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1.
Cell ; 186(19): 4189-4203.e22, 2023 09 14.
Artículo en Inglés | MEDLINE | ID: mdl-37633268

RESUMEN

Thrombopoietin (THPO or TPO) is an essential cytokine for hematopoietic stem cell (HSC) maintenance and megakaryocyte differentiation. Here, we report the 3.4 Å resolution cryoelectron microscopy structure of the extracellular TPO-TPO receptor (TpoR or MPL) signaling complex, revealing the basis for homodimeric MPL activation and providing a structural rationalization for genetic loss-of-function thrombocytopenia mutations. The structure guided the engineering of TPO variants (TPOmod) with a spectrum of signaling activities, from neutral antagonists to partial- and super-agonists. Partial agonist TPOmod decoupled JAK/STAT from ERK/AKT/CREB activation, driving a bias for megakaryopoiesis and platelet production without causing significant HSC expansion in mice and showing superior maintenance of human HSCs in vitro. These data demonstrate the functional uncoupling of the two primary roles of TPO, highlighting the potential utility of TPOmod in hematology research and clinical HSC transplantation.


Asunto(s)
Receptores de Trombopoyetina , Trombopoyetina , Animales , Humanos , Ratones , Ciclo Celular , Microscopía por Crioelectrón , Receptores de Trombopoyetina/genética , Trombopoyesis , Metilación de ADN
2.
Mol Cell ; 84(10): 1995-2005.e7, 2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38614096

RESUMEN

Cytokines regulate immune responses by binding to cell surface receptors, including the common subunit beta (ßc), which mediates signaling for GM-CSF, IL-3, and IL-5. Despite known roles in inflammation, the structural basis of IL-5 receptor activation remains unclear. We present the cryo-EM structure of the human IL-5 ternary receptor complex, revealing architectural principles for IL-5, GM-CSF, and IL-3. In mammalian cell culture, single-molecule imaging confirms hexameric IL-5 complex formation on cell surfaces. Engineered chimeric receptors show that IL-5 signaling, as well as IL-3 and GM-CSF, can occur through receptor heterodimerization, obviating the need for higher-order assemblies of ßc dimers. These findings provide insights into IL-5 and ßc receptor family signaling mechanisms, aiding in the development of therapies for diseases involving deranged ßc signaling.


Asunto(s)
Microscopía por Crioelectrón , Factor Estimulante de Colonias de Granulocitos y Macrófagos , Interleucina-3 , Multimerización de Proteína , Receptores de Interleucina-5 , Transducción de Señal , Humanos , Sitios de Unión , Subunidad beta Común de los Receptores de Citocinas/metabolismo , Subunidad beta Común de los Receptores de Citocinas/genética , Subunidad beta Común de los Receptores de Citocinas/química , Factor Estimulante de Colonias de Granulocitos y Macrófagos/metabolismo , Factor Estimulante de Colonias de Granulocitos y Macrófagos/química , Factor Estimulante de Colonias de Granulocitos y Macrófagos/genética , Células HEK293 , Interleucina-3/metabolismo , Interleucina-3/química , Interleucina-3/genética , Interleucina-5/metabolismo , Modelos Moleculares , Unión Proteica , Receptores de Interleucina-5/metabolismo , Receptores de Interleucina-5/genética , Receptores de Interleucina-5/química , Imagen Individual de Molécula , Relación Estructura-Actividad
3.
Cell ; 155(5): 1131-40, 2013 Nov 21.
Artículo en Inglés | MEDLINE | ID: mdl-24267892

RESUMEN

The carboxysome is a protein-based organelle for carbon fixation in cyanobacteria, keystone organisms in the global carbon cycle. It is composed of thousands of subunits including hexameric and pentameric proteins that form a shell to encapsulate the enzymes ribulose 1,5-bisphosphate carboxylase/oxygenase and carbonic anhydrase. Here, we describe the stages of carboxysome assembly and the requisite gene products necessary for progression through each. Our results demonstrate that, unlike membrane-bound organelles of eukaryotes, in carboxysomes the interior of the compartment forms first, at a distinct site within the cell. Subsequently, shell proteins encapsulate this procarboxysome, inducing budding and distribution of functional organelles within the cell. We propose that the principles of carboxysome assembly that we have uncovered extend to diverse bacterial microcompartments.


