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1.
Gels ; 10(3)2024 Feb 23.
Artículo en Inglés | MEDLINE | ID: mdl-38534582

RESUMEN

Hydrogels are a class of soft biomaterials and the material of choice for a myriad of biomedical applications due to their biocompatibility and highly tunable mechanical and biochemical properties. Specifically, light-mediated thiol-norbornene click reactions between norbornene-modified macromers and di-thiolated crosslinkers can be used to form base hydrogels amenable to spatial biochemical modifications via subsequent light reactions between pendant norbornenes in the hydrogel network and thiolated peptides. Macromers derived from natural sources (e.g., hyaluronic acid, gelatin, alginate) can cause off-target cell signaling, and this has motivated the use of synthetic macromers such as poly(ethylene glycol) (PEG). In this study, commercially available 8-arm norbornene-modified PEG (PEG-Nor) macromers were reacted with di-thiolated crosslinkers (dithiothreitol, DTT) to form synthetic hydrogels. By varying the PEG-Nor weight percent or DTT concentration, hydrogels with a stiffness range of 3.3 kPa-31.3 kPa were formed. Pendant norbornene groups in these hydrogels were used for secondary reactions to either increase hydrogel stiffness (by reacting with DTT) or to tether mono-thiolated peptides to the hydrogel network. Peptide functionalization has no effect on bulk hydrogel mechanics, and this confirms that mechanical and biochemical signals can be independently controlled. Using photomasks, thiolated peptides can also be photopatterned onto base hydrogels, and mesenchymal stem cells (MSCs) attach and spread on RGD-functionalized PEG-Nor hydrogels. MSCs encapsulated in PEG-Nor hydrogels are also highly viable, demonstrating the ability of this platform to form biocompatible hydrogels for 2D and 3D cell culture with user-defined mechanical and biochemical properties.

2.
J Rheumatol ; 2023 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-37399463

RESUMEN

OBJECTIVE: To evaluate the relevance and clinical utility of the Patient-Reported Outcomes Measurement Information System (PROMIS) surveys in patients with systemic lupus erythematosus (SLE). METHODS: Adults with SLE receiving routine outpatient care at a tertiary care academic medical center participated in a qualitative study. Patients completed PROMIS computerized adaptive tests (CATs) in 12 selected domains and rated the relevance of each domain to their experience with SLE. Focus groups and interviews were conducted to elucidate the relevance of the PROMIS surveys, identify additional domains of importance, and explore the utility of the surveys in clinical care. Focus group and interview transcripts were coded, and a thematic analysis was performed using an iterative inductive process. RESULTS: Twenty-eight women and 4 men participated in 4 focus groups and 4 interviews, respectively. Participants endorsed the relevance and comprehensiveness of the selected PROMIS domains in capturing the effect of SLE on their lives. They ranked fatigue, pain interference, sleep disturbance, physical function, and applied cognition abilities as the most salient health-related quality of life (HRQOL) domains. They suggested that the disease-agnostic PROMIS questions holistically captured their lived experience of SLE and its common comorbidities. Participants were enthusiastic about using PROMIS surveys in clinical care and described potential benefits in enabling disease monitoring and management, facilitating communication, and empowering patients. CONCLUSION: PROMIS includes the HRQOL domains that are of most importance to individuals with SLE. Patients suggest that these universal tools can holistically capture the impact of SLE and enhance routine clinical care.

