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1.
Cell ; 179(7): 1636-1646.e15, 2019 12 12.
Artículo en Inglés | MEDLINE | ID: mdl-31787378

RESUMEN

B cell receptor (BCR) sequencing is a powerful tool for interrogating immune responses to infection and vaccination, but it provides limited information about the antigen specificity of the sequenced BCRs. Here, we present LIBRA-seq (linking B cell receptor to antigen specificity through sequencing), a technology for high-throughput mapping of paired heavy- and light-chain BCR sequences to their cognate antigen specificities. B cells are mixed with a panel of DNA-barcoded antigens so that both the antigen barcode(s) and BCR sequence are recovered via single-cell next-generation sequencing. Using LIBRA-seq, we mapped the antigen specificity of thousands of B cells from two HIV-infected subjects. The predicted specificities were confirmed for a number of HIV- and influenza-specific antibodies, including known and novel broadly neutralizing antibodies. LIBRA-seq will be an integral tool for antibody discovery and vaccine development efforts against a wide range of antigen targets.


Asunto(s)
Mapeo Epitopo/métodos , Epítopos/química , Receptores de Antígenos de Linfocitos B/química , Análisis de Secuencia de ADN/métodos , Análisis de la Célula Individual/métodos , Anticuerpos Neutralizantes/química , Anticuerpos Neutralizantes/inmunología , Antígenos/química , Antígenos/inmunología , Células Cultivadas , Epítopos/inmunología , Células HEK293 , Anticuerpos Anti-VIH/química , Anticuerpos Anti-VIH/inmunología , Secuenciación de Nucleótidos de Alto Rendimiento/métodos , Ensayos Analíticos de Alto Rendimiento/métodos , Humanos , Receptores de Antígenos de Linfocitos B/inmunología , Células THP-1
2.
Nature ; 611(7935): 352-357, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36289331

RESUMEN

The vertebrate adaptive immune system modifies the genome of individual B cells to encode antibodies that bind particular antigens1. In most mammals, antibodies are composed of heavy and light chains that are generated sequentially by recombination of V, D (for heavy chains), J and C gene segments. Each chain contains three complementarity-determining regions (CDR1-CDR3), which contribute to antigen specificity. Certain heavy and light chains are preferred for particular antigens2-22. Here we consider pairs of B cells that share the same heavy chain V gene and CDRH3 amino acid sequence and were isolated from different donors, also known as public clonotypes23,24. We show that for naive antibodies (those not yet adapted to antigens), the probability that they use the same light chain V gene is around 10%, whereas for memory (functional) antibodies, it is around 80%, even if only one cell per clonotype is used. This property of functional antibodies is a phenomenon that we call light chain coherence. We also observe this phenomenon when similar heavy chains recur within a donor. Thus, although naive antibodies seem to recur by chance, the recurrence of functional antibodies reveals surprising constraint and determinism in the processes of V(D)J recombination and immune selection. For most functional antibodies, the heavy chain determines the light chain.


Asunto(s)
Anticuerpos , Selección Clonal Mediada por Antígenos , Cadenas Pesadas de Inmunoglobulina , Cadenas Ligeras de Inmunoglobulina , Animales , Secuencia de Aminoácidos , Anticuerpos/química , Anticuerpos/genética , Anticuerpos/inmunología , Antígenos/química , Antígenos/inmunología , Linfocitos B/citología , Linfocitos B/inmunología , Linfocitos B/metabolismo , Regiones Determinantes de Complementariedad/química , Regiones Determinantes de Complementariedad/inmunología , Cadenas Pesadas de Inmunoglobulina/química , Cadenas Pesadas de Inmunoglobulina/genética , Cadenas Pesadas de Inmunoglobulina/inmunología , Mamíferos , Cadenas Ligeras de Inmunoglobulina/química , Cadenas Ligeras de Inmunoglobulina/genética , Cadenas Ligeras de Inmunoglobulina/inmunología , Memoria Inmunológica , Recombinación V(D)J , Selección Clonal Mediada por Antígenos/genética , Selección Clonal Mediada por Antígenos/inmunología
3.
Blood ; 139(21): 3194-3203, 2022 05 26.
Artículo en Inglés | MEDLINE | ID: mdl-35358299

RESUMEN

Platelets are critical in hemostasis and a major contributor to arterial thrombosis (AT). (Pre)clinical studies suggest platelets also contribute to venous thrombosis (VT), but the mechanisms are largely unknown. We hypothesized that in VT, platelets use signaling machinery distinct from AT. Here we aimed to characterize the contributions of platelet G protein-coupled (GPCR) and immunoreceptor tyrosine-based activation motif (ITAM) receptor signaling to VT. Wild-type (WT) and transgenic mice were treated with inhibitors to selectively inhibit platelet-signaling pathways: ITAM-CLEC2 (Clec2mKO), glycoprotein VI (JAQ1 antibody), and Bruton's tyrosine kinase (ibrutinib); GPCR-cyclooxygenase 1 (aspirin); and P2Y12 (clopidogrel). VT was induced by inferior vena cava stenosis. Thrombin generation in platelet-rich plasma and whole-blood clot formation were studied ex vivo. Intravital microscopy was used to study platelet-leukocyte interactions after flow restriction. Thrombus weights were reduced in WT mice treated with high-dose aspirin + clopidogrel (dual antiplatelet therapy [DAPT]) but not in mice treated with either inhibitor alone or low-dose DAPT. Similarly, thrombus weights were reduced in mice with impaired ITAM signaling (Clec2mKO + JAQ1; WT + ibrutinib) but not in Clec2mKO or WT + JAQ1 mice. Both aspirin and clopidogrel, but not ibrutinib, protected mice from FeCl3-induced AT. Thrombin generation and clot formation were normal in blood from high-dose DAPT- or ibrutinib-treated mice; however, platelet adhesion and platelet-neutrophil aggregate formation at the vein wall were reduced in mice treated with high-dose DAPT or ibrutinib. In summary, VT initiation requires platelet activation via GPCRs and ITAM receptors. Strong inhibition of either signaling pathway reduces VT in mice.


