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1.
Opt Lett ; 49(5): 1285-1288, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38426994

RESUMO

We report and fabricate a novel, to our knowledge, vortex beam generator called elliptical spiral zone plate (ESZP) using direct laser writing (DLW), which can generate the elliptical perfect vortex beam (EPVB). It is shown that the radius of the EPVB can be adjusted by tuning the control parameters of the ESZP. It is verified through the interference experiment and the Hermitian-Gaussian light field that the topological charge of the EPVB is consistent with the design. In addition, we integrate the ESZP at the tip of the single-mode fiber. Our work may set the scene for applications in fiber optical tweezers, optical communications, and integrated optics.

2.
Opt Lett ; 49(17): 4914-4917, 2024 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-39207996

RESUMO

We propose a complex-amplitude diffractive processor based on diffractive deep neural networks (D2NNs). By precisely controlling the propagation of an optical field, it can effectively remove the motion blur in numeral images and realize the restoration. Comparative analysis of phase-only, amplitude-only, and complex-amplitude diffractive processor reveals that the complex-amplitude network significantly enhances the performance of the processor and improves the peak signal-to-noise ratio (PSNR) of the images. Appropriate use of complex-amplitude networks contributes to reduce the number of network layers and alleviates alignment difficulties. Due to its fast processing speed and low power consumption, complex-amplitude diffractive processors hold potential applications in various fields including road monitoring, sports photography, satellite imaging, and medical diagnostics.

3.
Opt Lett ; 49(11): 3259-3262, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824378

RESUMO

Fiber optical tweezers (FOTs) provide a functionality for micro-/nanoparticle manipulation with a slim and flexible optical fiber setup. An added in situ spectroscopic functionality can achieve characterization of the trapped particle, potentially useful for endoscopic, in-vivo studies in an inherently heterogeneous environment if the applicator end is all-fiber-built. Here, we demonstrate all-fiber optical tweezers (a-FOTs) for the trapping and in situ spectral measurement of a single, cell-sized microparticle. The key to ensure the simultaneous bifunctionality is a high numerical aperture (NA) Fresnel lens fabricated by two-photon direct laser writing (DLW) corrected by grid-correction methods. We demonstrate trapping and time-resolved, in situ spectroscopy of a single upconversion particle (UCP), a common fluorescent biomarker in biophotonics. The system achieves a 0.5-s time resolution in the in situ spectral measurement of a trapped UCP. The all-fiber designed system preserves the advantages of flexibility and robustness of the fiber, potentially useful for in-vivo biomedical studies such as cell-to-cell interactions, pH and temperature detection, and nucleic acids detection.

4.
Opt Lett ; 48(20): 5379-5382, 2023 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-37831872

RESUMO

We use a flexible two-photon photopolymerization direct laser writing to fabricate an integrated diffractive lens system on a fiber tip to expand the output beam of the fiber. The results show that the micro-integrated beam expander based on double lenses (axial size of about 100 µm) has a magnification of 5.9 and a loss of 0.062 dB. Subsequently, we demonstrate the fabrication of a spiral phase plate (diffractive optical elements) and micro-lens arrays (refractive optical elements) on an integrated beam expander, and their optical properties are measured and analyzed, respectively. This Letter is an exploration of the future integrated micro-optical systems on an optical fiber tip.

5.
J Environ Manage ; 336: 117710, 2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-36921471

RESUMO

Nitrogen, as a common element, is widely present in biomass. The effects of nitrogenous substances on the same origin pyrolysis of biomass and the consequences of N-containing biochar on the catalytic process of volatiles are important for further analyzing the pyrolysis mechanism of biomass. In this research, N-containing biochar was prepared under different conditions, and the interaction between N-containing biochar and biomass pyrolysis volatiles at 400-700 °C was studied. The results show that N-containing biochar can simultaneously participate in reactions as adsorbents, catalysts, and reactants. Its catalytic effect is obviously different for various N configurations. Pyridinic N and pyrrolic N can promote the cracking of lignin into methoxy phenol compounds and promote the further cracking of 5-hydroxymethylfurfural. Graphitic N and oxidized N can promote the further decomposition of phenol and the conversion of D-xylose into small-molecule ketones. In addition, oxidized N can also inhibit the cracking of lignin to produce guaiacol. In the long-term interaction, the highly active pyridinic N tends to convert to a more stable graphitic N.


