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1.
Sci Transl Med ; 16(744): eadd8273, 2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38657023

RESUMEN

Rotator cuff injuries result in more than 500,000 surgeries annually in the United States, many of which fail. These surgeries typically involve repair of the injured tendon and removal of the subacromial bursa, a synovial-like tissue that sits between the rotator cuff and the acromion. The subacromial bursa has been implicated in rotator cuff pathogenesis and healing. Using proteomic profiling of bursa samples from nine patients with rotator cuff injury, we show that the bursa responds to injury in the underlying tendon. In a rat model of supraspinatus tenotomy, we evaluated the bursa's effect on the injured supraspinatus tendon, the uninjured infraspinatus tendon, and the underlying humeral head. The bursa protected the intact infraspinatus tendon adjacent to the injured supraspinatus tendon by maintaining its mechanical properties and protected the underlying humeral head by maintaining bone morphometry. The bursa promoted an inflammatory response in injured rat tendon, initiating expression of genes associated with wound healing, including Cox2 and Il6. These results were confirmed in rat bursa organ cultures. To evaluate the potential of the bursa as a therapeutic target, polymer microspheres loaded with dexamethasone were delivered to the intact bursae of rats after tenotomy. Dexamethasone released from the bursa reduced Il1b expression in injured rat supraspinatus tendon, suggesting that the bursa could be used for drug delivery to reduce inflammation in the healing tendon. Our findings indicate that the subacromial bursa contributes to healing in underlying tissues of the shoulder joint, suggesting that its removal during rotator cuff surgery should be reconsidered.


Asunto(s)
Bolsa Sinovial , Ratas Sprague-Dawley , Lesiones del Manguito de los Rotadores , Manguito de los Rotadores , Tendones , Cicatrización de Heridas , Animales , Lesiones del Manguito de los Rotadores/patología , Lesiones del Manguito de los Rotadores/metabolismo , Lesiones del Manguito de los Rotadores/cirugía , Humanos , Bolsa Sinovial/patología , Bolsa Sinovial/metabolismo , Tendones/patología , Tendones/metabolismo , Masculino , Manguito de los Rotadores/patología , Ratas , Dexametasona/farmacología , Dexametasona/uso terapéutico , Femenino
2.
FASEB J ; 38(6): e23568, 2024 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-38522021

RESUMEN

The development of musculoskeletal tissues such as tendon, enthesis, and bone relies on proliferation and differentiation of mesenchymal progenitor cells. Gli1+ cells have been described as putative stem cells in several tissues and are presumed to play critical roles in tissue formation and maintenance. For example, the enthesis, a fibrocartilage tissue that connects tendon to bone, is mineralized postnatally by a pool of Gli1+ progenitor cells. These cells are regulated by hedgehog signaling, but it is unclear if TGFß signaling, necessary for tenogenesis, also plays a role in their behavior. To examine the role of TGFß signaling in Gli1+ cell function, the receptor for TGFß, TbR2, was deleted in Gli1-lineage cells in mice at P5. Decreased TGFß signaling in these cells led to defects in tendon enthesis formation by P56, including defective bone morphometry underlying the enthesis and decreased mechanical properties. Immunohistochemical staining of these Gli1+ cells showed that loss of TGFß signaling reduced proliferation and increased apoptosis. In vitro experiments using Gli1+ cells isolated from mouse tail tendons demonstrated that TGFß controls cell proliferation and differentiation through canonical and non-canonical pathways and that TGFß directly controls the tendon transcription factor scleraxis by binding to its distant enhancer. These results have implications in the development of treatments for tendon and enthesis pathologies.


Asunto(s)
Proteínas Hedgehog , Factor de Crecimiento Transformador beta , Animales , Ratones , Proteínas Hedgehog/genética , Proteína con Dedos de Zinc GLI1/genética , Tendones , Transducción de Señal
3.
Am J Sports Med ; 51(14): 3825-3834, 2023 12.
Artículo en Inglés | MEDLINE | ID: mdl-37897335

