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1.
Am J Physiol Gastrointest Liver Physiol ; 326(2): G120-G132, 2024 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-38014444

RESUMEN

Seladelpar, a selective peroxisome proliferator-activated receptor δ (PPARδ) agonist, improves markers of hepatic injury in human liver diseases, but histological improvement of nonalcoholic steatohepatitis (NASH) and liver fibrosis has been challenging with any single agent. To discover how complementary agents could work with seladelpar to achieve optimal outcomes, this study evaluated a variety of therapeutics (alone and in combination) in a mouse model of NASH. Mice on a high-fat amylin liver NASH (AMLN) diet were treated for 12 wk with seladelpar, GLP-1-R (glucagon-like peptide-1 receptor) agonist liraglutide, apoptosis signal-regulating kinase 1 (ASK1) inhibitor selonsertib, farnesoid X receptor (FXR) agonist obeticholic acid, and with seladelpar in combination with liraglutide or selonsertib. Seladelpar treatment markedly improved plasma markers of liver function. Seladelpar alone or in combination resulted in stark reductions in liver fibrosis (hydroxyproline, new collagen synthesis rate, mRNA indices of fibrosis, and fibrosis staining) compared with vehicle and the other single agents. Robust reductions in liver steatosis were also observed. Seladelpar produced a reorganization of metabolic gene expression, particularly for those genes promoting peroxisomal and mitochondrial lipid oxidation. In summary, substantial improvements in NASH and NASH-induced fibrosis were observed with seladelpar alone and in combination with liraglutide in this model. Broad gene expression analysis suggests seladelpar should be effective in concert with diverse mechanisms of action.NEW & NOTEWORTHY NASH is a chronic, progressive, and increasingly problematic liver disease that has been resistant to treatment with individual therapeutics. In this study using a diet-induced mouse model of NASH, we found that the PPARδ agonist seladelpar reduced fibrosis and NASH pathology alone and in combinations with a GLP-1-R agonist (liraglutide) or an ASK1 inhibitor (selonsertib). Liver transcriptome analysis comparing each agent and coadministration suggests seladelpar should be effective in combination with a variety of therapeutics.


Asunto(s)
Acetatos , Benzamidas , Terapias Complementarias , Imidazoles , Enfermedad del Hígado Graso no Alcohólico , PPAR delta , Piridinas , Humanos , Ratones , Animales , Enfermedad del Hígado Graso no Alcohólico/tratamiento farmacológico , Enfermedad del Hígado Graso no Alcohólico/metabolismo , Liraglutida/farmacología , Liraglutida/uso terapéutico , PPAR delta/metabolismo , PPAR delta/farmacología , Hígado/metabolismo , Cirrosis Hepática/metabolismo , Inflamación/metabolismo , Ratones Endogámicos C57BL
2.
Pediatr Transplant ; 28(4): e14784, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38766976

RESUMEN

BACKGROUND: The goal of this study was to assess the effect of donor type and pre-transplant immunotherapy (IST) on outcomes of hematopoietic stem cell transplantation (HSCT) for children and young adults with severe aplastic anemia (SAA). METHODS: This retrospective, multi-center study included 52 SAA patients, treated in 5 pediatric transplant programs in Florida, who received HSCT between 2010 and 2020 as the first- or second-line treatment. RESULTS: The median age at HSCT for all 52 patients was 15 years (range 1-25). The 3-year overall survival (OS) by donor type were as follows: 95% [95% CI 85.4-99] for matched related donors (MRD) (N = 24), 84% [95% CI 63.5-99] for haploidentical (N = 13), and 71% [95% CI 36-99] for matched unrelated donors (MUD) (N = 7). The 3-year OS was 81% [95% CI 69.7-99] for all patients, 90.5% [95% CI 79.5-99] for non-IST patients (N = 27), and 70% [95% CI 51-99] for IST patients (N = 24) (log-rank p = .04). Survival of haploidentical HSCT (haplo-HSCT) recipients with post-transplant cyclophosphamide (PTCy) (N = 13) was excellent for both groups: 100% for non-IST patients (N = 3) and 80% for IST patients (N = 10). The 3-year OS for patients with previous IST by donor type in groups where >5 patients were available was 78.8% [95% CI 52.3-99] for haplo-HSCT (N = 10) and 66.7% [95% CI 28.7-99] for MUD (N = 6). Although it appears that patients receiving HSCT ≥6 months after the start of IST had worse survival, the number of patients in each category was small and log-rank was not significant(p = .65). CONCLUSIONS: Patients receiving MUD and haplo-HSCT with PTCy had similar outcomes, suggesting that haplo-HSCT with PTCy could be included in randomized trials of upfront IST versus alternative donor HSCT.


