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1.
Adv Sci (Weinh) ; 11(14): e2308978, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38279580

RESUMO

Innate immune training involves myelopoiesis, dynamic gene modulation, and functional reprogramming of myeloid cells in response to secondary heterologous challenges. The present study evaluates whether systemic innate immune training can protect tissues from local injury. Systemic pretreatment of mice with ß-glucan, a trained immunity agonist, reduces the mortality rate of mice with bleomycin-induced lung injury and fibrosis, as well as decreasing collagen deposition in the lungs. ß-Glucan pretreatment induces neutrophil accumulation in the lungs and enhances efferocytosis. Training of mice with ß-glucan results in histone modification in both alveolar macrophages (AMs) and neighboring lung epithelial cells. Training also increases the production of RvD1 and soluble mediators by AMs and efferocytes. Efferocytosis increases trained immunity in AMs by stimulating RvD1 release, thus inducing SIRT1 expression in neighboring lung epithelial cells. Elevated epithelial SIRT1 expression is associated with decreased epithelial cell apoptosis after lung injury, attenuating tissue damage. Further, neutrophil depletion dampens the effects of ß-glucan on macrophage accumulation, epigenetic modification in lung macrophages, epithelial SIRT1 expression, and injury-mediated fibrosis in the lung. These findings provide mechanistic insights into innate immune training and clues to the potential ability of centrally trained immunity to protect peripheral organs against injury-mediated disorders.


Assuntos
Lesão Pulmonar , beta-Glucanas , Camundongos , Animais , Sirtuína 1 , Eferocitose , Lesão Pulmonar/prevenção & controle , beta-Glucanas/farmacologia , Fibrose
2.
Polymers (Basel) ; 15(21)2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37959968

RESUMO

In tire tread applications, achieving enhanced abrasion resistance, wet grip, and rolling resistance is crucial for optimizing overall performance. To realize improvements in these attributes for silica-filled tire tread compounds, it becomes imperative to improve the dispersity of silica filler by investigating the effect of each component in the tire tread compound. In this work, we study the effect of styrene content within solution styrene butadiene rubber (SSBR) on the properties of tire tread compounds. A higher styrene segment within SSBR contributes to increased silica dispersion and crosslink density. Thus, tire tread compounds featuring SSBR with increased styrene content not only improve physical and mechanical properties, but also enhance major characteristics tailored for tire tread applications. These findings provide valuable insights into advancing the reinforced performance of tire tread compounds through the strategic utilization of SSBR enriched in styrene content.

4.
Clin Orthop Surg ; 15(2): 203-210, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37008972

RESUMO

Background: Subchondral fatigue fracture of the femoral head (SFFFH) is a rare disease, and its disease entity is established in recent decades. Although there are a few studies on SFFFH, most of them are case series involving around 10 cases, and the clinical course of SFFFH is still not well known. This study analyzed the factors affecting the clinical course of SFFFH. Methods: Patients who visited our institution from October 2000 to January 2019 were retrospectively evaluated. Of eligible cases, 89 hips (80 patients) were diagnosed with SFFFH and non-surgical treatment outcomes were analyzed. Radiographs and medical charts were reviewed for following factors: the degree of femoral head collapse, the interval between the onset of hip pain and the first hospital visit, hip dysplasia, osteoarthritic changes, sex, and age. Results: Hip pain decreased in 82 cases (92.1%) through non-surgical treatment, and 7 cases (7.9%) underwent surgery. Patients with good results of non-surgical treatment had improvement 2.9 months on average after the treatment. All cases without a collapsed femoral head (55 cases) had hip pain alleviation through non-surgical treatment. Cases with femoral head collapse of 4 mm or less and non-surgical treatment within 6 months from the onset of hip pain (22 cases) all had hip pain alleviation. Among 8 cases with femoral head collapse of 4 mm or less and non-surgical treatment after 6 months or more from the onset of hip pain, 3 underwent surgery and 1 had persistent hip pain. Those with femoral head collapse of over 4 mm (3 cases) all underwent surgery. The osteoarthritic changes, dysplastic hip, sex, and age were not statistically related to the success of non-surgical treatment. Conclusions: The success of non-surgical treatment for SFFFH can be affected by the degree of femoral head collapse and the timing of non-surgical treatment.