Asunto(s)
Synechococcus/citología , Synechococcus/metabolismo , Proteínas Bacterianas/metabolismo , Ciclo del Carbono , Redes y Vías Metabólicas , Microscopía Electrónica de Transmisión , Microscopía Fluorescente , Mapas de Interacción de Proteínas , Ribulosa-Bifosfato Carboxilasa/metabolismo , Synechococcus/crecimiento & desarrollo
4.
Nature ; 609(7927): 622-629, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-35863378

RESUMEN

The IL-17 family of cytokines and receptors have central roles in host defence against infection and development of inflammatory diseases1. The compositions and structures of functional IL-17 family ligand-receptor signalling assemblies remain unclear. IL-17E (also known as IL-25) is a key regulator of type 2 immune responses and driver of inflammatory diseases, such as allergic asthma, and requires both IL-17 receptor A (IL-17RA) and IL-17RB to elicit functional responses2. Here we studied IL-25-IL-17RB binary and IL-25-IL-17RB-IL-17RA ternary complexes using a combination of cryo-electron microscopy, single-molecule imaging and cell-based signalling approaches. The IL-25-IL-17RB-IL-17RA ternary signalling assembly is a C2-symmetric complex in which the IL-25-IL-17RB homodimer is flanked by two 'wing-like' IL-17RA co-receptors through a 'tip-to-tip' geometry that is the key receptor-receptor interaction required for initiation of signal transduction. IL-25 interacts solely with IL-17RB to allosterically promote the formation of the IL-17RB-IL-17RA tip-to-tip interface. The resulting large separation between the receptors at the membrane-proximal level may reflect proximity constraints imposed by the intracellular domains for signalling. Cryo-electron microscopy structures of IL-17A-IL-17RA and IL-17A-IL-17RA-IL-17RC complexes reveal that this tip-to-tip architecture is a key organizing principle of the IL-17 receptor family. Furthermore, these studies reveal dual actions for IL-17RA sharing among IL-17 cytokine complexes, by either directly engaging IL-17 cytokines or alternatively functioning as a co-receptor.


Asunto(s)
Interleucina-17 , Receptores de Interleucina-17 , Microscopía por Crioelectrón , Interleucina-17/química , Interleucina-17/metabolismo , Ligandos , Dominios Proteicos , Multimerización de Proteína , Receptores de Interleucina-17/química , Receptores de Interleucina-17/metabolismo , Receptores de Interleucina-17/ultraestructura , Transducción de Señal , Imagen Individual de Molécula
5.
Anal Chem ; 96(29): 12129-12138, 2024 07 23.
Artículo en Inglés | MEDLINE | ID: mdl-38985547

RESUMEN

As organoids and organ-on-chip (OoC) systems move toward preclinical and clinical applications, there is an increased need for method validation. Using a liquid chromatography-mass spectrometry (LC-MS)-based approach, we developed a method for measuring small-molecule drugs and metabolites in the cell medium directly sampled from liver organoids/OoC systems. The LC-MS setup was coupled to an automatic filtration and filter flush system with online solid-phase extraction (SPE), allowing for robust and automated sample cleanup/analysis. For the matrix, rich in, e.g., protein, salts, and amino acids, no preinjection sample preparation steps (protein precipitation, SPE, etc.) were necessary. The approach was demonstrated with tolbutamide and its liver metabolite, 4-hydroxytolbutamide (4HT). The method was validated for analysis of cell media of human stem cell-derived liver organoids cultured in static conditions and on a microfluidic platform according to Food and Drug Administration (FDA) guidelines with regards to selectivity, matrix effects, accuracy, precision, etc. The system allows for hundreds of injections without replacing chromatography hardware. In summary, drug/metabolite analysis of organoids/OoCs can be performed robustly with minimal sample preparation.


Asunto(s)
Hígado , Organoides , Humanos , Organoides/metabolismo , Organoides/citología , Cromatografía Liquida/métodos , Hígado/metabolismo , Espectrometría de Masas/métodos , Tolbutamida/metabolismo , Tolbutamida/análisis , Dispositivos Laboratorio en un Chip , Preparaciones Farmacéuticas/metabolismo , Preparaciones Farmacéuticas/análisis , Extracción en Fase Sólida , Bibliotecas de Moléculas Pequeñas/análisis , Bibliotecas de Moléculas Pequeñas/metabolismo , Bibliotecas de Moléculas Pequeñas/química , Cromatografía Líquida con Espectrometría de Masas
6.
Exp Eye Res ; 242: 109884, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38570181