Asunto(s)
Trombosis , Trombosis de la Vena , Animales , Aspirina , Plaquetas/metabolismo , Clopidogrel/metabolismo , Clopidogrel/farmacología , Proteínas de Unión al GTP , Motivo de Activación del Inmunorreceptor Basado en Tirosina , Ratones , Ratones Transgénicos , Activación Plaquetaria , Agregación Plaquetaria , Inhibidores de Agregación Plaquetaria/farmacología , Trombina/metabolismo , Trombosis/metabolismo , Trombosis de la Vena/metabolismo
4.
Nano Lett ; 23(3): 931-938, 2023 Feb 08.
Artículo en Inglés | MEDLINE | ID: mdl-36700844

RESUMEN

The need for novel materials for energy storage and generation calls for chemical control at the atomic scale in nanomaterials. Ordered double-transition-metal MXenes expanded the chemical diversity of the family of atomically layered 2D materials since their discovery in 2015. However, atomistic tunability of ordered MXenes to achieve ideal composition-property relationships has not been yet possible. In this study, we demonstrate the synthesis of Mo2+αNb2-αAlC3 MAX phases (0 ≤ α ≤ 0.3) and confirm the preferential ordering behavior of Mo and Nb in the outer and inner M layers, respectively, using density functional theory, Rietveld refinement, and electron microscopy methods. We also synthesize their 2D derivative Mo2+αNb2-αC3Tx MXenes and exemplify the effect of preferential ordering on their hydrogen evolution reaction electrocatalytic behavior. This study seeks to inspire further exploration of the ordered double-transition-metal MXene family and contribute composition-behavior tools toward application-driven design of 2D materials.

5.
Biol Reprod ; 109(2): 125-136, 2023 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-37265359

RESUMEN

The fallopian tubes (FTs) are part of the female upper genital tract. The healthy FT provides the biological environment for successful fertilization and facilitates the subsequent movement of the conceptus to the endometrial cavity. However, when the FT is damaged, as with salpingitis, pyosalpinx, and hydrosalpinx, it may increase the risk of an ectopic pregnancy, a life-threatening condition. Decidualization refers to a multifactorial process by which the endometrium changes to permit blastocyst implantation. The decidualization reaction is vital for endometrial receptivity during the window of implantation. To date, no comprehensive review that collates evidence on decidualization in the human FT has been conducted. Therefore, the aim of this review is to compile the current evidence on cellular decidualization occurring in the healthy and pathological FT in women of reproductive age. A literature search was conducted using five databases and identified 746 articles, 24 of which were analyzed based on inclusion and exclusion criteria. The available evidence indicates that the FT are able to undergo decidual changes under specific circumstances; however, the exact mechanism by which this occurs is poorly understood. Further research is needed to elucidate the mechanism by which decidualization can occur in the FT.


Asunto(s)
Endometrio , Trompas Uterinas , Embarazo , Femenino , Humanos , Implantación del Embrión , Útero , Decidua , Células del Estroma
6.
Artif Organs ; 47(2): 361-369, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36271639

RESUMEN

BACKGROUND: Impella 5.5 (Abiomed; Danvers, MA) (IMP5) is a commonly used, surgically implanted, tMCS device that requires systemic anticoagulation and purge solution to avoid pump failure. To avoid heparin-induced thrombocytopenia (HIT) from unfractionated heparin (UFH) use, our program has explored the utility of bivalirudin (BIV) for systemic anticoagulation and sodium bicarbonate-dextrose purge solution (SBPS) in IMP5.5. METHODS: This single center, retrospective study included 34 patients supported on IMP5.5 with BIV based AC and SBPS between December 1st 2020 to December 1st 2021.The efficacy and safety end points were incidence of development of HIT, Tissue Plasminogen Activator (tPA) use for suspected pump thrombosis, stroke, and device failure as well as clinically significant bleeding. RESULTS: The median duration of IMP5.5 support was 9.8 days (IQR: 6-15). Most patients were bridged to HTX (58%) followed by recovery (27%) and LVAD implantation (15%). Patients were therapeutic on bivalirudin for 64% of their IMP5.5 support. One patient (2.9%) suffered from ischemic stroke and 26.5% (9) patients developed clinically significant bleeding. tPA was administered to 7(21%) patients. One patient in the entire cohort developed HIT. CONCLUSIONS: Our experience supports the use of systemic BIV and SBPS as a method to avoid heparin exposure in a patient population predisposed to the development of HIT.


