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1.
ACS Nano ; 2024 May 02.
Artículo en Inglés | MEDLINE | ID: mdl-38695533

RESUMEN

Accurate postoperative assessment of varying mechanical properties is crucial for customizing patient-specific treatments and optimizing rehabilitation strategies following Achilles tendon (AT) rupture and reconstruction surgery. This study introduces a wireless, chip-less, and immune-tolerant in vivo strain-sensing suture designed to continuously monitor mechanical stiffness variations in the reconstructed AT throughout the healing process. This innovative sensing suture integrates a standard medical suturing thread with a wireless fiber strain-sensing system, which incorporates a fiber strain sensor and a double-layered inductive coil for wireless readout. The winding design of Au nanoparticle-based fiber electrodes and a hollow core contribute to the fiber strain sensor's high sensitivity (factor of 6.2 and 15.1 pF for revised sensitivity), negligible hysteresis, and durability over 10,000 stretching cycles. To ensure biocompatibility and immune tolerance during extended in vivo periods, an antibiofouling lubricant layer was applied to the sensing suture. Using this sensing system, we successfully monitored the strain responses of the reconstructed AT in an in vivo porcine model. This facilitated the postoperative assessment of mechanical stiffness variations through a well-established analytical model during the healing period.

2.
Gait Posture ; 111: 48-52, 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38631260

RESUMEN

BACKGROUND: The subtalar joint movement between the talus and calcaneus is restricted in patients with talocalcaneal coalition (TCC). When the motion of the subtalar joint is restricted, shock absorption in the foot decreases, leading to pain during walking. Resection methods to maintain subtalar motion by removing abnormal unions have been proposed. The purpose of this study was to analyze the joint kinematics of patients who underwent TCC resection and to quantitatively evaluate the results of the surgery based on the measured kinematics. METHODS: Joint kinematics of five patients with TCC were obtained using a biplane fluoroscopic imaging system and an intensity-based two-/three-dimensional registration method. The joint kinematics of the tibiotalar and subtalar joints and the tibiocalcaneal motion during the stance phase of walking were obtained. From the kinematics of the hindfoot joints, the inversion/eversion range of motion (ROM) of the patients before and after resection was statistically analyzed using the Wilcoxon signed-rank test to test whether TCC resection improved the ROM. RESULTS: During the loading response period, the eversion ROM of the subtalar joint and tibiocalcaneal motion significantly increased postoperatively. In addition, a significant postoperative increase was observed in the subtalar and tibiocalcaneal inversion ROM during the pre-swing period. SIGNIFICANCE: TCC resection surgery increased the ROM of the subtalar joint, which in turn contributed to the increase in tibiocalcaneal ROM. Increased subtalar and tibiocalcaneal ROM could result in increased shock attenuation and may be a contributing factor to pain relief during walking.

4.
Sci Rep ; 14(1): 5857, 2024 03 11.
Artículo en Inglés | MEDLINE | ID: mdl-38467691

RESUMEN

This study compared muscle strength and foot pressure among patients with metatarsalgia, patients with plantar fasciitis, and healthy controls. A total of 31 patients with foot pain (14 metatarsalgia and 17 plantar fasciitis) and 29 healthy controls participated in the study. The strengths of the plantar flexor and hip muscles were measured using isokinetic and handheld dynamometers, respectively. Foot pressure parameters, including the pressure-time integral (PTI) and foot arch index (AI), were assessed using pedobarography. Compared with the healthy control group, plantar flexor strength was significantly reduced in the affected feet of the metatarsalgia and plantar fasciitis groups (F = 0.083, all p < 0.001); however, hip strength was significantly decreased only in the affected feet of the metatarsalgia group (F = 20.900, p < 0.001). Plantar flexor (p < 0.001) and hip (p = 0.004) strength were significantly lower in the metatarsalgia group than in the plantar fasciitis group. The PTI was lower in the forefeet of the affected feet in the metatarsalgia (p < 0.001) and plantar fasciitis (p = 0.004) groups. Foot AI (p < 0.001) was significantly reduced only in the metatarsalgia group. These results suggest the need to consider the evaluation of muscle strength and foot pressure in both feet for the diagnosis and treatment of foot pain.