Asunto(s)
Anemia Aplásica , Trasplante de Células Madre Hematopoyéticas , Humanos , Anemia Aplásica/terapia , Adolescente , Niño , Estudios Retrospectivos , Masculino , Femenino , Preescolar , Adulto Joven , Adulto , Lactante , Resultado del Tratamiento , Terapia de Inmunosupresión/métodos , Donantes de Tejidos , Inmunosupresores/uso terapéutico
3.
J Korean Med Sci ; 38(24): e197, 2023 Jun 19.
Artículo en Inglés | MEDLINE | ID: mdl-37337811

RESUMEN

Human Q fever, a zoonosis caused by Coxiella burnetii, presents with diverse clinical manifestations ranging from mild self-limited febrile illnesses to life-threatening complications such as endocarditis or vascular infection. Although acute Q fever is a benign illness with a low mortality rate, a large-scale outbreak of Q fever in the Netherlands led to concerns about the possibility of blood transfusion-related transmission or obstetric complications in pregnant women. Furthermore, a small minority (< 5%) of patients with asymptomatic or symptomatic infection progress to chronic Q fever. Chronic Q fever is fatal in 5-50% of patients if left untreated. In South Korea, Q fever in humans was designated as a notifiable infectious disease in 2006, and the number of Q fever cases has increased sharply since 2015. Nonetheless, it is still considered a neglected and under-recognized infectious disease. In this review, recent trends of human and animal Q fever in South Korea, and public health concerns regarding Q fever outbreaks are reviewed, and we consider how a One Health approach could be applied as a preventive measure to prepare for zoonotic Q fever outbreaks.


Asunto(s)
Enfermedades Transmisibles , Salud Única , Fiebre Q , Animales , Humanos , Femenino , Embarazo , Fiebre Q/epidemiología , Fiebre Q/prevención & control , Zoonosis/epidemiología , Zoonosis/prevención & control , Brotes de Enfermedades/prevención & control , República de Corea/epidemiología , Enfermedades Transmisibles/epidemiología
4.
Connect Tissue Res ; 63(5): 463-474, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-34974783

RESUMEN

Although digital image analysis methods that quantify histopathologic features have emerged, no validated quantitative methods are available to evaluate tendon injury. This study aimed to propose and validate a quantitative analysis method to identify the histopathologic features of tendon injuries. The histopathologic features of two Achilles tendon injury models (a partial full-thickness defect model and a collagenase injection model) using Sprague-Dawley rats were evaluated by semiquantitative grading and a quantitative analysis method using a digital pathology software at weeks 1 and 4 after tendon injury (six tendons per group at each time point). The outcome variables between tendon injury models and between time points were compared, and the correlation between semiquantitative scores and the results of the quantitative analysis was investigated. The proposed analysis method quantified the severity of the histopathological features after tendon injury. Quantitative analysis differentiated the cell morphology between tendon injury models and time points better than semiquantitative scoring. The results from quantitative measurements correlated significantly with the semiquantitative scores. The proposed quantitative method can be effective in evaluating the histopathology of tendon injuries.


Asunto(s)
Tendón Calcáneo , Traumatismos de los Tendones , Tendón Calcáneo/patología , Animales , Diferenciación Celular , Colagenasas , Modelos Animales de Enfermedad , Ratas , Ratas Sprague-Dawley , Traumatismos de los Tendones/patología
5.
J Prosthet Dent ; 127(2): 239-247, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-33246562

