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1.
Cell ; 165(3): 606-19, 2016 Apr 21.
Artículo en Inglés | MEDLINE | ID: mdl-27104978

RESUMEN

Rbfox proteins control alternative splicing and posttranscriptional regulation in mammalian brain and are implicated in neurological disease. These proteins recognize the RNA sequence (U)GCAUG, but their structures and diverse roles imply a variety of protein-protein interactions. We find that nuclear Rbfox proteins are bound within a large assembly of splicing regulators (LASR), a multimeric complex containing the proteins hnRNP M, hnRNP H, hnRNP C, Matrin3, NF110/NFAR-2, NF45, and DDX5, all approximately equimolar to Rbfox. We show that splicing repression mediated by hnRNP M is stimulated by Rbfox. Virtually all the intron-bound Rbfox is associated with LASR, and hnRNP M motifs are enriched adjacent to Rbfox crosslinking sites in vivo. These findings demonstrate that Rbfox proteins bind RNA with a defined set of cofactors and affect a broader set of exons than previously recognized. The function of this multimeric LASR complex has implications for deciphering the regulatory codes controlling splicing networks.


Asunto(s)
Empalme del ARN , Proteínas de Unión al ARN/metabolismo , Regiones no Traducidas 3' , Animales , Encéfalo/citología , Encéfalo/metabolismo , Núcleo Celular/metabolismo , Exones , Células HEK293 , Humanos , Intrones , Ratones , Complejos Multiproteicos/metabolismo , Precursores del ARN/metabolismo
2.
J Neuroinflammation ; 21(1): 38, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38302975

RESUMEN

BACKGROUND: Herpes simplex virus (HSV) encephalitis (HSE) is a serious and potentially life-threatening disease, affecting both adults and newborns. Progress in understanding the virus and host factors involved in neonatal HSE has been hampered by the limitations of current brain models that do not fully recapitulate the tissue structure and cell composition of the developing human brain in health and disease. Here, we developed a human fetal organotypic brain slice culture (hfOBSC) model and determined its value in mimicking the HSE neuropathology in vitro. METHODS: Cell viability and tissues integrity were determined by lactate dehydrogenase release in supernatant and immunohistological (IHC) analyses. Brain slices were infected with green fluorescent protein (GFP-) expressing HSV-1 and HSV-2. Virus replication and spread were determined by confocal microscopy, PCR and virus culture. Expression of pro-inflammatory cytokines and chemokines were detected by PCR. Cell tropism and HSV-induced neuropathology were determined by IHC analysis. Finally, the in situ data of HSV-infected hfOBSC were compared to the neuropathology detected in human HSE brain sections. RESULTS: Slicing and serum-free culture conditions were optimized to maintain the viability and tissue architecture of ex vivo human fetal brain slices for at least 14 days at 37 °C in a CO2 incubator. The hfOBSC supported productive HSV-1 and HSV-2 infection, involving predominantly infection of neurons and astrocytes, leading to expression of pro-inflammatory cytokines and chemokines. Both viruses induced programmed cell death-especially necroptosis-in infected brain slices at later time points after infection. The virus spread, cell tropism and role of programmed cell death in HSV-induced cell death resembled the neuropathology of HSE. CONCLUSIONS: We developed a novel human brain culture model in which the viability of the major brain-resident cells-including neurons, microglia, astrocytes and oligodendrocytes-and the tissue architecture is maintained for at least 2 weeks in vitro under serum-free culture conditions. The close resemblance of cell tropism, spread and neurovirulence of HSV-1 and HSV-2 in the hfOBSC model with the neuropathological features of human HSE cases underscores its potential to detail the pathophysiology of other neurotropic viruses and as preclinical model to test novel therapeutic interventions.


Asunto(s)
Encefalitis por Herpes Simple , Herpes Simple , Herpesvirus Humano 1 , Recién Nacido , Adulto , Humanos , Astrocitos/patología , Necroptosis , Herpes Simple/patología , Encéfalo/patología , Citocinas , Neuronas/patología , Quimiocinas
3.
Development ; 147(22)2020 11 16.
Artículo en Inglés | MEDLINE | ID: mdl-33060132

RESUMEN

The mammalian cortex is populated by neurons derived from neural progenitors located throughout the embryonic telencephalon. Excitatory neurons are derived from the dorsal telencephalon, whereas inhibitory interneurons are generated in its ventral portion. The transcriptional regulator PRDM16 is expressed by radial glia, neural progenitors present in both regions; however, its mechanisms of action are still not fully understood. It is unclear whether PRDM16 plays a similar role in neurogenesis in both dorsal and ventral progenitor lineages and, if so, whether it regulates common or unique networks of genes. Here, we show that Prdm16 expression in mouse medial ganglionic eminence (MGE) progenitors is required for maintaining their proliferative capacity and for the production of proper numbers of forebrain GABAergic interneurons. PRDM16 binds to cis-regulatory elements and represses the expression of region-specific neuronal differentiation genes, thereby controlling the timing of neuronal maturation. PRDM16 regulates convergent developmental gene expression programs in the cortex and MGE, which utilize both common and region-specific sets of genes to control the proliferative capacity of neural progenitors, ensuring the generation of correct numbers of cortical neurons.


