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1.
J Shoulder Elbow Surg ; 31(3): 601-607, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34656781

RESUMO

BACKGROUND: Immobilization in external rotation (ER) after a first-time shoulder dislocation was introduced to reduce the risk of recurrence compared with immobilization in internal rotation (IR), but its efficacy remains controversial. The purpose of this study was to determine the long-term effect of immobilization in ER after a first-time shoulder dislocation. METHODS: Between October 2000 and March 2004, 198 patients with a first-time anterior dislocation of the shoulder (average age 37) were randomly assigned to immobilization in ER (ER group = 104 shoulders) or IR (IR group = 94 shoulders) for 3 weeks. At an average 2-year follow-up, 159 patients (80.3%) were available for evaluation. In the current study, these 159 patients were further followed up and interviewed by telephone. The following items were evaluated: recurrent instability, apprehensive feeling, surgical intervention, limitation in the range of motion, return to sports, and the Single Assessment Numeric Evaluation (SANE) score. RESULTS: The average follow-up period was 18.2 years (range, 16-20 years). Fifty-six patients were available for follow-up with the follow-up rate of 35%. The number of recurrent patients was 6 of 27 (22%) in the ER group and 6 of 29 (21%) in the IR group (P = .889). The number of surgically stabilized patients was 3 of 27 (11%) in the ER group and 10 of 29 (34%) in the IR group (P = .038). In total, the recurrence rate was 33% (9 of 27) in the ER group and 55% (16 of 29) in the IR group (P = .100). Adding the surgical cases and those with the SANE score ≤70% as failure cases, the failure rate in the ER group (26%) was significantly lower than that in the IR group (52%) (P = .048). Among those who survived without surgical intervention, there were no significant differences in apprehensive feeling, return to sports, limited range of motion, and the SANE score between the groups. CONCLUSIONS: Immobilization in ER reduced the risk of surgical intervention compared with IR in the long term.


Assuntos
Instabilidade Articular , Luxação do Ombro , Articulação do Ombro , Seguimentos , Humanos , Imobilização , Lactente , Amplitude de Movimento Articular , Recidiva , Ombro , Luxação do Ombro/cirurgia , Articulação do Ombro/cirurgia
2.
Sci Rep ; 10(1): 20194, 2020 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-33214650

RESUMO

Weathered granite of ion-adsorption rare earth elements (REEs) ore collected at Jiangxi Province, China was investigated to identify the minerals abundant in REEs. The analyses of scanning electron microscopy (SEM)-energy dispersive spectrometry (EDS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for individual mineral particles of the weathered granite showed that kaolinitic particles formed by K-feldspar weathering contained large amounts of REEs. Scanning transmission electron microscopy (STEM)-EDS analyses revealed that the kaolinitic particles were mainly composed of kaolinite, illite and hematite. The elemental maps by Nano-SIMS for the kaolinitic particle clarified that La and Y are particularly concentrated in illite. The presence of illite presumably contributes to the formation of the REE accumulation zone in weathered granite. Furthermore, in the in-situ desorption experiment, nearly half the REEs (45.5%) remained in the kaolinitic particle after the treatment with 0.5 M ammonium sulfate solution. The desorption ratio of heavy REEs (HREEs: Gd-Lu) (60.4%) was lower than that of light REEs (LREEs: La-Eu) apart from Ce (69.0%). These results suggest that REEs form inner-sphere complexes on the kaolinitic particle. It can be assumed that the inner-sphere complexation suppresses the extraction ratio of REEs from the ores by ion-exchange treatment.

3.
ACS Omega ; 5(43): 28073-28079, 2020 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-33163789

RESUMO

The analytical efficacy of five gas mixers and five stabilizers on signal stabilization and washout time obtained for laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) was evaluated in the present study. In the case of gas mixers examined, a total of 95 patterns of their attitudes as well as different directions of the gas flows were examined, and it was found that the signal variation and the washout time were strongly dependent on these factors. Even in a simple Y-shaped fitting (Y-mixer), signal stability and washout time had large variations with respect to its different attitudes as well as gas flow directions. The shortest washout time for each gas mixer was almost the same ranging from 1.0 to 1.2 s. The signal variations observed were 11-15% of relative standard deviation (RSD) under optimum conditions for each gas mixer. The optimum condition of a Y-mixer for LA-ICPMS represented 11% RSD and 1.0 s for signal variation and washout time, respectively. In the case of stabilizers examined, almost all stabilizers improved signal variations from 11 to 3.0-9.3%, but washout times became longer than those of the only Y-mixer from 1.0 to 1.2-8.9 s. The important thing is that the signal stability and the washout time are trade-off correlations for gas mixers and stabilizers. A suitable gas mixer or a stabilizer on the trade-off line can be selected with respect to different applications. It was also observed that variations of both signal stability and washout time correlated with the volume of stabilizers despite their different inner structures; that is, a stable signal and longer washout time seemed to be observed when the volume of the chamber became larger. This suggested that the signal stabilization obtained by stabilizers was ascribable to not only elimination of larger particles from laser ablation but also particle mixing effect, which compensated signal variation.

