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1.
Sensors (Basel) ; 21(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34770404

RESUMO

In this study, an acoustic emission (AE) sensor was fabricated using lead-free Ba(Zr0.2Ti0.8)O3-0.5(Ba0.7Ca0.3)TiO3 (BZT-BCT) ceramics. The acoustic and electromechanical properties of the AE sensor were determined by the shapes of the piezoelectric ceramics. To optimize the AE sensor performance, the shapes of the ceramics were designed according to various diameter/thickness ratios (D/T) = 0.5, 1.0, 1.5, 2.0, 2.5, 3.0. The BZT-BCT ceramic with D/T = 1.0 exhibited excellent values of a piezoelectric charge coefficient (d33), piezoelectric voltage coefficient (g33), and electromechanical coupling factor (kp), which were 370 (pC/N), 11.3 (10-3 Vm/N), and 0.58, respectively. Optimum values of resonant frequency (fr) = 172.724 (kHz), anti-resonant frequency (fa) = 196.067 (kHz), and effective electromechanical coupling factor (keff) = 0.473 were obtained for the manufactured BZT-BCT ceramic with D/T = 1.0. The maximum sensitivity and frequency of the AE sensor made of the BZT-BCT ceramic with a D/T ratio of 1.0 were 65 dB and 30 kHz, respectively.


Assuntos
Cerâmica , Transdutores , Acústica , Desenho de Equipamento , Titânio
2.
Korean J Parasitol ; 58(2): 195-200, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32418390

RESUMO

Soil-transmitted helminths, including Ascaris lumbricoides and Trichuris trichiura, are important intestinal parasites mostly affecting younger people in developing countries. In 2014-2015, we performed mass fecal examinations targeting a total of 2,227 schoolchildren in 3 districts (South Dagon, North Dagon, and Hlaing-thar-yar) of Yangon Region, Myanmar, using the Kato-Katz thick smear technique. The egg positive children were subjected to a mass drug administration (MDA) using a single oral dose of 400 mg albendazole. The pre-treatment egg positive rate (EPG/person) of A. lumbricoides averaged 17.2% (15,532); it was 25.2% (21,796), 14.2% (11,816), and 12.8% (12,983) in 3 districts, respectively, and that of T. trichiura averaged 19.4% (1,074), and was 24.1% (1,040), 12.3% (852), and 21.2% (1,330) in 3 districts, respectively. Follow-up fecal examinations performed 4 months post-MDA revealed considerable decreases of A. lumbricoides prevalence (EPG/person) to av. 8.3% (12,429), and 13.7% (17,640), 8.0% (7,797), and 4.5% (11,849) in 3 districts, respectively. However, T. trichiura did not show any recognizable decrease in the prevalence (EPG/person) remaining at av. 18.2% (862), and 18.5% (888), 11.5% (812), and 23.3% (887) in 3 districts, respectively. The results demonstrated difficulty in short-term control of T. trichiura by MDA using albendazole and suggested necessity of either a long-term MDA (>10 years) or changing the albendazole regimen into 2~3-day course (total 800 or 1,200 mg), or using an alternative drug/drug combination.


Assuntos
Albendazol/administração & dosagem , Ascaríase/tratamento farmacológico , Ascaríase/parasitologia , Ascaris lumbricoides , Administração Massiva de Medicamentos , Animais , Ascaríase/epidemiologia , Criança , Humanos , Mianmar/epidemiologia
3.
Allergol Int ; 69(3): 429-436, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31883634

