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1.
Cell ; 156(3): 603-616, 2014 Jan 30.
Artículo en Inglés | MEDLINE | ID: mdl-24485463

RESUMEN

Glioblastomas (GBMs) are the most common and malignant primary brain tumors and are aggressively treated with surgery, chemotherapy, and radiotherapy. Despite this treatment, recurrence is inevitable and survival has improved minimally over the last 50 years. Recent studies have suggested that GBMs exhibit both heterogeneity and instability of differentiation states and varying sensitivities of these states to radiation. Here, we employed an iterative combined theoretical and experimental strategy that takes into account tumor cellular heterogeneity and dynamically acquired radioresistance to predict the effectiveness of different radiation schedules. Using this model, we identified two delivery schedules predicted to significantly improve efficacy by taking advantage of the dynamic instability of radioresistance. These schedules led to superior survival in mice. Our interdisciplinary approach may also be applicable to other human cancer types treated with radiotherapy and, hence, may lay the foundation for significantly increasing the effectiveness of a mainstay of oncologic therapy. PAPERCLIP:


Asunto(s)
Neoplasias Encefálicas/radioterapia , Glioblastoma/radioterapia , Dosis de Radiación , Animales , Neoplasias Encefálicas/patología , Glioblastoma/patología , Humanos , Ratones , Modelos Biológicos
2.
Am J Gastroenterol ; 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38661148

RESUMEN

INTRODUCTION: Assessing the cumulative degree of bowel injury in ileal Crohn's disease (CD) is difficult. We aimed to develop machine learning (ML) methodologies for automated estimation of cumulative ileal injury on computed tomography-enterography (CTE) to help predict future bowel surgery. METHODS: Adults with ileal CD using biologic therapy at a tertiary care center underwent ML analysis of CTE scans. Two fellowship-trained radiologists graded bowel injury severity at granular spatial increments along the ileum (1 cm), called mini-segments. ML segmentation methods were trained on radiologist grading with predicted severity and then spatially mapped to the ileum. Cumulative injury was calculated as the sum (S-CIDSS) and mean of severity grades along the ileum. Multivariate models of future small bowel resection were compared with cumulative ileum injury metrics and traditional bowel measures, adjusting for laboratory values, medications, and prior surgery at the time of CTE. RESULTS: In 229 CTE scans, 8,424 mini-segments underwent analysis. Agreement between ML and radiologists injury grading was strong (κ = 0.80, 95% confidence interval 0.79-0.81) and similar to inter-radiologist agreement (κ = 0.87, 95% confidence interval 0.85-0.88). S-CIDSS (46.6 vs 30.4, P = 0.0007) and mean cumulative injury grade scores (1.80 vs 1.42, P < 0.0001) were greater in CD biologic users that went to future surgery. Models using cumulative spatial metrics (area under the curve = 0.76) outperformed models using conventional bowel measures, laboratory values, and medical history (area under the curve = 0.62) for predicting future surgery in biologic users. DISCUSSION: Automated cumulative ileal injury scores show promise for improving prediction of outcomes in small bowel CD. Beyond replicating expert judgment, spatial enterography analysis can augment the personalization of bowel assessment in CD.

3.
Nat Methods ; 18(6): 669-677, 2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34059826

RESUMEN

Single-molecule localization microscopy (SMLM) relies on the blinking behavior of a fluorophore, which is the stochastic switching between fluorescent and dark states. Blinking creates multiple localizations belonging to the same fluorophore, confounding quantitative analyses and interpretations. Here we present a method, termed distance distribution correction (DDC), to eliminate blinking-caused repeat localizations without any additional calibrations. The approach relies on obtaining the true pairwise distance distribution of different fluorophores naturally from the imaging sequence by using distances between localizations separated by a time much longer than the average fluorescence survival time. We show that, using the true pairwise distribution, we can define and maximize the likelihood, obtaining a set of localizations void of blinking artifacts. DDC results in drastic improvements in obtaining the closest estimate of the true spatial organization and number of fluorescent emitters in a wide range of applications, enabling accurate reconstruction and quantification of SMLM images.


Asunto(s)
Algoritmos , Microscopía Fluorescente/métodos , Imagen Individual de Molécula/métodos , Artefactos , Colorantes Fluorescentes/química , Procesos Estocásticos
4.
Magn Reson Med ; 91(6): 2568-2578, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38265182