RESUMEN

Recent studies in rabbits and case reports in humans have demonstrated the efficacy of topical losartan in the treatment of corneal scarring fibrosis after a wide range of injuries, including chemical burns, infections, surgical complications, and some diseases. It is hypothesized that the effect of losartan on the fibrotic corneal stroma occurs through a two-phase process in which losartan first triggers the elimination of myofibroblasts by directing their apoptosis via inhibition of extracellular signal-regulated kinase (ERK)-mediated signal transduction, and possibly through signaling effects on the viability and development of corneal fibroblast and fibrocyte myofibroblast precursor cells. This first step likely occurs within a week or two in most corneas with fibrosis treated with topical losartan, but the medication must be continued for much longer until the epithelial basement membrane (EBM) is fully regenerated or new myofibroblasts will develop from precursor cells. Once the myofibroblasts are eliminated from the fibrotic stroma, corneal fibroblasts can migrate into the fibrotic tissue and reabsorb/reorganize the disordered extracellular matrix (ECM) previously produced by the myofibroblasts. This second stage is longer and more variable in different eyes of rabbits and humans, and accounts for most of the variability in the time it takes for the stromal opacity to be markedly reduced by topical losartan treatment. Eventually, keratocytes reemerge in the previously fibrotic stromal tissue to fine-tune the collagens and other ECM components and maintain the normal structure of the corneal stroma. The efficacy of losartan in the prevention and treatment of corneal fibrosis suggests that it acts as a surrogate for the EBM, by suppressing TGF beta-directed scarring of the wounded corneal stroma, until control over TGF beta action is re-established by a healed EBM, while also supporting regeneration of the EBM by allowing corneal fibroblasts to occupy the subepithelial stroma in the place of myofibroblasts.


Asunto(s)
Sustancia Propia , Fibrosis , Losartán , Miofibroblastos , Losartán/uso terapéutico , Sustancia Propia/efectos de los fármacos , Sustancia Propia/metabolismo , Sustancia Propia/patología , Fibrosis/tratamiento farmacológico , Humanos , Animales , Miofibroblastos/patología , Miofibroblastos/efectos de los fármacos , Conejos , Enfermedades de la Córnea/tratamiento farmacológico , Enfermedades de la Córnea/patología , Bloqueadores del Receptor Tipo 1 de Angiotensina II , Administración Tópica
7.
Exp Eye Res ; 239: 109794, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38237715

RESUMEN

The purpose of this study was to evaluate transforming growth factor beta (TGFß) isoform localization in rabbit corneas with spontaneous persistent epithelial defects (PEDs) after photorefractive keratectomy (PRK). Four cryofixed corneas from a previously reported series of PEDs in rabbits that had PRK were evaluated with triplex immunohistochemistry (IHC) for TGFß3, myofibroblast marker alpha-smooth muscle actin (α-SMA) and mesenchymal marker vimentin. One cornea had sufficient remaining tissue for triplex IHC for TGFß1, TGFß2, or TGFß3 (each with α-SMA and vimentin) using isoform-specific antibodies. All three TGFß isoforms were detected in the subepithelial stroma at and surrounding the PED. Some of each TGFß isoform co-localized with α-SMA of myofibroblasts, which could be TGFß isoform autocrine production by myofibroblasts or TGFß-1, -2, and -3 binding to these myofibroblasts.


Asunto(s)
Queratectomía Fotorrefractiva , Animales , Conejos , Vimentina/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Sustancia Propia/metabolismo , Córnea/metabolismo , Isoformas de Proteínas/metabolismo , Actinas/metabolismo
8.
EMBO J ; 38(22): e101603, 2019 11 15.
Artículo en Inglés | MEDLINE | ID: mdl-31566781

RESUMEN

Neurexins are presynaptic, cell-adhesion molecules that specify the functional properties of synapses via interactions with trans-synaptic ligands. Neurexins are extensively alternatively spliced at six canonical sites that regulate multifarious ligand interactions, but the structural mechanisms underlying alternative splicing-dependent neurexin regulation are largely unknown. Here, we determined high-resolution structures of the complex of neurexophilin-1 and the second laminin/neurexin/sex-hormone-binding globulin domain (LNS2) of neurexin-1 and examined how alternative splicing at splice site #2 (SS2) regulates the complex. Our data reveal a unique, extensive, neurexophilin-neurexin binding interface that extends the jelly-roll ß-sandwich of LNS2 of neurexin-1 into neurexophilin-1. The SS2A insert of LNS2 augments this interface, increasing the binding affinity of LNS2 for neurexophilin-1. Taken together, our data reveal an unexpected architecture of neurexophilin-neurexin complexes that accounts for the modulation of binding by alternative splicing, which in turn regulates the competition of neurexophilin for neurexin binding with other ligands.