RESUMO

BACKGROUND: We aimed to evaluate the influence of cold airflow from the air conditioner on skin barrier function and filaggrin degradation products (FDPs) in children with atopic deramtitis (AD). METHODS: In a case-control study, 28 children with AD and 12 normal children without AD were exposed to one of two air conditioner modes (conventional or wind-free) for 2 h. Skin temperature, transepidermal water loss (TEWL), and skin pH were measured on right cheek and forearm at pre- and post-exposure time points. We also measured filaggrin and FDPs from the volar surface of the forearm. RESULTS: In AD patients, skin temperature on the forearm decreased after exposure to the conventional and wind-free modes (P < 0.001 and P = 0.026), and TEWL on the cheek and the forearm decreased in the wind-free mode (P = 0.037 and 0.002). Skin pH on the cheek increased only after exposure to the conventional mode in AD group (P = 0.002). However, no changes in TEWL and skin pH were found after exposure to either the conventional or the wind-free mode in the control group. In AD children, the levels of pyrrolidone carboxylic acid (PCA) and cis-urocanic acid (UCA) were reduced only after exposure to the conventional mode (all P = 0.033). The percent changes of PCA and cis-UCA were higher in the AD group than those in the control group after exposure to conventional mode (P = 0.029 and 0.046). CONCLUSIONS: Skin barrier function in children with AD may be altered by the exposure to cold airflow from a conventional air conditioner.


Assuntos
Temperatura Baixa , Dermatite Atópica/etiologia , Dermatite Atópica/metabolismo , Suscetibilidade a Doenças , Exposição Ambiental/efeitos adversos , Concentração de Íons de Hidrogênio , Proteínas de Filamentos Intermediários/metabolismo , Biomarcadores , Estudos de Casos e Controles , Criança , Dermatite Atópica/diagnóstico , Epiderme/imunologia , Epiderme/metabolismo , Epiderme/patologia , Proteínas Filagrinas , Humanos , Pele/imunologia , Pele/metabolismo , Pele/patologia , Temperatura Cutânea
4.
J Arthroplasty ; 32(6): 1965-1969, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28258831

RESUMO

BACKGROUND: The purpose of the study is to evaluate the radiologic and functional results of greater trochanteric reattachment using the third-generation cable plate system in revision total hip arthroplasty (THA). METHODS: A total of 47 trochanteric fixations (27 men and 18 women; mean age of 60.2 years) using the third-generation cable plate system in revision THA were retrospectively evaluated. The mean follow-up was 80.4 months (range 27-148 months). The osteotomized greater trochanter was reattached using the Cable-Ready system (Zimmer, Warsaw, IN) and the Dall-Miles cable system (Stryker, Mahwah, NJ). The clinical results with Harris hip score, visual analog scale, and radiologic outcomes were evaluated. RESULTS: The mean Harris hip score was improved from 55.7 (range 17-72) preoperatively to 90.8 (range 68-100; P = .001) postoperatively, and the mean pain score was improved from 6.6 (range 3-10) to 2.5 (range 0-6; P = .001), respectively. Nonunion was observed in 6 hips (12.7%). Migration of the osteotomized greater trochanteric fragment (>1 cm) was seen in 8 hips (17.0%). Cable breakage occurred in 13 cases (27.6%). Although 5 cable plate systems were removed, there was no need for reattachment of the greater trochanter in this study. CONCLUSION: This study showed a relatively high incidence of radiologic failure after greater trochanteric reattachment using the cable plate system in revision THA, although reattachments were not required and clinical outcome was relatively satisfactory. Periodic and close observation for the early detection of failure is necessary.


Assuntos
Artroplastia de Quadril/instrumentação , Artroplastia de Quadril/métodos , Placas Ósseas , Fêmur/cirurgia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença
5.
J Arthroplasty ; 32(5): 1576-1580, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-28139342

