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1.
Cell ; 163(5): 1225-1236, 2015 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-26590424

RESUMO

The canonical Wnt signaling pathway is of paramount importance in development and disease. An emergent question is whether the upstream cascade of the canonical Wnt pathway has physiologically relevant roles beyond ß-catenin-mediated transcription, which is difficult to study due to the pervasive role of this protein. Here, we show that transcriptionally silent spermatozoa respond to Wnt signals released from the epididymis and that mice mutant for the Wnt regulator Cyclin Y-like 1 are male sterile due to immotile and malformed spermatozoa. Post-transcriptional Wnt signaling impacts spermatozoa through GSK3 by (1) reducing global protein poly-ubiquitination to maintain protein homeostasis; (2) inhibiting septin 4 phosphorylation to establish a membrane diffusion barrier in the sperm tail; and (3) inhibiting protein phosphatase 1 to initiate sperm motility. The results indicate that Wnt signaling orchestrates a rich post-transcriptional sperm maturation program and invite revisiting transcription-independent Wnt signaling in somatic cells as well.


Assuntos
Epididimo/metabolismo , Regulação da Expressão Gênica , Maturação do Esperma , Via de Sinalização Wnt , Animais , Proteína Axina/metabolismo , Ciclinas/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Masculino , Camundongos , Fosforilação , Processamento de Proteína Pós-Traducional , Processamento Pós-Transcricional do RNA , Septinas/metabolismo
2.
Genome Res ; 34(6): 952-966, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38986579

RESUMO

DEAD box (DDX) RNA helicases are a large family of ATPases, many of which have unknown functions. There is emerging evidence that besides their role in RNA biology, DDX proteins may stimulate protein kinases. To investigate if protein kinase-DDX interaction is a more widespread phenomenon, we conducted three orthogonal large-scale screens, including proteomics analysis with 32 RNA helicases, protein array profiling, and kinome-wide in vitro kinase assays. We retrieved Ser/Thr protein kinases as prominent interactors of RNA helicases and report hundreds of binary interactions. We identified members of ten protein kinase families, which bind to, and are stimulated by, DDX proteins, including CDK, CK1, CK2, DYRK, MARK, NEK, PRKC, SRPK, STE7/MAP2K, and STE20/PAK family members. We identified MARK1 in all screens and validated that DDX proteins accelerate the MARK1 catalytic rate. These findings indicate pervasive interactions between protein kinases and DEAD box RNA helicases, and provide a rich resource to explore their regulatory relationships.


Assuntos
RNA Helicases DEAD-box , RNA Helicases DEAD-box/metabolismo , RNA Helicases DEAD-box/genética , Humanos , Ligação Proteica , Proteômica/métodos , Proteínas Quinases/metabolismo , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética
3.
Nat Methods ; 21(7): 1175-1184, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38886577

RESUMO

In a human cell, thousands of replication forks simultaneously coordinate duplication of the entire genome. The rate at which this process occurs might depend on the epigenetic state of the genome and vary between, or even within, cell types. To accurately measure DNA replication speeds, we developed single-cell 5-ethynyl-2'-deoxyuridine sequencing to detect nascent replicated DNA. We observed that the DNA replication speed is not constant but increases during S phase of the cell cycle. Using genetic and pharmacological perturbations we were able to alter this acceleration of replication and conclude that DNA damage inflicted by the process of transcription limits the speed of replication during early S phase. In late S phase, during which less-transcribed regions replicate, replication accelerates and approaches its maximum speed.


Assuntos
Replicação do DNA , Análise de Célula Única , Humanos , Análise de Célula Única/métodos , Desoxiuridina/análogos & derivados , Fase S/genética , Análise de Sequência de DNA/métodos , Dano ao DNA , DNA/genética
4.
Cell ; 143(7): 1044-6, 2010 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-21183070

RESUMO

Two key events in Wnt signal transduction, receptor endocytosis and inactivation of Glycogen Synthase Kinase 3 (GSK3), remain incompletely understood. Taelman et al. (2010) discover that Wnt signaling inactivates GSK3 by sequestering the enzyme in multivesicular bodies, thus linking these two events and providing a new framework for understanding Wnt signaling.

