriaceae in an urban lake and rural river system in Northeast Brazil in comparison with a lake and sewer system in Northeast Ohio in the United States. Surface water samples were examined for evidence of human fecal contamination using microbial source tracking and screened for plasmid-mediated fluoroquinolone resistance and carbapenemase genes. Enterobacteriaceae were detected using selective agar followed by antimicrobial susceptibility testing and detection of AMR genes by microarray, and classified by repetitive sequence-based polymerase chain reaction and multilocus sequence typing. Concentrations of human fecal bacteria in the Brazilian urban lake and sewage in Northeast Ohio were similarly high. Filtered water samples from the Brazilian urban lake, however, showed the presence of bla OXA-48, bla KPC, bla VIM-2, qnrS, and aac(6')-lb-cr, whereas only bla VIM-2 was identified in raw sewage from Northeast Ohio. From the Brazilian urban lake, 85% of the Enterobacteriaceae (n = 40) cultured were resistant to at least one clinically important antibiotic, including ST131 Escherichia coli harboring the extended-spectrum beta-lactamase CTX-M. Although two isolates demonstrated polymyxin resistance, mcr-1/2 was not detected. Our findings indicate that surface waters in an urban Brazilian site can serve as an environmental reservoir of AMR and that improving wastewater treatment and sanitation generally may ameliorate AMR dissemination.
Asunto(s)
Antibacterianos/farmacología , Enterobacteriaceae/efectos de los fármacos , Microbiología del Agua , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Brasil , Farmacorresistencia Bacteriana Múltiple , Enterobacteriaceae/genética , Regulación Bacteriana de la Expresión Génica , Humanos , Lagos , Saneamiento , Salud UrbanaRESUMEN
Celiac disease (CD) is a chronic enteropathy elicited by a Th1 response to gluten peptides in the small intestine of genetically susceptible individuals. However, it remains unclear what drives the induction of inflammatory responses of this kind against harmless antigens in food. In a recent work, we have shown that the p31-43 peptide (p31-43) from α-gliadin can induce an innate immune response in the intestine and that this may initiate pathological adaptive immunity. The receptors and mechanisms responsible for the induction of innate immunity by p31-43 are unknown and here we present evidence that this may reflect conformational changes in the peptide that allow it to activate the NLRP3 inflammasome. Administration of p31-43, but not scrambled or inverted peptides, to normal mice induced enteropathy in the proximal small intestine, associated with increased production of type I interferon and mature IL-1ß. P31-43 showed a sequence-specific spontaneous ability to form structured oligomers and aggregates in vitro and induced activation of the ASC speck complex. In parallel, the enteropathy induced by p31-43 in vivo did not occur in the absence of NLRP3 or caspase 1 and was inhibited by administration of the caspase 1 inhibitor Ac-YVAD-cmk. Collectively, these findings show that p31-43 gliadin has an intrinsic propensity to form oligomers which trigger the NLRP3 inflammasome and that this pathway is required for intestinal inflammation and pathology when p31-43 is administered orally to mice. This innate activation of the inflammasome may have important implications in the initial stages of CD pathogenesis.
Asunto(s)
Caspasa 1/metabolismo , Gliadina/metabolismo , Inflamasomas/metabolismo , Mucosa Intestinal/metabolismo , Mucosa Intestinal/patología , Proteína con Dominio Pirina 3 de la Familia NLR/metabolismo , Fragmentos de Péptidos/metabolismo , Multimerización de Proteína , Secuencia de Aminoácidos , Animales , Apoptosis , Enfermedad Celíaca/etiología , Enfermedad Celíaca/metabolismo , Modelos Animales de Enfermedad , Susceptibilidad a Enfermedades , Gliadina/química , Gliadina/ultraestructura , Mucosa Intestinal/ultraestructura , Intestino Delgado , Masculino , Ratones , Ratones Transgénicos , Modelos Moleculares , Proteína con Dominio Pirina 3 de la Familia NLR/genética , Fragmentos de Péptidos/química , Fragmentos de Péptidos/ultraestructura , Conformación Proteica , Relación Estructura-ActividadRESUMEN
The human pathogen Acinetobacter baumannii possesses high genetic plasticity and frequently acquires antimicrobial resistance genes. Here we investigated the role of natural transformation in these processes. Genomic DNA from different sources, including from carbapenem-resistant Klebsiella pneumoniae strains, was mixed with A. baumannii A118 cells. Selected transformants were analysed by whole-genome sequencing. In addition, bioinformatics analyses and in silico gene flow prediction were also performed to support the experimental results. Transformant strains included some that became resistant to carbapenems or changed their antimicrobial susceptibility profile. Foreign DNA acquisition was confirmed by whole-genome analysis. The acquired DNA most frequently identified corresponded to mobile genetic elements, antimicrobial resistance genes and operons involved in metabolism. Bioinformatics analyses and in silico gene flow prediction showed continued exchange of genetic material between A. baumannii and K. pneumoniae when they share the same habitat. Natural transformation plays an important role in the plasticity of A. baumannii and concomitantly in the emergence of multidrug-resistant strains.