RESUMO

BACKGROUND: The purpose of the study was to evaluate the implant positions and clinical results of revision total hip arthroplasty (THA) using an imageless navigation with the concept of combined anteversion. METHODS: A total of 40 cementless revision THAs (24 men and 16 women) using an imageless navigation with the concept of combined anteversion were retrospectively evaluated. The concept of combined anteversion was applied in cup positioning based on Widmer's equation (cup anteversion + 0.7 × stem anteversion). The mean follow-up period was 80.7 months. Postoperatively, the inclination of the cup was evaluated on standard anteroposterior view of the radiograph, and the anteversion of the cup and femoral stem was evaluated using computed tomography scan. A cup inclination of 40° ± 10° and combined anteversion of the cup and femoral stem of 37° ± 10° based on Widmer's equation were regarded as the "safe zone." RESULTS: The average anteversion of the revised femoral stems was 15.3° ± 2.9° (range, 9.5°-21.5°), whereas that of the remained femoral stems was 17.4° ± 9.7° (range, 4.2°-29.8°). The inclination, anteversion of the cup, and combined anteversion after revision THA were 42.3° ± 3.1° (range, 32.1°-48.2°), 25.0° ± 2.9° (range, 16.9°-29.5°), and 36.1° ± 3.4° (range, 27.2°-42.9°), respectively. Therefore, the position of the implants, relative to the safe zone, showed no outliers after the revision surgery. Neither dislocation nor osteolysis was observed after the surgery. CONCLUSION: Favorable results of this study indicate that imageless navigation helps the surgeon in placing the components of revision THA in the safe zone. This study also shows that when this safe zone is consistently obtained, then no postoperative dislocations were observed in these patients over the 6-year follow-up period.


Assuntos
Artroplastia de Quadril/métodos , Mau Alinhamento Ósseo/prevenção & controle , Prótese de Quadril , Cirurgia Assistida por Computador , Acetábulo/cirurgia , Adulto , Idoso , Artroplastia de Quadril/efeitos adversos , Mau Alinhamento Ósseo/etiologia , Feminino , Fêmur/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Reoperação , Estudos Retrospectivos
6.
Arch Environ Contam Toxicol ; 69(3): 269-78, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26135299

RESUMO

Microplastics in marine environments are of emerging concern due to their widespread distribution, their ingestion by various marine organisms, and their roles as a source and transfer vector of toxic chemicals. However, our understanding of their abundance and distribution characteristics in surface seawater (SSW) remains limited. We investigated microplastics in the surface microlayer (SML) and the SSW at 12 stations near-shore and offshore of the Korean west coast, Incheon/Kyeonggi region. Variation between stations, sampling media, and sampling methods were compared based on abundances, size distribution, and composition profiles of microsized synthetic polymer particles. The abundance of microplastics was greater in the SML (152,688 ± 92,384 particles/m(3)) than in SSW and showed a significant difference based on the sampling method for SSWs collected using a hand net (1602 ± 1274 particles/m(3)) and a zooplankton trawl net (0.19 ± 0.14 particles/m(3)). Ship paint particles (mostly alkyd resin polymer) accounted for the majority of microplastics detected in both SML and SSWs, and increased levels were observed around the voyage routes of large vessels. This indicates that polymers with marine-based origins become an important contributor to microplastics in coastal SSWs of this coastal region.


Assuntos
Monitoramento Ambiental , Plásticos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , República da Coreia , Poluição Química da Água/estatística & dados numéricos
7.
Arch Environ Contam Toxicol ; 69(3): 299-309, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-25864179

RESUMO

The presence and distribution characteristics of microplastics become a big issue due to the adverse effects on marine organisms caused by not only microplastics but any incorporated and/or adsorbed pollutants. Distribution of microplastics (50- to 5000-µm size) was determined for three sandy beaches on an isolated island in a high-tidal costal region to elucidate spatial distributions in relation to beach locations. The abundances of microplastics (n = 21) measured were 56-285,673 (46,334 ± 71,291) particles/m(2) corresponding to the highest level globally. Out of observed polymer types, expanded polystyrene was overwhelmingly dominant. Although lying toward the estuary of the largest river in the country, the north-side beach contained a 100-fold lower abundance than two south-side beaches that faced southerly wind and currents that were prevalent throughout the study season. In addition, distinct differences between the beaches on either side were also present in terms of size distribution and spatial homogeneity of microplastics on the same beach. Winds and currents are therefore considered to be the driving forces in the distribution of microplastics.