RESUMEN

STATEMENT OF PROBLEM: The fit and performance of prostheses fabricated using various computer-aided design and computer-aided manufacturing (CAD-CAM) systems have been evaluated. However, most studies were conducted in vitro, and relatively few have addressed gingival parameters and prosthesis fit under clinical conditions. PURPOSE: This clinical study aimed to compare the fit of lithium disilicate crowns produced using 3 CAD-CAM systems and evaluate clinical results up to 6 months after delivery. MATERIAL AND METHODS: Forty participants requiring a single crown were recruited. Three monolithic lithium disilicate crowns were fabricated per participant by using 3 different CAD-CAM systems (intraoral scanners, CAD software, and milling machines): CEREC group (CEREC Bluecam, CEREC AC, CEREC MC); EZIS group (EZIS PO, EZIS VR, EZIS HM); and TRIOS group (TRIOS 3, EXO-CAD, ARUM-4X). The fit of the prostheses was assessed via a silicone replica technique, and the most acceptable crown was delivered; 12 were selected from the CEREC group, 16 from the EZIS group, and 12 from the TRIOS group. Follow-up clinical examinations were performed at 1, 3, and 6 months after delivery. The Kruskal-Wallis test with the post hoc Mann-Whitney U test was conducted to analyze significant differences in crown fit and periodontal conditions among the groups (α=.05). RESULTS: The marginal gap of the CEREC group was significantly higher than that of the EZIS group, and the occlusal gap of the EZIS group was significantly lower than those of the CEREC and TRIOS groups (P<.05). Probing depth, bleeding index, and plaque index showed no intergroup differences at 6 months (P>.05). CONCLUSIONS: The lithium disilicate crowns of all groups showed clinically acceptable fit. No significant differences were found among the groups in terms of periodontal conditions after 6 months.


Asunto(s)
Adaptación Marginal Dental , Diseño de Prótesis Dental , Diseño Asistido por Computadora , Coronas , Porcelana Dental , Diseño de Prótesis Dental/métodos , Humanos
6.
J Digit Imaging ; 33(3): 607-612, 2020 06.
Artículo en Inglés | MEDLINE | ID: mdl-31939003

RESUMEN

Cardiac magnetic resonance imaging provides high spatial resolution, enabling improved extraction of important functional and morphological features for cardiovascular disease staging. Segmentation of ventricular cavities and myocardium in cardiac cine sequencing provides a basis to quantify cardiac measures such as ejection fraction. A method is presented that curtails the expense and observer bias of manual cardiac evaluation by combining semantic segmentation and disease classification into a fully automatic processing pipeline. The initial processing element consists of a robust dilated convolutional neural network architecture for voxel-wise segmentation of the myocardium and ventricular cavities. The resulting comprehensive volumetric feature matrix captures diagnostic clinical procedure data and is utilized by the final processing element to model a cardiac pathology classifier. Our approach evaluated anonymized cardiac images from a training data set of 100 patients (4 pathology groups, 1 healthy group, 20 patients per group) examined at the University Hospital of Dijon. The top average Dice index scores achieved were 0.940, 0.886, and 0.849 for structure segmentation of the left ventricle (LV), myocardium, and right ventricle (RV), respectively. A 5-ary pathology classification accuracy of 90% was recorded on an independent test set using the trained model. Performance results demonstrate the potential for advanced machine learning methods to deliver accurate, efficient, and reproducible cardiac pathological assessment.


Asunto(s)
Redes Neurales de la Computación , Semántica , Corazón , Humanos , Procesamiento de Imagen Asistido por Computador , Aprendizaje Automático , Imagen por Resonancia Magnética
7.
J Prosthet Dent ; 123(1): 15-19, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31076165

RESUMEN

A microlocking implant prosthetic system has recently been developed to address the limitations of conventional screw- and cement-retained implant-supported fixed dental prostheses. This prosthesis system consists of a precision-machined abutment and an attachment that includes zirconia balls and a nickel-titanium spring, thus providing retrievability and constant retention of the prosthesis. In addition, screw-related complications are avoided because there is no retention screw. The occlusal access hole is of a smaller diameter than that of conventional screw-retained prostheses, which is beneficial for esthetics and occlusion. It also prevents common complications of cement-retained prostheses because residual cement around the prosthesis can be removed extraorally. This article presents a clinical treatment with this new prosthetic system.