Asunto(s)
Empalme Alternativo , Proteínas de Unión al Calcio/química , Proteínas de Unión al Calcio/metabolismo , Glicoproteínas/química , Glicoproteínas/metabolismo , Laminina/metabolismo , Moléculas de Adhesión de Célula Nerviosa/química , Moléculas de Adhesión de Célula Nerviosa/metabolismo , Neuropéptidos/química , Neuropéptidos/metabolismo , Secuencia de Aminoácidos , Animales , Proteínas de Unión al Calcio/genética , Cristalografía por Rayos X , Glicoproteínas/genética , Ligandos , Ratones , Modelos Moleculares , Moléculas de Adhesión de Célula Nerviosa/genética , Neuropéptidos/genética , Unión Proteica , Conformación Proteica , Dominios Proteicos , Ratas , Homología de Secuencia
9.
J Urol ; 210(4): 678-687, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37490615

RESUMEN

PURPOSE: Glans vascular compromise had previously been considered a rare but devastating complication of the subcoronal incision for inflatable penile prosthesis surgery. Here, we describe the largest series of subcoronal implants to date to assess contemporary complication rates. MATERIALS AND METHODS: A retrospective review of subcoronal prosthesis placements by a single surgeon from Seoul, South Korea, was performed. Patients were randomly assigned either Coloplast Titan or AMS 700 device per institutional practice. RESULTS: A total of 898 patients who underwent subcoronal implants from May 2015 to March 2022 were analyzed. Median follow-up was 41 months (IQR 40). Preoperative patient comorbidities included diabetes (36.6%) and Peyronie's disease (4%). The most common complication was transient distal penile edema (74.7%). Transient incisional paresthesia (20.6%) was more common in patients with diabetes (31.9% vs 13.9%, P < .01). Five cases (0.5%) of distal penile skin necrosis were reported in patients who had previously been circumcised. Of these, 3 were managed successfully with wet-to-dry dressing, 1 required skin grafting, and 1 required device explant. Device infection without incisional compromise occurred in 2 cases (0.2%). There were no instances of glans necrosis or ischemia observed in this cohort. Of the first-time implants (817, 90.9%), most (62.3%) were successfully completed under local anesthetic alone, with the remainder of surgeries completed with the addition of adjunctive conscious sedation. CONCLUSIONS: Subcoronal incision for first-time or revision penile implant surgery is not a risk factor for glans ischemia or necrosis and can be safely completed under local anesthetic with or without conscious sedation.


Asunto(s)
Diabetes Mellitus , Disfunción Eréctil , Enfermedades del Pene , Implantación de Pene , Induración Peniana , Prótesis de Pene , Masculino , Humanos , Prótesis de Pene/efectos adversos , Implantación de Pene/efectos adversos , Anestésicos Locales , Pene/cirugía , Induración Peniana/complicaciones , Enfermedades del Pene/etiología , Enfermedades del Pene/cirugía , Necrosis/etiología , Necrosis/cirugía , Satisfacción del Paciente , Disfunción Eréctil/etiología
10.
Mol Vis ; 29: 68-86, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37287640

