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1.
Clin Orthop Relat Res ; 475(8): 2074-2080, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28512691

RESUMO

BACKGROUND: Complete circumferential osseous extension in the acetabular rim has been reported to occur in the deep hip with pincer impingement. However, this phenomenon occasionally is observed in dysplastic hips without pincer impingement, and the degree to which this finding might or might not be associated with hip pain, and how often it occurs bilaterally among patients, are not well characterized. QUESTIONS/PURPOSES: (1) To determine the proportion of patients with complete circumferential osseous extension in the acetabular rim using three-dimensional (3-D) CT in patients with and without hip pain who had CT scans obtained for various reasons. (2) To elucidate how often this complete circumferential osseous extension occurred bilaterally among those patients. (3) To investigate the relationship between the proportions of patients with complete circumferential osseous extension observed on CT scans among three different acetabular coverage groups: dysplasia, normal, and overcoverage. (4) To determine how often the finding of hip pain was associated with complete circumferential osseous extension. PATIENTS AND METHODS: Between September 2011 to July 2016, we evaluated 3788 patients with pelvic complaints such as hip, groin, thigh, buttock, or sacroiliac joint pain. We obtained consent from 26% (992 of 3788) of them, and obtained 3-D CT scans as part of that evaluation. For the current retrospective study, we excluded patients younger than 20 years or 80 years or older (181 patients), patients who had previous hip surgery (185 patients), patients with severe osteoarthritis with Tönnis Grades 2 or 3 (301 patients), and patients who could not have an accurate lateral center-edge (LCE) angle measured owing to poor-quality radiographs (24 patients), leaving 301 patients (602 hips) for this analysis. In this study population, patients reported pain in 131 hips (22%), defined as all types of hip pain except for trauma, including activity pain, pain with sports, pain on motion, and impingement pain; the others did not report hip pain. The mean age of the patients was 56 ± 16 years, and the mean LCE angle was 26° ± 8° (range, -9° to 47°). We first determined the proportion of patients with complete circumferential osseous extension in the acetabular rim using 3-D CT for those with and without hip pain who had CT obtained for various reasons. We next elucidated how often this complete circumferential osseous extension occurred bilaterally among the patients, and finally we investigated the relationship between the proportion of patients with complete circumferential osseous extension observed on CT scans among the three groups: dysplasia (defined as LCE angles of 22° or smaller), normal, and overcoverage (defined as LCE angles of 34° or larger) groups. We finally determined how often the finding was associated with hip pain attributable to complete circumferential osseous extension. RESULTS: The proportion of patients with complete circumferential osseous extension was 6% (18 of 301 patients). Eighty-nine percent (16 of 18) of the patients had bilateral complete circumferential osseous extension. There were no differences in the proportions of patients with complete circumferential osseous extension among the three groups: 5.3% (odds ratio [OR], 1.02; 95% CI, 0.45-2.31; p = 0.97), 5.3%, and 7.4% (OR, 0.70; 95% CI, 0.28-1.73; p = 0.44) in the dysplasia, normal, and overcoverage groups, respectively, with the numbers available. Eighteen percent (six of 34) of the hips with complete circumferential osseous extension had pain. CONCLUSIONS: Complete circumferential osseous extension in the acetabular rim is relatively uncommon. When it occurs, it usually is bilateral, it occurs regardless of acetabular coverage, and it is associated with pain in a minority of patients. LEVEL OF EVIDENCE: Level III, prognostic study.