3.
JAMA Neurol ; 79(11): 1113-1121, 2022 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-36121669

RESUMEN

Importance: Alzheimer disease (AD), a neurodegenerative disease characterized by ß-amyloid plaques and τ tangles in the brain, represents an unmet medical need with no fully approved therapeutics to modify disease progression. Objective: To investigate the safety and efficacy of crenezumab, a humanized monoclonal immunoglobulin G4 antibody targeting ß-amyloid oligomers, in participants with prodromal to mild (early) AD. Design, Setting, and Participants: Two phase 3 multicenter randomized double-blind placebo-controlled parallel-group efficacy and safety studies of crenezumab in participants with early AD, CREAD and CREAD2, were initiated in 2016 and 2017, respectively, and were designed to evaluate the efficacy and safety of crenezumab in participants with early AD. CREAD (194 sites in 30 countries) and CREAD2 (209 sites in 27 countries) were global multicenter studies. A total of 3736 and 3664 participants were screened in CREAD and CREAD2, respectively. A total of 3736 and 3664 participants were screened in CREAD and CREAD2, respectively. Both trials enrolled individuals aged 50 to 85 years with early AD. Participants with some comorbidities and evidence of cerebral infarction or more than 4 microbleeds or areas of leptomeningeal hemosiderosis on magnetic resonance imaging were excluded. After 2923 and 2858 were excluded, respectively, 813 participants in CREAD and 806 in CREAD2 were randomly assigned in a 1:1 ratio to either placebo or crenezumab. In the final analysis, there were 409 participants in the placebo group and 404 in the crenezumab group in CREAD and 399 in the placebo group and 407 in the crenezumab group in CREAD2. Data were analyzed up until January 2019 and August 2019, respectively. Interventions: Participants received placebo or 60 mg/kg crenezumab intravenously every 4 weeks for up to 100 weeks. Main Outcomes and Measures: The primary outcome was change from baseline to week 105 in Clinical Dementia Rating-Sum of Boxes (CDR-SB) score. Results: There were 813 participants in CREAD (mean [SD] age, 70.7 [8.2] years; 483 female and 330 male) and 806 in CREAD2 (mean [SD] age, 70.9 [7.7] years; 456 female and 350 male). Baseline characteristics were balanced between both groups. The between-group difference in mean change from baseline in CDR-SB score (placebo minus crenezumab) was -0.17 (95% CI, -0.86 to 0.53; P = .63) at week 105 in the CREAD study (88 placebo; 86 crenezumab). Compared with previous trials, no new safety signals were identified, and amyloid-related imaging abnormalities with edema were rare, mild, and transient. No meaningful changes in AD biomarkers were observed. Both studies were discontinued following a preplanned interim analysis indicating that CREAD was unlikely to meet the primary end point. Conclusions and Relevance: Crenezumab was well tolerated but did not reduce clinical decline in participants with early AD. Trial Registration: ClinicalTrials.gov Identifiers: CREAD, NCT02670083; CREAD2, NCT03114657.


Asunto(s)
Enfermedad de Alzheimer , Anticuerpos Monoclonales Humanizados , Adulto , Anciano , Femenino , Humanos , Masculino , Enfermedad de Alzheimer/diagnóstico por imagen , Enfermedad de Alzheimer/tratamiento farmacológico , Péptidos beta-Amiloides , Método Doble Ciego , Placa Amiloide , Resultado del Tratamiento , Anticuerpos Monoclonales Humanizados/efectos adversos , Anticuerpos Monoclonales Humanizados/uso terapéutico
4.
Front Genet ; 12: 665888, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34149808

RESUMEN

RNA sequencing (RNAseq) has been widely used to generate bulk gene expression measurements collected from pools of cells. Only relatively recently have single-cell RNAseq (scRNAseq) methods provided opportunities for gene expression analyses at the single-cell level, allowing researchers to study heterogeneous mixtures of cells at unprecedented resolution. Tumors tend to be composed of heterogeneous cellular mixtures and are frequently the subjects of such analyses. Extensive method developments have led to several protocols for scRNAseq but, owing to the small amounts of RNA in single cells, technical constraints have required compromises. For example, the majority of scRNAseq methods are limited to sequencing only the 3' or 5' termini of transcripts. Other protocols that facilitate full-length transcript profiling tend to capture only polyadenylated mRNAs and are generally limited to processing only 96 cells at a time. Here, we address these limitations and present a novel protocol that allows for the high-throughput sequencing of full-length, total RNA at single-cell resolution. We demonstrate that our method produced strand-specific sequencing data for both polyadenylated and non-polyadenylated transcripts, enabled the profiling of transcript regions beyond only transcript termini, and yielded data rich enough to allow identification of cell types from heterogeneous biological samples.