Asunto(s)
Corteza Cerebral/metabolismo , Proteínas de Unión al ADN/metabolismo , Neuronas GABAérgicas/metabolismo , Interneuronas/metabolismo , Células-Madre Neurales/metabolismo , Factores de Transcripción/metabolismo , Animales , Corteza Cerebral/citología , Proteínas de Unión al ADN/genética , Neuronas GABAérgicas/citología , Interneuronas/citología , Ratones , Células-Madre Neurales/citología , Factores de Transcripción/genética
4.
Proc Natl Acad Sci U S A ; 117(8): 4310-4319, 2020 02 25.
Artículo en Inglés | MEDLINE | ID: mdl-32041868

RESUMEN

Immunological synapse formation between cytotoxic T lymphocytes (CTLs) and the target cells they aim to destroy is accompanied by reorientation of the CTL centrosome to a position beneath the synaptic membrane. Centrosome polarization is thought to enhance the potency and specificity of killing by driving lytic granule fusion at the synapse and thereby the release of perforin and granzymes toward the target cell. To test this model, we employed a genetic strategy to delete centrioles, the core structural components of the centrosome. Centriole deletion altered microtubule architecture as expected but surprisingly had no effect on lytic granule polarization and directional secretion. Nevertheless, CTLs lacking centrioles did display substantially reduced killing potential, which was associated with defects in both lytic granule biogenesis and synaptic actin remodeling. These results reveal an unexpected role for the intact centrosome in controlling the capacity but not the specificity of cytotoxic killing.


Asunto(s)
Centriolos/inmunología , Linfocitos T Citotóxicos/inmunología , Animales , Centrosoma/inmunología , Pruebas Inmunológicas de Citotoxicidad , Ratones Endogámicos C57BL , Microtúbulos/genética , Microtúbulos/inmunología , Especificidad de la Especie
5.
Nanotechnology ; 32(40)2021 Jul 13.
Artículo en Inglés | MEDLINE | ID: mdl-34102628

RESUMEN

Owing to many fascinating properties including high thermal and chemical stability, excellent electrical insulation, fire-retardant and antibacterial properties, hexagonal boron nitride (hBN) has emerged as a prominent 2D material for broad applications. However, the production of high quality of hBN by chemical exfoliation from its precursor is still challenging. This paper presents a high-yield (+83%), low-cost and energy-efficient wet chemical exfoliation strategy, which produces few-layers (FL, 3-6 layers) of edge-functionalized (OH) hBN nanosheets with uniform size (486 ± 51 nm). This optimized preparation is established based on a comprehensive investigation on the key exfoliation parameters such as exfoliation temperature, time and amount of the oxidant (potassium permanganate). High quality of FL-hBN was confirmed by various characterization techniques including scanning electron microscopy coupled with energy dispersive X-ray, transmission electron microscopy, Raman, Fourier transform infrared spectroscopy, X-ray diffraction and X-ray photoelectron spectroscopy analyses. The outcome of this study paves a promising pathway to effectively produce hBN through a cost-efficient exfoliation approach, which has a significant impact on industrial applications.

6.
Gastroenterology ; 154(6): 1737-1750, 2018 05.
Artículo en Inglés | MEDLINE | ID: mdl-29360463

RESUMEN

BACKGROUND & AIMS: Clostridium difficile induces intestinal inflammation by releasing toxins A and B. The antimicrobial compound cationic steroid antimicrobial 13 (CSA13) has been developed for treating gastrointestinal infections. The CSA13-Eudragit formulation can be given orally and releases CSA13 in the terminal ileum and colon. We investigated whether this form of CSA13 reduces C difficile infection (CDI) in mice. METHODS: C57BL/6J mice were infected with C difficile on day 0, followed by subcutaneous administration of pure CSA13 or oral administration of CSA13-Eudragit (10 mg/kg/d for 10 days). Some mice were given intraperitoneal vancomycin (50 mg/kg daily) on days 0-4 and relapse was measured after antibiotic withdrawal. The mice were monitored until day 20; colon and fecal samples were collected on day 3 for analysis. Blood samples were collected for flow cytometry analyses. Fecal pellets were collected each day from mice injected with CSA13 and analyzed by high-performance liquid chromatography or 16S sequencing; feces were also homogenized in phosphate-buffered saline and fed to mice with CDI via gavage. RESULTS: CDI of mice caused 60% mortality, significant bodyweight loss, and colonic damage 3 days after infection; these events were prevented by subcutaneous injection of CSA13 or oral administration CSA13-Eudragit. There was reduced relapse of CDI after administration of CSA13 was stopped. Levels of CSA13 in feces from mice given CSA13-Eudragit were significantly higher than those of mice given subcutaneous CSA13. Subcutaneous and oral CSA13 each significantly increased the abundance of Peptostreptococcaceae bacteria and reduced the abundance of C difficile in fecal samples of mice. When feces from mice with CDI and given CSA13 were fed to mice with CDI that had not received CSA13, the recipient mice had significantly increased rates of survival. CSA13 reduced fecal levels of inflammatory metabolites (endocannabinoids) and increased fecal levels of 4 protective metabolites (ie, citrulline, 3-aminoisobutyric acid, retinol, and ursodeoxycholic acid) in mice with CDI. Oral administration of these CSA13-dependent protective metabolites reduced the severity of CDI. CONCLUSIONS: In studies of mice, we found the CSA13-Eudragit formulation to be effective in eradicating CDI by modulating the intestinal microbiota and metabolites.