Assuntos
Acetábulo/patologia , Artralgia/patologia , Luxação do Quadril/patologia , Articulação do Quadril/patologia , Acetábulo/diagnóstico por imagem , Adulto , Idoso , Artralgia/diagnóstico por imagem , Artralgia/etiologia , Feminino , Luxação do Quadril/complicações , Luxação do Quadril/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Humanos , Imageamento Tridimensional/métodos , Masculino , Pessoa de Meia-Idade , Razão de Chances , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Adulto Jovem
2.
BMC Musculoskelet Disord ; 16: 330, 2015 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-26527292

RESUMO

BACKGROUND: Although little is known, a limited number of three-dimensional computed tomography (CT) images of the pelvis present focal concavity of posterior superior acetabulum. The purpose of the present study was to investigate this morphologic deformity and its relation with dysplasia and retroversion in adults who were expected to have the original morphology of the acetabulum after growth. METHODS: Consecutive adult patients with hip pain who visited our hospital and had three-dimensional pelvic CT images were retrospectively analyzed after approval of the institutional review board; exclusion criterions included diseases, injuries and operations that affect the morphology of the hip including radiographic osteoarthritis Tönnis grades 2 and 3. Focal concavity of posterior superior acetabulum was evaluated by three-dimensional CT image. Acetabular dysplasia was determined by lateral center edge (LCE) angle <25°, Tönnis angle >10°, and anterior center edge (ACE) angle <25° on standing hip radiographs. Acetabular version angle was measured at the one-fourth cranial level of axial CT image. A subgroup analysis included only younger adult patients up to 50 years. RESULTS: The subjects analyzed were 46 men (92 hips) and 54 women (108 hips) with a median age of 57.5 (21-79) and 51.0 (26-77) years, respectively. Focal concavity of posterior superior acetabulum was observed in 13 hips; 7 patients had unilaterally, while 3 patients showed bilaterally. Among these hips, pain was observed in 8 hips but 4 hips (2 patients) were associated with injuries. This morphologic abnormality was not associated with acetabular dysplasia determined by LCE angle <25°, Tönnis angle >10° or ACE angle <25°. Of note, no acetabulum with the deformity plus dysplasia was retroverted. These findings were confirmed in a subgroup analysis including 22 men (44 hips) and 27 women (54 hips) with a median age of 31.0 (21-50) and 41.0 (26-50) years, respectively. CONCLUSIONS: Focal concavity of posterior superior acetabulum could be a rare morphologic abnormality of acetabular formation independent of lateral or anterior dysplasia or retroversion.


Assuntos
Acetábulo/anormalidades , Retroversão Óssea , Acetábulo/diagnóstico por imagem , Adulto , Idoso , Feminino , Luxação do Quadril/etiologia , Humanos , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Radiografia , Estudos Retrospectivos , Adulto Jovem
3.
Mod Rheumatol ; 25(2): 286-91, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25109744

RESUMO

OBJECTIVES: This study aimed to evaluate the clinical safety and wear-resistance of the novel highly cross-linked polyethylene (HXLPE) acetabular liner with surface grafting of poly(2-methacryloyloxyethyl phosphorylcholine) (PMPC) at 3 years after total hip replacement (THR). METHODS: Eighty consecutive patients underwent cementless THR using a 26-mm diameter cobalt-chromium-molybdenum alloy femoral head and a PMPC-grafted HXLPE liner for the bearing couplings. We evaluated the clinical and radiographic outcomes of 76 patients at 3 years after the index surgery. RESULTS: The clinical results at 3 years were equivalent to a Harris hip score of 95.6 points. No adverse events were associated with the implanted PMPC-grafted HXLPE liner, and no periprosthetic osteolysis was detected. The mean femoral head penetration rate was 0.002 mm/year, representing marked reduction compared with other HXLPE liners. CONCLUSIONS: A PMPC-grafted HXLPE liner is a safe option in THR and probably reduces the generation of wear particles.