Asunto(s)
Heparina , Trombocitopenia , Humanos , Heparina/efectos adversos , Anticoagulantes/efectos adversos , Activador de Tejido Plasminógeno/efectos adversos , Bicarbonato de Sodio , Estudios Retrospectivos , Hirudinas/efectos adversos , Fragmentos de Péptidos/efectos adversos , Hemorragia/inducido químicamente , Proteínas Recombinantes/efectos adversos , Resultado del Tratamiento
7.
Am J Dermatopathol ; 45(3): 192-195, 2023 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-36728283

RESUMEN

ABSTRACT: Adenodermatofibromas are an extremely rare subtype of dermatofibroma (DF) characterized by a dermal proliferation of spindle-shaped fibroblasts and histocytes, dilated glandular structures with apocrine secretion, and prominent vascular proliferation, with or without hemosiderotic features. We describe a recent extraordinary case of a hemosiderotic adenodermatofibroma in a 25-year-old female. We review histologic findings and theories behind etiology, as well as review the spectrum of clinical presentations for this lesion. We also discuss imaging findings that may make identification of these entities challenging.


Asunto(s)
Hemosiderosis , Histiocitoma Fibroso Benigno , Neoplasias Cutáneas , Femenino , Humanos , Adulto , Neoplasias Cutáneas/patología , Histiocitoma Fibroso Benigno/patología , Hemosiderosis/patología , Fibroblastos/patología , Histiocitos/patología
8.
J Virol ; 95(8)2021 03 25.
Artículo en Inglés | MEDLINE | ID: mdl-33536169

RESUMEN

Cellular immune responses to Gag correlate with improved HIV viral control. The full extent of cellular immune responses comprise both the number of epitopes recognized by CD4+ and CD8+ T cells, as well as the diversity of the T cell receptor (TCR) repertoire directed against each epitope. The optimal diversity of the responsive TCR repertoire is unclear. Therefore, we evaluated the TCR diversity of CD4+ and CD8+ T cells responding to HIV-1 Gag to determine if TCR diversity correlates with clinical or virologic metrics. Previous studies of TCR repertoires have been limited primarily to CD8+ T cell responses directed against a small number of well-characterized T cell epitopes restricted by specific human leucocyte antigens. We stimulated peripheral blood mononuclear cells from 21chronic HIV-infected individuals overnight with a pool of HIV-1 Gag peptides, followed by sorting of activated CD4+ and CD8+ T cells and TCR deep sequencing. We found Gag-reactive CD8+ T cells to be more oligoclonal, with a few dominant TCRs comprising the bulk of the repertoire, compared to the highly diverse TCR repertoires of Gag-reactive CD4+ T cells. HIV viral sequencing of the same donors revealed that high CD4+ T cell TCR diversity was strongly associated with lower HIV Gag genetic diversity. We conclude that the TCR repertoire of Gag-reactive CD4+ T helper cells display substantial diversity without a clearly dominant circulating TCR clonotype, in contrast to a hierarchy of dominant TCR clonotypes in the Gag-reactive CD8+ T cells, and may serve to limit HIV diversity during chronic infection.IMPORTANCE Human T cells recognize portions of viral proteins bound to host molecules (human leucocyte antigens) on the surface of infected cells. T cells recognize these foreign proteins through their T cell receptors (TCRs), which are formed by the assortment of several available V, D and J genes to create millions of combinations of unique TCRs. We measured the diversity of T cells responding to the HIV Gag protein. We found the CD8+ T cell response is primarily made up of a few dominant unique TCRs whereas the CD4+ T cell subset has a much more diverse repertoire of TCRs. We also found there was less change in the virus sequences in subjects with more diverse TCR repertoires. HIV has a high mutation rate, which allows it to evade the immune response. Our findings describe the characteristics of a virus-specific T cell response that may allow it to limit viral evolution.

9.
Artif Organs ; 46(1): 117-127, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34425001

RESUMEN

We previously reported low rates of pump thrombosis and hemorrhagic stroke, but increased bleeding, under our original antithrombosis protocol (P1) in HeartWare recipients. We designed and implemented a revised protocol (P2) to reduce complexity and bleeding. Thrombelastography and PFA-100 guide antiplatelet titration. Goals for P2 were altered to decrease antiplatelet use and anticoagulation intensity. We compared the incidence and rates of gastrointestinal bleeding (GIB), embolic (eCVA) and hemorrhagic (hCVA) stroke, pump thrombosis (PT), and total bleeding (GIB+hCVA), total thrombosis (eCVA+PT), and total events between P1 and P2. Laboratory and medication data were assessed. Patients with and without hemocompatibility-related adverse events (HRAEs) were compared. The study included 123 patients (P1: 65; P2: 58). GIB rate decreased (P1: 0.66; P2 0.30 EPPY, P = .003). CVA rates and incidence were statistically similar, although hCVA incidence increased (P1: 3%; P2: 12%, P = .06). Incidence (P1: 3%; P2: 16%, P = .02) and rate (P1: 0.03; P2: 0.12 EPPY, P = .08) of PT increased. Incidence and rate of overall HRAEs and thrombotic events were similar, while bleeding rate decreased (P1: 0.69; P2: 0.40 EPPY, P = .02). Twelve-month medication burden decreased. Compared to non-HRAE patients, patients with bleeding HRAEs had more antiplatelet and pentoxifylline use, but less statin use; and lower PFAs. Patients with thrombotic HRAEs had less dual antiplatelet use, lower INRs, R-times, and PFA-ADP values. A revised antithrombotic protocol decreased GIB and overall hemorrhagic HRAE rate and medication burden. Unfortunately, PT increased. Non-HRAE and HRAE patients differed in anticoagulation and antiplatelet intensity. These differences will guide the revision of P2.


