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1.
EMBO Rep ; 23(2): e48754, 2022 02 03.
Artigo em Inglês | MEDLINE | ID: mdl-34994490

RESUMO

Mitochondria are unavoidably subject to organellar stress resulting from exposure to a range of reactive molecular species. Consequently, cells operate a poorly understood quality control programme of mitophagy to facilitate elimination of dysfunctional mitochondria. Here, we used a model stressor, deferiprone (DFP), to investigate the molecular basis for stress-induced mitophagy. We show that mitochondrial fission 1 protein (Fis1) is required for DFP-induced mitophagy and that Fis1 is SUMOylated at K149, an amino acid residue critical for Fis1 mitochondrial localization. We find that DFP treatment leads to the stabilization of the SUMO protease SENP3, which is mediated by downregulation of the E3 ubiquitin (Ub) ligase CHIP. SENP3 is responsible for Fis1 deSUMOylation and depletion of SENP3 abolishes DFP-induced mitophagy. Furthermore, preventing Fis1 SUMOylation by conservative K149R mutation enhances Fis1 mitochondrial localization. Critically, expressing a Fis1 K149R mutant restores DFP-induced mitophagy in SENP3-depleted cells. Thus, we propose a model in which SENP3-mediated deSUMOylation facilitates Fis1 mitochondrial localization to underpin stress-induced mitophagy.


Assuntos
Mitocôndrias , Peptídeo Hidrolases , Autofagia , Cisteína Endopeptidases/genética , Cisteína Endopeptidases/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/genética , Proteínas Mitocondriais/metabolismo , Mitofagia , Peptídeo Hidrolases/metabolismo
2.
Arch Sex Behav ; 53(2): 525-541, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37943472

RESUMO

Experiences of heterosexism are rampant online, where bias and harassment against LGBTQ+ individuals spread conveniently and widely. Yet, research has been limited in understanding the exposure to online heterosexism among LGBTQ+ individuals partly due to the lack of a quantitative measure to advance this research. Thus, the current study developed and examined the psychometric properties of the Perceived Online Heterosexism Scale (POHS). Items were developed via a literature review, a survey of social media platforms, and an expert review. Exploratory (N = 288) and confirmatory (N = 653) factor analyses yielded a 4-factor structure and produced a 20-item scale with the following subscales: (1) Heterosexist Cyberaggression (4 items), (2) Online Heterosexist Stereotyping (4 items), (3) Online Exposure to Systemic Heterosexism (8 items), and (4) Heterosexist Online Media (four items). Internal consistency estimates ranged from .91 to .96, and the POHS accounted for 65.9% of the variance. Examination of a second-order model suggested that a total scale score can also be used. Initial construct validity was evidenced as POHS scores were associated with an existing heterosexism measure, anxiety and depressive symptoms, internalized heterosexism, and LGBTQ+ community connectedness in line with theory and empirical evidence. Implications for research practice are discussed.


Assuntos
Saúde Mental , Minorias Sexuais e de Gênero , Humanos , Ansiedade , Psicometria , Estereotipagem , Masculino , Feminino
3.
Proc Natl Acad Sci U S A ; 117(6): 2835-2845, 2020 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-31974306

RESUMO

Recording cell-specific neuronal activity while monitoring behaviors of freely moving subjects can provide some of the most significant insights into brain function. Current means for monitoring calcium dynamics in genetically targeted populations of neurons rely on delivery of light and recording of fluorescent signals through optical fibers that can reduce subject mobility, induce motion artifacts, and limit experimental paradigms to isolated subjects in open, two-dimensional (2D) spaces. Wireless alternatives eliminate constraints associated with optical fibers, but their use of head stages with batteries adds bulk and weight that can affect behaviors, with limited operational lifetimes. The systems introduced here avoid drawbacks of both types of technologies, by combining highly miniaturized electronics and energy harvesters with injectable photometric modules in a class of fully wireless, battery-free photometer that is fully implantable subdermally to allow for the interrogation of neural dynamics in freely behaving subjects, without limitations set by fiber optic tethers or operational lifetimes constrained by traditional power supplies. The unique capabilities of these systems, their compatibility with magnetic resonant imaging and computed tomography and the ability to manufacture them with techniques in widespread use for consumer electronics, suggest a potential for broad adoption in neuroscience research.


