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1.
Med Image Comput Comput Assist Interv ; 12265: 25-35, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33313603

RESUMO

A major challenge in clinical In-Vitro Fertilization (IVF) is selecting the highest quality embryo to transfer to the patient in the hopes of achieving a pregnancy. Time-lapse microscopy provides clinicians with a wealth of information for selecting embryos. However, the resulting movies of embryos are currently analyzed manually, which is time consuming and subjective. Here, we automate feature extraction of time-lapse microscopy of human embryos with a machine-learning pipeline of five convolutional neural networks (CNNs). Our pipeline consists of (1) semantic segmentation of the regions of the embryo, (2) regression predictions of fragment severity, (3) classification of the developmental stage, and object instance segmentation of (4) cells and (5) pronuclei. Our approach greatly speeds up the measurement of quantitative, biologically relevant features that may aid in embryo selection.

3.
Bone Joint J ; 98-B(5): 595-600, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27143728

RESUMO

AIMS: To investigate the longevity of uncemented fixation of a femoral component in total hip arthroplasty (THA) in patients with Dorr type C proximal femoral morphology. PATIENTS AND METHODS: A total of 350 consecutive uncemented THA in 320 patients were performed between 1983 and 1987, by a single surgeon using the Taperloc femoral component. The 63 patients (68 hips) with Dorr type C proximal femoral morphology were the focus of this review. The mean age of the patients was 69 years (24 to 88) and mean follow-up was 16.6 years (ten to 29). Survival analysis included eight patients (eight hips) who died without undergoing revision surgery prior to obtaining ten years follow-up. All 55 surviving patients (60 hips) were available for clinical assessment and radiographic review. As a comparator group, the survival and implant fixation in the remaining 282 THAs (257 patients) with Dorr type A and B morphology were evaluated. The mean age of these patients was 52 years (20 to 82). RESULTS: In the Dorr C patient group the mean Harris hip score improved from 51 points (21 to 69 points) pre-operatively to 89 (74 to 100) at final follow-up. No femoral component was loose by radiological criteria and osteolysis was only identified around two stems (3.3%). There was one revision (1.6%) of a well-fixed femoral component for sepsis at 11 years. The survival of the Taperloc femoral component at 20 years with revision for any reason as the endpoint was 98% (95% confidence interval; 87 to 99). A total of ten (3.5%) of the Dorr A and B patient group of 282 THAs required revision surgery. Only one (0.4%) for aseptic loosening. A total of two hips (1%) were loose by radiographic criteria and osteolysis occurred around 12 hips (4%). CONCLUSION: This study demonstrates that excellent fixation can be achieved using the Taperloc stem in patients with Dorr type A and B, and Dorr type C bone. TAKE HOME MESSAGE: The Taperloc stem demonstrated equivalent results in Dorr type A and B and Dorr type C bone. Cite this article: Bone Joint J 2016;98-B:595-600.


Assuntos
Artroplastia de Quadril , Fêmur/cirurgia , Prótese de Quadril , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Fêmur/diagnóstico por imagem , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Osteólise/epidemiologia , Complicações Pós-Operatórias , Reoperação/estatística & dados numéricos , Adulto Jovem
4.
Tissue Antigens ; 86(5): 382-3, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26467899

RESUMO

HLA-A*29:01:09 differs from A*29:01:01:01 by one nucleotide difference at nucleotide position 414.