RESUMEN

PURPOSE: Analyzing bone marrow in the hematologic cancer myelofibrosis requires endpoint histology in mouse models and bone marrow biopsies in patients. These methods hinder the ability to monitor therapy over time. Preclinical studies typically begin treatment before mice develop myelofibrosis, unlike patients who begin therapy only after onset of disease. Using clinically relevant, quantitative MRI metrics allowed us to evaluate treatment in mice with established myelofibrosis. METHODS: We used chemical shift-encoded fat imaging, DWI, and magnetization transfer sequences to quantify bone marrow fat, cellularity, and macromolecular components in a mouse model of myelofibrosis. We monitored spleen volume, the established imaging marker for treatment, with anatomic MRI. After confirming bone marrow disease by MRI, we randomized mice to treatment with an approved drug (ruxolitinib or fedratinib) or an investigational agent, navitoclax, for 33 days. We measured the effects of therapy over time with bone marrow and spleen MRI. RESULTS: All treatments produced heterogeneous responses with improvements in bone marrow evident in subsets of individual mice in all treatment groups. Reductions in spleen volume commonly occurred without corresponding improvement in bone marrow. MRI revealed patterns associated with effective and ineffective responses to treatment in bone marrow and identified regional variations in efficacy within a bone. CONCLUSIONS: Quantitative MRI revealed modest, heterogeneous improvements in bone marrow disease when treating mice with established myelofibrosis. These results emphasize the value of bone marrow MRI to assess treatment in preclinical models and the potential to advance clinical trials for patients.


Asunto(s)
Médula Ósea , Mielofibrosis Primaria , Animales , Ratones , Médula Ósea/diagnóstico por imagen , Médula Ósea/patología , Imagen por Resonancia Magnética , Mielofibrosis Primaria/diagnóstico por imagen , Mielofibrosis Primaria/tratamiento farmacológico , Mielofibrosis Primaria/patología , Bazo/diagnóstico por imagen
5.
Rural Remote Health ; 24(2): 8725, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38909989

RESUMEN

INTRODUCTION: The Northern Ontario School of Medicine University seeks to address rural physician shortages in Northern Ontario. One key strategy the school employs is the use of experiential learning placements embedded throughout its undergraduate curriculum. In second year, students embark on two 4-week placements in rural and remote communities. This study sought to explore the factors that contribute to a positive learning experience from the preceptor's perspective. METHODS: Semi-structured interviews were conducted with five community preceptors who have participated in these placements. Using the information from these interviews a survey was created and sent to another 15 preceptors. Data were analyzed using qualitative methods and frequencies. RESULTS: Three key themes were identified from both the interviews and survey data: the role of early rural and remote placements; the risks of these placements; and the need for a reciprocal relationship between institutions, preceptors, and students to create a positive learning environment. CONCLUSION: Preceptors value the opportunity to teach students, but the aims of these placements are not clear and preceptors and local hospitals need more workforce resources to make these experiences positive.


Asunto(s)
Preceptoría , Servicios de Salud Rural , Humanos , Preceptoría/organización & administración , Servicios de Salud Rural/organización & administración , Ontario , Entrevistas como Asunto , Educación de Pregrado en Medicina/organización & administración , Estudiantes de Medicina/psicología , Estudiantes de Medicina/estadística & datos numéricos , Área sin Atención Médica
6.
Med Teach ; 45(4): 404-411, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36288735

RESUMEN

BACKGROUND: In an arts integrated interdisciplinary study set to investigate ways to improve social accountability (SA) in medical education, our research team has established a renewed understanding of compassion in the current SA movement. AIM: This paper explores the co-evolution of compassion and SA. METHODS: The study used an arts integrated approach to investigate people's perceptions of SA in four medical schools across Australia, Canada, and the USA. Each school engaged approximately 25 participants who partook in workshops and in-depth interviews. RESULTS: We began with a study of SA and the topic of compassion emerged out of our qualitative data and biweekly meetings within the research team. Content analysis of the data and pedagogical discussion brought us to realize the importance of compassion in the practice of SA. CONCLUSIONS: The cultivation of compassion needs to play a significant role in a socially accountable medical educational system. Medical schools as educational institutions may operate themselves with compassion as a driving force in engaging partnership with students and communities. Social accountability without compassion is not SA; compassion humanizes institutional policy by engaging sympathy and care.


Asunto(s)
Educación Médica , Empatía , Humanos , Responsabilidad Social , Australia , Canadá
7.
Eur J Immunol ; 51(10): 2441-2451, 2021 10.
Artículo en Inglés | MEDLINE | ID: mdl-34287839

RESUMEN

Inhibition of the BCL6 BTB domain results in killing Diffuse Large B-cell Lymphoma (DLBL) cells, reducing the T-cell dependent germinal center (GC) reaction in mice, and reversing GC hyperplasia in nonhuman primates. The available BCL6 BTB-specific inhibitors are poorly water soluble, thus, limiting their absorption in vivo and our understanding of therapeutic strategy targeting GC. We synthesized a prodrug (AP-4-287) from a potent BCL6 BTB inhibitor (FX1) with improved aqueous solubility and pharmacokinetics (PK) in mice. We also evaluated its in vivo biological activity on humoral immune responses using the sheep red blood cells (SRBC)-vaccination mouse model. AP-4-287 had a significant higher aqueous solubility and was readily converted to FX1 in vivo after intraperitoneally (i.p.) administration, but a shorter half-life in vivo. Importantly, AP-4-287 treatment led to a reversible effect on (1) the reduction in the frequency of splenic Ki67+ CD4+ T cells, Tfh cells, and GC B cells; (2) lower GC formation following vaccination; and (3) a decrease in the titers of antigen-specific IgG and IgM antibodies. Our study advances the preclinical development of drug targeting BCL6 BTB domain for the treatment of diseases that are associated with abnormal BCL6 elevation.