Assuntos
Lignina , Pirólise , Fenóis , Nitrogênio , Carvão Vegetal , Biomassa
6.
Arch Virol ; 167(9): 1893-1897, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35668128

RESUMO

Here, a novel mycovirus, tentatively designated as "Botryosphaeria dothidea fusarivirus 2" (BdFV2), was discovered in Botryosphaeria dothidea strain JZ-3. The complete genome sequence is 6,271 nucleotides (nt) in length, excluding the poly(A) tail, and contains two putative open reading frames (ORFs). The larger ORF1 encodes a polypeptide of 1,552 amino acids (aa) with conserved RNA-dependent RNA polymerase (RdRp) domains and a viral helicase domain. The ORF1-encoded polypeptide shares 19.47-78.70% sequence identity with those of other fusariviruses and shares the highest sequence identity (78.70%) with the corresponding protein aa sequences of Neofusicoccum luteum fusarivirus 1 (NlFV1) isolate CBS110299. The small ORF2 encodes a hypothetical protein with 479 aa, which is predicted to contain a chromosome segregation protein SMC domain of unknown function. Sequence alignments and phylogenetic analysis indicated that BdFV2 is a distinct member of the recently established family Fusariviridae. BdFV2 appears to be a novel fusarivirus infecting a pathogenic B. dothidea strain that causes pear ring rot disease.


Assuntos
Micovírus , Pyrus , Vírus de RNA , Ascomicetos , Genoma Viral , Fases de Leitura Aberta , Filogenia , RNA Viral/genética
7.
J Environ Manage ; 318: 115555, 2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-35738129

RESUMO

Graphite is a widely used industrial material, which experienced a marked shortage caused by the growing demand for electrode anode material and the increased costs for raw material. Graphitic carbon from biomass is a promising approach that will result in low-cost and efficient preparation. Herein, Fe(NO3)3 was selected as the catalyst for pine sawdust, and the effects of temperature and iron content on the graphitization of biochar were investigated. Additionally, the formation mechanism of the graphitic crystallite structure was explored. Results showed that the formation of pyrolysis gas increased with the increase in the amount of catalyst added or pyrolysis temperature. The change in pyrolysis gas, such as H2 and CO, was a critical auxiliary factor reflecting the conversion process. As temperature was increased from 600 °C to 800 °C, the solid products showed high graphitization and low solid yield. Graphite structure mainly formed at 700 °C because of the formation of Fe nanoparticles. The increase in the amount of catalyst could provide more reaction sites and promote the contact between Fe and C, showing that amorphous carbon is dissolved on Fe nanoparticles and precipitated into ordered graphitic carbon. On this basis, a mechanism of "carbon dissolution-precipitation" was proposed to explain the formation of graphite structure, and the whole pyrolysis process included the transformation of the iron element were analyzed.


Assuntos
Grafite , Biomassa , Carbono/química , Catálise , Grafite/química , Ferro/química , Nitratos , Óxidos de Nitrogênio , Temperatura
8.
BMC Musculoskelet Disord ; 21(1): 379, 2020 Jun 13.
Artigo em Inglês | MEDLINE | ID: mdl-32534573

RESUMO

BACKGROUND: An autologous bone-cage made from the spinous process and laminae might provide a stability in posterior lumbar interbody fusion (PLIF) close that of the traditional-cage made of polyetheretherketone (PEEK) or titanium. The biomechanical effect of autologous bone-cages on cage stability, stress, and strains, and on the facet contact force has not been fully described. This study aimed to verify whether autologous bone-cages can achieve similar performance as that of PEEK cages in PLIF by using a finite element analysis. METHODS: The finite element models of PLIF with an autologous bone-cage, a titanium cage, and a PEEK cage were constructed. The autologous bone-cage was compared with the titanium and PEEK cages. The mechanical properties of the autologous bone-cage were obtained through mechanical tests. The four motion modes were simulated. The range of motion (ROM), the stress in the cage-end plate interface, and the facet joint force (FJF) were compared. RESULTS: The ROM was increased at adjacent levels but decreased over 97% at the treated levels, and the intradiscal pressure at adjacent levels was increased under all conditions in all models. The FJF disappeared at treated levels and increased under extension, lateral bending, and lateral rotation in all models. The maximum stress of the cage-endplate interface was much lower in the autologous bone-cage model than those in the PEEK and titanium cage models. CONCLUSIONS: In a finite model of PLIF, the autologous bone-cage model could achieve stability close that of traditional titanium or PEEK cages, reducing the risk of subsidence.


