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1.
Artigo em Inglês | MEDLINE | ID: mdl-31059441

RESUMO

In content-based image retrieval (CBIR), one of the most challenging and ambiguous tasks are to correctly understand the human query intention and measure its semantic relevance with images in the database. Due to the impressive capability of visual saliency in predicting human visual attention that is closely related to the query intention, this paper attempts to explicitly discover the essential effect of visual saliency in CBIR via qualitative and quantitative experiments. Toward this end, we first generate the fixation density maps of images from a widely used CBIR dataset by using an eye-tracking apparatus. These ground-truth saliency maps are then used to measure the influence of visual saliency to the task of CBIR by exploring several probable ways of incorporating such saliency cues into the retrieval process. We find that visual saliency is indeed beneficial to the CBIR task, and the best saliency involving scheme is possibly different for different image retrieval models. Inspired by the findings, this paper presents two-stream attentive CNNs with saliency embedded inside for CBIR. The proposed network has two streams that simultaneously handle two tasks. The main stream focuses on extracting discriminative visual features that are tightly related to semantic attributes. Meanwhile, the auxiliary stream aims to facilitate the main stream by redirecting the feature extraction to the salient image content that human may pay attention to. By fusing these two streams into the Main and Auxiliary CNNs (MAC), image similarity can be computed as the human being does by reserving conspicuous content and suppressing irrelevant regions. Extensive experiments show that the proposed model achieves impressive performance in image retrieval on four public datasets.

2.
J Craniofac Surg ; 29(3): 774-777, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29381629

RESUMO

To explore a new surgical approach for chin augmentation using a prosthesis with 3 intraoral vertical incisions whereby placement of the prosthesis is more convenient and accurate, with fewer postoperative complications. Following the anatomic characteristics of the chin, a bilateral mucosal vertical incision and a median observation incision are made. The V-shaped mark on the upper side of the prosthesis can be seen through the observation incision after it is placed from the lateral incision into the predesigned compartment. The incision can be sutured if there is no bleeding in the operation area. Surgery performed in all 19 patients with mild microgenia with 6 to 12 months of follow-up resulted in satisfactory chin and face shape without any complications. The application of this novel method can correct McCarthy type I microgenia with more accurate positioning, less possibility of bilateral sideways and/or up/down movement, and fewer complications.


Assuntos
Queixo/cirurgia , Mentoplastia/métodos , Adolescente , Adulto , Queixo/anormalidades , Estética , Feminino , Mentoplastia/efeitos adversos , Humanos , Masculino , Complicações Pós-Operatórias , Próteses e Implantes , Adulto Jovem
3.
Molecules ; 22(12)2017 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-29182558

RESUMO

Plants or plant-derived products have been routinely used in several traditional medicine systems for vitiligo treatment. It is well-known that melanogenesis can be promoted by certain flavonoid compounds isolated from the traditional Uyghur medicinal plant, Kaliziri. Therefore, Chalcones, one class of flavonoid compounds, has become an interesting target for the development of anti-vitiligo agents. A series of novel isoxazole chalcone derivatives have been designed, synthesized, and evaluated for biological activities by our group. Among them, derivative 1-(4-((3-phenylisoxazol-5-yl)methoxy)phenyl)-3-phenylprop-2-en-1-one (PMPP) was identified as a potent tyrosinase activator with better activity and lower toxicity than the positive control 8-methoxypsoralen (8-MOP) in this study. Further investigations revealed that Akt and GSK3ß were the signaling pathways involved in the hyperpigmentation of PMPP. Overall, these studies may provide a convenient and novel approach for the further development of anti-vitiligo agents.


