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1.
Immunity ; 56(9): 2152-2171.e13, 2023 09 12.
Artículo en Inglés | MEDLINE | ID: mdl-37582369

RESUMEN

Microglia phenotypes are highly regulated by the brain environment, but the transcriptional networks that specify the maturation of human microglia are poorly understood. Here, we characterized stage-specific transcriptomes and epigenetic landscapes of fetal and postnatal human microglia and acquired corresponding data in induced pluripotent stem cell (iPSC)-derived microglia, in cerebral organoids, and following engraftment into humanized mice. Parallel development of computational approaches that considered transcription factor (TF) co-occurrence and enhancer activity allowed prediction of shared and state-specific gene regulatory networks associated with fetal and postnatal microglia. Additionally, many features of the human fetal-to-postnatal transition were recapitulated in a time-dependent manner following the engraftment of iPSC cells into humanized mice. These data and accompanying computational approaches will facilitate further efforts to elucidate mechanisms by which human microglia acquire stage- and disease-specific phenotypes.


Asunto(s)
Células Madre Pluripotentes Inducidas , Microglía , Humanos , Ratones , Animales , Redes Reguladoras de Genes , Encéfalo , Regulación de la Expresión Génica
2.
Am J Hum Genet ; 111(4): 729-741, 2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38579670

RESUMEN

Glutamine synthetase (GS), encoded by GLUL, catalyzes the conversion of glutamate to glutamine. GS is pivotal for the generation of the neurotransmitters glutamate and gamma-aminobutyric acid and is the primary mechanism of ammonia detoxification in the brain. GS levels are regulated post-translationally by an N-terminal degron that enables the ubiquitin-mediated degradation of GS in a glutamine-induced manner. GS deficiency in humans is known to lead to neurological defects and death in infancy, yet how dysregulation of the degron-mediated control of GS levels might affect neurodevelopment is unknown. We ascertained nine individuals with severe developmental delay, seizures, and white matter abnormalities but normal plasma and cerebrospinal fluid biochemistry with de novo variants in GLUL. Seven out of nine were start-loss variants and two out of nine disrupted 5' UTR splicing resulting in splice exclusion of the initiation codon. Using transfection-based expression systems and mass spectrometry, these variants were shown to lead to translation initiation of GS from methionine 18, downstream of the N-terminal degron motif, resulting in a protein that is stable and enzymatically competent but insensitive to negative feedback by glutamine. Analysis of human single-cell transcriptomes demonstrated that GLUL is widely expressed in neuro- and glial-progenitor cells and mature astrocytes but not in post-mitotic neurons. One individual with a start-loss GLUL variant demonstrated periventricular nodular heterotopia, a neuronal migration disorder, yet overexpression of stabilized GS in mice using in utero electroporation demonstrated no migratory deficits. These findings underline the importance of tight regulation of glutamine metabolism during neurodevelopment in humans.


Asunto(s)
Epilepsia Generalizada , Glutamato-Amoníaco Ligasa , Glutamina , Animales , Humanos , Ratones , Encéfalo/metabolismo , Epilepsia Generalizada/genética , Glutamato-Amoníaco Ligasa/genética , Glutamato-Amoníaco Ligasa/metabolismo , Glutamatos/metabolismo , Glutamina/genética , Glutamina/metabolismo
3.
Gastroenterology ; 166(4): 631-644.e17, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38211712

RESUMEN

BACKGROUND & AIMS: The incidence of Crohn's disease (CD) continues to increase worldwide. The contribution of CD4+ cell populations remains to be elucidated. We aimed to provide an in-depth transcriptional assessment of CD4+ T cells driving chronic inflammation in CD. METHODS: We performed single-cell RNA-sequencing in CD4+ T cells isolated from ileal biopsies of patients with CD compared with healthy individuals. Cells underwent clustering analysis, followed by analysis of gene signaling networks. We overlapped our differentially expressed genes with publicly available microarray data sets and performed functional in vitro studies, including an in vitro suppression assay and organoid systems, to model gene expression changes observed in CD regulatory T (Treg) cells and to test predicted therapeutics. RESULTS: We identified 5 distinct FOXP3+ regulatory Treg subpopulations. Tregs isolated from healthy controls represent the origin of pseudotemporal development into inflammation-associated subtypes. These proinflammatory Tregs displayed a unique responsiveness to tumor necrosis factor-α signaling with impaired suppressive activity in vitro and an elevated cytokine response in an organoid coculture system. As predicted in silico, the histone deacetylase inhibitor vorinostat normalized gene expression patterns, rescuing the suppressive function of FOXP3+ cells in vitro. CONCLUSIONS: We identified a novel, proinflammatory FOXP3+ T cell subpopulation in patients with CD and developed a pipeline to specifically target these cells using the US Food and Drug Administration-approved drug vorinostat.