Assuntos
Necrose da Cabeça do Fêmur , Fraturas de Estresse , Humanos , Cabeça do Fêmur/diagnóstico por imagem , Cabeça do Fêmur/cirurgia , Fraturas de Estresse/diagnóstico por imagem , Fraturas de Estresse/terapia , Estudos Retrospectivos , Resultado do Tratamento , Dor , Artralgia , Progressão da Doença
5.
Clin Orthop Surg ; 14(3): 328-334, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36061846

RESUMO

Background: Incomplete fractures are assumed to occur in the intertrochanteric area as fractures at other sites, but reports of incomplete intertrochanteric fractures (IIFs) are rare. In 1999, Schultz et al. defined isolated greater trochanter fractures (GTFs) as IIFs when intertrochanteric extension is observed on magnetic resonance (MR) images. On multiplanar reformation computed tomography (MPR CT) images acquired for further study of apparently isolated GTFs, we noted incomplete cortical breakage in the intertrochanteric area. We then found that the fracture line was incomplete on plain radiographs in some intertrochanteric fractures. We evaluated IIFs and apparently isolated GTFs using MPR CT and analyzed the fracture patterns of IIFs that were confirmed using MPR CT. Methods: Between February 2006 and June 2019, 36 cases of IIF were detected using MPR CT in 36 patients. They were 17 women and 19 men with a mean age of 74.7 years (range, 26-94 years). Plain radiographs and MPR CT images were evaluated by two experienced orthopedic surgeons. In addition, MR imaging was performed in 5 cases. Results: Plain radiographs showed no evidence of fracture in 2 cases, isolated GTF in 7 cases, and IIF in 27 cases. In all cases, incomplete cortical breakage in the intertrochanteric area was confirmed on MPR CT images. Cortical breakage was located in the anterior portion of the intertrochanteric area, whereas the posterior portion remained intact in all cases. The detection rate of cortical breakage was higher on coronal or sagittal images than that on axial images. On MR images of 5 cases, intertrochanteric extensions were found in the medullary space. All extensions originated in the greater trochanter area and extended anteriorly in the axial plane and inferomedially in the coronal plane. On the T1-weighted mid-coronal image, the extension reached or passed the midline in 3 cases, and cortical breakage was detected in only 2 cases. Conclusions: In all cases of IIF, cortical breakage was detected in the anterior portion of the proximal femur, leaving the posterior cortex intact. This finding is notably different from that of intertrochanteric extension (from posterior to anterior) detected on MR images of isolated GTFs.


Assuntos
Fraturas do Quadril , Idoso , Feminino , Fêmur , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Radiografia , Tomografia Computadorizada por Raios X/métodos
6.
Clin Orthop Surg ; 14(2): 184-190, 2022 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-35685972

RESUMO

Background: The current trend of using short femoral stems in total hip arthroplasty (THA) is associated with angular deviation of the femoral stem towards the native femoral axis. The purpose of this study was to compare the difference in stem tilt angle between two different stems with a similar design except for the stem length. Methods: This is a retrospective review of 66 patients who underwent primary THA between April 2012 and May 2016, using a trans-gluteal direct lateral approach by a single surgeon. We evaluated the femoral stem tilt angle in both the coronal and sagittal planes and performed multivariate logistic regression analysis to evaluate possible risk factors. We also simulated the range of motion (ROM) of the hip joint using three-dimensional computer-aided design software (SolidWorks, 2016) to examine the clinical significance of femoral stem tilt. Results: The mean coronal tilt angle was 1.8° ± 1.0° in the conventional stem group and 1.6° ± 1.1° in the short stem group, showing no statistically significant difference between the groups (p = 0.570). However, the mean sagittal tilt angle was 4.0° ± 2.0° in the conventional stem group and 7.8° ± 2.0° in the short stem group (p < 0.001). The stem type and stem length had a linear correlation with the sagittal tilt angle (p < 0.001) in multivariate regression analysis. A simulated hip ROM demonstrated a 3.8° decrease in extension in proportion to a 3.8° increase in the mean sagittal stem tilt angle of the short femoral stem. Conclusions: Anterior femoral stem tilting in the sagittal plane was prominent when the shorter stem was used, and anterior tilting was responsible for decreased ROM in hip extension.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Artroplastia de Quadril/métodos , Estudos de Casos e Controles , Fêmur/diagnóstico por imagem , Fêmur/cirurgia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Humanos , Amplitude de Movimento Articular , Estudos Retrospectivos
7.
Clin Orthop Surg ; 14(1): 21-27, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-35251537