Assuntos
Monitoramento Ambiental , Plásticos/análise , Água do Mar/química , Poluentes Químicos da Água/análise , Praias , República da Coreia , Movimentos da Água
8.
Medicine (Baltimore) ; 102(6): e32800, 2023 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-36820543

RESUMO

INTRODUCTION: Hypophosphatasia (HPP) is a genetic disease caused by loss-of-function mutations in ALPL, which encodes tissue-nonspecific alkaline phosphatase (ALP). Early diagnosis and treatment of perinatal and infantile HPP are important because of their high mortality rates. Enzyme replacement therapy (ERT) using human recombinant tissue-nonspecific ALP asfotase alfa was introduced in Korea in 2016. We report the first experience of ERT over 6 years for perinatal lethal and infantile HPP in Korea. PATIENT CONCERNS: The first patient was a 6-week-old Korean boy with a failure to thrive. The second patient was an 8-day-old Korean-Uzbek body with generalized tonic-clonic seizure with cyanosis. DIAGNOSES: HPP was suspected in both patients because of the very low level of ALP activity and rachitic findings on radiographs, and the disease was confirmed by Sanger sequencing of the ALPL gene. INTERVENTION: The first patient with infantile HPP started ERT at 21 months of age and the second patient with perinatal HPP started ERT at 30 days of age. Both patients received asfotase alfa (2 mg/kg 3 times per week subcutaneously, adjusted to 3 mg/kg 3 times per week if required) for 6 years. OUTCOMES: After 6 years of ERT, radiographic findings and growth standard deviation scores improved in both patients. The second patient showed no evidence of rickets after 3 years of ERT. Mechanical respiratory support and supplemental oxygen were not required after 4.5 years of treatment in the first patient and at 2 months after treatment in the second patient. CONCLUSION: Among the 2 patients, the patient who started ERT early had a much better prognosis despite a more severe initial clinical presentation. Our results suggest that early diagnosis and prompt treatment play an important role in improving long-term prognosis and avoiding morbidity and premature mortality in patients with perinatal and infantile HPP.


Assuntos
Hipofosfatasia , Humanos , Masculino , Fosfatase Alcalina/uso terapêutico , Terapia de Reposição de Enzimas/métodos , Hipofosfatasia/tratamento farmacológico , Hipofosfatasia/genética , Prognóstico , Proteínas Recombinantes de Fusão/uso terapêutico , República da Coreia , Recém-Nascido , Lactente
9.
J Nanosci Nanotechnol ; 12(4): 3252-5, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22849099

RESUMO

Yttria-stabilized zirconia (YSZ) layers of various thicknesses were designed and introduced before Pr0.7Ca0.3MnO3 (PCMO) film was deposited on W bottom electrodes with a submicron via-hole structure. By changing the thickness of the YSZ barrier layer (3, 5, 9, and 13 nm), a tunable memory window can be realized while low power consumption (P(max) < 4 microW) is maintained. Resistive switching (RS) in a Pt/PCMO/YSZ/W stack with a thin YSZ layer can be ascribed to an oxidation/reduction reaction caused by a ring-type PCMO/W contact, while RS with a thick YSZ layer may be related to oxygen migration across the YSZ layer between the PCMO film and the W bottom electrode and the increase (decrease) of the effective tunnel barrier height of the YSZ layer. Excellent RS behavior characteristics, such as a large R(HRS)/R(LRS) ratio (> 10(3)), die-to-die uniformity, sweeping endurance, and a retention time of more than 10(3) s, can be obtained by optimizing the thickness of YSZ layer.

10.
Nanotechnology ; 22(25): 254023, 2011 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-21572200

RESUMO

We demonstrated analog memory, synaptic plasticity, and a spike-timing-dependent plasticity (STDP) function with a nanoscale titanium oxide bilayer resistive switching device with a simple fabrication process and good yield uniformity. We confirmed the multilevel conductance and analog memory characteristics as well as the uniformity and separated states for the accuracy of conductance change. Finally, STDP and a biological triple model were analyzed to demonstrate the potential of titanium oxide bilayer resistive switching device as synapses in neuromorphic devices. By developing a simple resistive switching device that can emulate a synaptic function, the unique characteristics of synapses in the brain, e.g. combined memory and computing in one synapse and adaptation to the outside environment, were successfully demonstrated in a solid state device.