Asunto(s)
Implantes Dentales , Retención de Prótesis Dentales , Cementación , Pilares Dentales , Prótesis Dental de Soporte Implantado , Estética Dental
9.
Int J Mol Sci ; 18(8)2017 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-28786931

RESUMEN

This study was conducted to evaluate the effect of biphasic calcium phosphate (BCP) coated with reduced graphene oxide (rGO) as bone graft materials on bone regeneration. The rGO-coated BCP bone graft material was fabricatied by mixing rGO and BCP at various concentrations. The surface charge of rGO-coated BCP was measured to be -14.43 mV, which formed a static electrostatic interaction. Cell viabilities were significantly diminished at higher concentrations of ≥100 µg/mL. The calvarial defects of 48 rats were implanted rGO-coated BCPs at a weight ratio of 2:1000 (rGO2), 4:1000 (rGO4), and 10:1000 (rGO10), repectively. BCP was used as a control group. The micro-CT and histological analysis were performed to evaluate new bone formation at 2 and 8 weeks after surgery. The results showed that the new bone volume (mm³) was significantly higher in the experimental groups than in the control group. Histological analysis showed that new bone areas (%) were significantly higher in the rGO2 and rGO10 than in the control, and significantly higher in rGO4 than in the rGO2 and rGO10. Conclusively, the rGO-coated BCP was found to be effective on osteogenesis and the concentration of the composite was an important factor.


Asunto(s)
Regeneración Ósea , Sustitutos de Huesos , Materiales Biocompatibles Revestidos , Grafito/química , Hidroxiapatitas/química , Osteogénesis , Óxidos , Animales , Sustitutos de Huesos/química , Trasplante Óseo , Línea Celular , Supervivencia Celular , Masculino , Osteoblastos/citología , Osteoblastos/metabolismo , Óxidos/química , Ratas , Microtomografía por Rayos X
10.
BMC Microbiol ; 16: 70, 2016 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-27098179

RESUMEN

BACKGROUND: Brucella abortus is an intracellular pathogen which can infect and persist in host cells through multiple interactions. Above all, its interaction to host cell receptor is important to understand the pathogenic mechanisms of B. abortus. Accordingly, we demonstrated that platelet-activating factor receptor (PAFR) affects host cell response against B. abortus infection. RESULTS: First of all, B. abortus infection to macrophage induces secretion of platelet-activating factor (PAF), which is a PAFR agonist. The stimulation of PAFR by PAF remarkably increases B. abortus uptake into macrophages. It induces Janus kinase 2 (JAK2) and p38α phosphorylation, indicating that PAFR-mediated activation of JAK2 signaling leads to enhanced uptake of B. abortus. Moreover, the dynamics of F-actin polymerization revealed that PAFR-mediated B. abortus uptake is related with the reorganization of F-actin and JAK2. Upon B. abortus phagocytosis, reduced PAFR in the membrane and subsequently increased levels of PAFR colocalization with endosomes were observed which indicate that B. abortus uptake into macrophages allowed PAFR trafficking to endosomes. CONCLUSIONS: This study demonstrated that PAFR has a compelling involvement in B. abortus uptake as a promoter of phagocytosis, which is associated with JAK2 activation. Thus, our findings establish a novel insight into a receptor-related phagocytic mechanism of B. abortus.


Asunto(s)
Brucella abortus/patogenicidad , Macrófagos/inmunología , Macrófagos/microbiología , Fagocitosis , Glicoproteínas de Membrana Plaquetaria/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Citoesqueleto de Actina/metabolismo , Animales , Brucella abortus/metabolismo , Brucelosis/metabolismo , Brucelosis/microbiología , Endosomas/metabolismo , Interacciones Huésped-Patógeno , Janus Quinasa 2/metabolismo , Macrófagos/enzimología , Ratones , Células RAW 264.7 , Transducción de Señal
11.
Microb Pathog ; 83-84: 41-6, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25988974

RESUMEN

Currently, there are several serodiagnostic tools available for brucellosis, however, it is difficult to differentiate an active infection from vaccination. Hence, there is a great need to develop alternative means that can distinguish between these two conditions without utilizing lipopolysaccharide (LPS). This study was an attempt to determine the efficacy of combined recombinant Brucella (B.) abortus outer membrane proteins (rOmps) and individual rOmps in the serodiagnosis of brucellosis by enzyme linked immunosorbent assay (ELISA), utilizing both that standard tube agglutination test (TAT)-positive and -negative serum samples from Korean native cattle. The results are very interesting and promising because the combined rOmp antigens used in the study were highly reactive with the TAT-positive serum samples. The combined rOmps sensitivity, specificity and accuracy were 215/232 (92.67%), 294/298 (98.66%) and 509/530 (96.04%), respectively. While these results are preliminary, the tests performed have very high potential in the serodiagnosis of brucellosis and likewise, the combined rOmps can be used for future vaccine production.