5.
Retrovirology ; 21(1): 5, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38424561

RESUMO

Human immunodeficiency virus (HIV) and human T cell leukemia virus (HTLV) have replicative and latent stages of infection. The status of the viruses is dependent on the cells that harbour them and on different events that change the transcriptional and post-transcriptional events. Non-coding (nc)RNAs are key factors in the regulation of retrovirus replication cycles. Notably, micro (mi)RNAs and long non-coding (lnc)RNAs are important regulators that can induce switches between active transcription-replication and latency of retroviruses and have important impacts on their pathogenesis. Here, we review the functions of miRNAs and lncRNAs in the context of HIV and HTLV. We describe how specific miRNAs and lncRNAs are involved in the regulation of the viruses' transcription, post-transcriptional regulation and latency. We further discuss treatment strategies using ncRNAs for HIV and HTLV long remission, reactivation or possible cure.


Assuntos
Infecções por HIV , MicroRNAs , RNA Longo não Codificante , Humanos , MicroRNAs/genética , RNA Longo não Codificante/genética , HIV , Regulação da Expressão Gênica , RNA não Traduzido/genética , Deltaretrovirus , Retroviridae/genética
6.
J Ultrasound Med ; 2024 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-39051749

RESUMO

OBJECTIVES: To use three-dimensional anorectal ultrasonography (3D-US) to evaluate the outcome of ligation of the intersphincteric fistula tract (LIFT) in patients with crypto-glandular transsphincteric fistula and describing the patterns of healing, failure, and recurrence rate. METHODS: After classifying the fistula and determining the length of the sphincter muscle to be transected, the patients were submitted to LIFT. The accuracy of pre- and postoperative 3D-US with 360° endoprobe (16 MHz) with automatic scanning and clinical findings was evaluated against surgical findings. Three outcomes were considered: healing, failure (persistent anal fistula through the original external opening or intersphincteric), and recurrence (reappearance of the anal fistula). RESULTS: Sixty-three patients of both sexes were evaluated. The 3D-US assessment revealed primary healing in 50 (79.3%) patients, although in 6 (9.5%) cases healing was delayed and the cavity was without communication with the anal canal. The procedure failed in 9 (15.9%) and fistula recurred in 4 (6.3%), all of whom underwent a second surgery based on a new 3D-US, resulting in a 92.3% (12/13) healing rate on 3D-US. CONCLUSIONS: A 3D-US was found to be useful in the preoperative assessment of fistulas by quantifying the percentage of muscle to be transected, and in the postoperative assessment by identifying healing, types of failure, and recurrence. The 3D-US was accurate and consistent with surgical findings.

7.
Proc Natl Acad Sci U S A ; 118(34)2021 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-34417301

RESUMO

Canonical Wnt signaling plays critical roles in development and tissue renewal by regulating ß-catenin target genes. Recent evidence showed that ß-catenin-independent Wnt signaling is also required for faithful execution of mitosis. However, the targets and specific functions of mitotic Wnt signaling still remain uncharacterized. Using phosphoproteomics, we identified that Wnt signaling regulates the microtubule depolymerase KIF2A during mitosis. We found that Dishevelled recruits KIF2A via its N-terminal and motor domains, which is further promoted upon LRP6 signalosome formation during cell division. We show that Wnt signaling modulates KIF2A interaction with PLK1, which is critical for KIF2A localization at the spindle. Accordingly, inhibition of basal Wnt signaling leads to chromosome misalignment in somatic cells and pluripotent stem cells. We propose that Wnt signaling monitors KIF2A activity at the spindle poles during mitosis to ensure timely chromosome alignment. Our findings highlight a function of Wnt signaling during cell division, which could have important implications for genome maintenance, notably in stem cells.


Assuntos
Segregação de Cromossomos , Cromossomos Humanos/genética , Cinesinas/metabolismo , Mitose , Fuso Acromático/fisiologia , Via de Sinalização Wnt , Posicionamento Cromossômico , Humanos , Cinesinas/genética
8.
EMBO Rep ; 22(5): e51415, 2021 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-33786993