Assuntos
Fenômenos Biomecânicos , Fixadores Internos , Vértebras Lombares/cirurgia , Fusão Vertebral/instrumentação , Adulto , Benzofenonas , Materiais Biocompatíveis , Análise de Elementos Finitos , Humanos , Cetonas/química , Masculino , Modelos Anatômicos , Polietilenoglicóis/química , Polímeros , Porosidade , Amplitude de Movimento Articular , Estresse Mecânico , Titânio , Articulação Zigapofisária/fisiopatologia
9.
Molecules ; 24(13)2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31269719

RESUMO

Gastrodia elata Blume (G. elata) is a valuable Traditional Chinese Medicine (TCM) with a wide range of clinical applications. G. elata polysaccharides, as one of the main active ingredients of G. elata, have interesting extraction, purification, qualitative analysis, quantitative analysis, derivatization, and pharmacological activity aspects, yet a review of G. elata polysaccharides has not yet been published. Based on this, this article summarizes the progress of G. elata polysaccharides in terms of the above aspects to provide a basis for their further research and development.


Assuntos
Gastrodia/química , Polissacarídeos/análise , Polissacarídeos/farmacologia , Antineoplásicos/farmacologia , Peso Molecular , Fármacos Neuroprotetores/farmacologia , Polissacarídeos/isolamento & purificação
10.
Clin Orthop Relat Res ; 475(8): 2095-2104, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28425055

RESUMO

BACKGROUND: Joint salvage surgery for patients with juxtaarticular osteosarcoma remains challenging, especially when the tumor invades the epiphysis. Because patients are surviving longer with current chemotherapy regimens, it is advantageous to retain native joints if possible, especially in young patients. However, the results using joint-preserving tumor resections in this context have not been well characterized. QUESTIONS/PURPOSES: (1) What are the functional outcomes after limb salvage surgery at a minimum of 3 years? (2) What are the oncologic outcomes? (3) Is joint salvage surgery for epiphyseal tumors associated with an increased risk of local recurrence compared with metaphyseal tumors not invading the epiphysis? (4) What are the complications associated with joint salvage surgery? METHODS: Between 2004 and 2013, we treated 117 patients with juxtaarticular osteosarcoma; of those, 43 (38%) were treated with joint salvage surgery, and 41 (95%) of the 43 patients are included in our study. The other two (5%) were lost to followup before 3 years (mean, 4.4 years; range, 3-11 years,). During the period in question, we generally performed joint salvage surgery in these patients when they had a favorable response to chemotherapy, did not have a pathologic fracture or extrusion of the tumor into the joint, and did not have a whole-epiphyseal osteolytic lesion, a large mass, or obvious neurovascular involvement. This report is a followup of an earlier study; the current study includes an additional nine patients, and additional followup of a mean of 19 months for the patients included in the earlier report. We ascertained overall survival and survival free from local recurrence which was estimated using the Kaplan-Meier method, functional status of the limb which was evaluated using the Musculoskeletal Tumor Society (MSTS)-93 scoring system, and recorded reconstructive complications including infection, fracture, skin necrosis, and nonunion. We compared oncologic and functional outcomes between patients with (n = 28) and without tumor extension to epiphysis (n =13). We also compared oncologic and functional outcomes among patients with different adjuvant treatments including microwave ablation (n = 11), cryoablation (n = 12), and navigation-assisted osteotomy (n = 5). Complications were tallied using records from our institutional database. RESULTS: The overall Kaplan-Mayer survival rate was 82% (95% CI, 104-128 months) at 5 years. The overall Kaplan-Meier survivorship from local recurrence was 91% at 5 years (95% CI, 115-133 months). Three patients had a local recurrence, but none had local recurrence in or close to the remaining epiphysis. The MSTS scores ranged from 22 to 30 points, with a median of 28. There were no differences in survival rate, local recurrence, or MSTS scores between patients with a tumor that did not invade the epiphysis and those in whom the tumor did invade the epiphysis. There were differences in MSTS scores among patients with epiphyseal tumor extension in which different adjuvant techniques, including microwave ablation, cryoablation, and navigation-assisted osteotomy, were used. Additional surgical procedures were recorded for 10 patients (24%). Osteonecrosis of the residual epiphysis was detected 13 patients (31%). CONCLUSIONS: Our findings suggest it is possible to salvage joints in selected patients with juxtaarticular osteosarcoma around the knee. The patients who have a favorable response to chemotherapy are the best candidates for this approach. Future studies might explore the role of adjuvant techniques of microwave ablation and cryoablation, particularly when the tumor invades the epiphysis, and whether resections can be facilitated with navigation. LEVEL OF EVIDENCE: Level IV, therapeutic study.