Asunto(s)
Activación de Linfocitos/efectos de los fármacos , Activación de Linfocitos/inmunología , Dominios y Motivos de Interacción de Proteínas/efectos de los fármacos , Proteínas Proto-Oncogénicas c-bcl-6/antagonistas & inhibidores , Linfocitos T/efectos de los fármacos , Linfocitos T/inmunología , Linfocitos T/metabolismo , Animales , Formación de Anticuerpos/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Diferenciación Celular/inmunología , Técnicas de Química Sintética , Centro Germinal/efectos de los fármacos , Centro Germinal/inmunología , Centro Germinal/metabolismo , Inmunidad Humoral/efectos de los fármacos , Inmunomodulación/efectos de los fármacos , Indoles/administración & dosificación , Indoles/síntesis química , Indoles/farmacocinética , Ratones , Profármacos/administración & dosificación , Profármacos/síntesis química , Profármacos/farmacocinética , Proteínas Proto-Oncogénicas c-bcl-6/química , Proteínas Proto-Oncogénicas c-bcl-6/metabolismo , Subgrupos de Linfocitos T/efectos de los fármacos , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Tiazolidinedionas/administración & dosificación , Tiazolidinedionas/síntesis química , Tiazolidinedionas/farmacocinética
8.
Radiology ; 302(1): 218-225, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34665030

RESUMEN

Background Aortic diameter measurements in patients with a thoracic aortic aneurysm (TAA) show wide variation. There is no technique to quantify aortic growth in a three-dimensional (3D) manner. Purpose To validate a CT-based technique for quantification of 3D growth based on deformable registration in patients with TAA. Materials and Methods Patients with ascending and descending TAA with two or more CT angiography studies between 2006 and 2020 were retrospectively identified. The 3D aortic growth was quantified using vascular deformation mapping (VDM), a technique that uses deformable registration to warp a mesh constructed from baseline aortic anatomy. Growth assessments between VDM and clinical CT diameter measurements were compared. Aortic growth was quantified as the ratio of change in surface area at each mesh element (area ratio). Manual segmentations were performed by independent raters to assess interrater reproducibility. Registration error was assessed using manually placed landmarks. Agreement between VDM and clinical diameter measurements was assessed using Pearson correlation and Cohen κ coefficients. Results A total of 38 patients (68 surveillance intervals) were evaluated (mean age, 69 years ± 9 [standard deviation]; 21 women), with TAA involving the ascending aorta (n = 26), descending aorta (n = 10), or both (n = 2). VDM was technically successful in 35 of 38 (92%) patients and 58 of 68 intervals (85%). Median registration error was 0.77 mm (interquartile range, 0.54-1.10 mm). Interrater agreement was high for aortic segmentation (Dice similarity coefficient = 0.97 ± 0.02) and VDM-derived area ratio (bias = 0.0, limits of agreement: -0.03 to 0.03). There was strong agreement (r = 0.85, P < .001) between peak area ratio values and diameter change. VDM detected growth in 14 of 58 (24%) intervals. VDM revealed growth outside the maximally dilated segment in six of 14 (36%) growth intervals, none of which were detected with diameter measurements. Conclusion Vascular deformation mapping provided reliable and comprehensive quantitative assessment of three-dimensional aortic growth and growth patterns in patients with thoracic aortic aneurysms undergoing CT surveillance. Published under a CC BY 4.0 license Online supplemental material is available for this article. See also the editorial by Wieben in this issue.


Asunto(s)
Aneurisma de la Aorta Torácica/diagnóstico por imagen , Aneurisma de la Aorta Torácica/patología , Angiografía por Tomografía Computarizada/métodos , Imagenología Tridimensional/métodos , Anciano , Aorta Torácica/diagnóstico por imagen , Aorta Torácica/patología , Femenino , Humanos , Masculino , Reproducibilidad de los Resultados , Estudios Retrospectivos
9.
J Viral Hepat ; 29(2): 147-155, 2022 02.
Artículo en Inglés | MEDLINE | ID: mdl-34773341