Asunto(s)
Antibacterianos/administración & dosificación , Clostridioides difficile/efectos de los fármacos , Enterocolitis Seudomembranosa/tratamiento farmacológico , Microbioma Gastrointestinal/efectos de los fármacos , Esteroides/administración & dosificación , Animales , Heces/microbiología , Intestinos/efectos de los fármacos , Intestinos/microbiología , Ratones , Ratones Endogámicos C57BL , Vancomicina/administración & dosificación
7.
Clin Chem ; 65(12): 1572-1580, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31628138

RESUMEN

BACKGROUND: The ratio of ß-amyloid 1-42 (Aß42) to Aß40 in cerebrospinal fluid (CSF) may be useful for evaluating Alzheimer disease (AD), but quantification is limited by factors including preanalytical analyte loss. We developed an LC-MS/MS assay that limits analyte loss. Here we describe the analytical characteristics of the assay and its performance in differentiating patients with AD from non-AD dementia and healthy controls. METHODS: To measure Aß42/Aß40, we used unique proteolytically derived C-terminal peptides as surrogate markers of Aß40 and Aß42, which were analyzed and quantified by LC-MS/MS. The assay was analytically validated and applied to specimens from individuals with clinically diagnosed AD (n = 102), mild cognitive impairment (n = 37), and non-AD dementias (n = 22), as well as from healthy controls (n = 130). Aß42/Aß40 values were compared with APOE genotype inferred from phenotype, also measured by LC-MS/MS. RESULTS: The assay had a reportable range of 100 to 25000 pg/mL, a limit of quantification of 100 pg/mL, recoveries between 93% and 111%, and intraassay and interassay CV <15% for both peptides. An Aß42/Aß40 ratio cutoff of <0.16 had a clinical sensitivity of 78% for distinguishing patients with AD from non-AD dementia (clinical specificity, 91%) and from healthy controls (clinical specificity, 81%). The Aß42/Aß40 ratio decreased significantly (P < 0.001) with increasing dose of APOE4 alleles. CONCLUSIONS: This assay can be used to determine Aß42/Aß40 ratios, which correlate with the presence of AD.


Asunto(s)
Péptidos beta-Amiloides/análisis , Fragmentos de Péptidos/análisis , Espectrometría de Masas en Tándem/métodos , Anciano , Enfermedad de Alzheimer/diagnóstico , Enfermedad de Alzheimer/metabolismo , Péptidos beta-Amiloides/líquido cefalorraquídeo , Biomarcadores/líquido cefalorraquídeo , Cromatografía Liquida/métodos , Disfunción Cognitiva/diagnóstico , Disfunción Cognitiva/metabolismo , Demencia/diagnóstico , Demencia/metabolismo , Femenino , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Masculino , Persona de Mediana Edad , Fragmentos de Péptidos/líquido cefalorraquídeo , Sensibilidad y Especificidad , Proteínas tau/líquido cefalorraquídeo
8.
Glia ; 66(12): 2700-2718, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30277607

RESUMEN

Emerging evidence have posited that dysregulated microglia impair clearance and containment of amyloid-ß (Aß) species in the brain, resulting in aberrant buildup of Aß and onset of Alzheimer's disease (AD). Hematopoietic cell kinase (Hck) is one of the key regulators of phagocytosis among the Src family tyrosine kinases (SFKs) in myeloid cells, and its expression is found to be significantly altered in AD brains. However, the role of Hck signaling in AD pathogenesis is unknown. We employed pharmacological inhibition and genetic ablation of Hck in BV2 microglial cells and J20 mouse model of AD, respectively, to evaluate the impact of Hck deficiency on Aß-stimulated microglial phagocytosis, Aß clearance, and resultant AD-like neuropathology. Our in vitro data reveal that pharmacological inhibition of SFKs/Hck in BV2 cells and genetic ablation of their downstream kinase, spleen tyrosine kinase (Syk), in primary microglia significantly attenuate Aß oligomers-stimulated microglial phagocytosis. Whereas in Hck-deficient J20 mice, we observed exacerbated Aß plaque burden, reduced microglial coverage, containment, and phagocytosis of Aß plaques, and induced iNOS expression in plaque-associated microglial clusters. These multifactorial changes in microglial activities led to attenuated PSD95 levels in hippocampal DG and CA3 regions, but did not alter the postsynaptic dendritic spine morphology at the CA1 region nor cognitive function of the mice. Hck inhibition thus accelerates early stage AD-like neuropathology by dysregulating microglial function and inducing neuroinflammation. Our data implicate that Hck pathway plays a prominent role in regulating microglial neuroprotective function during the early stage of AD development.