Assuntos
Neoplasias Ósseas/cirurgia , Artropatias/cirurgia , Osteossarcoma Justacortical/cirurgia , Osteotomia/métodos , Terapia de Salvação/métodos , Neoplasias Ósseas/fisiopatologia , Criança , Pré-Escolar , Epífises/cirurgia , Feminino , Seguimentos , Humanos , Artropatias/fisiopatologia , Joelho/cirurgia , Salvamento de Membro/métodos , Masculino , Osteossarcoma Justacortical/fisiopatologia , Procedimentos de Cirurgia Plástica/métodos , Estudos Retrospectivos , Resultado do Tratamento
11.
Tumour Biol ; 36(4): 2427-35, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25431261

RESUMO

The study aims to identify novel gene mutations in osteosarcoma and to guide individualized preoperative chemotherapy for osteosarcoma based on the analysis of expression and mutations of the drug-metabolism-related genes. Twenty-eight osteosarcoma patients received individualized preoperative chemotherapy regimens. Expression levels and mutations of chemotherapy-related genes in samples collected from the patients were determined using real-time PCR and DNA sequencing, respectively. Patient sensitivity to chemotherapeutic agents was evaluated by systematic analysis of the PCR and sequencing results. Novel mutations were identified via high-throughput sequencing of 339 genes in 10 osteosarcoma samples. Individualized preoperative chemotherapy outcomes were valid for nine patients (n = 9/28, 32.1%). Chemosensitivity assays showed that all 28 patients were sensitive to ifosfamide, whereas 46.4 and 39.2% were sensitive to docetaxel and platinum, respectively. More importantly, patients receiving highly chemosensitive chemotherapy agents had better prognosis and treatment outcomes than those receiving less chemosensitive agents (P < 0.05). In addition, 39 gene mutations were detected in at least five osteosarcoma tumor samples. Analysis of the expression and mutation of drug-metabolism-related genes will aid in the design of effective individualized preoperative chemotherapy regimens for osteosarcoma. Determining the chemosensitivity of individual tumors to chemotherapeutic agents will facilitate the development of better therapeutic approaches. Individualized treatment of osteosarcoma may improve chemotherapy efficacy and the survival rate of osteosarcoma patients. High-throughput genotyping allows mapping of osteosarcoma mutations, and novel gene mutations offered new candidates for diagnosis and therapeutic targeting.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Neoplasias Ósseas/tratamento farmacológico , Osteossarcoma/tratamento farmacológico , Medicina de Precisão , Prognóstico , Adolescente , Adulto , Neoplasias Ósseas/genética , Docetaxel , Feminino , Regulação Neoplásica da Expressão Gênica , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Proteínas de Neoplasias/biossíntese , Proteínas de Neoplasias/genética , Osteossarcoma/genética , Osteossarcoma/patologia , Taxoides/administração & dosagem , Resultado do Tratamento
12.
Biotechnol J ; 19(9): e2400309, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39295562