Assuntos
Encéfalo/fisiologia , Fotometria/métodos , Animais , Encéfalo/diagnóstico por imagem , Encéfalo/cirurgia , Desenho de Equipamento , Imageamento por Ressonância Magnética , Camundongos , Camundongos Endogâmicos C57BL , Fotometria/instrumentação , Próteses e Implantes , Tecnologia sem Fio/instrumentação
4.
J Community Psychol ; 51(4): 1634-1652, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36170463

RESUMO

Extant literature suggests that racism is associated with difficult emotional reactions and feelings of social disconnect among White individuals. These feelings of social disconnect may be particularly salient in today's digital era in which racism against racial minority individuals is conveniently and frequently witnessed via online platforms. Thus, we examined whether witnessing racism online may be associated with feelings of loneliness among White emerging adults. We also tested whether anti-racism advocacy buffered loneliness given its potential for relationship building and community organizing to promote racial justice and equity. Using data from 227 White emerging adults (Mage = 20.86, SD = 4.82), we conducted a latent moderated structural equation modeling to test individual and institutional anti-racism advocacy as moderators in the link between witnessing racism online (racial victimization of racial minority individuals in online interactions and online content on cultural devaluation/systemic racism against racial minority individuals) and loneliness. Greater exposure to online content on systemic racism and cultural devaluation of racial minority groups significantly predicted greater loneliness. Engagement in individual anti-racism advocacy (mean to high levels) buffered this link. White allies must engage in anti-racism practice to address racism in our society, and our findings advance our understanding of the associated psychosocial costs. Implications for research and practice are discussed.


Assuntos
Antirracismo , Solidão , Racismo , População Branca , Adulto , Humanos , Adulto Jovem , Minorias Étnicas e Raciais , Adolescente , Internet
5.
Nat Mater ; 20(11): 1559-1570, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34326506

RESUMO

Flexible electronic/optoelectronic systems that can intimately integrate onto the surfaces of vital organ systems have the potential to offer revolutionary diagnostic and therapeutic capabilities relevant to a wide spectrum of diseases and disorders. The critical interfaces between such technologies and living tissues must provide soft mechanical coupling and efficient optical/electrical/chemical exchange. Here, we introduce a functional adhesive bioelectronic-tissue interface material, in the forms of mechanically compliant, electrically conductive, and optically transparent encapsulating coatings, interfacial layers or supporting matrices. These materials strongly bond both to the surfaces of the devices and to those of different internal organs, with stable adhesion for several days to months, in chemistries that can be tailored to bioresorb at controlled rates. Experimental demonstrations in live animal models include device applications that range from battery-free optoelectronic systems for deep-brain optogenetics and subdermal phototherapy to wireless millimetre-scale pacemakers and flexible multielectrode epicardial arrays. These advances have immediate applicability across nearly all types of bioelectronic/optoelectronic system currently used in animal model studies, and they also have the potential for future treatment of life-threatening diseases and disorders in humans.


Assuntos
Implantes Absorvíveis , Adesivos , Animais , Condutividade Elétrica , Eletrônica
6.
Haemophilia ; 26 Suppl 1: 20-30, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32017338

RESUMO

BACKGROUND: Despite the high prevalence of overweight and obesity in the United States, few studies have assessed the impact of obesity on haemophilia-specific outcomes or experiences/perceptions of healthcare providers (HCPs) treating haemophilia. AIM: The Awareness, Care and Treatment In Obesity maNagement to inform Haemophilia Obesity Patient Empowerment (ACTION-TO-HOPE) study was designed to identify HCP insights on the unique challenges of patients with haemophilia and obesity/overweight (PwHO) and the barriers to chronic weight management. METHODS: An online survey collected data from haemophilia treatment centre-based HCPs. Respondents included 10 adults and 29 paediatric haematologists, 27 nurses/nurse practitioners/physician assistants, 22 physical therapists and 17 social workers. RESULTS: Almost all HCPs rated obesity of moderate/high concern and reported that weight significantly affects future health and has an impact on life expectancy, yet fewer than 60% reported discussing the impact of weight on health with their patients. HCPs reported that few PwHO tried to lose weight; not many were 'successful'. HCPs perceived a desire to feel better physically and joint pain as top motivating factors. HCPs believe that PwHO would have less joint bleeding and pain and greater mobility if they lost weight. HCPs viewed lack of exercise and food preferences/habits as the biggest barriers to initiating/maintaining weight loss and therefore recommended increasing exercise and healthier eating to their patients. However, physical activity in this patient population is limited and requires advice and support. CONCLUSIONS: Most HCPs appreciated the impact of obesity on joint bleeding, pain, and function and quality of life. Reduced food intake and increased activity are the most commonly recommended weight-loss strategies but the least likely to be successful. HCPs desire additional education/materials to understand weight management for PwHO.


