Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 54
Filtrar
1.
J Nanobiotechnology ; 22(1): 274, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38773614

RESUMO

Small extracellular vesicle-derived microRNAs (sEV-miRNAs) have emerged as promising noninvasive biomarkers for early cancer diagnosis. Herein, we developed a molecular probe based on three-dimensional (3D) multiarmed DNA tetrahedral jumpers (mDNA-Js)-assisted DNAzyme activated by Na+, combined with a disposable paper-based electrode modified with a Zr-MOF-rGO-Au NP nanocomplex (ZrGA) to fabricate a novel biosensor for sEV-miRNAs Assay. Zr-MOF tightly wrapped by rGO was prepared via a one-step method, and it effectively aids electron transfer and maximizes the effective reaction area. In addition, the mechanically rigid, and nanoscale-addressable mDNA-Js assembled from the bottom up ensure the distance and orientation between fixed biological probes as well as avoid probe entanglement, considerably improving the efficiency of molecular hybridization. The fabricated bioplatform achieved the sensitive detection of sEV-miR-21 with a detection limit of 34.6 aM and a dynamic range from100 aM to 0.2 µM. In clinical blood sample tests, the proposed bioplatform showed results highly consistent with those of qRT-PCRs and the signal increased proportionally with the NSCLC staging. The proposed biosensor with a portable wireless USB-type analyzer is promising for the fast, easy, low-cost, and highly sensitive detection of various nucleic acids and their mutation derivatives, making it ideal for POC biosensing.


Assuntos
Técnicas Biossensoriais , Vesículas Extracelulares , Limite de Detecção , Estruturas Metalorgânicas , MicroRNAs , Papel , Estruturas Metalorgânicas/química , Vesículas Extracelulares/química , Humanos , Técnicas Biossensoriais/métodos , DNA Catalítico/química , Grafite/química , Ouro/química , DNA/química , Nanopartículas Metálicas/química , Hibridização de Ácido Nucleico , Técnicas Eletroquímicas/métodos , Eletrodos , Zircônio/química
2.
Brief Bioinform ; 22(3)2021 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-34020539

RESUMO

With the development of single-cell RNA sequencing (scRNA-seq) technology, it has become possible to perform large-scale transcript profiling for tens of thousands of cells in a single experiment. Many analysis pipelines have been developed for data generated from different high-throughput scRNA-seq platforms, bringing a new challenge to users to choose a proper workflow that is efficient, robust and reliable for a specific sequencing platform. Moreover, as the amount of public scRNA-seq data has increased rapidly, integrated analysis of scRNA-seq data from different sources has become increasingly popular. However, it remains unclear whether such integrated analysis would be biassed if the data were processed by different upstream pipelines. In this study, we encapsulated seven existing high-throughput scRNA-seq data processing pipelines with Nextflow, a general integrative workflow management framework, and evaluated their performance in terms of running time, computational resource consumption and data analysis consistency using eight public datasets generated from five different high-throughput scRNA-seq platforms. Our work provides a useful guideline for the selection of scRNA-seq data processing pipelines based on their performance on different real datasets. In addition, these guidelines can serve as a performance evaluation framework for future developments in high-throughput scRNA-seq data processing.


Assuntos
Algoritmos , Bases de Dados de Ácidos Nucleicos , RNA-Seq , RNA , Análise de Célula Única , Células 3T3 , Animais , Células HEK293 , Humanos , Camundongos , RNA/biossíntese , RNA/genética
3.
Bioinformatics ; 38(8): 2178-2186, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35157021

RESUMO

MOTIVATION: Advanced deep learning techniques have been widely applied in disease diagnosis and prognosis with clinical omics, especially gene expression data. In the regulation of biological processes and disease progression, genes often work interactively rather than individually. Therefore, investigating gene association information and co-functional gene modules can facilitate disease state prediction. RESULTS: To explore the gene modules and inter-gene relational information contained in the omics data, we propose a novel multi-level attention graph neural network (MLA-GNN) for disease diagnosis and prognosis. Specifically, we format omics data into co-expression graphs via weighted correlation network analysis, and then construct multi-level graph features, finally fuse them through a well-designed multi-level graph feature fully fusion module to conduct predictions. For model interpretation, a novel full-gradient graph saliency mechanism is developed to identify the disease-relevant genes. MLA-GNN achieves state-of-the-art performance on transcriptomic data from TCGA-LGG/TCGA-GBM and proteomic data from coronavirus disease 2019 (COVID-19)/non-COVID-19 patient sera. More importantly, the relevant genes selected by our model are interpretable and are consistent with the clinical understanding. AVAILABILITYAND IMPLEMENTATION: The codes are available at https://github.com/TencentAILabHealthcare/MLA-GNN.