Asunto(s)
Fascitis Plantar , Metatarsalgia , Humanos , Pie , Metatarsalgia/terapia , Músculo Esquelético , Fuerza Muscular
5.
Medicina (Kaunas) ; 60(2)2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38399614

RESUMEN

Background and Objectives: Soft tissue sarcomas represent a heterogeneous group of malignant mesenchymal tissues. Despite their low prevalence, soft tissue sarcomas present clinical challenges for orthopedic surgeons owing to their aggressive nature, and perioperative wound infections. However, the low prevalence of soft tissue sarcomas has hindered the availability of large-scale studies. This study aimed to analyze wound infections after wide resection in patients with soft tissue sarcomas by employing big data analytics from the Hub of the Health Insurance Review and Assessment Service (HIRA). Materials and Methods: Patients who underwent wide excision of soft tissue sarcomas between 2010 and 2021 were included. Data were collected from the HIRA database of approximately 50 million individuals' information in the Republic of Korea. The data collected included demographic information, diagnoses, prescribed medications, and surgical procedures. Random forest has been used to analyze the major associated determinants. A total of 10,906 observations with complete data were divided into training and validation sets in an 80:20 ratio (8773 vs. 2193 cases). Random forest permutation importance was employed to identify the major predictors of infection and Shapley Additive Explanations (SHAP) values were derived to analyze the directions of associations with predictors. Results: A total of 10,969 patients who underwent wide excision of soft tissue sarcomas were included. Among the study population, 886 (8.08%) patients had post-operative infections requiring surgery. The overall transfusion rate for wide excision was 20.67% (2267 patients). Risk factors among the comorbidities of each patient with wound infection were analyzed and dependence plots of individual features were visualized. The transfusion dependence plot reveals a distinctive pattern, with SHAP values displaying a negative trend for individuals without blood transfusions and a positive trend for those who received blood transfusions, emphasizing the substantial impact of blood transfusions on the likelihood of wound infection. Conclusions: Using the machine learning random forest model and the SHAP values, the perioperative transfusion, male sex, old age, and low SES were important features of wound infection in soft-tissue sarcoma patients.


Asunto(s)
Sarcoma , Neoplasias de los Tejidos Blandos , Infección de Heridas , Humanos , Masculino , Complicaciones Posoperatorias/etiología , Factores de Riesgo , Seguro de Salud , Sarcoma/cirugía , Sarcoma/complicaciones , Neoplasias de los Tejidos Blandos/complicaciones , Neoplasias de los Tejidos Blandos/patología , Neoplasias de los Tejidos Blandos/cirugía , Estudios Retrospectivos
6.
Bioact Mater ; 34: 164-180, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38343773

RESUMEN

Extracellular matrix (ECM) undergoes dynamic inflation that dynamically changes ligand nanospacing but has not been explored. Here we utilize ECM-mimicking photocontrolled supramolecular ligand-tunable Azo+ self-assembly composed of azobenzene derivatives (Azo+) stacked via cation-π interactions and stabilized with RGD ligand-bearing poly(acrylic acid). Near-infrared-upconverted-ultraviolet light induces cis-Azo+-mediated inflation that suppresses cation-π interactions, thereby inflating liganded self-assembly. This inflation increases nanospacing of "closely nanospaced" ligands from 1.8 nm to 2.6 nm and the surface area of liganded self-assembly that facilitate stem cell adhesion, mechanosensing, and differentiation both in vitro and in vivo, including the release of loaded molecules by destabilizing water bridges and hydrogen bonds between the Azo+ molecules and loaded molecules. Conversely, visible light induces trans-Azo+ formation that facilitates cation-π interactions, thereby deflating self-assembly with "closely nanospaced" ligands that inhibits stem cell adhesion, mechanosensing, and differentiation. In stark contrast, when ligand nanospacing increases from 8.7 nm to 12.2 nm via the inflation of self-assembly, the surface area of "distantly nanospaced" ligands increases, thereby suppressing stem cell adhesion, mechanosensing, and differentiation. Long-term in vivo stability of self-assembly via real-time tracking and upconversion are verified. This tuning of ligand nanospacing can unravel dynamic ligand-cell interactions for stem cell-regulated tissue regeneration.