Assuntos
Alelos , Antígenos HLA-A/genética , Povo Asiático , Teste de Histocompatibilidade , Humanos , Análise de Sequência de DNA
5.
Tissue Antigens ; 86(2): 122-33, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26176736

RESUMO

Complement component 2 (C2), an early member of the classical pathway, mainly participates in apoptotic cell clearance. We hypothesize that C2 polymorphism may confer genetic susceptibility to complement dysfunction in systemic lupus erythematosus (SLE). The major aim of our study was to investigate the clinical and serological associations of C2 variants in Chinese patients with SLE. The single-nucleotide polymorphism (rs2844455, G/A SNP) located in the intron region of C2 gene was genotyped by direct sequencing in 95 SLE patients and 95 matched normal control subjects. The gene expression profiles were generated by quantitative real-time polymerase chain reaction (PCR) and reverse transcription PCR. Our results showed that the AA genotype was observed more frequently in SLE patients than in normal control subjects (22.1% vs 9.5%, P < 0.05). The A allele was strongly associated with the occurrence of hair loss, photosensitivity and anti-cardiolipin antibodies; whereas, the G allele was associated with lower frequencies of these clinical presentations. Relative expression levels were significantly lower in patients with the AA genotype [median: 18.86, interquartile range (IQR) 11.36-22.43, P = 0.002] than in those with the GG genotype (35.76, IQR: 19.33-49.71). As expected, we confirmed the A allele as a risk factor for SLE development in a Chinese population, in contrast, the G allele might be a protective factor against the pathogenic autoantibody formation and cutaneous manifestations in SLE patients.


Assuntos
Alopecia/genética , Complemento C2/genética , Lúpus Eritematoso Sistêmico/genética , Fotofobia/genética , Polimorfismo de Nucleotídeo Único , Adulto , Alelos , Alopecia/etnologia , Alopecia/imunologia , Alopecia/patologia , Anticorpos Anticardiolipina/sangue , Povo Asiático , Estudos de Casos e Controles , Complemento C2/imunologia , Éxons , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Genótipo , Humanos , Íntrons , Lúpus Eritematoso Sistêmico/etnologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Masculino , Pessoa de Meia-Idade , Fotofobia/etnologia , Fotofobia/imunologia , Fotofobia/patologia
6.
Tissue Antigens ; 84(6): 574-5, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25346109

RESUMO

HLA-A*02:428 differs from A*02:06:01 by a non-synonymous mutation at codon 260 (CAT to GAT) in exon 4.


Assuntos
Alelos , Antígeno HLA-A2/genética , Mutação , Análise Mutacional de DNA , Feminino , Humanos , Masculino
7.
Value Health ; 17(7): A731, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-27202611
9.
J Appl Phys ; 113(3): 33706, 2013 Jan 21.
Artigo em Inglês | MEDLINE | ID: mdl-23405036

RESUMO

The intrinsic oxygen-vacancies and the extrinsic dopants are two major fundamental free-carrier sources for the extrinsic conducting oxides, such as Sn-doped In(2)O(3). Yet, the individual contributions of the above two free-carrier sources to the total carrier concentrations have never been unraveled. A carrier-concentration separation model is derived in this work, which can define the individual contributions to the total carrier concentration from the intrinsic oxygen-vacancies and the extrinsic dopants, separately. The individual contributions obtained from the present carrier-concentration separation model are verified by the two-state trapping model, photoluminescence, and positron annihilation lifetime (PAL) spectroscopy. In addition, the oxygen-vacancy formation energy of the Sn:In(2)O(3) thin film is determined to be 0.25 eV by PAL spectroscopy.

10.
Opt Express ; 19(21): 20916-29, 2011 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-21997101

RESUMO

Data fusion from disparate sensors significantly improves automated man-made target detection performance compared to that of just an individual sensor. In particular, it can solve hyperspectral imagery (HSI) detection problems pertaining to low-radiance man-made objects and objects in shadows. We present an algorithm that fuses HSI and LIDAR data for automated detection of man-made objects. LIDAR is used to define a set of potential targets based on physical dimensions, and HSI is then used to discriminate between man-made and natural objects. The discrimination technique is a novel HSI detection concept that uses an HSI detection score localization metric capable of distinguishing between wide-area score distributions inherent to natural objects and highly localized score distributions indicative of man-made targets. A typical man-made localization score was found to be around 0.5 compared to natural background typical localization scores being less than 0.1.