RESUMO

BACKGROUND: Most isolated greater trochanter (IGT) fractures are treated conservatively. However, some require surgical fixation although indications for surgery have not yet been established. Many surgeons perform surgical fixation when the intertrochanteric extension crosses the midline on magnetic resonance (MR) images. Nevertheless, for mechanical strength, cortical bone integrity is more important than that of intramedullary cancellous trabeculae. We retrospectively evaluated the clinical usefulness of multiplanar reformation computed tomography (MPR CT) in determining treatment strategies for IGT fractures. METHODS: We evaluated 99 cases of suspected IGT fractures between October 2004 and December 2019. They were 66 women and 33 men with a mean age of 77 years. The mean follow-up period was 34 months. Most patients were evaluated with plain radiographs, followed by additional imaging study via MPR CT in 65 cases, magnetic resonance imaging (MRI) in 5 cases, and both in 17 cases. Typically, fractures were fixed surgically when a cortical breakage was detected in the intertrochanteric area on MPR CT, while fractures without evidence of cortical breakage on MPR CT were treated conservatively. RESULTS: In 13 out of 82 cases evaluated by MPR CT, incomplete cortical breakage in the intertrochanteric area was detected, of which 10 were treated surgically. The remaining 3 cases were treated conservatively due to patient's refusal, poor medical condition, and failure to detect breakage. Of 69 cases without cortical breakage, 61 cases were successfully treated conservatively. Among the 17 cases evaluated by both MPR CT and MRI, cortical breakage was detected in 3, of which the intertrochanteric extension crossed the midline on the MR image only in 1 case. Of the remaining 14 cases without breakage, the intertrochanteric extension crossed the midline in 5. Among these 5 cases, 3 were treated conservatively. CONCLUSIONS: The results suggest that MPR CT is a useful imaging modality for further evaluation of IGT fractures. It was especially valuable in evaluating cortical bone integrity, which may be more critical for fracture stability.


Assuntos
Fraturas do Quadril , Idoso , Feminino , Fêmur , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/cirurgia , Humanos , Imageamento por Ressonância Magnética , Masculino , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos
8.
Clin Orthop Surg ; 13(1): 37-46, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33747376

RESUMO

BACKGROUD: Outcomes of traditional treatment for osteonecrosis of the femoral head (ONFH) are not always satisfactory. Hence, cell-supplementation therapy has been attempted to facilitate necrotic-tissue regeneration. Adipose-derived mesenchymal stem cell (ADMSC) transplantation is potentially advantageous over bone marrow-derived MSC implantation, but its outcomes for ONFH remain unclear. The aim of this study was to determine 2-year radiological and clinical outcomes of culture-expanded autologous ADMSC implantation for ONFH. METHODS: Eighteen hips with necrotic lesions involving ≥ 30% of the femoral head were included. ADMSCs were harvested by liposuction and culture expanded for 3 passages over 3 weeks. With a 6-mm single drilling, ADMSCs were implanted into the necrotic zone. All patients underwent magnetic resonance imaging (MRI), single-photon emission computed tomography/computed tomography (SPECT/CT) at screening and 6 months, 12 months, and 24 months postoperatively. The primary outcome was the change in the size of necrotic area on MRI. Secondary outcomes were changes in clinical scores and radioisotope uptake on SPECT/CT. Conversion total hip arthroplasty (THA) was defined as the endpoint. RESULTS: Preoperatively, the necrotic lesion extent was 63.0% (38.4%-96.7%) of the femoral head. The mean Harris hip score was 89.2, the University of California at Los Angeles (UCLA) score was 5.6, and Western Ontario and McMaster Universities Arthritis index (WOMAC) was 79.4. Three patients underwent THA and 1 patient died in an accident. Finally, 11 patients (14 hips) were available for ≥ 2-year follow-up. At the last follow-up, no surgery-related complications occurred, and 14 of 17 hips (82%) were able to perform daily activities without THA requirement. There was no significant decrease in lesion size between any 2 intervals on MRI. However, widening of high signal intensity bands on T2-weighted images inside the necrotic lesion was observed in 9 of 14 hips (64%); 11 of 14 hips (79%) showed increased vascularity on SPECT/CT at 2 years postoperatively. No significant differences were observed between preoperative and 24-month mean Harris hip score (89.2 vs. 88.6), WOMAC (79.4 vs. 75.7), and UCLA score (5.6 vs. 6.2). CONCLUSIONS: Our outcomes suggest that culture-expanded ADMSC implantation is a viable option for ONFH treatment without adverse events.


Assuntos
Descompressão Cirúrgica/métodos , Necrose da Cabeça do Fêmur/terapia , Transplante de Células-Tronco Mesenquimais/métodos , Tecido Adiposo/citologia , Adulto , Avaliação da Deficiência , Feminino , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Transplante Autólogo , Adulto Jovem
9.
J Phys Chem B ; 125(1): 450-460, 2021 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-33400517

RESUMO

Poly(ethylene terephthalate) (PET) is one of the most prevalent polymers in the world due to its combined thermal, mechanical, and gas barrier attributes. Blending PET with other polymers is an appealing strategy to further tailor properties to meet the needs of an even more diverse range of applications. Most blends with PET are macrophase-separated; only a few miscible systems have been reported. Here, the miscibility of the aromatic polyesters poly(salicylic glycolide) (PSG) and poly(salicylic methyl glycolide) (PSMG) with PET is described. Both PSG and PSMG have similar chemical structures to PET but are derived from sustainable resources and readily degradable. This study suggests that they are fully miscible with PET over the entire composition range, which is attributed to favorable interactions with PET. Negative polymer-polymer interaction parameters (χ) were determined using Flory-Huggins theory to describe melting temperature variations in the blends. In addition, the PET blends showed mechanical properties that are intermediate between the two homopolymers.