Asunto(s)
Enfermedad de Crohn , Humanos , Enfermedad de Crohn/tratamiento farmacológico , Enfermedad de Crohn/genética , Enfermedad de Crohn/metabolismo , Vorinostat/metabolismo , Linfocitos T Reguladores/metabolismo , Inflamación/metabolismo , Factores de Transcripción Forkhead/genética , Factores de Transcripción Forkhead/metabolismo
4.
Gastroenterology ; 164(2): 256-271.e10, 2023 02.
Artículo en Inglés | MEDLINE | ID: mdl-36272457

RESUMEN

BACKGROUND & AIMS: Although T-cell intrinsic expression of G9a has been associated with murine intestinal inflammation, mechanistic insight into the role of this methyltransferase in human T-cell differentiation is ill defined, and manipulation of G9a function for therapeutic use against inflammatory disorders is unexplored. METHODS: Human naive T cells were isolated from peripheral blood and differentiated in vitro in the presence of a G9a inhibitor (UNC0642) before being characterized via the transcriptome (RNA sequencing), chromatin accessibility (assay for transposase-accessible chromatin by sequencing), protein expression (cytometry by time of flight, flow cytometry), metabolism (mitochondrial stress test, ultrahigh performance liquid chromatography-tandem mas spectroscopy) and function (T-cell suppression assay). The in vivo role of G9a was assessed using 3 murine models. RESULTS: We discovered that pharmacologic inhibition of G9a enzymatic function in human CD4 T cells led to spontaneous generation of FOXP3+ T cells (G9a-inibitors-T regulatory cells [Tregs]) in vitro that faithfully reproduce human Tregs, functionally and phenotypically. Mechanistically, G9a inhibition altered the transcriptional regulation of genes involved in lipid biosynthesis in T cells, resulting in increased intracellular cholesterol. Metabolomic profiling of G9a-inibitors-Tregs confirmed elevated lipid pathways that support Treg development through oxidative phosphorylation and enhanced lipid membrane composition. Pharmacologic G9a inhibition promoted Treg expansion in vivo upon antigen (gliadin) stimulation and ameliorated acute trinitrobenzene sulfonic acid-induced colitis secondary to tissue-specific Treg development. Finally, Tregs lacking G9a expression (G9a-knockout Tregs) remain functional chronically and can rescue T-cell transfer-induced colitis. CONCLUSION: G9a inhibition promotes cholesterol metabolism in T cells, favoring a metabolic profile that facilitates Treg development in vitro and in vivo. Our data support the potential use of G9a inhibitors in the treatment of immune-mediated conditions including inflammatory bowel disease.


Asunto(s)
Linfocitos T CD4-Positivos , Colitis , Ratones , Humanos , Animales , Metabolismo de los Lípidos , Linfocitos T Reguladores/metabolismo , Colitis/inducido químicamente , Colitis/tratamiento farmacológico , Colitis/genética , Cromatina , Inflamación , Colesterol , Lípidos , Factores de Transcripción Forkhead/metabolismo
5.
Int J Mol Sci ; 25(8)2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38673850

RESUMEN

Changes during the production cycle of dairy cattle can leave these animals susceptible to oxidative stress and reduced antioxidant health. In particular, the periparturient period, when dairy cows must rapidly adapt to the sudden metabolic demands of lactation, is a period when the production of damaging free radicals can overwhelm the natural antioxidant systems, potentially leading to tissue damage and reduced milk production. Central to the protection against free radical damage and antioxidant defense is the transcription factor NRF2, which activates an array of genes associated with antioxidant functions and cell survival. The objective of this study was to evaluate the effect that two natural NRF2 modulators, the NRF2 agonist sulforaphane (SFN) and the antagonist brusatol (BRU), have on the transcriptome of immortalized bovine mammary alveolar cells (MACT) using both the RT-qPCR of putative NRF2 target genes, as well as RNA sequencing approaches. The treatment of cells with SFN resulted in the activation of many putative NRF2 target genes and the upregulation of genes associated with pathways involved in cell survival, metabolism, and antioxidant function while suppressing the expression of genes related to cellular senescence and DNA repair. In contrast, the treatment of cells with BRU resulted in the upregulation of genes associated with inflammation, cellular stress, and apoptosis while suppressing the transcription of genes involved in various metabolic processes. The analysis also revealed several novel putative NRF2 target genes in bovine. In conclusion, these data indicate that the treatment of cells with SFN and BRU may be effective at modulating the NRF2 transcriptional network, but additional effects associated with cellular stress and metabolism may complicate the effectiveness of these compounds to improve antioxidant health in dairy cattle via nutrigenomic approaches.