RESUMEN

Hepatitis C is a leading cause of liver disease and transplantation and is a significant burden on public health worldwide. This study aimed to apply the Electronic Nose (E-Nose) and quadrupole Mass Spectrometry (MS/MS) technologies for screening blood samples from hepatitis C patients and healthy controls. We analysed volatile organic compounds (VOCs) in the headspace over blood samples to identify those VOCs characteristic for diagnosing hepatitis C patients. The study comprised 150 acute hepatitis C patients with age range: 24-59 years, and mean age ±SD: 41.5 ± 12.8 years and 150 age-matched healthy controls (age range: 24-51 and mean age: 40.11 ± 4.89 years) from the Hospital of the Medical Research Institute, Alexandria University, Alexandria, Egypt. Collected blood samples were analysed qualitatively and quantitatively using the E-Nose and MS/MS techniques, respectively. Principal component analysis of the E-Nose 10-sensor responses accurately classified blood samples from hepatitis C patients and healthy controls. The first two principal components explained over 98.35% of the variance in signals with no false-positive (healthy controls) or false-negative (hepatitis C patients) results. MS/MS showed two fragmentation ions at m/z of 104 and 151 Da with the positive electrospray ionization mode (ESI+) in blood samples for hepatitis C patients, but not for healthy controls or background water samples. We identified the two specific fragmentation ions at m/z 104 and m/z 151 Da as malonic acid (MF: C3 H4 O4 ; MW: 104.06 g/mol) and monosaccharide pentose (MF: C5 H10 O5 ; MW: 150.13 g/mol) in VOCs of the headspace over blood samples for hepatitis C patients. This provides a rationale for developing diagnostic tests for hepatitis C virus based on altered trace VOCs concentrations using the relatively inexpensive, easy-to-use, portable and non-invasive E-Nose technology.


Asunto(s)
Hepatitis C , Hepatitis Viral Humana , Compuestos Orgánicos Volátiles , Adulto , Nariz Electrónica , Hepatitis C/diagnóstico , Humanos , Persona de Mediana Edad , Espectrometría de Masas en Tándem , Adulto Joven
10.
Int J Audiol ; 61(8): 621-631, 2022 08.
Artículo en Inglés | MEDLINE | ID: mdl-34622731

RESUMEN

Objective: This exploratory Phase 2 clinical trial is the first determining safety and efficacy of oral D-methionine (D-met) in reducing cisplatin-induced ototoxicity.Design: Randomised parallel double-blind placebo-controlled exploratory Phase 2 study.Study samples: Fifty adult cancer patients received oral D-met or placebo before each cisplatin dose. Physical examination, blood collection and audiometry occurred at baseline and subsequent visits plus post-treatment audiometry. After attrition, final analysis included 27 patients.Results: Significant treatment group by ear and time (baseline vs. post-treatment) interactions occurred at 10 kHz and 11.2 kHz. Placebo and D-met groups differed in threshold shift for left ear at 11.2 kHz (mean difference = 22.97 dB [9.59, 36.35]). Averaging across ears, placebo group showed significant threshold shifts from baseline to post-treatment at 10 kHz (mean shift= -13.65 dB [-21.32,-5.98]), 11.2 kHz (-16.15 dB [-25.19,-7.12]), and 12.5 kHz (-11.46 dB [-19.18,-3.74]) but not 8 kHz (-8.65 dB [-17.86, 0.55]). The D-met group showed no significant threshold shifts (8 kHz: -1.25 dB [-7.75, 5.25]; 10 kHz:-3.93 dB [-8.89, 1.03]; 11.2 kHz:-4.82 dB [-11.21, 1.57]; 12.5 kHz:-3.68 dB [-11.57, 4.21]). Side effects did not significantly differ between groups.Conclusion: Oral D-met reduces cisplatin-induced ototoxicity in humans.


Asunto(s)
Pérdida Auditiva , Metionina , Adulto , Umbral Auditivo , Cisplatino/toxicidad , Pérdida Auditiva/inducido químicamente , Pérdida Auditiva/diagnóstico , Pérdida Auditiva/prevención & control , Humanos , India , Metionina/uso terapéutico , Ototoxicidad/prevención & control
11.
Int J Health Plann Manage ; 37 Suppl 1: 59-78, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-35986520

RESUMEN

Health care and academic institutions are increasingly committing to social accountability, a strategic shift that requires priorities, activities, and evaluations to be co-determined with all relevant partners. Consequently, governments, accreditors, funders, and communities are calling for these institutions to communicate their progress towards social accountability. The purpose of this study was to develop a conceptual framework around a socially accountable learning health system. This article presents an integrated analysis of two studies: (i) a narrative review of 11 prominent social accountability and health services conceptual frameworks and (ii) a reflexive thematic analysis of 18 key informant interviews. Using a systematic conceptual framework development and integrated theory of change/realist evaluation methodologies, we describe a synthesis of these findings to develop a conceptual framework for describing and evaluating socially accountable health professional education. The resulting framework describes assessment phases of social accountability, transitions between phases, learning cycles, and the actors and systems that collectively mobilise social accountability at multiple levels in health and education systems. The framework can be used to evaluate interventions or characterise progress towards social accountability in different settings, as illustrated in the example at the end of the paper. The framework emphasises the significance of designing, mobilising, and evaluating social accountability as part of a contextualised learning health system.