10.
J Bone Joint Surg Am ; 103(2): 139-145, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-33269897

RESUMO

BACKGROUND: It is assumed that impingement between the ceramic liner and the stem increases the possibility of a liner fracture in total hip arthroplasty with a ceramic-on-ceramic bearing. The purpose of this study was to analyze the pattern of the impingement by evaluating the notches (U-shaped indented wear scars engraved on the stem) on radiographs to determine when and where impingement develops and to analyze the factors affecting its occurrence. METHODS: Among the primary total hip arthroplasty cases using a ceramic-on-ceramic bearing performed from November 1997 to December 2003, 244 cases of 197 patients (123 male patients and 74 female patients) that had follow-up of ≥15 years were included. All of the radiographs were examined with special regard to the notches and the cup positions. RESULTS: Notches were detected at 77 sites of 57 cases (23.4%) for the first time between 8 months and 14.8 years after the surgical procedure. They were located on the neck or the shoulder of the stem. Shoulder notches were detected only in the cases with a short-neck head. Shoulder notches were found in 29 cases (20.0% of short-neck cases). Cup inclination was lower (p = 0.01) and anteversion was higher (p = 0.01) in the group with notches than the group without notches. There were 5 cases of ceramic head fracture. One of them experienced another ceramic liner fracture, assumed to be caused by prosthetic shoulder impingement, after the revision surgical procedure. CONCLUSIONS: The results of this study suggest that impingement between the stem and the ceramic liner occurs in a considerable proportion of patients who underwent total hip arthroplasty not only on the neck but also on the shoulder of the stem. Forceful and abrupt impingement on the stem shoulder can cause ceramic liner fracture. Impingement between the stem shoulder and the ceramic liner should be considered in designing a stem. It seems to be prudent to recommend that patients avoid squatting or sitting cross-legged on the floor as much as possible. LEVEL OF EVIDENCE: Therapeutic Level IV. See Instructions for Authors for a complete description of levels of evidence.


Assuntos
Artroplastia de Quadril/efeitos adversos , Impacto Femoroacetabular/diagnóstico por imagem , Articulação do Quadril/cirurgia , Prótese de Quadril/efeitos adversos , Falha de Prótese/efeitos adversos , Adolescente , Adulto , Idoso , Materiais Biocompatíveis , Cerâmica , Feminino , Impacto Femoroacetabular/etiologia , Articulação do Quadril/diagnóstico por imagem , Humanos , Artropatias/diagnóstico por imagem , Artropatias/cirurgia , Masculino , Metais , Pessoa de Meia-Idade , Desenho de Prótese/efeitos adversos , Fatores de Risco , Adulto Jovem
11.
Clin Orthop Surg ; 12(4): 435-441, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33274019

RESUMO

BACKGROUND: Hereditary multiple exostoses (HME) is an autosomal dominant disorder. The lesion in the proximal femoral metaphysis can bring about hip dysplasia and subsequent degenerative arthritis. Due to its rare prevalence, there have been a few case reports of total hip arthroplasty (THA) for osteoarthritis secondary to HME. The aim of this study was to report mid- to long-term outcomes of THA in HME patients and discuss special considerations that should be taken into account during surgery. METHODS: We retrospectively evaluated the clinical and radiological results of THA for osteoarthritis secondary to HME in 11 hips of 9 patients after a minimum follow-up of 5 years (mean, 9.9 years). There were 3 men (3 hips) and 6 women (8 hips), with a mean age of 53.6 years (range, 46.8-58 years) at the index surgery in this study. Harris hip score (HHS) was used for clinical outcome assessment, and radiologically, implant stability, radiolucent lines, liner wear, and any sign of osteolysis or implant loosening were evaluated. Postoperative complications including infection, deep vein thrombosis, and dislocations were also investigated. RESULTS: Cemented stems and cementless cups with the conventional polyethylene liner were used in bilateral hips of a single patient. In the other cases, cementless implants were used with ceramic-on-ceramic bearings. The mean HHS improved from 34.8 preoperatively to 92.5 postoperatively. Polyethylene liner wear and osteolysis were observed in 1 patient with cemented stems. Radiolucent lines were observed in 2 different cases. However, the femoral stems remained stable. There were no surgery-related complications except heterotopic ossification during follow-up. CONCLUSIONS: Despite the several surgical considerations, the mid- to long-term clinical and radiological outcomes of THA in HME patients were satisfactory. The abnormal, wide mediolateral diameter of the proximal metaphysis should be considered in selecting and inserting the stem with adequate anteversion. Leg length discrepancy was also common, so teleradiographs should be obtained before surgery. Intraoperative leg length evaluation might be difficult due to the morphologic changes in the proximal femur after mass excision and individual bone length differences.


