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1.
Infect Immun ; 92(5): e0008024, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38534100

RESUMEN

Traditional folk treatments for the prevention and management of urinary tract infections (UTIs) and other infectious diseases often include plants and plant extracts that are rich in phenolic compounds. These have been ascribed a variety of activities, including inhibition of bacterial interactions with host cells. Here, we tested a panel of four well-studied phenolic compounds-caffeic acid phenethyl ester (CAPE), resveratrol, catechin, and epigallocatechin gallate-for the effects on host cell adherence and invasion by uropathogenic Escherichia coli (UPEC). These bacteria, which are the leading cause of UTIs, can bind and subsequently invade bladder epithelial cells via an actin-dependent process. Intracellular UPEC reservoirs within the bladder are often protected from antibiotics and host defenses and likely contribute to the development of chronic and recurrent infections. In cell culture-based assays, only resveratrol had a notable negative effect on UPEC adherence to bladder cells. However, both CAPE and resveratrol significantly inhibited UPEC entry into the host cells, coordinate with attenuated phosphorylation of the host actin regulator Focal Adhesion Kinase (FAK or PTK2) and marked increases in the numbers of focal adhesion structures. We further show that the intravesical delivery of resveratrol inhibits UPEC infiltration of the bladder mucosa in a murine UTI model and that resveratrol and CAPE can disrupt the ability of other invasive pathogens to enter host cells. Together, these results highlight the therapeutic potential of molecules like CAPE and resveratrol, which could be used to augment antibiotic treatments by restricting pathogen access to protective intracellular niches.IMPORTANCEUrinary tract infections (UTIs) are exceptionally common and increasingly difficult to treat due to the ongoing rise and spread of antibiotic-resistant pathogens. Furthermore, the primary cause of UTIs, uropathogenic Escherichia coli (UPEC), can avoid antibiotic exposure and many host defenses by invading the epithelial cells that line the bladder surface. Here, we identified two plant-derived phenolic compounds that disrupt activation of the host machinery needed for UPEC entry into bladder cells. One of these compounds, resveratrol, effectively inhibited UPEC invasion of the bladder mucosa in a mouse UTI model, and both phenolic compounds significantly reduced host cell entry by other invasive pathogens. These findings suggest that select phenolic compounds could be used to supplement existing antibacterial therapeutics by denying uropathogens shelter within host cells and tissues and help explain some of the benefits attributed to traditional plant-based medicines.


Asunto(s)
Infecciones por Escherichia coli , Quinasa 1 de Adhesión Focal , Fenoles , Extractos Vegetales , Infecciones Urinarias , Escherichia coli Uropatógena , Animales , Femenino , Humanos , Ratones , Adhesión Bacteriana/efectos de los fármacos , Ácidos Cafeicos/farmacología , Catequina/farmacología , Catequina/análogos & derivados , Línea Celular , Células Epiteliales/microbiología , Células Epiteliales/efectos de los fármacos , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/microbiología , Quinasa 1 de Adhesión Focal/metabolismo , Quinasa 1 de Adhesión Focal/antagonistas & inhibidores , Fenoles/farmacología , Alcohol Feniletílico/análogos & derivados , Extractos Vegetales/farmacología , Resveratrol/farmacología , Vejiga Urinaria/microbiología , Vejiga Urinaria/efectos de los fármacos , Vejiga Urinaria/patología , Infecciones Urinarias/microbiología , Infecciones Urinarias/tratamiento farmacológico , Escherichia coli Uropatógena/efectos de los fármacos
2.
PLoS Pathog ; 18(3): e1010365, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35324997

RESUMEN

Type I interferon (IFN) has been identified in patients with Lyme disease, and its abundant expression in joint tissues of C3H mice precedes development of Lyme arthritis. Forward genetics using C3H mice with severe Lyme arthritis and C57BL/6 (B6) mice with mild Lyme arthritis identified the Borrelia burgdorferi arthritis-associated locus 1 (Bbaa1) on chromosome 4 (Chr4) as a regulator of B. burgdorferi-induced IFNß expression and Lyme arthritis severity. B6 mice introgressed with the C3H allele for Bbaa1 (B6.C3-Bbaa1 mice) displayed increased severity of arthritis, which is initiated by myeloid lineage cells in joints. Using advanced congenic lines, the physical size of the Bbaa1 interval has been reduced to 2 Mbp, allowing for identification of potential genetic regulators. Small interfering RNA (siRNA)-mediated silencing identified Cdkn2a as the gene responsible for Bbaa1 allele-regulated induction of IFNß and IFN-stimulated genes (ISGs) in bone marrow-derived macrophages (BMDMs). The Cdkn2a-encoded p19 alternative reading frame (p19ARF) protein regulates IFNß induction in BMDMs as shown by siRNA silencing and overexpression of ARF. In vivo studies demonstrated that p19ARF contributes to joint-specific induction of IFNß and arthritis severity in B. burgdorferi-infected mice. p19ARF regulates B. burgdorferi-induced IFNß in BMDMs by stabilizing the tumor suppressor p53 and sequestering the transcriptional repressor BCL6. Our findings link p19ARF regulation of p53 and BCL6 to the severity of IFNß-induced Lyme arthritis in vivo and indicate potential novel roles for p19ARF, p53, and BCL6 in Lyme disease and other IFN hyperproduction syndromes.