5.
J Alzheimers Dis ; 76(3): 967-979, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32568196

RESUMEN

BACKGROUND: Crenezumab is a fully humanized, monoclonal anti-amyloid-ß immunoglobulin G4 antibody. OBJECTIVE: This Phase Ib study (NCT02353598) evaluated the safety, tolerability, and pharmacokinetics of crenezumabat doses of ≤120 mg/kg administered intravenously every 4 weeks (q4w). Immunogenicity and exploratory biomarkers were also evaluated. METHODS: In this multicenter, double-blind study, participants (aged 50-90 years) with mild-to-moderate Alzheimer's disease (AD) and amyloid-positive positron emission tomography (PET) scan were randomized to receive crenezumab 30 or 45 mg/kg (Cohort 1, n = 21), 60 mg/kg (Cohort 2, n = 21), or 120 mg/kg (Cohort 3, n = 19) or corresponding placebo (n = 14) intravenously q4w for 13 weeks. Seventy-one participants were subsequently enrolled in an optional open-label extension (OLE) and received crenezumab at the originally assigned dose level, except for Cohort 3 (crenezumab 60 mg/kg during OLE). Participants received regular brain MRIs to assess amyloid-related imaging abnormalities (ARIA). Results up to Week 133 are reported. RESULTS: Approximately 94% of participants experienced ≥1 adverse event (AE). Most AEs were mild or moderate; 15.5% experienced a Grade ≥3 AE. No ARIA-edema/effusion (ARIA-E) events were observed. New ARIA-micro hemorrhages and hemosiderosis (ARIA-H) were reported in 4.9% (double-blind treatment period) and 9.9% (combined double-blind treatment and OLE periods) of participants. Steady-state trough concentrations of crenezumab were dose-proportional and maintained for each dose level. CONCLUSION: Crenezumab doses of ≤120 mg/kg intravenously q4w were well tolerated. The observed safety profile for ≤133 weeks of treatment in a mild-to-moderate AD population was similar to that seen in previous trials.


Asunto(s)
Enfermedad de Alzheimer/tratamiento farmacológico , Anticuerpos Monoclonales Humanizados/uso terapéutico , Encéfalo/efectos de los fármacos , Resultado del Tratamiento , Anciano , Anciano de 80 o más Años , Péptidos beta-Amiloides/inmunología , Anticuerpos Monoclonales Humanizados/efectos adversos , Biomarcadores/análisis , Método Doble Ciego , Femenino , Humanos , Masculino , Persona de Mediana Edad , Neuroimagen/métodos
6.
PLoS One ; 15(5): e0233566, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32442236

RESUMEN

Suspected bacterial urinary tract infections (UTI) are a common cause of overuse and misuse of antimicrobials. A bedside diagnostic test that could accurately predict urine culture results would prevent antimicrobial overuse, but accurate biomarkers have not yet been identified in veterinary medicine. The objective of this study was to evaluate urine myeloperoxidase (uMPO) as a rapidly available, accurate marker to predict urine culture results. We hypothesized that uMPO would be higher in dogs with a positive urine culture than in dogs with a negative urine culture, and that uMPO could be used to aid in the accurate diagnosis of significant bacteriuria. Urine samples were collected from a veterinary university clinical pathology lab. uMPO concentration was measured using a commercially available canine myeloperoxidase (MPO) enzyme-linked immunosorbent assay (ELISA). Following validation, samples from 98 dogs that had a urinalysis and urine culture performed as part of their diagnostic investigation were included. Forty-seven dogs had a negative urine culture and fifty-one dogs had a positive urine culture. uMPO levels were significantly higher in samples that had a positive culture (median 2.13 ng/ml; IQR 0.98-7.07) versus samples that had a negative culture (median 1.07 ng/ml; IQR 0.52-1.84)(p < 0.005). Based on receiver-operator characteristic, a cutoff of 0.55 ng/ml was chosen to maximize sensitivity and specificity. Using a cutoff of 0.55 ng/ml, uMPO had a sensitivity of 70% and specificity of 69% to determine the presence of a positive culture. However, the degree of overlap between groups may preclude the use of this test as a surrogate for urine culture in a clinical setting.


Asunto(s)
Infecciones Bacterianas , Bacteriuria , Biomarcadores/orina , Enfermedades de los Perros , Peroxidasa/orina , Animales , Bacterias/aislamiento & purificación , Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/orina , Infecciones Bacterianas/veterinaria , Bacteriuria/diagnóstico , Bacteriuria/orina , Bacteriuria/veterinaria , Enfermedades de los Perros/diagnóstico , Enfermedades de los Perros/orina , Perros , Ensayo de Inmunoadsorción Enzimática/métodos , Femenino , Masculino
7.
Alzheimers Dement ; 16(7): 1023-1030, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32418361

RESUMEN

INTRODUCTION: The API AutosomalDominant AD (ADAD) Colombia Trial is a placebo-controlled clinical trial of crenezumab in 252 cognitively unimpaired 30 to 60-year-old Presenilin 1 (PSEN1) E280A kindred members, including mutation carriers randomized to active treatment or placebo and non-carriers who receive placebo. METHODS: Of the 252 enrolled, we present data on a total of 242 mutation carriers and non-carriers matched by age range, excluding data on 10 participants to protect participant confidentiality, genetic status, and trial integrity. RESULTS: We summarize demographic, clinical, cognitive, and behavioral data from 167 mutation carriers and 75 non-carriers, 30 to 53 years of age. Carriers were significantly younger than non-carriers ((mean age ± SD) 37 ± 5 vs 42 ± 6), had significantly lower Mini Mental Status Exam (MMSE) scores (28.8 ± 1.4 vs 29.2 ± 1.0), and had consistently lower memory scores. DISCUSSION: Although PSEN1 E280A mutation carriers in the Trial are cognitively unimpaired, they have slightly lower MMSE and memory scores than non-carriers. Their demographic characteristics are representative of the local population.