RESUMEN

BACKGROUND: Rotator cuff repair is a common orthopaedic procedure, yet the rate of failure to heal after surgery is high. Repair site rupture is due to poor tendon-to-bone healing and lack of regeneration of the native fibrocartilaginous enthesis. During development, the enthesis is formed and mineralized by a pool of progenitors activated by hedgehog signaling. Furthermore, hedgehog signaling drives regenerative enthesis healing in young animals, in contrast to older animals, in which enthesis injuries heal via fibrovascular scar and without participation of hedgehog signaling. HYPOTHESIS: Hedgehog activation improves tendon-to-bone healing in an animal model of rotator cuff repair. STUDY DESIGN: Controlled laboratory study. METHODS: A total of 78 adult Sprague-Dawley rats were used. Supraspinatus tendon injury and repair were completed bilaterally, with microsphere-encapsulated hedgehog agonist administered to right shoulders and control microspheres administered to left shoulders. Animals were sacrificed after 3, 14, 28, or 56 days. Gene expression and histological, biomechanical, and bone morphometric analyses were conducted. RESULTS: At 3 days, hedgehog signaling pathway genes Gli1 (1.70; P = .029) and Smo (2.06; P = .0173), as well as Runx2 (1.69; P = .0386), a transcription factor of osteogenesis, were upregulated in treated relative to control repairs. At 14 days, transcription factors of tenogenesis, Scx (4.00; P = .041), and chondrogenesis, Sox9 (2.95; P = .010), and mineralized fibrocartilage genes Col2 (3.18; P = .031) and Colx (1.85; P = .006), were upregulated in treated relative to control repairs. Treatment promoted fibrocartilage formation at the healing interface by 28 days, with improvements in tendon-bone maturity, organization, and continuity. Treatment led to improved biomechanical properties. The material property strength (2.43 vs 1.89 N/m2; P = .046) and the structural property work to failure (29.01 vs 18.09 mJ; P = .030) were increased in treated relative to control repairs at 28 days and 56 days, respectively. Treatment had a marginal effect on bone morphometry underlying the repair. Trabecular thickness (0.08 vs 0.07 mm; P = .035) was increased at 28 days. CONCLUSION: Hedgehog agonist treatment activated hedgehog signaling at the tendon-to-bone repair site and prompted increased mineralized fibrocartilage production. This extracellular matrix production and mineralization resulted in improved biomechanical properties, demonstrating the therapeutic potential of hedgehog agonism for improving tendon-to-bone healing after rotator cuff repair. CLINICAL RELEVANCE: This study demonstrates the therapeutic potential of hedgehog agonist treatment for improving tendon-to-bone healing after rotator cuff injury and repair.


Asunto(s)
Lesiones del Manguito de los Rotadores , Manguito de los Rotadores , Ratas , Animales , Manguito de los Rotadores/patología , Proteínas Hedgehog/metabolismo , Proteínas Hedgehog/farmacología , Cicatrización de Heridas , Ratas Sprague-Dawley , Tendones/cirugía , Lesiones del Manguito de los Rotadores/tratamiento farmacológico , Lesiones del Manguito de los Rotadores/cirugía , Fenómenos Biomecánicos
4.
bioRxiv ; 2023 Jul 02.
Artículo en Inglés | MEDLINE | ID: mdl-37425730

RESUMEN

Rotator cuff injuries result in over 500,000 surgeries performed annually, an alarmingly high number of which fail. These procedures typically involve repair of the injured tendon and removal of the subacromial bursa. However, recent identification of a resident population of mesenchymal stem cells and inflammatory responsiveness of the bursa to tendinopathy indicate an unexplored biological role of the bursa in the context of rotator cuff disease. Therefore, we aimed to understand the clinical relevance of bursa-tendon crosstalk, characterize the biologic role of the bursa within the shoulder, and test the therapeutic potential for targeting the bursa. Proteomic profiling of patient bursa and tendon samples demonstrated that the bursa is activated by tendon injury. Using a rat to model rotator cuff injury and repair, tenotomy-activated bursa protected the intact tendon adjacent to the injured tendon and maintained the morphology of the underlying bone. The bursa also promoted an early inflammatory response in the injured tendon, initiating key players in wound healing. In vivo results were supported by targeted organ culture studies of the bursa. To examine the potential to therapeutically target the bursa, dexamethasone was delivered to the bursa, prompting a shift in cellular signaling towards resolution of inflammation in the healing tendon. In conclusion, contrary to current clinical practice, the bursa should be retained to the greatest extent possible and provides a new therapeutically target for improving tendon healing outcomes. One Sentence Summary: The subacromial bursa is activated by rotator cuff injury and regulates the paracrine environment of the shoulder to maintain the properties of the underlying tendon and bone.