Asunto(s)
Anticuerpos Antibacterianos/sangre , Antígenos Bacterianos/inmunología , Proteínas de la Membrana Bacteriana Externa/inmunología , Brucelosis Bovina/diagnóstico , Proteínas Recombinantes/inmunología , Pruebas Serológicas/métodos , Medicina Veterinaria/métodos , Pruebas de Aglutinación , Animales , Antígenos Bacterianos/genética , Proteínas de la Membrana Bacteriana Externa/genética , Bovinos , Ensayo de Inmunoadsorción Enzimática/métodos , Proteínas Recombinantes/genética , República de Corea , Sensibilidad y Especificidad
12.
Vet Res ; 46: 17, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25885057

RESUMEN

Brucellosis is a vital zoonotic disease caused by Brucella, which infects a wide range of animals and humans. Accurate diagnosis and reliable vaccination can control brucellosis in domestic animals. This study examined novel immunogenic proteins that can be used to detect Brucella abortus infection or as an effective subcellular vaccine. In an immunoproteomic assay, 55 immunodominant proteins from B. abortus 544 were observed using two dimensional electrophoresis (2DE) and immunoblot profiles with antisera from B. abortus-infected cattle at the early (week 3), middle (week 7), and late (week 10) periods, after excluding protein spots reacting with antisera from Yersinia enterocolitica O:9-infected and non-infected cattle. Twenty-three selected immunodominant proteins whose spots were observed at all three infection periods were identified using MALDI-MS/MS. Most of these proteins identified by immunoblot and mass spectrometry were determined by their subcellular localization and predicted function. We suggest that the detection of prominent immunogenic proteins during the infection period can support the development of advanced diagnostic methods with high specificity and accuracy; subsidiarily, these proteins can provide supporting data to aid in developing novel vaccine candidates.


Asunto(s)
Antígenos Bacterianos/inmunología , Proteínas Bacterianas/inmunología , Brucella abortus/inmunología , Brucelosis Bovina/inmunología , Sueros Inmunes/inmunología , Epítopos Inmunodominantes/inmunología , Animales , Bovinos , Femenino , Immunoblotting/veterinaria , Espectrometría de Masa por Láser de Matriz Asistida de Ionización Desorción/veterinaria , Espectrometría de Masas en Tándem/veterinaria
13.
J Biol Chem ; 288(39): 28049-57, 2013 Sep 27.
Artículo en Inglés | MEDLINE | ID: mdl-23940042

RESUMEN

Lipid raft-associated clathrin is essential for host-pathogen interactions during infection. Brucella abortus is an intracellular pathogen that circumvents host defenses, but little is known about the precise infection mechanisms that involve interaction with lipid raft-associated mediators. The aim of this study was to elucidate the clathrin-mediated phagocytic mechanisms of B. abortus. The clathrin dependence of B. abortus infection in HeLa cells was investigated using an infection assay and immunofluorescence microscopy. The redistribution of clathrin in the membrane and in phagosomes was investigated using sucrose gradient fractionation of lipid rafts and the isolation of B. abortus-containing vacuoles, respectively. Clathrin and dynamin were concentrated into lipid rafts during B. abortus infection, and the entry and intracellular survival of B. abortus within HeLa cells were abrogated by clathrin inhibition. Clathrin disruption decreased actin polymerization and the colocalization of B. abortus-containing vacuoles with clathrin and Rab5 but not lysosome-associated membrane protein 1 (LAMP-1). Thus, our data demonstrate that clathrin plays a fundamental role in the entry and intracellular survival of B. abortus via interaction with lipid rafts and actin rearrangement. This process facilitates the early intracellular trafficking of B. abortus to safe replicative vacuoles.