Assuntos
Pessoal de Saúde , Hemofilia A , Manejo da Obesidade , Obesidade , Participação do Paciente , Qualidade de Vida , Adolescente , Adulto , Idoso , Feminino , Hemofilia A/epidemiologia , Hemofilia A/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Obesidade/epidemiologia , Obesidade/terapia , Estados Unidos/epidemiologia
7.
Angew Chem Int Ed Engl ; 59(1): 388-394, 2020 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-31750611

RESUMO

Our lab has developed a new series of self-immolative MR agents for the rapid detection of enzyme activity in mouse models expressing ß-galactosidase (ß-gal). We investigated two molecular architectures to create agents that detect ß-gal activity by modulating the coordination of water to GdIII . The first is an intermolecular approach, wherein we designed several structural isomers to maximize coordination of endogenous carbonate ions. The second involves an intramolecular mechanism for q modulation. We incorporated a pendant coordinating carboxylate ligand with a 2, 4, 6, or 8 carbon linker to saturate ligand coordination to the GdIII ion. This renders the agent ineffective. We show that one agent in particular (6-C pendant carboxylate) is an extremely effective MR reporter for the detection of enzyme activity in a mouse model expressing ß-gal.


Assuntos
Imageamento por Ressonância Magnética/métodos , beta-Galactosidase/metabolismo , Animais , Modelos Animais de Doenças , Camundongos , Estrutura Molecular
8.
Circulation ; 136(16): 1477-1491, 2017 Oct 17.
Artigo em Inglês | MEDLINE | ID: mdl-28778945

RESUMO

BACKGROUND: Cardiomyopathy and arrhythmias are under significant genetic influence. Here, we studied a family with dilated cardiomyopathy and associated conduction system disease in whom prior clinical cardiac gene panel testing was unrevealing. METHODS: Whole-genome sequencing and induced pluripotent stem cells were used to examine a family with dilated cardiomyopathy and atrial and ventricular arrhythmias. We also characterized a mouse model with heterozygous and homozygous deletion of Mybphl. RESULTS: Whole-genome sequencing identified a premature stop codon, R255X, in the MYBPHL gene encoding MyBP-HL (myosin-binding protein-H like), a novel member of the myosin-binding protein family. MYBPHL was found to have high atrial expression with low ventricular expression. We determined that MyBP-HL protein was myofilament associated in the atria, and truncated MyBP-HL protein failed to incorporate into the myofilament. Human cell modeling demonstrated reduced expression from the mutant MYBPHL allele. Echocardiography of Mybphl heterozygous and null mouse hearts exhibited a 36% reduction in fractional shortening and an increased diastolic ventricular chamber size. Atria weight normalized to total heart weight was significantly increased in Mybphl heterozygous and null mice. Using a reporter system, we detected robust expression of Mybphl in the atria, and in discrete puncta throughout the right ventricular wall and septum, as well. Telemetric electrocardiogram recordings in Mybphl mice revealed cardiac conduction system abnormalities with aberrant atrioventricular conduction and an increased rate of arrhythmia in heterozygous and null mice. CONCLUSIONS: The findings of reduced ventricular function and conduction system defects in Mybphl mice support that MYBPHL truncations may increase risk for human arrhythmias and cardiomyopathy.


Assuntos
Arritmias Cardíacas/metabolismo , Cardiomiopatia Dilatada/metabolismo , Proteínas do Citoesqueleto/metabolismo , Células-Tronco Pluripotentes Induzidas/metabolismo , Miócitos Cardíacos/metabolismo , Miofibrilas/metabolismo , Animais , Arritmias Cardíacas/diagnóstico , Arritmias Cardíacas/genética , Arritmias Cardíacas/fisiopatologia , Função Atrial , Cardiomiopatia Dilatada/diagnóstico por imagem , Cardiomiopatia Dilatada/genética , Cardiomiopatia Dilatada/fisiopatologia , Células Cultivadas , Proteínas do Citoesqueleto/genética , Modelos Animais de Doenças , Ecocardiografia , Eletrocardiografia , Predisposição Genética para Doença , Átrios do Coração/metabolismo , Átrios do Coração/fisiopatologia , Sistema de Condução Cardíaco/metabolismo , Sistema de Condução Cardíaco/fisiopatologia , Frequência Cardíaca , Ventrículos do Coração/metabolismo , Ventrículos do Coração/fisiopatologia , Heterozigoto , Homozigoto , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Contração Miocárdica , Fenótipo , Função Ventricular
9.
Haemophilia ; 24(5): 815-822, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30112856