5.
Int Immunopharmacol ; 115: 109635, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-36580758

RESUMEN

The therapeutic benefits of curcuminoids in various diseases have been extensively reported. However, little is known regarding their preventive effects on extensive immunosuppression. We investigated the immunoregulatory effects of a curcuminoid complex (CS/M), solubilized with stevioside, using a microwave-assisted method in a cyclophosphamide (CTX)-induced immunosuppressive mouse model and identified its new pharmacological benefits. CTX-treated mice showed a decreased number of innate cells, such as dendritic cells (DCs), neutrophils, and natural killer (NK) cells, and adaptive immune cells (CD4 and CD8 T cells) in the spleen. In addition, CTX administration decreased T cell activation, especially that of Th1 and CD8 T cells, whereas it increased Th2 and regulatory T (Treg) cell activations. Pre-exposure of CS/M to CTX-induced immunosuppressed mice restored the number of innate cells (DCs, neutrophils, and NK cells) and increased their activity (including the activity of macrophages). Exposure to CS/M also led to the superior restoration of T cell numbers, including Th1, activated CD8 T cells, and multifunctional T cells, suppressed by CTX, along with a decrease in Th2 and Treg cells. Furthermore,CTX-injected mice pre-exposed to CS/M were accompanied by an increase in the levels of antioxidant enzymes (superoxide dismutase, catalase, and glutathione peroxidase), which play an essential role against oxidative stress. Importantly, CS/M treatment significantly reduced viral loads in severe acute respiratory syndrome coronavirus2-infected hamsters and attenuated the gross pathology in the lungs. These results provide new insights into the immunological properties of CS/M in preventing extensive immunosuppression and offer new therapeutic opportunities against various cancers and infectious diseases caused by viruses and intracellular bacteria.


Asunto(s)
COVID-19 , Reconstitución Inmune , Animales , Ratones , Antioxidantes/uso terapéutico , SARS-CoV-2 , Terapia de Inmunosupresión/métodos
6.
Sci Adv ; 7(26)2021 06.
Artículo en Inglés | MEDLINE | ID: mdl-34172438

RESUMEN

Bacterial infections involving joints and vital organs represent a challenging clinical problem because of the two concurrent therapeutic goals of bacterial eradication and tissue preservation. In the case of septic arthritis, permanent destruction of articular cartilage by intense host inflammation is commonly seen even after successful treatment of bacterial infection. Here, we provide scientific evidence of a novel treatment modality that can protect articular cartilage and enhanced eradication of causative bacteria in septic arthritis. Locally delivered cell-penetrating antibiotics such as rifampicin effectively eradicate intracellular reservoirs of methicillin-resistant Staphylococcus aureus within joint cells. Furthermore, mitigation of intra-articular inflammation by targeting the NLRP3 (nucleotide-binding oligomerization domain-, leucine-rich repeat- and pyrin domain-containing 3) inflammasome protects articular cartilage from damage in a murine model of knee septic arthritis. Together, concurrent mitigation of intra-articular inflammation and local adjuvant targeting of intracellular bacteria represents a promising new therapeutic strategy for septic arthritis.


Asunto(s)
Artritis Infecciosa , Staphylococcus aureus Resistente a Meticilina , Infecciones Estafilocócicas , Animales , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Artritis Infecciosa/tratamiento farmacológico , Artritis Infecciosa/microbiología , Inflamación/tratamiento farmacológico , Ratones , Infecciones Estafilocócicas/tratamiento farmacológico
7.
Am J Sports Med ; 49(3): 780-789, 2021 03.
Artículo en Inglés | MEDLINE | ID: mdl-33507808