RESUMEN

Purpose: To understand which cell types, either alone or in combination, contribute to the assembly of the epithelial basement membrane (BM) during corneal wound healing. Methods: A 3D corneal organotypic model and an in situ rabbit photorefractive keratectomy (PRK) model were used in this study. The 3D corneal organotypic model was established by culturing the rabbit corneal epithelial cells with either corneal fibroblasts or myofibroblasts embedded in collagen type I for 18 days. Corneal fibroblasts were isolated from fresh rabbit corneas, and the myofibroblasts were derived either directly from bone marrow or differentiated from corneal fibroblasts. Immunocytochemistry for alpha-smooth muscle actin (SMA), vimentin, desmin, and vinculin markers confirmed well-differentiated myofibroblasts. Immunohistochemistry was performed in cryofixed sections for BM markers, including laminin alpha-5, laminin beta-3, perlecan, nidogen-1, and collagen type IV. Specimens were also examined with transmission electron microscopy (TEM). Corneas were collected from rabbits after -3 diopter (D) PRK at different time points after surgery, with four corneas at each time point in each group. Cryofixed corneal sections were stained for vimentin, alpha-SMA, and nidogen-1. Results: The formation of an epithelial BM with expression of laminin alpha-5, laminin beta-3, perlecan, nidogen-1, and collagen IV was observed at the interface between the corneal epithelial cells and corneal fibroblasts. TEM images further confirmed the presence of epithelial BM in organotypic cultures of epithelial cells and corneal fibroblasts. No epithelial BM was observed in cultures of corneal epithelial cells and myofibroblasts (cornea or bone marrow derived), corneal epithelial cells alone, or corneal fibroblasts alone. In rabbit corneas after -3D PRK, a strong association was observed between the regenerating epithelial BM and the presence of corneal fibroblasts at the site of epithelial BM generation. Conclusions: The corneal epithelial BM assembly is mediated by epithelial cells in coordination with corneal fibroblasts during wound healing.


Asunto(s)
Laminina , Queratectomía Fotorrefractiva , Animales , Conejos , Laminina/metabolismo , Vimentina/metabolismo , Córnea/metabolismo , Fibroblastos/metabolismo , Cicatrización de Heridas/fisiología , Proteínas de la Matriz Extracelular/metabolismo , Células Epiteliales/metabolismo , Membrana Basal/metabolismo , Sustancia Propia
11.
Electrophoresis ; 44(21-22): 1682-1697, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37574258

RESUMEN

For studying stem cell-derived islet organoids (SC-islets) in an organ-on-chip (OoC) platform, we have developed a reversed-phase liquid chromatography-tandem mass spectrometry (RPLC-MS/MS) method allowing for simultaneous determination of insulin, somatostatin-14, and glucagon, with improved matrix robustness compared to earlier methodology. Combining phenyl/hexyl-C18 separations using 2.1 mm inner diameter LC columns and triple quadrupole mass spectrometry, identification and quantification were secured with negligible variance in retention time and quantifier/qualifier ratios, negligible levels of carryover (<2%), and sufficient precision (±10% RSD) and accuracy (±15% relative error) with and without use of an internal standard. The obtained lower limits of quantification were 0.2 µg/L for human insulin, 0.1 µg/L for somatostatin-14, and 0.05 µg/L for glucagon. The here-developed RPLC-MS/MS method showed that the SC-islets have an insulin response dependent on glucose concentration, and the SC-islets produce and release somatostatin-14 and glucagon. The RPLC-MS/MS method for these peptide hormones was compatible with an unfiltered offline sample collection from SC-islets cultivated on a pumpless, recirculating OoC (rOoC) platform. The SC-islets background secretion of insulin was not significantly different on the rOoC device compared to a standard cell culture well-plate. Taken together, RPLC-MS/MS method is well suited for multi-hormone measurements of SC-islets on an OoC platform.


Asunto(s)
Glucagón , Islotes Pancreáticos , Humanos , Cromatografía Liquida , Espectrometría de Masas en Tándem , Glucosa , Islotes Pancreáticos/fisiología , Insulina , Péptidos , Somatostatina , Organoides , Células Madre
12.
Exp Eye Res ; 230: 109443, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36948438

RESUMEN

Alkali burns are one of the most common injuries used in corneal wound healing studies. Investigators have used different conditions to produce corneal alkali injuries that have varied in sodium hydroxide concentration, application methods, and duration of exposure. A critical factor in the subsequent corneal healing responses, including myofibroblast generation and fibrosis localization, is whether, or not, Descemet's membrane and the endothelium are injured during the initial exposure. After exposures that produce injuries confined to the epithelium and stroma, anterior stromal myofibroblasts and fibrosis are typical, with sparing of the posterior stroma. However, if there is also injury to Descemet's membrane and the endothelium, then myofibroblast generation and fibrosis is noted full corneal thickness, with predilection to the most anterior and most posterior stroma and a tendency for relative sparring of the central stroma that is likely related to the availability of TGF beta from the tears, epithelium, and the aqueous humor. A method is described where a 5 mm diameter circle of Whatman #1 filter paper wetted with only 30 µL of alkali solution is applied for 15 s prior to profuse irrigation in rabbit corneas. When 0.6N, or lower, NaOH is used, then the injury, myofibroblasts, and fibrosis generation are limited to the epithelium and stroma. Use of 0.75N NaOH triggers injury to Descemet's membrane and the corneal endothelium with fibrosis throughout the stroma, but rare corneal neovascularization (CNV) and persistent epithelial defects (PED). Use of 1N NaOH with this method produces greater stromal fibrosis and increased likelihood that CNV and PED will occur in individual corneas.