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Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/genética , Antibacterianos/farmacología , Carbapenémicos/farmacología , ADN Bacteriano/metabolismo , Farmacorresistencia Bacteriana Múltiple/genética , Klebsiella pneumoniae/genética , Transformación Bacteriana/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , ADN Bacteriano/genética , Genoma Bacteriano/genética , Humanos , Secuencias Repetitivas Esparcidas/genética , Klebsiella pneumoniae/efectos de los fármacos , Pruebas de Sensibilidad Microbiana , Secuenciación Completa del GenomaRESUMEN
La Corea de Sydenham (CS), manifestación mayor, tardía, frecuentemente única de la Fiebre Reumática (FR) y marcador de carditis, continúa afectando a nuestra población pediátrica pese a contar con los medios suficientes para evitarla. Presentamos tres casos de CS como manifestación de FR, con la presencia de carditis, atendidos en una sala de internación de un hospital público pediátrico en el lapso de los años 2014-2018. Es nuestra intención advertir a la comunidad médica sobre la importancia del tratamiento oportuno y completo de las faringitis estreptocócicas (grupos A, C y G) a fin de evitar la FR
Sydenham Korea (CS), a major, late, frequently unique manifestation of Rheumatic Fever (FR) and a carditis marker, continues to affect our pediatric population despite having sufficient means to avoid it. We present three cases of CS as manifestation of RF, with the presence of carditis, treated in an internment room of a pediatric public hospital during the years 2014-2018. It is our intention to warn the medical community about the importance of the timely and complete treatment of strep throat (groups A, C and G) in order to avoid RF
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Humanos , Fiebre Reumática , Niño , Corea , PediatríaRESUMEN
La cianosis es la coloración azulada de la piel y las mucosas debida al aumento de la concentración de hemoglobina reducida en los capilares o a la presencia de metahemoglobina en concentraciones mayores de las normales. Es importante pensar en metahemoglobinemia como diagnóstico diferencial frente a un paciente con cianosis que no responde a la administración de oxígeno cuando no existen causas cardiorrespiratorias que la justifiquen, dado que requiere de otros métodos diagnósticos y de tratamiento específico. Se presenta el caso de un paciente adolescente de 14 años de edad con cianosis secundaria a metahemoglobinemia de probable etiología congénita. Se discuten las causas, forma de presentación, diagnóstico y tratamiento.
The bluish coloration of skin and mucous membranes, called as cyanosis, could be explained by high reduced hemoglobin in the capillaries, or the presence of elevated methemoglobin concentration. It is important to think of methemoglobinemia as a differential diagnosis in a cyanotic patient who does not respond to oxygen administration once cardiorespiratory causes are discarded; since it requires other diagnostic methods and specific treatment. We described a case of cyanosis in a fourteen-year-old adolescent with probable congenital methemoglobinemia. We discussed their probable causes, clinic presentation, diagnosis and treatment.
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Humanos , Masculino , Adolescente , Cianosis/etiología , Metahemoglobinemia/congénito , Cianosis/diagnóstico , Diagnóstico Diferencial , Metahemoglobinemia/complicaciones , Metahemoglobinemia/diagnósticoRESUMEN
OBJECTIVES: The aim of this study was to examine the population structure of representative carbapenem-resistant Enterobacter cloacae complex (CR-Ecl) isolates from eight different Colombian regions and to characterise their associated ß-lactamases. METHODS: A total of 28 CR-Ecl isolates collected in Colombia between 2009-2013 through the Colombian Nosocomial Network were included in this study. Antimicrobial susceptibility testing was performed by the broth microdilution method. Molecular detection of carbapenemase and extended-spectrum ß-lactamase (ESBL) genes and the presence of transposon Tn4401 was evaluated by PCR and DNA sequencing. Genetic relatedness was assessed by multilocus sequencing typing (MLST) and repetitive sequence-based PCR (rep-PCR). RESULTS: PCR and DNA sequencing revealed that 19/28 (68%) of the CR-Ecl isolates carried blaKPC-2. Analysis of the genetic environment found blaKPC-2 within transposon Tn4401b in 8/19 isolates (42%). Population genetic analysis using rep-PCR revealed four clonal groups. MLST showed a variety of sequence types (STs), among which ST510 was the most common (10/28 isolates; 36%). CONCLUSIONS: blaKPC-2 was discovered as the most common mechanism of carbapenem resistance in CR-Ecl and was disseminated among different STs. Although none of the previously reported major clonal complexes were identified, it appears that local strain lineages are associated with the spread of blaKPC within CR-Ecl in various regions of Colombia.