RESUMEN

BACKGROUND: More than 450,000 rotator cuff repairs are performed annually, yet healing of tendon to bone often fails. This failure is rooted in the fibrovascular healing response, which does not regenerate the native attachment site. Better healing outcomes may be achieved by targeting inflammation during the early period after repair. Rather than broad inhibition of inflammation, which may impair healing, the current study utilized a molecularly targeted approach to suppress IKKß, shutting down only the inflammatory arm of the nuclear factor κB (NF-κB) signaling pathway. PURPOSE: To evaluate the therapeutic potential of IKKß inhibition in a clinically relevant model of rat rotator cuff repair. STUDY DESIGN: Controlled laboratory study. METHODS: After validating the efficacy of the IKKß inhibitor in vitro, it was administered orally once a day for 7 days after surgery in a rat rotator cuff repair model. The effect of treatment on reducing inflammation and improving repair quality was evaluated after 3 days and 2, 4, and 8 weeks of healing, using gene expression, biomechanics, bone morphometry, and histology. RESULTS: Inhibition of IKKß attenuated cytokine and chemokine production in vitro, demonstrating the potential for this inhibitor to reduce inflammation in vivo. Oral treatment with IKKß inhibitor reduced NF-κB target gene expression by up to 80% compared with a nontreated group at day 3, with a subset of these genes suppressed through 14 days. Furthermore, the IKKß inhibitor led to enhanced tenogenesis and extracellular matrix production, as demonstrated by gene expression and histological analyses. At 4 weeks, inhibitor treatment led to increased toughness, no effects on failure load and strength, and decreases in stiffness and modulus when compared with vehicle control. At 8 weeks, IKKß inhibitor treatment led to increased toughness, failure load, and strength compared with control animals. IKKß inhibitor treatment prevented the bone loss near the tendon attachment that occurred in repairs in control. CONCLUSION: Pharmacological inhibition of IKKß successfully suppressed excessive inflammation and enhanced tendon-to-bone healing after rotator cuff repair in a rat model. CLINICAL RELEVANCE: The NF-κB pathway is a promising target for enhancing outcomes after rotator cuff repair.


Asunto(s)
Lesiones del Manguito de los Rotadores , Manguito de los Rotadores , Animales , Fenómenos Biomecánicos , Modelos Animales de Enfermedad , Quinasa I-kappa B , Ratas , Manguito de los Rotadores/cirugía , Tendones , Cicatrización de Heridas
8.
Bone Joint Res ; 9(2): 49-59, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32435455

RESUMEN

AIMS: To characterize the intracellular penetration of osteoblasts and osteoclasts by methicillin-resistant Staphylococcus aureus (MRSA) and the antibiotic and detergent susceptibility of MRSA in bone. METHODS: Time-lapse confocal microscopy was used to analyze the interaction of MRSA strain USA300 with primary murine osteoblasts and osteoclasts. The effects of early and delayed antibiotic treatments on intracellular and extracellular bacterial colony formation and cell death were quantified. We tested the effects of cefazolin, gentamicin, vancomycin, tetracycline, rifampicin, and ampicillin, as well as agents used in surgical preparation and irrigation. RESULTS: MRSA infiltrated bone-resident cells within 15 to 30 minutes. Penetration was most effectively prevented with early (i.e. 30 minutes) antibiotic administration. The combined administration of rifampicin with other antibiotics potentiated their protective effects against MRSA-induced cytotoxicity and most significantly reduced extracellular bacterial bioburden. Gentamicin-containing compounds were most effective in reducing intracellular MRSA bioburden. Of the surgical preparation agents evaluated, betadine reduced in vitro MRSA growth to the greatest extent. CONCLUSION: The standard of care for open fractures involves debridement and antibiotics within the first six hours of injury but does not account for the window in which bacteria penetrate cells. Antibiotics must be administered as early as possible after injury or prior to incision to prevent intracellular infestation. Rifampicin can potentiate the capacity of antibiotic regimens to reduce MRSA-induced cytotoxicity.Cite this article: Bone Joint Res. 2020;9(2):49-59.

9.
Sci Transl Med ; 11(481)2019 02 27.
Artículo en Inglés | MEDLINE | ID: mdl-30814338

RESUMEN

Tendon disorders represent the most common musculoskeletal complaint for which patients seek medical attention; inflammation drives tendon degeneration before tearing and impairs healing after repair. Clinical evidence has implicated the nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) pathway as a correlate of pain-free return to function after surgical repair. However, it is currently unknown whether this response is a reaction to or a driver of pathology. Therefore, we aimed to understand the clinically relevant involvement of the NF-κB pathway in tendinopathy, to determine its potential causative roles in tendon degeneration, and to test its potential as a therapeutic candidate. Transcriptional profiling of early rotator cuff tendinopathy identified increases in NF-κB signaling, including increased expression of the regulatory serine kinase subunit IKKß, which plays an essential role in inflammation. Using cre-mediated overexpression of IKKß in tendon fibroblasts, we observed degeneration of mouse rotator cuff tendons and the adjacent humeral head. These changes were associated with increases in proinflammatory cytokines and innate immune cells within the joint. Conversely, genetic deletion of IKKß in tendon fibroblasts partially protected mice from chronic overuse-induced tendinopathy. Furthermore, conditional knockout of IKKß improved outcomes after surgical repair, whereas overexpression impaired tendon healing. Accordingly, targeting of the IKKß/NF-κB pathway in tendon stromal cells may offer previously unidentified therapeutic approaches in the management of human tendon disorders.