Asunto(s)
Brucella abortus/fisiología , Clatrina/metabolismo , Regulación Enzimológica de la Expresión Génica , Fagocitosis , Proteínas de Unión al GTP rab5/metabolismo , Actinas/química , Transporte Biológico , Células HeLa , Humanos , Proteína 1 de la Membrana Asociada a los Lisosomas/metabolismo , Microdominios de Membrana/química , Microscopía Fluorescente , Fagosomas/metabolismo , Fagosomas/microbiología , Polimerizacion , ARN Interferente Pequeño/metabolismo
14.
Korean J Parasitol ; 52(3): 325-9, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25031477

RESUMEN

The phylogenetic relationships of the 3 Neodiplostomum spp. (Digenea: Neodiplostomidae) occurring in Korea (N. seoulense, N. leei, and N. boryongense) were analyzed using the partial mitochondrial cytochrome c oxidase subunit 1 (CO1) gene. The adult flukes were recovered from Sprague-Dawley rats (N. seoulense) and newborn chicks (N. leei and N. boryongense) experimentally infected with the neodiplostomula from the grass snake, Rhabdophis tigrinus tigrinus. The genomic DNA was amplified using specific primers, and the sequence of CO1 was obtained. According to the results, the pairwise similarity was 96.1% between N. boryongense and N. seoulense, but was 95.0% between N. boryongense and N. leei and 94.2% between N. leei and N. seoulense. The results demonstrated a closer phylogenetic relationship between N. seoulense and N. boryongense. This high relationship of N. seoulense and N. boryongense may be related to their similar morphologic features including the limited distribution of vitellaria and the presence of a genital cone. N. leei is distinct on the other hand with an extensive distribution of vitellaria and the absence of a genital cone.


Asunto(s)
Colubridae/parasitología , Complejo IV de Transporte de Electrones/genética , Trematodos/clasificación , Trematodos/genética , Animales , Secuencia de Bases , Pollos , Análisis por Conglomerados , ADN de Helmintos/química , ADN de Helmintos/genética , Femenino , Corea (Geográfico) , Datos de Secuencia Molecular , Filogenia , Ratas Sprague-Dawley , Análisis de Secuencia de ADN , Homología de Secuencia de Ácido Nucleico
15.
Plant Pathol J ; 40(2): 151-159, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38606445

RESUMEN

Bacterial soft rot caused by Pectobacterium carotovorum subsp. carotovorum (Pcc) is one of the most severe diseases in radish cultivation. To control this plant disease, the most effective method has been known to cultivate resistant cultivars. Previously, we developed an efficient bioassay method for investigating resistance levels with 21 resistant and moderately resistant cultivars of radish against a strain Pcc KACC 10421. In this study, our research expanded to investigate the resistance of radish cultivars against six Pcc strains, KACC 10225, KACC 10421, ATCC 12312, ATCC 15713, LY34, and ECC 301365. To this end, the virulence of the six Pcc strains was determined based on the development of bacterial soft rot in seedlings of four susceptible radish cultivars. The results showed that the Pcc strains exhibited different virulence in the susceptible cultivars. To explore the race differentiation of Pcc strains corresponding to the resistance in radish cultivars, we investigated the occurrence of bacterial soft rot caused by the six Pcc strains on the 21 resistant and moderate resistant cultivars. Our results showed that the average values of the area under the disease progress curve were positively correlated with the virulence of the strains and the number of resistant cultivars decreased as the virulence of Pcc strains increased. Taken together, our results suggest that the resistance to Pcc of the radish cultivars commercialized in Korea is more likely affected by the virulence of Pcc strains rather than by race differentiation of Pcc.

16.
Infect Immun ; 81(7): 2448-58, 2013 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-23630962

RESUMEN

Brucella abortus is an intracellular pathogen that uses a crafty strategy to invade and proliferate within host cells, but the distinct signaling pathways associated with phagocytic mechanisms of B. abortus remain unclear. The present study was performed to test the hypothesis that Toll-like receptor 4 (TLR4)-linked signaling interacting with Janus kinase 2 (JAK2) plays an essential role in B. abortus phagocytosis by macrophages. The effects of TLR4-JAK2 signaling on B. abortus phagocytosis in murine macrophage RAW 264.7 cells were observed through an infection assay and confocal microscopy. We determined that the uptake of B. abortus was negatively affected by the dysfunction of TLR4 and JAK2. F-actin polymerization detected by flow cytometry and F-actin assay was amplified for B. abortus entry, whereas that event was attenuated by the disruption of TLR4 and JAK2. Importantly, JAK2 phosphorylation and actin skeleton reorganization were suppressed immediately after B. abortus infection in bone marrow-derived macrophages (BMDMs) from TLR4(-/-) mice, showing the cooperation of JAK2 with TLR4. Furthermore, small GTPase Cdc42 participated in the intermediate pathway of TLR4-JAK2 signaling on B. abortus phagocytosis. Consequently, TLR4-associated JAK2 activation in the early cellular signaling events plays a pivotal role in B. abortus-induced phagocytic processes in macrophages, implying the pathogenic significance of JAK2-mediated entry. Here, we elucidate that this specific phagocytic mechanism of B. abortus might provide achievable strategies for inhibiting B. abortus invasion.