Asunto(s)
Enfermedad de Alzheimer/patología , Encéfalo/patología , Regulación de la Expresión Génica/genética , Microglía/enzimología , Proteínas Proto-Oncogénicas c-hck/metabolismo , Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/fisiopatología , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animales , Células CHO , Células Cultivadas , Cricetulus , Modelos Animales de Enfermedad , Antagonistas de Estrógenos/farmacología , Conducta Exploratoria/fisiología , Regulación Enzimológica de la Expresión Génica/efectos de los fármacos , Regulación Enzimológica de la Expresión Génica/genética , Lipopolisacáridos/farmacología , Ratones , Ratones Transgénicos , Microglía/efectos de los fármacos , Microglía/ultraestructura , Fagocitosis/efectos de los fármacos , Fagocitosis/genética , Proteínas Proto-Oncogénicas c-hck/genética , Receptores del Factor de Crecimiento Derivado de Plaquetas/genética , Receptores del Factor de Crecimiento Derivado de Plaquetas/metabolismo , Quinasa Syk/genética , Quinasa Syk/metabolismo , Tamoxifeno/análogos & derivados , Tamoxifeno/farmacología , Transfección
9.
Artículo en Inglés | MEDLINE | ID: mdl-29038278

RESUMEN

Clostridium difficile causes diarrhea and colitis by releasing toxin A and toxin B. In the human colon, both toxins cause intestinal inflammation and stimulate tumor necrosis factor alpha (TNF-α) expression via the activation of NF-κB. It is well established that the macrolide antibiotic fidaxomicin is associated with reduced relapses of C. difficile infection. We showed that fidaxomicin and its primary metabolite OP-1118 significantly inhibited toxin A-mediated intestinal inflammation in mice in vivo and toxin A-induced cell rounding in vitro We aim to determine whether fidaxomicin and OP-1118 possess anti-inflammatory effects against toxin A and toxin B in the human colon and examine the mechanism of this response. We used fresh human colonic explants, NCM460 human colonic epithelial cells, and RAW264.7 mouse macrophages to study the mechanism of the activity of fidaxomicin and OP-1118 against toxin A- and B-mediated cytokine expression and apoptosis. Fidaxomicin and OP-1118 dose-dependently inhibited toxin A- and B-induced TNF-α and interleukin-1ß (IL-1ß) mRNA expression and histological damage in human colonic explants. Fidaxomicin and OP-1118 inhibited toxin A-mediated NF-κB phosphorylation in human and mouse intestinal mucosae. Fidaxomicin and OP-1118 also inhibited toxin A-mediated NF-κB phosphorylation and TNF-α expression in macrophages, which was reversed by the NF-κB activator phorbol myristate acetate (PMA). Fidaxomicin and OP-1118 prevented toxin A- and B-mediated apoptosis in NCM460 cells, which was reversed by the addition of PMA. PMA reversed the cytoprotective effect of fidaxomicin and OP-1118 in toxin-exposed human colonic explants. Fidaxomicin and OP-1118 inhibit C. difficile toxin A- and B-mediated inflammatory responses, NF-κB phosphorylation, and tissue damage in the human colon.


Asunto(s)
Aminoglicósidos/farmacología , Proteínas Bacterianas/metabolismo , Toxinas Bacterianas/metabolismo , Clostridioides difficile/metabolismo , Enterotoxinas/metabolismo , Fidaxomicina/farmacología , FN-kappa B/antagonistas & inhibidores , Animales , Apoptosis/efectos de los fármacos , Línea Celular , Células Epiteliales/microbiología , Células Epiteliales/patología , Humanos , Inflamación/tratamiento farmacológico , Interleucina-1beta/antagonistas & inhibidores , Mucosa Intestinal/microbiología , Mucosa Intestinal/patología , Ratones , Fosforilación/efectos de los fármacos , Células RAW 264.7 , Acetato de Tetradecanoilforbol/farmacología , Factor de Necrosis Tumoral alfa/antagonistas & inhibidores
10.
Am J Pathol ; 186(6): 1623-34, 2016 06.
Artículo en Inglés | MEDLINE | ID: mdl-27106764

RESUMEN

Valosin-containing protein (VCP) mutations cause inclusion body myopathy with Paget disease and frontotemporal dementia. However, the mechanisms by which mutant VCP triggers degeneration remain unknown. Here, we investigated the role of VCP in cellular stress and found that the oxidative stressor arsenite and heat shock-activated stress responses evident by T-intracellular antigen-1-positive granules in C2C12 myoblasts. Granules also contained phosphorylated transactive response DNA-binding protein 43, ubiquitin, microtubule-associated protein 1A/1B light chains 3, and lysosome-associated membrane protein 2. Mutant VCP produced more T-intracellular antigen-1-positive granules than wild-type in the postarsenite exposure period. Similar results were observed for other granule components, indicating that mutant VCP delayed clearance of stress granules. Furthermore, stress granule resolution was impaired on differentiated C2C12 cells expressing mutant VCP. To address whether mutant VCP triggers dysregulation of the stress granule pathway in vivo, we analyzed skeletal muscle of aged VCPR155H-knockin mice. We found significant increments in oxidated proteins but observed the stress granule markers RasGAP SH3-binding protein and phosphorylated eukaryotic translation initiation factor 2α unchanged. The mixed results indicate that mutant VCP together with aging lead to higher oxidative stress in skeletal muscle but were insufficient to disrupt the stress granule pathway. Our findings support that deficiencies in recovery from stressors may result in attenuated tolerance to stress that could trigger muscle degeneration.