Asunto(s)
Educación Médica , Aprendizaje del Sistema de Salud , Humanos , Aprendizaje , Responsabilidad Social , Población Rural
12.
Clin Infect Dis ; 72(3): 495-498, 2021 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-33527127

RESUMEN

Accurate characterization of the human immunodeficiency virus (HIV) reservoir is imperative to develop an effective cure. HIV was measured in antiretroviral therapy-suppressed individuals using the intact proviral DNA assay (IPDA), along with assays for total or integrated HIV DNA, and inducible HIV RNA or p24. Intact provirus correlated with total and integrated HIV.


Asunto(s)
Infecciones por VIH , VIH-1 , Linfocitos T CD4-Positivos , ADN Viral/genética , Infecciones por VIH/tratamiento farmacológico , VIH-1/genética , Humanos , Provirus/genética , Latencia del Virus
13.
Bioconjug Chem ; 32(10): 2195-2204, 2021 10 20.
Artículo en Inglés | MEDLINE | ID: mdl-34591471

RESUMEN

Nanoscale metal-organic frameworks (nMOFs) are a unique type of hybrid materials, which are broadly applicable as cargo delivery systems. However, the relatively low material stability and insufficient cancer cell interacting capacity have limited nMOFs' applications in cancer theranostics. Herein, a zirconium-based nMOF UiO-66-N3 was synthesized, and its surface was covalently functionalized with alkyne-containing polyethylene glycol (PEG) via the azide-alkyne click chemistry. After that, F3 peptide was attached for targeting of cancer cells (the material was denoted as UiO-66-PEG-F3). Doxorubicin (DOX) served as a therapeutic drug and a fluorescent label in this study, and it was transported into UiO-66-PEG conjugates with sufficient drug loading efficiency. pH-responsive release of DOX from UiO-66 conjugates was witnessed. The structural integrity of UiO-66-N3 was maintained post the surface modification process. Flow cytometry and confocal fluorescence microscopy revealed that DOX/UiO-66-PEG-F3 had stronger accumulation in MDA-MB-231 cells (nucleolin+) compared with DOX/UiO-66-PEG. In order to track the pharmacokinetic behavior (organ distribution profile) in vivo, the positron-emitting zirconium-89 (89Zr) was incorporated into UiO-66-N3. Similar PEGylation and F3 peptide conjugation resulted in the formation of 89Zr-UiO-66-PEG-F3. Serial positron emission tomography (PET) imaging demonstrated that the preferential accumulation of 89Zr-UiO-66-PEG-F3 in MDA-MB-231 tumors, and their liver clearance was faster than PEGylated UiO-66 using noncovalent methods. Thus, the PEGylated nMOFs using covalent strategies may find broad application in future cancer theranostics.


Asunto(s)
Portadores de Fármacos , Estructuras Metalorgánicas
14.
Mol Pharm ; 18(4): 1690-1698, 2021 04 05.
Artículo en Inglés | MEDLINE | ID: mdl-33734721

RESUMEN

The urokinase plasminogen activator (uPA) and its cofactors are important regulators of tumor initiation and progression (including metastasis), and its overexpression is associated with unfavorable situations in cancer patients. We have previously used positron emission tomography (PET) imaging with a radiolabeled monoclonal antibody against the uPA (named ATN-291) to detect the uPA signaling activity in various cancer types; however, good tumor contrast can only be observed 24 h postinjection. To shorten the antibody circulation time and decrease interactions of ATN-291 with the mononuclear phagocyte system (MPS), our goal in this study is to develop an engineered antibody fragment (F(ab')2) from the parent antibody. By pepsin digestion and chromatography purification, ATN-291 F(ab')2 was obtained and characterized. Subsequently, it was conjugated with NOTA-Bn-NCS or fluorescein isothiocyanate (FITC) for PET imaging and fluorescence-mediated cellular analysis (i.e., flow cytometry or fluorescence microscopy). We confirmed that ATN-291 F(ab')2 still maintained a good targeting efficacy for the uPA in MDA-MB-231 cells (uPA+) and it had a faster blood clearance speed compared with ATN-291, while its interaction with MPS has been significantly decreased. In rodent tumor xenografts, radiolabeled ATN-291 F(ab')2 had a selective and persistent uptake in MDA-MB-231 tumors, with an early tumor-to-blood ratio of 1.3 ± 0.8 (n = 4) at 2 h postinjection from PET imaging. During our observation, radiolabeled ATN-291 F(ab')2 was excreted from both renal and hepatobiliary pathways. Radiolabeled ATN-291 F(ab')2 was also used for detecting uPA fluctuation during the tumor treatment in test animals. We concluded that radiolabeled ATN-291 F(ab')2 could be used as fast as PET cancer diagnostics with versatile applicability.