RESUMO

INTRODUCTION: The thrombin generation assay (TGA) can be used to monitor factor replacement therapy in patients with haemophilia. The TGA assay is typically performed using tissue factor as the reaction activator; however, activating with FIXa or FXIa can enhance assay sensitivity when FVIII < 1%. AIMS: To evaluate the sensitivity of the TGA when FIXa (5 nmol/L) and FXIa (0.22 nmol/L) are used to activate the assay in platelet-poor plasma and to compare these data to the one-stage and chromogenic assays. METHODS: Plasma from 10 severe FVIII-deficient subjects was supplemented with FVIII (0%, 0.1%, 0.4%, 1.2%, 4%, 11% and 33%), using either Novo Eight® , Advate® , Eloctate® , turoctocog alfa pegol or a control standard. The one-stage and chromogenic assays quantified the FVIII levels. The TGA assay was activated using either FIXa or FXIa. RESULTS: Both FIXa- and FXIa-activated TGA were sensitive across FVIII concentrations, with intra-assay coefficient of variation (CV) < 10%. The FXIa-activated assay had 25% CV at the lowest level of FVIII compared to 10% CV with FIXa activation. There were strong correlations between the FIXa- and FXIa-activated TGA tests (R2  = 0.9912) and between the one-stage and chromogenic assays (R2  = 0.9469). However, there were poor relationships between the TGA tests and one-stage and chromogenic assays. CONCLUSIONS: Both FIXa- and FXIa activation results in similar TGA profiles across a FVIII range of 0.1%-33%; however, FIXa activation was more robust at the lowest levels of FVIII compared with FXIa activation.


Assuntos
Fator VIII/metabolismo , Fator XIa/metabolismo , Hemofilia A/sangue , Trombina/metabolismo , Humanos
10.
Nano Lett ; 16(12): 7551-7564, 2016 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-27960515

RESUMO

The ability to track labeled cancer cells in vivo would allow researchers to study their distribution, growth, and metastatic potential within the intact organism. Magnetic resonance (MR) imaging is invaluable for tracking cancer cells in vivo as it benefits from high spatial resolution and the absence of ionizing radiation. However, many MR contrast agents (CAs) required to label cells either do not significantly accumulate in cells or are not biologically compatible for translational studies. We have developed carbon-based nanodiamond-gadolinium(III) aggregates (NDG) for MR imaging that demonstrated remarkable properties for cell tracking in vivo. First, NDG had high relaxivity independent of field strength, a finding unprecedented for gadolinium(III) [Gd(III)]-nanoparticle conjugates. Second, NDG demonstrated a 300-fold increase in the cellular delivery of Gd(III) compared to that of clinical Gd(III) chelates without sacrificing biocompatibility. Further, we were able to monitor the tumor growth of NDG-labeled flank tumors by T1- and T2-weighted MR imaging for 26 days in vivo, longer than was reported for other MR CAs or nuclear agents. Finally, by utilizing quantitative maps of relaxation times, we were able to describe tumor morphology and heterogeneity (corroborated by histological analysis), which would not be possible with competing molecular imaging modalities.


Assuntos
Gadolínio , Imagem Molecular , Nanodiamantes , Neoplasias Experimentais/diagnóstico por imagem , Animais , Meios de Contraste , Feminino , Imageamento por Ressonância Magnética , Camundongos , Camundongos SCID
11.
J Am Chem Soc ; 137(28): 9108-16, 2015 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-26083313

RESUMO

Multiple imaging modalities are often required for in vivo imaging applications that require both high probe sensitivity and excellent spatial and temporal resolution. In particular, MR and optical imaging are an attractive combination that can be used to determine both molecular and anatomical information. Herein, we describe the synthesis and in vivo testing of two multimeric NIR-MR contrast agents that contain three Gd(III) chelates and an IR-783 dye moiety. One agent contains a PEG linker and the other a short alkyl linker. These agents label cells with extraordinary efficacy and can be detected in vivo using both imaging modalities. Biodistribution of the PEGylated agent shows observable fluorescence in xenograft MCF7 tumors and renal clearance by MR imaging.