Assuntos
Potenciais de Ação/fisiologia , Biomimética/métodos , Memória , Nanoestruturas/química , Nanotecnologia/instrumentação , Plasticidade Neuronal/fisiologia , Tamanho da Partícula , Titânio/química , Condutividade Elétrica , Modelos Biológicos , Sinapses
11.
J Arthroplasty ; 26(7): 1045-9, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21570247

RESUMO

In elderly patients, osteoporosis can complicate revision total hip arthroplasty (THA). The SLR-Plus (Smith & Nephew, Memphis, TN) revision stem has a tapered, press-fit design, which we hypothesized could enhance stability in this population. Accordingly, we retrospectively analyzed data for 48 elderly patients who underwent revision THA using the SLR-Plus stem. The patients had a mean age of 66.5 years (range, 60-81 years) at surgery. They were monitored for a mean of 5.6 years (range, 3.4-8.0 years) after surgery. The mean Harris Hip Score improved from 67.8 to 91.6. No infection, dislocation, osteolysis, or stress shielding around stem were observed after surgery. The survivorship at an average of 5.6-year follow-up was 98%. These favorable results indicate that the SLR-Plus stem is useful in revision THA in elderly patients.


Assuntos
Artroplastia de Quadril , Prótese de Quadril , Idoso , Idoso de 80 Anos ou mais , Feminino , Articulação do Quadril/diagnóstico por imagem , Humanos , Masculino , Pessoa de Meia-Idade , Falha de Prótese , Radiografia , Reoperação
12.
Front Endocrinol (Lausanne) ; 12: 687834, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34194397

RESUMO

Background/purpose: Graves' disease (GD) is the most common cause of thyrotoxicosis in children and adolescents. There is some debate regarding the optimal treatment and predicting factors of remission or relapse in children and adolescents with GD. In this study, we report a retrospective study of 195 children and adolescents with GD treated at a single tertiary institution in Korea. Methods: This study included children and adolescents with GD diagnosed before 19 years of age from January of 2000 to October of 2020. The diagnosis of GD was based on clinical features, high thyroxine (FT4), suppressed thyroid-stimulating hormone, and a positive titer of thyrotropin receptor antibodies. Remission was defined as maintenance of euthyroid status for more than six months after discontinuing antithyroid drug (ATD). Results: A total of 195 patients with GD were included in this study. The mean age at diagnosis was 12.9 ± 3.2 years, and 162 patients (83.1%) were female. Among all 195 patients, five underwent thyroidectomy and three underwent radioactive iodine therapy. The mean duration of follow-up and ATD treatment were 5.9 ± 3.8 years and 4.7 ± 3.4 years, respectively. The cumulative remission rates were 3.3%, 19.6%, 34.1%, 43.5%, and 50.6% within 1, 3, 5, 7, and 10 years of starting ATD, respectively. FT4 level at diagnosis (P = 0.001) was predicting factors for remission [HR, 0.717 (95% CI, 0.591 - 0.870), P = 0.001]. Methimazole (MMI)-related adverse events (AEs) occurred in 11.3% of patients, the most common of which were rash and hematologic abnormalities. Of a total of 26 AEs, 19 (73.1%) occurred within the first month of taking MMI. Conclusions: In this study, the cumulative remission rate increased according to the ATD treatment duration. Long-term MMI treatment is a useful treatment option before definite treatment in children and adolescents with GD.


Assuntos
Antitireóideos/uso terapêutico , Bócio/tratamento farmacológico , Doença de Graves/tratamento farmacológico , Metimazol/uso terapêutico , Propiltiouracila/uso terapêutico , Adolescente , Criança , Feminino , Humanos , Masculino , Indução de Remissão , Estudos Retrospectivos , Resultado do Tratamento
13.
Bioorg Med Chem Lett ; 18(23): 6135-7, 2008 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-18938074

RESUMO

The work is directed toward the synthesis of gold nanoparticles (Au NPs) coated with paramagnetic Gd-complex of DTPA-bis(amide) conjugate of glutathione (GdL) for use as a highly efficient MRI contrast agent. Well-dispersed spherical Au NPs coated with gadolinium complexes, abbreviated as Au@GdL, have been obtained; the mean size of Au@GdL is 5-7 nm, and the numbers of GdL are 1.36x10(4) per Au NP. Au@GdL exhibits high longitudinal (r1) and transverse (r2) relaxivities of 1.87x10(5) and 3.02x10(5) mM(-1) s(-1), respectively.