Assuntos
Chalconas/farmacologia , Glicogênio Sintase Quinase 3 beta/metabolismo , Melaninas/biossíntese , Extratos Vegetais/farmacologia , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais/efeitos dos fármacos , beta Catenina/metabolismo , Animais , Chalconas/química , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Melanoma Experimental , Camundongos , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/química
4.
J Craniofac Surg ; 26(7): 2201-6, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26468810

RESUMO

Trans-sutural distraction osteogenesis (TSDO) has been successfully used to correct midfacial hypoplasia in growing patients for years. The effects of TSDO, however, remain difficult to predict in adult patients. The aim of this study was to determine the biologic basis for the age-related increase in difficulty of performing TSDO. A total of 45 male Sprague Dawley (SD) rats were obtained in 3 age groups: 4 weeks old (4W, N = 15), 3 months old (3M, N = 15), and 13 months old (13M, N = 15). The zygomaticomaxillary sutures (ZMS) were dissected, and their morphology was evaluated by histology and micro-computed tomography (micro-CT). Quantitative real-time polymerase chain reaction of the ZMS and blood samples taken from the abdominal aorta were also used to assess the effects of age at the molecular level. Compared with the 4W rats, the number of fibroblasts in the ZMS was decreased, the bone plate adjacent to the ZMS was thicker, and the texture was denser in the 13M rats. Micro-computed tomography analysis showed the density of the ZMS was significantly increased in the 13M group (P < 0.05). The density ratio of the ZMS to the adjacent bone was increased from 0.14:1 in the 4M group to 0.54:1 in the 13M group. The gene expression of osteocalcin (OC) was significantly lower at 13M than at 3M (P < 0.05). The OC and alkaline phosphatase (ALP) serum levels were significantly lower at 13M than at 4W (P < 0.05). During aging, the decreased osteogenesis activity both systemically and locally may be the biologic effect that limits the application of TSDO in older patients.


Assuntos
Envelhecimento/patologia , Suturas Cranianas/anatomia & histologia , Maxila/anatomia & histologia , Zigoma/anatomia & histologia , Envelhecimento/sangue , Fosfatase Alcalina/análise , Fosfatase Alcalina/sangue , Animais , Densidade Óssea/fisiologia , Contagem de Células , Fibroblastos/citologia , Masculino , Osteocalcina/análise , Osteocalcina/sangue , Osteoclastos/citologia , Osteogênese/fisiologia , Osteogênese por Distração/métodos , Osteoprotegerina/análise , Osteoprotegerina/sangue , Ligante RANK/análise , Ligante RANK/sangue , Ratos , Ratos Sprague-Dawley , Microtomografia por Raio-X/métodos
5.
J Chromatogr A ; 1076(1-2): 198-201, 2005 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-15974089

RESUMO

Rupestonic acid was purified for the first time by high-speed counter-current chromatography from a dichloromethane extract of the traditional Chinese medicinal plant Artemisia rupestris L. The separation was performed in two steps with a two-phase solvent system composed of n-hexane-ethyl acetate-methanol-water (6:4:3.5:6.5, v/v) with 0.5% acetic acid in stationary-phase. From 200 mg of the crude extract, 27.9 mg of rupestonic acid was obtained at over 98% purity as determined by HPLC analysis, and its chemical structure was confirmed by MS, 1H and 13C nuclear magnetic resonance.


Assuntos
Artemisia/química , Distribuição Contracorrente/métodos , Plantas Medicinais/química , Sesquiterpenos/isolamento & purificação , Azulenos , Cromatografia Líquida de Alta Pressão
6.
J Am Chem Soc ; 126(7): 2181-5, 2004 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-14971953

RESUMO

Two analogous classes of dendrimers with a single azobenzene moiety at the core have been prepared. Flexible benzyl aryl ether dendrimers 1a-e were obtained in good yields by direct alkylation of diphenolic azobenzene 3 with benzyl aryl ether dendrons [G-n]-Br (n = 0-4). In rigid dendrimers 2a-e, the azobenzene configurational switch was linked to phenylacetylene dendrons through acetylenic linkages to maintain the shape-persistent nature of these dendrimers. A comparison of these two different classes of dendrimers with azobenzene cores reveals a difference in the properties of the photochromic moiety upon dendritic incorporation as well as a significant difference in the photomodulation of dendrimer properties. The E --> Z photoisomerization quantum yield decreased markedly with increasing generation for dendrimers 1a-e but only slightly for dendrimers 2a-e. However, increasing generation did not significantly alter thermal isomerization kinetics or activation barriers. The hydrodynamic volumes of azobenzene-containing dendrimers 2b-e were significantly modulated when the azobenzene unit is subjected to irradiation, while those of dendrimers 1b-e were only slightly affected.