4.
BMC Genomics ; 21(1): 671, 2020 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-32993496

RESUMO

BACKGROUND: Symbiosis is central to ecosystems and has been an important driving force of the diversity of life. Close and long-term interactions are known to develop cooperative molecular mechanisms between the symbiotic partners and have often given them new functions as symbiotic entities. In lichen symbiosis, mutualistic relationships between lichen-forming fungi and algae and/or cyanobacteria produce unique features that make lichens adaptive to a wide range of environments. Although the morphological, physiological, and ecological uniqueness of lichens has been described for more than a century, the genetic mechanisms underlying this symbiosis are still poorly known. RESULTS: This study investigated the fungal-algal interaction specific to the lichen symbiosis using Usnea hakonensis as a model system. The whole genome of U. hakonensis, the fungal partner, was sequenced by using a culture isolated from a natural lichen thallus. Isolated cultures of the fungal and the algal partners were co-cultured in vitro for 3 months, and thalli were successfully resynthesized as visible protrusions. Transcriptomes of resynthesized and natural thalli (symbiotic states) were compared to that of isolated cultures (non-symbiotic state). Sets of fungal and algal genes up-regulated in both symbiotic states were identified as symbiosis-related genes. CONCLUSION: From predicted functions of these genes, we identified genetic association with two key features fundamental to the symbiotic lifestyle in lichens. The first is establishment of a fungal symbiotic interface: (a) modification of cell walls at fungal-algal contact sites; and (b) production of a hydrophobic layer that ensheaths fungal and algal cells;. The second is symbiosis-specific nutrient flow: (a) the algal supply of photosynthetic product to the fungus; and (b) the fungal supply of phosphorous and nitrogen compounds to the alga. Since both features are widespread among lichens, our result may indicate important facets of the genetic basis of the lichen symbiosis.


Assuntos
Clorófitas/genética , Parmeliaceae/genética , Simbiose/genética , Parede Celular/metabolismo , Clorófitas/metabolismo , Genes Fúngicos , Genes de Plantas , Técnicas Microbiológicas , Nitrogênio/metabolismo , Parmeliaceae/metabolismo , Fósforo/metabolismo , Fotossíntese , Transcriptoma
5.
Sci Rep ; 10(1): 3281, 2020 02 24.
Artigo em Inglês | MEDLINE | ID: mdl-32094430

RESUMO

Spherical radioactive caesium (Cs)-bearing microparticles (CsMPs) were emitted during the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) accident in March, 2011. The emission source (timing) and formation process of these particles remain unclear. In this study, the isotopic ratios of uranium (235U and 238U) and caesium (133Cs, 134Cs, 135Cs, and 137Cs) isotopes in the five spherical CsMPs (ca. 2 µm in size) sampled at 50 km west of the FDNPP were determined using secondary ion mass spectrometry and laser ablation-ICPMS, respectively. Results showed that the 235U/238U ratios of CsMPs were homogeneous (1.93 ± 0.03, N = 4) and close to those estimated for the fuel cores in units 2 and 3, and that the Cs isotopic ratios of CsMP were identical to those of units 2 and 3. These results indicated that U and Cs in the spherical CsMPs originated exclusively from the fuel melt in the reactors. Based on a thorough review of literatures related to the detailed atmospheric releases of radionuclides, the flow of plumes from the FDNPP reactor units during the accident and the U and Cs isotopic ratio results in this study, we hereby suggest that the spherical CsMPs originate only from the fuel in unit 2 on the night of 14 March to the morning of 15 March. The variation range of the analysed 235U/238U isotopic ratios for the four spherical particles was extremely narrow. Thus, U may have been homogenised in the source through the formation of fuel melt, which ultimately evaporating and taken into CsMPs in the reactor and was released from the unit 2.