Asunto(s)
Artritis , Inhibidor p16 de la Quinasa Dependiente de Ciclina , Enfermedad de Lyme , Animales , Artritis/genética , Borrelia burgdorferi , Inhibidor p16 de la Quinasa Dependiente de Ciclina/genética , Genes p16 , Interferón beta/genética , Interferón beta/metabolismo , Enfermedad de Lyme/genética , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , ARN Interferente Pequeño , Sistemas de Lectura , Proteína p53 Supresora de Tumor/genética
3.
PLoS Pathog ; 18(6): e1010582, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35700218

RESUMEN

Extra-intestinal pathogenic Escherichia coli (ExPEC) belong to a critical priority group of antibiotic resistant pathogens. ExPEC establish gut reservoirs that seed infection of the urinary tract and bloodstream, but the mechanisms of gut colonisation remain to be properly understood. Ucl fimbriae are attachment organelles that facilitate ExPEC adherence. Here, we investigated cellular receptors for Ucl fimbriae and Ucl expression to define molecular mechanisms of Ucl-mediated ExPEC colonisation of the gut. We demonstrate differential expression of Ucl fimbriae in ExPEC sequence types associated with disseminated infection. Genome editing of strains from two common sequence types, F11 (ST127) and UTI89 (ST95), identified a single nucleotide polymorphism in the ucl promoter that changes fimbriae expression via activation by the global stress-response regulator OxyR, leading to altered gut colonisation. Structure-function analysis of the Ucl fimbriae tip-adhesin (UclD) identified high-affinity glycan receptor targets, with highest affinity for sialyllacto-N-fucopentose VI, a structure likely to be expressed on the gut epithelium. Comparison of the UclD adhesin to the homologous UcaD tip-adhesin from Proteus mirabilis revealed that although they possess a similar tertiary structure, apart from lacto-N-fucopentose VI that bound to both adhesins at low-micromolar affinity, they recognize different fucose- and glucose-containing oligosaccharides. Competitive surface plasmon resonance analysis together with co-structural investigation of UcaD in complex with monosaccharides revealed a broad-specificity glycan binding pocket shared between UcaD and UclD that could accommodate these interactions. Overall, our study describes a mechanism of adaptation that augments establishment of an ExPEC gut reservoir to seed disseminated infections, providing a pathway for the development of targeted anti-adhesion therapeutics.


Asunto(s)
Infecciones por Escherichia coli , Escherichia coli Patógena Extraintestinal , Adhesinas Bacterianas/metabolismo , Adhesinas de Escherichia coli/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Infecciones por Escherichia coli/metabolismo , Escherichia coli Patógena Extraintestinal/genética , Escherichia coli Patógena Extraintestinal/metabolismo , Fimbrias Bacterianas/genética , Fimbrias Bacterianas/metabolismo , Humanos , Enfermedades Intestinales , Polisacáridos/metabolismo
4.
Infect Immun ; 89(10): e0035721, 2021 09 16.
Artículo en Inglés | MEDLINE | ID: mdl-34228495

RESUMEN

Extraintestinal pathogenic Escherichia coli (ExPEC) strains are major causes of urinary and bloodstream infections. ExPEC reservoirs are not completely understood. Some mastitis-associated E. coli (MAEC) strains carry genes associated with ExPEC virulence, including metal scavenging, immune avoidance, and host attachment functions. In this study, we investigated the role of the high-affinity zinc uptake (znuABC) system in the MAEC strain M12. Elimination of znuABC moderately decreased fitness during mouse mammary gland infections. The ΔznuABC mutant strain exhibited an unexpected growth delay in the presence of bile salts, which was alleviated by the addition of excess zinc. We isolated suppressor mutants with improved growth in bile salts, several of which no longer produced the K96 capsule made by strain M12. The addition of bile salts also reduced capsule production by strain M12 and ExPEC strain CP9, suggesting that capsule synthesis may be detrimental when bile salts are present. To better understand the role of the capsule, we compared the virulence of mastitis strain M12 with that of its unencapsulated ΔkpsCS mutant in two models of ExPEC disease. The wild-type strain successfully colonized mouse bladders and kidneys and was highly virulent in intraperitoneal infections. Conversely, the ΔkpsCS mutant was unable to colonize kidneys and was unable to cause sepsis. These results demonstrate that some MAEC strains may be capable of causing human ExPEC illness. The virulence of strain M12 in these infections is dependent on its capsule. However, capsule may interfere with zinc homeostasis in the presence of bile salts while in the digestive tract.


Asunto(s)
Cápsulas Bacterianas/metabolismo , Ácidos y Sales Biliares/metabolismo , Infecciones por Escherichia coli/metabolismo , Proteínas de Escherichia coli/metabolismo , Escherichia coli Patógena Extraintestinal/metabolismo , Mastitis/metabolismo , Zinc/metabolismo , Animales , Infecciones por Escherichia coli/microbiología , Femenino , Masculino , Mastitis/microbiología , Ratones , Ratones Endogámicos C57BL , Sepsis/metabolismo , Sepsis/microbiología , Virulencia/fisiología , Factores de Virulencia/metabolismo
5.
Transfusion ; 61(1): 225-235, 2021 01.
Artículo en Inglés | MEDLINE | ID: mdl-33151564