Asunto(s)
FN-kappa B/metabolismo , Transducción de Señal , Tendones/metabolismo , Tendones/patología , Enfermedad Aguda , Adulto , Animales , Enfermedad Crónica , Citocinas/metabolismo , Femenino , Fibroblastos/patología , Humanos , Quinasa I-kappa B/metabolismo , Masculino , Ratones , Persona de Mediana Edad , Bibliotecas de Moléculas Pequeñas/farmacología , Células del Estroma/metabolismo , Cicatrización de Heridas , Adulto Joven
10.
Chem Commun (Camb) ; 55(4): 447-450, 2019 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-30474665

RESUMEN

As a robust radioanalytical method for tracking carbonaceous particulates in vivo, polycyclic aromatic hydrocarbons from diesel exhaust were labeled with a radioactive-iodine-tagged pyrene analogue. Single-photon emission computed tomography and biodistribution studies showed high uptake and slow clearance of this matter in the respiratory system, which may underlie its severe toxicity.


Asunto(s)
Hidrocarburos Policíclicos Aromáticos/farmacocinética , Emisiones de Vehículos , Animales , Yodo/química , Ratones , Hidrocarburos Policíclicos Aromáticos/administración & dosificación , Hidrocarburos Policíclicos Aromáticos/síntesis química , Pirenos/química , Distribución Tisular , Tomografía Computarizada de Emisión de Fotón Único
11.
Nanomaterials (Basel) ; 8(9)2018 Aug 26.
Artículo en Inglés | MEDLINE | ID: mdl-30149661

RESUMEN

Increasing concerns regarding the adverse effects of radioactive iodine waste have inspired the development of a highly efficient and sustainable desalination process for the treatment of radioactive iodine-contaminated water. Because of the high affinity of silver towards iodine species, silver nanoparticles immobilized on a cellulose acetate membrane (Ag-CAM) and biogenic silver nanoparticles containing the radiation-resistant bacterium Deinococcus radiodurans (Ag-DR) were developed and investigated for desalination performance in removing radioactive iodines from water. A simple filtration of radioactive iodine using Ag-CAM under continuous in-flow conditions (approximately 1.5 mL/s) provided an excellent removal efficiency (>99%) as well as iodide anion-selectivity. In the bioremediation study, the radioactive iodine was rapidly captured by Ag-DR in the presence of high concentration of competing anions in a short time. The results from both procedures can be visualized by using single-photon emission computed tomography (SPECT) scanning. This work presents a promising desalination method for the removal of radioactive iodine and a practical application model for remediating radioelement-contaminated waters.

12.
Bioorg Med Chem Lett ; 28(17): 2875-2878, 2018 09 15.
Artículo en Inglés | MEDLINE | ID: mdl-30049578

RESUMEN

In this report, we describe the radiosynthesis of a new thiol-targeting prosthetic group for efficient radioactive iodine labeling of biomolecules. Radioiodination using the precursor 3 was performed to obtain 125I-labeled tetrazole 4b with high radiochemical yield (73%) and radiochemical purity. Using the radiolabeled 4b, a single free cysteine containing peptide and human serum albumin were labeled with 125I in modest-to-good radiochemical yields (65-99%) under mildly reactive conditions. A biodistribution study of [125I]7 in normal ICR mice exhibited lower thyroid uptake values than those of 125I-labeled human serum albumin prepared via a traditional radiolabeling method. Thus, [125I]7 could be employed as an effective radiotracer for molecular imaging and biodistribution studies. The results clearly demonstrate that 4b has the potential to be effectively implemented as a prosthetic group in the preparation of radiolabeled biomolecules.