Asunto(s)
Enfermedad de Alzheimer/genética , Enfermedad de Alzheimer/prevención & control , Anticuerpos Monoclonales Humanizados/uso terapéutico , Cognición/fisiología , Mutación , Presenilina-1/genética , Adulto , Enfermedad de Alzheimer/tratamiento farmacológico , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas
8.
JACC Case Rep ; 2(11): 1723-1729, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-34317044

RESUMEN

Tetralogy of Fallot (TOF) is a complex congenital cardiac defect. Surgical correction is well established as the treatment of choice and has resulted in a rapidly growing group of adults living with TOF. We describe potential complications of patients who have undergone TOF repair and were lost to follow-up. (Level of Difficulty: Intermediate.).

9.
Genetics ; 211(4): 1155-1177, 2019 04.
Artículo en Inglés | MEDLINE | ID: mdl-30765420

RESUMEN

To understand gene function, the cre/loxP conditional system is the most powerful available for temporal and spatial control of expression in mouse. However, the research community requires more cre recombinase expressing transgenic mouse strains (cre-drivers) that restrict expression to specific cell types. To address these problems, a high-throughput method for large-scale production that produces high-quality results is necessary. Further, endogenous promoters need to be chosen that drive cell type specific expression, or we need to further focus the expression by manipulating the promoter. Here we test the suitability of using knock-ins at the docking site 5' of Hprt for rapid development of numerous cre-driver strains focused on expression in adulthood, using an improved cre tamoxifen inducible allele (icre/ERT2), and testing a novel inducible-first, constitutive-ready allele (icre/f3/ERT2/f3). In addition, we test two types of promoters either to capture an endogenous expression pattern (MaxiPromoters), or to restrict expression further using minimal promoter element(s) designed for expression in restricted cell types (MiniPromoters). We provide new cre-driver mouse strains with applicability for brain and eye research. In addition, we demonstrate the feasibility and applicability of using the locus 5' of Hprt for the rapid generation of substantial numbers of cre-driver strains. We also provide a new inducible-first constitutive-ready allele to further speed cre-driver generation. Finally, all these strains are available to the research community through The Jackson Laboratory.


Asunto(s)
Encéfalo/metabolismo , Ojo/metabolismo , Técnicas de Sustitución del Gen/métodos , Ratones Transgénicos/genética , Tamoxifeno/farmacología , Activación Transcripcional/efectos de los fármacos , Animales , Efecto Fundador , Hipoxantina Fosforribosiltransferasa/genética , Hipoxantina Fosforribosiltransferasa/metabolismo , Integrasas/genética , Integrasas/metabolismo , Ratones , Ratones Endogámicos C57BL , Regiones Promotoras Genéticas
10.
Am J Physiol Endocrinol Metab ; 315(5): E795-E814, 2018 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-29509436

RESUMEN

Intrauterine growth restriction (IUGR) is linked to increased risk for chronic disease. Placental ischemia and insufficiency in the mother are implicated in predisposing IUGR offspring to metabolic dysfunction, including hypertension, insulin resistance, abnormalities in glucose homeostasis, and nonalcoholic fatty liver disease (NAFLD). It is unclear whether these metabolic disturbances contribute to the developmental origins of exaggerated cardiovascular-renal disease (CVRD) risk accompanying IUGR. IUGR impacts the pancreas, adipose tissue, and liver, which are hypothesized to program for hepatic insulin resistance and subsequent NAFLD. NAFLD is projected to become the major cause of chronic liver disease and contributor to uncontrolled type 2 diabetes mellitus, which is a leading cause of chronic kidney disease. While NAFLD is increased in experimental models of IUGR, lacking is a full comprehension of the mechanisms responsible for programming of NAFLD and whether this potentiates susceptibility to liver injury. The use of well-established and clinically relevant rodent models, which mimic the clinical characteristics of IUGR, metabolic disturbances, and increased blood pressure in the offspring, will permit investigation into mechanisms linking adverse influences during early life and later chronic health. The purpose of this review is to propose mechanisms, including those proinflammatory in nature, whereby IUGR exacerbates the pathogenesis of NAFLD and how these adverse programmed outcomes contribute to exaggerated CVRD risk. Understanding the etiology of the developmental origins of chronic disease will allow investigators to uncover treatment strategies to intervene in the mother and her offspring to halt the increasing prevalence of metabolic dysfunction and CVRD.