Assuntos
COVID-19 , Redes Reguladoras de Genes , Humanos , Proteômica , Redes Neurais de Computação , Perfilação da Expressão Gênica , Teste para COVID-19
4.
J Nat Prod ; 86(7): 1736-1745, 2023 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-37436927

RESUMO

In our ongoing study of fungal bioactive natural products, 12 previously undescribed triquinane sesquiterpene glycosides, namely, antrodizonatins A-L (1-12), and four known compounds (13-16) have been obtained from the fermentation of the basidiomycete Antrodiella zonata. The structures were established unambiguously via extensive spectroscopic analysis and theoretical calculations of electronic circular dichroism spectra. This is the first report of triquinane sesquiterpene glycosides. Compounds 1, 5, and 12 displayed antibacterial activity against Staphylococcus aureus with MIC50 values of 35, 34, and 69 µM, respectively.


Assuntos
Basidiomycota , Polyporales , Sesquiterpenos , Glicosídeos/farmacologia , Glicosídeos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Basidiomycota/química , Estrutura Molecular
5.
Anal Chem ; 94(45): 15887-15895, 2022 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-36325814

RESUMO

tRNA-derived small RNA (tsRNA) has emerged as a new biomarker for early diagnosis and prognosis prediction of breast cancer. Like the detection of other small non-coding RNAs, the traditional DNA circuit could be used for the tsRNA detection. However, the highly coupling DNA strands in the circuit increase the difficulty of design and could raise a false-positive signal. Here, we demonstrated a versatile modularized enzymatic tandem reaction, namely, reverse-transcribed nicking exponential truncation (RT-NExT). This enzymatic reaction was constructed by cohesive modules, which can work independently or in assembly. Each module could amplify and initiate the downstream module. The RT-NExT reaction could detect 10-18 M ts-66 or ts-86 within 10 min and exhibited excellent consistency to the qRT-PCR when measuring the tsRNA expression level of breast cancer or healthy patients. RT-NExT provides an appealing detection strategy for further research on the clinical diagnosis with tsRNAs.


Assuntos
Neoplasias da Mama , MicroRNAs , Pequeno RNA não Traduzido , Humanos , Feminino , RNA de Transferência/metabolismo , MicroRNAs/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética
6.
Bioinformatics ; 37(2): 265-267, 2021 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-33416868

RESUMO

SUMMARY: Currently, various software tools are used to support two mainstream workflows for data-independent acquisition (DIA) mass spectrometry (MS) data processing, namely, spectrum-centric scoring (SCS) and peptide-centric scoring (PCS). However, a fully automatic, easily reproducible and freely accessible pipeline that simultaneously integrates SCS and PCS strategies and supports both library-free and library-based modes is absent. We developed Diamond, a Nextflow-based, containerized, multi-modal DIA-MS data processing pipeline for peptide identification and quantification. Diamond integrated two mainstream workflows for DIA data analysis, namely, SCS and PCS, for use cases both with and without assay libraries. This multi-modal pipeline serves as a versatile, easy-to-use and easily extendable toolbox for large-scale DIA data processing. AVAILABILITY: Diamond is hosted on GitHub (https://github.com/xmuyulab/Diamond) and is released under the highly permissive MIT license to encourage further customization and modification. The Docker image for Diamond is freely accessible at https://hub.docker.com/r/zeroli/diamond.

7.
Nucleic Acids Res ; 47(8): e48, 2019 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-30799483

RESUMO

Characterization of individual cell types is fundamental to the study of multicellular samples. Single-cell RNAseq techniques, which allow high-throughput expression profiling of individual cells, have significantly advanced our ability of this task. Currently, most of the scRNA-seq data analyses are commenced with unsupervised clustering. Clusters are often assigned to different cell types based on the enriched canonical markers. However, this process is inefficient and arbitrary. In this study, we present a technical framework of training the expandable supervised-classifier in order to reveal the single-cell identities as soon as the single-cell expression profile is input. Using multiple scRNA-seq datasets we demonstrate the superior accuracy, robustness, compatibility and expandability of this new solution compared to the traditional methods. We use two examples of the model upgrade to demonstrate how the projected evolution of the cell-type classifier is realized.