Asunto(s)
Fibrinolíticos/uso terapéutico , Corazón Auxiliar/efectos adversos , Trombosis/prevención & control , Femenino , Fibrinolíticos/administración & dosificación , Hemorragia Gastrointestinal/epidemiología , Hemorragia Gastrointestinal/etiología , Insuficiencia Cardíaca/terapia , Humanos , Masculino , Persona de Mediana Edad , Accidente Cerebrovascular/epidemiología , Accidente Cerebrovascular/etiología , Tromboelastografía
10.
Nat Prod Rep ; 38(3): 489-509, 2021 03 01.
Artículo en Inglés | MEDLINE | ID: mdl-32929442

RESUMEN

Covering: Up to July 2020Ribosomal antimicrobial peptide (AMP) natural products, also known as ribosomally synthesized and post-translationally modified peptides (RiPPs) or host defense peptides, demonstrate potent bioactivities and impressive complexity that complicate molecular and biological characterization. Tandem mass spectrometry (MS) has rapidly accelerated bioactive peptide sequencing efforts, yet standard workflows insufficiently address intrinsic AMP diversity. Herein, orthogonal approaches to accelerate comprehensive and accurate molecular characterization without the need for prior isolation are reviewed. Chemical derivatization, proteolysis (enzymatic and chemical cleavage), multistage MS fragmentation, and separation (liquid chromatography and ion mobility) strategies can provide complementary amino acid composition and post-translational modification data to constrain sequence solutions. Examination of two complex case studies, gomesin and styelin D, highlights the practical implementation of the proposed approaches. Finally, we emphasize the importance of heterogeneous AMP peptidoforms that confer varying biological function, an area that warrants significant further development.


Asunto(s)
Aminoácidos/análisis , Productos Biológicos/química , Espectrometría de Masas/métodos , Proteínas Citotóxicas Formadoras de Poros/química , Proteínas Citotóxicas Formadoras de Poros/metabolismo , Alquilación , Aminoácidos/química , Péptidos Catiónicos Antimicrobianos/química , Ciclización , Glicosilación , Procesamiento Proteico-Postraduccional , Estereoisomerismo
11.
Gastroenterology ; 159(6): 2077-2091.e8, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32891625

RESUMEN

BACKGROUND & AIMS: Severe injury to the lining of the stomach leads to changes in the epithelium (reprogramming) that protect and promote repair of the tissue, including development of spasmolytic polypeptide-expressing metaplasia (SPEM) and tuft and foveolar cell hyperplasia. Acute gastric damage elicits a type-2 inflammatory response that includes production of type-2 cytokines and infiltration by eosinophils and alternatively activated macrophages. Stomachs of mice that lack interleukin 33 (IL33) or interleukin 13 (IL13) did not undergo epithelial reprogramming after drug-induced injury. We investigated the role of group 2 innate lymphoid cells (ILC2s) in gastric epithelial repair. METHODS: Acute gastric injury was induced in C57BL/6J mice (wild-type and RAG1 knockout) by administration of L635. We isolated ILC2s by flow cytometry from stomachs of mice that were and were not given L635 and performed single-cell RNA sequencing. ILC2s were depleted from wild-type and RAG1-knockout mice by administration of anti-CD90.2. We assessed gastric cell lineages, markers of metaplasia, inflammation, and proliferation. Gastric tissue microarrays from patients with gastric adenocarcinoma were analyzed by immunostaining. RESULTS: There was a significant increase in the number of GATA3-positive ILC2s in stomach tissues from wild-type mice after L635-induced damage, but not in stomach tissues from IL33-knockout mice. We characterized a marker signature of gastric mucosal ILC2s and identified a transcription profile of metaplasia-associated ILC2s, which included changes in expression of Il5, Il13, Csf2, Pd1, and Ramp3; these changes were validated by quantitative polymerase chain reaction and immunocytochemistry. Depletion of ILC2s from mice blocked development of metaplasia after L635-induced injury in wild-type and RAG1-knockout mice and prevented foveolar and tuft cell hyperplasia and infiltration or activation of macrophages after injury. Numbers of ILC2s were increased in stomach tissues from patients with SPEM compared with patients with normal corpus mucosa. CONCLUSIONS: In analyses of stomach tissues from mice with gastric tissue damage and patients with SPEM, we found evidence of type 2 inflammation and increased numbers of ILC2s. Our results suggest that ILC2s coordinate the metaplastic response to severe gastric injury.