RESUMO

The filamentous fungus Rhizopus oryzae is one of the main industrial strains for the production of a series of important chemicals such as ethanol, lactic acid, and fumaric acid. However, the lack of efficient gene editing tools suitable for R. oryzae makes it difficult to apply technical methods such as metabolic engineering regulation and synthetic biology modification. A CRISPR-Cas9 system suitable for efficient genome editing in R. oryzae was developed. Firstly, four endogenous U6 promoters of R. oryzae were identified and screened with the highest transcriptional activity for application to sgRNA transcription. It was then determined that the U6 promoter mediated CRISPR/Cas9 system has the ability to efficiently edit the genome of R. oryzae through NHEJ and HDR-mediated events. Furthermore, the newly constructed CRISPR-Cas9 dual sgRNAs system can simultaneously disrupt or insert different fragments of the R. oryzae genome. Finally, this CRISPR-Cas9 system was applied to the genome editing of R. oryzae by knocking out pyruvate carboxylase gene (PYC) and pyruvate decarboxylase gene (pdcA) and knocking in phosphofructokinase (pfkB) from Escherichia coli and L-lactate dehydrogenase (L-LDH) from Heyndrickxia coagulans, which resulted in a substantial increase in L-LA production. In summary, this study showed that the CRISPR/Cas9-based genome editing tool is efficient for manipulating genes in R. oryzae.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Ácido Láctico , Engenharia Metabólica , Rhizopus oryzae , Sistemas CRISPR-Cas/genética , Edição de Genes/métodos , Ácido Láctico/metabolismo , Engenharia Metabólica/métodos , Rhizopus oryzae/genética , L-Lactato Desidrogenase/genética , L-Lactato Desidrogenase/metabolismo , Genoma Fúngico/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Piruvato Descarboxilase/genética , Piruvato Descarboxilase/metabolismo , Rhizopus/genética
13.
Adv Sci (Weinh) ; 11(6): e2307693, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38152952

RESUMO

Flexible tactile sensors with multifunctional sensing functions have attracted much attention due to their wide applications in artificial limbs, intelligent robots, human-machine interfaces, and health monitoring devices. Here, a multifunctional flexible tactile sensor based on resistive effect for simultaneous sensing of pressure and temperature is reported. The sensor features a simple design with patterned metal film on a soft substrate with cavities and protrusions. The decoupling of pressure and temperature sensing is achieved by the reasonable arrangement of metal layers in the patterned metal film. Systematically experimental and numerical studies are carried out to reveal the multifunctional sensing mechanism and show that the proposed sensor exhibits good linearity, fast response, high stability, good mechanical flexibility, and good microfabrication compatibility. Demonstrations of the multifunctional flexible tactile sensor to monitor touch, breathing, pulse and objects grabbing/releasing in various application scenarios involving coupled temperature/pressure stimuli illustrate its excellent capability of measuring pressure and temperature simultaneously. These results offer an effective tool for multifunctional sensing of pressure and temperature and create engineering opportunities for applications of wearable health monitoring and human-machine interfaces.

14.
J Chromatogr A ; 1715: 464613, 2024 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-38184988

RESUMO

Ultra-high-performance liquid chromatography-mass spectrometry (UHPLC-MS) technology has emerged as a crucial tool for identifying components in traditional Chinese medicine (TCM). However, the characterization of the chemical profiles of TCM prescriptions (TCMPs) which often consist of multiple herbal medicines and contain diverse structural types, presents several challenges, such as component overlapping and time-consuming. In this study, a novel strategy known as the multi-module structure labelled molecular network (MSLMN), which integrates molecular networking, database annotation, and cluster analysis techniques, has been successfully proposed, which facilitates the identification of chemical constituents by leveraging a high-structural similarity ion list derived from the MSLMN. It has been effectively applied to analyze the chemical profile of Xiaoyao San (XYS), a classical TCMP. Through the MSLMN method, a total of 302 chemical constituents were identified, covering nine structural types in XYS. Furthermore, a validated and quantitative analytical method using UHPLC-QqQ-MS/MS technology was developed for 31 identified chemicals, encompassing all eight herbal medicines present in XYS, and the developed analytical approach was applied to investigate the content distribution across 40 different batches of commercially available XYS. In total, the proposed strategy has practical significance for improving the insight into the chemical profile of XYS and serves as a valuable approach for handling complex system data based on UHPLC-MS, particularly for TCMPs.


Assuntos
Medicamentos de Ervas Chinesas , Plantas Medicinais , Medicina Tradicional Chinesa , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Medicamentos de Ervas Chinesas/química
15.
Cells ; 12(19)2023 09 29.
Artigo em Inglês | MEDLINE | ID: mdl-37830600