Assuntos
Meios de Contraste/química , Gadolínio DTPA/análogos & derivados , Glutationa , Ouro/química , Imageamento por Ressonância Magnética/métodos , Nanopartículas , Compostos Organometálicos/química , Gadolínio DTPA/química
14.
J Orthop Surg (Hong Kong) ; 26(2): 2309499018783913, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29945472

RESUMO

PURPOSE: The purpose of this study is to evaluate the clinical and radiologic outcomes after revision total hip arthroplasty (THA) using fourth-generation ceramic-on-ceramic (CoC) bearing surfaces. METHODS: A total of 52 revision THAs (28 men and 19 women) using the fourth-generation CoC bearing surfaces were retrospectively evaluated. Both acetabular cup and femoral stem were revised in all cases. The mean follow-up period was 7.3 years (range, 4.0-9.9 years). The clinical results with Harris hip score (HHS), Western Ontario McMaster Osteoarthritis Index (WOMAC), and radiologic outcomes were evaluated. RESULTS: At the final follow-up examination, the average HHS was 90.4 (range, 67-100). The average WOMAC pain and physical function score were 2.8 (range, 0-12) and 16.4 (range, 0-42), respectively. Complications were observed in 10 hips (19.2%). However, there were no bearing surface-related complications, and no cases of dislocation and squeaking. Retroacetabular pelvic osteolysis without cup loosening was observed in one hip at the final follow-up. However, no hip showed radiographic signs of cup loosening, vertical or horizontal acetabular cup migrations, and changes of inclinations during the follow-up period. CONCLUSION: Our data showed that clinical and radiologic outcomes after revision THA using fourth-generation CoC bearing were favorable. Hence, revision THA with the use of CoC bearing surfaces can be preferentially considered. Further studies with long-term follow-up data are warranted.


Assuntos
Artroplastia de Quadril/métodos , Cerâmica , Prótese de Quadril , Osteoartrite do Quadril/cirurgia , Adulto , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Reoperação , Estudos Retrospectivos , Fatores de Tempo , Resultado do Tratamento
15.
J Neurol Surg A Cent Eur Neurosurg ; 79(4): 273-278, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29684924

RESUMO

BACKGROUND AND STUDY AIM: Cortical screws were proposed as an alternative to the traditional pedicle screws. Diverse experimental results support the biomechanical superiority of cortical screws compared to pedicle screws. Laminectomy is often part of multilevel lumbar surgeries. Laminectomy might weaken the medial bony edge at the entry of the divergently oriented screw and, thereby, the screw purchase. This study investigated the biomechanical strength of lumbar cortical screw after laminectomy. OBJECTIVE: To compare the fixation strength of cortical screws and traditional pedicle screws after lumbar laminectomy. MATERIAL AND METHODS: A total of 120 pedicles from 60 lumbar vertebrae of 12 cadavers (8 men, 4 women) were assessed. The mean age of the cadavers was 73.4 ± 6.2 years (range: 62-82 years). Using a posterior midline approach, we inserted the traditional pedicle screws into one and the cortical screws into the other side of each vertebra. Laminectomy was performed after screw insertion. Vertical pullout strength and toggle strength testing were performed to compare the fixation strength between the two sides. RESULTS: After laminectomy, the pullout strength of the cortical screws was 718.92 ± 340.76 N, and that of the pedicle screws was 625.78 ± 287.10 N (p = 0.183). The toggle strength of the cortical screws was 544.83 ± 329.97 N; that of the pedicle screws was 613.17 ± 311.70 N (p = 0.145). No significant difference was found in biomechanical strength between the two types of screws. CONCLUSION: Despite laminectomy, lumbar cortical screws offers comparable pullout and toggle biomechanical strength as traditional pedicle screws.