Asunto(s)
Radioisótopos de Yodo/química , Péptidos/química , Albúmina Sérica Humana/química , Compuestos de Sulfhidrilo/farmacología , Relación Dosis-Respuesta a Droga , Humanos , Estructura Molecular , Relación Estructura-Actividad , Compuestos de Sulfhidrilo/síntesis química , Compuestos de Sulfhidrilo/química
13.
Chemosphere ; 207: 649-654, 2018 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-29852464

RESUMEN

To assess the risk posed by a toxic chemical to human health, it is essential to quantify its uptake in a living subject. This study aims to investigate the biological distribution of inhaled polyhexamethylene guanidine (PHMG) aerosol particle, which is known to cause severe pulmonary damage. By labeling with indium-111 (111In), we quantified the uptake of PHMG for up to 7 days after inhalation exposure in rats. The data demonstrate that PHMG is only slowly cleared, with approximately 74% of inhaled particles persisting in the lungs after 168 h. Approximately 5.3% of inhaled particles were also translocated to the liver after 168 h, although the level of redistribution to other tissues, including the kidneys and spleen, was minimal. These observations suggest that large uptake and slow clearance may underlie the fatal inhalation toxicity of PHMG in humans.


Asunto(s)
Aerosoles/química , Desinfectantes/efectos adversos , Exposición por Inhalación/efectos adversos , Animales , Humanos , Masculino , Ratas
14.
J Korean Med Sci ; 33(53): e348, 2018 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-30595687

RESUMEN

We report a case of Middle East respiratory syndrome coronavirus (MERS-CoV) infection in a 61-year-old businessman returning from Kuwait. The patient arrived there on August 16, 2018, developed watery diarrhea on August 28 (day 0), and came back to Korea on September 7 (day 10) as his condition worsened. Upon arrival, he complained of diarrhea and weakness, but denied any respiratory symptoms, and he directly went to visit an emergency room. Chest radiography revealed interstitial infiltrates in the lungs, and he was immediately transferred to an isolation unit. Quantitative real-time PCR analysis of sputum samples taken on day 11 returned positive for MERS-CoV. No secondary MERS-CoV infection was identified among people who had close contact with him. This case underscores the importance of a high index of suspicion of MERS-CoV infection in any febrile patients who present after a trip to the Middle East.


Asunto(s)
Infecciones por Coronavirus/diagnóstico , Alanina Transaminasa/sangre , Aspartato Aminotransferasas/sangre , Infecciones por Coronavirus/virología , Humanos , Kuwait , Leucopenia/etiología , Masculino , Persona de Mediana Edad , Coronavirus del Síndrome Respiratorio de Oriente Medio/genética , Coronavirus del Síndrome Respiratorio de Oriente Medio/aislamiento & purificación , ARN Viral/metabolismo , República de Corea , Esputo/virología , Viaje
15.
Nutrients ; 11(1)2018 Dec 29.
Artículo en Inglés | MEDLINE | ID: mdl-30597968

RESUMEN

Current drugs for the treatment of rheumatoid arthritis-associated bone loss come with concerns about their continued use. Thus, it is necessary to identify natural products with similar effects, but with fewer or no side effects. We determined whether tart cherry (TC) could be used as a supplement to prevent inflammation-mediated bone loss in tumor necrosis factor (TNF)-overexpressing transgenic (TG) mice. TG mice were assigned to a 0%, 5%, or 10% TC diet, with a group receiving infliximab as a positive control. Age-matched wild-type (WT) littermates fed a 0% TC diet were used as a normal control. Mice were monitored by measurement of body weight. Bone health was evaluated via serum biomarkers, microcomputed tomography (µCT), molecular assessments, and mechanical testing. TC prevented TNF-mediated weight loss, while it did not suppress elevated levels of interleukin (IL)-1ß and IL-6. TC also protected bone structure from inflammation-induced bone loss with a reduced ratio of receptor activator of nuclear factor kappa-B ligand (RANKL)/osteoprotegerin (OPG) to a degree comparable to infliximab. Furthermore, unlike with infliximab, TC exhibited a moderate improvement in TNF-mediated decline in bone stiffness. Thus, TC could be used as a prophylactic regimen against future fragility fractures in the context of highly chronic inflammation.