Asunto(s)
Mucosa Gástrica/patología , Inmunidad Innata , Subgrupos Linfocitarios/inmunología , Animales , Modelos Animales de Enfermedad , Mucosa Gástrica/efectos de los fármacos , Mucosa Gástrica/inmunología , Humanos , Interleucina-33/genética , Metaplasia/inducido químicamente , Metaplasia/genética , Metaplasia/inmunología , Ratones , Ratones Noqueados
12.
PLoS Pathog ; 15(12): e1008177, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31821379

RESUMEN

Human immunodeficiency virus (HIV) can adapt to an individual's T cell immune response via genomic mutations that affect antigen recognition and impact disease outcome. These viral adaptations are specific to the host's human leucocyte antigen (HLA) alleles, as these molecules determine which peptides are presented to T cells. As HLA molecules are highly polymorphic at the population level, horizontal transmission events are most commonly between HLA-mismatched donor/recipient pairs, representing new immune selection environments for the transmitted virus. In this study, we utilised a deep sequencing approach to determine the HIV quasispecies in 26 mother-to-child transmission pairs where the potential for founder viruses to be pre-adapted is high due to the pairs being haplo-identical at HLA loci. This scenario allowed the assessment of specific HIV adaptations following transmission in either a non-selective immune environment, due to recipient HLA mismatched to original selecting HLA, or a selective immune environment, mediated by matched donor/recipient HLA. We show that the pattern of reversion or fixation of HIV adaptations following transmission provides insight into the replicative cost, and likely compensatory networks, associated with specific adaptations in vivo. Furthermore, although transmitted viruses were commonly heavily pre-adapted to the child's HLA genotype, we found evidence of de novo post-transmission adaptation, representing new epitopes targeted by the child's T cell response. High-resolution analysis of HIV adaptation is relevant when considering vaccine and cure strategies for individuals exposed to adapted viruses via transmission or reactivated from reservoirs.


Asunto(s)
Adaptación Biológica/genética , Infecciones por VIH/genética , VIH-1/genética , Transmisión Vertical de Enfermedad Infecciosa , Adaptación Biológica/inmunología , Adulto , Niño , Preescolar , Evolución Molecular , Femenino , Infecciones por VIH/inmunología , Infecciones por VIH/transmisión , VIH-1/inmunología , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Lactante , Masculino , Persona de Mediana Edad
13.
Clin Radiol ; 76(5): 333-341, 2021 May.
Artículo en Inglés | MEDLINE | ID: mdl-33461746

RESUMEN

AIM: To establish the diagnostic accuracy of the Liver Imaging Reporting and Data System (LI-RADS) for hepatocellular carcinoma (HCC) and compare its performance to that of international criteria from European Assofor the Study of the Liver (EASL), Japan Society of Hepatology (JSH), Asian Pacific Association for the Study of the Liver (APASL), and Organ Procurement and Transplantation Network (OPTN), and to the reporting radiologist's overall opinion regarding the probability of a nodule being a HCC by correlating with a histological diagnosis from whole liver explants. MATERIALS AND METHODS: The present single-centre, retrospective review selected participants based on the following criteria: adults (≥18 years) listed for liver transplantation in 2014/2015, with liver cirrhosis at the time of magnetic resonance imaging (MRI) with hepatocyte specific contrast agent, and at least one liver lesion ≥10 mm on MRI with histology from subsequent liver explant for comparison. Each lesion was assessed against international criteria and given a "radiologist opinion" score of 1-5 (1 = definitely benign, 5 = definitely HCC). RESULTS: Total 268 patient records were reviewed, with 105 eligible lesions identified from 47 patients. Median lesion size was 15.5 mm (range 10-68 mm). Sensitivity (%), specificity (%), and positive predictive value (PPV; %) for LI-RADS LR5 was 45, 89, and 89, for LI-RADS LR4+5 + TIV was 61, 80, and 86, for EASL was 44, 86 and 86, for JSH/APASL was 64, 81, and 87, for OPTN was 36, 90, and 88, and for "radiologist impression" of probably or definitely HCC was 79, 79, and 88 respectively. CONCLUSIONS: MRI has moderate sensitivity and good specificity for the diagnosis of HCC with considerable variation depending on criteria used. OPTN criteria have the best specificity, but low sensitivity. "Radiologist opinion" gives highest overall accuracy with increases in sensitivity and reduction in specificity when compared to the imaging criteria.


Asunto(s)
Carcinoma Hepatocelular/diagnóstico por imagen , Gadolinio DTPA , Aumento de la Imagen/métodos , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Sistemas de Información Radiológica , Adulto , Anciano , Carcinoma Hepatocelular/complicaciones , Carcinoma Hepatocelular/patología , Medios de Contraste , Femenino , Humanos , Hígado/diagnóstico por imagen , Hígado/patología , Cirrosis Hepática/patología , Neoplasias Hepáticas/complicaciones , Neoplasias Hepáticas/patología , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Estudios Retrospectivos , Sensibilidad y Especificidad
14.
J Chem Phys ; 155(8): 084904, 2021 Aug 28.
Artículo en Inglés | MEDLINE | ID: mdl-34470346