Asunto(s)
Brucella abortus/metabolismo , Janus Quinasa 2/metabolismo , Macrófagos/microbiología , Fagocitosis , Receptor Toll-Like 4/metabolismo , Citoesqueleto de Actina/metabolismo , Actinas/metabolismo , Animales , Brucella abortus/patogenicidad , Brucelosis/metabolismo , Brucelosis/microbiología , Línea Celular , Activación Enzimática , Citometría de Flujo , Interacciones Huésped-Patógeno , Janus Quinasa 2/genética , Macrófagos/enzimología , Ratones , Ratones Endogámicos C3H , Microscopía Confocal , Polimerizacion , ARN Interferente Pequeño/genética , ARN Interferente Pequeño/metabolismo , Receptor Toll-Like 4/genética , Proteína de Unión al GTP cdc42/genética , Proteína de Unión al GTP cdc42/metabolismo
17.
Microb Pathog ; 54: 34-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23006628

RESUMEN

Brucella abortus, the causative agent of brucellosis, can survive and replicate within host cells. Understanding bacterial virulence factors and bacteria-host cell interactions is critical for controlling brucellosis. However, little is known regarding the pathogenic mechanisms of brucellosis. A lipoprotein mutant (Gene Bank ID: 3339351) of B. abortus showed a lower rate of intracellular replication than did the wild-type strain in HeLa cells and RAW 264.7 macrophages. The adherent activity of the lipoprotein mutant was slightly increased compared to that of the wild-type strain in HeLa cells. After infection into macrophages, the lipoprotein mutant co-localized with either late endosomes or lysosomes. In mice infected with the lipoprotein mutant, fewer lipoprotein mutants were recovered from the spleen at 8 weeks post-infection compared to the wild-type strain. The ability to protect the lipoprotein mutant against infection by the virulent B. abortus strain 544 was similar to that of strain RB51. Our results indicate that the B. abortus lipoprotein is an important factor for survival within phagocytes and mice, and the B. abortus lipoprotein mutant may help improve live vaccines used to control brucellosis.


Asunto(s)
Brucella abortus/patogenicidad , Brucelosis/microbiología , Brucelosis/patología , Lipoproteínas/metabolismo , Factores de Virulencia/metabolismo , Animales , Carga Bacteriana , Brucella abortus/crecimiento & desarrollo , Línea Celular , Modelos Animales de Enfermedad , Células Epiteliales/microbiología , Femenino , Eliminación de Gen , Humanos , Lipoproteínas/genética , Macrófagos/microbiología , Ratones , Ratones Endogámicos BALB C , Bazo/microbiología , Factores de Virulencia/genética
18.
J Infect Dis ; 205(3): 445-52, 2012 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-22158566

RESUMEN

BACKGROUND: Brucella abortus can proliferate within professional and nonprofessional phagocytic host cells and thereby successfully bypass the bacteriocidal effects of phagocytes. However, the intracellular survival mechanism and factors of virulence are not fully understood. METHODS: We have investigated the role of the regulator of G protein signaling 2 (RGS2), an intracellular calcium ([Ca(2+)](i)) regulator of the host cell, in the intracellular survival of B. abortus within phagocytes. RESULTS: B. abortus infection markedly induced RGS2 messenger RNA expression in early phase and increased the [Ca(2+)](i) level up to 24 hours postinfection within macrophages from wild-type mice. The [Ca(2+)](i) level, however, was not influenced by B. abortus infection within macrophages from RGS2-deficient mice. Furthermore, B. abortus survival was reduced within RGS2-deficient macrophages, and hence bacterial proliferation was inhibited in RGS2-deficient mice. Moreover, treatment with the Ca(2+) chelator ethylenediaminetetraacetic acid (EDTA) or 1,2-bis-(2-amino-phenoxy)ethane-N,N,N',N'-tetraacetic acid acetoxymethyl ester (BAPTA-AM) and the L-type Ca(2+) channel-blocking agent nifedipine or genistein also showed a reduced intracellular replication of B. abortus within macrophages. CONCLUSION: These results indicate that B. abortus infection induces host RGS2 expression and that up-regulation of [Ca(2+)](i) levels is an essential factor for the intracellular survival of B. abortus within phagocytes.