RESUMO

Pear ring rot disease is an important branch disease, caused by Botryosphaeria dothidea. With the discovery of fungal viruses, the use of their attenuated properties for biological control provides a new strategy for the biological control of fungal disease. RNA silencing is a major antiviral defense mechanism in plants, insects, and fungi. Viruses encode and utilize RNA silencing suppressors to suppress host defenses. Previous studies revealed that Botryosphaeria dothidea chrysovirus 1 (BdCV1) exhibited weak pathogenicity and could activate host gene silencing by infecting B. dothidea. The aim of our study was to investigate whether BdCV1 can encode a silencing suppressor and what effect it has on the host. In this study, the capability of silencing inhibitory activity of four BdCV1-encoded proteins was analyzed, and the P3 protein was identified as a BdCV1 RNA silencing suppressor in the exotic host Nicotiana benthamiana line 16c. In addition, we demonstrated that P3 could inhibit local silencing, block systemic RNA silencing, and induce the necrosis reaction of tobacco leaves. Furthermore, overexpression of P3 could slow down the growth rate and reduce the pathogenicity of B. dothidea, and to some extent affect the expression level of RNA silencing components and virus-derived siRNAs (vsiRNAs). Combined with transcriptomic analysis, P3 had an effect on the gene expression and biological process of B. dothidea. The obtained results provide new theoretical information for further study of interaction between BdCV1 P3 as a potential silencing suppressor and B. dothidea.


Assuntos
Ascomicetos , Pyrus , Vírus de RNA , Doenças das Plantas/microbiologia
16.
PLoS One ; 18(11): e0294865, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38019827

RESUMO

In the context of intelligent driving, pedestrian detection faces challenges related to low accuracy in target recognition and positioning. To address this issue, a pedestrian detection algorithm is proposed that integrates a large kernel attention mechanism with the YOLOV5 lightweight model. The algorithm aims to enhance long-term attention and dependence during image processing by fusing the large kernel attention module with the C3 module. Furthermore, it addresses the lack of long-distance relationship information in channel and spatial feature extraction and representation by introducing the Coordinate Attention mechanism. This mechanism effectively extracts local information and focused location details, thereby improving detection accuracy. To improve the positioning accuracy of obscured targets, the alpha CIOU bounding box regression loss function is employed. It helps mitigate the impact of occlusions and enhances the algorithm's ability to precisely localize pedestrians. To evaluate the effectiveness of trained model, experiments are conducted on the BDD100K pedestrian dataset as well as the Pascal VOC dataset. Experimental results demonstrate that the improved attention fusion YOLOV5 lightweight model achieves an average accuracy of 60.3%. Specifically, the detection accuracy improves by 1.1% compared to the original YOLOV5 algorithm, and the accuracy performance index reaches 73.0%. These findings strongly indicate the proposed algorithm in significantly enhancing the accuracy of pedestrian detection in road scenes.


Assuntos
Pedestres , Humanos , Algoritmos , Processamento de Imagem Assistida por Computador , Inteligência , Reconhecimento Psicológico
17.
Mol Plant Pathol ; 24(9): 1107-1125, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37312259

RESUMO

Diseases caused by Alternaria alternata and Botryosphaeria dothidea diminish pear yield and quality, and restrict the pear agricultural industry. Lignification is a conserved mechanism for plant resistance against pathogen invasion. The regulatory mechanisms underlying defence-induced lignification in pear in response to fungal pathogen infection remain unknown. In this study, analysis of lignification level and lignin content in pear revealed that A. alternata and B. dothidea induced lignification, and transcriptomics showed that lignin biosynthesis was affected. To explore whether laccases (LACs) mediated by miR397 regulate lignification in pear, we investigated the role of PcmiR397 in repressing the expression of PcLACs using 5'-RNA ligase-mediated-RACE and co-transformation in tobacco. Opposite expression patterns for PcmiR397 and PcLAC target genes were observed in pear in response to pathogens. Transient transformation in pear demonstrated that silencing PcmiR397 and overexpressing a single PcLAC enhanced resistance to pathogens via lignin synthesis. To further reveal the mechanism underpinning the PcMIR397 response of pear to pathogens, the PcMIR397 promoter was analysed, and pMIR397-1039 was found to be inhibited by pathogen infection. The transcription factor PcMYB44 was up-regulated, and it bound to the PcMIR397 promoter and inhibited transcription following pathogen infection. The results demonstrate the role of PcmiR397-PcLACs in broad-spectrum resistance to fungal disease, and the potential role of PcMYB44 involved in the miR397-PcLAC module in regulating defence-induced lignification. The findings provide valuable candidate gene resources and guidance for molecular breeding to improve resistance to fungal disease in pear.