Assuntos
Artroplastia de Quadril , Necrose da Cabeça do Fêmur/cirurgia , Articulação do Quadril/cirurgia , Prótese de Quadril , Osteoartrite do Quadril/cirurgia , Fosforilcolina/análogos & derivados , Ácidos Polimetacrílicos , Adulto , Idoso , Feminino , Necrose da Cabeça do Fêmur/diagnóstico por imagem , Articulação do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Osteoartrite do Quadril/diagnóstico por imagem , Estudos Prospectivos , Radiografia , Resultado do Tratamento
4.
Biochem Biophys Res Commun ; 444(4): 682-6, 2014 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-24513290

RESUMO

Accumulating evidence indicates that epigenetic aberrations have a role in the pathogenesis of rheumatoid arthritis (RA). However, reports on histone modifications are as yet quite limited in RA. Interleukin (IL)-6 is an inflammatory cytokine which is known to be involved in the pathogenesis of RA. Here we report the role of histone modifications in elevated IL-6 production in RA synovial fibroblasts (SFs). The level of histone H3 acetylation (H3ac) in the IL-6 promoter was significantly higher in RASFs than osteoarthritis (OA) SFs. This suggests that chromatin structure is in an open or loose state in the IL-6 promoter in RASFs. Furthermore, curcumin, a histone acetyltransferase (HAT) inhibitor, significantly reduced the level of H3ac in the IL-6 promoter, as well as IL-6 mRNA expression and IL-6 protein secretion by RASFs. Taken together, it is suggested that hyperacetylation of histone H3 in the IL-6 promoter induces the increase in IL-6 production by RASFs and thereby participates in the pathogenesis of RA.


Assuntos
Artrite Reumatoide/genética , Artrite Reumatoide/patologia , Fibroblastos/patologia , Histonas/metabolismo , Interleucina-6/genética , Regiões Promotoras Genéticas , Acetilação/efeitos dos fármacos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/metabolismo , Células Cultivadas , Curcumina/uso terapêutico , Inibidores Enzimáticos/uso terapêutico , Epigênese Genética , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Histona Acetiltransferases/antagonistas & inibidores , Histona Acetiltransferases/metabolismo , Histonas/genética , Humanos , Interleucina-6/análise , Osteoartrite/genética , Osteoartrite/metabolismo , Osteoartrite/patologia , Regiões Promotoras Genéticas/efeitos dos fármacos , RNA Mensageiro/genética , Membrana Sinovial/citologia
5.
Ann Med Surg (Lond) ; 85(10): 4683-4688, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37811055

RESUMO

Background: Patients with bilateral lower limb deep venous thrombosis (DVT) have a higher risk of pulmonary thromboembolism (PTE) and mortality than patients with unilateral lower limb DVT. Preoperative dilatation of the soleal vein (SV) diameter is a predictor of postoperative DVT. The purpose of this study is to investigate the cutoff value for SV diameter as a risk factor for VTE development. Materials and methods: The authors examined 274 patients with unilateral THA who met the inclusion criteria in a retrospective study. The mean age of the patients was 65.7±11.2 years, with 70 males and 204 females. Bilateral lower limb vein ultrasonography was performed preoperatively and ~1 week after THA. The frequency and localization of DVT were investigated in postoperative ultrasonography. The patients were divided into three groups: no DVT (non-DVT), unilateral lower limb DVT (Uni-DVT), and bilateral lower limb DVT (Bi-DVT). The three groups were compared in terms of preoperative venous vessel maximum diameter. Results: There were 62 patients (22.6%) who had postoperative DVT. There are no symptomatic PTE patients. DVT was found in 44 patients (16.0%) of the Uni-DVT group and 18 patients (6.6%) of the Bi-DVT group. The SV maximum diameter was 6.41±1.79 mm in the non-DVT group, 7.06±2.13 mm in the Uni-DVT group, and 8.06±2.26 mm in the Bi-DVT group, with a significant difference (P=0.001) between the non-DVT and Bi-DVT groups. In the Bi-DVT group, the cutoff value for preoperative SV maximum diameter was 6.75 mm (95% CI: 0.625-0.831; P=0.001; sensitivity, 77.8%; specificity, 60.4%; area under the curve, 0.728). Conclusions: In THA, preoperative ultrasonography with a maximum SV diameter of 6.75 mm or greater was the risk of bilateral DVT leading to fatal PTE is increased.