Asunto(s)
Quemaduras Químicas , Lesiones de la Cornea , Quemaduras Oculares , Animales , Conejos , Sustancia Propia/patología , Álcalis/toxicidad , Quemaduras Químicas/patología , Hidróxido de Sodio/toxicidad , Córnea/patología , Lesiones de la Cornea/patología , Quemaduras Oculares/inducido químicamente , Quemaduras Oculares/patología , Fibrosis , Estándares de Referencia
13.
Exp Eye Res ; 235: 109631, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37633325

RESUMEN

The purpose of this study was to evaluate the localization of TGF beta-3 in situ in unwounded rabbit corneas and corneas that had epithelial-stromal injuries produced by photorefractive keratectomy (PRK) in rabbits and to evaluate the in vitro effects of TGF beta-3 compared to TGF beta-1 on alpha-smooth muscle actin (α-SMA) protein expression and myofibroblast development in corneal fibroblasts. Forty-eight New Zealand white rabbits underwent either -3 diopter (D) or -9D PRK and were studied from one to eight weeks (four corneas in each group at each time point) after surgery with immunohistochemistry for TGF beta-3, laminin alpha-5, and alpha-smooth muscle actin (α-SMA). Rabbit corneal fibroblasts were treated with activated TGF beta-1 and/or TGF beta-3 at different concentrations and duration of exposure and studied with immunocytochemistry for myofibroblast development and the expression of α-SMA using Jess automated Western blotting. TGF beta-3 was detected at high levels in the stroma of unwounded corneas and corneas at one to eight weeks after -3D or -9D PRK, as well as in the epithelium and epithelial basement membrane (EBM). No difference was noted between corneas that healed with and without myofibroblast-mediated fibrosis, although TGF beta-3 was commonly associated with myofibroblasts. TGF beta-3 effects on corneal fibroblasts in vitro were similar to TGF beta-1 in stimulating transition to α-SMA-positive myofibroblasts and promoting α-SMA protein expression. The corneal stromal localization pattern of TGF beta-3 protein in unwounded corneas and corneas after epithelial-stromal injury was found to be higher and different from TGF beta-1 and TGF beta-2 reported in previous studies. TGF beta-3 had similar effects to TGF beta-1 in driving myofibroblast development and α-SMA expression in corneal fibroblasts cultured in medium with 1% fetal bovine serum.


Asunto(s)
Epitelio Corneal , Miofibroblastos , Animales , Conejos , Actinas/metabolismo , Córnea/metabolismo , Sustancia Propia/metabolismo , Epitelio Corneal/metabolismo , Fibroblastos/metabolismo , Miofibroblastos/metabolismo , Factor de Crecimiento Transformador beta/metabolismo , Factor de Crecimiento Transformador beta1/metabolismo
14.
BJU Int ; 131(6): 729-733, 2023 06.
Artículo en Inglés | MEDLINE | ID: mdl-36633050

RESUMEN

OBJECTIVE: To analyse data from patient information forms (PIFs) submitted to the manufacturer of a new three-piece inflatable penile prosthesis (IPP), the Rigicon Infla10®, to summarize early outcomes. METHODS: A retrospective review of PIFs from 319 patients implanted with the IPP between 6 January 2019 and 31 December 2021 was performed to assess device durability and rates of reoperation for infection, mechanical failure or medical reasons. RESULTS: The mean ± sd (range) follow-up was 21.2 ± 11 (5-36) months and the mean ± sd patient age was 58.5 ± 8.7 years. Of the total, 4.4% of devices required removal or revision. Complications included mechanical failure (2.5%) and component migration (0.7%). No infections were observed in this series. One patient (0.4%) required revision for inadequate straightening of Peyronie's disease. Three patients (0.9%) requested device removal because of dissatisfaction. A total of 95.6% of the Rigicon Infla10 devices were free from explant or revision 21 months after the original implant date. Kaplan-Meier analysis showed the rates of cumulative survival of the device at 12, 24, 36 months were 95.6%, 94.7% and 93.7%, respectively. CONCLUSIONS: The vast majority of the early Rigicon Infla10 IPPs implanted prior to January 2022 were included in this retrospective analysis of volunteered PIFs. These early results demonstrate initial durability from reoperation equivalent to that of other contemporary devices.