RESUMO

The tumour suppressors RNF43 and ZNRF3 play a central role in development and tissue homeostasis by promoting the turnover of the Wnt receptors LRP6 and Frizzled (FZD). The stem cell growth factor R-spondin induces auto-ubiquitination and membrane clearance of ZNRF3/RNF43 to promote Wnt signalling. However, the deubiquitinase stabilising ZNRF3/RNF43 at the plasma membrane remains unknown. Here, we show that the USP42 antagonises R-spondin by protecting ZNRF3/RNF43 from ubiquitin-dependent clearance. USP42 binds to the Dishevelled interacting region (DIR) of ZNRF3 and stalls the R-spondin-LGR4-ZNRF3 ternary complex by deubiquitinating ZNRF3. Accordingly, USP42 increases the turnover of LRP6 and Frizzled (FZD) receptors and inhibits Wnt signalling. Furthermore, we show that USP42 functions as a roadblock for paracrine Wnt signalling in colon cancer cells and mouse small intestinal organoids. We provide new mechanistic insights into the regulation R-spondin and conclude that USP42 is crucial for ZNRF3/RNF43 stabilisation at the cell surface.


Assuntos
Trombospondinas , Ubiquitina-Proteína Ligases , Animais , Camundongos , Receptores Acoplados a Proteínas G/genética , Trombospondinas/genética , Trombospondinas/metabolismo , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação , Via de Sinalização Wnt
9.
Dis Colon Rectum ; 66(12): 1555-1561, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37606632

RESUMO

BACKGROUND: Few studies measured the pre- and postoperative anatomic and functional anal canal using 3-dimensional endoanal ultrasound and anal manometry and correlated sphincter division with fecal incontinence, severity, and function. OBJECTIVE: To assess the incidence of fecal incontinence in patients who underwent internal anal sphincter division for anal fissure or intersphincteric anal fistula and correlate severity of symptoms with percentage of divided muscle, anatomical measurements, and anal pressures. DESIGN: Prospective cohort study. SETTINGS: Colorectal surgery unit, tertiary referral center. PATIENTS: Patients underwent clinical assessment using the Cleveland Clinic Florida Fecal Incontinence score for severity of symptoms, manometry, and ultrasound. MAIN OUTCOMES MEASURES: Ultrasound measurements of length, percentage, and angle of divided internal anal sphincter, anterior external anal sphincter, posterior external anal sphincter plus puborectalis, and gap lengths. RESULTS: Sixty-three women (mean age, 44 years) were divided into 2 groups: 30 (48%) underwent fistulotomy for intersphincteric anal fistula and 33 (52%) underwent sphincterotomy for chronic anal fissure with high anal resting pressure. Forty-six percent experienced some measure of fecal incontinence after internal anal sphincter division. Incidence of fecal incontinence, severity of symptoms, and angle of the divided internal anal sphincter were similar between the groups. Length and percentage of the divided internal anal sphincter were significantly higher in the intersphincteric anal fistula. External anal sphincter and external anal sphincter plus puborectalis lengths were similar in both groups. Gap length was significantly longer in chronic anal fissures with high anal resting pressure. LIMITATIONS: Single-institution, exclusion of males. CONCLUSIONS: Fecal incontinence was reported in half of the patients who underwent internal anal sphincter division. Despite the greater length and percentage of internal anal sphincter division in patients who underwent fistulotomy, incidence and severity of fecal incontinence were similar in both groups. Three-dimensional endoanal ultrasound showed greater gap length in the sphincterotomy group, which may be functionally significant after the division of the shorter internal anal sphincter but with a similar impact on fecal incontinence in both groups. IMPACTO DE LA DIVISIN DEL ESFNTER ANAL INTERNO EN LA ALTERACIN DE LA CONTINENCIA EN PACIENTES DE SEXO FEMENINO: ANTECEDENTES:Pocos estudios han medido el canal anal anatómico y funcional antes y después de la cirugía mediante ecografía endoanal tridimensional y manometría anal, y correlacionado la división del esfínter con la incontinencia fecal, la gravedad y la función.OBJETIVO:Evaluar la incidencia de incontinencia fecal en pacientes sometidos a división del esfínter anal interno por fisura anal o fístula anal interesfinteriana, y correlacionar la gravedad de los síntomas con el porcentaje de músculo dividido, las medidas anatómicas y las presiones anales.DISEÑO:Estudio de cohorte prospectivo.AJUSTE:Unidad de cirugía colorrectal, centro de referencia de tercer nivel.PACIENTES:Pacientes sometidos a una evaluación clínica utilizando la puntuación de incontinencia fecal de Cleveland Clinic Florida para la gravedad de los síntomas, la manometría y la ecografía.PRINCIPALES MEDIDAS DE RESULTADO:Mediciones por ultrasonido de la longitud, el porcentaje y el ángulo del esfínter anal interno dividido y el esfínter anal externo anterior, el esfínter anal externo posterior más el puborrectal y las longitudes del espacio.RESULTADOS:Sesenta y tres mujeres (edad media, 44 años) se dividieron en 2 grupos: 30 (48%) sometidos a fistulotomía por fístula anal interesfinteriana y 33 (52%) sometidos a esfinterotomía por fisura anal crónica con alta presión anal en reposo. El 46% experimentó algún grado de incontinencia fecal después de la división del esfínter anal interno. La incidencia de incontinencia fecal, la gravedad de los síntomas y el ángulo del esfínter anal interno dividido fueron similares entre los grupos. La longitud y el porcentaje del esfínter anal interno dividido fueron significativamente mayores en la fístula anal interesfinteriana. Las longitudes del esfínter anal externo y del esfínter anal externo más el puborrectal fueron similares en ambos grupos. La longitud del espacio fue significativamente mayor en la fisura anal crónica con alta presión anal en reposo.LIMITACIONES:Institución única, exclusión de varones.CONCLUSIÓN:La incontinencia fecal se reportó en la mitad de los pacientes sometidos a división del esfínter anal interno. A pesar de la mayor longitud y porcentaje de división del esfínter anal interno en los pacientes sometidos a fistulotomía, la incidencia y gravedad de la incontinencia fecal fue similar en ambos grupos. La ecografía endoanal tridimensional mostró una mayor longitud del espacio en el grupo de esfinterotomía, lo que puede ser funcionalmente significativo después de la división del esfínter anal interno más corto, pero con un impacto similar en la incontinencia fecal en ambos grupos. (Traducción-Dr. Fidel Ruiz Healy ).