Asunto(s)
Isotiocianatos , Factor 2 Relacionado con NF-E2 , Cuassinas , Sulfóxidos , Transcriptoma , Animales , Bovinos , Factor 2 Relacionado con NF-E2/metabolismo , Factor 2 Relacionado con NF-E2/genética , Isotiocianatos/farmacología , Cuassinas/farmacología , Sulfóxidos/farmacología , Transcriptoma/efectos de los fármacos , Femenino , Glándulas Mamarias Animales/metabolismo , Glándulas Mamarias Animales/citología , Glándulas Mamarias Animales/efectos de los fármacos , Células Epiteliales Alveolares/metabolismo , Células Epiteliales Alveolares/efectos de los fármacos , Antioxidantes/farmacología , Antioxidantes/metabolismo , Simulación por Computador , Estrés Oxidativo/efectos de los fármacos , Regulación de la Expresión Génica/efectos de los fármacos
6.
J Surg Orthop Adv ; 33(1): 49-52, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38815079

RESUMEN

Children with cerebral palsy (CP) and those with avascular necosis (AVN) after treatment of developmental hip dysplasia (DDH) are at risk of developing coxa valga. Proximal femur guided growth is a minimally invasive option to correct this deformity. A systematic review of articles that described treatment of coxa valga with proximal femur guided growth (PFGG) and reporting on primary radiographic outcomes, demographic variables, surgical variables and complications. One hundred and seventy-nine hips underwent PFGG (117 with CP and 62 with lateral overgrowth). Average age at surgery was 8.1 years; average follow-up was 52.5 months. Migration percentage improved from 11.2% (p < 0.0001). Neck-shaft angle improved by 11.9° (p < 0.0001). The most common complication was screw growth out of the physis (30% of cases). PFGG can correct coxa valga, improve radiographic parameters, and in children with CP prevent further subluxation. This technique modulates proximal femur growth, induces changes to the acetabulum and can correct valgus deformity. Evidence Level III. (Journal of Surgical Orthopaedic Advances 32(4):049-052, 2024).


Asunto(s)
Parálisis Cerebral , Fémur , Humanos , Niño , Fémur/diagnóstico por imagen , Coxa Valga/diagnóstico por imagen , Coxa Valga/etiología , Displasia del Desarrollo de la Cadera/cirugía , Displasia del Desarrollo de la Cadera/diagnóstico por imagen , Luxación Congénita de la Cadera/cirugía , Luxación Congénita de la Cadera/diagnóstico por imagen
7.
Am J Hum Genet ; 107(6): 1149-1156, 2020 12 03.
Artículo en Inglés | MEDLINE | ID: mdl-33186543

RESUMEN

The Congenital Dyserythropoietic Anemia (CDA) Registry was established with the goal to facilitate investigations of natural history, biology, and molecular pathogenetic mechanisms of CDA. Three unrelated individuals enrolled in the registry had a syndrome characterized by CDA and severe neurodevelopmental delay. They were found to have missense mutations in VPS4A, a gene coding for an ATPase that regulates the ESCRT-III machinery in a variety of cellular processes including cell division, endosomal vesicle trafficking, and viral budding. Bone marrow studies showed binucleated erythroblasts and erythroblasts with cytoplasmic bridges indicating abnormal cytokinesis and abscission. Circulating red blood cells were found to retain transferrin receptor (CD71) in their membrane, demonstrating that VPS4A is critical for normal reticulocyte maturation. Using proband-derived induced pluripotent stem cells (iPSCs), we have successfully modeled the hematologic aspects of this syndrome in vitro, recapitulating their dyserythropoietic phenotype. Our findings demonstrate that VPS4A mutations cause cytokinesis and trafficking defects leading to a human disease with detrimental effects to erythropoiesis and neurodevelopment.


Asunto(s)
ATPasas Asociadas con Actividades Celulares Diversas/genética , Anemia Diseritropoyética Congénita/genética , Complejos de Clasificación Endosomal Requeridos para el Transporte/genética , ATPasas de Translocación de Protón Vacuolares/genética , Adenosina Trifosfatasas/metabolismo , Anemia Diseritropoyética Congénita/patología , Médula Ósea/patología , Células de la Médula Ósea/metabolismo , Niño , Preescolar , Citocinesis , Endosomas/metabolismo , Eritroblastos/metabolismo , Eritrocitos/citología , Eritropoyesis , Femenino , Humanos , Células Madre Pluripotentes Inducidas/citología , Masculino , Trastornos del Neurodesarrollo/metabolismo , Fenotipo , Transporte de Proteínas , Reticulocitos/citología
8.
Surgeon ; 21(3): e97-e103, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35606259