Assuntos
Regulação Neoplásica da Expressão Gênica , Neoplasias Pancreáticas/genética , Análise de Célula Única/estatística & dados numéricos , Software , Aprendizado de Máquina Supervisionado , Transcriptoma , Animais , Linhagem da Célula/genética , Análise por Conglomerados , Conjuntos de Dados como Assunto , Perfilação da Expressão Gênica , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Camundongos , RNA Citoplasmático Pequeno/genética , Análise de Sequência de RNA
8.
Bioorg Med Chem ; 28(17): 115642, 2020 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-32773093

RESUMO

DNA polymerase ß (Pol ß) repairs cellular DNA damage. When such damage is inflicted upon the DNA in tumor cells treated with DNA targeted antitumor agents, Pol ß thus diminishes their efficacy. Accordingly, this enzyme has long been a target for antitumor therapy. Although numerous inhibitors of the lyase activity of the enzyme have been reported, none has yet proven adequate for development as a therapeutic agent. In the present study, we developed a new strategy to identify lyase inhibitors that critically engage the lyase active site primary nucleophile Lys72 as part of the binding interface. This involves a parallel evaluation of the effect of the inhibitors on the wild-type DNA polymerase ß (Pol ß) and Pol ß modified with a lysine analogue at position 72. A model panel of five structurally diverse lyase inhibitors identified in our previous studies (only one of which has been published) with unknown modes of binding were used for testing, and one compound, cis-9,10-epoxyoctadecanoic acid, was found to have the desired characteristics. This finding was further corroborated by in silico docking, demonstrating that the predominant mode of binding of the inhibitor involves an important electrostatic interaction between the oxygen atom of the epoxy group and Nε of the main catalytic nucleophile, Lys72. The strategy, which is designed to identify compounds that engage certain structural elements of the target enzyme, could find broader application for identification of ligands with predetermined sites of binding.


Assuntos
DNA Polimerase beta/metabolismo , Ácidos Esteáricos/metabolismo , Sítios de Ligação , Domínio Catalítico , DNA Polimerase beta/antagonistas & inibidores , DNA Polimerase beta/genética , Humanos , Ligantes , Simulação de Acoplamento Molecular , Mutagênese Sítio-Dirigida , Ligação Proteica , Ácidos Esteáricos/química
9.
J Am Chem Soc ; 141(14): 5597-5601, 2019 04 10.
Artigo em Inglês | MEDLINE | ID: mdl-30889951

RESUMO

Genetic code expansion has enabled many noncanonical amino acids to be incorporated into proteins in vitro and in cellulo. These have largely involved α-l-amino acids, reflecting the substrate specificity of natural aminoacyl-tRNA synthetases and ribosomes. Recently, modified E. coli ribosomes, selected using a dipeptidylpuromycin analogue, were employed to incorporate dipeptides and dipeptidomimetics. Presently, we report the in cellulo incorporation of a strongly fluorescent oxazole amino acid (lacking an asymmetric center or α-amino group) by using modified ribosomes and pyrrolysyl-tRNA synthetase (PylRS). Initially, a plasmid encoding the RRM1 domain of putative transcription factor hnRNP LL was cotransformed with plasmid pTECH-Pyl-OP in E. coli cells, having modified ribosomes able to incorporate dipeptides. Cell incubation in a medium containing oxazole 2 resulted in the elaboration of RRM1 containing the oxazole. Green fluorescent protein, previously expressed in vitro with several different oxazole amino acids at position 66, was also expressed in cellulo containing oxazole 2; the incorporation was verified by mass spectrometry. Finally, oxazole 2 was incorporated into position 13 of MreB, a bacterial homologue of eukaryotic cytoskeletal protein actin F. Modified MreB expressed in vitro and in cellulo comigrated with wild type. E. coli cells expressing the modified MreB were strongly fluorescent and retained the E. coli cell rod-like phenotype. For each protein studied, the incorporation of oxazole 2 strongly increased oxazole fluorescence, suggesting its potential utility as a protein tag. These findings also suggest the feasibility of dramatically increasing the repertoire of amino acids that can be genetically encoded for protein incorporation in cellulo.