6.
Anal Sci ; 34(6): 739-742, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29887565

RESUMO

The mass transfer of additive elements during the sintering of barium titanate (BaTiO3) ceramic was examined by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) in the present study. An analytical sample consisting of two pellets of BaTiO3 with different concentrations of additive elements of manganese (Mn) and holmium (Ho) as well as silicon (Si) as a sintering reagent was prepared and measured by LA-ICP-MS with small laser irradiated diameter of 10 µm to evaluate the distributions and concentrations of additive elements in order to examine their mass transfers. As results, enrichments of Mn and Si as an additive element and a sintering reagent, respectively, were observed on the adhesive surface between two BaTiO3 pellets, even though Ho did not show a similar phenomenon. The mass transfers of additive elements of Mn and Ho were also examined, and Mn seemed to show a larger mass transfer than that of Ho during the sintering process for BaTiO3 ceramics. The results obtained in this study shows the effectives of LA-ICP-MS for the future improvement of MLCCs.

7.
Anal Chem ; 83(23): 8892-9, 2011 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-21999188

RESUMO

We have developed a new calibration technique for multielement determination and U-Pb dating of zircon samples using laser ablation-inductively coupled plasma mass spectrometry (ICPMS) coupled with galvanometric optics. With the galvanometric optics, laser ablation of two or more sample materials could be achieved in very short time intervals (~10 ms). The resulting sample aerosols released from different ablation pits or different solid samples were mixed and homogenized within the sample cell and then transported into the ICP ion source. Multiple spot laser ablation enables spiking of analytes or internal standard elements directly into the solid samples, and therefore the standard addition calibration method can be applied for the determination of trace elements in solid samples. In this study, we have measured the rare earth element (REE) abundances of two zircon samples (Nancy 91500 and Presovice) based on the standard addition technique, using a direct spiking of analytes through a multispot laser ablation of the glass standard material (NIST SRM612). The resulting REE abundance data show good agreement with previously reported values within analytical uncertainties achieved in this study (10% for most elements). Our experiments demonstrated that nonspectroscopic interferences on 14 REEs could be significantly reduced by the standard addition technique employed here. Another advantage of galvanometric devices is the accumulation of sample aerosol released from multiple spots. In this study we have measured the U-Pb age of a zircon sample (LMR) using an accumulation of sample aerosols released from 10 separate ablation pits of low diameters (~8 µm). The resulting (238)U-(206)Pb age data for the LMR zircons was 369 ± 64 Ma, which is in good agreement with previously reported age data (367.6 ± 1.5 Ma). (1) The data obtained here clearly demonstrate that the multiple spot laser ablation-ICPMS technique can become a powerful approach for elemental and isotopic ratio measurements in solid materials.

8.
J Shoulder Elbow Surg ; 17(6): 943-6, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18804388

RESUMO

Scapulohumeral rhythm (SHR) provides insight to neuromuscular control and fundamental biomechanics of the shoulder. This rhythm often is disrupted in pathologic shoulders. As the first step, we sought to quantify SHR in healthy subjects for diagnostic assessment of shoulder function. Ten healthy shoulders were studied. Three-dimensional models of the humerus and scapula were created from computed tomography scans. Dynamic shoulder motion was recorded by use of single-plane fluoroscopy during arm abduction with 0-kg and 3-kg handheld loads. Shoulder kinematics were quantified by use of model-based 3-dimensional-to-2-dimensional registration techniques. SHR decreased (more scapular motion) with increasing abduction. With a 3-kg load, scapulothoracic motion was significantly reduced through the range of 35 degrees to 45 degrees of glenohumeral motion. Muscular stabilization of the scapula increased with external loading, as shown by decreased SHR during early lifting. Dynamic scapular stabilization provides a critical platform for upper extremity activity.


Assuntos
Úmero/fisiologia , Movimento/fisiologia , Escápula/fisiologia , Articulação do Ombro/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Fluoroscopia , Humanos , Masculino
9.
Anal Sci ; 24(3): 345-53, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18332541