Asunto(s)
Adenosina Trifosfatasas/genética , Proteínas de Ciclo Celular/genética , Demencia Frontotemporal/patología , Distrofia Muscular de Cinturas/patología , Mioblastos/patología , Miositis por Cuerpos de Inclusión/patología , Osteítis Deformante/patología , Estrés Oxidativo/fisiología , Animales , Línea Celular , Modelos Animales de Enfermedad , Técnica del Anticuerpo Fluorescente , Demencia Frontotemporal/genética , Humanos , Immunoblotting , Inmunohistoquímica , Ratones , Distrofia Muscular de Cinturas/genética , Mioblastos/metabolismo , Miositis por Cuerpos de Inclusión/genética , Osteítis Deformante/genética , Transfección , Proteína que Contiene Valosina
11.
BMC Gastroenterol ; 17(1): 63, 2017 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-28494754

RESUMEN

BACKGROUND: Cathelicidin (LL-37) is an antimicrobial peptide known to be associated with various autoimmune diseases. We attempt to determine if cathelicidin can accurately reflect IBD disease activity. We hypothesize that serum cathelicidin correlates with mucosal disease activity, stricture, and clinical prognosis of IBD patients. METHODS: Serum samples were collected from two separate cohorts of patients at the University of California, Los Angeles. Cohort 1 consisted of 50 control, 23 UC, and 28 CD patients. Cohort 2 consisted of 20 control, 57 UC, and 67 CD patients. LL-37 levels were determined by ELISA. Data from both cohorts were combined for calculation of accuracies in indicating mucosal disease activity, relative risks of stricture, and odds ratios of predicting disease development. RESULTS: Serum cathelicidin levels were inversely correlated with Partial Mayo Scores of UC patients and Harvey-Bradshaw Indices of CD patients. Among IBD patients with moderate or severe initial disease activity, the patients with high initial LL-37 levels had significantly better recovery than the patients with low initial LL-37 levels after 6-18 months, suggesting that high LL-37 levels correlate with good prognosis. Co-evaluation of LL-37 and CRP levels was more accurate than CRP alone or LL-37 alone in the correlation with Mayo Endoscopic Score of UC patients. Low LL-37 levels indicated a significantly elevated risk of intestinal stricture in CD patients. CONCLUSION: Co-evaluation of LL-37 and CRP can indicate mucosal disease activity in UC patients. LL-37 can predict future clinical activity in IBD patients and indicate risk of intestinal stricture in CD patients.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/sangre , Enfermedades Inflamatorias del Intestino/sangre , Enfermedades Inflamatorias del Intestino/complicaciones , Intestinos/patología , Adulto , Anciano , Proteína C-Reactiva/metabolismo , Colitis Ulcerosa/sangre , Colitis Ulcerosa/complicaciones , Colitis Ulcerosa/patología , Constricción Patológica/etiología , Enfermedad de Crohn/sangre , Enfermedad de Crohn/complicaciones , Enfermedad de Crohn/patología , Femenino , Humanos , Enfermedades Inflamatorias del Intestino/patología , Mucosa Intestinal/patología , Masculino , Persona de Mediana Edad , Pronóstico , Factores de Riesgo , Catelicidinas
12.
Am J Physiol Gastrointest Liver Physiol ; 311(4): G610-G623, 2016 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-27514478

RESUMEN

C. difficile infection (CDI) is a common debilitating nosocomial infection associated with high mortality. Several CDI outbreaks have been attributed to ribotypes 027, 017, and 078. Clinical and experimental evidence indicates that the nonpathogenic yeast Saccharomyces boulardii CNCM I-745 (S.b) is effective for the prevention of CDI. However, there is no current evidence suggesting this probiotic can protect from CDI caused by outbreak-associated strains. We used established hamster models infected with outbreak-associated C. difficile strains to determine whether oral administration of live or heat-inactivated S.b can prevent cecal tissue damage and inflammation. Hamsters infected with C. difficile strain VPI10463 (ribotype 087) and outbreak-associated strains ribotype 017, 027, and 078 developed severe cecal inflammation with mucosal damage, neutrophil infiltration, edema, increased NF-κB phosphorylation, and increased proinflammatory cytokine TNFα protein expression. Oral gavage of live, but not heated, S.b starting 5 days before C. difficile infection significantly reduced cecal tissue damage, NF-κB phosphorylation, and TNFα protein expression caused by infection with all strains. Moreover, S.b-conditioned medium reduced cell rounding caused by filtered supernatants from all C. difficile strains. S.b-conditioned medium also inhibited toxin A- and B-mediated actin cytoskeleton disruption. S.b is effective in preventing C. difficile infection by outbreak-associated via inhibition of the cytotoxic effects of C. difficile toxins.