Assuntos
Artroplastia de Quadril/métodos , Exostose Múltipla Hereditária/cirurgia , Osteoartrite do Quadril/cirurgia , Idoso , Exostose Múltipla Hereditária/complicações , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/etiologia , Estudos Retrospectivos , Inquéritos e Questionários
12.
PLoS One ; 15(10): e0240993, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33091048

RESUMO

BACKGROUND: Acetabular labral tears cause of pain in patients with symptomatic hip dysplasia. To date, no structured grading system has been developed to evaluate labral tears in these patients. The present study describes a new system of grading labral tears in patients with acetabular dysplasia. METHODS: The data of 66 patients who underwent hip arthroscopy for symptomatic hip dysplasia from March 2014 to February 2018 were reviewed. Labral tears were classified into four groups, based on the occurrence of chondrolabral junction (CLJ) disruption, capsulolabral recess (CLR) disruption, and labral displacement. Labral tears without instability were classified as grade 1 or 2. Partial delamination or blistering of the labrum with minimal fraying at the CLJ was classified as grade 1, whereas labral tears with CLJ disruption were classified as grade 2. Unstable labral tears with CLR disruption followed by CLJ disruption, but without labral displacement, were classified as grade 3, whereas unstable labral tears with CLR and CLJ disruption, but with labral displacement, were classified as grade 4. The radiological and clinical characteristics of patients in each grade were determined including by simple radiographs and MRI/MR arthrography, as were concomitant findings, including rupture of the ligamentum teres, articular cartilage damage, and presence of a paralabral cyst. The surgical options selected for each grade and clinical outcomes, including modified Harris hip scores (mHHS) and Western Ontario and McMaster Universities Osteoarthritis index (WOMAC) scores, were evaluated. Spearman's correlation analyses were performed to assess whether labral tear grade correlated with baseline characteristics, the incidence of concomitant injuries, and the severity of osteoarthritis (OA). The Wilcoxon test for paired data was performed to compare treatment results with pain scores. RESULTS: The study cohort included six men and 53 women of mean ± SD age 39.9 ± 13.0 years (range, 15-66 years). Of the 66 hips, seven (10.6%), 10 (15.2%), 30 (45.5%), and 19 (28.8%) were classified as grades 1-4, respectively. Symptom duration (P = 0.017), preoperative Tönnis OA grade (P < 0.001), cartilage damage (P < 0.001), and the presence of a paralabral cyst (P = 0.001) correlated significantly with baseline tear grade. In all groups, mHHS and WOMAC scores improved after surgical treatment. CONCLUSIONS: Arthroscopic findings of labral tears in patients with hip dysplasia differed from the conventional classification. The classification system proposed in this study will likely be useful for determining the degree of labral tear in patients with hip dysplasia and for predicting treatment outcomes.


Assuntos
Luxação do Quadril/diagnóstico por imagem , Luxação do Quadril/diagnóstico , Acetábulo/efeitos dos fármacos , Adolescente , Adulto , Idoso , Artrografia/métodos , Artroscopia/métodos , Cartilagem Articular/diagnóstico por imagem , Estudos de Coortes , Feminino , Articulação do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite/diagnóstico , Ruptura/diagnóstico , Resultado do Tratamento , Adulto Jovem
13.
Clin Orthop Surg ; 12(3): 298-303, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32904015

RESUMO

BACKGROUD: Herniation pits (HPs) have been considered to be an incidental finding, but recently femoroacetabular impingement (FAI) has been proposed as a possible cause of their formation. The findings on bone scans of HPs are variable in the literature: some showed increased uptake; the majority did not. We hypothesized that serial changes in image findings of HPs would explain the reason for the variable bone scan findings. METHODS: Four patients (5 hips) were followed up for more than 7 years. All patients were women and regularly underwent bone scintigraphy after the diagnosis of breast cancer. Small lesions with increased uptake were first detected on bone scintigraphy at the age of 44 to 64 years. In all cases, the lesions were confirmed by magnetic resonance imaging and follow-up bone scintigrams were taken regularly. Four lesions were also evaluated by computed tomography. Changes in the size of the pits and the intensity of the increased uptake on bone scintigraphy were evaluated. RESULTS: On the bone scintigrams, the lesions with increased uptake were detected in the femoral neck at 5-20 months after previous negative bone scintigraphy. There had been no events or symptoms associated with the newly detected increased uptake. On follow-up scans, the intensity of the uptake decreased gradually and the areas of increased uptake disappeared completely at 14-50 months after their first appearance. In 3 cases (2 patients), the pit size increased during follow-up. CONCLUSIONS: The areas of increased uptake on bone scintigraphy gradually disappeared in all cases and the increase in pit size was frequent. There was no case in which signs or symptoms suggestive of FAI were noticed.