RESUMEN

As first explained by the classic Asakura-Oosawa (AO) model, effective attractive forces between colloidal particles induced by depletion of nonadsorbing polymers can drive demixing of colloid-polymer mixtures into colloid-rich and colloid-poor phases, with practical relevance for purification of water, stability of foods and pharmaceuticals, and macromolecular crowding in biological cells. By idealizing polymer coils as effective penetrable spheres, the AO model qualitatively captures the influence of polymer depletion on thermodynamic phase behavior of colloidal suspensions. In previous work, we extended the AO model to incorporate aspherical polymer conformations and showed that fluctuating shapes of random-walk coils can significantly modify depletion potentials [W. K. Lim and A. R. Denton, Soft Matter 12, 2247 (2016); J. Chem. Phys. 144, 024904 (2016)]. We further demonstrated that the shapes of polymers in crowded environments sensitively depend on solvent quality [W. J. Davis and A. R. Denton, J. Chem. Phys. 149, 124901 (2018)]. Here, we apply Monte Carlo simulation to analyze the influence of solvent quality on depletion potentials in mixtures of hard-sphere colloids and nonadsorbing polymer coils, modeled as ellipsoids whose principal radii fluctuate according to random-walk statistics. We consider both self-avoiding and non-self-avoiding random walks, corresponding to polymers in good and theta solvents, respectively. Our simulation results demonstrate that depletion of polymers of equal molecular weight induces much stronger attraction between colloids in good solvents than in theta solvents and confirm that depletion interactions are significantly influenced by aspherical polymer conformations.

15.
Arthroscopy ; 37(2): 489-496.e1, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-33080333

RESUMEN

PURPOSE: To evaluate functional, symptomatic, and diagnostic imaging outcomes after arthroscopic superior capsular reconstruction (SCR) using dermal allograft in patients with massive irreparable rotator cuff tears. METHODS: From 2015 to 2017, this multicenter study retrospectively evaluated patients undergoing arthroscopic SCR for treatment of symptomatic massive rotator cuff tears. Study criteria included the presence of a massive irreparable rotator cuff tear with retraction to the glenoid without diffuse bipolar cartilage loss, Grade 4 or 5 Hamada classification, and subscapularis pathology that could not be addressed. All SCR procedures were performed with neutral abduction of the arm at the time of implantation. Outcome measures included visual analog pain scale (VAS) score, the American Shoulder and Elbow Surgeons (ASES) score, Single Assessment Numeric Evaluation (SANE) score, and active forward elevation (FE) through 2 years postoperatively. Imaging analyses included radiographs, ultrasound, and magnetic resonance imaging at 6 months and 1 year. RESULTS: Fourteen patients met all study criteria including required follow-up. There were statistically significant improvements in VAS pain (3.3-0.6, P = .001), ASES (55.0-86.5, P < .0001), SANE (33.1-71.5, P < .0001), and active FE (128-172, P = .0005) with mean follow-up of 2.1 years. Twelve patients (86%) met the minimum clinically important difference in VAS pain, ASES, and SANE. Thirteen grafts (93%) had ultrasonographic evidence for vascularity by 1 year postoperatively. There were 2 graft complications (14%) with one (7%) requiring revision to reverse total shoulder arthroplasty. CONCLUSIONS: Arthroscopic SCR using dermal allograft can be a safe and effective treatment option for patients with massive irreparable rotator cuff tears with statistically significant improvements in VAS pain, ASES, SANE, and active FE at 2-years postoperatively, with 93% of grafts demonstrating vascularity at 1-year postoperatively. Neutral abduction of the arm at the time of implantation resulted in positive clinical outcomes and may decrease graft failure rate. LEVEL OF EVIDENCE: Level IV, case series.


Asunto(s)
Aloinjertos/fisiología , Dermis/trasplante , Procedimientos de Cirugía Plástica , Lesiones del Manguito de los Rotadores/cirugía , Adulto , Anciano , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Cuidados Posoperatorios , Complicaciones Posoperatorias/etiología , Periodo Posoperatorio , Cuidados Preoperatorios , Rango del Movimiento Articular , Procedimientos de Cirugía Plástica/efectos adversos , Estudios Retrospectivos , Manguito de los Rotadores/diagnóstico por imagen , Manguito de los Rotadores/patología , Manguito de los Rotadores/cirugía , Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Resultado del Tratamiento , Ultrasonografía
16.
J Infect Dis ; 222(2): 252-262, 2020 06 29.
Artículo en Inglés | MEDLINE | ID: mdl-32052044