Asunto(s)
Ciego/microbiología , Infecciones por Clostridium/prevención & control , Inflamación/microbiología , Probióticos/uso terapéutico , Saccharomyces boulardii , Animales , Ciego/metabolismo , Ciego/patología , Clostridioides difficile , Infecciones por Clostridium/microbiología , Cricetinae , Inflamación/metabolismo , Inflamación/patología , FN-kappa B/metabolismo , Fosforilación , Factor de Necrosis Tumoral alfa/metabolismo
13.
Nucleic Acids Res ; 42(3): 1772-83, 2014 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-24217910

RESUMEN

Mouse embryo fibroblasts (MEFs) are convenient sources for biochemical studies when cell number in mouse embryos is limiting. To derive the imprinting signature of MEFs and potentially detect novel imprinted genes we performed strand- and allele-specific RNA deep sequencing. We used sequenom allelotyping in embryo and adult organs to verify parental allele-specific expression. Thirty-two known ubiquitously imprinted genes displayed correct parental allele-specific transcripts in MEFs. Our analysis did not reveal any novel imprinted genes, but detected extended parental allele-specific transcripts in several known imprinted domains: maternal allele-specific transcripts downstream of Grb10 and downstream of Meg3, Rtl1as and Rian in the Dlk1-Dio3 cluster, an imprinted domain implicated in development and pluripotency. We detected paternal allele-specific transcripts downstream of Nespas, Peg3, Peg12 and Snurf/Snrpn. These imprinted transcript extensions were not unique to MEFs, but were also present in other somatic cells. The 5' end points of the imprinted transcript extensions did not carry opposing chromatin marks or parental allele-specific DNA methylation, suggesting that their parental allele-specific transcription is under the control of the extended imprinted genes. Based on the imprinting signature of MEFs, these cells provide valid models for understanding the biochemical aspects of genomic imprinting.


Asunto(s)
Impresión Genómica , Alelos , Animales , Células Cultivadas , Cruzamientos Genéticos , Embrión de Mamíferos/citología , Fibroblastos/metabolismo , Secuenciación de Nucleótidos de Alto Rendimiento , Ratones , Análisis de Secuencia de ARN , Transcripción Genética
14.
Breast ; 75: 103720, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38564975

RESUMEN

INTRODUCTION: Atypical or B3 lesions comprise a heterogeneous group of uncertain malignant potential. B3 lesions diagnosed on core biopsy are usually recommended for diagnostic open biopsy. Identifying factors which could allow conservative management of B3 lesions would be helpful in avoiding unnecessary surgery. The aim of this study was to identify the upgrade rate to malignancy for B3 core biopsy lesions and to compare characteristics of lesions which were malignant and benign at excision. METHOD: This retrospective study used data from BreastScreen New South Wales (NSW), Australia, of women who were diagnosed with B3 lesions on needle biopsy from 2011 to 2019. RESULTS: During the study period, 1927 B3 lesions were included. The upgrade rate to malignancy was 26.4%. Of the malignant lesions on excision, 29.6% were invasive and 69.2% were in situ. The rates of upgrade to invasive cancer and DCIS varied substantially with the core biopsy lesion type. Lesions with atypia on core biopsy had significantly higher upgrade rates to malignancy at 34.7% compared to 13.6% for lesions without atypia (p < 0.0001). Lesions with malignant pathology were significantly larger than those with benign pathology (difference = 5.1 mm (95% CI 2.7-7.5 mm), p < 0.001). CONCLUSIONS: The overall upgrade rate of B3 lesions to malignancy was 26.4%. The majority of the lesions were upgraded to DCIS instead of invasive cancer. Upgrade rates varied by lesion type. Lesions with atypia had significantly higher upgrade rates to cancer compared to lesions without atypia. Malignant lesions were significantly larger than benign lesions.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Estudios Retrospectivos , Nueva Gales del Sur/epidemiología , Persona de Mediana Edad , Neoplasias de la Mama/patología , Biopsia con Aguja Gruesa/estadística & datos numéricos , Adulto , Anciano , Carcinoma Intraductal no Infiltrante/patología , Mama/patología
15.
Radiol Cardiothorac Imaging ; 6(3): e230246, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38934769

RESUMEN

Purpose To investigate the ability of kilovolt-independent (hereafter, kV-independent) and tin filter spectral shaping to accurately quantify the coronary artery calcium score (CACS) and radiation dose reductions compared with the standard 120-kV CT protocol. Materials and Methods This prospective, blinded reader study included 201 participants (mean age, 60 years ± 9.8 [SD]; 119 female, 82 male) who underwent standard 120-kV CT and additional kV-independent and tin filter research CT scans from October 2020 to July 2021. Scans were reconstructed using a Qr36f kernel for standard scans and an Sa36f kernel for research scans simulating artificial 120-kV images. CACS, risk categorization, and radiation doses were compared by analyzing data with analysis of variance, Kruskal-Wallis test, Mann-Whitney test, Bland-Altman analysis, Pearson correlations, and κ analysis for agreement. Results There was no evidence of differences in CACS across standard 120-kV, kV-independent, and tin filter scans, with median CACS values of 1 (IQR, 0-48), 0.6 (IQR, 0-58), and 0 (IQR, 0-51), respectively (P = .85). Compared with standard 120-kV scans, kV-independent and tin filter scans showed excellent correlation in CACS values (r = 0.993 and r = 0.999, respectively), with high agreement in CACS risk categorization (κ = 0.95 and κ = 0.93, respectively). Standard 120-kV scans had a mean radiation dose of 2.09 mSv ± 0.84, while kV-independent and tin filter scans reduced it to 1.21 mSv ± 0.85 and 0.26 mSv ± 0.11, cutting doses by 42% and 87%, respectively (P < .001). Conclusion The kV-independent and tin filter research CT acquisition techniques showed excellent agreement and high accuracy in CACS estimation compared with standard 120-kV scans, with large reductions in radiation dose. Keywords: CT, Cardiac, Coronary Arteries, Radiation Safety, Coronary Artery Calcium Score, Radiation Dose Reduction, Low-Dose CT Scan, Tin Filter, kV-Independent Supplemental material is available for this article. © RSNA, 2024.