Assuntos
Quelantes/química , Corantes/química , Meios de Contraste/química , Gadolínio/química , Imageamento por Ressonância Magnética , Imagem Multimodal , Imagem Óptica , Animais , Quelantes/síntese química , Quelantes/farmacocinética , Corantes/síntese química , Corantes/farmacocinética , Meios de Contraste/síntese química , Meios de Contraste/farmacocinética , Feminino , Gadolínio/farmacocinética , Humanos , Raios Infravermelhos , Células MCF-7 , Camundongos Nus , Neoplasias/diagnóstico , Distribuição Tecidual
12.
Arthritis Rheum ; 65(9): 2279-89, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23740612

RESUMO

OBJECTIVE: The ability to noninvasively monitor the development of inflammatory arthritis longitudinally has become increasingly important in experimental rheumatology. Magnetic resonance imaging (MRI) allows for detailed examination of anatomic structures, as well as the assessment of joint and soft tissue inflammation. The aim of this study was to extend the use of MRI to include quantitative measurements of bone destruction in murine ankle joints. METHODS: Joint disease was measured serially using clinical, histologic, in vivo imaging system (IVIS), micro-computed tomography (micro-CT), and MRI techniques in mouse ankle joints, using the K/BxN serum transfer-induced acute arthritis and K/BxA(g7) chronic arthritis models. Ankle joint MRI was performed using a gradient-echo pulse sequence to evaluate bone destruction and a spin-echo sequence to evaluate inflammation (long T2 signal). RESULTS: Arthritic mice, as compared to control mice, demonstrated increased disease severity according to clinical, histologic, IVIS, and MRI measures. Following induction of arthritis, the majority of volume expansion of the long T2 signal occurred in a juxtaarticular, rather than intrarticular, manner within the ankle joints. Bone destruction in K/BxA(g7) mouse ankle joints was readily detectible by MRI. Linear regression analyses demonstrated significant correlations between the clinical score and joint radiance intensity assessed by IVIS, between the ankle joint width and increased long T2 signal on MRI, and between the bone volume obtained by micro-CT and bone volume obtained by MRI. CONCLUSION: MRI is an optimal technology for anatomic localization of articular and soft tissue changes during the development and progression of inflammatory arthritis. Future studies may combine MRI with in vivo labeling agents to investigate joint disease in a cell type-specific manner.


Assuntos
Articulação do Tornozelo/patologia , Artrite Experimental/patologia , Reabsorção Óssea/patologia , Inflamação/patologia , Animais , Articulação do Tornozelo/diagnóstico por imagem , Artrite Experimental/diagnóstico por imagem , Reabsorção Óssea/diagnóstico por imagem , Progressão da Doença , Inflamação/diagnóstico por imagem , Imageamento por Ressonância Magnética , Camundongos , Radiografia
13.
J Environ Qual ; 43(3): 955-63, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-25602824

RESUMO

Denitrification is an anaerobic microbial process that transforms nitrate (NO) to nitrogen (N) gas, preventing the movement of NO into coastal waters where it can lead to eutrophication. Urbanization can reduce the potential for denitrification in riparian zones and streams by altering the environmental conditions that foster denitrification (i.e., low oxygen and available C). Here we evaluated the factors limiting denitrification potential in forested and herbaceous riparian and stream pool and organic debris dam habitats in urban, suburban, exurban, and forested reference watersheds in the Baltimore, Maryland metropolitan area. Denitrification potential (with and without C and NO additions) and microbial biomass C and N content, potential net N mineralization and nitrification, microbial respiration, and inorganic N pools were measured in summer (June) and fall (November). Denitrification potentials were highest in the herbaceous riparian soils and lowest in pool sediments. Forested riparian soil denitrification potential was highest in the exurban watershed but in other habitats did not vary with watershed type. Nearly all variables were higher in June than in November. Overall, C was a more important driver of denitrification potential than N; potentials in unamended and N-amended treatments were very similar (<200 ng N g h) and were much lower than in the C-amended and C+N-amended treatments (>800 ng N g h). Our results suggest that efforts to enhance denitrification in urban watersheds need to focus on the differential controls of denitrification across habitats, urban land use types, and seasons.