Asunto(s)
Enfermedades Cardiovasculares/etiología , Enfermedades Renales/etiología , Enfermedades Metabólicas/etiología , Enfermedad del Hígado Graso no Alcohólico/complicaciones , Animales , Femenino , Humanos , Insuficiencia Placentaria , Embarazo , Factores de Riesgo
12.
Cancer Immunol Res ; 4(10): 869-880, 2016 10.
Artículo en Inglés | MEDLINE | ID: mdl-27549124

RESUMEN

Genetically engineered T cells expressing CD19-specific chimeric antigen receptors (CAR) have shown impressive activity against B-cell malignancies, and preliminary results suggest that T cells expressing a first-generation disialoganglioside (GD2)-specific CAR can also provide clinical benefit in patients with neuroblastoma. We sought to assess the potential of GD2-CAR therapies to treat pediatric sarcomas. We observed that 18 of 18 (100%) of osteosarcomas, 2 of 15 (13%) of rhabdomyosarcomas, and 7 of 35 (20%) of Ewing sarcomas expressed GD2. T cells engineered to express a third-generation GD2-CAR incorporating the 14g2a-scFv with the CD28, OX40, and CD3ζ signaling domains (14g2a.CD28.OX40.ζ) mediated efficient and comparable lysis of both GD2+ sarcoma and neuroblastoma cell lines in vitro However, in xenograft models, GD2-CAR T cells had no antitumor effect against GD2+ sarcoma, despite effectively controlling GD2+ neuroblastoma. We observed that pediatric sarcoma xenografts, but not neuroblastoma xenografts, induced large populations of monocytic and granulocytic murine myeloid-derived suppressor cells (MDSC) that inhibited human CAR T-cell responses in vitro Treatment of sarcoma-bearing mice with all-trans retinoic acid (ATRA) largely eradicated monocytic MDSCs and diminished the suppressive capacity of granulocytic MDSCs. Combined therapy using GD2-CAR T cells plus ATRA significantly improved antitumor efficacy against sarcoma xenografts. We conclude that retinoids provide a clinically accessible class of agents capable of diminishing the suppressive effects of MDSCs, and that co-administration of retinoids may enhance the efficacy of CAR therapies targeting solid tumors. Cancer Immunol Res; 4(10); 869-80. ©2016 AACR.


Asunto(s)
Inmunoterapia Adoptiva/métodos , Células Supresoras de Origen Mieloide/efectos de los fármacos , Receptores de Antígenos de Linfocitos T/metabolismo , Sarcoma/terapia , Tretinoina/farmacología , Animales , Línea Celular Tumoral , Niño , Terapia Combinada , Gangliósidos/metabolismo , Humanos , Ratones Endogámicos NOD , Células Supresoras de Origen Mieloide/inmunología , Neuroblastoma/inmunología , Neuroblastoma/metabolismo , Neuroblastoma/patología , Sarcoma/inmunología , Sarcoma/metabolismo , Sarcoma/patología , Linfocitos T/inmunología , Linfocitos T/trasplante , Resultado del Tratamiento , Tretinoina/uso terapéutico , Células Tumorales Cultivadas , Ensayos Antitumor por Modelo de Xenoinjerto
13.
Can Rev Sociol ; 53(3): 316-36, 2016 08.
Artículo en Inglés | MEDLINE | ID: mdl-27527995