Assuntos
Óptica e Fotônica , Processamento de Sinais Assistido por Computador , Algoritmos , Análise por Conglomerados , Processamento Eletrônico de Dados , Entropia , Modelos Estatísticos , Reprodutibilidade dos Testes , Software
11.
Nanotechnology ; 22(28): 285301, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21625038

RESUMO

Highly ordered one-dimensional arrays of nanodots, or nanobeads, are fabricated by forming nanoripples and nanodots in sequence, entirely by ion-beam sputtering (IBS) of Au(001). This demonstrates the capability of IBS for the fabrication of sophisticated nanostructures via hierarchical self-assembly. The intricate nanobead pattern ideally serves to identify the governing mechanisms for the pattern formation: nonlinear effects, especially local redeposition and surface-confined transport, are essential both for the formation and the preservation of the one-dimensional order of the nanobead pattern.

12.
Br J Radiol ; 84(999): 210-5, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21325363

RESUMO

OBJECTIVE: Neointimal hyperplasia is a major complication of endovascular stent placement with consequent in-stent restenosis or occlusion. Improvements in the biocompatibility of stent designs could reduce stent-associated thrombosis and in-stent restenosis. We hypothesised that the use of a diamond-like carbon (DLC)-coated nitinol stent or a polyethylene glycol (PEG)-DLC-coated nitinol stent could reduce the formation of neointimal hyperplasia, thereby improving stent patency with improved biocompatibility. METHODS: A total of 24 stents were implanted, under general anaesthesia, into the iliac arteries of six dogs (four stents in each dog) using the carotid artery approach. The experimental study dogs were divided into three groups: the uncoated nitinol stent group (n = 8), the DLC-nitinol stent group (n = 8) and the PEG-DLC-nitinol stent group (n = 8). RESULTS: The mean percentage of neointimal hyperplasia was significantly less in the DLC-nitinol stent group (26.7±7.6%) than in the nitinol stent group (40.0±20.3%) (p = 0.021). However, the mean percentage of neointimal hyperplasia was significantly greater in the PEG-DLC-nitinol stent group (58.7±24.7%) than in the nitinol stent group (40.0±20.3%) (p = 0.01). CONCLUSION: Our findings indicate that DLC-coated nitinol stents might induce less neointimal hyperplasia than conventional nitinol stents following implantation in a canine iliac artery model; however, the DLC-coated nitinol stent surface when reformed with PEG induces more neointimal hyperplasia than either a conventional or DLC-coated nitinol stent.


Assuntos
Materiais Revestidos Biocompatíveis/uso terapêutico , Artéria Ilíaca/patologia , Neointima/prevenção & controle , Stents , Ligas/uso terapêutico , Animais , Implante de Prótese Vascular/instrumentação , Implante de Prótese Vascular/métodos , Cães , Hiperplasia/prevenção & controle , Neointima/patologia , Polietilenoglicóis/uso terapêutico , Stents/efeitos adversos
13.
J Bone Joint Surg Br ; 92(12): 1636-41, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21119167

RESUMO

We reviewed 123 second-generation uncemented total hip replacements performed on 115 patients by a single surgeon between 1993 and 1994. The acetabular component used in all cases was a fully porous-coated threaded hemispheric titanium shell (T-Tap ST) with a calcium ion stearate-free, isostatically compression-moulded polyethylene liner. The titanium femoral component used was a Taperloc with a reduced distal stem. No patient was lost to follow-up. Complete clinical and radiological follow-up was obtained for all 123 hips at a mean of 14 years (12 to 16). One femoral component was revised after a fracture, and three acetabular components for aseptic loosening. No additional femoral or acetabular components were judged loose by radiological criteria. Mild proximal femoral osteolysis was identified in two hips and minor acetabular osteolysis was present in four. The mean rate of penetration of the femoral head was 0.036 mm/year (0.000 to 0.227). These findings suggest that refinements in component design may be associated with excellent long-term fixation in cementless primary total hip replacement.