Asunto(s)
Enfermedad de la Arteria Coronaria , Vasos Coronarios , Dosis de Radiación , Humanos , Persona de Mediana Edad , Femenino , Masculino , Estudios Prospectivos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Vasos Coronarios/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Calcificación Vascular/diagnóstico por imagen , Estaño/química , Anciano , Angiografía Coronaria/métodos , Reproducibilidad de los Resultados
16.
Development ; 137(1): 5-13, 2010 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-20023155

RESUMEN

Cis-regulatory modules are non-protein-coding regions of DNA essential for the control of gene expression. One class of regulatory modules is embryonic enhancers, which drive gene expression during development as a result of transcription factor protein binding at the enhancer sequences. Recent comparative studies have begun to investigate the evolution of the sequence architecture within enhancers. These analyses are illuminating the way that developmental biologists think about enhancers by revealing their molecular mechanism of function.


Asunto(s)
Drosophila melanogaster/crecimiento & desarrollo , Drosophila melanogaster/genética , Elementos de Facilitación Genéticos/genética , Evolución Molecular , Secuencias Reguladoras de Ácidos Nucleicos/genética , Animales , Modelos Biológicos
17.
Infect Dis Ther ; 12(2): 677-685, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36707466

RESUMEN

INTRODUCTION: Respiratory syncytial virus (RSV) is a leading cause of lower respiratory tract infection (LRTI)-related hospitalizations in older adults. Without RSV-specific treatment for adults, testing is uncommon, leading to potential underestimation of RSV incidence in real-world data studies. This study aimed to quantify the frequency of RSV testing during LRTI-related hospitalizations of older adults to inform interpretation of incidence estimates. METHODS: Administrative and billing data for hospitalizations of adults aged ≥ 65 years with a primary or secondary diagnosis of LRTI during the 2016-2019 RSV seasons (October-April) were extracted from the US all-payer Premier Healthcare Database (PHD). Billing codes identified RSV tests administered during eligible hospitalizations. The proportion of LRTI-related hospitalizations with a billed RSV test was calculated for each hospital in PHD, and summarized descriptively by hospital bed size, teaching status, and population served. RESULTS: Most of the 937 study hospitals performed RSV testing infrequently during LRTI hospitalization; median percentage of LRTI hospitalizations with RSV testing was 4.3%, and 78.4% of hospitals performed RSV testing in less than 25% of LRTI-related hospitalizations. RSV testing varied extensively by hospital type. Median percentage tested was significantly higher for hospitals with ≥ 200 beds (9.1%) versus < 200 beds (1.6%), for teaching (11.0%) versus non-teaching (2.5%) hospitals, and in urban (7.4%) versus rural (0.7%) settings. The median percentage of RSV testing increased over time, from 0.8% to 6.3% between the 2016/17 and 2018/19 seasons. CONCLUSION: A small proportion of older adults hospitalized with LRTI are tested for RSV in US hospitals. Large variability occurs across hospital types. Consequently, retrospective database analyses likely result in a substantial underestimation of the true RSV-related hospitalization incidence. RSV incidence studies using real-world data need to assess for RSV testing frequency and adjust their results for under ascertainment associated with limited testing.

18.
Clin Lymphoma Myeloma Leuk ; 23(6): 426-437.e11, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-37061416

RESUMEN

This systematic literature review (SLR) was conducted to better understand the impact of disease progression, line of therapy, and clinical response on health-related quality of life (HRQoL) in patients with multiple myeloma (MM). Multiple databases were searched to identify records relating to HRQoL in adult patients with MM. Titles and abstracts were independently screened by 2 reviewers for inclusion based on pre-defined criteria. Records flagged for inclusion had full texts subsequently screened using the same method. A third round of screening was then conducted to identify studies that assessed the relationship of HRQoL to disease progression, line of therapy, or clinical response. Quality assessment was conducted on utility studies using the National Institute for Health and Care Excellence Quality Assessment Checklist for Health State Utility Values. After all rounds of screening were complete, 44 records (representing 41 studies) were included in the SLR. Thirty records reported data relating HRQoL to disease progression, 5 reported data relating HRQoL to line of therapy, and 19 reported data relating HRQoL to response. Despite a lack of homogeneity and small number of studies, the data show overall that progressive disease and increasing lines of therapy were associated with worsened patient HRQoL and increasing depth of response was associated with improved patient HRQoL. The findings from this SLR support that desirable treatment outcomes such as delayed progression, fewer lines of therapy, and achieving the deepest possible clinical response result in improved HRQoL in patients with MM.


