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1.
Artigo em Inglês | MEDLINE | ID: mdl-38614873

RESUMO

OBJECTIVE: This study endeavored to develop a novel, fully automated deep-learning model to determine the topographic relationship between mandibular third molar (MM3) roots and the inferior alveolar canal (IAC) using panoramic radiographs (PRs). STUDY DESIGN: A total of 1570 eligible subjects with MM3s who had paired PR and cone beam computed tomography (CBCT) from January 2019 to December 2020 were retrospectively collected and randomly grouped into training (80%), validation (10%), and testing (10%) cohorts. The spatial relationship of MM3/IAC was assessed by CBCT and set as the ground truth. MM3-IACnet, a modified deep learning network based on YOLOv5 (You only look once), was trained to detect MM3/IAC proximity using PR. Its diagnostic performance was further compared with dentists, AlexNet, GoogleNet, VGG-16, ResNet-50, and YOLOv5 in another independent cohort with 100 high-risk MM3 defined as root overlapping with IAC on PR. RESULTS: The MM3-IACnet performed best in predicting the MM3/IAC proximity, as evidenced by the highest accuracy (0.885), precision (0.899), area under the curve value (0.95), and minimal time-spending compared with other models. Moreover, our MM3-IACnet outperformed other models in MM3/IAC risk prediction in high-risk cases. CONCLUSION: MM3-IACnet model can assist clinicians in MM3s risk assessment and treatment planning by detecting MM3/IAC topographic relationship using PR.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Aprendizado Profundo , Dente Serotino , Radiografia Panorâmica , Raiz Dentária , Humanos , Dente Serotino/diagnóstico por imagem , Masculino , Estudos Retrospectivos , Feminino , Tomografia Computadorizada de Feixe Cônico/métodos , Raiz Dentária/diagnóstico por imagem , Adulto , Nervo Mandibular/diagnóstico por imagem , Mandíbula/diagnóstico por imagem , Pessoa de Meia-Idade
2.
Entropy (Basel) ; 24(5)2022 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-35626625

RESUMO

In order to improve the transmission efficiency and security of image encryption, we combined a ZUC stream cipher and chaotic compressed sensing to perform image encryption. The parallel compressed sensing method is adopted to ensure the encryption and decryption efficiency. The ZUC stream cipher is used to sample the one-dimensional chaotic map to reduce the correlation between elements and improve the randomness of the chaotic sequence. The compressed sensing measurement matrix is constructed by using the sampled chaotic sequence to improve the image restoration effect. In order to reduce the block effect after the parallel compressed sensing operation, we also propose a method of a random block of images. Simulation analysis shows that the algorithm demonstrated better encryption and compression performance.

3.
Entropy (Basel) ; 23(5)2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-34066391

RESUMO

The network security transmission of digital images needs to solve the dual security problems of content and appearance. In this paper, a visually secure image compression and encryption scheme is proposed by combining compressed sensing (CS) and regional energy. The plain image is compressed and encrypted into a secret image by CS and zigzag confusion. Then, according to the regional energy, the secret image is embedded into a carrier image to obtain the final visual secure cipher image. A method of hour hand printing (HHP) scrambling is proposed to increase the pixel irrelevance. Regional energy embedding reduce the damage to the visual quality of carrier image, and the different embedding positions between images greatly enhances the security of the encryption algorithm. Furthermore, the hyperchaotic multi-character system (MCS) is utilized to construct measurement matrix and control pixels. Simulation results and security analyses demonstrate the effectiveness, security and robustness of the propose algorithm.