RESUMEN

BACKGROUND: Failure of humoral tolerance to red blood cell (RBC) antigens may lead to autoimmune hemolytic anemia (AIHA), a severe and sometimes fatal disease. Previous studies have shown that although tolerance is robust in HOD mice, autoantibodies are generated upon adoptive transfer of OTII CD4+ T cells, which are specific for an epitope contained within the HOD antigen. These data imply that antigen-presenting cells (APCs) are presenting RBC-derived autoantigen(s) and are capable of driving T-cell activation. Given that multiple APCs participate in erythrophagocytosis, we used a transgenic approach to determine which cellular subsets were required for autoantigen presentation and subsequent autoreactive T-cell activation. STUDY DESIGN AND METHODS: HOD mice, which express an RBC-specific antigen consisting of hen egg lysozyme, ovalbumin, and human blood group molecule Duffy, were bred with IAbfl/fl and Cre-expressing transgenic animals to generate mice that lack I-Ab expression on particular cell subsets. OTII CD4+ T cell proliferation was assessed in vivo in HOD+ I-Abfl/fl xCre+ mice and in vitro upon coculture with sorted APCs. RESULTS: Analysis of HOD+ I-Abfl/fl xCre+ mice demonstrated that splenic conventional dendritic cells (DCs), but not macrophages or monocytes, were required for autoantigen presentation to OTII CD4+ T cells. Subsequent in vitro coculture experiments revealed that both CD8+ and CD8- DC subsets participate in erythrophagocytosis, present RBC-derived autoantigen and stimulate autoreactive T-cell proliferation. CONCLUSION: These data suggest that if erythrocyte T-cell tolerance fails, DCs are capable of initiating autoimmune responses. As such, targeting DCs may be a fruitful strategy for AIHA therapies.


Asunto(s)
Autoantígenos/inmunología , Células Dendríticas/inmunología , Eritrocitos/inmunología , Bazo/citología , Anemia Hemolítica Autoinmune/etiología , Anemia Hemolítica Autoinmune/inmunología , Anemia Hemolítica Autoinmune/mortalidad , Animales , Autoanticuerpos , Autoinmunidad , Linfocitos T CD4-Positivos/metabolismo , Eritrocitos/metabolismo , Femenino , Proteínas de Homeodominio/metabolismo , Humanos , Tolerancia Inmunológica , Activación de Linfocitos/inmunología , Masculino , Ratones , Ratones Endogámicos C57BL/inmunología , Monocitos/inmunología
6.
J Autoimmun ; 114: 102489, 2020 11.
Artículo en Inglés | MEDLINE | ID: mdl-32507505

RESUMEN

Autoimmune hemolytic anemia (AIHA) leads to accelerated destruction of autologous red blood cells (RBCs) by autoantibodies. AIHA is a severe and sometimes fatal disease. While there are several therapeutic strategies available, there are currently no licensed treatments for AIHA and few therapeutics result in treatment-free durable remission. The etiology of primary AIHA is unknown; however, secondary AIHA occurs concurrently with lymphoproliferative disorders and infections. Additionally, AIHA is the second most common manifestation of primary immunodeficiency disorders and has been described as a side effect of checkpoint inhibitor therapy. Given the severity of AIHA and the lack of treatment options, understanding the initiation of autoimmunity is imperative. Herein, we utilized a well-described model of RBC biology to dissect how RBC-specific autoreactive T cells become educated against RBC autoantigens. We show that, unlike most autoantigens, T cells do not encounter RBC autoantigens in the thymus. Instead, when they leave the thymus as recent thymic emigrants (RTEs), they retain the ability to positively respond to RBC autoantigens; only after several weeks in circulation do RTEs become nonresponsive. Together, these data suggest that any disruption in this process would lead to breakdown of tolerance and initiation of autoimmunity. Thus, RTEs and this developmental process are potential targets to prevent and treat AIHA.


Asunto(s)
Autoinmunidad , Movimiento Celular/inmunología , Eritrocitos/inmunología , Tolerancia Inmunológica , Linfocitos T/inmunología , Timo/inmunología , Anemia Hemolítica Autoinmune/sangre , Anemia Hemolítica Autoinmune/diagnóstico , Anemia Hemolítica Autoinmune/inmunología , Anemia Hemolítica Autoinmune/terapia , Autoantígenos/inmunología , Humanos , Linfocitos T/metabolismo
7.
Transfusion ; 59(2): 744-753, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-30681727

RESUMEN

BACKGROUND: Humoral alloimmunization to human leukocyte antigen (HLA) can represent a barrier to solid-organ transplantation, can lead to a refractory state in patients requiring platelet transfusion, and can also contribute to transfusion-related acute lung injury (TRALI). While exposure to HLA-mismatched cells/tissues are generally required for HLA alloimmunization, the effect of the extent of major histocompatibility complex (MHC) mismatch between donor and recipient is poorly understood. STUDY DESIGN AND METHODS: A novel mouse was generated that allows the expression of a single MHC Class I alloantigen, Kd . Alloimmune responses to Kd were studied in C57BL/6 mice transfused with splenocytes from different donor mice, allowing the analysis of responses to Kd as an isolated alloantigen, or in the context of additional mismatched MHC molecules. Advanced tools were utilized to study responses to Kd , including T-cell receptor transgenic mice that recognize the immunodominant Kd peptide presented by C57BL/6 mice to CD4+ T cells. RESULTS: A single MHC Class I alloantigen mismatch is less immunogenic than when the same alloantigen is encountered in the context of additional mismatched MHC alloantigens. This difference is due, at least in part, to induction of CD4+ helper T cells, as the effect is overcome by increasing either mature CD4+ T-cell help through immunization or by increasing the precursor frequency of naïve CD4+ T cells by adoptive transfer from T-cell receptor transgenic donors. CONCLUSION: These findings indicate that the immunogenicity of a single alloantigen can be affected by the context in which it is encountered, demonstrating the potential for cooperative effects between different mismatched MHC alloantigens.