Assuntos
Pyrus , Pyrus/genética , Pyrus/microbiologia , Lignina/metabolismo , Proteínas de Plantas/metabolismo , Regulação da Expressão Gênica de Plantas , Perfilação da Expressão Gênica , Resistência à Doença/genética
18.
Life Sci ; 333: 122145, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37797685

RESUMO

Colorectal cancer (CRC) is a lethal malignancy with limited treatment strategies. Accumulating evidence indicates that CRC tumorigenesis, progression and metastasis are intimately associated with circadian clock, an inherent 24-h cycle oscillation of biochemical, physiological functions in almost every eukaryote. In the present review, we summarize the altered expression level of circadian genes in CRC and the prognosis associated with gene abundance switch. We illustrate the function and potential mechanisms of circadian genes in CRC pathogenesis and progression. Moreover, circadian based-therapeutic strategies including chronotherapy, therapeutics targeting potential circadian components, and melatonin treatment in CRC are also highlighted.


Assuntos
Relógios Circadianos , Neoplasias Colorretais , Humanos , Relógios Circadianos/genética , Carcinogênese , Neoplasias Colorretais/tratamento farmacológico , Neoplasias Colorretais/genética , Ritmo Circadiano/genética
19.
J Chromatogr A ; 1702: 464045, 2023 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-37236139

RESUMO

Component overlapping and long-time consumption hinder the data processing of offline two-dimensional liquid chromatography mass spectrometry (offline 2D-LC MS) system. Although molecular networking has been commonly employed in data processing of liquid chromatography mass spectrometry (LC-MS), its application in offline 2D-LC MS is challenged by voluminous and redundant data. In light of this, for the first time, a data deduplication and visualization strategy combining hand-in-hand alignment with targeted molecular networking (TMN) for compounds annotation of offline 2D-LC MS data was developed and applied to the chemical profile of Yupingfeng (YPF), a classical traditional Chinese medicine (TCM) prescription, as a case study. Firstly, an offline 2D-LC MS system was constructed for the separation and data acquisition of YPF extract. Then the data of 12 fractions derived from YPF were deconvoluted and aligned as a whole data file by hand-in-hand alignment, resulting in a 49.2% reduction in component overlapping (from 17951 to 9112 ions) and an improvement in the MS2 spectrum quality of precursor ions. Subsequently, the MS2-similarity adjacency matrix of focused parent ions was computed by a self-building Python script, which realized the construction of an innovative TMN. Interestingly, the TMN was found to be able to efficiently distinguish and visualize the co-elution, in-source fragmentations and multi-type adduct ions in a clustering network. Consequently, a total of 497 compounds were successfully identified depending on only seven TMN analysis guided by product ions filtering (PIF) and neutral loss filtering (NLF) for the targeted compounds in YPF. This integrated strategy improved the efficiency of targeted compound discovery in offline 2D-LC MS data, also shown a huge scalability in accurate compound annotation of complex samples. In conclusion, our study developed available concepts and tools while providing a research paradigm for efficient and rapid compound annotation in complex samples such as TCM prescriptions, with YPF as an example.


Assuntos
Medicamentos de Ervas Chinesas , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida/métodos , Espectrometria de Massas , Medicamentos de Ervas Chinesas/química
20.
Biosens Bioelectron ; 224: 115061, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36634509

RESUMO

The intrinsic biophysical properties of cells, such as mechanical, acoustic, and electrical properties, are valuable indicators of a cell's function and state. However, traditional single-cell biophysical characterization methods are hindered by limited measurable properties, time-consuming procedures, and complex system setups. This study presents acousto-dielectric tweezers that leverage the balance between controllable acoustophoretic and dielectrophoretic forces applied on cells through surface acoustic waves and alternating current electric fields, respectively. Particularly, the balanced acoustophoretic and dielectrophoretic forces can trap cells at equilibrium positions independent of the cell size to differentiate between various cell-intrinsic mechanical, acoustic, and electrical properties. Experimental results show our mechanism has the potential for applications in single-cell analysis, size-insensitive cell separation, and cell phenotyping, which are all primarily based on cells' intrinsic biophysical properties. Our results also show the measured equilibrium position of a cell can inversely determine multiple biophysical properties, including membrane capacitance, cytoplasm conductivity, and acoustic contrast factor. With these features, our acousto-dielectric tweezing mechanism is a valuable addition to the resources available for biophysical property-based biological and medical research.


Assuntos
Técnicas Biossensoriais , Som , Citoplasma , Condutividade Elétrica , Acústica
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