Assuntos
Aminoácidos/química , Corantes Fluorescentes/química , Proteínas de Fluorescência Verde/biossíntese , Proteínas de Fluorescência Verde/química , Oxazóis/química , Escherichia coli/metabolismo , Ribossomos/metabolismo
10.
Zhejiang Da Xue Xue Bao Yi Xue Ban ; 48(6): 651-656, 2019 12 25.
Artigo em Chinês | MEDLINE | ID: mdl-31955540

RESUMO

OBJECTIVE: To evaluate the efficacy of internal fixation of lateral and medial borders for displaced scapular body fractures via the minimally invasive approach. METHODS: The internal fixation of lateral and medial borders via minimally invasive approach was applied in surgical treatment of 23 patients with scapular body comminuted fractures from January 2014 to June 2018. The lateral approach was made straightly orienting over the lateral border of scapula. The dissection was taken down to the deltoid fascia. The deltoid was retracted cephalically, revealing the external rotators. Blunt dissection was used down to the lateral border between infraspinatus and teres minor, exposing the fracture site. The medial incision was done along the medial border of the scapula over site of the fracture. Dissections were taken down to the fascia and the periosteum. A subperiosteal dissection was then performed to elevate the infraspinatus to the degree necessary to visualize the fracture. The medial and lateral borders of scapula body were fixed with plates and screws in a frame-like way. RESULTS: One patient developed the delayed healing of the incisions due to liquefactive fat necrosis. The other 22 patients showed no complications of the incisions. The glenopolar angle (GPA) of fractured scapula was increased from preoperative (25±12) degrees to postoperative (41±5) degrees (P<0.01). The healing time of fractures healed was 3-8 months, with an average time of (4.4±1.3) months. CONCLUSIONS: The lateral-medial combined fixation through minimally invasive surgical approach for the scapula body fractures allows visualization of fracture reduction without extensive muscular or subcutaneous flaps, and is associated with successful fracture healing and high functional scores of the shoulder.


Assuntos
Fixação de Fratura , Fraturas Ósseas , Procedimentos Cirúrgicos Minimamente Invasivos , Escápula , Fraturas do Ombro , Fixação Interna de Fraturas/normas , Consolidação da Fratura , Fraturas Ósseas/cirurgia , Humanos , Procedimentos Cirúrgicos Minimamente Invasivos/normas , Escápula/lesões , Escápula/cirurgia , Fraturas do Ombro/cirurgia , Resultado do Tratamento
11.
BMC Musculoskelet Disord ; 18(1): 293, 2017 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-28683727

RESUMO

BACKGROUD: Pigmented villonodular synovitis (PVNS) is an uncommon entity of proliferative lesion of the synovium, presenting with different clinical signs and symptoms. PVNS rarely forms an osteolytic lesion in a bone. Here we report a unique case of PVNS with a nodular lesion in the left patella. CASE PRESENTATION: A 37-year-old female was referred to our hospital with complaints of ongoing left knee pain and a painful and palpable mass in her left popliteal fossa. MRI demonstrated a nodular lesion in the left patella, diffuse affected synovial tissue in the left knee and an extra-articular mass in the left popliteal fossa. After a primary diagnosis of PVNS had been established, combined arthroscopic synovectomy and open resection were performed. The postoperative pathological diagnoses of the resected mass from the popliteal fossa, the affected synovial tissue and the lesion in the patella were consistent with PVNS. At 1-year follow-up, no evidence of recurrence was noted. CONCLUSIONS: Based on brief literature review of PNVS, we presented a very rare case of PVNS with a nodular lesion in the left patella, diffuse affected synovial tissue in the left knee and an extra-articular mass in the left popliteal fossa.


Assuntos
Articulação do Joelho/diagnóstico por imagem , Patela/diagnóstico por imagem , Sinovite Pigmentada Vilonodular/diagnóstico por imagem , Adulto , Feminino , Seguimentos , Humanos , Articulação do Joelho/cirurgia , Patela/cirurgia , Sinovite Pigmentada Vilonodular/cirurgia
12.
Anal Chem ; 88(16): 8294-301, 2016 08 16.
Artigo em Inglês | MEDLINE | ID: mdl-27454185