Assuntos
Incontinência Fecal , Fissura Anal , Fístula Retal , Masculino , Humanos , Feminino , Adulto , Canal Anal/diagnóstico por imagem , Canal Anal/cirurgia , Incontinência Fecal/epidemiologia , Incontinência Fecal/etiologia , Estudos Prospectivos , Fístula Retal/epidemiologia , Fístula Retal/cirurgia , Estudos Retrospectivos
10.
Inorg Chem ; 62(20): 7834-7842, 2023 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-37156094

RESUMO

The incorporation of electroactive organic building blocks into coordination polymers (CPs) and metal-organic frameworks (MOFs) offers a promising approach for adding electronic functionalities such as redox activity, electrical conductivity, and luminescence to these materials. The incorporation of perylene moieties into CPs is, in particular, of great interest due to its potential to introduce both luminescence and redox properties. Herein, we present an innovative synthesis method for producing a family of highly crystalline and stable coordination polymers based on perylene-3,4,9,10-tetracarboxylate (PTC) and various transition metals (TMs = Co, Ni, and Zn) with an isostructural framework. The crystal structure of the PTC-TM CPs, obtained through powder X-ray diffraction and Rietveld refinement, provides valuable insights into the composition and organization of the building blocks within the CP. The perylene moieties are arranged in a herringbone pattern, with short distances between adjacent ligands, which contributes to the dense and highly organized framework of the material. The photophysical properties of PTC-Zn were thoroughly studied, revealing the presence of J-aggregation-based and monomer-like emission bands. These bands were experimentally identified, and their behavior was further understood through the use of quantum-chemical calculations. Solid-state cyclic voltammetry experiments on PTC-TMs showed that the perylene redox properties are maintained within the CP framework. This study presents a simple and effective approach for synthesizing highly stable and crystalline perylene-based CPs with tunable optical and electrochemical properties in the solid state.

11.
Health Care Manag Sci ; 26(2): 217-237, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37099041

RESUMO

Organ transplant is one of the best options for many medical conditions, and in many cases, it may be the only treatment option. Recent evidence suggests, however, that the COVID-19 pandemic might have detrimentally affected the provision of this type of healthcare services. The main purpose of this article is to use Data Envelopment Analysis and the Malmquist Index to assess the impact that the pandemic caused by the novel coronavirus SARS-CoV-2 had on the provision of solid organ transplant services. To this purpose, we use three complementary models, each focusing on specific aspects of the organ donation and transplantation process, and data from Brazil, which has one of the most extensive public organ transplant programs in the world. Using data from 17 States plus the Federal District, the results of our analysis show a significant drop in the performance of the services in terms of the organ donation and transplantation process from 2018 to 2020, but the results also indicate that not all aspects of the process and States were equally affected. Furthermore, by using different models, this research also allows us to gain a more comprehensive and informative assessment of the performance of the States in delivering this type of service and identify opportunities for reciprocal learning, expanding our knowledge on this important issue and offering opportunities for further research.