Asunto(s)
Osteoporosis/prevención & control , Prunus avium , Ligando RANK/metabolismo , Factor de Necrosis Tumoral alfa/metabolismo , Animales , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Ratones , Ligando RANK/genética , Factor de Necrosis Tumoral alfa/genética
16.
J Orthop Res ; 35(12): 2658-2666, 2017 12.
Artículo en Inglés | MEDLINE | ID: mdl-28460421

RESUMEN

Osteoclasts play key roles in bone remodeling and pathologic osteolytic disorders such as inflammation, infection, bone implant loosening, rheumatoid arthritis, metastatic bone cancers, and pathological fractures. Osteoclasts are formed by the fusion of monocytes in response to receptor activators of NF-κB-ligand (RANKL) and macrophage colony stimulating factor 1 (M-CSF). Calreticulin (CRT), a commonly known intracellular protein as a calcium-binding chaperone, has an unexpectedly robust anti-osteoclastogenic effect when its recombinant form is applied to osteoclast precursors in vitro or at the site of bone inflammation externally in vivo. Externally applied Calreticulin was internalized inside the cells. It inhibited key pro-osteoclastogenic transcription factors such as c-Fos and nuclear factor of activated T cells, cytoplasmic 1 (NFATc1)-in osteoclast precursor cells that were treated with RANKL in vitro. Recombinant human Calreticulin (rhCRT) inhibited lipopolysaccharide (LPS)-induced inflammatory osteoclastogenesis in the mouse calvarial bone in vivo. Cathepsin K molecular imaging verified decreased Cathepsin K activity when rhCalreticulin was applied at the site of LPS application in vivo. Recombinant forms of intracellular proteins or their derivatives may act as novel extracellular therapeutic agents. We anticipate our findings to be a starting point in unraveling hidden extracellular functions of other intracellular proteins in different cell types of many organs for new therapeutic opportunities. © 2017 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2658-2666, 2017.


Asunto(s)
Resorción Ósea/prevención & control , Calreticulina/uso terapéutico , Osteogénesis/efectos de los fármacos , Clorometilcetonas de Aminoácidos , Animales , Señalización del Calcio/efectos de los fármacos , Calreticulina/farmacología , Línea Celular , Evaluación Preclínica de Medicamentos , Lipopolisacáridos , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Endogámicos NOD , Factores de Transcripción NFATC/antagonistas & inhibidores , Proteómica
17.
Bioorg Med Chem Lett ; 27(14): 3060-3064, 2017 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-28551100

RESUMEN

Sialidases are key virulence factors that remove sialic acid from host cell surface glycans, thus unmasking receptors to facilitate bacterial adherence and colonization. In this study, we report the isolation and characterization of novel inhibitors of the Streptococcus pneumoniae sialidases NanA, NanB, and NanC from Myristica fragrans seeds. Of the isolated compounds (1-12), malabaricone C showed the most pneumococcal sialidases inhibition (IC50 of 0.3µM for NanA, 3.6µM for NanB, and 2.9µM for NanC). These results suggested that malabaricone C and neolignans could be potential agents for combating S. pneumoniae infection agents.


Asunto(s)
Inhibidores Enzimáticos/farmacología , Lignanos/farmacología , Myristica/química , Neuraminidasa/antagonistas & inhibidores , Extractos Vegetales/farmacología , Activación Enzimática/efectos de los fármacos , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/aislamiento & purificación , Concentración 50 Inhibidora , Cinética , Lignanos/química , Lignanos/aislamiento & purificación , Myristica/metabolismo , Neuraminidasa/metabolismo , Extractos Vegetales/química , Extractos Vegetales/aislamiento & purificación , Isoformas de Proteínas/antagonistas & inhibidores , Isoformas de Proteínas/metabolismo , Resorcinoles/síntesis química , Resorcinoles/aislamiento & purificación , Resorcinoles/farmacología , Semillas/química , Semillas/metabolismo , Streptococcus pneumoniae/efectos de los fármacos , Streptococcus pneumoniae/enzimología
18.
Yonsei Med J ; 57(4): 915-22, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-27189285