Asunto(s)
Mieloma Múltiple , Humanos , Mieloma Múltiple/tratamiento farmacológico , Calidad de Vida , Resultado del Tratamiento , Progresión de la Enfermedad
19.
J Med Econ ; 26(1): 915-923, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37431294

RESUMEN

OBJECTIVES: To assess and compare health care resource utilization (HCRU) rates of asciminib and bosutinib at the Week 24, Week 48, and Week 96 cutoffs among 3 L + patients with chronic myeloid leukemia in chronic phase (CML-CP) in the randomized ASCEMBL trial. METHODS: Patients in the ASCEMBL trial (Clinicaltrials.gov: NCT03106779) were randomized to receive asciminib 40 mg twice daily (n = 157) or bosutinib 500 mg once daily (n = 76). At each scheduled visit, investigators conducted HCRU assessment on hospitalization, emergency room visit, general practitioner visit, specialist visit and urgent care visit; duration and type of hospitalization for the hospitalized patients; and reasons for HCRU. The number of patients with HCRU, rate of HCRU per patient-year, and length of hospital stay by ward type were compared at Week 24, Week 48, and Week 96 analyses. RESULTS: Lower proportions of patients receiving asciminib versus bosutinib used any resources including hospitalizations, emergency room visits, general practitioner visits, specialist visits, and urgent care visits (23.6% versus 36.8%, 26.1% versus 39.5%, and 28.6% versus 42.6% at Week 24, Week 48, and Week 96 analyses, respectively). After normalizing for treatment exposure, rates of HCRU for any resource per patient-year were significantly lower for asciminib versus bosutinib: 0.25 (95% CI: 0.18-0.34) versus 0.80 (95% CI: 0.55-1.16) at the Week 24 analysis, 0.20 (95% CI: 0.15-0.27) versus 0.47 (95% CI: 0.32-0.66) at the Week 48 analysis, and 0.17 (95% CI: 0.12-0.22) versus 0.40 (95% CI: 0.27-0.55) at the Week 96 analysis. Among the hospitalized patients, mean length of hospital stay was lower for asciminib than bosutinib for most wards at all three timepoints. CONCLUSIONS: In the ASCEMBL trial, asciminib-treated patients with CML-CP in 3 L + maintained lower resource utilization compared to bosutinib over the long-term.


Asunto(s)
Antineoplásicos , Leucemia Mielógena Crónica BCR-ABL Positiva , Leucemia Mieloide de Fase Crónica , Humanos , Antineoplásicos/efectos adversos , Inhibidores de Proteínas Quinasas/uso terapéutico , Leucemia Mieloide de Fase Crónica/tratamiento farmacológico , Leucemia Mielógena Crónica BCR-ABL Positiva/tratamiento farmacológico , Nitrilos/uso terapéutico , Atención a la Salud
20.
J Dent ; 136: 104591, 2023 09.
Artículo en Inglés | MEDLINE | ID: mdl-37356560

RESUMEN

OBJECTIVES: To examine the efficacy of glycine powder air-polishing on cleaning root canal sealer-smeared dentine. METHODS: Dentine surfaces were contaminated with a smear of epoxy resin-based sealer or tricalcium silicate-based sealer. The contaminated surfaces were cleaned with saline, 75% ethanol, or air-polishing with glycine powder. Uncontaminated dentine was used as the control. The cleanliness of pulpal floor dentine was examined using scanning electron microscopy and energy dispersive X-ray analysis. The effectiveness of the three cleaning protocols was examined by testing the tensile bond strength of a self-etching adhesive to the decontaminated dentine. Resin infiltration into the dentinal tubules was identified using confocal laser scanning microscopy (CLSM). RESULTS: Morphological examination and elemental analysis indicated that glycine powder air-polishing was more effective in removing the two sealers. Tensile bond strength of adhesive-bonded dentine was significantly reduced when either sealer was cleaned with saline or ethanol. Conversely, air-polishing restored the adhesive strength of the sealer-smeared dentine to the level of the control. Longer and denser resin tags were identified with CLSM when sealers were removed with air-polishing. CONCLUSIONS: Air-polishing with glycine powder was effective in cleaning sealer-smeared dentine, as demonstrated by the rejuvenation of the tensile bond strength of a self-etching adhesive to the decontaminated dentine. CLINICAL SIGNIFICANCE: Glycine powder air-polishing improves the cleanliness of root canal sealer-smeared dentine and rejuvenates adhesive bonding effectiveness.


Asunto(s)
Recubrimiento Dental Adhesivo , Materiales de Obturación del Conducto Radicular , Materiales de Obturación del Conducto Radicular/química , Cavidad Pulpar , Polvos , Resinas Epoxi/química , Etanol , Dentina , Ensayo de Materiales
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