RESUMEN

The Arctic is one of the most radically altered parts of the world due to climate change, with significant social and cultural impacts as a result. Using discourse network analysis and qualitative textual analysis of articles published in the Globe and Mail and National Post during the period 2006 to 2010, we identify and analyze key frames that interpret the implications of climate change on the Arctic. We examine Canadian national news media coverage to ask: How does the Arctic enter media coverage of climate change? Is there evidence of a climate justice discourse in relation to regional disparities in the risks and harms of climate change between northern and southern Canada? Climate change in the Arctic is often framed through the lens of Canadian national interests, which downplays climate-related social impacts that are already occurring at subnational political and geographical scales. L'Arctique est une des régions du monde la plus radicalement altérée par le changement climatique, menant comme résultat des importants changements sociaux et culturels. En utilisant l'analyse des réseaux de discours ainsi que l'analyse textuelle qualitative des articles publiés dans le Globe and Mail et le National Post de 2006 à 2010, nous identifions and analysons des cadres clés qui servent à interpréter les conséquences du changement climatique dans l'Arctique. Nous examinons la couverture des médias nationaux canadiens pour pouvoir demander : comment est-ce que l'Arctique s'insère dans la couverture médiatique du changement climatique? Est-ce qu'il y a de la preuve d'un discours de la justice climatique en relation des disparités régionales des risques et méfaits du changement climatique entre le Canada du nord et du sud? Le changement climatique dans l'Arctique est souvent encadré à travers le prisme des intérêts nationaux canadiens, ce qui minimise les impacts sociaux reliés au climat qui se produisent actuellement aux échelons sous-nationaux politiques et géographiques.

14.
Nat Med ; 21(6): 581-90, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25939063

RESUMEN

Chimeric antigen receptors (CARs) targeting CD19 have mediated dramatic antitumor responses in hematologic malignancies, but tumor regression has rarely occurred using CARs targeting other antigens. It remains unknown whether the impressive effects of CD19 CARs relate to greater susceptibility of hematologic malignancies to CAR therapies, or superior functionality of the CD19 CAR itself. We show that tonic CAR CD3-ζ phosphorylation, triggered by antigen-independent clustering of CAR single-chain variable fragments, can induce early exhaustion of CAR T cells that limits antitumor efficacy. Such activation is present to varying degrees in all CARs studied, except the highly effective CD19 CAR. We further determine that CD28 costimulation augments, whereas 4-1BB costimulation reduces, exhaustion induced by persistent CAR signaling. Our results provide biological explanations for the antitumor effects of CD19 CARs and for the observations that CD19 CAR T cells incorporating the 4-1BB costimulatory domain are more persistent than those incorporating CD28 in clinical trials.


Asunto(s)
Neoplasias Hematológicas/inmunología , Receptores de Antígenos/inmunología , Linfocitos T/inmunología , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/inmunología , Antígenos CD19/inmunología , Antígenos CD19/metabolismo , Antígenos CD28/inmunología , Antígenos CD28/metabolismo , Línea Celular Tumoral , Neoplasias Hematológicas/patología , Neoplasias Hematológicas/terapia , Humanos , Inmunoterapia Adoptiva , Interleucina-2/inmunología , Activación de Linfocitos/inmunología , Receptores de Antígenos/metabolismo , Linfocitos T/patología , Miembro 9 de la Superfamilia de Receptores de Factores de Necrosis Tumoral/biosíntesis
15.
Life (Basel) ; 4(4): 887-902, 2014 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-25513758

RESUMEN

As the molecular top-down causality emerging through comparative genomics is combined with the bottom-up dynamic chemical networks of biochemistry, the molecular symbiotic relationships driving growth of the tree of life becomes strikingly apparent. These symbioses can be mutualistic or parasitic across many levels, but most foundational is the complex and intricate mutualism of nucleic acids and proteins known as the central dogma of biological information flow. This unification of digital and analog molecular information within a common chemical network enables processing of the vast amounts of information necessary for cellular life. Here we consider the molecular information pathways of these dynamic biopolymer networks from the perspective of their evolution and use that perspective to inform and constrain pathways for the construction of mutualistic polymers.

16.
J Am Chem Soc ; 136(43): 15146-9, 2014 Oct 29.
Artículo en Inglés | MEDLINE | ID: mdl-25313920

RESUMEN

In contrast to an expected Ostwald-like ripening of amyloid assemblies, the nucleating core of the Dutch mutant of the Aß peptide of Alzheimer's disease assembles through a series of conformational transitions. Structural characterization of the intermediate assemblies by isotope-edited IR and solid-state NMR reveals unexpected strand orientation intermediates and suggests new nucleation mechanisms in a progressive assembly pathway.