RESUMO

A laser ablation-inductively coupled plasma-mass spectrometric (LA-ICPMS) technique utilizing a titanium-sapphire (TiS) femtosecond laser (fs-laser) has been developed for elemental and isotopic analysis. The signal intensity profile, depth of the ablation pit and level of elemental fractionation were investigated in order to evaluate the analytical capability of the present fs-laser ablation-ICPMS technique. The signal intensity profile of (57)Fe, obtained from iron sulfide (FeS(2)), demonstrated that the resulting signal intensity of (57)Fe achieved by the fs-laser ablation was almost 4-times higher than that obtained by ArF excimer laser ablation under a similar energy fluence (5 J/cm(2)). In fs-laser ablation, there is no significant difference in a depth of the ablation pit between glass and zircon material, while in ArF laser ablation, the resulting crater depth on the zircon crystal was almost half the level than that obtained for glass material. Both the thermal-induced and particle size-related elemental fractionations, which have been thought to be main sources of analytical error in the LA-ICPMS analysis, were measured on a Harvard 91500 zircon crystal. The resulting fractionation indexes on the (206)Pb/(238)U (f(Pb/U)) and (238)U/(232)Th (f(U/Th)) ratios obtained by the present fs-laser ablation system were significantly smaller than those obtained by a conventional ArF excimer laser ablation system, demonstrative of smaller elemental fractionation. Using the present fs-laser ablation technique, the time profile of the signal intensity of (56)Fe and the isotopic ratios ((57)Fe/(54)Fe and (56)Fe/(54)Fe) have been measured on a natural pyrite (FeS(2)) sample. Repeatability in signal intensity of (56)Fe achieved by the fs-laser ablation system was significantly better than that obtained by ArF excimer laser ablation. Moreover, the resulting precision in (57)Fe/(54)Fe and (56)Fe/(54)Fe ratio measurements could be improved by the fs-laser ablation system. The data obtained here clearly demonstrate that, even with the fundamental wavelength (NIR operating at 780 nm), the fs-laser ablation system has the potential to become a significant tool for in-situ elemental and isotopic analysis of geochemical samples including heavy minerals and metallic materials.


Assuntos
Lasers , Espectrometria de Massas/métodos , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Isótopos de Ferro/análise , Isótopos , Chumbo/análise , Espectrometria de Massas/instrumentação , Sensibilidade e Especificidade , Silicatos/análise , Tório/análise , Fatores de Tempo , Urânio/análise , Zircônio/análise
10.
J Shoulder Elbow Surg ; 17(2): 319-22, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18162413

RESUMO

The purpose of this study was to investigate glenohumeral translation in-vivo during active shoulder abduction in the scapular plane. Three-dimensional (3D) models of 9 shoulders were created from CT scans. Fluoroscopic views aligned to the plane of the scapula were recorded during active arm abduction with neutral rotation. 3D motions were determined using model-based 3D-to-two-dimensional (2D) registration. Humeral translation was referenced to the glenoid center in the superior/inferior direction. The humerus moved an average of 1.7 mm superior with arm abduction, from an inferior location to the glenoid center. The humeral head was centered within 1 mm from the glenoid center above 80 degrees abduction. Variability in glenohumeral translation between shoulders decreased significantly from initial to final arm abduction. Our findings agree with some authors' observations of inferior-to-central translation of the humerus and behavior as a congruent ball and socket. We believe this information will help improve the understanding of shoulder function.


Assuntos
Articulação do Ombro/fisiologia , Adulto , Fenômenos Biomecânicos , Feminino , Fluoroscopia , Humanos , Masculino , Modelos Anatômicos , Amplitude de Movimento Articular , Tomografia Computadorizada por Raios X
11.
Arthroscopy ; 21(5): 632, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15891737

RESUMO

We describe 3 cases of an all-arthroscopic technique for repair of a humeral avulsion of the glenohumeral ligament (HAGL) lesion and the postoperative clinical outcomes. From a technical perspective, the most critical part of the surgeries was the anchor insertion at an optimal position on the humerus in order to achieve proper tension of the glenohumeral ligament. The arm-free beach-chair position, which facilitates maximum internal rotation, use of a 70 degrees angled arthroscope, and an anterior-inferior trans-subscapularis tendon portal were considered key factors to accomplish this procedure.


Assuntos
Traumatismos em Atletas/cirurgia , Úmero/inervação , Ligamento Colateral Médio do Joelho/lesões , Ligamento Colateral Médio do Joelho/cirurgia , Radiculopatia/cirurgia , Adulto , Artroscopia/métodos , Beisebol , Feminino , Humanos , Masculino
12.
Arthroscopy ; 21(5): 635, 2005 May.
Artigo em Inglês | MEDLINE | ID: mdl-15891740

RESUMO

Anterior glenoid fractures associated with glenohumeral instability are normally treated with open fixation of the fragment. However, recent technical development enables this procedure to be performed under arthroscopic control using screws or even suture anchors if the fragment is small enough. We developed a unique method of stabilizing a larger fragment with suture anchors and the use of a clear imaging method of three-dimensional computed tomography (3D-CT) with the humeral head eliminated, preoperatively and postoperatively. In the present article, we report a detailed method of arthroscopic stabilization for a consecutive series of 8 patients, with an average of 27% bone loss (fragment size) against the lower part of the circular glenoid portion, using suture anchors.