6.
J Bone Miner Metab ; 30(4): 468-73, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22222419

RESUMO

The aim of this study was to determine the effect of increasing estrogen and decreasing androgen in males and increasing androgen and decreasing estrogen in females on bone metabolism in patients with gender identity disorder (GID). We measured and examined bone mineral density (BMD) and bone metabolism markers retrospectively in GID patients who were treated in our hospital. In addition, we studied the effects of treatment on those who had osteoporosis. Patients who underwent a change from male to female (MtF) showed inhibition of bone resorption and increased L2-4 BMD whereas those who underwent a change from female to male (FtM) had increased bone resorption and decreased L2-4 BMD. Six months after administration of risedronate to FtM patients with osteoporosis, L2-4 BMD increased and bone resorption markers decreased. These results indicate that estrogen is an important element with regard to bone metabolism in males.


Assuntos
Antagonistas de Androgênios/efeitos adversos , Androgênios/efeitos adversos , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/metabolismo , Antagonistas de Estrogênios/efeitos adversos , Estrogênios/efeitos adversos , Procedimentos de Readequação Sexual/efeitos adversos , Adulto , Envelhecimento , Androgênios/sangue , Biomarcadores/sangue , Densidade Óssea/efeitos dos fármacos , Reabsorção Óssea/induzido quimicamente , Reabsorção Óssea/prevenção & controle , Difosfonatos/uso terapêutico , Estrogênios/sangue , Estrogênios/uso terapêutico , Feminino , Humanos , Japão , Masculino , Osteoporose/induzido quimicamente , Osteoporose/tratamento farmacológico , Osteoporose/prevenção & controle , Estudos Retrospectivos , Transexualidade/sangue , Transexualidade/complicações , Transexualidade/metabolismo , Adulto Jovem
8.
Sci Rep ; 10(1): 6561, 2020 04 16.
Artigo em Inglês | MEDLINE | ID: mdl-32300128

RESUMO

X-ray Talbot-Lau interferometry is one of the x-ray phase imaging methods that has high sensitivity in depicting soft tissues. Unlike earlier x-ray phase imaging methods that required particular types of x-ray sources, such as a synchrotron or a micro-focus x-ray tube, x-ray Talbot-Lau interferometry enables to perform clinical x-ray phase imaging using a conventional x-ray source with a relatively compact configuration. We developed an apparatus to depict cartilage in the metacarpophalangeal joints of the hands. In addition, we examined the apparatus performance by applying it to healthy volunteers and patients with rheumatoid arthritis (RA). Cartilage deformation, which is thought to be a precursor of destruction of the joints, was successfully depicted by the apparatus, suggesting a potential early diagnosis of RA.


Assuntos
Artrite Reumatoide/diagnóstico por imagem , Cartilagem/diagnóstico por imagem , Imageamento Tridimensional , Interferometria , Adulto , Idoso , Idoso de 80 Anos ou mais , Artrite Reumatoide/patologia , Cartilagem/patologia , Estudos de Casos e Controles , Feminino , Humanos , Articulações/diagnóstico por imagem , Articulações/patologia , Masculino , Pessoa de Meia-Idade , Raios X , Adulto Jovem
9.
J Orthop Res ; 35(9): 2007-2016, 2017 09.
Artigo em Inglês | MEDLINE | ID: mdl-27813260