RESUMEN

INTRODUCTION: Despite advances in oncology therapies and surgical techniques, survival from oesophagogastric cancer remains low. Poorer cancer outcomes and survival for rural dwellers is documented worldwide and has been an area of focus in Scotland since 2007 when changes to suspected cancer national referral guidelines and governmental mandates on delivering remote and rural healthcare occurred. Whether these changes in clinical practice has impacted upon upper gastrointestinal cancer remains unclear. METHODS: A prospective, single-centre observation study was performed. Data from the regional oesophagogastric cancer MDT between 2013 and 2019 were included. The Scottish Index of Multiple Deprivation 2020 tool provided a rurality code (1 or 2) based on patient postcode at time of referral. Survival outcomes for urban and rural patients were compared across demographic factors, disease factors and stage at presentation. RESULTS: A total of 1038 patients were included in this study. There was no significant difference between rural and urban groups in terms of sex of patient, age at diagnosis, cancer location, or tumour stage. Furthermore, no difference was identified between those commenced on a radical therapy with other treatment plans. Despite this, rurality predicted for an improved outcome on survival analysis (p = 0.012) and this was independent of other factors on multivariable analysis (HR = 0.78, 95%CI 0.66-0.98; p = 0.032). DISCUSSION: The difference in survival demonstrated here between urban and rural groups is not easily explained but may represent improvements to rural access to healthcare delivered as a result of Scottish Government reports.


Asunto(s)
Neoplasias , Humanos , Estudios de Cohortes , Estudios Prospectivos , Población Rural , Análisis de Supervivencia , Escocia/epidemiología
9.
J Surg Orthop Adv ; 32(1): 9-13, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37185070

RESUMEN

Treatment of medial epicondyle fractures is controversial in pediatric orthopaedics with a recent trend towards operative fixation in overhead athletes. We performed a systematic review to compare outcomes in operative and non-operatively overhead athletes. A systematic review of the literature was performed. Articles investing pediatric athletes with medial epicondyle fractures treated operatively and non-operatively that reported functional and radiographic outcomes were compiled. We identified 6 studies with a total of 99 patients (52 treated operatively and 47 treated non-operatively). We found a significantly higher union rate with operative treatment (100%) compared to non-operative treatment (76%, p = 0.0025), with equivalent return to sport time and rate. Non-operative treatment had a lower complication and repeat surgery rates (p = 0.009). This study demonstrates lower complication rates and equivalent functional outcomes between operative and non-operatively treated medial epicondyle fractures in athletes. Non-operative treatment is a valid option in these patients. (Journal of Surgical Orthopaedic Advances 32(1):009-013, 2023).


Asunto(s)
Lesiones de Codo , Fracturas del Húmero , Humanos , Niño , Fracturas del Húmero/cirugía , Resultado del Tratamiento , Fijación Interna de Fracturas , Atletas
10.
J Neurosci ; 41(13): 2980-2989, 2021 03 31.
Artículo en Inglés | MEDLINE | ID: mdl-33563728

RESUMEN

The idea that when we use a tool we incorporate it into the neural representation of our body (embodiment) has been a major inspiration for philosophy, science, and engineering. While theoretically appealing, there is little direct evidence for tool embodiment at the neural level. Using functional magnetic resonance imaging (fMRI) in male and female human subjects, we investigated whether expert tool users (London litter pickers: n = 7) represent their expert tool more like a hand (neural embodiment) or less like a hand (neural differentiation), as compared with a group of tool novices (n = 12). During fMRI scans, participants viewed first-person videos depicting grasps performed by either a hand, litter picker, or a non-expert grasping tool. Using representational similarity analysis (RSA), differences in the representational structure of hands and tools were measured within occipitotemporal cortex (OTC). Contrary to the neural embodiment theory, we find that the experts group represent their own tool less like a hand (not more) relative to novices. Using a case-study approach, we further replicated this effect, independently, in five of the seven individual expert litter pickers, as compared with the novices. An exploratory analysis in left parietal cortex, a region implicated in visuomotor representations of hands and tools, also indicated that experts do not visually represent their tool more similar to hands, compared with novices. Together, our findings suggest that extensive tool use leads to an increased neural differentiation between visual representations of hands and tools. This evidence provides an important alternative framework to the prominent tool embodiment theory.SIGNIFICANCE STATEMENT It is commonly thought that tool use leads to the assimilation of the tool into the neural representation of the body, a process referred to as embodiment. Here, we demonstrate that expert tool users (London litter pickers) neurally represent their own tool less like a hand (not more), compared with novices. Our findings advance our current understanding for how experience shapes functional organization in high-order visual cortex. Further, this evidence provides an alternative framework to the prominent tool embodiment theory, suggesting instead that experience with tools leads to more distinct, separable hand and tool representations.