7.
Int J Mol Sci ; 25(1)2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38203791

RESUMEN

This study reports the effect of the not-calcining process on the bioresorption and biomineralization of hydroxyapatite through in vitro dissolution assessment. The prepared calcined hydroxyapatite (c-HAp) and uncalcined hydroxyapatite (unc-HAp) have a particle size of 2 µm and 13 µm, surface areas of 4.47 m2/g and 108.08 m2/g, and a Ca/P ratio of 1.66 and 1.52, respectively. In vitro dissolution assessments of c-HAp and unc-HAp were performed for 20 days at 37 °C in a citric acid buffer according to ISO 10993-14. During the dissolution, the c-HAp and unc-HAp confirmed an increase in weight, and the calcium and phosphorous ions were rapidly released. The calcium ions released from c-HAp formed rod-shaped particles with a longer and thinner morphology, while in unc-HAp, they appeared thicker and shorter. In the ICP-OES results, the concentrations of calcium elements were initially increased and then decreased by this formation. The rod-shaped particles identified as calcium citrate (Ca-citrate) through the XRD pattern. The calcium content of Ca-citrate particles from unc-HAp was higher than that from c-HAp. The unc-HAp demonstrated non-toxic properties in a cytotoxicity evaluation. Therefore, due to its higher bioresorption and biomineralization, unc-HAp exhibits enhanced biocompatibility compared to c-HAp.


Asunto(s)
Biomineralización , Calcio , Citrato de Calcio , Calcio de la Dieta , Durapatita , Iones
8.
Clin Orthop Surg ; 15(6): 942-952, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-38045586

RESUMEN

Background: This study aimed to evaluate the annual trends of transfusion rates and utilization of blood management agents in total knee arthroplasty (TKA) based on the operation type and to analyze the risk factors of transfusion after TKA. Methods: Using the Korean National Insurance claims database of 797,106 primary and revision TKAs between January 2008 and October 2019, data on the patients' characteristics, comorbidities, utilization of transfusion, and blood management agents were collected. The patients were categorized into three groups based on the operation type: primary, revision, and simultaneous bilateral TKA. The transfusion rate and utilization of blood management agents (intraoperative tranexamic acid [TXA] and preoperative iron supplements) were compared, and the risk factors for transfusion were evaluated. Results: After excluding the inaccurate data, 730,554 arthroplasties (636,292 primary, 10,540 revision, and 41,861 simultaneous bilateral TKAs) were identified. The transfusion rates of primary, revision, and simultaneous bilateral TKAs in 2019 were 64.0%, 67.7%, and 68.9%, respectively, which were significantly decreased compared with 83.2%, 88.0%, and 92.5% in 2008, respectively (p < 0.001). Conversely, the utilization of intraoperative TXA and preoperative iron supplements was significantly increased from 4.6% and 13.8%, respectively, in 2008 to 52.4% and 27.0%, respectively, in 2019 (p < 0.001). The utilization of intraoperative TXA and preoperative iron supplements significantly lowered the risk of transfusion after TKA (odds ratio [OR], 0.20; p < 0.001 and OR, 0.71; p < 0.001). Conclusions: The transfusion rate after TKA decreased gradually from 83.5% to 64.5% between 2008 and 2019 in South Korea corresponding with the increased utilization of blood management agents. Therefore, consistent attention to patient blood management should be emphasized to reduce the transfusion rate after TKA.