Asunto(s)
Plaquetas/inmunología , Antígenos de Histocompatibilidad Clase II/inmunología , Isoantígenos/inmunología , Transfusión de Plaquetas , Receptores de Antígenos de Linfocitos T/inmunología , Linfocitos T Colaboradores-Inductores/inmunología , Animales , Plaquetas/patología , Modelos Animales de Enfermedad , Antígenos de Histocompatibilidad Clase II/genética , Humanos , Isoantígenos/genética , Ratones , Ratones Transgénicos , Receptores de Antígenos de Linfocitos T/genética , Linfocitos T Colaboradores-Inductores/patología , Reacción a la Transfusión/genética , Reacción a la Transfusión/patología
8.
Clin Exp Allergy ; 48(12): 1622-1630, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-29870077

RESUMEN

BACKGROUND: Inducible laryngeal obstruction, an induced, inappropriate narrowing of the larynx, leading to symptomatic upper airway obstruction, can coexist with asthma. Accurate classification has been challenging because of overlapping symptoms and the absence of sensitive diagnostic criteria for either condition. OBJECTIVE: To evaluate patients with concomitant clinical suspicion for inducible laryngeal obstruction and asthma. We used a multidisciplinary protocol incorporating objective diagnostic criteria to determine whether asthma, inducible laryngeal obstruction, both, or neither diagnosis was present. METHODS: Consecutive patients were prospectively assessed by a laryngologist, speech pathologist and respiratory physician. Inducible laryngeal obstruction was diagnosed by visualizing paradoxical vocal fold motion either at baseline or following mannitol provocation. Asthma was diagnosed by physician assessment with objective variable airflow obstruction. Validated questionnaires for laryngeal dysfunction and relevant comorbidities were administered. RESULTS: Of 69 patients, 15 had asthma alone, 11 had inducible laryngeal obstruction alone and 14 had neither objectively demonstrated. Twenty-nine patients had both diagnoses. In 19 patients, inducible laryngeal obstruction was only seen following provocation. Among patients with inducible laryngeal obstruction, chest tightness was more frequent with concurrent asthma. Among patients with asthma, stridor was more frequent with concurrent inducible laryngeal obstruction. Cough was more frequently found in asthma alone, whereas difficulty with inspiration and symptoms triggered by psychological stress were more frequently found in inducible laryngeal obstruction alone. Patients with asthma alone had greater airflow obstruction. Relevant comorbidities were frequent (rhinitis in 85%, gastro-oesophageal reflux in 65%), and questionnaire scores for laryngeal dysfunction were abnormal. However, neither comorbidities nor questionnaires differentiated patients with or without inducible laryngeal obstruction. CONCLUSIONS AND CLINICAL RELEVANCE: In this cohort with suspected inducible laryngeal obstruction and asthma, 42% had objective evidence of both conditions. Clinical assessment, questionnaire scores and comorbidity burden were not sufficiently discriminatory for diagnosis, highlighting the necessity of objective diagnostic testing.


Asunto(s)
Obstrucción de las Vías Aéreas/complicaciones , Obstrucción de las Vías Aéreas/diagnóstico , Asma/complicaciones , Asma/diagnóstico , Enfermedades de la Laringe/complicaciones , Enfermedades de la Laringe/diagnóstico , Adolescente , Adulto , Anciano , Comorbilidad , Diagnóstico Diferencial , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Función Respiratoria , Adulto Joven
9.
Infect Immun ; 85(6)2017 06.
Artículo en Inglés | MEDLINE | ID: mdl-28373355

RESUMEN

Extraintestinal pathogenic Escherichia coli (ExPEC) strains are typically benign within the mammalian gut but can disperse to extraintestinal sites to cause diseases like urinary tract infections and sepsis. As occupation of the intestinal tract is often a prerequisite for ExPEC-mediated pathogenesis, we set out to understand how ExPEC colonizes this niche. A screen using transposon sequencing (Tn-seq) was performed to search for genes within ExPEC isolate F11 that are important for growth in intestinal mucus, which is thought to be a major source of nutrients for E. coli in the gut. Multiple genes that contribute to ExPEC fitness in mucus broth were identified, with genes that are directly or indirectly associated with fatty acid beta-oxidation pathways being especially important. One of the identified mucus-specific fitness genes encodes the rhomboid protease GlpG. In vitro, we found that the disruption of glpG had polar effects on the downstream gene glpR, which encodes a transcriptional repressor of factors that catalyze glycerol degradation. Mutation of either glpG or glpR impaired ExPEC growth in mucus and on plates containing the long-chain fatty acid oleate as the sole carbon source. In contrast, in a mouse gut colonization model in which the natural microbiota is unperturbed, the disruption of glpG but not glpR significantly reduced ExPEC survival. This work reveals a novel biological role for a rhomboid protease and highlights new avenues for defining mechanisms by which ExPEC strains colonize the mammalian gastrointestinal tract.