7.
Zhonghua Shao Shang Za Zhi ; 18(3): 155-8, 2002 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-12460511

RESUMO

OBJECTIVE: To observe the effects of respiratory support with high frequency jet ventilation (HFJV) in severely burned patients with inhalation injury during early postburn stage. METHODS: Twenty severely burned patients with TBSA of 79.6 +/- 29.3% and inhalation injury were enrolled in the study. Nineteen cases received tracheostomy after admission and only one received nasal intubation. All the patients underwent HFJV to correct hypoxia. The changes in blood gas analysis, respiratory rate and pulse were recorded before and 11 days after the ventilation. RESULTS: Tracheostomy was performed on 2.7 +/- 2.4 postburn days (PBDs), and HFJV was given during 4.4 +/- 2.9 PBDs. PaO(2) was evidently higher during 1 - 3 days after HFJV than that before the ventilation (P < 0.01) and remained at high level for 1 week after HFJV. There was no change in PaCO(2), respiratory rate and pulse during the ventilation. CONCLUSION: HFJV was beneficial in improving oxygenation and without any obvious side effects during the early management of severely burned patients with inhalation injury. This might be an optimal respiratory support pattern.


Assuntos
Queimaduras/complicações , Ventilação em Jatos de Alta Frequência , Lesão por Inalação de Fumaça/terapia , Adulto , Gasometria , Queimaduras/cirurgia , Humanos , Pessoa de Meia-Idade , Lesão por Inalação de Fumaça/etiologia , Lesão por Inalação de Fumaça/cirurgia , Traqueostomia
8.
Gene ; 285(1-2): 149-56, 2002 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-12039041

RESUMO

ras GTPase activating protein (rasGAP) is highly conserved among mammalian species and is required for normal cardiovascular system development. Expression of this protein exhibits both quantitative and qualitative variability among tissues. Using a combination of DNA sequencing and database analyses, we have determined that the human rasGAP gene spans 122 kb and is composed of 25 exons; the size of each intron and the intron/exon junctions also have been elucidated. With one exception, all intron/exon boundaries conform to the GT/AG rule; the splice donor site of intron 3 is GC/AG. Results of RNA ligase mediated rapid amplification of cDNA ends followed by sequence determination indicate that the transcription start point (TSP) is approximately 588 bp upstream from the translational start site and is uninterrupted by introns; this extremely long 5' untranslated region is continuous with the first coding exon. Analysis of 1 kb of sequence upstream of the TSP did not identify any of the typical promoter elements (TATA or CAAT boxes). Sequential deletions of this 1 kb region followed by secreted alkaline phosphatase reporter gene analysis revealed that transcription is supported by this region of the rasGAP gene. Because the highest efficiency is demonstrated by a 213 bp sequence just upstream from the TSP (-786 to -584), this region is identified as containing the rasGAP minimal promoter. Sequence analysis of this 213 bp sequence shows few candidate sites for transcription factor binding. A 406 bp fragment surrounding the TSP exhibits characteristics of a CpG island (68% C+G; observed/expected ratio of CpG=0.95). RapidScan analysis revealed that high levels of rasGAP transcript are present in placenta and testis, but transcript is not detectable in kidney and intestinal tract. These data suggest that rasGAP transcription is regulated by an atypical mechanism capable of producing quantitative variability among tissue types.


Assuntos
Proteínas Ativadoras de ras GTPase/genética , Fosfatase Alcalina/genética , Fosfatase Alcalina/metabolismo , Sequência de Bases , Ilhas de CpG/genética , DNA/química , DNA/genética , Éxons , Feminino , Regulação da Expressão Gênica , Regulação da Expressão Gênica no Desenvolvimento , Genes/genética , Células HeLa , Humanos , Íntrons , Masculino , Dados de Sequência Molecular , Regiões Promotoras Genéticas/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Análise de Sequência de DNA , Sítio de Iniciação de Transcrição , Transfecção
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