14.
PLoS One ; 19(9): e0310551, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39298449

RESUMO

BACKGROUND: The pathology in Duchenne muscular dystrophy (DMD) is characterized by degenerating muscle fibers, inflammation, fibro-fatty infiltrate, and edema, and these pathological processes replace normal healthy muscle tissue. The mdx mouse model is one of the most commonly used preclinical models to study DMD. Mounting evidence has emerged illustrating that muscle disease progression varies considerably in mdx mice, with inter-animal differences as well as intra-muscular differences in pathology in individual mdx mice. This variation is important to consider when conducting assessments of drug efficacy and in longitudinal studies. We developed a magnetic resonance imaging (MRI) segmentation and analysis pipeline to rapidly and non-invasively measure the severity of muscle disease in mdx mice. METHODS: Wildtype and mdx mice were imaged with MRI and T2 maps were obtained axially across the hindlimbs. A neural network was trained to rapidly and semi-automatically segment the muscle tissue, and the distribution of resulting T2 values was analyzed. Interdecile range and Pearson Skew were identified as biomarkers to quickly and accurately estimate muscle disease severity in mice. RESULTS: The semiautomated segmentation tool reduced image processing time approximately tenfold. Measures of Pearson skew and interdecile range based on that segmentation were repeatable and reflected muscle disease severity in healthy wildtype and diseased mdx mice based on both qualitative observation of images and correlation with Evans blue dye uptake. CONCLUSION: Use of this rapid, non-invasive, semi-automated MR image segmentation and analysis pipeline has the potential to transform preclinical studies, allowing for pre-screening of dystrophic mice prior to study enrollment to ensure more uniform muscle disease pathology across treatment groups, improving study outcomes.


Assuntos
Biomarcadores , Modelos Animais de Doenças , Imageamento por Ressonância Magnética , Camundongos Endogâmicos mdx , Músculo Esquelético , Distrofia Muscular de Duchenne , Animais , Imageamento por Ressonância Magnética/métodos , Camundongos , Distrofia Muscular de Duchenne/diagnóstico por imagem , Distrofia Muscular de Duchenne/patologia , Distrofia Muscular de Duchenne/metabolismo , Biomarcadores/metabolismo , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/metabolismo , Músculo Esquelético/patologia , Fenótipo , Índice de Gravidade de Doença , Masculino , Camundongos Endogâmicos C57BL , Processamento de Imagem Assistida por Computador
15.
Eur Urol Oncol ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39095299

RESUMO

BACKGROUND AND OBJECTIVE: The source of tissue for genomic profiling of metastatic castration-resistant prostate cancer (mCRPC) is often limited to osseous metastases. To guide patient management, metastatic site selection and the technique for targeted bone biopsies are critical for identifying deleterious gene mutations. Our objective was to identify key parameters associated with successful large-panel DNA sequencing. METHODS: We analyzed parameters for 243 men with progressing mCRPC who underwent 269 bone biopsies for genomic profiling between 2014 and 2018. Univariate and multivariate analyses were performed for clinical, imaging (bone scan; fluorodeoxyglucose [FDG] positron emission tomography [PET]; computed tomography [CT]; magnetic resonance imaging), and technical (biopsy site, number of samples, needle gauge) features associated with successful genomic profiling. KEY FINDINGS AND LIMITATIONS: Overall, 159 of 269 biopsies (59%) generated sufficient tumor material for a genomic profile. Seventy (26%) of the failures were histopathologically negative for mCRPC and 40 (15%) had insufficient tumor for genomic profiling. Of 199 mCRPC samples submitted for molecular testing, 159 (80%) yielded a genomic profile. On univariate analysis, PSA, serum acid phosphatase, number of biopsy samples, FDG PET positivity, CT attenuation, and CT morphology were significantly associated with genomic profiling success. On multivariate analysis, higher FDG maximum standardized uptake value (odds ratio [OR] 7.51, 95% confidence interval [CI] 3.01-18.78; p < 0.001), higher number of biopsy samples (OR 4.73, 95% CI 1.49-15.02; p = 0.008), and lower mean CT attenuation (OR 0.4, 95% CI 0.18-0.89; p = 0.025) were significantly associated with sequencing success. CONCLUSIONS AND CLINICAL IMPLICATIONS: In patients with mCRPC, bone biopsies from sites with metabolic activity and lower CT attenuation are associated with higher success rates for genomic profiling via a large-panel DNA sequencing platform. PATIENT SUMMARY: We identified factors associated with successful genetic testing of bone tissue for patients with metastatic prostate cancer. Our findings may help in guiding the right scan technique and biopsy site for personalized treatment planning.