Asunto(s)
Proteínas de Unión al ADN/genética , Endopeptidasas/genética , Infecciones por Escherichia coli/microbiología , Proteínas de Escherichia coli/genética , Escherichia coli Patógena Extraintestinal/genética , Tracto Gastrointestinal/microbiología , Proteínas de la Membrana/genética , Animales , Escherichia coli Patógena Extraintestinal/enzimología , Femenino , Aptitud Genética , Mucosa Intestinal/metabolismo , Ratones , Ratones Endogámicos BALB C , Mutación , Proteínas Represoras/genética , Sepsis/microbiología
10.
Transfusion ; 56(4): 905-16, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26843479

RESUMEN

BACKGROUND: Generation of antibodies against red blood cell (RBC) antigens can be a clinically significant problem. The underlying mechanisms that regulate the production of RBC antibodies are only partially understood; however, factors such as inflammation significantly increase the rates of RBC antibody generation. Humoral alloimmunization begins with consumption of transfused RBCs by antigen-presenting cells (APCs). Recently, it has become appreciated that there are multiple different types of APCs. The relative contribution of APC subsets to RBC antibodies has not been described in either the quiescent or the inflamed states. STUDY DESIGN AND METHODS: To evaluate the types of APCs that consume RBCs, and how inflammation affects this process, C56Bl/6 mice were treated with polyinosinic-polycytidylic acid (poly(I:C)) to induce an inflammatory response and/or were transfused with 3,3'-dihexadecyloxacarbocyanine perchlorate-labeled syngeneic RBCs. Erythrophagocytosis (both at baseline and during inflammation) was analyzed for different subsets of macrophages (MΦ), dendritic cells (DCs), B cells, and monocytes, by a combined approach using flow cytometry and fluorescent microscopy technology. RESULTS: In four independent experiments, erythrophagocytosis at baseline was predominately performed by red pulp MΦ; however, during inflammation both plasmacytoid DCs (pDCs) and monocytes increased RBC consumption. Furthermore, pDCs up regulated MHC-II and activation markers CD80 and CD86. In addition to changing patterns of erythrophagocytosis, inflammation also led to a significant decrease in CD11c+ conventional DC populations and an increase in granulocytes. CONCLUSIONS: The nature of APCs that consume transfused RBCs is changed by inflammation. Given that APCs initiate humoral immune responses, these findings provide potential mechanistic insight into how inflammation regulates RBC alloimmunization.


Asunto(s)
Citofagocitosis/fisiología , Células Dendríticas/fisiología , Eritrocitos/fisiología , Inflamación/patología , Monocitos/fisiología , Animales , Citofagocitosis/efectos de los fármacos , Células Dendríticas/efectos de los fármacos , Eritrocitos/efectos de los fármacos , Inflamación/inmunología , Macrófagos/efectos de los fármacos , Macrófagos/inmunología , Ratones , Ratones Endogámicos C57BL , Monocitos/efectos de los fármacos , Poli I-C/inmunología , Poli I-C/farmacología , Bazo/efectos de los fármacos , Bazo/inmunología , Regulación hacia Arriba/efectos de los fármacos , Regulación hacia Arriba/inmunología
11.
Clin Rehabil ; 30(1): 53-63, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25697454

RESUMEN

OBJECTIVE: To compare the effects of attentional focus to augment balance outcomes in individuals with Parkinson's disease. DESIGN: Randomised controlled clinical trial. SETTING: University gait and balance research laboratory. PARTICIPANTS: Forty-nine individuals with idiopathic Parkinson's disease. INTERVENTIONS: Participants were randomly assigned into one of four groups (three balance intervention groups and one control). The three intervention groups all received the same 4-week balance training program augmented with either external, internal, or no focus instructions. The control group did not receive any balance training. MAIN MEASURES: Outcomes were measured at baseline, post intervention, 2-weeks post intervention, and 8-weeks post intervention and included: Sensory Organization Test, Berg Balance Scale, Self-Selected Gait Velocity, Dynamic Gait Index, Activities-Specific Balance Confidence Scale, and obstacle course completion time. RESULTS: There were no differences among the groups in trajectory over the course of the trial for all outcomes (ps ⩾ .135). All groups improved from baseline to post intervention and from baseline to 2-weeks post intervention for all outcomes (ps ⩽ .003), except Self-Selected Gait Velocity, which did not change over the course of the trial (P = .121). CONCLUSIONS: Attentional focus instructions to augment a 4-week balance training program did not result in any change over and above a control group in measures of gait and balance in individuals with Parkinson's disease. Additionally, while all four groups improved, there was no difference among the groups, including the control, suggesting that the 4-week balance training program in this trial was not effective.


Asunto(s)
Atención/fisiología , Terapia por Ejercicio/métodos , Enfermedad de Parkinson/diagnóstico , Enfermedad de Parkinson/rehabilitación , Equilibrio Postural/fisiología , Accidentes por Caídas/prevención & control , Anciano , Análisis de Varianza , Intervalos de Confianza , Terapia por Ejercicio/psicología , Femenino , Estudios de Seguimiento , Humanos , Masculino , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Resultado del Tratamiento
12.
Int J Radiat Oncol Biol Phys ; 120(1): 162-177, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38493899