RESUMEN

BACKGROUND: A higher proportion of circulating memory CD4+ T cells is associated with prevalent diabetes mellitus in the general population. Given the broad changes in adaptive immunity, including memory T-cell expansion, and rising prevalence of diabetes in the human immunodeficiency virus (HIV) population, we assessed whether similar relationships were present in persons with HIV (PWH). METHODS: Multiple CD4+ and CD8+ T-cell subsets were measured by flow cytometry, and prevalent diabetes cases were adjudicated by 2 physicians for PWH and HIV-negative participants in the Veterans Aging Cohort Study. Multivariable logistic regression models evaluated the association of T-cell subsets and diabetes stratified by HIV status, adjusted for cytomegalovirus serostatus and traditional risk factors. RESULTS: Among 2385 participants (65% PWH, 95% male, 68% African American), higher CD45RO+ memory CD4+ T cells and lower CD38+ CD4+ T cells were associated with prevalent diabetes, and had a similar effect size, in both the PWH and HIV-negative (P ≤ .05 for all). Lower CD38+CD8+ T cells were also associated with diabetes in both groups. CONCLUSIONS: The CD4+ and CD8+ T-cell subsets associated with diabetes are similar in PWH and HIV-negative individuals, suggesting that diabetes in PWH may be related to chronic immune activation.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Complicaciones de la Diabetes , Diabetes Mellitus/inmunología , Infecciones por VIH/complicaciones , Infecciones por VIH/inmunología , Memoria Inmunológica , Subgrupos de Linfocitos T/inmunología , Biomarcadores/sangre , Recuento de Linfocito CD4 , Linfocitos T CD8-positivos/inmunología , Estudios de Cohortes , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Análisis de Regresión , Veteranos
17.
MMWR Morb Mortal Wkly Rep ; 69(47): 1777-1781, 2020 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-33237889

RESUMEN

Wearing masks is a CDC-recommended* approach to reduce the spread of SARS-CoV-2, the virus that causes coronavirus disease 2019 (COVID-19), by reducing the spread of respiratory droplets into the air when a person coughs, sneezes, or talks and by reducing the inhalation of these droplets by the wearer. On July 2, 2020, the governor of Kansas issued an executive order† (state mandate), effective July 3, requiring masks or other face coverings in public spaces. CDC and the Kansas Department of Health and Environment analyzed trends in county-level COVID-19 incidence before (June 1-July 2) and after (July 3-August 23) the governor's executive order among counties that ultimately had a mask mandate in place and those that did not. As of August 11, 24 of Kansas's 105 counties did not opt out of the state mandate§ or adopted their own mask mandate shortly before or after the state mandate was issued; 81 counties opted out of the state mandate, as permitted by state law, and did not adopt their own mask mandate. After the governor's executive order, COVID-19 incidence (calculated as the 7-day rolling average number of new daily cases per 100,000 population) decreased (mean decrease of 0.08 cases per 100,000 per day; net decrease of 6%) among counties with a mask mandate (mandated counties) but continued to increase (mean increase of 0.11 cases per 100,000 per day; net increase of 100%) among counties without a mask mandate (nonmandated counties). The decrease in cases among mandated counties and the continued increase in cases in nonmandated counties adds to the evidence supporting the importance of wearing masks and implementing policies requiring their use to mitigate the spread of SARS-CoV-2 (1-6). Community-level mitigation strategies emphasizing wearing masks, maintaining physical distance, staying at home when ill, and enhancing hygiene practices can help reduce transmission of SARS-CoV-2.


Asunto(s)
Infecciones por Coronavirus/epidemiología , Máscaras , Neumonía Viral/epidemiología , Salud Pública/legislación & jurisprudencia , COVID-19 , Infecciones por Coronavirus/prevención & control , Infecciones por Coronavirus/transmisión , Humanos , Incidencia , Kansas/epidemiología , Pandemias/prevención & control , Neumonía Viral/prevención & control , Neumonía Viral/transmisión
18.
Am J Emerg Med ; 38(8): 1594-1598, 2020 08.
Artículo en Inglés | MEDLINE | ID: mdl-31522929

RESUMEN

OBJECTIVE: Evaluate an established scribe program on throughput and revenue capture in an Emergency Department (ED) undergoing an EMR transition. METHODS: A prospective cohort design comparing patients managed with and without scribes in an academic ED. Throughput metrics (medians, min) and relative value units (RVUs, means) were collected. Data was evaluated in its entirety (three months), as well as in two subsets: go live (immediate two weeks) and adoption (two weeks post implementation to end). RESULTS: All patients: There was no significant difference in throughput or RVUs during the three month period. During go-live, scribes showed improvement in total RVUs per patient (4.63 vs 4.40, p = 0.048). During adoption, scribed patients had decreased length of stay (LOS, 221 vs 231, p = 0.023). Adults: Door to provider (28 vs 37, p = 0.014) and total RVUs (5.20 vs 4.92, p = 0.042) were improved with scribes in the go-live period. Scribes improved go-live morning and overnight shifts, while lengthening provider to disposition during afternoon shifts. No significant differences were seen in the adoption period, except for increased provider to disposition time overnight with scribes (154 vs 146, p = 0.030). Pediatrics: When all pediatric patients were compared, scribe patients had a decreased professional RVU charge (2.78 vs 2.90, p = 0.037). During go live and adoption, no significant differences were found in any other parameter or subgrouping. CONCLUSIONS: A scribe's ability to mitigate operational inefficiencies introduced by an EMR transition seems limited in an academic hospital. Previous research highlighting the impact of scribes on revenue was not replicated during this study.