Asunto(s)
Anticuerpos Monoclonales/administración & dosificación , Fragmentos Fab de Inmunoglobulinas/administración & dosificación , Proteínas de la Membrana/antagonistas & inhibidores , Tomografía de Emisión de Positrones/métodos , Neoplasias de la Mama Triple Negativas/diagnóstico , Animales , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/genética , Femenino , Fluoresceína-5-Isotiocianato/química , Humanos , Fragmentos Fab de Inmunoglobulinas/química , Fragmentos Fab de Inmunoglobulinas/genética , Proteínas de la Membrana/metabolismo , Ratones , Ingeniería de Proteínas , Neoplasias de la Mama Triple Negativas/patología , Ensayos Antitumor por Modelo de Xenoinjerto
15.
J Immunol ; 203(3): 705-717, 2019 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-31253727

RESUMEN

We previously reported that pegylated IFN-α2a (Peg-IFN-α2a) added to antiretroviral therapy (ART)-suppressed, HIV-infected subjects resulted in plasma HIV control and integrated HIV DNA decrease. We now evaluated whether innate NK cell activity or PBMC transcriptional profiles were associated with decreases in HIV measures. Human peripheral blood was analyzed prior to Peg-IFN-α2a administration (ART, baseline), after 5 wk of ART+Peg-IFN-α2a, and after 12 wk of Peg-IFN-α2a monotherapy (primary endpoint). After 5 wk of ART+Peg-IFN-α2a, immune subset frequencies were preserved, and induction of IFN-stimulated genes was noted in all subjects except for a subset in which the lack of IFN-stimulated gene induction was associated with increased expression of microRNAs. Viral control during Peg-IFN-α2a monotherapy was associated with 1) higher levels of NK cell activity and IFN-γ-induced protein 10 (IP-10) on ART (preimmunotherapy) and 2) downmodulation of NK cell KIR2DL1 and KIR2DL2/DL3 expression, transcriptional enrichment of expression of genes associated with NK cells in HIV controller subjects, and higher ex vivo IFN-α-induced NK cytotoxicity after 5 wk of ART+Peg-IFN-α2a. Integrated HIV DNA decline after immunotherapy was also associated with gene expression patterns indicative of cell-mediated activation and NK cytotoxicity. Overall, an increase in innate activity and NK cell cytotoxicity were identified as correlates of Peg-IFN-α2a-mediated HIV control.


Asunto(s)
Terapia Antirretroviral Altamente Activa/métodos , Infecciones por VIH/tratamiento farmacológico , VIH-1/efectos de los fármacos , Interferón-alfa/uso terapéutico , Células Asesinas Naturales/inmunología , Polietilenglicoles/uso terapéutico , Células Cultivadas , Quimiocina CXCL10/metabolismo , Infecciones por VIH/inmunología , VIH-1/inmunología , Humanos , MicroARNs/biosíntesis , MicroARNs/genética , Receptores KIR2DL1/biosíntesis , Receptores KIR2DL2/biosíntesis , Proteínas Recombinantes/uso terapéutico
16.
Breast Cancer Res ; 22(1): 60, 2020 06 05.
Artículo en Inglés | MEDLINE | ID: mdl-32503622

RESUMEN

BACKGROUND: Mitochondrial dynamics underlies malignant transformation, cancer progression, and response to treatment. Current research presents conflicting evidence for functions of mitochondrial fission and fusion in tumor progression. Here, we investigated how mitochondrial fission and fusion states regulate underlying processes of cancer progression and metastasis in triple-negative breast cancer (TNBC). METHODS: We enforced mitochondrial fission and fusion states through chemical or genetic approaches and measured migration and invasion of TNBC cells in 2D and 3D in vitro models. We also utilized kinase translocation reporters (KTRs) to identify single cell effects of mitochondrial state on signaling cascades, PI3K/Akt/mTOR and Ras/Raf/MEK/ERK, commonly activated in TNBC. Furthermore, we determined effects of fission and fusion states on metastasis, bone destruction, and signaling in mouse models of breast cancer. RESULTS: Enforcing mitochondrial fission through chemical or genetic approaches inhibited migration, invasion, and metastasis in TNBC. Breast cancer cells with predominantly fissioned mitochondria exhibited reduced activation of Akt and ERK both in vitro and in mouse models of breast cancer. Treatment with leflunomide, a potent activator of mitochondrial fusion proteins, overcame inhibitory effects of fission on migration, signaling, and metastasis. Mining existing datasets for breast cancer revealed that increased expression of genes associated with mitochondrial fission correlated with improved survival in human breast cancer. CONCLUSIONS: In TNBC, mitochondrial fission inhibits cellular processes and signaling pathways associated with cancer progression and metastasis. These data suggest that therapies driving mitochondrial fission may benefit patients with breast cancer.