Asunto(s)
Antifibrinolíticos , Artroplastia de Reemplazo de Rodilla , Ácido Tranexámico , Humanos , Artroplastia de Reemplazo de Rodilla/efectos adversos , Antifibrinolíticos/uso terapéutico , Ácido Tranexámico/uso terapéutico , Transfusión Sanguínea , Pérdida de Sangre Quirúrgica , Hierro
9.
Sci Rep ; 13(1): 21167, 2023 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-38036595

RESUMEN

Obesity has been increasing in many regions of the world, including Europe, USA, and Korea. To manage obesity, we should consider it as a disease and apply therapeutic methods for its treatment. Molecular and therapeutic approaches for obesity management involve regulating biomolecules such as DNA, RNA, and protein in adipose-derived stem cells to prevent to be fat cells. Multiple factors are believed to play a role in fat differentiation, with one of the most effective factor is Ca2+. We recently reported that the electromagnetic perceptive gene (EPG) regulated intracellular Ca2+ levels under various electromagnetic fields. This study aimed to investigate whether EPG could serve as a therapeutic method against obesity. We confirmed that EPG serves as a modulator of Ca2+ levels in primary adipose cells, thereby regulating several genes such as CasR, PPARγ, GLU4, GAPDH during the adipogenesis. In addition, this study also identified EPG-mediated regulation of myogenesis that myocyte transcription factors (CasR, MyoG, MyoD, Myomaker) were changed in C2C12 cells and satellite cells. In vivo experiments carried out in this study confirmed that total weight/ fat/fat accumulation were decreased and lean mass was increased by EPG with magnetic field depending on age of mice. The EPG could serve as a potent therapeutic agent against obesity.


Asunto(s)
Adipogénesis , Obesidad , Animales , Ratones , Células 3T3-L1 , Adipogénesis/genética , Diferenciación Celular/genética , Fenómenos Electromagnéticos , Desarrollo de Músculos/genética , Obesidad/terapia , PPAR gamma/metabolismo , Proteínas de Peces/farmacología , Proteínas de Peces/uso terapéutico
10.
Int J Mol Sci ; 24(12)2023 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-37372985

RESUMEN

This study reports the preparation of silica-coated and nano-fructosome encapsulated Candida antarctica lipase B particles (CalB@NF@SiO2) and a demonstration of their enzymatic hydrolysis and acylation. CalB@NF@SiO2 particles were prepared as a function of TEOS concentration (3-100 mM). Their mean particle size was 185 nm by TEM. Enzymatic hydrolysis was performed to compare catalytic efficiencies of CalB@NF and CalB@NF@SiO2. The catalytic constants (Km, Vmax, and Kcat) of CalB@NF and CalB@NF@SiO2 were calculated using the Michaelis-Menten equation and Lineweaver-Burk plot. Optimal stability of CalB@NF@SiO2 was found at pH 8 and a temperature of 35 °C. Moreover, CalB@NF@SiO2 particles were reused for seven cycles to evaluate their reusability. In addition, enzymatic synthesis of benzyl benzoate was demonstrated via an acylation reaction with benzoic anhydride. The efficiency of CalB@NF@SiO2 for converting benzoic anhydride to benzyl benzoate by the acylation reaction was 97%, indicating that benzoic anhydride was almost completely converted to benzyl benzoate. Consequently, CalB@NF@SiO2 particles are better than CalB@NF particles for enzymatic synthesis. In addition, they are reusable with high stability at optimal pH and temperature.


Asunto(s)
Enzimas Inmovilizadas , Dióxido de Silicio , Hidrólisis , Proteínas Fúngicas
11.
Clin Orthop Relat Res ; 481(11): 2154-2163, 2023 11 01.
Artículo en Inglés | MEDLINE | ID: mdl-37145140