RESUMO

To reduce the production of wear particles and subsequent aseptic loosening, we created a human articular cartilage-mimicked surface for a highly cross-linked polyethylene liner, whose surface grafted layer consisted of a biocompatible phospholipid polymer, poly(2-methacryloyloxyethyl phosphorylcholine). Although our previous in vitro findings showed that poly(2-methacryloyloxyethyl phosphorylcholine)-grafted particles were biologically inert and caused no subsequent bone resorptive responses, and poly(2-methacryloyloxyethyl phosphorylcholine) grafting markedly decreased wear in hip joint simulator tests, the clinical safety, and in vivo wear resistance of poly(2-methacryloyloxyethyl phosphorylcholine)-grafted highly cross-linked polyethylene liners remained open to question. Therefore, in the present study, we evaluated clinical and radiographic outcomes of poly(2-methacryloyloxyethyl phosphorylcholine)-grafted highly cross-linked polyethylene liners 5 years subsequent to total hip replacement in 68 consecutive patients. No reoperation was required for any reason, and no adverse events were associated with the implanted liners. The average Harris Hip Score increased from 38.6 preoperatively to 96.5 5 years postoperatively, and health-related quality of life, as indicated by the Short Form 36 Health Survey, improved. Radiographic analyses showed no periprosthetic osteolysis or implant migration. Between 1 and 5 years postoperatively, the mean steady-state wear rate was 0.002 mm/year, which represented a marked reduction relative to other highly cross-linked polyethylene liners, and appeared to be unaffected by patient-related or surgical factors. Although longer follow up is required, poly(2-methacryloyloxyethyl phosphorylcholine)-grafted highly cross-linked polyethylene liners improved mid-term clinical outcomes. The clinical safety and wear-resistance results are encouraging with respect to the improvement of long-term clinical outcomes with poly(2-methacryloyloxyethyl phosphorylcholine)-grafted highly cross-linked polyethylene liners. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:2007-2016, 2017.


Assuntos
Artroplastia de Quadril/instrumentação , Prótese de Quadril/estatística & dados numéricos , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Polietileno , Desenho de Prótese , Qualidade de Vida , Radiografia , Estudos Retrospectivos
10.
Arthritis Rheumatol ; 68(5): 1111-23, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26713842

RESUMO

OBJECTIVE: Synovial fibroblasts (SFs) produce matrix-degrading enzymes that cause joint destruction in rheumatoid arthritis (RA). Epigenetic mechanisms play a pivotal role in autoimmune diseases. This study was undertaken to elucidate the epigenetic mechanism that regulates the transcription of matrix metalloproteinases (MMPs) in RASFs. METHODS: MMP gene expression and histone methylation profiles in the MMP promoters were examined in RASFs. The effect of WD repeat domain 5 (WDR5) silencing on histone methylation and MMP gene expression in RASFs was analyzed. MMP gene expression, surface expression of the interleukin-6 (IL-6) receptor, phosphorylation of STAT-3, and binding of STAT-3 in the MMP promoters were investigated in RASFs stimulated with IL-6. RESULTS: The MMP-1, MMP-3, MMP-9, and MMP-13 genes were actively transcribed in RASFs. Correspondingly, the level of histone H3 trimethylated at lysine 4 (H3K4me3) was elevated, whereas that of H3K27me3 was suppressed in the MMP promoters in RASFs. The decrease in H3K4me3 via WDR5 small interfering RNA reduced the levels of messenger RNA for MMP-1, MMP-3, MMP-9, and MMP-13 in RASFs. Interestingly, IL-6 signaling significantly increased the expression of MMP-1, MMP-3, and MMP-13, but not MMP-9, in RASFs. Although the IL-6 signaling pathway was similarly active in RASFs and osteoarthritis SFs, STAT-3 bound to the MMP-1, MMP-3, and MMP-13 promoters, but not the MMP-9 promoter, after IL-6 stimulation in RASFs. CONCLUSION: Our findings indicate that histone methylation and STAT-3 regulate spontaneous and IL-6-induced MMP gene activation in RASFs. The combination of chromatin structure and transcription factors may regulate distinct arthritogenic properties of RASFs.