Asunto(s)
Transformación Celular Neoplásica/efectos de los fármacos , Mitocondrias/efectos de los fármacos , Dinámicas Mitocondriales/fisiología , Neoplasias de la Mama Triple Negativas/metabolismo , Neoplasias de la Mama Triple Negativas/patología , Animales , Neoplasias Óseas/tratamiento farmacológico , Neoplasias Óseas/metabolismo , Neoplasias Óseas/secundario , Carboxiliasas/genética , Carboxiliasas/metabolismo , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Femenino , Humanos , Inmunosupresores/farmacología , Leflunamida/farmacología , Ratones , Ratones Endogámicos NOD , Ratones SCID , Mitocondrias/metabolismo , Mitocondrias/patología , Invasividad Neoplásica , Fosfatidilinositol 3-Quinasas/genética , Fosfatidilinositol 3-Quinasas/metabolismo , Pronóstico , Proteínas Proto-Oncogénicas c-akt/genética , Proteínas Proto-Oncogénicas c-akt/metabolismo , Serina-Treonina Quinasas TOR/genética , Serina-Treonina Quinasas TOR/metabolismo , Neoplasias de la Mama Triple Negativas/tratamiento farmacológico , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
17.
Nat Methods ; 14(4): 427-434, 2017 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-28288122

RESUMEN

Compartmentalized biochemical activities are essential to all cellular processes, but there is no generalizable method to visualize dynamic protein activities in living cells at a resolution commensurate with cellular compartmentalization. Here, we introduce a new class of fluorescent biosensors that detect biochemical activities in living cells at a resolution up to threefold better than the diffraction limit. These 'FLINC' biosensors use binding-induced changes in protein fluorescence dynamics to translate kinase activities or protein-protein interactions into changes in fluorescence fluctuations, which are quantifiable through stochastic optical fluctuation imaging. A protein kinase A (PKA) biosensor allowed us to resolve minute PKA activity microdomains on the plasma membranes of living cells and to uncover the role of clustered anchoring proteins in organizing these activity microdomains. Together, these findings suggest that biochemical activities of the cell are spatially organized into an activity architecture whose structural and functional characteristics can be revealed by these new biosensors.


Asunto(s)
Técnicas Biosensibles/métodos , Proteínas Quinasas Dependientes de AMP Cíclico/metabolismo , Membrana Celular/metabolismo , Proteínas Quinasas Dependientes de AMP Cíclico/análisis , Escherichia coli/genética , Transferencia Resonante de Energía de Fluorescencia/métodos , Colorantes Fluorescentes , Proteínas Fluorescentes Verdes/metabolismo , Células HeLa , Humanos , Microscopía/instrumentación , Microscopía/métodos , Imagen Molecular/métodos , Mutagénesis Sitio-Dirigida , Mapeo de Interacción de Proteínas/métodos , Procesos Estocásticos
18.
Am J Respir Crit Care Med ; 200(5): 575-581, 2019 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-30794432

RESUMEN

Rationale: Evidence suggests damage to small airways is a key pathologic lesion in chronic obstructive pulmonary disease (COPD). Computed tomography densitometry has been demonstrated to identify emphysema, but no such studies have been performed linking an imaging metric to small airway abnormality.Objectives: To correlate ex vivo parametric response mapping (PRM) analysis to in vivo lung tissue measurements of patients with severe COPD treated by lung transplantation and control subjects.Methods: Resected lungs were inflated, frozen, and systematically sampled, generating 33 COPD (n = 11 subjects) and 22 control tissue samples (n = 3 subjects) for micro-computed tomography analysis of terminal bronchioles (TBs; last generation of conducting airways) and emphysema.Measurements and Main Results: PRM analysis was conducted to differentiate functional small airways disease (PRMfSAD) from emphysema (PRMEmph). In COPD lungs, TB numbers were reduced (P = 0.01); surviving TBs had increased wall area percentage (P < 0.001), decreased circularity (P < 0.001), reduced cross-sectional luminal area (P < 0.001), and greater airway obstruction (P = 0.008). COPD lungs had increased airspace size (P < 0.001) and decreased alveolar surface area (P < 0.001). Regression analyses demonstrated unique correlations between PRMfSAD and TBs, with decreased circularity (P < 0.001), decreased luminal area (P < 0.001), and complete obstruction (P = 0.008). PRMEmph correlated with increased airspace size (P < 0.001), decreased alveolar surface area (P = 0.003), and fewer alveolar attachments per TB (P = 0.01).Conclusions: PRMfSAD identifies areas of lung tissue with TB loss, luminal narrowing, and obstruction. This is the first confirmation that an imaging biomarker can identify terminal bronchial pathology in established COPD and provides a noninvasive imaging methodology to identify small airway damage in COPD.