RESUMEN

BACKGROUND: Osteosarcoma is the most common secondary malignancy among survivors of retinoblastoma. Most previous reports on secondary malignancy of retinoblastoma included all types of secondary malignancies without a focus on osteosarcoma, owing to its rarity. In addition, there are few studies suggesting tools for regular surveillance for early detection. QUESTIONS/PURPOSES: (1) What are the radiologic and clinical characteristics of secondary osteosarcoma after retinoblastoma? (2) What is the clinical survivorship? (3) Is a radionuclide bone scan a reasonable imaging modality for early detection in patients with retinoblastoma? METHODS: Between February 2000 and December 2019, we treated 540 patients for retinoblastoma. Twelve patients (six male, six female) subsequently developed an osteosarcoma in the extremities; two of these patients had two sites of osteosarcoma (10 femurs, four tibiae) . A Technetium-99m bone scan image was examined annually in all patients for regular surveillance after the treatment of retinoblastoma as per our hospital's policy. All patients were treated with the same strategy as that used for primary conventional osteosarcoma, namely neoadjuvant chemotherapy, wide excision, and adjuvant chemotherapy. The median follow-up period was 12 years (range 8 to 21 years). The median age at the time of diagnosis of osteosarcoma was 9 years (range 5 to 15 years), and the median interval from retinoblastoma diagnosis to osteosarcoma diagnosis was 8 years (range 5 to 15 years). Radiologic characteristics were assessed with plain radiographs and MRI, while clinical characteristics were assessed through a retrospective review of medical records. For clinical survivorship, we evaluated overall survival, local recurrence-free survival, and metastasis-free survival. We reviewed the results of bone scans and clinical symptoms at the time of diagnosis for osteosarcoma after retinoblastoma. RESULTS: In nine of 14 patients, the tumor had a diaphyseal center, and five of the tumors were located at the metaphysis. The femur was the most common site (n = 10), followed by the tibia (n = 4). The median tumor size was 9 cm (range 5 to 13 cm). There was no local recurrence after surgical resection of the osteosarcoma, and the 5-year overall survival rate after the diagnosis of osteosarcoma was 86% (95% CI 68% to 100%). In all 14 tumors, the Technetium bone scan showed increased uptake in the lesions. Ten of 14 tumors were examined in clinic because of patient complaints of pain in the affected limb. Four patients showed no clinical symptoms detected by abnormal uptake on bone scan. CONCLUSION: For unclear reasons, secondary osteosarcomas in patients who were alive after the treatment of retinoblastoma had a slight predilection for the diaphysis of the long bone compared with patients with spontaneous osteosarcoma in other reports. The clinical survivorship of osteosarcoma as a secondary malignancy after retinoblastoma may not be inferior to that of conventional osteosarcoma. Close follow-up with at least yearly clinical assessment and bone scans or other imaging modalities appears to be helpful in detecting secondary osteosarcoma after the treatment of patients with retinoblastoma. Larger multi-institutional studies will be needed to substantiate these observations.Level of Evidenc e Level IV, therapeutic study.


Asunto(s)
Neoplasias Óseas , Neoplasias Primarias Secundarias , Osteosarcoma , Neoplasias de la Retina , Retinoblastoma , Humanos , Masculino , Femenino , Preescolar , Niño , Adolescente , Retinoblastoma/diagnóstico por imagen , Retinoblastoma/terapia , Retinoblastoma/complicaciones , Tecnecio , Neoplasias Óseas/diagnóstico por imagen , Neoplasias Óseas/terapia , Neoplasias Óseas/patología , Osteosarcoma/diagnóstico por imagen , Osteosarcoma/terapia , Osteosarcoma/patología , Neoplasias Primarias Secundarias/diagnóstico por imagen , Neoplasias Primarias Secundarias/terapia , Neoplasias Primarias Secundarias/epidemiología , Neoplasias de la Retina/complicaciones , Neoplasias de la Retina/patología , Estudios Retrospectivos
12.
Medicine (Baltimore) ; 102(11): e33310, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36930075