Asunto(s)
Brucella abortus/crecimiento & desarrollo , Calcio/metabolismo , Cationes Bivalentes/metabolismo , Citosol/microbiología , Fagocitos/microbiología , Proteínas RGS/metabolismo , Animales , Brucella abortus/fisiología , Supervivencia Celular , Recuento de Colonia Microbiana , Citosol/química , Eliminación de Gen , Perfilación de la Expresión Génica , Masculino , Ratones , Ratones Endogámicos C57BL , Fagocitos/química , Fagocitos/metabolismo , Proteínas RGS/genética , Bazo/microbiología , Bazo/patología
19.
Ann Dermatol ; 35(Suppl 2): S256-S259, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-38061716

RESUMEN

Lichen planus (LP) is a chronic inflammatory disease of the skin and mucosa. Of the various types, the hypertrophic type is characterized by thickened, purplish hyperkeratotic plaques and nodules. The course of hypertrophic LP tends to be more chronic than those of other types. A 12-year-old girl presented with a 2-year history of warty papules and plaques in a zosteriform configuration along one flank. Histopathology revealed hyperkeratosis and papillomatosis with wedge-shaped hypergranulosis. A lichenoid lymphocytic infiltrate with vacuolar change in the basal layer was evident. She was prescribed oral doxycycline, a topical corticosteroid, and tacrolimus. After 7 weeks, the skin lesions became significantly flattened and faded. LP is less common but more severe in children than in adults. The unilateral, linear hypertrophic type of LP is uncommon. Herein, we report a rare case of linear hypertrophic LP in a child.

20.
Avian Pathol ; 41(4): 403-7, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22834556

RESUMEN

The anticoccidial effects of Galla Rhois (GR) powder, which contains a major tannin-derived component of 52.7%, were evaluated in chickens following oral infection with Eimeria tenella. One-day-old chickens were assigned to five groups (control, unsupplemented, GR 0.5% supplemented [GRS 0.5%], GRS 1.0% [GRS 1.0%] and salinomycin supplemented [SS]). The chickens were fed a standard diet supplemented or not supplemented with GR or salinomycin for 10 days prior to infection. The birds received the supplemented diets continuously until 10 days post infection. The effects of GR on a E. tenella infection were evaluated by several parameters, including body weight gain, feed intake, oocyst excretion, bloody diarrhoea, and lesion scores. Infected chickens on the GRS and SS diets had a relatively moderate body weight loss (reduction ratio < 15%) and improved feed conversion. GRS and SS chickens produced significantly fewer faecal oocysts (P<0.05) and showed milder bloody diarrhoea compared with the E. tenella-infected control group. Furthermore, the lesion scores of both the GRS 0.5% and GRS 1.0% groups were significantly lower than the scores of the unsupplemented group on day 5 post infection. The lesion scores for the GR groups were similar to the scores for the SS group. In conclusion, this study suggests that GR appears to be as efficacious as salinomycin against E. tenella infection. GR supplementation leads to a reduction in infected chickens, although infected chickens are still affected compared with the uninfected control group. GR-based diets may be beneficial in preventing or treating coccidial infections in poultry.


Asunto(s)
Pollos , Coccidiosis/veterinaria , Coccidiostáticos/farmacología , Eimeria tenella/efectos de los fármacos , Extractos Vegetales/farmacología , Enfermedades de las Aves de Corral/tratamiento farmacológico , Alimentación Animal , Animales , Peso Corporal , Coccidiosis/tratamiento farmacológico , Coccidiosis/parasitología , Coccidiosis/prevención & control , Coccidiostáticos/uso terapéutico , Diarrea/veterinaria , Suplementos Dietéticos , Heces/parasitología , Femenino , Masculino , Oocistos , Extractos Vegetales/uso terapéutico , Enfermedades de las Aves de Corral/parasitología , Enfermedades de las Aves de Corral/prevención & control , Piranos/farmacología , Piranos/uso terapéutico , Organismos Libres de Patógenos Específicos , Aumento de Peso , Pérdida de Peso
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