Assuntos
Parafusos Ósseos , Laminectomia , Vértebras Lombares/cirurgia , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Parafusos Pediculares , Estresse Mecânico
16.
Sci Rep ; 8(1): 14146, 2018 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-30237430

RESUMO

In this study, electromechanical characteristics of (1-x) Bi0.5Na0.5TiO3-xSrTiO3 (ST26, x = 0.26)/(1-y) Bi0.5Na0.5TiO3-ySrTiO3 (ST10, y = 0.1) (matrix/seed) composites were studied. The ST26 (high relaxor phase) and ST10 (a relaxor ferroelectric (RF), high ferroelectric phase) composite with large (r-ST26-ST10) and small (t-ST26-ST10) grains exhibited frequency-related dielectric properties and large strain response at a low triggering electric field (an incipient piezoelectricity). It is ascribed to a matrix-seed effect originating from the inhomogeneous composition due to the presence of two phases. The r-ST26-ST10 composite sintered at 4 h, prominent material, showed a high normalized dynamic strain (d33*) of ~700 pm/V (large grains) with stable frequency dependence properties at a low field of 40 kV/cm. The properties of the r-ST26-ST10 composite exhibit less decay with frequency-related polarization and strain compared to those of t-ST26-ST10 composite. The increase in soaking time promotes the diffusion and homogenization of the microstructure in composites, leading to changes in the core-shell structure in the solid solution. The polarization and strain of the ST26-ST10 composites with the frequency are linked to the stability of the internal random fields created by non-ergodic relaxor phase of seed and the amount of phase change in the ergodic relaxor matrix.

17.
Front Nutr ; 5: 23, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29707542

RESUMO

The intestinal microbial communities play critical roles in various aspects of body function of the host. Prebiotics, such as dietary fiber, can affect health of the host by altering the composition of intestinal microbiota. Although brown seaweed Laminaria japonica is rich in dietary fiber, studies on its prebiotic potential are quite rare. In this study, basal diet (control), basal diet supplemented with dried L. japonica (DLJ), heat-treated dried L. japonica (HLJ), or heated dried L. japonica with added fructooligosaccharide (FHLJ) was fed to rats for 16 weeks. Serum concentrations of IgG, triglyceride, and cholesterol were measured. In addition, the intestinal microbiota composition was analyzed by high-throughput sequencing of 16S rRNA gene. As compared to the control group, DLJ, HLJ, and FHLJ groups showed significantly higher serum IgG concentration, but had lower weight gain and serum triglyceride concentration. Moreover, DLJ, HLJ, and FHLJ groups showed lower Fimicutes to Bacteroidetes ratio when compared with the control group. As compared with the control group, obesity-associated bacterial genera (Allobaculum, Turicibacter, Coprobacillus, Mollicute, and Oscilibacter), and the genera with pathogenic potentials (Mollicute, Bacteroides, Clostridium, Escherichia, and Prevotella) decreased while leanness-associated genera (Alistipes, Bacteroides, and Prevotella), and lactic acid bacterial genera (Subdoligranulum, Streptococcus, Lactobacillus, Enterococcus, and Bifidobacterium) increased in all treatment groups. On the contrary, butyric acid producing genera including Subdoligranulum, Roseburia, Eubacterium, Butyrivibrio, and Anaerotruncus increased significantly only in FHLJ group. The overall results support multiple prebiotic effects of seaweed L. japonica on rats as determined by body weight reduction, enhanced immune response, and desirable changes in intestinal microbiota composition, suggesting the great potential of L. japonica as an effective prebiotic for promotion of host metabolism and reduction of obesity in humans.