4.
Ying Yong Sheng Tai Xue Bao ; 32(5): 1807-1815, 2021 May.
Artigo em Chinês | MEDLINE | ID: mdl-34042377

RESUMO

To get an optimal mode of irrigation and nitrogen supply for table grape production in North China, a pot experiment was conducted to investigate the effects of different irrigation modes and N application rates on dry matter accumulation and distribution, yield, water use efficiency, and nitrogen use efficiency of table grape. The irrigation modes included conventional drip irrigation (CDI, with sufficient irrigation), alternate partial root-zone drip irrigation (ADI, with 50% amount of the irrigation water of CDI) and fixed partial root-zone drip irrigation (FDI, with 50% amount of the irrigation water of CDI). The nitrogen application rates were set at 0.4 (N1), 0.8 (N2) and 1.2 (N3) g·kg-1 dry soil. The results showed that compared with CDI, ADI and FDI reduced new shoot pruning amount by 34.8% and 11.2%, respectively. New shoot pruning amount increased with increasing N application rates, being highest under CDIN3. Dry matter accumulation of ADI was the highest, being 5.1% and 12.8% higher than CDI and FDI. Dry matter accumulation was higher under N2 and N3 than N1. Compared with CDI and FDI, leaf to fruit ratio reduced but harvest index significantly increased in ADI, while those variables showed no significant difference among diffe-rent N application rates. The ratio of pruning amount to the biomass accumulated in the current year in ADIN2 was the lowest among the treatments. Compared with CDI and FDI, ADI increased grape fruit yield by 6.0% and 10.4%, respectively. Fruit yield was enhanced with increasing nitrogen application rates under the same irrigation condition, with the highest yield under the ADIN2 and ADIN3. Water use efficiency (WUE) increased significantly in ADI compared with CDI and FDI, with the highest value being observed in ADI coupled with N2 or N3. Nitrogen use efficiency (NUE) showed a trend of ADI>CDI>FDI. In addition, NUE decreased with increasing nitrogen supply level across the irrigation modes. In conclusion, ADIN2 could reduce the redundant growth of grape tree, promote the transfer of dry matter to fruit, which increased yield and use efficiency of both water and nitrogen, which is a suitable coupling water and nitrogen supply mode for grape production in northern China.


Assuntos
Nitrogênio , Vitis , Irrigação Agrícola , Biomassa , China , Fertilizantes , Solo , Água/análise
5.
Artigo em Inglês | MEDLINE | ID: mdl-27321874

RESUMO

The nuclear receptor E75 is an early-responsive gene in 20-hydroxyecdysone (20E) signaling pathway, and is found to play essential roles in many aspects of arthropods development. In this study, a cDNA encoding the E75 nuclear receptor of the swimming crab, Portunus trituberculatus was cloned using RT-PCR and RACE. The PtE75 cDNA was 3211bp in length, and encodes a protein of 795 amino acids. The DBD region of the predicted amino acid sequence for PtE75 was highly conserved with other arthropoda E75s, while its LBD region was more similar to decapod E75s. Tissue distribution analysis showed that PtE75 transcript was widespread among tissues and relatively abundant in Y-organ, epidermis, eyestalk, and muscles. PtE75 exhibited tissue-specific expression patterns in these four tissues, which may depend on the distinct action of 20E on different tissues. The expression of PtE75 in Y-organ and epidermis were induced by eyestalk ablation (ESA), indicating its responsiveness to the increasing hemolymph 20E titer. To identify potential targets for ecdysteroid control the in Y-organ, epidermis, and eyestalk, the expression change of an ecdysteroid synthesis gene PtSad in Y-organ, a chitin degradation gene PtChi1 in epidermis, and the molt-inhibiting hormone gene PtMIH in eyestalk were investigated after silencing of PtE75 mRNA. The double stranded RNA (dsRNA) of PtE75 caused a loss in PtChi and PtMIH expression, while an increase in PtSad expression. The results suggested that the ecdysteroids may act through E75, and play a stimulatory role on chitin degradation in epidermis and MIH synthesis in eyestalk, and an negative feedback effect on ecdysteroid synthesis in Y-organ.


Assuntos
Braquiúros/genética , Braquiúros/metabolismo , DNA Complementar/genética , Ecdisteroides/metabolismo , Regulação da Expressão Gênica , Receptores Citoplasmáticos e Nucleares/genética , Transcrição Gênica , Sequência de Aminoácidos , Animais , Sequência de Bases , Braquiúros/crescimento & desenvolvimento , Clonagem Molecular , Estágios do Ciclo de Vida , Especificidade de Órgãos , Interferência de RNA , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Citoplasmáticos e Nucleares/química , Receptores Citoplasmáticos e Nucleares/metabolismo
6.
Anim Reprod Sci ; 168: 40-49, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26952760