Asunto(s)
Obstrucción de las Vías Aéreas/diagnóstico por imagen , Biomarcadores , Enfermedad Pulmonar Obstructiva Crónica/fisiopatología , Microtomografía por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad
19.
Carcinogenesis ; 40(2): 225-233, 2019 04 29.
Artículo en Inglés | MEDLINE | ID: mdl-30364933

RESUMEN

Identification of factors associated with human papillomavirus (HPV) cervical histopathology or recurrence/relapse following loop electrosurgical excision procedure (LEEP) would allow for better management of the disease. We investigated whether gene signatures could (i) associate with HPV cervical histopathology and (ii) identify women with post-LEEP disease recurrence/relapse. Gene array analysis was performed on paraffin-embedded cervical tissue-isolated RNA from two cross-sectional cohorts of antiretroviral therapy (ART)-suppressed HIV+HPV+ coinfected women: (i) 55 women in South Africa recruited into three groups: high risk (HR) (-) (n = 16) and HR (+) (n = 15) HPV without cervical histopathology and HR (+) HPV with cervical intraepithelial neoplasia (CIN) grade 1/2/3 (n = 24), (ii) 28 women in Botswana with CIN2/3 treated with LEEP 12-month prior to recruitment and presenting with (n = 13) and without (n = 15) lesion recurrence/relapse (tissue was analyzed at first LEEP). Three distinct gene expression signatures identified were able to segregate: (i) HR+ HPV and CIN1/2/3, (ii) HR HPV-free and cervical histopathology-free and (iii) HR+ HPV and cervical histopathology-free. Immune activation and neoplasia-associated genes (n = 272 genes; e.g. IL-1A, IL-8, TCAM1, POU4F1, MCM2, SMC1B, CXCL6, MMP12) were a feature of cancer precursor dysplasia within HR HPV infection. No difference in LEEP tissue gene expression was detected between women with or without recurrence/relapse. In conclusion, distinctive gene signatures were associated with presence of cervical histopathology in tissues from ART-suppressed HIV+/HPV+ coinfected women. Lack of detection of LEEP tissue gene signature able to segregate subsequent post-LEEP disease recurrence/relapse indicates additional factors independent of local gene expression as determinants of recurrence/relapse.


Asunto(s)
Cuello del Útero/patología , Expresión Génica/genética , Infecciones por Papillomavirus/genética , Infecciones por Papillomavirus/patología , Neoplasias del Cuello Uterino/genética , Neoplasias del Cuello Uterino/patología , Adulto , Antirretrovirales/farmacología , Cuello del Útero/efectos de los fármacos , Cuello del Útero/virología , Estudios Transversales , Femenino , Expresión Génica/efectos de los fármacos , Perfilación de la Expresión Génica/métodos , Infecciones por VIH/tratamiento farmacológico , Infecciones por VIH/patología , Infecciones por VIH/virología , Humanos , Recurrencia Local de Neoplasia/etiología , Recurrencia Local de Neoplasia/genética , Recurrencia Local de Neoplasia/patología , Recurrencia Local de Neoplasia/virología , Papillomaviridae/efectos de los fármacos , Infecciones por Papillomavirus/tratamiento farmacológico , Infecciones por Papillomavirus/virología , Neoplasias del Cuello Uterino/tratamiento farmacológico , Neoplasias del Cuello Uterino/virología , Displasia del Cuello del Útero/tratamiento farmacológico , Displasia del Cuello del Útero/genética , Displasia del Cuello del Útero/patología , Displasia del Cuello del Útero/virología
20.
Mem Cognit ; 47(5): 877-892, 2019 07.
Artículo en Inglés | MEDLINE | ID: mdl-30725375

RESUMEN

The reminding effect (Tullis, Benjamin, & Ross, Journal of Experimental Psychology: General, 143[4], 1526-1540, 2014) describes the increase in recall of a studied word when a related word is presented later in the study list. However, because the process of reminding is thought to occur during study, measures of test performance are indirect indicators of the process of reminding and are subject to influences that arise during testing. The present research seeks evidence of reminding during encoding. In two experiments, self-paced study times were used to index the online process of reminding. In Experiment 1, pairs of repeated words, related words, and unrelated words were included in a study list. Study times were shorter for words related to prior words in the list, but only when the lag between those two words was short. Relatedness affected study time by inspiring a reduction in the threshold for termination of study for related words under massed conditions. Experiment 2 replicated the reduction in study time for related words and further showed that the study time allotted to an associate of an earlier item predicted better memory for that earlier word on a cued-recall test. In this experiment, an advantage in memory was observed for related words, and self-paced study time of one word during encoding was predictive of later memory for a related word. These results suggest a link between the action of reminding at study, as indexed by changes in the distribution of study time, and later benefits to remembering, as revealed by the reminding effect.


Asunto(s)
Asociación , Señales (Psicología) , Recuerdo Mental/fisiología , Reconocimiento en Psicología/fisiología , Adulto , Humanos , Factores de Tiempo , Adulto Joven
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