RESUMEN

PURPOSE: Glioblastoma (GBM) is a lethal brain tumor. Standard-of-care treatment comprising surgery, radiation, and chemotherapy results in median survival rates of 12 to 15 months. Molecular-targeted agents identified using conventional 2-dimensional (2D) in vitro models of GBM have failed to improve outcome in patients, rendering such models inadequate for therapeutic target identification. A previously developed 3D GBM in vitro model that recapitulates key GBM clinical features and responses to molecular therapies was investigated for utility for screening novel radiation-drug combinations using gold-standard clonogenic survival as readout. METHODS AND MATERIALS: Patient-derived GBM cell lines were optimized for inclusion in a 96-well plate 3D clonogenic screening platform, ClonoScreen3D. Radiation responses of GBM cells in this system were highly reproducible and comparable to those observed in low-throughout 3D assays. The screen methodology provided quantification of candidate drug single agent activity (half maximal effective concentration or EC50) and the interaction between drug and radiation (radiation interaction ratio). RESULTS: The poly(ADP-ribose) polymerase inhibitors talazoparib, rucaparib, and olaparib each showed a significant interaction with radiation by ClonoScreen3D and were subsequently confirmed as true radiosensitizers by full clonogenic assay. Screening a panel of DNA damage response inhibitors revealed the expected propensity of these compounds to interact significantly with radiation (13/15 compounds). A second screen assessed a panel of compounds targeting pathways identified by transcriptomic analysis and demonstrated single agent activity and a previously unreported interaction with radiation of dinaciclib and cytarabine (radiation interaction ratio 1.28 and 1.90, respectively). These compounds were validated as radiosensitizers in full clonogenic assays (sensitizer enhancement ratio 1.47 and 1.35, respectively). CONCLUSIONS: The ClonoScreen3D platform was demonstrated to be a robust method to screen for single agent and radiation-drug combination activity. Using gold-standard clonogenicity, this assay is a tool for identification of radiosensitizers. We anticipate this technology will accelerate identification of novel radiation-drug combinations with genuine translational value.


Asunto(s)
Neoplasias Encefálicas , Glioblastoma , Ftalazinas , Inhibidores de Poli(ADP-Ribosa) Polimerasas , Fármacos Sensibilizantes a Radiaciones , Glioblastoma/radioterapia , Glioblastoma/patología , Humanos , Fármacos Sensibilizantes a Radiaciones/farmacología , Línea Celular Tumoral , Ftalazinas/farmacología , Ftalazinas/uso terapéutico , Neoplasias Encefálicas/radioterapia , Neoplasias Encefálicas/patología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/farmacología , Inhibidores de Poli(ADP-Ribosa) Polimerasas/uso terapéutico , Indoles/farmacología , Piperazinas/farmacología , Piperazinas/uso terapéutico , Supervivencia Celular/efectos de los fármacos , Reproducibilidad de los Resultados , Técnicas de Cultivo Tridimensional de Células/métodos
13.
EBioMedicine ; 100: 104976, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38244293

RESUMEN

BACKGROUND: Chronic cough is a prevalent and difficult to treat condition often accompanied by cough hypersensitivity, characterised by cough triggered from exposure to low level sensory stimuli. The mechanisms underlying cough hypersensitivity may involve alterations in airway sensory nerve responsivity to tussive stimuli which would be accompanied by alterations in stimulus-induced brainstem activation, measurable with functional magnetic resonance imaging (fMRI). METHODS: We investigated brainstem responses during inhalation of capsaicin and adenosine triphosphate (ATP) in 29 participants with chronic cough and 29 age- and sex-matched controls. Psychophysical testing was performed to evaluate individual sensitivities to inhaled stimuli and fMRI was used to compare neural activation in participants with cough and control participants while inhaling stimulus concentrations that evoked equivalent levels of urge-to-cough sensation. FINDINGS: Participants with chronic cough were significantly more sensitive to inhaled capsaicin and ATP and showed a change in relationship between urge-to-cough perception and cough induction. When urge-to-cough levels were matched, participants with chronic cough displayed significantly less neural activation in medullary regions known to integrate airway sensory inputs. By contrast, neural activations did not differ significantly between the two groups in cortical brain regions known to encode cough sensations whereas activation in a midbrain region of participants with chronic cough was significantly increased compared to controls. INTERPRETATION: Cough hypersensitivity in some patients may occur in brain circuits above the level of the medulla, perhaps involving midbrain regions that amplify ascending sensory signals or change the efficacy of central inhibitory control systems that ordinarily serve to filter sensory inputs. FUNDING: Supported in part by a research grant from Investigator-Initiated Studies Program of Merck Sharp & Dohme Pty Ltd. The opinions expressed in this paper are those of the authors and do not necessarily represent those of Merck Sharp & Dohme (Australia) Pty Ltd.


Asunto(s)
Capsaicina , Hipersensibilidad , Humanos , Capsaicina/efectos adversos , Tos Crónica , Tos , Tronco Encefálico/diagnóstico por imagen , Adenosina Trifosfato
14.
Gut Microbes ; 15(1): 2190308, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36949030

RESUMEN

Pathogenic subsets of Escherichia coli include diarrheagenic (DEC) strains that cause disease within the gut and extraintestinal pathogenic E. coli (ExPEC) strains that are linked with urinary tract infections, bacteremia, and other infections outside of intestinal tract. Among DEC strains is an emergent pathotype known as atypical enteropathogenic E. coli (aEPEC), which can cause severe diarrhea. Recent sequencing efforts revealed that some E. coli strains possess genetic features that are characteristic of both DEC and ExPEC isolates. BA1250 is a newly reclassified hybrid strain with characteristics of aEPEC and ExPEC. This strain was isolated from a child with diarrhea, but its genetic features indicate that it might have the capacity to cause disease at extraintestinal sites. The spectrum of adhesins encoded by hybrid strains like BA1250 are expected to be especially important in facilitating colonization of diverse niches. E. coli common pilus (ECP) is an adhesin expressed by many E. coli pathogens, but how it impacts hybrid strains has not been ascertained. Here, using zebrafish larvae as surrogate hosts to model both gut colonization and extraintestinal infections, we found that ECP can act as a multi-niche colonization and virulence factor for BA1250. Furthermore, our results indicate that ECP-related changes in activation of envelope stress response pathways may alter the fitness of BA1250. Using an in silico approach, we also delineated the broader repertoire of adhesins that are encoded by BA1250, and provide evidence that the expression of at least a few of these varies in the absence of functional ECP.