Asunto(s)
Técnicos Medios en Salud/estadística & datos numéricos , Eficiencia Organizacional , Registros Electrónicos de Salud , Servicio de Urgencia en Hospital , Flujo de Trabajo , Humanos , Estudios Prospectivos , Escalas de Valor Relativo
19.
J Immunol ; 199(9): 3187-3201, 2017 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-28972094

RESUMEN

Select CMV epitopes drive life-long CD8+ T cell memory inflation, but the extent of CD4 memory inflation is poorly studied. CD4+ T cells specific for human CMV (HCMV) are elevated in HIV+ HCMV+ subjects. To determine whether HCMV epitope-specific CD4+ T cell memory inflation occurs during HIV infection, we used HLA-DR7 (DRB1*07:01) tetramers loaded with the glycoprotein B DYSNTHSTRYV (DYS) epitope to characterize circulating CD4+ T cells in coinfected HLA-DR7+ long-term nonprogressor HIV subjects with undetectable HCMV plasma viremia. DYS-specific CD4+ T cells were inflated among these HIV+ subjects compared with those from an HIV- HCMV+ HLA-DR7+ cohort or with HLA-DR7-restricted CD4+ T cells from the HIV-coinfected cohort that were specific for epitopes of HCMV phosphoprotein-65, tetanus toxoid precursor, EBV nuclear Ag 2, or HIV gag protein. Inflated DYS-specific CD4+ T cells consisted of effector memory or effector memory-RA+ subsets with restricted TCRß usage and nearly monoclonal CDR3 containing novel conserved amino acids. Expression of this near-monoclonal TCR in a Jurkat cell-transfection system validated fine DYS specificity. Inflated cells were polyfunctional, not senescent, and displayed high ex vivo levels of granzyme B, CX3CR1, CD38, or HLA-DR but less often coexpressed CD38+ and HLA-DR+ The inflation mechanism did not involve apoptosis suppression, increased proliferation, or HIV gag cross-reactivity. Instead, the findings suggest that intermittent or chronic expression of epitopes, such as DYS, drive inflation of activated CD4+ T cells that home to endothelial cells and have the potential to mediate cytotoxicity and vascular disease.


Asunto(s)
Linfocitos T CD4-Positivos/inmunología , Infecciones por Citomegalovirus/inmunología , Citomegalovirus/inmunología , Epítopos de Linfocito T/inmunología , Infecciones por VIH/inmunología , VIH-1/inmunología , Proteínas Virales/inmunología , ADP-Ribosil Ciclasa 1/inmunología , Linfocitos T CD4-Positivos/patología , Infecciones por Citomegalovirus/patología , Femenino , Infecciones por VIH/patología , Antígeno HLA-DR7/inmunología , Humanos , Memoria Inmunológica , Masculino , Glicoproteínas de Membrana/inmunología
20.
Arthroscopy ; 35(12): 3194-3202, 2019 12.
Artículo en Inglés | MEDLINE | ID: mdl-31785745

RESUMEN

PURPOSE: To assess postoperative changes in the thickness of the dermal allograft of the superior capsular reconstruction (SCR) and to evaluate the graft for the presence of intrasubstance pulsatile vessels. METHODS: A retrospective chart review was conducted to identify SCR patients who had ultrasound evaluations between May 2014 and February 2019. Data were collected and stratified based on time from surgery into 2 groups: 0 to 12 months and past the 12-month follow-up. The primary outcome measure was graft thickness at the articular margin-greater tuberosity interface (tuberosity measurement). Secondary measures included midsubstance graft thicknesses 0.5, 1.0, and 1.5 cm medial to the tuberosity measurement; status of lateral graft fixation; presence of pulsatile vessels; and American Shoulder and Elbow Society and visual analog scale scores. RESULTS: Eighteen patients were included for analysis. The tuberosity measurement at final follow-up (mean 25 months, range 12-40 months) was (mean ± standard error [95% confidence interval (CI)]) 4.4 ± 0.2 mm (95% CI 4.0-4.8). This differed significantly from the midsubstance measurements: 0.5 cm: 3.6 ± 0.2 mm (95% CI 3.3-4.0, P = .008); 1.0 cm: 3.1 ± 0.2 mm (95% CI 2.7-3.4, P < .001); and 1.5 cm: 2.9 ± 0.2 mm (95% CI 2.6-3.2, P < .001). Ten constructs (56%) showed signs of pulsatile vessels in the first 12 months and all constructs were intact. ASES scores improved from 49.3 ± 4.0 (95% CI 41.6-57.1) preoperatively to 85.1 ± 2.9 (95% CI 79.4-90.8) (P < .001), and VAS scores decreased from 5.3 ± 0.6 (95% CI 4.2-6.5) preoperatively to 0.9 ± 0.3 (95% CI 0.3-1.5) at final follow-up (P < .001). CONCLUSIONS: The SCR dermal allograft significantly thickens at its lateral aspect, presents with evidence of vasculature in most patients in the first year of implantation, and is not resorbed by the body. LEVEL OF EVIDENCE: Level IV - therapeutic case series.


Asunto(s)
Aloinjertos , Artroplastia/métodos , Lesiones del Manguito de los Rotadores/cirugía , Trasplante de Piel/métodos , Adulto , Anciano , Aloinjertos/irrigación sanguínea , Aloinjertos/patología , Análisis de Varianza , Artroscopía/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Rango del Movimiento Articular , Estudios Retrospectivos , Lesiones del Manguito de los Rotadores/diagnóstico por imagen , Articulación del Hombro/cirugía , Ultrasonografía
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