Asunto(s)
Disfunción Eréctil , Implantación de Pene , Induración Peniana , Prótesis de Pene , Masculino , Humanos , Persona de Mediana Edad , Anciano , Prótesis de Pene/efectos adversos , Estudios Retrospectivos , Implantación de Pene/métodos , Induración Peniana/complicaciones , Reoperación , Satisfacción del Paciente , Diseño de Prótesis , Disfunción Eréctil/etiología
15.
Cell Mol Life Sci ; 79(3): 144, 2022 Feb 21.
Artículo en Inglés | MEDLINE | ID: mdl-35188596

RESUMEN

In the cornea, the epithelial basement membrane (EBM) and corneal endothelial Descemet's basement membrane (DBM) critically regulate the localization, availability and, therefore, the functions of transforming growth factor (TGF)ß1, TGFß2, and platelet-derived growth factors (PDGF) that modulate myofibroblast development. Defective regeneration of the EBM, and notably diminished perlecan incorporation, occurs via several mechanisms and results in excessive and prolonged penetration of pro-fibrotic growth factors into the stroma. These growth factors drive mature myofibroblast development from both corneal fibroblasts and bone marrow-derived fibrocytes, and then the persistence of these myofibroblasts and the disordered collagens and other matrix materials they produce to generate stromal scarring fibrosis. Corneal stromal fibrosis often resolves completely if the inciting factor is removed and the BM regenerates. Similar defects in BM regeneration are likely associated with the development of fibrosis in other organs where perlecan has a critical role in the modulation of signaling by TGFß1 and TGFß2. Other BM components, such as collagen type IV and collagen type XIII, are also critical regulators of TGF beta (and other growth factors) in the cornea and other organs. After injury, BM components are dynamically secreted and assembled through the cooperation of neighboring cells-for example, the epithelial cells and keratocytes for the corneal EBM and corneal endothelial cells and keratocytes for the corneal DBM. One of the most critical functions of these reassembled BMs in all organs is to modulate the pro-fibrotic effects of TGFßs, PDGFs and other growth factors between tissues that comprise the organ.


Asunto(s)
Membrana Basal/patología , Enfermedades de la Córnea/patología , Fibrosis/patología , Proteoglicanos de Heparán Sulfato/deficiencia , Factor de Crecimiento Transformador beta/metabolismo , Animales , Membrana Basal/metabolismo , Enfermedades de la Córnea/genética , Enfermedades de la Córnea/metabolismo , Fibrosis/genética , Fibrosis/metabolismo , Humanos , Factor de Crecimiento Transformador beta/genética
16.
J Sep Sci ; 46(18): e2300440, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37528733

RESUMEN

Ultralow flow LC employs ultra-narrow bore columns and mid-range pL/min to low nL/min flow rates (i.e., ≤20 nL/min). The separation columns that are used under these conditions are typically 2-30 µm in inner diameter. Ultralow flow LC systems allow for exceptionally high sensitivity and frequently high resolution. There has been an increasing interest in the analysis of scarce biological samples, for example, circulating tumor cells, extracellular vesicles, organelles, and single cells, and ultralow flow LC was efficiently applied to such samples. Hence, advances towards dedicated ultralow flow LC instrumentation, technical approaches, and higher throughput (e.g., tens-to-hundreds of single cells analyzed per day) were recently made. Here, we review the types of ultralow flow LC technology, followed by a discussion of selected representative ultralow flow LC applications, focusing on the progress made in bioanalysis of amount-limited samples during the last 10 years. We also discuss several recently reported high-sensitivity applications utilizing flow rates up to 100 nL/min, which are below commonly used nanoLC flow rates. Finally, we discuss the path forward for future developments of ultralow flow LC.