RESUMO

Juvenile hormone (JH) and methyl farnesoate (MF) play essential roles in the development and reproduction of insects and crustaceans respectively. Juvenile hormone acid methyltransferase (JHAMT) catalyzes the methyl esterification in insect JH biosynthesis, while the corresponding step in crustacean MF biosynthesis was long thought to be catalyzed by farnesoic acid O-methyltransferase (FAMeT). However, the new discovery of JHAMT orthologs in crustaceans indicates that JHAMT may also play essential role in the MF biosynthesis in crustaceans. Here we cloned and characterized the full-length cDNA encoding JHAMT in the swimming crab Portunus trituberculatus (PtJHAMT). Sequence and structure analysis of PtJHAMT revealed that it was composed of a 6-stranded ß sheet with 9 α helices, and contained a signature Sadenosyl-L-methionine (SAM) binding motif, which is the hallmark in all SAM dependent methyltransferases (SAM-MTs). Several active sites that are critical for the interaction of SAM and JH/FA substrate were also conserved in PtJHAMT. The gene expression of PtJHAMT was highly specific to the mandibular organ, which is the sole site of MF synthesis. PtJHAMT expression significantly increased in the late-vitellogenic stage and mature stage, which suggests a possible role of PtJHAMT in modulating ovarian development. The role of PtJHAMT and PtFAMeT in MF biosynthesis was further investigated by RNA interfering (RNAi). Injection of PtJHAMT and PtFAMeT dsRNA both led to a decrease in hemolymph MF titers. Injection of PtHMGR dsRNA caused the decrease in PtJHAMT expression, but had no effect on mRNA level of PtFAMeT. Together these results suggested that JHAMT and FAMeT are both involved in the MF biosynthesis in crustaceans, while the JHAMT is highly specific to FA substrate, and FAMeT may have more catalytic functions.


Assuntos
Braquiúros/metabolismo , Ácidos Graxos Insaturados/biossíntese , Hormônios de Invertebrado/fisiologia , Metiltransferases/fisiologia , Animais , Braquiúros/crescimento & desenvolvimento , Braquiúros/fisiologia , Clonagem Molecular , Ácidos Graxos Insaturados/análise , Feminino , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Hemolinfa/química , Hormônios de Invertebrado/genética , Metiltransferases/genética , Ovário/crescimento & desenvolvimento , Filogenia
7.
Tumour Biol ; 35(12): 12369-78, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25179844

RESUMO

Epithelial ovarian cancer (EOC) is the leading cause of death from gynecologic malignancies. Platinum-based chemotherapy is the first-line treatment for the advanced ovarian cancer, but resistance to cisplatin remains a major obstacle to successful treatment. MicroRNAs (miRNAs) are a class of non-coding RNAs that play important roles in disease processes, including the development of drug resistance. In this study, we found miR-449a were significantly downregulated in the cisplatin-resistant ovarian cell lines SKOV3/DDP and A2780/DDP, compared with their sensitive parent line SKOV3 and A2780, respectively. The overexpression of miR-449a increased cisplatin sensitivity of SKOV3/DDP and A2780/DDP cells by inhibiting proliferation and promoting apoptosis. The luciferase assay confirmed that miR-449a functioned through suppressing NOTCH1 directly. Concordantly, BALB/c nude mice that were injected intraperitoneally with SKOV3/DDP cells transfected with miR-449a mimics exhibited enhanced cisplatin sensitivity in vivo. Taken together, these results suggest that the ectopic expression of miR-449a may be a promising therapeutic strategy for the management of cisplatin resistance in ovarian cancer.


Assuntos
Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Ovarianas/genética , Interferência de RNA , Receptor Notch1/genética , Animais , Apoptose/efeitos dos fármacos , Apoptose/genética , Sequência de Bases , Sítios de Ligação , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/genética , Cisplatino/farmacologia , Modelos Animais de Doenças , Regulação para Baixo , Feminino , Humanos , Camundongos , MicroRNAs/química , Neoplasias Ovarianas/patologia , Receptor Notch1/química , Ensaios Antitumorais Modelo de Xenoenxerto
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