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Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Farmacorresistencia Bacteriana Múltiple , Enterobacter cloacae/efectos de los fármacos , Enterobacter cloacae/genética , beta-Lactamasas/genética , Antibacterianos/farmacología , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Carbapenémicos/farmacología , Colombia/epidemiología , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/microbiología , Humanos , Tipificación de Secuencias MultilocusRESUMEN
The global success of multidrug-resistant Acinetobacter baumannii has been associated with the dissemination of a high-risk clone designated clonal complex (CC) 92B (Bartual scheme)/CC2P (Pasteur scheme), which is the most frequent genetic lineage in European, Asian, and North American carbapenem-resistant Acinetobacter isolates. In these isolates, carbapenem resistance is mainly mediated by ß-lactamases encoded by blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, and/or blaOXA-58-like genes. In this study, we characterized the population genetics of 121 carbapenem-resistant A. baumannii complex isolates recovered from 14 hospitals in seven cities in Colombia (2008-2010). Multiplex PCR was used to detect blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, and blaOXA-58-like genes. Molecular typing was performed using pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing (MLST). PCR showed that 118 (97.5%) of the isolates were positive for both blaOXA-23-like and blaOXA-51-like genes, and three other isolates were only positive for blaOXA-51-like. PFGE identified 18 different pulsotypes, while MLST identified 11 different sequence types (STs), seven of which had not been previously described in Acinetobacter. None of the STs found in this study was associated with CC92B/CC2P. The most widespread STs in our isolates belonged to ST636 and their single-locus variants ST121/ST124/ST634 (CC636B) followed by STs belonging to CC110B. Our observations suggest a wide distribution of diverse A. baumannii complex clones containing blaOXA-23-like in Colombian hospitals (especially CC636B and CC110B) that differ from the high-risk clones commonly found in other regions of the world, indicating a distinct molecular epidemiology of carbapenem-resistant Acinetobacter spp. in Colombia.
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Infecciones por Acinetobacter/epidemiología , Acinetobacter baumannii/genética , Antibacterianos/farmacología , Carbapenémicos/farmacología , Regulación Bacteriana de la Expresión Génica , Resistencia betalactámica/genética , beta-Lactamasas/genética , Infecciones por Acinetobacter/tratamiento farmacológico , Infecciones por Acinetobacter/microbiología , Acinetobacter baumannii/clasificación , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/crecimiento & desarrollo , Células Clonales , Colombia/epidemiología , Electroforesis en Gel de Campo Pulsado , Variación Genética , Hospitales , Humanos , Pruebas de Sensibilidad Microbiana , Epidemiología Molecular , Tipificación de Secuencias Multilocus , Reacción en Cadena de la Polimerasa Multiplex , Serogrupo , beta-Lactamasas/clasificación , beta-Lactamasas/metabolismoRESUMEN
La enfermedad celíaca (EC) es una enfermedad autoinmune multisistémica que afecta principalmente al intestino delgado. Generalmente se presenta con diarrea, malabsorción y pérdida de peso. A menudo se asocia con trastornos endócrinos autoinmunes tales como: enfermedad de tiroides (tiroiditis de Hashimoto) y diabetes mellitus insulinodependiente (tipo 1), enfermedad de Addison autoinmune (insuficiencia suprarrenal) e insuficiencia ovárica. Dicha asociación estaría determinada genéticamente debido a la detección común del antígeno linfocítico humano. Se presenta caso clínico de una niña de 4 años que se interna por diarrea, edema y desnutrición, en la que se diagnostica EC y tiroiditis autoinmune
Celiac disease is a multysistemic autoimmune disorder that principally affects the first portion of the small bowel. Diarrhea, abdominal distention and failure to thrive are their most frequent complaints. It is frequently associated with endocrine autoimmune disorders such as: autoimmune thyroiditis (Hashimoto Disease), insulin dependent type I diabetes mellitus; Addison's disease and ovaric autoimmune disease, both of them, the latter, causing their respective insufficiencies. That association would be genetically determined since human lymphocytic antigen has been found in both. We present a case of a four-year-old girl who was admitted for diarrhea, edema and malnutrition, in which CD and autoimmune thyroiditis were diagnosed