Assuntos
Impacto Femoroacetabular/diagnóstico por imagem , Impacto Femoroacetabular/patologia , Adulto , Progressão da Doença , Feminino , Colo do Fêmur/diagnóstico por imagem , Colo do Fêmur/patologia , Humanos , Pessoa de Meia-Idade , Fatores de Tempo
14.
Environ Res ; 188: 109746, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32540570

RESUMO

This study investigated effects of the thermal hydrolysis pre-treatment on mechanical deep dewaterability of dewatered sludge to extend understanding of dewatering characteristics of thermally hydrolyzed sludge. Floc sizes of dewatered sludge were gradually reduced during the thermal hydrolysis pre-treatment at 170 °C and 185 °C with increasing retention time whereas longer retention time (>60 min) increased floc sizes of thermally hydrolyzed sludges at 200 °C due to formation of undesired refractory organic materials (ROMs), which might hinder the disintegration of dewatered sludge flocs. Similar trends were found for thermal hydrolytic solubilization of dewatered sludge. This demonstrated that the efficiency of the thermal hydrolysis pre-treatment at a higher temperature (200 °C) with longer retention time (≥60 min) could be strongly influenced by the formation of ROMs associated with changes of solid fractions and some free amino acids (i.e., ß-aminobutyric acid, 4-hydroxyproline, and cysteine). Since the trade-off between the degradation of dewatered sludge and the formation of ROMs determined mechanical deep dewaterability of thermally hydrolyzed sludge, the lowest residual weight and moisture content were observed for thermally hydrolyzed sludges at 200 °C with retention time range of 60 min (residual weight = 0.165; moisture content = 55.38%) to 90 min (residual weight = 0.160; moisture content = 59.87%). These observations were intimately correlated to variations of extracellular polymeric substances during the thermal hydrolysis pre-treatment, but not in accordance with the change pattern of capillary suction time (CST) values. This is evident that the CST value was inadequate to estimate mechanical deep dewaterability of thermally hydrolyzed sludge.


Assuntos
Esgotos , Eliminação de Resíduos Líquidos , Temperatura Alta , Hidrólise , Temperatura , Água
15.
ACS Appl Mater Interfaces ; 12(8): 9726-9735, 2020 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-32017525

RESUMO

Plastic pollution is one of the most pressing global environmental issues we face today, in part due to the continued rise in production and use of disposable plastic products. Polyolefins and polyesters are two of the most prevalent polymers in the world accounting for ∼80% of total nonfiber plastic production. Recycling, despite being intrinsically environmentally friendly and sometimes economically viable, remains at a surprisingly low level (<9% in the U.S.) with most plastic waste ending up in landfills. One reason for this low rate of recycling stems from the challenge of recycling mixed waste streams and multicomponent plastics. In mixed waste streams, physical presorting of components prior to recycling requires significant effort, which translates to added cost. For multicomponent plastics (e.g., multilayer films such as food wrappers), the individual plastic components cannot be efficiently physically separated, and they are immiscible with poor interfacial adhesion when melt reprocessed. Thus, direct recycling of mixed plastics by melt reprocessing results in products that lack desired end-use properties. In this study, we describe the synthesis of novel poly(ethylene terephthalate)-polyethylene multiblock copolymers (PET-PE MBCPs) and evaluate their utility as adhesive tie layers in multilayer films and compatibilizer additives for melt reprocessed blends. PET and PE are targeted because they are two of the most prevalent commercial polymers in the world and are high volume waste streams. The work described here demonstrates two key findings. First, the PET-PE MBCPs serve as effective adhesive tie layers between neat PET/PE films with adhesive strength comparable to that of commercially available adhesives. Second, PET/PE (80/20 wt %) blends containing ∼0.5 wt % PET-PE MBCP were melt mixed to mimic recycling mixed plastic waste, and they were found to exhibit mechanical properties better than neat PET. Overall, this study demonstrates that PET-PE MBCPs could significantly enhance the ability to recycle PET/PE mixed waste streams by serving the role as both an adhesive promoting layer and a compatibilizer additive.