Assuntos
COVID-19 , Transplante de Órgãos , Obtenção de Tecidos e Órgãos , Humanos , SARS-CoV-2 , Pandemias , Transplante de Órgãos/métodos
12.
Molecules ; 28(14)2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37513324

RESUMO

The growing worldwide cancer incidence, coupled to the increasing occurrence of multidrug cancer resistance, requires a continuous effort towards the identification of new leads for cancer management. In this work, two C-scorpionate complexes, [FeCl2(κ3-Tpm)] (1) and [Co(κ3-TpmOH)2](NO3)2 (2), (Tpm = hydrotris(pyrazol-1-yl)methane and TpmOH = 2,2,2-tris(pyrazol-1-yl)ethanol), were studied as potential scaffolds for future anticancer drug development. Their cytotoxicity and cell migration inhibitory activity were analyzed, and an untargeted metabolomics approach was employed to elucidate the biological processes significantly affected by these two complexes, using two tumoral cell lines (B16 and HCT116) and a non-tumoral cell line (HaCaT). While [FeCl2(κ3-Tpm)] did not display a significant cytotoxicity, [Co(κ3-TpmOH)2](NO3)2 was particularly cytotoxic against the HCT116 cell line. While [Co(κ3-TpmOH)2](NO3)2 significantly inhibited cell migration in all tested cell lines, [FeCl2(κ3-Tpm)] displayed a mixed activity. From a metabolomics perspective, exposure to [FeCl2(κ3-Tpm)] was associated with changes in various metabolic pathways involving tyrosine, where iron-dependent enzymes are particularly relevant. On the other hand, [Co(κ3-TpmOH)2](NO3)2 was associated with dysregulation of cell adhesion and membrane structural pathways, suggesting that its antiproliferative and anti-migration properties could be due to changes in the overall cellular adhesion mechanisms.


Assuntos
Antineoplásicos , Complexos de Coordenação , Neoplasias , Humanos , Antineoplásicos/farmacologia , Linhagem Celular , Complexos de Coordenação/química
13.
Socioecon Plann Sci ; 87: 101588, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37255587

RESUMO

The topic of regional economic resilience has been the subject of intense debate in the academic and political fields over the past decade and gained a new sense of urgency because of the pandemic caused by the SARS-CoV-2 virus as territories faced relevant impacts on their economies and social structures. The economic downturn, the increase in unemployment, and the deterioration of social conditions lead policy makers to search for solutions to make their territories more resilient to this type of event. The current article discusses how multicriteria decision analysis (MCDA) was used to help a Portuguese Intermunicipal Community, formed by 16 councils, develop a strategy to make its territory more cohesive, competitive, sustainable, and resilient. In addition to discussing an innovative application of a MCDA technique, this article illustrates how, through a MCDA approach, it was possible to reach a consensus among several policymakers, despite each of them having their own political agendas.

14.
Clin Sci (Lond) ; 136(17): 1281-1301, 2022 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-35894060

RESUMO

Cardiac transplantation of adipose-derived stem cells (ASC) modulates the post-myocardial infarction (post-MI) repair response. Biomolecules secreted or shuttled within extracellular vesicles, such as exosomes, may participate in the concerted response. We investigated the exosome's microRNAs due to their capacity to fine-tune gene expression, potentially affecting the multicellular repair response. We profiled and quantified rat ASC-exosome miRNAs and used bioinformatics to select uncharacterized miRNAs down-regulated in post-MI related to cardiac repair. We selected and validated miR-196a-5p and miR-425-5p as candidates for the concerted response in neonatal cardiomyocytes, cardiac fibroblasts, endothelial cells, and macrophages using a high-content screening platform. Both miRNAs prevented cardiomyocyte ischemia-induced mitochondrial dysfunction and reactive oxygen species production, increased angiogenesis, and polarized macrophages toward the anti-inflammatory M2 immunophenotype. Moreover, miR-196a-5p reduced and reversed myofibroblast activation and decreased collagen expression. Our data provide evidence that the exosome-derived miR-196a-5p and miR-425-5p influence biological processes critical to the concerted multicellular repair response post-MI.