Asunto(s)
Péptidos beta-Amiloides/química , Agregado de Proteínas , Secuencia de Aminoácidos , Cinética , Modelos Moleculares , Estructura Secundaria de Proteína
17.
Sci Transl Med ; 6(237): 237ra67, 2014 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-24848257

RESUMEN

Suppression of the host's immune system plays a major role in cancer progression. Tumor signaling of programmed death 1 (PD1) on T cells and expansion of myeloid-derived suppressor cells (MDSCs) are major mechanisms of tumor immune escape. We sought to target these pathways in rhabdomyosarcoma (RMS), the most common soft tissue sarcoma of childhood. Murine RMS showed high surface expression of PD-L1, and anti-PD1 prevented tumor growth if initiated early after tumor inoculation; however, delayed anti-PD1 had limited benefit. RMS induced robust expansion of CXCR2(+)CD11b(+)Ly6G(hi) MDSCs, and CXCR2 deficiency prevented CD11b(+)Ly6G(hi) MDSC trafficking to the tumor. When tumor trafficking of MDSCs was inhibited by CXCR2 deficiency, or after anti-CXCR2 monoclonal antibody therapy, delayed anti-PD1 treatment induced significant antitumor effects. Thus, CXCR2(+)CD11b(+)Ly6G(hi) MDSCs mediate local immunosuppression, which limits the efficacy of checkpoint blockade in murine RMS. Human pediatric sarcomas also produce CXCR2 ligands, including CXCL8. Patients with metastatic pediatric sarcomas display elevated serum CXCR2 ligands, and elevated CXCL8 is associated with diminished survival in this population. We conclude that accumulation of MDSCs in the tumor bed limits the efficacy of checkpoint blockade in cancer. We also identify CXCR2 as a novel target for modulating tumor immune escape and present evidence that CXCR2(+)CD11b(+)Ly6G(hi) MDSCs are an important suppressive myeloid subset in pediatric sarcomas. These findings present a translatable strategy to improve the efficacy of checkpoint blockade by preventing trafficking of MDSCs to the tumor site.


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/farmacología , Antígeno B7-H1/antagonistas & inhibidores , Quimiotaxis/efectos de los fármacos , Células Madre Neoplásicas/efectos de los fármacos , Receptores de Interleucina-8B/antagonistas & inhibidores , Rabdomiosarcoma/tratamiento farmacológico , Escape del Tumor/efectos de los fármacos , Adolescente , Adulto , Animales , Anticuerpos Monoclonales/administración & dosificación , Antígenos Ly/metabolismo , Antígeno B7-H1/metabolismo , Antígeno CD11b/metabolismo , Estudios de Casos y Controles , Línea Celular Tumoral , Quimiocina CXCL1/sangre , Niño , Preescolar , Citocinas/metabolismo , Femenino , Humanos , Interleucina-8/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células Madre Neoplásicas/inmunología , Células Madre Neoplásicas/metabolismo , Células Madre Neoplásicas/patología , Pronóstico , Receptores de Interleucina-8B/deficiencia , Receptores de Interleucina-8B/genética , Rabdomiosarcoma/sangre , Rabdomiosarcoma/inmunología , Rabdomiosarcoma/metabolismo , Rabdomiosarcoma/patología , Factores de Tiempo , Carga Tumoral/efectos de los fármacos , Microambiente Tumoral , Adulto Joven
18.
Nucleic Acids Res ; 42(8): 5007-19, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24598261

RESUMEN

Irradiation of G-quadruplex forming human telomeric DNA with ultraviolet B (UVB) light results in the formation of anti cyclobutane pyrimidine dimers (CPDs) between loop 1 and loop 3 in the presence of potassium ions but not sodium ions. This was unexpected because the sequences involved favor the nonphotoreactive hybrid conformations in K(+) solution, whereas a potentially photoreactive basket conformation is favored in Na(+) solution. To account for these contradictory results, it was proposed that the loops are too far apart in the basket conformation in Na(+) solution but close enough in a two G-tetrad basket-like form 3 conformation that can form in K(+) solution. In the current study, Na(+) was still found to inhibit anti CPD formation in sequences designed to stabilize the form 3 conformation. Furthermore, anti CPD formation in K(+) solution was slower for the sequence previously shown to exist primarily in the proposed photoreactive form 3 conformation than the sequence shown to exist primarily in a nonphotoreactive hybrid conformation. These results suggest that the form 3 conformation is not the principal photoreactive conformation, and that G-quadruplexes in K(+) solution are dynamic and able to access photoreactive conformations more easily than in Na(+) solution.