Assuntos
Artroplastia de Quadril/métodos , Prótese de Quadril , Adulto , Idoso , Idoso de 80 Anos ou mais , Artroplastia de Quadril/instrumentação , Cimentação , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Desenho de Prótese , Falha de Prótese , Reoperação , Análise de Sobrevida , Resultado do Tratamento
14.
Tissue Antigens ; 76(3): 253-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-20545904

RESUMO

A new HLA-B*9587 showed one nucleotide difference from B*15010101 at nucleotide 127 with substitution G-->C (codon 19 GAG-->CAG) resulting in a coding change from Glu to Gln (E19Q).


Assuntos
Doadores de Sangue , Antígenos HLA-B/genética , Alelos , Substituição de Aminoácidos , Sequência de Bases , Células da Medula Óssea , Antígeno HLA-B15 , Humanos , Coreia (Geográfico) , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Homologia de Sequência do Ácido Nucleico
18.
Acta Biomater ; 5(1): 249-56, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18753025

RESUMO

The hemocompatibility of plasma-treated, silicon-incorporated, diamond-like carbon (Si-DLC) films was investigated. Si-DLC films with a Si concentration of 2at.% were prepared on Si (100) or Nitinol substrates using a capacitively coupled radiofrequency plasma-assisted chemical vapor deposition method using a mixed gas of benzene (C(6)H(6)) and diluted silane (SiH(4):H(2)=10:90). The Si-DLC films were then treated with O(2), CF(4) or N(2) glow discharge for surface modification. The plasma treatment revealed an intimate relationship between the polar component of the surface energy and its hemocompatibility. All in vitro characterizations, i.e. protein absorption behavior, activated partial thromboplastin time measurement and platelet adhesion behavior, showed improved hemocompatibility of the N(2-)- or O(2)-plasma-treated surfaces where the polar component of the surface energy was significantly increased. Si-O or Si-N surface bonds played an important role in improving hemocompatibility, as observed in a model experiment. These results support the importance of a negatively charged polar component of the surface in inhibiting fibrinogen adsorption and platelet adhesion.


Assuntos
Carbono/química , Diamante/química , Silício/química , Adsorção , Albuminas/química , Ligas/química , Humanos , Modelos Estatísticos , Nitrogênio/química , Oxigênio/química , Tempo de Tromboplastina Parcial , Adesividade Plaquetária , Propriedades de Superfície , Fatores de Tempo , Água
19.
Tissue Antigens ; 72(6): 568-77, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19000142

RESUMO

Microarray technology makes high-throughput genotyping possible by permitting the simultaneous analysis of large sets of genes on a small reaction slide. Human leukocyte antigen (HLA) loci showing high polymorphisms are suitable targets for microarray. In this study, we developed a microarray kit with newly designed oligonucleotide probes for the genotyping of HLA-A and -DRB1. In total, 42 probes were designed to hybridize to polymorphic sites for HLA-A and 36 for HLA-DRB1. Asymmetric polymerase chain reaction (PCR) using four primers was performed to amplify exon 2 of HLA-DRB1, whereas symmetric PCR was performed to amplify both exons 2 and 3 of HLA-A. Evaluation of performance using samples from 138 Koreans disclosed consistent microarray results with all sequence-based typing at the low-resolution level. Despite the occurrence of ambiguities in 35 HLA-A (25.4%) and 5 HLA-DRB1 (3.6%) cases, correct genotypes were assigned with high certainty by referring to allele distribution in Koreans. These data clearly indicate that our newly developed microarray kit is optimal in determining correct genotypes at the low-resolution level in Koreans.


Assuntos
Antígenos HLA-A/genética , Antígenos HLA-DR/genética , Análise de Sequência com Séries de Oligonucleotídeos/métodos , População/genética , Genótipo , Cadeias HLA-DRB1 , Humanos , Coreia (Geográfico) , Sensibilidade e Especificidade
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