Assuntos
Exossomos , MicroRNAs , Infarto do Miocárdio , Tecido Adiposo/metabolismo , Animais , Células Endoteliais/metabolismo , Exossomos/genética , Exossomos/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Infarto do Miocárdio/genética , Infarto do Miocárdio/metabolismo , Infarto do Miocárdio/terapia , Miócitos Cardíacos/metabolismo , Ratos , Células-Tronco
15.
AJR Am J Roentgenol ; 219(5): 804-812, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35731098

RESUMO

BACKGROUND. Washout CT is commonly used to evaluate indeterminate adrenal nodules, although its diagnostic performance is poorly established in true adrenal incidentalomas. OBJECTIVE. The purpose of this study was to compare, in patients without a known malignancy history, the prevalence of malignancy for incidental adrenal nodules with unenhanced attenuation more than 10 HU that do and do not show absolute washout of 60% or more, thereby determining the diagnostic performance of washout CT for differentiating benign from malignant incidental adrenal nodules. METHODS. This retrospective six-institution study included 299 patients (mean age, 57.3 years; 180 women, 119 men) without known malignancy or suspicion for functioning adrenal tumor who underwent washout CT, which showed a total of 336 adrenal nodules with a short-axis diameter of 1 cm or more, homogeneity, and unenhanced attenuation over 10 HU. The date of the first CT ranged across institutions from November 1, 2003, to January 1, 2017. Washout was determined for all nodules. Reference standard was pathology (n = 54), imaging follow-up (≥ 1 year) (n = 269), or clinical follow-up (≥ 5 years) (n = 13). RESULTS. Prevalence of malignancy among all nodules, nodules less than 4 cm, and nodules 4 cm or more was 1.5% (5/336; 95% CI, 0.5-3.4%), 0.3% (1/317; 95% CI, 0.0-1.7%), and 21.1% (4/19; 95% CI, 6.1-45.6%), respectively. Prevalence of malignancy was not significantly different for nodules smaller than 4 cm with (0% [0/241]; 95% CI, 0.0-1.2%) and without (1.3% [1/76]; 95% CI, 0.0-7.1%) washout of 60% or more (p = .08) or for nodules 4 cm or larger with (16.7% [1/6]; 95% CI, 0.4-64.1%) and without (23.1% [3/13]; 95% CI, 5.0-53.8%) washout of 60% or more (p = .75). Washout of 60% or more was observed in 75.5% (243/322; 95% CI, 70.4-80.1%) of benign nodules (excluding pheochromocytomas), 20.0% (1/5; 95% CI, 0.5-71.6%) of malignant nodules, and 33.3% (3/9; 95% CI, 7.5-70.1%) of pheochromocytomas. For differentiating benign nodules from malignant nodules and pheochromocytomas, washout of 60% or more had 77.5% sensitivity, 70.0% specificity, 98.8% PPV, and 9.2% NPV among nodules smaller than 4 cm. CONCLUSION. Prevalence of malignancy is low among incidental homogeneous adrenal nodules smaller than 4 cm with unenhanced attenuation more than 10 HU and does not significantly differ between those with and without washout of 60% or more; wash-out of 60% or more has suboptimal performance for characterizing nodules as benign. CLINICAL IMPACT. Washout CT has limited utility in evaluating incidental adrenal nodules in patients without known malignancy.


Assuntos
Neoplasias das Glândulas Suprarrenais , Feocromocitoma , Masculino , Humanos , Feminino , Pessoa de Meia-Idade , Neoplasias das Glândulas Suprarrenais/diagnóstico por imagem , Neoplasias das Glândulas Suprarrenais/epidemiologia , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Prevalência
16.
Mol Cell ; 54(4): 663-74, 2014 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-24837680

RESUMO

Canonical Wnt signaling is thought to regulate cell behavior mainly by inducing ß-catenin-dependent transcription of target genes. In proliferating cells Wnt signaling peaks in the G2/M phase of the cell cycle, but the significance of this "mitotic Wnt signaling" is unclear. Here we introduce Wnt-dependent stabilization of proteins (Wnt/STOP), which is independent of ß-catenin and peaks during mitosis. We show that Wnt/STOP plays a critical role in protecting proteins, including c-MYC, from GSK3-dependent polyubiquitination and degradation. Wnt/STOP signaling increases cellular protein levels and cell size. Wnt/STOP, rather than ß-catenin signaling, is the dominant mode of Wnt signaling in several cancer cell lines, where it is required for cell growth. We propose that Wnt/STOP signaling slows down protein degradation as cells prepare to divide.