RESUMO

Binding affinity characterization is of great importance for aptamer screening because the dissociation constant (Kd) value is a key parameter for evaluating molecular interaction. However, conventional methods often require sophisticated equipment and time-consuming processing. Here, we present a portable device, Afi-Chip, as an equipment-free, rapid, low-cost, and universal platform for evaluation of the aptamer affinity. The Afi-Chip displays a distance readout based on the reaction of an enzyme catalyzing the decomposition of H2O2 for gas generation to push the movement of ink bar. Taking advantage of translating the recognition signal to distance signal and realizing the regents mixing and quantitative readout on the chip, we successfully monitored the aptamer evolution process and characterized binding affinity of aptamers against multiple types of targets, including small molecule glucose, cancer biomarker protein EpCAM, and tumor cell SW620. We also applied the Afi-Chip for rapid characterization of the affinity between anti-HCG and HCG to demonstrate the generality for the molecular interaction study. All of the Kd values obtained are comparable to those reported in the literature or obtained by sophisticated instruments such as a flow cytometer. The Afi-Chip offers a new approach for equipment-free investigation of molecular interactions, such as aptamer identification, ligand selection monitoring, and drug screening.

13.
J Mol Evol ; 81(5-6): 179-85, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26458993

RESUMO

Amplified in breast cancer 1 (AIB1), also known as steroid receptor coactivator 3 (SRC-3), is a transcriptional coactivator that interacts with nuclear receptors and other transcription factors to enhance their effects on target gene transcription. AIB1, which acts as a major oncogene, is highly expressed in many human cancers, and has been demonstrated to be a key regulator for tumor initiation, progression, metastasis, invasion, and survival. Recruitment of the transcriptional factor CBP/p300 by CBP/p300-interaction domain (CID) of AIB1 is essential for its transcriptional activation function. In this research, we isolated a DNA aptamer AY-3 that binds to AIB1-CID from a random oligonucleotide library using in vitro screening technology-Systematic Evolution of Ligands by EXponential enrichment (SELEX). The binding affinity of the aptamer to AIB1-CID fusion protein is in the nanomolar range. More importantly, the aptamer was found to disrupt in the interaction between p300 and AIB1. This aptamer has great potential to serve as a therapeutic agent for cancer by inhibiting the coactivation of AIB1.


Assuntos
Aptâmeros de Nucleotídeos/metabolismo , Coativador 3 de Receptor Nuclear/metabolismo , Técnica de Seleção de Aptâmeros , Células HEK293 , Humanos , Coativador 3 de Receptor Nuclear/análise , Ligação Proteica , Fatores de Transcrição de p300-CBP/metabolismo
14.
ACS Nano ; 18(1): 436-450, 2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38149638

RESUMO

Rolling circle amplification (RCA) is one of the most promising nucleic acid detection technologies and has been widely used in the molecular diagnosis of disease. Padlock probes are often used to form circular templates, which are the core of RCA. However, RCA often suffers from insufficient specificity and sensitivity. Here we report a reconstruction strategy for conventional padlock probes to promote their overall performance in nucleic acid detection while maintaining probe functions uncompromised. When two rationally designed stem-loops were strategically placed at the two terminals of linear padlock probes, the specificity of target recognition was enhanced and the negative signal was significantly delayed. Our design achieved the best single-base discrimination compared with other structures and over a 1000-fold higher sensitivity than that of the conventional padlock probe, validating the effectiveness of this reconstruction. In addition, the underlying mechanisms of our design were elucidated through molecular dynamics simulations, and the versatility was validated with longer and shorter padlocks targeting the same target, as well as five additional targets (four miRNAs and dengue virus - 2 RNA mimic (DENV-2)). Finally, clinical applicability in multiplex detection was demonstrated by testing real plasma samples. Our exploration of the structures of nucleic acids provided another perspective for developing high-performance detection systems, improving the efficacy of practical detection strategies, and advancing clinical diagnostic research.


Assuntos
MicroRNAs , Técnicas de Amplificação de Ácido Nucleico , MicroRNAs/genética , MicroRNAs/química , Sondas RNA/química
15.
Phytochemistry ; 213: 113747, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37295632

RESUMO

Three previously undescribed griseofulvin derivatives, namely pochonichlamydins A-C, one small polyketide, namely pochonichlamydin D, together with nine known compounds, have been isolated from cultures of the fungus Pochonia chlamydosporia. Their structures with absolute configurations were elucidated on the basis of extensive spectrometric methods and single-crystal X-ray diffraction. Dechlorogriseofulvin and griseofulvin exhibited inhibitory activities against Candida albicans at the concentration of 100 µM, with inhibition rates of 69.1% and 56.3%, respectively. Meanwhile, pochonichlamydin C showed mild cytotoxicity against the human cancer MCF-7 cell line with an IC50 value of 33.1 µM.