Asunto(s)
Encéfalo/fisiología , Mano/fisiología , Imagen por Resonancia Magnética/métodos , Destreza Motora/fisiología , Estimulación Luminosa/métodos , Desempeño Psicomotor/fisiología , Adulto , Encéfalo/diagnóstico por imagen , Mapeo Encefálico/métodos , Femenino , Fuerza de la Mano/fisiología , Humanos , Masculino , Persona de Mediana Edad
11.
Proteins ; 90(1): 186-199, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34369028

RESUMEN

To create bacterial transcription "circuits" for biotechnology, one approach is to recombine natural transcription factors, promoters, and operators. Additional novel functions can be engineered from existing transcription factors such as the E. coli AraC transcriptional activator, for which binding to DNA is modulated by binding L-arabinose. Here, we engineered chimeric AraC/XylS transcription activators that recognized ara DNA binding sites and responded to varied effector ligands. The first step, identifying domain boundaries in the natural homologs, was challenging because (i) no full-length, dimeric structures were available and (ii) extremely low sequence identities (≤10%) among homologs precluded traditional assemblies of sequence alignments. Thus, to identify domains, we built and aligned structural models of the natural proteins. The designed chimeric activators were assessed for function, which was then further improved by random mutagenesis. Several mutational variants were identified for an XylS•AraC chimera that responded to benzoate; two enhanced activation to near that of wild-type AraC. For an RhaR•AraC chimera, a variant with five additional substitutions enabled transcriptional activation in response to rhamnose. These five changes were dispersed across the protein structure, and combinatorial experiments testing subsets of substitutions showed significant non-additivity. Combined, the structure modeling and epistasis suggest that the common AraC/XylS structural scaffold is highly interconnected, with complex intra-protein and inter-domain communication pathways enabling allosteric regulation. At the same time, the observed epistasis and the low sequence identities of the natural homologs suggest that the structural scaffold and function of transcriptional regulation are nevertheless highly accommodating of amino acid changes.


Asunto(s)
Factor de Transcripción de AraC , Proteínas Bacterianas , Proteínas de Unión al ADN , Proteínas de Escherichia coli , Transactivadores , Regulación Alostérica , Aminoácidos/química , Aminoácidos/genética , Factor de Transcripción de AraC/química , Factor de Transcripción de AraC/genética , Factor de Transcripción de AraC/metabolismo , Proteínas Bacterianas/química , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Proteínas de Unión al ADN/química , Proteínas de Unión al ADN/genética , Proteínas de Unión al ADN/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Regulación Bacteriana de la Expresión Génica/genética , Mutación/genética , Proteínas Recombinantes de Fusión/química , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Transactivadores/química , Transactivadores/genética , Transactivadores/metabolismo
12.
J Hepatol ; 76(4): 921-933, 2022 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-34953958

RESUMEN

BACKGROUND & AIMS: Biliary disease is associated with a proliferative/fibrogenic ductular reaction (DR). p300 is an epigenetic regulator that acetylates lysine 27 on histone 3 (H3K27ac) and is activated during fibrosis. Long non-coding RNAs (lncRNAs) are aberrantly expressed in cholangiopathies, but little is known about how they recruit epigenetic complexes and regulate DR. We investigated epigenetic complexes, including transcription factors (TFs) and lncRNAs, contributing to p300-mediated transcription during fibrosis. METHODS: We evaluated p300 in vivo using tamoxifen-inducible, cholangiocyte-selective, p300 knockout (KO) coupled with bile duct ligation (BDL) and Mdr KO mice treated with SGC-CBP30. Primary cholangiocytes and liver tissue were analyzed for expression of Acta2-as1 lncRNA by qPCR and RNA in situ hybridization. In vitro, we performed RNA-sequencing in human cholangiocytes with a p300 inhibitor. Cholangiocytes were exposed to lipopolysaccharide (LPS) as an injury model. We confirmed formation of a p300/ELK1 complex by immunoprecipitation (IP). RNA IP was used to examine interactions between ACTA2-AS1 and p300. Chromatin IP assays were used to evaluate p300/ELK1 occupancy and p300-mediated H3K27ac. Organoids were generated from ACTA2-AS1-depleted cholangiocytes. RESULTS: BDL-induced DR and fibrosis were reduced in Krt19-CreERT/p300fl/fl mice. Similarly, Mdr KO mice were protected from DR and fibrosis after SGC-CBP30 treatment. In vitro, depletion of ACTA2-AS1 reduced expression of proliferative/fibrogenic markers, reduced LPS-induced cholangiocyte proliferation, and impaired organoid formation. ACTA2-AS1 regulated transcription by facilitating p300/ELK1 binding to the PDGFB promoter after LPS exposure. Correspondingly, LPS-induced H3K27ac was mediated by p300/ELK1 and was reduced in ACTA2-AS1-depleted cholangiocytes. CONCLUSION: Cholangiocyte-selective p300 KO or p300 inhibition attenuate DR/fibrosis in mice. ACTA2-AS1 influences recruitment of p300/ELK1 to specific promoters to drive H3K27ac and epigenetic activation of proliferative/fibrogenic genes. This suggests that cooperation between epigenetic co-activators and lncRNAs facilitates DR/fibrosis in biliary diseases. LAY SUMMARY: We identified a three-part complex containing an RNA molecule, a transcription factor, and an epigenetic enzyme. The complex is active in injured bile duct cells and contributes to activation of genes involved in proliferation and fibrosis.