16.
Ann Rheum Dis ; 72(1): 89-95, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22736097

RESUMO

OBJECTIVES: Patients with rheumatoid arthritis (RA) have a reduced life expectancy due to increased cardiovascular disease. The lack of a suitable animal model resembling both RA and atherosclerosis has hindered studies demonstrating a direct link between systemic inflammation in RA and the development of atherosclerosis. Our objective was to overcome this barrier by generating an animal model (K/BxA(g7)) that spontaneously develops both RA-like disease and atherosclerosis. METHODS: Arthritis severity was evaluated using clinical indices and immunohistochemical staining of ankle joint specimens. Aortic atherosclerosis was delineated via Sudan IV staining and immunohistochemical analysis. Serum cholesterol and lipoprotein levels were measured using enzymatic assays. Serum levels of cytokines, chemokines and adipokines were determined by Luminex assays. RESULTS: K/BxA(g7) mice developed a destructive arthropathy followed by prominent aortic atherosclerosis. These animals also displayed dyslipidaemia, characterised by reduced serum levels of total cholesterol and high-density lipoprotein, and increased low-density lipoprotein (LDL)/vLDL compared with control mice. Further, there were higher levels of circulating inflammatory mediators, such as interleukin-6, sRANKL and CCL5 in atherosclerotic K/BxA(g7) mice compared with controls. Treatment with etanercept reduced arthritis and atherosclerosis development in K/BxA(g7) mice. CONCLUSIONS: K/BxA(g7) mice recapitulate the same sequence of events occurring in patients with RA, namely an erosive, inflammatory arthritis followed by atherosclerosis. These data suggest that the K/BxA(g7) mouse is a novel system for investigating the interplay between systemic inflammation occurring in RA and the development of atherosclerosis.


Assuntos
Artrite Reumatoide/complicações , Aterosclerose/complicações , Modelos Animais de Doenças , Animais , Artrite Reumatoide/genética , Artrite Reumatoide/patologia , Aterosclerose/genética , Aterosclerose/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos
17.
Blood ; 117(20): 5514-22, 2011 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-21389323

RESUMO

Hemophilia A and B are caused by deficiencies in coagulation factor VIII (FVIII) and factor IX, respectively, resulting in deficient blood coagulation via the intrinsic pathway. The extrinsic coagulation pathway, mediated by factor VIIa and tissue factor (TF), remains intact but is negatively regulated by tissue factor pathway inhibitor (TFPI), which inhibits both factor VIIa and its product, factor Xa. This inhibition limits clot initiation via the extrinsic pathway, whereas factor deficiency in hemophilia limits clot propagation via the intrinsic pathway. ARC19499 is an aptamer that inhibits TFPI, thereby enabling clot initiation and propagation via the extrinsic pathway. The core aptamer binds tightly and specifically to TFPI. ARC19499 blocks TFPI inhibition of both factor Xa and the TF/factor VIIa complex. ARC19499 corrects thrombin generation in hemophilia A and B plasma and restores clotting in FVIII-neutralized whole blood. In the present study, using a monkey model of hemophilia, FVIII neutralization resulted in prolonged clotting times as measured by thromboelastography and prolonged saphenous-vein bleeding times, which are consistent with FVIII deficiency. ARC19499 restored thromboelastography clotting times to baseline levels and corrected bleeding times. These results demonstrate that ARC19499 inhibition of TFPI may be an effective alternative to current treatments of bleeding associated with hemophilia.


Assuntos
Aptâmeros de Nucleotídeos/farmacologia , Coagulação Sanguínea/efeitos dos fármacos , Hemostasia/efeitos dos fármacos , Lipoproteínas/antagonistas & inibidores , Animais , Aptâmeros de Nucleotídeos/química , Tempo de Sangramento , Modelos Animais de Doenças , Fator VIII/metabolismo , Fator VIIa/metabolismo , Fator Xa/metabolismo , Hemofilia A/sangue , Hemofilia A/tratamento farmacológico , Hemofilia B/sangue , Hemofilia B/tratamento farmacológico , Humanos , Técnicas In Vitro , Macaca fascicularis , Proteínas Recombinantes/antagonistas & inibidores , Trombina/biossíntese , Tromboplastina/metabolismo
18.
AIDS Behav ; 17(6): 2114-22, 2013 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22968397