Asunto(s)
ADN/química , G-Cuádruplex , Potasio/química , Dímeros de Pirimidina/química , Telómero/química , Secuencia de Bases , Cromatografía Líquida de Alta Presión/métodos , ADN/efectos de la radiación , G-Cuádruplex/efectos de la radiación , Humanos , Mutación , Sodio/química , Estereoisomerismo , Rayos Ultravioleta
19.
J Surg Res ; 187(2): 466-70, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24326179

RESUMEN

BACKGROUND: A novel data warehouse based on automated retrieval from an institutional health care information system (HIS) was made available to be compared with a traditional prospectively maintained surgical database. METHODS: A newly established institutional data warehouse at a single-institution academic medical center autopopulated by HIS was queried for International Classification of Diseases, 9th Revision, Clinical Modification (ICD-9-CM) diagnosis codes for pancreatic neoplasm. Patients with ICD-9-CM diagnosis codes for pancreatic neoplasm were captured. A parallel query was performed using a prospective database populated by manual entry. Duplicated patients and those unique to either data set were identified. All patients were manually reviewed to determine the accuracy of diagnosis. RESULTS: A total of 1107 patients were identified from the HIS-linked data set with pancreatic neoplasm from 1999-2009. Of these, 254 (22.9%) patients were also captured by the surgical database, whereas 853 (77.1%) patients were only in the HIS-linked data set. Manual review of the HIS-only group demonstrated that 45.0% of patients were without identifiable pancreatic pathology, suggesting erroneous capture, whereas 36.3% of patients were consistent with pancreatic neoplasm and 18.7% with other pancreatic pathology. Of the 394 patients identified by the surgical database, 254 (64.5%) patients were captured by HIS, whereas 140 (35.5%) patients were not. Manual review of patients only captured by the surgical database demonstrated 85.9% with pancreatic neoplasm and 14.1% with other pancreatic pathology. Finally, review of the 254 patient overlap demonstrated that 80.3% of patients had pancreatic neoplasm and 19.7% had other pancreatic pathology. CONCLUSIONS: These results suggest that cautious interpretation of administrative data rely only on ICD-9-CM diagnosis codes and clinical correlation through previously validated mechanisms.


Asunto(s)
Investigación Biomédica/métodos , Bases de Datos Factuales/normas , Registros Electrónicos de Salud/normas , Sistemas de Información en Hospital/normas , Neoplasias Pancreáticas/diagnóstico , Neoplasias Pancreáticas/cirugía , Centros Médicos Académicos , Anciano , Femenino , Humanos , Clasificación Internacional de Enfermedades , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados
20.
HPB (Oxford) ; 16(6): 528-33, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24245953

RESUMEN

BACKGROUND: Patients are increasingly confronted with systems for rating hospitals. However, the correlations between publicized ratings and actual outcomes after pancreatectomy are unknown. METHODS: The Massachusetts Division of Health Care Finance and Policy Hospital Inpatient Discharge Database was queried to identify pancreatic cancer resections carried out during 2005-2009. Hospitals performing fewer than 10 pancreatic resections in the 5-year period were excluded. Primary outcomes included mortality, complications, median length of stay (LoS) and a composite outcomes score (COS) combining primary outcomes. Ranks were determined and compared for: (i) volume, and (ii) ratings identified from consumer-directed hospital ratings including the US News & World Report (USN), Consumer Reports, Healthgrades and Hospital Compare. An inter-rater reliability analysis was performed and correlation coefficients (r) between outcomes and ratings, and between rating systems were calculated. RESULTS: Eleven hospitals in which a total of 804 pancreatectomies were conducted were identified. Surgical volume correlated with overall outcome, but was not the strongest indicator. The highest correlation referred to that between USN rank and overall outcome. Mortality was most strongly correlated with Healthgrades ratings (r = 0.50); however, Healthgrades ratings demonstrated poorer correlations with all other outcomes. Consumer Reports ratings showed inverse correlations. CONCLUSIONS: The plethora of publicly available hospital ratings systems demonstrates heterogeneity. Volume remains a good but imperfect indicator of surgical outcomes. Further systematic investigation into which measures predict quality outcomes in pancreatic cancer surgery will benefit both patients and providers.


Asunto(s)
Hospitales de Alto Volumen/normas , Evaluación de Procesos y Resultados en Atención de Salud/normas , Pancreatectomía/normas , Neoplasias Pancreáticas/cirugía , Indicadores de Calidad de la Atención de Salud/normas , Técnicas de Apoyo para la Decisión , Humanos , Tiempo de Internación , Massachusetts , Pancreatectomía/efectos adversos , Pancreatectomía/mortalidad , Neoplasias Pancreáticas/mortalidad , Complicaciones Posoperatorias/mortalidad , Complicaciones Posoperatorias/terapia , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo , Resultado del Tratamiento
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