Assuntos
Tamanho Celular , Mitose , Proteínas Wnt/metabolismo , Via de Sinalização Wnt , Linhagem Celular Tumoral , Proliferação de Células , Regulação da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Células HEK293 , Células HeLa , Humanos , Análise Serial de Proteínas , Estabilidade Proteica , Proteínas Proto-Oncogênicas c-myc/genética , Proteínas Proto-Oncogênicas c-myc/metabolismo , Ubiquitinação , Proteínas Wnt/genética
17.
Int J Mol Sci ; 23(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36293386

RESUMO

Multidrug-resistant bacteria represent a global health and economic burden that urgently calls for new technologies to combat bacterial antimicrobial resistance. Here, we developed novel nanocomposites (NCPs) based on chitosan that display different degrees of acetylation (DAs), and conjugated polymer cyano-substituted poly(p-phenylene vinylene) (CNPPV) as an alternative approach to inactivate Gram-negative (E. coli) and Gram-positive (S. aureus) bacteria. Chitosan's structure was confirmed through FT-Raman spectroscopy. Bactericidal and photobactericidal activities of NCPs were tested under dark and blue-light irradiation conditions, respectively. Hydrodynamic size and aqueous stability were determined by DLS, zeta potential (ZP) and time-domain NMR. TEM micrographs of NCPs were obtained, and their capacity of generating reactive oxygen species (ROS) under blue illumination was also characterized. Meaningful variations on ZP and relaxation time T2 confirmed successful physical attachment of chitosan/CNPPV. All NCPs exhibited a similar and shrunken spherical shape according to TEM. A lower DA is responsible for driving higher bactericidal performance alongside the synergistic effect from CNPPV, lower nanosized distribution profile and higher positive charged surface. ROS production was proportionally found in NCPs with and without CNPPV by decreasing the DA, leading to a remarkable photobactericidal effect under blue-light irradiation. Overall, our findings indicate that chitosan/CNPPV NCPs may constitute a valuable asset for the development of innovative strategies for inactivation and/or photoinactivation of bacteria.


Assuntos
Quitosana , Nanocompostos , Humanos , Quitosana/farmacologia , Quitosana/química , Espécies Reativas de Oxigênio/farmacologia , Staphylococcus aureus , Escherichia coli , Nanocompostos/química , Antibacterianos/farmacologia , Antibacterianos/química , Bactérias
18.
J Neurochem ; 156(5): 692-701, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32743826

RESUMO

Most lysosomal storage diseases (LSDs) have a significant neurological component, including types 2 and 3 Gaucher disease (neuronal forms of Gaucher disease; nGD). No therapies are currently available for nGD since the recombinant enzymes used in the systemic form of Gaucher disease do not cross the blood-brain barrier (BBB). However, a number of promising approaches are currently being tested, including substrate reduction therapy (SRT), in which partial inhibition of the synthesis of the glycosphingolipids (GSLs) that accumulate in nGD lowers their accumulation. We now induce nGD in mice by injection with conduritol B-epoxide (CBE), an irreversible inhibitor of acid beta-glucosidase (GCase), the enzyme defective in nGD, with or without co-injection with Genz-667161, a prototype for SRT which crosses the BBB. Significant neuropathology, and a reduction in lifespan, was observed upon CBE injection, and this was largely reversed by co-injection with Genz-667161, along with a reduction in glucosylceramide and glucosylsphingosine levels. Analysis of gene expression by RNAseq revealed that Genz-667161 largely reversed the changes in genes and pathways that were differentially expressed upon CBE injection, specifically pathways of GSL metabolism, lipoproteins and other lipid metabolic pathways, lipid droplets, astrocyte activation, neuronal function, and to some extent, neuroinflammation. Together, this demonstrates the efficacy of SRT to reverse the effects of substrate accumulation on pathological components and pathways in nGD brain.