Asunto(s)
Cromatografía Liquida , Cromatografía Liquida/métodos
17.
J Sep Sci ; 46(15): e2300210, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37269205

RESUMEN

Dried blood spot samples are simple to prepare and transport, enabling safe and accessible diagnostics, both locally and globally. We review dried blood spot samples for clinical analysis, focusing on liquid chromatography-mass spectrometry as a versatile measurement tool for these samples. Dried blood spot samples can provide information for, for example, metabolomics, xenobiotic analysis, and proteomics. Targeted analyses of small molecules are the main application of dried blood spot samples and liquid chromatography-mass spectrometry, but emerging applications include untargeted metabolomics and proteomics. Applications are highly varied, including analyses related to newborn screening, diagnostics and monitoring of disease progression and treatment effects of virtually any disease, as well as studies into the physiology and effects of diet, exercise, xenobiotics, and doping. A range of dried blood spot products and methods are available, and applied liquid chromatography-mass spectrometry instrumentation is varied with regard to liquid chromatography column formats and selectivity. In addition, novel approaches such as on-paper sample preparation (e.g., selective trapping of analytes with paper-immobilized antibodies) are described. We focus on research papers published in the last 5 years.


Asunto(s)
Pruebas con Sangre Seca , Espectrometría de Masas en Tándem , Recién Nacido , Humanos , Espectrometría de Masas en Tándem/métodos , Pruebas con Sangre Seca/métodos , Química Clínica , Cromatografía Liquida/métodos , Manejo de Especímenes
18.
Health Commun ; 38(12): 2559-2569, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-35757977

RESUMEN

Integrating concepts from the communication theory of resilience (CTR) with theories of health information management and media-stimulated interpersonal conversation, this study investigates associations between worry about COVID-19, acquiring health information from government, news, and personal sources, and enactment of resilience processes. Findings from a representative sample (N = 600) of Floridians show that the extent to which people worried that they or their loves ones might contract COVID-19 during the first wave of the pandemic predicted the extent to which they reported getting health information from a range of news (e.g. national and local newspapers) and personal (e.g. family, friends/coworkers) sources. A serial multiple mediator model found that worry about COVID-19 was associated with acquiring information about COVID from news sources, which predicted getting information about COVID from personal sources, which in turn predicted enactment of resilience processes. Discussion centers on the role that emotions as well as information management at multiple levels (e.g. media, close relationships) play in people's attempts to enact resilience in the context of a public health emergency.


Asunto(s)
COVID-19 , Humanos , COVID-19/epidemiología , Pandemias , SARS-CoV-2 , Ansiedad , Comunicación
19.
Health Commun ; : 1-14, 2023 Nov 06.
Artículo en Inglés | MEDLINE | ID: mdl-37927211

RESUMEN

The post-positivist articulation of the theory of communicative disenfranchisement (TCD) asserts that people subjected to disenfranchising talk (DT; talk that discredits, silences, and stereotypes) experience proximal consequences (PCs; reduced agency, perceived credibility, and ability to exercise rights and privileges) and make negative inferences about others' future interactional goals (negative goal inferences [NGIs]). Through the mediators of PCs and NGIs, DT is theorized to lead to more distal health and well-being outcomes. This article developed measures of DT, PCs, and NGIs to test the TCD's post-positivist model in the context of chronic pain. Items were developed and refined in a pilot study. Then, in two validation studies, exploratory and confirmatory factor analyses were conducted and health and well-being outcomes were assessed. Findings offer initial empirical support for the reliability and convergent, divergent, and predictive validity of the DT, PCs, and NGIs measures, as well as the model proposed in the post-positivist articulation of the TCD.

20.
Health Commun ; 38(6): 1136-1145, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-34711082

RESUMEN

Memorable messages oftentimes are associated with hope, can foster anticipatory resilience prior to the experience of disruptive events, and can buffer the negative impact of adverse experiences on mental health. However, associations among memorable messages, engagement in resilience processes, and mental health have not been examined. Drawing from the communication theory of resilience (CTR), analyses of data from 262 Chinese adults suggested that memorable messages provided a sense of agency and pathways - two interrelated but distinct components of dispositional hope - and functioned as a form of anticipatory resilience that was positively associated with outcomes of coping with disruptive life events including mental health, posttraumatic growth, and meaning in life. These associations were mediated by the extent to which individuals engaged in change- and continuity-related resilience processes as outlined in CTR. Findings offer theoretical implications for memorable message and resilience research as well as practical implications for communicative strategies that can cultivate anticipatory resilience, promote positive adaptation, learning, and reflection, and mitigate the negative effects that disruptive events can have on mental health.


Asunto(s)
Comunicación , Salud Mental , Adulto , Humanos , Adaptación Psicológica , Conocimientos, Actitudes y Práctica en Salud , Personalidad
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