18.
Hip Pelvis ; 29(1): 1-14, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28316957

RESUMO

In total hip arthroplasty (THA), the accurate positioning of implants is the key to achieve a good clinical outcome. Computer-assisted orthopaedic surgery (CAOS) has been developed for more accurate positioning of implants during the THA. There are passive, semi-active, and active systems in CAOS for THA. Navigation is a passive system that only provides information and guidance to the surgeon. There are 3 types of navigation: imageless navigation, computed tomography (CT)-based navigation, and fluoroscopy-based navigation. In imageless navigation system, a new method of registration without the need to register the anterior pelvic plane was introduced. CT-based navigation can be efficiently used for pelvic plane reference, the functional pelvic plane in supine which adjusts anterior pelvic plane sagittal tilt for targeting the cup orientation. Robot-assisted system can be either active or semi-active. The active robotic system performs the preparation for implant positioning as programmed preoperatively. It has been used for only femoral implant cavity preparation. Recently, program for cup positioning was additionally developed. Alternatively, for ease of surgeon acceptance, semi-active robot systems are developed. It was initially applied only for cup positioning. However, with the development of enhanced femoral workflows, this system can now be used to position both cup and stem. Though there have been substantial advancements in computer-assisted THA, its use can still be controversial at present due to the steep learning curve, intraoperative technical issues, high cost and etc. However, in the future, CAOS will certainly enable the surgeon to operate more accurately and lead to improved outcomes in THA as the technology continues to evolve rapidly.

19.
Hip Pelvis ; 29(1): 35-43, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-28316961

RESUMO

PURPOSE: The treatment of infected revision total hip arthroplasty (THA) is very challenging due to retained revision prosthesis, poor bone stock and soft tissue condition derived from previous revision surgeries, and comorbidities. The purpose of this study was to investigate the effectiveness and short-term outcomes of aggressive debridement and use of antibiotic-loaded cement beads with retention of the prosthesis for acute delayed or late infection of revision THAs. MATERIALS AND METHODS: Ten consecutive patients with symptoms or signs of less than one-week evolution and well-fixed prostheses, were treated with this procedure and a postoperative course of organism-specific antibiotics for a minimum of 6 weeks. All hips presented with acute delayed or late infection of revision THAs. Patients with a mean age of 68.1 years (range, 59-78 years) underwent an average of 1.9 previous revision THAs (1-4) before the index surgery. The minimal follow-up was 2 years with a mean of 46.2 months (range, 24-64 months). RESULTS: There were 8 cures (80.0%) and 2 failures with no mortality during the study period. The 2 failures involved the same and resistant bacteria implicated in the primary infection (methicillin-resistant Staphylococcus aureus and Prevotella oralis, respectively). The mean Harris hip score was 65.2 (range, 26-83) and the mean visual analogue scale was 2.6 (range, 1-4) at final follow-up. CONCLUSION: With a favorable success rate and no mortality, our procedure may be considered a safe and effective alternative for the treatment of acute delayed or late infection of revision THAs with well-fixed prostheses.

20.
Hip Pelvis ; 29(4): 211-222, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29250494

RESUMO

Arthritis damages the cartilage within joints, resulting in degenerative changes, including loss of function and joint instability. Ankylosing spondylitis (AS) is a chronic inflammatory condition affecting the spine and bone-to-tendon attachment area within the sacroiliac joint leading to back pain and progressive spinal stiffness. In the final stages, AS causes hyperkyphosis-a condition closely tied to the human leukocyte antigen-B27 gene. Rheumatoid arthritis is a chronic, systemic autoimmune disease characterized by the simultaneous inflammation of the synovium of multiple joints, leading to joint damage (e.g., destruction, deformation and disability). In the past, nonsteroidal anti-inflammatory drugs or conventional disease-modifying antirheumatic drug (DMARDs) have been used for the treatment of these autoimmune diseases, but biologic DMARDs have recently been introduced with excellent results. Gout is a chronic inflammatory disease that causes an alteration of joints resulting in severe pain. Specifically, gout is associated with an accumulation of uric acid within the body resulting from dysregulated purine metabolism, causing recurrent paroxysmal inflammation in the joints. Allopurinol and febuxostat are the primary treatment options for individuals with gout. It is necessary to have an accurate understanding of the pathogenesis, pathological ecology and treatment of AS, rheumatoid arthritis, and gouty arthritis, which are the representative diseases that may cause inflammatory arthritis.

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