Asunto(s)
ARN Largo no Codificante , Animales , Conductos Biliares/patología , Proliferación Celular , Fibrosis , Lipopolisacáridos , Hígado/patología , Ratones , Ratones Noqueados , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo
13.
Antimicrob Agents Chemother ; 66(6): e0053622, 2022 06 21.
Artículo en Inglés | MEDLINE | ID: mdl-35638855

RESUMEN

Mycobacteroides abscessus (Mab) is an emerging environmental microbe that causes chronic lung disease in patients with compromised lung function such as cystic fibrosis and bronchiectasis. It is intrinsically resistant to most antibiotics, therefore there are only few antibiotics that can be repurposed to treat Mab disease. Although current recommendations require daily intake of multiple antibiotics for more than a year, cure rate is low and often associated with significant adverse events. Here, we describe in vivo efficacy of T405, a recently discovered ß-lactam antibiotic of the penem subclass, in a mouse model of pulmonary Mab infection. Imipenem, one of the standard-of-care drugs to treat Mab disease, and also a ß-lactam antibiotic from a chemical class similar to T405, was included as a comparator. Probenecid was included with both T405 and imipenem to reduce the rate of their renal clearance. T405 exhibited bactericidal activity against Mab from the onset of treatment and reduced Mab lung burden at a rate similar to that exhibited by imipenem. The MIC of T405 against Mab was unaltered after 4 weeks of exposure to T405 in the lungs of mice. Using an in vitro assay, we also demonstrate that T405 in combination with imipenem, cefditoren or avibactam exhibits synergism against Mab. Additionally, we describe a scheme for synthesis and purification of T405 on an industrial scale. These attributes make T405 a promising candidate for further preclinical assessment to treat Mab disease.


Asunto(s)
Imipenem , Infecciones por Mycobacterium no Tuberculosas , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Cefalosporinas , Humanos , Imipenem/farmacología , Imipenem/uso terapéutico , Meropenem/uso terapéutico , Ratones , Pruebas de Sensibilidad Microbiana , Infecciones por Mycobacterium no Tuberculosas/tratamiento farmacológico , beta-Lactamas/uso terapéutico
14.
Artículo en Inglés | MEDLINE | ID: mdl-35609964

RESUMEN

Phantom limb pain (PLP) impacts the majority of individuals who undergo limb amputation. The PLP experience is highly heterogenous in its quality, intensity, frequency and severity. This heterogeneity, combined with the low prevalence of amputation in the general population, has made it difficult to accumulate reliable data on PLP. Consequently, we lack consensus on PLP mechanisms, as well as effective treatment options. However, the wealth of new PLP research, over the past decade, provides a unique opportunity to re-evaluate some of the core assumptions underlying what we know about PLP and the rationale behind PLP treatments. The goal of this review is to help generate consensus in the field on how best to research PLP, from phenomenology to treatment. We highlight conceptual and methodological challenges in studying PLP, which have hindered progress on the topic and spawned disagreement in the field, and offer potential solutions to overcome these challenges. Our hope is that a constructive evaluation of the foundational knowledge underlying PLP research practices will enable more informed decisions when testing the efficacy of existing interventions and will guide the development of the next generation of PLP treatments.

15.
J Neurooncol ; 159(2): 301-308, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-35731362

RESUMEN

PURPOSE: The role of white blood cells (WBC) in the pediatric central nervous system (CNS) tumor microenvironment is incompletely defined. We hypothesized that the WBC profile in cerebrospinal fluid (CSF) correlates with the presence of tumor cells and prognosis in pediatric CNS tumors, as well as other patient and disease characteristics, and differs by tumor type, thus giving insight into the tumor immune response. METHODS: We conducted a retrospective analysis of CSF WBC profiles at CNS tumor diagnosis in 269 patients at our institution. We examined total nucleated cell count, absolute counts, and percentages by WBC subtype. We compared CSF WBC values by tumor cell presence, patient vital status, tumor location, and the most common tumor types. RESULTS: Patients who died of their tumor had a lower CSF lymphocyte percentage and a higher absolute monocyte count in CSF at diagnosis. The presence of tumor cells in CSF was associated with fewer lymphocytes and monocytes. Ventricular tumors had higher CSF lymphocyte, monocyte, macrophage, and total nucleated cell counts than extraventricular tumors. Germ cell tumors, low-grade glioma, high-grade glioma, and ependymoma had lower macrophage counts or percentages compared to other tumor types. CONCLUSIONS: WBC profile in CSF at pediatric CNS tumor diagnosis correlates with patient prognosis and presence of metastatic cells, along with tumor type and other tumor characteristics like relationship to the ventricles. Prospective CSF profiling and study may be useful to future immunotherapy and other pediatric CNS tumor clinical trials.