16.
Clin Orthop Surg ; 11(3): 361-368, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31475059

RESUMO

BACKGROUND: Adequate bone formation around titanium alloy implants is integral to successful implantation surgery. Stem cell-coated implants may accelerate peri-implant bone formation. This study investigates the effect of platelet-rich plasma (PRP) pretreatment on a titanium-alloy surface in terms of proliferation and osteogenic differentiation of human adipose-derived stem cells (hADSCs). METHODS: Allogenic leukocyte-depleted PRP was obtained from blood supernatants. The hADSCs were isolated from thigh subcutaneous fat tissue. Grit-blasted titanium plugs were used in two different groups. In one group, 200 µL of PRP was added to the grit-blasted titanium plugs. The hADSCs were seeded in two groups: grit-blasted titanium plugs with or without PRP. The number of hADSCs was measured after 4 hours, 3 days, and 7 days of culture using Cell Counting Kit-8. Osteogenesis of hADSCs was measured by using an alkaline phosphatase activity assay on days 7 and 14, and a calcium assay on days 14 and 21. Osteogenic gene expression was measured by using reverse transcription polymerase chain reaction analysis of alkaline phosphatase, osteocalcin, and type I collagen mRNA. The microscopic morphology of grit-blasted titanium plugs with or without PRP was examined with a field-emission scanning electron microscope using a JSM-7401F apparatus on days 1 and 7. RESULTS: Proliferation and osteogenic differentiation of hADSCs were found to be significantly higher on the grit-blasted titanium alloy preprocessed with PRP than the same alloy without pretreatment. Furthermore, a structural fibrillar mesh developed compactly on the grit-blasted titanium alloy with the PRP pretreatment. CONCLUSIONS: Our results demonstrate that a hADSC-based approach can be used for tissue-engineered peri-implant bone formation and that PRP pretreatment on the grit-blasted titanium alloy can improve proliferation and osteogenic differentiation of hADSCs.


Assuntos
Células-Tronco Mesenquimais/fisiologia , Osseointegração/fisiologia , Osteogênese/fisiologia , Plasma Rico em Plaquetas , Próteses e Implantes , Ligas , Materiais Biocompatíveis , Diferenciação Celular , Proliferação de Células , Humanos , Engenharia Tecidual , Titânio
17.
Clin Orthop Surg ; 11(3): 270-274, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31475046

RESUMO

BACKGROUND: The isolated liner and head exchange procedure has been an established treatment method for polyethylene wear and osteolysis when the acetabular component remains well fixed. In this study, the mid-term results of this procedure were evaluated retrospectively. METHODS: Among the consecutive patients operated on from September 1995, two patients (three hips) were excluded because of inadequate follow-up, and the results of remaining 34 patients (34 hips) were evaluated. There were 20 men and 14 women with a mean age of 49 years. A conventional polyethylene liner was used in 26 cases and a highly cross-linked polyethylene liner was used in eight cases. In three cases, the liner was cemented in a metal shell because a compatible liner could not be used. RESULTS: After a follow-up of 5 to 20.2 years, re-revision surgery was necessary in 10 cases (29.4%): in eight for wear and osteolysis at 55 to 101 months after liner exchange and in two for acetabular loosening at 1 and 1.5 years after liner exchange. Re-revision surgery included all component revision (four cases), cup revision (four cases), and liner exchange (two cases). In all re-revision cases, a conventional polyethylene liner was used initially. There was no failure in the cases in which a highly cross-linked polyethylene liner was used. CONCLUSIONS: The results of this study suggest that isolated acetabular liner exchange is a reasonable option for wear and osteolysis when the metal shell is well fixed. More promising long-term results are expected with the use of highly cross-linked polyethylene liners.


Assuntos
Acetábulo/cirurgia , Artroplastia de Quadril/métodos , Prótese de Quadril/efeitos adversos , Osteólise/cirurgia , Falha de Prótese , Adulto , Idoso , Idoso de 80 Anos ou mais , Materiais Biocompatíveis , Feminino , Humanos , Masculino , Metais , Pessoa de Meia-Idade , Osteólise/etiologia , Polietileno , Desenho de Prótese , Falha de Prótese/etiologia , Reoperação , Estudos Retrospectivos , Adulto Jovem
18.
Hip Pelvis ; 30(3): 162-167, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30202750