RESUMEN

PURPOSE: In childhood cancer survivors, the most common late effect is thyroid dysfunction, most notably subclinical hypothyroidism (SCH). Our study evaluated the risk factors for persistent SCH in survivors. MATERIALS AND METHODS: Survivors (n=423) were defined as patients who survived at least 2 years after cancer treatment completion. Thyroid function was assessed at this time and several years thereafter. Two groups of survivors with SCH were compared: those who regained normal thyroid function during the follow-up period (normalized group) and those who did not (persistent group). RESULTS: Overall, 104 of the 423 survivors had SCH. SCH was observed in 26% of brain or nasopharyngeal cancer survivors (11 of 43) and 21.6% of leukemia survivors (35 of 162). Sixty-two survivors regained normal thyroid function, 30 remained as persistent SCH, and 12 were lost to follow-up. The follow-up duration was 4.03 (2.15-5.78) years. Brain or nasopharyngeal cancer and Hodgkin disease were more common in the persistent group than in the normalized group (p=0.002). More patients in the persistent group received radiation (p=0.008). Radiation to the head region was higher in this group (2394±2469 cGy) than in the normalized group (894±1591 cGy; p=0.003). On multivariable analysis, lymphoma (p=0.011), brain or nasopharyngeal cancer (p=0.039), and head radiation dose ≥1800 cGy (p=0.039) were significant risk factors for persistent SCH. CONCLUSION: SCH was common in childhood cancer survivors. Brain or nasopharyngeal cancer, lymphoma, and head radiation ≥1800 cGy were significant risk factors for persistent SCH.


Asunto(s)
Hipotiroidismo/diagnóstico , Hipotiroidismo/etiología , Neoplasias/complicaciones , Sobrevivientes , Factores de Edad , Niño , Preescolar , Femenino , Humanos , Hipotiroidismo/mortalidad , Lactante , Masculino , Neoplasias/mortalidad , Neoplasias/terapia , Estudios Retrospectivos , Factores de Riesgo
19.
Yonsei Med J ; 57(3): 572-9, 2016 May.
Artículo en Inglés | MEDLINE | ID: mdl-26996554

RESUMEN

PURPOSE: Unique features of adolescent cancer patients include cancer types, developmental stages, and psychosocial issues. In this study, we evaluated the relationship between diagnostic delay and survival to improve adolescent cancer care. MATERIALS AND METHODS: A total of 592 patients aged 0-18 years with eight common cancers were grouped according to age (adolescents, ≥10 years; children, <10 years). We retrospectively reviewed their symptom intervals (SIs, between first symptom/sign of disease and diagnosis), patient delay (PD, between first symptom/sign of disease and first contact with a physician), patient delay proportion (PDP), and overall survival (OS). RESULTS: Mean SI was significantly longer in adolescents than in children (66.4 days vs. 28.4 days; p<0.001), and OS rates were higher in patients with longer SIs (p=0.001). In children with long SIs, OS did not differ according to PDP (p=0.753). In adolescents with long SIs, OS was worse when PDP was ≥0.6 (67.2%) than <0.6 (95.5%, p=0.007). In a multivariate analysis, adolescents in the long SI/PDP ≥0.6 group tended to have a higher hazard ratio (HR, 6.483; p=0.069) than those in the long SI/PDP <0.6 group (HR=1, reference). CONCLUSION: Adolescents with a long SI/PDP ≥0.6 had lower survival rates than those with a short SI/all PDP or a long SI/PDP <0.6. They should be encouraged to seek prompt medical assistance by a physician or oncologist to lessen PDs.


Asunto(s)
Diagnóstico Tardío , Neoplasias/diagnóstico , Neoplasias/mortalidad , Aceptación de la Atención de Salud/estadística & datos numéricos , Adolescente , Niño , Femenino , Humanos , Masculino , Análisis Multivariante , Neoplasias/clasificación , Neoplasias/psicología , Estudios Retrospectivos , Análisis de Supervivencia , Tasa de Supervivencia , Factores de Tiempo
20.
Psychol Sci ; 27(4): 486-501, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26917211

RESUMEN

For 1 to 2 weeks, 5-month-old infants listened at home to one of two novel songs with identical lyrics and rhythms, but different melodies; the song was sung by a parent, emanated from a toy, or was sung live by a friendly but unfamiliar adult first in person and subsequently via interactive video. We then tested the infants' selective attention to two novel individuals after one sang the familiar song and the other sang the unfamiliar song. Infants who had experienced a parent singing looked longer at the new person who had sung the familiar melody than at the new person who had sung the unfamiliar melody, and the amount of song exposure at home predicted the size of that preference. Neither effect was observed, however, among infants who had heard the song emanating from a toy or being sung by a socially unrelated person, despite these infants' remarkable memory for the familiar melody, tested an average of more than 8 months later. These findings suggest that melodies produced live and experienced at home by known social partners carry social meaning for infants.


Asunto(s)
Atención , Desarrollo Infantil , Memoria , Música , Percepción Social , Femenino , Humanos , Lactante , Masculino
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