Asunto(s)
Escherichia coli Enteropatógena , Infecciones por Escherichia coli , Escherichia coli Patógena Extraintestinal , Microbioma Gastrointestinal , Animales , Escherichia coli Enteropatógena/genética , Escherichia coli Patógena Extraintestinal/genética , Fimbrias Bacterianas/genética , Virulencia/genética , Pez Cebra , Factores de Virulencia/genética , Diarrea , Adhesinas Bacterianas/genética
15.
bioRxiv ; 2023 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-38045282

RESUMEN

Traditional folk treatments for the prevention and management of urinary tract infections (UTIs) and other infectious diseases often include plants and plant extracts that are rich in phenolic and polyphenolic compounds. These have been ascribed a variety of activities, including inhibition of bacterial interactions with host cells. Here we tested a panel of four well-studied phenolic compounds - caffeic acid phenethyl ester (CAPE), resveratrol, catechin, and epigallocatechin gallate - for effects on host cell adherence and invasion by uropathogenic Escherichia coli (UPEC). These bacteria, which are the leading cause of UTIs, can bind and subsequently invade bladder epithelial cells via an actin-dependent process. Intracellular UPEC reservoirs within the bladder are often protected from antibiotics and host defenses, and likely contribute to the development of chronic and recurrent infections. Using cell culture-based assays, we found that only resveratrol had a notable negative effect on UPEC adherence to bladder cells. However, both CAPE and resveratrol significantly inhibited UPEC entry into the host cells, coordinate with attenuated phosphorylation of the host actin regulator Focal Adhesion Kinase (FAK, or PTK2) and marked increases in the numbers of focal adhesion structures. We further show that the intravesical delivery of resveratrol inhibits UPEC infiltration of the bladder mucosa in a murine UTI model, and that resveratrol and CAPE can disrupt the ability of other invasive pathogens to enter host cells. Together, these results highlight the therapeutic potential of molecules like CAPE and resveratrol, which could be used to augment antibiotic treatments by restricting pathogen access to protective intracellular niches.

16.
Clin Exp Ophthalmol ; 40(4): e208-17, 2012.
Artículo en Inglés | MEDLINE | ID: mdl-22004014

RESUMEN

BACKGROUND: Despite increasing knowledge of the genetic pathophysiology of glaucoma, mutations in known genes account for less than 15% of disease. Gene screening predominantly remains a research tool rather than an essential part of the clinical work-up. We aimed to determine the mutational spectrum and frequency in the genes implicated in glaucoma, in a range of glaucoma and 'glaucoma suspect' (GS) participants, with a positive family history. METHODS: Observational large case series. One hundred fifteen patients recruited from public hospital and private clinics had diagnoses of GS, ocular hypertension, pseudoexfoliative glaucoma (PXG) or primary open-angle glaucoma (POAG), and at least one affected family member. In a university laboratory, DNA samples were screened for mutations in all coding exons of MYOC and CYP1B1, and OPTN (exons 4, 5 and 16). WDR36 (exons 1, 4, 5, 8, 11, 13 and 17) was screened in those with CYP1B1 changes. LOXL1 risk variants were screened in PXG pedigrees. Cascade screening of family members was undertaken. RESULTS: Seven out of one hundred fifteen (6.1%) individuals had at least one pathogenic or hypomorphic CYP1B1 allele associated with GS, POAG (5) and PXG phenotypes, including two novel sequence variations (p.Ser6Gly, p.Val243Leu). No pathogenic MYOC change was detected. Five individuals (4.3%) carried an OPTN sequence variation. Three of the seven with CYP1B1 changes had polygenic changes. CONCLUSIONS: Mutational analysis of known glaucoma genes in a mixed glaucoma population replicates the reported frequency of pathogenic CYP1B1 changes. Heterozygous CYP1B1 changes occurred at a greater frequency than other genes. Glaucoma pathogenesis in the clinic setting is genetically heterogeneous and may be polygenic.


Asunto(s)
Hidrocarburo de Aril Hidroxilasas/genética , Glaucoma de Ángulo Abierto/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Aminoácido Oxidorreductasas/genética , Proteínas de Ciclo Celular , Citocromo P-450 CYP1B1 , Proteínas del Citoesqueleto/genética , Análisis Mutacional de ADN , Exones/genética , Proteínas del Ojo/genética , Femenino , Frecuencia de los Genes , Glicoproteínas/genética , Humanos , Presión Intraocular , Masculino , Proteínas de Transporte de Membrana , Persona de Mediana Edad , Linaje , Fenotipo , Factor de Transcripción TFIIIA/genética , Adulto Joven
17.
Toxins (Basel) ; 14(11)2022 11 09.
Artículo en Inglés | MEDLINE | ID: mdl-36356023

RESUMEN

Voice tremor is a common, yet debilitating symptom for patients suffering from a number of tremor-associated disorders. The key to targeting effective treatments for voice tremor requires a fundamental understanding of the pathophysiology that underpins the tremor mechanism and accurate identification of the disease in affected patients. An updated review of the literature detailing the current understanding of voice tremor (with or without essential tremor), its accurate diagnosis and targeted treatment options was conducted, with a specific focus on the role of botulinum neurotoxin. Judicious patient selection, following detailed characterisation of voice tremor qualities, is essential to optimising treatment outcomes for botulinum neurotoxin therapy, as well as other targeted therapies. Further focused investigation is required to characterise the response to targeted treatment in voice tremor patients and to guide the development of innovative treatment options.