Asunto(s)
Neoplasias Encefálicas , Neoplasias del Sistema Nervioso Central , Ependimoma , Líquido Cefalorraquídeo , Niño , Humanos , Leucocitos , Estudios Prospectivos , Estudios Retrospectivos , Microambiente Tumoral
16.
BMC Neurol ; 22(1): 474, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36510237

RESUMEN

BACKGROUND: Depressive symptoms are common in patients with Parkinson's disease and depression is a significant predictor of functional impairment, reduced quality of life and general well-being in Parkinson's disease. Despite the high prevalence of depression, evidence on the effectiveness and tolerability of antidepressants in this population is limited. The primary aim of this trial is to establish the clinical and cost effectiveness of escitalopram and nortriptyline for the treatment of depression in Parkinson's disease. METHODS: This is a multi-centre, double-blind, randomised placebo-controlled trial in 408 people with Parkinson's disease with subsyndromal depression, major depressive disorder or persistent depressive disorder and a Beck Depression Inventory-II (BDI-II) score of 14 or above. Participants will be randomised into one of three groups, receiving either escitalopram, nortriptyline or placebo for 12 months. Trial participation is face-to-face, hybrid or remote. The primary outcome measure is the BDI-II score following 8 weeks of treatment. Secondary outcomes will be collected at baseline, 8, 26 and 52 weeks and following withdrawal, including severity of anxiety and depression scores as well as Parkinson's disease motor severity, and ratings of non-motor symptoms, cognitive function, health-related quality of life, levodopa-equivalence dose, changes in medication, overall clinical effectiveness, capability, health and social care resource use, carer health-related quality of life, adverse effects and number of dropouts. DISCUSSION: This trial aims to determine the effectiveness of escitalopram and nortriptyline for reducing depressive symptoms in Parkinson's disease over 8 weeks, to provide information on the effect of these medications on anxiety and other non-motor symptoms in PD and on impact on patients and caregivers, and to examine their effect on change in motor severity. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03652870 Date of registration - 29th August 2018.


Asunto(s)
Trastorno Depresivo Mayor , Enfermedad de Parkinson , Humanos , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/tratamiento farmacológico , Trastorno Depresivo Mayor/tratamiento farmacológico , Calidad de Vida , Escitalopram , Antidepresivos/uso terapéutico , Nortriptilina/uso terapéutico , Resultado del Tratamiento , Método Doble Ciego , Ensayos Clínicos Controlados Aleatorios como Asunto , Estudios Multicéntricos como Asunto
17.
Int J Mol Sci ; 23(6)2022 Mar 12.
Artículo en Inglés | MEDLINE | ID: mdl-35328501

RESUMEN

Based on the rapid increase in incidence of inflammatory bowel disease (IBD), the identification of susceptibility genes and cell populations contributing to this condition is essential. Previous studies suggested multiple genes associated with the susceptibility of IBD; however, due to the analysis of whole-tissue samples, the contribution of individual cell populations remains widely unresolved. Single-cell RNA sequencing (scRNA-seq) provides the opportunity to identify underlying cellular populations. We determined the enrichment of Crohn's disease (CD)-induced genes in a publicly available Crohn's disease scRNA-seq dataset and detected the strongest induction of these genes in innate lymphoid cells (ILC1), highly activated T cells and dendritic cells, pericytes and activated fibroblasts, as well as epithelial cells. Notably, these genes were highly enriched in IBD-associated neoplasia, as well as sporadic colorectal cancer (CRC). Indeed, the same six cell populations displayed an upregulation of CD-induced genes in a CRC scRNA-seq dataset. Finally, after integrating and harmonizing the CD and CRC scRNA-seq data, we demonstrated that these six cell types display a gradual increase in gene expression levels from a healthy state to an inflammatory and tumorous state. Together, we identified cell populations that specifically upregulate CD-induced genes in CD and CRC patients and could, therefore, contribute to inflammation-associated tumor development.


Asunto(s)
Colitis Ulcerosa , Neoplasias Colorrectales , Enfermedad de Crohn , Enfermedades Inflamatorias del Intestino , Colitis Ulcerosa/patología , Neoplasias Colorrectales/patología , Enfermedad de Crohn/patología , Humanos , Inmunidad Innata , Inflamación/complicaciones , Inflamación/genética , Enfermedades Inflamatorias del Intestino/patología , Linfocitos/patología
18.
Genet Med ; 23(3): 534-542, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33110267