Assuntos
Modelos Animais de Doenças , Doença de Gaucher/metabolismo , Doença de Gaucher/patologia , Glucosilceramidase/antagonistas & inibidores , Glicoesfingolipídeos/antagonistas & inibidores , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Inibidores Enzimáticos/farmacologia , Inibidores Enzimáticos/uso terapêutico , Feminino , Doença de Gaucher/tratamento farmacológico , Glucosilceramidase/metabolismo , Glicoesfingolipídeos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Especificidade por Substrato/efeitos dos fármacos , Especificidade por Substrato/fisiologia
19.
Mov Disord ; 36(3): 716-728, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33200461

RESUMO

BACKGROUND: Parkinson's disease psychosis is a prevalent yet underreported and understudied nonmotor manifestation of Parkinson's disease and, arguably, the most debilitating. It is unknown if α-synuclein plays a role in psychosis, and if so, this endophenotype may be crucial for elucidating the neurodegenerative process. OBJECTIVES: We sought to dissect the underlying neurobiology of novelty-induced hyperactivity, reminiscent of psychosis-like behavior, in human α-synuclein BAC rats. RESULTS: Herein, we demonstrate a prodromal psychosis-like phenotype, including late-onset sensorimotor gating disruption, striatal hyperdopaminergic signaling, and persistent novelty-induced hyperactivity (up to 18 months), albeit reduced baseline locomotor activity, that is augmented by d-amphetamine and reversed by classical and atypical antipsychotics. MicroRNA-mediated α-synuclein downregulation in the ventral midbrain rescues the hyperactive phenotype and restores striatal dopamine levels. This phenotype is accompanied by an abundance of age-, brain region- and gene dose-dependent aberrant α-synuclein, including hyperphosphorylation, C-terminal truncation, aggregation pathology, and mild nigral neurodegeneration (27%). CONCLUSIONS: Our findings demonstrate a potential role of α-synuclein in Parkinson's disease psychosis and provide evidence of region-specific perturbations prior to neurodegeneration phenoconversion. The reported phenotype coincides with the latest clinical findings that suggest a premotor hyperdopaminergic state may occur, while at the same time, premotor psychotic symptoms are increasingly being recognized. © 2020 International Parkinson and Movement Disorder Society.


Assuntos
Doença de Parkinson , Transtornos Psicóticos , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Camundongos Transgênicos , Transtornos Psicóticos/genética , Ratos , Ratos Transgênicos , Substância Negra/metabolismo , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
20.
Int J Mol Sci ; 22(23)2021 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-34884877

RESUMO

Doxorubicin (Dox) is one of the most widely used treatments for breast cancer, although limited by the well-documented cardiotoxicity and other off-target effects. Mesenchymal stem cell (MSC) secretome has shown immunomodulatory and regenerative properties, further potentiated under 3D conditions. This work aimed to uncover the effect of the MSC-derived secretome from 3D (CM3D) or 2D (CM2D) cultures, in human malignant breast cells (MDA-MB-231), non-tumor breast epithelial cells (MCF10A) and differentiated AC16 cardiomyocytes, co-treated with Dox. A comprehensive proteomic analysis of CM3D/CM2D was also performed to unravel the underlying mechanism. CM3D/CM2D co-incubation with Dox revealed no significant differences in MDA-MB-231 viability when compared to Dox alone, whereas MCF10A and AC16 viability was consistently improved in Dox+CM3D-treated cells. Moreover, neither CM2D nor CM3D affected Dox anti-migratory and anti-invasive effects in MDA-MB-231. Notably, Ge-LC-MS/MS proteomic analysis revealed that CM3D displayed protective features that might be linked to the regulation of cell proliferation (CAPN1, CST1, LAMC2, RANBP3), migration (CCN3, MMP8, PDCD5), invasion (TIMP1/2), oxidative stress (COX6B1, AIFM1, CD9, GSR) and inflammation (CCN3, ANXA5, CDH13, GDF15). Overall, CM3D decreased Dox-induced cytotoxicity in non-tumor cells, without compromising Dox chemotherapeutic profile in malignant cells, suggesting its potential use as a chemotherapy adjuvant to reduce off-target side effects.


Assuntos
Neoplasias da Mama/terapia , Doxorrubicina/farmacologia , Imunomodulação , Células-Tronco Mesenquimais/metabolismo , Miócitos Cardíacos/efeitos dos fármacos , Secretoma , Neoplasias da Mama/tratamento farmacológico , Cardiotoxicidade/prevenção & controle , Linhagem Celular , Linhagem Celular Tumoral , Terapia Combinada , Doxorrubicina/uso terapêutico , Feminino , Humanos , Estresse Oxidativo
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