Assuntos
Hypocreales , Policetídeos , Humanos , Policetídeos/química , Griseofulvina , Células MCF-7
16.
Adv Sci (Weinh) ; 10(19): e2301814, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37085743

RESUMO

MicroRNAs (miRNAs) can act as oncogenes or tumor suppressors, capable of up or down-regulating gene expression during tumorigenesis; they are diagnostic biomarkers or therapeutic targets for tumors. To detect low abundance of intracellular oncogenic miRNAs (onco-miRNAs) and realize synergistic gene therapy of onco-miRNAs and tumor suppressors, a smart nano-theranostic platform based on dual-miRNAs guided self-feedback tetrahedral entropy-driven DNA circuit is created. The platform as a delivery vehicle is a DNA tetrahedral framework, in which the entropy-driven DNA circuit achieves a dual-miRNAs guided self-feedback, between an in situ amplification of the onco-miRNAs and activation of suppressor miRNAs release. To test this platform, dual-miRNAs are selected, miRNA-155, an up-regulated miRNA, as cancer indicators, and miRNA-122, a down-regulated miRNA as therapy targets in hepatocellular carcinoma, respectively. Through the circuit, the platform to detect onco-miRNAs at femtomolar level as well as visualized miRNAs inside cells, fixed tissues, and mice is programmed. Furthermore, triggered by miRNA-155, preloaded miRNA-122 is amplified via the self-feedback and released into target cells; the sudden increase of miRNA-122 and simultaneous decrease of miRNA-155 synergistically served as therapeutic drugs for gene regulation with enhanced antitumor efficacy and superior biosafety. It is envisioned that this nano-theranostic platform will initiate an essential step toward tumor theranostics in personalized/precise medicine.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , MicroRNAs , Camundongos , Animais , MicroRNAs/genética , MicroRNAs/metabolismo , Medicina de Precisão , Retroalimentação , Entropia , DNA
17.
Research (Wash D C) ; 6: 0179, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377457

RESUMO

Data-independent acquisition (DIA) technology for protein identification from mass spectrometry and related algorithms is developing rapidly. The spectrum-centric analysis of DIA data without the use of spectra library from data-dependent acquisition data represents a promising direction. In this paper, we proposed an untargeted analysis method, Dear-DIAXMBD, for direct analysis of DIA data. Dear-DIAXMBD first integrates the deep variational autoencoder and triplet loss to learn the representations of the extracted fragment ion chromatograms, then uses the k-means clustering algorithm to aggregate fragments with similar representations into the same classes, and finally establishes the inverted index tables to determine the precursors of fragment clusters between precursors and peptides and between fragments and peptides. We show that Dear-DIAXMBD performs superiorly with the highly complicated DIA data of different species obtained by different instrument platforms. Dear-DIAXMBD is publicly available at https://github.com/jianweishuai/Dear-DIA-XMBD.

18.
J Surg Res ; 173(1): 91-8, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21067776

RESUMO

BACKGROUND: The incidence of screw loosening increases significantly in elderly patients with severe osteoporosis. Open vertebral cement augmentation of expandable pedicle screw fixation may improve fixation strength in the osteoporotic vertebrae. MATERIALS AND METHODS: Twenty cadaveric vertebrae (L1-L5) were harvested from six osteoporotic lumbar spines. Axial pullout tests were performed to compare the maximum pullout strength (Fmax) of four methods: 1. Conventional pedicle screws (CPS), 2. Expandable pedicle screws (EPS), 3. Cement augmentation of CPS (cemented-CPS), 4. Cement augmentation of EPS (cemented-EPS). Thirty-six consecutive patients with single-vertebral osteoporotic compressive fractures received posterior decompression and spinal fusion with cemented-CPS (16 cases) or cemented-EPS (20 cases). Plain film and/or CT scan were conducted to evaluate the spinal fusion and fixation effectiveness. RESULTS: The Fmax and energy absorption of cemented-EPS were significantly greater than three control groups. The mean BMD in the severe osteoporosis group was significantly lower than that in the osteoporosis group (t = 2.04, P = 0.036). In the osteoporosis group, cemented-EPS improved the Fmax by 43% and 21% over CPS and cemented-CPS group. In the severe osteoporosis group, cemented-EPS increased the Fmax by 59%, 22%, and 26% over CPS, EPS, and cemented-CPS, respectively. The clinical results showed that all patients suffered from severe osteoporosis. Six months after operation, the JOA and VAS scores in cemented-EPS group improved from 11.4 ± 2.6 and 7.0 ± 1.4 mm to 24.9 ± 1.6 and 2.1 ± 1.3 mm, respectively. No screw loosening occurred in the cemented-EPS group and spinal fusion was achieved. In the cemented-CPS group, four screws loosened (4.2%) according to the radiolucency. Six months after operation, the JOA and VAS scores improved from 13.1 ± 1.9 and 7.6 ± 1.5 mm to 22.8 ± 2.2 and 2.5 ± 1.6 mm, respectively. No cement leaked into the spinal canal in both groups. CONCLUSIONS: Cemented-EPS could increase fixation strength biomechanically. It could reduce the risks of screw loosening in patients with severe osteoporosis, requiring instrumented arthrodesis.