RESUMEN

Extracorporeal shockwave therapy (ESWT) can induce wound healing by increasing tissue microcirculation. However, studies on the effect of ESWT on enhancing tissue microcirculation in diabetic foot ulcer (DFU), particularly on when the microcirculation increases after ESWT application, are still lacking. Therefore, we aimed to examine the effectiveness of ESWT in promoting microcirculation in DFU patients in a time-dependent manner. We included 50 feet of 25 patients with type 2 diabetes mellitus and Wagner grade I to II DFU in this study. The affected feet were used as the ESWT group and the unaffected contralateral feet were used as the control group. ESWT was performed in 3 sessions per week for a total of 3 weeks. Transcutaneous partial oxygen pressure (TcPO2) was used to evaluate the tissue microcirculation. The TcPO2 level (>43 mm Hg) in the ESWT group was recovered by the 2nd week of treatment, and statistical significance (P < .05) was demonstrated at the same time. From the 2nd week of ESWT, a significant increase in TcPO2 was observed in Wagner grade I and II DFU. These findings imply that the ESWT may improve microcirculation in patients with Wagner grades I to II DFU. However, this impact requires at least 2 weeks or more than 6 sessions. For better comparison, further studies with larger clinical groups and extended period are needed.


Asunto(s)
Diabetes Mellitus Tipo 2 , Pie Diabético , Tratamiento con Ondas de Choque Extracorpóreas , Humanos , Pie Diabético/terapia , Estudios Prospectivos , Resultado del Tratamiento , Diabetes Mellitus Tipo 2/complicaciones , Diabetes Mellitus Tipo 2/terapia , Microcirculación
13.
Adv Mater ; 34(49): e2205498, 2022 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-36268986

RESUMEN

Dynamic manipulation of supramolecular self-assembled structures is achieved irreversibly or under non-physiological conditions, thereby limiting their biomedical, environmental, and catalysis applicability. In this study, microgels composed of azobenzene derivatives stacked via π-cation and π-π interactions are developed that are electrostatically stabilized with Arg-Gly-Asp (RGD)-bearing anionic polymers. Lateral swelling of RGD-bearing microgels occurs via cis-azobenzene formation mediated by near-infrared-light-upconverted ultraviolet light, which disrupts intermolecular interactions on the visible-light-absorbing upconversion-nanoparticle-coated materials. Real-time imaging and molecular dynamics simulations demonstrate the deswelling of RGD-bearing microgels via visible-light-mediated trans-azobenzene formation. Near-infrared light can induce in situ swelling of RGD-bearing microgels to increase RGD availability and trigger release of loaded interleukin-4, which facilitates the adhesion structure assembly linked with pro-regenerative polarization of host macrophages. In contrast, visible light can induce deswelling of RGD-bearing microgels to decrease RGD availability that suppresses macrophage adhesion that yields pro-inflammatory polarization. These microgels exhibit high stability and non-toxicity. Versatile use of ligands and protein delivery can offer cytocompatible and photoswitchable manipulability of diverse host cells.


Asunto(s)
Microgeles , Macrófagos
14.
Diagnostics (Basel) ; 12(7)2022 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-35885643

RESUMEN

We thank Dr. Sadettin Ciftci for his comment on the key point issues in measuring the alpha and beta angle with Graf method. We appreciated his feedback [...].

15.
Adv Sci (Weinh) ; 9(18): e2104835, 2022 06.
Artículo en Inglés | MEDLINE | ID: mdl-35460189

RESUMEN

An effective wound management strategy needs accurate assessment of wound status throughout the whole healing process. This can be achieved by examining molecular biomarkers including proteins, DNAs, and RNAs. However, existing methods for quantifying these biomarkers such as immunohistochemistry and quantitative polymerase chain reaction are usually laborious, resource-intensive, and disruptive. This article reports the development and utilization of mRNA nanosensors (i.e., NanoFlare) that are topically applied on cutaneous wounds to reveal the healing status through targeted and semi-quantitative examination of the mRNA biomarkers in skin cells. In 2D and 3D in vitro models, the efficacy and efficiency of these nanosensors are demonstrated in revealing the dynamic changes of mRNA biomarkers for different stages of wound development. In mouse models, this platform permits the tracking and identification of wound healing stages and a normal and diabetic wound healing process by wound healing index in real time.