RESUMEN

PURPOSE: Heterozygous pathogenic variants in various FOXP genes cause specific developmental disorders. The phenotype associated with heterozygous variants in FOXP4 has not been previously described. METHODS: We assembled a cohort of eight individuals with heterozygous and mostly de novo variants in FOXP4: seven individuals with six different missense variants and one individual with a frameshift variant. We collected clinical data to delineate the phenotypic spectrum, and used in silico analyses and functional cell-based assays to assess pathogenicity of the variants. RESULTS: We collected clinical data for six individuals: five individuals with a missense variant in the forkhead box DNA-binding domain of FOXP4, and one individual with a truncating variant. Overlapping features included speech and language delays, growth abnormalities, congenital diaphragmatic hernia, cervical spine abnormalities, and ptosis. Luciferase assays showed loss-of-function effects for all these variants, and aberrant subcellular localization patterns were seen in a subset. The remaining two missense variants were located outside the functional domains of FOXP4, and showed transcriptional repressor capacities and localization patterns similar to the wild-type protein. CONCLUSION: Collectively, our findings show that heterozygous loss-of-function variants in FOXP4 are associated with an autosomal dominant neurodevelopmental disorder with speech/language delays, growth defects, and variable congenital abnormalities.


Asunto(s)
Anomalías Múltiples , Discapacidad Intelectual , Trastornos del Desarrollo del Lenguaje , Niño , Discapacidades del Desarrollo/genética , Factores de Transcripción Forkhead/genética , Heterocigoto , Humanos , Trastornos del Desarrollo del Lenguaje/genética , Mutación Missense , Habla
19.
J Cardiovasc Electrophysiol ; 32(4): 941-948, 2021 04.
Artículo en Inglés | MEDLINE | ID: mdl-33527562

RESUMEN

Catheter ablation is an established effective approach for the treatment of atrial fibrillation (AF) in patients with heart failure, however, the role of cryoablation in this setting is unclear. Procedural success and left ventricular systolic dysfunction (LVEF) improvement in patients with LVEF ≤ 45% undergoing index catheter ablation with cryoablation were evaluated. Freedom from AF recurrence was seen in 43% rising to 59% following repeat procedure. There were significant improvements in LVEF and functional status at long-term follow-up. Results were comparable to a contemporaneous cohort of heart failure patients undergoing index ablation with radiofrequency ablation. Cryoablation is an effective first-line AF ablation approach in the setting of heart failure.


Asunto(s)
Fibrilación Atrial , Ablación por Catéter , Criocirugía , Insuficiencia Cardíaca Sistólica , Venas Pulmonares , Fibrilación Atrial/diagnóstico , Fibrilación Atrial/cirugía , Ablación por Catéter/efectos adversos , Criocirugía/efectos adversos , Humanos , Venas Pulmonares/cirugía , Recurrencia , Resultado del Tratamiento
20.
Br J Surg ; 108(7): 797-803, 2021 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-34136900

RESUMEN

BACKGROUND: Recovery of gastrointestinal (GI) function is often delayed after colorectal surgery. Enhanced recovery protocols (ERPs) recommend routine laxative use, but evidence of benefit is unclear. This study aimed to investigate whether the addition of multimodal laxatives to an ERP improves return of GI function in patients undergoing colorectal surgery. METHODS: This was a single-centre, parallel, open-label RCT. All adult patients undergoing elective colorectal resection or having stoma formation or reversal at the Royal Adelaide Hospital between August 2018 and May 2020 were recruited into the study. The STIMULAX group received oral Coloxyl® with senna and macrogol, with a sodium phosphate enema in addition for right-sided operations. The control group received standard ERP postoperative care. The primary outcome was GI-2, a validated composite measure defined as the interval from surgery until first passage of stool and tolerance of solid intake for 24 h in the absence of vomiting. Secondary outcomes were the incidence of prolonged postoperative ileus (POI), duration of hospital stay, and postoperative complications. The analysis was performed on an intention-to-treat basis. RESULTS: Of a total of 170 participants, 85 were randomized to each group. Median GI-2 was 1 day shorter in the STIMULAX compared with the control group (median 2 (i.q.r. 1.5-4) versus 3 (2-5.5) days; 95 per cent c.i. -1 to 0 days; P = 0.029). The incidence of prolonged POI was lower in the STIMULAX group (22 versus 38 per cent; relative risk reduction 42 per cent; P = 0.030). There was no difference in duration of hospital day or 30-day postoperative complications (including anastomotic leak) between the STIMULAX and control groups. CONCLUSION: Routine postoperative use of multimodal laxatives after elective colorectal surgery results in earlier recovery of gastrointestinal function and reduces the incidence of prolonged POI. Registration number: ACTRN12618001261202 (www.anzctr.org.au).


Asunto(s)
Colectomía/efectos adversos , Procedimientos Quirúrgicos Electivos/efectos adversos , Tracto Gastrointestinal/fisiopatología , Laxativos/uso terapéutico , Cuidados Posoperatorios/métodos , Complicaciones Posoperatorias/terapia , Recuperación de la Función , Anciano , Femenino , Tracto Gastrointestinal/efectos de los fármacos , Tracto Gastrointestinal/cirugía , Humanos , Tiempo de Internación/tendencias , Masculino , Persona de Mediana Edad
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