Assuntos
Cimentos Ósseos , Parafusos Ósseos , Fixação Interna de Fraturas/métodos , Fraturas por Compressão/cirurgia , Vértebras Lombares/lesões , Fraturas por Osteoporose/cirurgia , Fraturas da Coluna Vertebral/cirurgia , Vértebras Torácicas/lesões , Idoso , Idoso de 80 Anos ou mais , Fenômenos Biomecânicos , Cadáver , Falha de Equipamento , Feminino , Seguimentos , Fixação Interna de Fraturas/instrumentação , Fraturas por Compressão/diagnóstico por imagem , Humanos , Fixadores Internos , Vértebras Lombares/diagnóstico por imagem , Vértebras Lombares/cirurgia , Masculino , Fraturas por Osteoporose/diagnóstico por imagem , Polimetil Metacrilato , Radiografia , Estudos Retrospectivos , Fraturas da Coluna Vertebral/diagnóstico por imagem , Vértebras Torácicas/diagnóstico por imagem , Vértebras Torácicas/cirurgia , Resultado do Tratamento
19.
J Spinal Disord Tech ; 25(2): 123-8, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21430565

RESUMO

STUDY DESIGN: Low elastic modulus expandable pedicle screw (L-EPS) was inserted into osteoporotic sheep. Biomechanical tests, micro-CT analysis and histologic observation were performed. OBJECTIVE: To find out whether the L-EPS can further improve fixation strength compared to the expandable pedicle screws (EPS) in osteoporotic sheep spine. The screw-bone interface is also detected by micro-computed tomography (CT) and histologic techniques. SUMMARY OF BACKGROUND DATA: There are some studies on EPS in vivo; however, no earlier study has focused on the elastic modulus of EPS, especially in osteoporosis. METHODS: Twelve months after ovariectomy, bilateral pedicles of lumbar vertebrae (L1 to L5) of 4 female sheep were fixed with EPSs. The L-EPS and EPS were randomly placed into each pedicle and then were expanded. Six months later, the sheep were sacrificed and biomechanical tests, micro-CT analysis, and histologic observation were conducted on the isolated specimen vertebrae. RESULTS: Twelve months after ovariectomy, animal model of osteoporosis was established successfully. The axial pull-out strength in L-EPS group was significantly enhanced compared with that in the EPS group (P < 0.05). Micro-CT reconstruction and analysis showed that there was more bone around the L-EPS group compared with those in EPS group (P < 0.05), meanwhile the more homogeneous bone formation distribution around the screws was found in the L-EPS group. Histologic observation showed that newly formed bone extended along the expandable fissures and grew into the center of EPS; meanwhile, the more direct contact and the less fibrous tissue on the screw-bone interface were observed in the L-EPS group. CONCLUSIONS: The L-EPS can further improve the biomechanical fixation strength of EPS in the osteoporotic sheep. The screw elastic matching with surrounding bone is helpful to distribute stress uniformly, relieve the stress shielding effect, and strengthen the screw-bone interface. Although the experience with the L-EPS is very limited and preliminary, results to date indicate that it is of value in treating patients with osteoporosis and warrants further study.