Asunto(s)
Diabetes Mellitus , Cicatrización de Heridas , Animales , Biomarcadores , Diabetes Mellitus/metabolismo , Ratones , ARN Mensajero/genética , Piel/lesiones , Piel/metabolismo , Cicatrización de Heridas/genética
16.
Adv Mater ; 34(27): e2110340, 2022 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-35476306

RESUMEN

Cell adhesion occurs when integrin recognizes and binds to Arg-Gly-Asp (RGD) ligands present in fibronectin. In this work, submolecular ligand size and spacing are tuned via template-mediated in situ growth of nanoparticles for dynamic macrophage modulation. To tune liganded gold nanoparticle (GNP) size and spacing from 3 to 20 nm, in situ localized assemblies of GNP arrays on nanomagnetite templates are engineered. 3 nm-spaced ligands stimulate the binding of integrin, which mediates macrophage-adhesion-assisted pro-regenerative polarization as compared to 20 nm-spaced ligands, which can be dynamically anchored to the substrate for stabilizing integrin binding and facilitating dynamic macrophage adhesion. Increasing the ligand size from 7 to 20 nm only slightly promotes macrophage adhesion, not observed with 13 nm-sized ligands. Increasing the ligand spacing from 3 to 17 nm significantly hinders macrophage adhesion that induces inflammatory polarization. Submolecular tuning of ligand spacing can dominantly modulate host macrophages.


Asunto(s)
Oro , Nanopartículas del Metal , Adhesión Celular , Fibronectinas , Integrinas/metabolismo , Ligandos
17.
J Am Chem Soc ; 144(13): 5769-5783, 2022 04 06.
Artículo en Inglés | MEDLINE | ID: mdl-35275625

RESUMEN

The receptor-ligand interactions in cells are dynamically regulated by modulation of the ligand accessibility. In this study, we utilize size-tunable magnetic nanoparticle aggregates ordered at both nanometer and atomic scales. We flexibly anchor magnetic nanoparticle aggregates of tunable sizes over the cell-adhesive RGD ligand (Arg-Gly-Asp)-active material surface while maintaining the density of dispersed ligands accessible to macrophages at constant. Lowering the accessible ligand dispersity by increasing the aggregate size at constant accessible ligand density facilitates the binding of integrin receptors to the accessible ligands, which promotes the adhesion of macrophages. In high ligand dispersity, distant magnetic manipulation to lift the aggregates (which increases ligand accessibility) stimulates the binding of integrin receptors to the accessible ligands available under the aggregates to augment macrophage adhesion-mediated pro-healing polarization both in vitro and in vivo. In low ligand dispersity, distant control to drop the aggregates (which decreases ligand accessibility) repels integrin receptors away from the aggregates, thereby suppressing integrin receptor-ligand binding and macrophage adhesion, which promotes inflammatory polarization. Here, we present "accessible ligand dispersity" as a novel fundamental parameter that regulates receptor-ligand binding, which can be reversibly manipulated by increasing and decreasing the ligand accessibility. Limitless tuning of nanoparticle aggregate dimensions and morphology can offer further insight into the regulation of receptor-ligand binding in host cells.


Asunto(s)
Integrinas , Nanopartículas , Adhesión Celular , Integrinas/metabolismo , Ligandos , Macrófagos/metabolismo
18.
Medicine (Baltimore) ; 101(1): e28516, 2022 Jan 07.
Artículo en Inglés | MEDLINE | ID: mdl-35029913

RESUMEN

ABSTRACT: In the pubertal period, bone age advances rapidly in conjunction with growth spurts. Precise bone-age assessments in this period are important, but results from the hand and elbow can be different. We aimed to compare the bone age between the hand and elbow around puberty onset and to elucidate the chronological age confirming puberty onset according to elbow-based bone age.A total of 211 peripubertal subjects (127 boys and 84 girls) who underwent hand and elbow radiographs within 2 months was enrolled. Two radiologists and a pediatric orthopedic surgeon assessed bone age. Hand bone age was graded using the Greulich-Pyle (GP) method, and elbow bone age was determined using the Sauvegrain method. The correlation of 2 methods was evaluated by Demining regression analysis, and the mean absolute difference (MAD) with chronological age was compared between pre-pubertal and pubertal subjects. Receiver-operating characteristic curve analysis was performed to determine the chronological age confirming puberty onset.There was a statistically significant difference in bone age revealed by the GP and Sauvegrain methods in the pubertal group. In the pubertal group, the MAD was 1.26 ±â€Š0.90 years with the GP method and 0.61 ±â€Š0.47 years with the Sauvegrain method in boys (P < .001), while in girls, the MAD was 0.84 ±â€Š0.60 years and 0.53 ±â€Š0.36 years with the same 2 methods (P = .033). The chronological age for confirming puberty onset using the elbow was 12.2 years in boys and 10.3 years in girls.The bone ages of hand and elbow were different at puberty, and the elbow was a more reliable location for bone-age assessment at puberty. Puberty onset according to elbow occurred slightly earlier than expected.