Assuntos
Fraturas Ósseas/cirurgia , Articulação do Ombro/cirurgia , Técnicas de Sutura , Artroscopia/métodos , Seguimentos , Humanos , Estudos Retrospectivos
13.
Arthroscopy ; 20 Suppl 2: 116-20, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15243443

RESUMO

In shoulder arthroscopy, cannulas with large diameters (7-9 mm) are commonly used both in the lateral decubitus and the beachchair position because they ensure the easy introduction of instruments into the intra-articular space and provide a clear arthroscopic view through the application of high intra-articular pressure. On the other hand, fluid extravasation and the resulting inconvenience due to the narrowing of the intra-articular working space are also obvious issues. Consequently, this makes arthroscopic stabilization surgery all the more challenging. To avoid these shortcomings of this procedure, we believe cannulas should be used only when necessary such as for knot tying and for transtendon portals. In this article, we report a unique and original method of arthroscopic Bankart repair in the beachchair position with limited use of cannulas of smaller diameter (5 mm) and its advantages over ordinary arthroscopic techniques using large-diameter cannulas in terms of preventing fluid extravasation and keeping a wide working space, which facilitates beneficial intra-articular techniques.


Assuntos
Artroscopia/métodos , Postura , Articulação do Ombro/cirurgia , Técnicas de Sutura , Humanos , Lesões do Ombro
14.
J Bone Joint Surg Am ; 85(5): 878-84, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12728039

RESUMO

BACKGROUND: Knowledge regarding the morphology of the glenoid rim is important when patients with recurrent anterior glenohumeral instability are assessed. Ordinary imaging techniques are not always sensitive enough to demonstrate the morphology of the glenoid rim accurately. We developed a method of three-dimensionally reconstructed computed tomography with elimination of the humeral head to evaluate glenoid morphology. The purpose of the present study was to quantify glenoid osseous defects and to define their characteristics in patients with recurrent anterior instability. METHODS: The morphology of the glenoid rim in 100 consecutive shoulders with recurrent unilateral anterior glenohumeral instability was evaluated on three-dimensionally reconstructed computed tomography images with the humeral head eliminated. The configuration of the glenoid rim was evaluated on both en face and oblique views. Concurrently, we also investigated seventy-five normal glenoids, including both glenoids in ten normal volunteers. Shoulders without an osseous fragment at the anteroinferior portion of the glenoid were compared with the contralateral shoulder in the same patient to determine if the glenoid morphology was normal. In shoulders with an osseous fragment, the fragment was evaluated quantitatively and its size was classified as large (>20% of the glenoid fossa), medium (5% to 20%), or small (<5%). Finally, all 100 shoulders were evaluated arthroscopically to confirm the presence of the lesion at the glenoid rim that had been identified with three-dimensionally reconstructed computed tomography. RESULTS: Investigation of the normal glenoids revealed no side-to-side differences. Investigation of the affected glenoids revealed an abnormal configuration in ninety shoulders. Fifty glenoids had an osseous fragment. One fragment was large (26.9% of the glenoid fossa), twenty-seven fragments were medium (10.6% of the glenoid fossa, on the average), and twenty-two were small (2.9% of the glenoid fossa, on the average). In the forty shoulders without an osseous fragment, the anteroinferior portion of the glenoid appeared straight on the en face view and it appeared obtuse or slightly rounded, compared with the normally sharp contour of the normal glenoid rim, on the oblique view, suggesting erosion or a mild compression fracture at this site. Arthroscopic investigation revealed a Bankart lesion in ninety-seven of the 100 shoulders and an osseous fragment in forty-five of the fifty shoulders in which an osseous Bankart lesion had been identified with the three-dimensionally reconstructed computed tomography. In the shoulders with distinctly abnormal morphology on three-dimensionally reconstructed computed tomography, the arthroscopic appearance of the anteroinferior portion of the glenoid rim was compatible with the appearance demonstrated by the three-dimensionally reconstructed computed tomography. CONCLUSIONS: We introduced a method to evaluate the morphology of the glenoid rim and to quantify the osseous defect in a simple and practical manner with three-dimensionally reconstructed computed tomography with elimination of the humeral head. Fifty percent of the shoulders with recurrent anterior glenohumeral instability had an osseous Bankart lesion; 40% did not have an osseous fragment but demonstrated loss of the normal circular configuration on the en face view and an obtuse contour on the oblique view, suggesting erosion or compression of the glenoid rim.


Assuntos
Instabilidade Articular/diagnóstico por imagem , Interpretação de Imagem Radiográfica Assistida por Computador , Articulação do Ombro/diagnóstico por imagem , Tomografia Computadorizada Espiral/métodos , Adolescente , Adulto , Artroscopia , Estudos de Casos e Controles , Feminino , Humanos , Instabilidade Articular/patologia , Masculino , Pessoa de Meia-Idade , Recidiva , Articulação do Ombro/patologia
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