RESUMO

Neonatal male circumcision (NMC) is an uncommon procedure in Southern Africa, but is being scaled up in Zambia for long-term HIV prevention. We conducted a cross-sectional survey on NMC with a convenience sample of mothers of newborn boys at two public clinics in Lusaka. Following the survey, mothers received information on availability of NMC, and uptake of the service was tracked. Predictors of uptake were assessed using bivariate and multivariate logistic regression. Of the 1,249 eligible mothers approached, 1000 (80%) agreed to participate. Although 97% of surveyed mothers said they definitely or probably planned to have their newborn son circumcised, only 11% of participants brought their newborn sons for NMC. Significant predictors of uptake in adjusted models included: Older maternal age (AOR 3.77, 95% CI 1.48-9.63 for age 36 and above compared to mothers age 25 and below), having attended antenatal care at an NMC site (AOR 2.13, 95% CI 1.32-3.44), older paternal age (AOR 4.36, 95% CI 1.28-14.91 for age 26-35 compared to fathers age 25 and below), and the infant's father being circumcised (AOR 2.21, 95% CI 1.35-3.62). While acceptability studies in Southern Africa have suggested strong support for MC among parents for having their sons circumcised, this may not translate to high uptake of newly-introduced NMC services.


Assuntos
Circuncisão Masculina/estatística & dados numéricos , Mães/psicologia , Adulto , Circuncisão Masculina/psicologia , Estudos Transversais , Feminino , Conhecimentos, Atitudes e Prática em Saúde , Humanos , Recém-Nascido , Modelos Logísticos , Masculino , Mães/estatística & dados numéricos , Cuidado Pós-Natal/psicologia , Cuidado Pós-Natal/estatística & dados numéricos , Adulto Jovem , Zâmbia/epidemiologia
19.
bioRxiv ; 2023 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-37293050

RESUMO

The pathology in Duchenne muscular dystrophy (DMD) is characterized by degenerating muscle fibers, inflammation, fibro-fatty infiltrate, and edema, and these pathological processes replace normal healthy muscle tissue. The mdx mouse model is one of the most commonly used preclinical models to study DMD. Mounting evidence has emerged illustrating that muscle disease progression varies considerably in mdx mice, with inter-animal differences as well as intra-muscular differences in pathology in individual mdx mice. This variation is important to consider when conducting assessments of drug efficacy and in longitudinal studies. Magnetic resonance imaging (MRI) is a non-invasive method that can be used qualitatively or quantitatively to measure muscle disease progression in the clinic and in preclinical models. Although MR imaging is highly sensitive, image acquisition and analysis can be time intensive. The purpose of this study was to develop a semi-automated muscle segmentation and quantitation pipeline that can quickly and accurately estimate muscle disease severity in mice. Herein, we show that the newly developed segmentation tool accurately divides muscle. We show that measures of skew and interdecile range based on segmentation sufficiently estimate muscle disease severity in healthy wildtype and diseased mdx mice. Moreover, the semi-automated pipeline reduced analysis time by nearly 10-fold. Use of this rapid, non-invasive, semi-automated MR imaging and analysis pipeline has the potential to transform preclinical studies, allowing for pre-screening of dystrophic mice prior to study enrollment to ensure more uniform muscle disease pathology across treatment groups, improving study outcomes.

20.
AIDS Care ; 24(1): 12-9, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-21711163

RESUMO

Neonatal male circumcision (NMC) is being scaled up in Zambia and elsewhere in Southern Africa as a long-term HIV prevention strategy. We conducted 12 focus group discussions with 129 parents and grandparents in Lusaka, recruited from two sites providing free NMC services and information about NMC, to explore the acceptability of circumcising newborn boys. Most participants recognized the benefits of circumcision for HIV prevention, and the advantages of circumcising their children and grandchildren at a young age. Fear of negative outcomes, concerns about pain, and issues around cultural identity may challenge NMC uptake. To effectively promote the service, the upper age limit for NMC must be emphasized, and fathers must be targeted by messaging campaigns.


Assuntos
Circuncisão Masculina/psicologia , Infecções por HIV/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Aceitação pelo Paciente de Cuidados de Saúde , Adolescente , Adulto , Feminino , Grupos Focais , Humanos , Recém-Nascido , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Adulto Jovem , Zâmbia
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