RESUMO

PURPOSE: This study presents the clinical and radiological outcomes of cementless total hip arthroplasty using the COREN hip system after a minimum duration of follow-up of 5 years. MATERIALS AND METHODS: We evaluated the results of a consecutive series of the first 200 primary total hip arthroplasties that had been performed in our hospital in 169 patients between February 2007 and April 2011. Six patients (6 hips) had died within 5 years, and 12 patients (13 hips) had been lost to follow-up, leaving a total of 151 patients (181 hips) available for the study. All patients were evaluated clinically and radiologically with special attention to thigh pain, implant fixation, radiolucent line and osteolysis around implants. RESULTS: The mean Harris hip score improved from 59.4 preoperatively to 97.2 postoperatively. No patient complained of thigh pain. All implants demonstrated radiographic evidence of stable fixation by bone ingrowth without any change in position. No implant was loose radiographically or was revised. Eleven hips (7.7%) had a radiolucent line around the femoral stem. Focal osteolytic area was detected in 3 cases (2.1%). An osteolytic lesion was stabilized in 1 case and further observation was needed in 2 cases in which the lesions were detected several years after surgery. Stress shielding was observed in 80.3% of cases (first degree, 35.9%; second degree, 44.4%); there were no cases of third or fourth degree stress shielding. One case was complicated by bacterial infection and repeated dislocation. CONCLUSION: Mid-term results of total hip arthroplasty using the COREN hip system are very encouraging clinically and radiologically.

19.
Clin Orthop Surg ; 10(1): 20-25, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29564043

RESUMO

BACKGROUND: This retrospective study was performed to determine whether postoperative intravenous ferric carboxymaltose reduces transfusion amounts without influencing clinical outcomes in patients that have undergone hip surgery. METHODS: Between May 2014 and April 2016, the authors adopted a new perioperative blood management protocol involving the administration of intravenous ferric carboxymaltose after hip surgeries. One-to-one matching between the 150 patients treated during this period with 150 patients treated before initiation of the new protocol was performed by propensity scoring for age, sex, diagnosis, and type of hip surgery. Hematologic results and clinical outcomes in these two groups were compared. RESULTS: Average amounts of perioperative blood loss were not different in the two groups. Ninety-two patients (61%) were transfused in the control group and 70 patients (47%) were transfused in the intravenous ferric carboxymaltose group. The average number of transfused blood units was significantly lower in the intravenous ferric carboxymaltose group (1.7 ± 2.7 units vs. 1.0 ± 1.2 units, p = 0.002). At 6 weeks after surgery, the average hemoglobin concentration recovered to baseline in both groups, but the amount of recovered hemoglobin concentration at 6 weeks was significantly greater in the intravenous ferric carboxymaltose group than in the control group. Clinical outcomes including incidences of postsurgical complications were similar between the two groups. CONCLUSIONS: This study suggests that postoperative intravenous ferric carboxymaltose injection is associated with reduced transfusion amounts and that intravenous ferric carboxymaltose does not influence clinical outcomes after hip surgery.


Assuntos
Transfusão de Sangue , Compostos Férricos/administração & dosagem , Hemoglobinas/metabolismo , Articulação do Quadril/cirurgia , Maltose/análogos & derivados , Administração Intravenosa , Adulto , Idoso , Idoso de 80 Anos ou mais , Perda Sanguínea Cirúrgica , Feminino , Humanos , Tempo de Internação , Masculino , Maltose/administração & dosagem , Pessoa de Meia-Idade , Cuidados Pós-Operatórios , Complicações Pós-Operatórias/etiologia , Pontuação de Propensão , Estudos Retrospectivos , Adulto Jovem
20.
ACS Appl Mater Interfaces ; 10(4): 3479-3486, 2018 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-29298374

RESUMO

Na-ion batteries are attractive as an alternative to Li-ion batteries because of their lower cost. Organic compounds have been considered as promising electrode materials due to their environmental friendliness and molecular diversity. Herein, aluminum-coordinated poly(tetrahydroxybenzoquinone) (P(THBQ-Al)), one of the coordination polymers, is introduced for the first time as a promising cathode for Na-ion batteries. P(THBQ-Al) is synthesized through a facile coordination reaction between benzoquinonedihydroxydiolate (C6O6H22-) and Al3+ as ligands and complex metal ions, respectively. Tetrahydroxybenzoquinone is environmentally sustainable, because it can be obtained from natural resources such as orange peels. Benzoquinonedihydroxydiolate also contributes to delivering high reversible capacity, because each benzoquinonedihydroxydiolate unit is capable of two electron reactions through the sodiation of its conjugated carbonyl groups. Electrochemically inactive Al3+ improves the structural stability of P(THBQ-Al) during cycling because of a lack of a change in its oxidation state. Moreover, P(THBQ-Al) is thermally stable and insoluble in nonaqueous electrolytes. These result in excellent electrochemical performance including a high reversible capacity of 113 mA h g-1 and stable cycle performance with negligible capacity fading over 100 cycles. Moreover, the reaction mechanism of P(THBQ-Al) is clarified through ex situ XPS and IR analyses, in which the reversible sodiation of C═O into C-O-Na is observed.

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