Assuntos
Artrite Reumatoide/genética , Fibroblastos/metabolismo , Regulação da Expressão Gênica/imunologia , Histonas/metabolismo , Interleucina-6/imunologia , Metaloproteinases da Matriz/genética , Fator de Transcrição STAT3/imunologia , Membrana Sinovial/citologia , Artrite Reumatoide/imunologia , Western Blotting , Estudos de Casos e Controles , Imunoprecipitação da Cromatina , Fibroblastos/imunologia , Citometria de Fluxo , Código das Histonas , Humanos , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/imunologia , Metaloproteinase 13 da Matriz/genética , Metaloproteinase 13 da Matriz/imunologia , Metaloproteinase 3 da Matriz/genética , Metaloproteinase 3 da Matriz/imunologia , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/imunologia , Metaloproteinases da Matriz/imunologia , Metilação , Osteoartrite do Joelho/genética , Osteoartrite do Joelho/imunologia , RNA Mensageiro/metabolismo , RNA Interferente Pequeno , Reação em Cadeia da Polimerase em Tempo Real , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ativação Transcricional
11.
Carbohydr Polym ; 99: 365-71, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24274519

RESUMO

The in vitro and in vivo antioxidant potentials of a polysaccharide isolated from aloe vera gel were investigated. Enzymatic extracts were prepared from aloe vera gel by using ten digestive enzymes including five carbohydrases and five proteases. Among them, the highest yield was obtained with the Viscozyme extract and the same extract showed the best radical scavenging activity. An active polysaccharide was purified from the Viscozyme extract using ethanol-added separation and anion exchange chromatography. Purified aloe vera polysaccharide (APS) strongly scavenged radicals including DPPH, hydroxyl and alkyl radicals. In addition, APS showed a protective effect against AAPH-induced oxidative stress and cell death in Vero cells as well as in the in vivo zebrafish model. In this study, it is proved that both the in vitro and in vivo antioxidant potentials of APS could be further utilized in relevant industrial applications.


Assuntos
Aloe/química , Antioxidantes/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Polissacarídeos/farmacologia , Amidinas/antagonistas & inibidores , Amidinas/farmacologia , Animais , Antioxidantes/química , Antioxidantes/isolamento & purificação , Compostos de Bifenilo/antagonistas & inibidores , Sobrevivência Celular/efeitos dos fármacos , Chlorocebus aethiops , Cromatografia por Troca Iônica , Embrião não Mamífero/efeitos dos fármacos , Glicosídeo Hidrolases/química , Radical Hidroxila/antagonistas & inibidores , Isoenzimas/química , Complexos Multienzimáticos/química , Oxidantes/antagonistas & inibidores , Oxidantes/farmacologia , Peptídeo Hidrolases/química , Picratos/antagonistas & inibidores , Polissacarídeos/química , Polissacarídeos/isolamento & purificação , Células Vero , Peixe-Zebra/fisiologia
20.
J Orthop Sci ; 8(4): 549-53, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12898309

RESUMO

We describe pathohistological findings of the human femoral head after it was grafted with hydroxyapatite (HA) and allogenic bone. The femoral head was removed because of the recurrence of a giant cell tumor 15 months after the graft. Histological investigation revealed that the entire surface of the HA granules was completely surrounded by the bone in the periphery of the grafted area; in some areas granules were partly in contact with the existing bone, and the rest were surrounded by fibrous tissue. There was no intervening layer of fibrous tissue between the granule surface and the bone where they were in direct contact. Pores were completely filled with fibrous tissue, partially filled with bone in the periphery of the pores, or completely filled with bone. Undecalcified histology revealed the formation of osteoid and ossification at the site where fibrous tissue infiltrated the pores. These findings indicated continued ingrowth of new bone into the HA pores. Under a scanning electron microscope, the surfaces of the granules showed clear demarcation in vitro, but it became less smooth, indicating in vivo changes. Although no foreign body reaction to the HA was noted anywhere, the HA surface appeared to be subject to a biodegradation process.


Assuntos
Materiais Biocompatíveis/farmacologia , Cerâmica/farmacologia , Durapatita/farmacologia , Cabeça do Fêmur/efeitos dos fármacos , Neoplasias Ósseas/cirurgia , Transplante Ósseo , Feminino , Cabeça do Fêmur/patologia , Cabeça do Fêmur/cirurgia , Tumor de Células Gigantes do Osso/cirurgia , Humanos , Pessoa de Meia-Idade , Porosidade
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