Asunto(s)
Determinación de la Edad por el Esqueleto/métodos , Codo/diagnóstico por imagen , Mano/diagnóstico por imagen , Pubertad , Adolescente , Niño , Articulación del Codo/diagnóstico por imagen , Femenino , Humanos , Masculino
19.
Sci Rep ; 12(1): 610, 2022 01 12.
Artículo en Inglés | MEDLINE | ID: mdl-35022508

RESUMEN

The modified Broström procedure (MBP) is an initial treatment for symptomatic chronic ankle instability (CAI) patients. This study aimed to compare the proprioception and neuromuscular control ability of both affected and unaffected ankles at the time of return to sports after MBP for patients with scores of normal controls. 75 individuals (40 who underwent MBP, 35 normal controls) participated. The dynamic balance test scores were significantly higher in the affected ankle of the patients than in the controls (1.5 ± 0.6° vs. 1.1 ± 0.4°, p < 0.003). The time to peak torque for dorsiflexion (60.8 ± 13.9 ms vs. 52.2 ± 17.5 ms, p < 0.022) and eversion (68.9 ± 19.1 ms vs. 59.3 ± 21.1 ms, p < 0.043) was significantly delayed in the affected ankle of the patients than in the controls. The dynamic balance test and time to peak torque in CAI patients remained significantly reduced at the time of return-to-sport after MBP. Clinicians and therapists should be aware of potential deficits in proprioception and neuromuscular control when determining the timing of return to sports after MBP.


Asunto(s)
Articulación del Tobillo/cirugía , Inestabilidad de la Articulación/cirugía , Procedimientos Ortopédicos/rehabilitación , Propiocepción , Volver al Deporte/fisiología , Adulto , Articulación del Tobillo/fisiopatología , Femenino , Humanos , Inestabilidad de la Articulación/fisiopatología , Masculino , Estudios Retrospectivos , Adulto Joven
20.
Artículo en Inglés | MEDLINE | ID: mdl-36612416

RESUMEN

Abnormal foot posture and poor muscle performance are potential causes of plantar fasciitis (PF). However, no study has compared the differences between lower extremity muscle performance and foot pressure in patients who have PF with and without abnormal foot postures. This study aimed to compare the differences in lower extremity muscle performance, such as in the hip, quadriceps, hamstring, and plantar flexor, and foot pressure in patients who have PF with and without flat foot postures. Seventy patients with plantar heel pain were enrolled (37 flat feet and 33 without flat feet). The hip muscle strength was measured using a handheld digital dynamometer. The strength and reaction time of the quadriceps, hamstring, and plantar flexor muscles were evaluated using an isokinetic device. Foot pressure parameters were assessed using pedobarography. The strength of the plantar flexor muscles was significantly lower (p = 0.008), while the reaction time of the plantar flexor muscles was significantly faster (p = 0.007) for the involved feet of PF patients with flat feet than in those without flat feet. This study confirmed the differences in muscle performance between patients who have PF with different foot postures. Therefore, clinicians and therapists should plan treatment considering the differences in these characteristics for the management of these patients.


Asunto(s)
Fascitis Plantar , Pie Plano , Humanos , Fascitis Plantar/terapia , Pie/fisiología , Músculo Esquelético/fisiología , Postura/fisiología
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