Asunto(s)
Toxinas Botulínicas Tipo A , Temblor Esencial , Fármacos Neuromusculares , Trastornos de la Voz , Humanos , Toxinas Botulínicas Tipo A/efectos adversos , Temblor/diagnóstico , Temblor/tratamiento farmacológico , Temblor Esencial/diagnóstico , Temblor Esencial/tratamiento farmacológico , Trastornos de la Voz/diagnóstico , Trastornos de la Voz/tratamiento farmacológico
18.
Toxins (Basel) ; 14(12)2022 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-36548741

RESUMEN

Laryngeal dystonia (LD), or spasmodic dysphonia (SD), is a chronic, task-specific, focal movement disorder affecting the larynx. It interferes primarily with the essential functions of phonation and speech. LD affects patients' ability to communicate effectively and significantly diminishes their quality of life. Botulinum neurotoxin was first used as a therapeutic agent in the treatment of LD four decades ago and remains the standard of care for the treatment of LD. This article provides an overview of the clinical application of botulinum neurotoxin in the management of LD, focusing on the classification for this disorder, its pathophysiology, clinical assessment and diagnosis, the role of laryngeal electromyography and a summary of therapeutic injection techniques, including a comprehensive description of various procedural approaches, recommendations for injection sites and dosage considerations.


Asunto(s)
Toxinas Botulínicas , Disfonía , Distonía , Laringe , Humanos , Disfonía/tratamiento farmacológico , Toxinas Botulínicas/uso terapéutico , Distonía/tratamiento farmacológico , Calidad de Vida
19.
Eur J Paediatr Neurol ; 38: 47-52, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35390560

RESUMEN

BACKGROUND: Alternating hemiplegia of childhood (AHC) pathophysiology suggests predisposition to sedation and anesthesia complications. GOALS: Hypotheses: 1) AHC patients experience high rates of sedation-anesthesia complications. 2) ATP1A3 mutation genotype positivity, age, and AHC severity correlate with more severe complications. 3) Prior short QTc correlates with cardiac rhythm complications. METHODS: Analysis of 34 consecutive AHC patients who underwent sedation or anesthesia. Classification of complications: mild (not requiring intervention), moderate (intervention), severe (intervention, risk for permanent injury or potential life-threatening emergency). STATISTICS: Fisher Exact test, Spearman correlations. RESULTS: These patients underwent 129 procedures (3.79 ± 2.75 procedures/patient). Twelve (35%) experienced complications during at least one procedure. Fourteen/129 procedures (11%) manifested one or more complications (2.3% mild, 7% moderate, 1.6% severe). Of the total 20 observed complications, six (33.3%) were severe: apneas (2), seizures (2), bradycardia (1), ventricular fibrillation that responded to resuscitation (1). Moderate complications: non-life-threatening bradycardias, apneas, AHC spells or seizures. Complications occurred during sedation or anesthesia and during procedures or recovery periods. Patients with disease-associated ATP1A3 variants were more likely to have moderate or severe complications. There was no correlation between complications and age or AHC severity. Presence of prior short QTc correlated with cardiac rhythm complications. After this series was analyzed, another patient had severe recurrent laryngeal dystonia requiring tracheostomy following anesthesia with intubation. CONCLUSIONS: During sedation or anesthesia, AHC patients, particularly those with ATP1A3 variants and prior short QTc, are at risk for complications consistent with AHC pathophysiology. Increased awareness is warranted during planning, performance, and recovery from such procedures.


Asunto(s)
Anestesia , Apnea , Anestesia/efectos adversos , Hemiplejía , Humanos , Convulsiones , ATPasa Intercambiadora de Sodio-Potasio/genética
20.
J Environ Manage ; 92(10): 2781-5, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21723658

RESUMEN

New highly fluorinated monodentate and bidentate phosphine oxide compounds of the type {CF(3)(CF(2))(n)CH(2)CH(2)}(3)PO (n = 5, 9) and [{CF(3)(CF(2))(5)CH(2)CH(2)}(2)P(O)CH(2)CH(2)P(O){CH(2)CH(2)(CF(2))(5)CF(3)}] have been prepared. Their ability to extract a number of metals and radionuclides from aqueous solutions into perfluorinated solvents has been established and the extractable species investigated. All extractants extract the metals As(V), Cd(II), Co(II), Cr(VI), Hg(II), Pb(II), and Sn(II) with >75% removal. In addition, the radioisotopes (90)Sr(II), (133)Ba(II), and U(VI) have been investigated, whilst (59)Fe(III) has been used to model the extraction of plutonium. (133)Ba(II) shows a high distribution ratio for monodentate phosphine oxides, whilst for UO(2)(2+) and (59)Fe(III) bidentate phosphine oxides are superior.


Asunto(s)
Contaminantes Ambientales , Metales Pesados , Fosfinas , Radioisótopos , Solventes , Restauración y Remediación Ambiental/métodos , Halogenación , Óxidos , Sulfuros , Agua
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