Assuntos
Parafusos Ósseos , Vértebras Lombares/cirurgia , Procedimentos Ortopédicos/instrumentação , Osteoporose/cirurgia , Animais , Fenômenos Biomecânicos , Feminino , Vértebras Lombares/diagnóstico por imagem , Osteoporose/diagnóstico por imagem , Radiografia , Ovinos
20.
Zhongguo Gu Shang ; 35(5): 409-17, 2022 May 25.
Artigo em Chinês | MEDLINE | ID: mdl-35535527

RESUMO

OBJECTIVE: To analyze the difference in clinical efficacy of minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) under Quadrant channel system combined with microscope and percutaneous pedicle screw in the treatment of degenerative lumbar spondylolisthesis. METHODS: A total of 114 patients with single-segment degenerative lumbar spondylolisthesis from June 2015 to February 2019, were divided into three groups according to the surgical methods, such as the MIS-TLIF under the microscope surgery group ( microscope group), MIS-TLIF combined with percutaneous pedicle screw technique surgery group(percutaneous group) and posterior lumbar interbody fusion surgery group (open group). In the microscope group, there were 12 males and 26 females, aged from 42 to 83 years with an average of (63.29±9.09) years. In the percutaneous group, there were 16 males and 22 females, aged from 45 to 82 years with an average of (63.37±7.50) years. In the open group, there were 12 males and 26 females, aged from 51 to 82 years with an average of (63.76±8.21) years. The general conditions of operation, such as operation time, intraoperative blood loss, postoperative drainage, length of surgical incision, frequency of intraoperative fluoroscopy and postoperative time of lying in bed were recorded to analyze the differences in surgical related indicators. Visual analogue scale (VAS) of waist and leg pain in preoperative and postoperative period (3 days, 3 months, 6 months and 12 months) were recorded to evaluate pain remission;Oswestry Disability Index(ODI), Japanese Orthopaedic Association (JOA) score were recorded to evaluate the recovery of waist and leg function on preoperative and postoperative 12 months. The lumbar spondylolisthesis rate and intervertebral height at 12 months after operation were recorded to evaluate the reduction of spondylolisthesis. The Siepe intervertebral fusion standard was used to analyze the intervertebral fusion rate at 12 months after operation. RESULTS: ①All 114 patients were followed up more than 1 year, and no complications related to incision infection occurred. In the microscope group, there was 1 case of subcutaneous effusion 8 days after operation. After percutaneous puncture and drainage, waist compression, and then the healing was delayed. In the percutaneous group, 2 cases of paravertebral muscle necrosis occurred on the side of decompression, and the healing was delayed after debridement. In open group, there was 1 case of intraoperative dural tear, which was packed with free adipose tissue during the operation. There was no postoperative cerebrospinal fluid leakage and other related complications.① Compared with microscope group, percutaneous group increased in operation time, intraoperative blood loss, postoperative wound drainage, surgical incision length, intraoperative fluoroscopy times, and postoperative bed rest time. In open group, intraoperative blood loss, postoperative wound drainage, surgical incision length, and postoperative bed rest time increased, but the intraoperative fluoroscopy time decreased. Compared with percutaneous group, the intraoperative blood loss, wound drainage, surgical incision length, and postoperative bed rest time in open group increased, but operative time and the intraoperative fluoroscopy time decreased(P<0.05). ②ODI and JOA scores of the three groups at 12 months after operation were improved compared with those before operation (P<0.05), but there was no significant difference between the three group(P>0.05). ③Compared with microscope group, the VAS of low back pain in percutaneous group increased at 3 days after operation, and VAS of low back pain in open group increased at 3 days, and 12 month after operation. Compared with percutaneous group, the VAS low back pain score of the open group increased at 3 months after operation (P<0.05). ④ The lumbar spondylolisthesis rate of the three groups of patients at 12 months afrer operation was decreased compared with that before operation(P<0.05), and the intervertebral heigh was increased compared with that before operation(P<0.05), however, there was no significant difference among three groups at 12 months afrer operation(P>0.05). ⑤ There was no significant difference between three groups in the lumbar fusion rate at 12 months afrer operation(P>0.05). CONCLUSION: The MIS-TLIF assisted by microscope and the MIS-TLIF combined with percutaneous pedicle screw are safe and effective to treat the degenerative lumbar spondylolisthesis with single-segment, and the MIS-TLIF assisted by microscope may be more invasive, cause less blood loss and achieve better clinical efficacy.


Assuntos
Dor Lombar , Fusão Vertebral , Espondilolistese , Ferida Cirúrgica , Perda Sanguínea Cirúrgica , Estudos de Casos e Controles , Feminino , Humanos , Vértebras Lombares/cirurgia , Masculino , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Hemorragia Pós-Operatória , Estudos Retrospectivos , Fusão Vertebral/métodos , Espondilolistese/cirurgia , Resultado do Tratamento
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA