Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 1.797
Filter
Add more filters

Publication year range
1.
Cell ; 171(2): 372-384.e12, 2017 Oct 05.
Article in English | MEDLINE | ID: mdl-28942920

ABSTRACT

MiRNAs are regulatory molecules that can be packaged into exosomes and secreted from cells. Here, we show that adipose tissue macrophages (ATMs) in obese mice secrete miRNA-containing exosomes (Exos), which cause glucose intolerance and insulin resistance when administered to lean mice. Conversely, ATM Exos obtained from lean mice improve glucose tolerance and insulin sensitivity when administered to obese recipients. miR-155 is one of the miRNAs overexpressed in obese ATM Exos, and earlier studies have shown that PPARγ is a miR-155 target. Our results show that miR-155KO animals are insulin sensitive and glucose tolerant compared to controls. Furthermore, transplantation of WT bone marrow into miR-155KO mice mitigated this phenotype. Taken together, these studies show that ATMs secrete exosomes containing miRNA cargo. These miRNAs can be transferred to insulin target cell types through mechanisms of paracrine or endocrine regulation with robust effects on cellular insulin action, in vivo insulin sensitivity, and overall glucose homeostasis.


Subject(s)
Adipose Tissue/cytology , Insulin Resistance , Macrophages/metabolism , MicroRNAs/metabolism , Adipocytes/metabolism , Animals , Cells, Cultured , Glucose/metabolism , Hepatocytes/metabolism , Liver/metabolism , Male , Mice , Mice, Inbred C57BL , Muscle Cells/metabolism , Muscle, Skeletal/metabolism , Signal Transduction
2.
Proc Natl Acad Sci U S A ; 121(22): e2316176121, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38771878

ABSTRACT

The striato-nigral (Str-SN) circuit is composed of medium spiny neuronal projections that are mainly sent from the striatum to the midbrain substantial nigra (SN), which is essential for regulating motor behaviors. Dysfunction of the Str-SN circuitry may cause a series of motor disabilities that are associated with neurodegenerative disorders, such as Huntington's disease (HD). Although the etiology of HD is known as abnormally expanded CAG repeats of the huntingtin gene, treatment of HD remains tremendously challenging. One possible reason is the lack of effective HD model that resembles Str-SN circuitry deficits for pharmacological studies. Here, we first differentiated striatum-like organoids from human pluripotent stem cells (hPSCs), containing functional medium spiny neurons (MSNs). We then generated 3D Str-SN assembloids by assembling striatum-like organoids with midbrain SN-like organoids. With AAV-hSYN-GFP-mediated viral tracing, extensive MSN projections from the striatum to the SN are established, which formed synaptic connection with GABAergic neurons in SN organoids and showed the optically evoked inhibitory postsynaptic currents and electronic field potentials by labeling the striatum-like organoids with optogenetic virus. Furthermore, these Str-SN assembloids exhibited enhanced calcium activity compared to that of individual striatal organoids. Importantly, we further demonstrated the reciprocal projection defects in HD iPSC-derived assembloids, which could be ameliorated by treatment of brain-derived neurotrophic factor. Taken together, these findings suggest that Str-SN assembloids could be used for identifying MSN projection defects and could be applied as potential drug test platforms for HD.


Subject(s)
Huntington Disease , Organoids , Humans , Huntington Disease/pathology , Huntington Disease/metabolism , Organoids/pathology , Organoids/metabolism , Substantia Nigra/pathology , Substantia Nigra/metabolism , Corpus Striatum/pathology , Corpus Striatum/metabolism , Neurons/metabolism , Neurons/pathology , Cell Differentiation , GABAergic Neurons/metabolism , GABAergic Neurons/pathology , Pluripotent Stem Cells/metabolism , Optogenetics
3.
Nucleic Acids Res ; 2024 Sep 11.
Article in English | MEDLINE | ID: mdl-39265120

ABSTRACT

Perturb-Seq combines CRISPR (clustered regularly interspaced short palindromic repeats)-based genetic screens with single-cell RNA sequencing readouts for high-content phenotypic screens. Despite the rapid accumulation of Perturb-Seq datasets, there remains a lack of a user-friendly platform for their efficient reuse. Here, we developed PerturbDB (http://research.gzsys.org.cn/perturbdb), a platform to help users unveil gene functions using Perturb-Seq datasets. PerturbDB hosts 66 Perturb-Seq datasets, which encompass 4 518 521 single-cell transcriptomes derived from the knockdown of 10 194 genes across 19 different cell lines. All datasets were uniformly processed using the Mixscape algorithm. Genes were clustered by their perturbed transcriptomic phenotypes derived from Perturb-Seq data, resulting in 421 gene clusters, 157 of which were stable across different cellular contexts. Through integrating chemically perturbed transcriptomes with Perturb-Seq data, we identified 552 potential inhibitors targeting 1409 genes, including an mammalian target of rapamycin (mTOR) signaling inhibitor, retinol, which was experimentally verified. Moreover, we developed a 'Cancer' module to facilitate the understanding of the regulatory role of genes in cancer using Perturb-Seq data. An interactive web interface has also been developed, enabling users to visualize, analyze and download all the comprehensive datasets available in PerturbDB. PerturbDB will greatly drive gene functional studies and enhance our understanding of the regulatory roles of genes in diseases such as cancer.

4.
Brief Bioinform ; 24(1)2023 01 19.
Article in English | MEDLINE | ID: mdl-36611256

ABSTRACT

Accumulating evidences demonstrate that circular RNA (circRNA) plays an important role in human diseases. Identification of circRNA-disease associations can help for the diagnosis of human diseases, while the traditional method based on biological experiments is time-consuming. In order to address the limitation, a series of computational methods have been proposed in recent years. However, few works have summarized these methods or compared the performance of them. In this paper, we divided the existing methods into three categories: information propagation, traditional machine learning and deep learning. Then, the baseline methods in each category are introduced in detail. Further, 5 different datasets are collected, and 14 representative methods of each category are selected and compared in the 5-fold, 10-fold cross-validation and the de novo experiment. In order to further evaluate the effectiveness of these methods, six common cancers are selected to compare the number of correctly identified circRNA-disease associations in the top-10, top-20, top-50, top-100 and top-200. In addition, according to the results, the observation about the robustness and the character of these methods are concluded. Finally, the future directions and challenges are discussed.


Subject(s)
Neoplasms , RNA, Circular , Humans , RNA, Circular/genetics , Benchmarking , Machine Learning , Neoplasms/genetics , Computational Biology/methods
5.
FASEB J ; 38(1): e23354, 2024 01.
Article in English | MEDLINE | ID: mdl-38085162

ABSTRACT

Head and neck squamous cell carcinoma (HNSCC) is the sixth most common malignancy worldwide, and the development of novel therapeutic strategies for HNSCC requires a profound understanding of tumor cells and the tumor microenvironment (TME). Additionally, HNSCC has a poor prognosis, necessitating the use of genetic markers for predicting clinical outcomes in HNSCC. In this study, we performed single-cell sequencing analysis on tumor tissues from seven HNSCC patients, along with one adjacent normal tissue. Firstly, the analysis of epithelial cell clusters revealed two clusters of malignant epithelial cells, characterized by unique gene expression patterns and dysregulated signaling pathways compared to normal epithelial cells. Secondly, the examination of the TME unveiled extensive crosstalk between fibroblasts and malignant epithelial cells, potentially mediated through ligand-receptor interactions such as COL1A1-SDC1, COL1A1-CD44, and COL1A2-SDC1. Furthermore, transcriptional heterogeneity was observed in immune cells present in the TME, including macrophages and dendritic cells. Finally, leveraging the gene expression profiles of malignant epithelial cells, we developed a prognostic model comprising six genes, which we validated using two independent datasets. These findings shed light on the heterogeneity within HNSCC tumors and the intricate interplay between malignant cells and the TME. Importantly, the developed prognostic model demonstrates high efficacy in predicting the survival outcomes of HNSCC patients.


Subject(s)
Carcinoma , Head and Neck Neoplasms , Humans , Squamous Cell Carcinoma of Head and Neck/genetics , Prognosis , Head and Neck Neoplasms/genetics , Epithelial Cells , Tumor Microenvironment/genetics
6.
Brain ; 147(8): 2826-2841, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38643019

ABSTRACT

Amyotrophic lateral sclerosis (ALS) is a severe motor neuron disease with uncertain genetic predisposition in most sporadic cases. The spatial architecture of cell types and gene expression are the basis of cell-cell interactions, biological function and disease pathology, but are not well investigated in the human motor cortex, a key ALS-relevant brain region. Recent studies indicated single nucleus transcriptomic features of motor neuron vulnerability in ALS motor cortex. However, the brain regional vulnerability of ALS-associated genes and the genetic link between region-specific genes and ALS risk remain largely unclear. Here, we developed an entropy-weighted differential gene expression matrix-based tool (SpatialE) to identify the spatial enrichment of gene sets in spatial transcriptomics. We benchmarked SpatialE against another enrichment tool (multimodal intersection analysis) using spatial transcriptomics data from both human and mouse brain tissues. To investigate regional vulnerability, we analysed three human motor cortex and two dorsolateral prefrontal cortex tissues for spatial enrichment of ALS-associated genes. We also used Cell2location to estimate the abundance of cell types in ALS-related cortex layers. To dissect the link of regionally expressed genes and ALS risk, we performed burden analyses of rare loss-of-function variants detected by whole-genome sequencing in ALS patients and controls, then analysed differential gene expression in the TargetALS RNA-sequencing dataset. SpatialE showed more accurate and specific spatial enrichment of regional cell type markers than multimodal intersection analysis in both mouse brain and human dorsolateral prefrontal cortex. Spatial transcriptomic analyses of human motor cortex showed heterogeneous cell types and spatial gene expression profiles. We found that 260 manually curated ALS-associated genes are significantly enriched in layer 5 of the motor cortex, with abundant expression of upper motor neurons and layer 5 excitatory neurons. Burden analyses of rare loss-of-function variants in Layer 5-associated genes nominated NOMO1 as a novel ALS-associated gene in a combined sample set of 6814 ALS patients and 3324 controls (P = 0.029). Gene expression analyses in CNS tissues revealed downregulation of NOMO1 in ALS, which is consistent with a loss-of-function disease mechanism. In conclusion, our integrated spatial transcriptomics and genomic analyses identified regional brain vulnerability in ALS and the association of a layer 5 gene (NOMO1) with ALS risk.


Subject(s)
Amyotrophic Lateral Sclerosis , Motor Cortex , Amyotrophic Lateral Sclerosis/genetics , Amyotrophic Lateral Sclerosis/pathology , Humans , Mice , Animals , Motor Cortex/metabolism , Motor Cortex/pathology , Transcriptome , Genomics/methods , Prefrontal Cortex/metabolism , Prefrontal Cortex/pathology , Motor Neurons/metabolism , Motor Neurons/pathology , Male
7.
Proc Natl Acad Sci U S A ; 119(15): e2120081119, 2022 04 12.
Article in English | MEDLINE | ID: mdl-35380896

ABSTRACT

Plastid-mediated RNA interference (PM-RNAi) has emerged as a promising strategy for pest control. Expression from the plastid genome of stable double-stranded RNAs (dsRNAs) targeted against essential insect genes can effectively control some herbivorous beetles, but little is known about the efficacy of the transplastomic approach in other groups of pest insects, especially nonchewing insects that do not consume large amounts of leaf material. Here we have investigated the susceptibility of the western flower thrip (WFT, Frankliniella occidentalis), a notorious pest in greenhouses and open fields, to PM-RNAi. We show that WFTs ingest chloroplasts and take up plastid-expressed dsRNAs. We generated a series of transplastomic tobacco plants expressing dsRNAs and hairpin RNAs (hpRNAs) targeted against four essential WFT genes. Unexpectedly, we discovered plastid genome instability in transplastomic plants expressing hpRNAs, suggesting that dsRNA cassettes are preferable over hpRNA cassettes when designing PM-RNAi strategies. Feeding studies revealed that, unlike nuclear transgenic plants, transplastomic plants induced a potent RNAi response in WFTs, causing efficient suppression of the targeted genes and high insect mortality. Our study extends the application range of PM-RNAi technology to an important group of nonchewing insects, reveals design principles for the construction of dsRNA-expressing transplastomic plants, and provides an efficient approach to control one of the toughest insect pests in agriculture and horticulture.


Subject(s)
Pest Control, Biological , Plastids , RNA Interference , RNA, Plant , Thysanoptera , Animals , Pest Control, Biological/methods , Plastids/genetics , RNA, Double-Stranded , RNA, Plant/genetics , Thysanoptera/genetics , Nicotiana/genetics , Nicotiana/parasitology
8.
BMC Med ; 22(1): 147, 2024 Apr 02.
Article in English | MEDLINE | ID: mdl-38561764

ABSTRACT

BACKGROUND: Thyroid nodule (TN) patients in China are subject to overdiagnosis and overtreatment. The implementation of existing technologies such as thyroid ultrasonography has indeed contributed to the improved diagnostic accuracy of TNs. However, a significant issue persists, where many patients undergo unnecessary biopsies, and patients with malignant thyroid nodules (MTNs) are advised to undergo surgery therapy. METHODS: This study included a total of 293 patients diagnosed with TNs. Differential methylation haplotype blocks (MHBs) in blood leukocytes between MTNs and benign thyroid nodules (BTNs) were detected using reduced representation bisulfite sequencing (RRBS). Subsequently, an artificial intelligence blood leukocyte DNA methylation (BLDM) model was designed to optimize the management and treatment of patients with TNs for more effective outcomes. RESULTS: The DNA methylation profiles of peripheral blood leukocytes exhibited distinctions between MTNs and BTNs. The BLDM model we developed for diagnosing TNs achieved an area under the curve (AUC) of 0.858 in the validation cohort and 0.863 in the independent test cohort. Its specificity reached 90.91% and 88.68% in the validation and independent test cohorts, respectively, outperforming the specificity of ultrasonography (43.64% in the validation cohort and 47.17% in the independent test cohort), albeit with a slightly lower sensitivity (83.33% in the validation cohort and 82.86% in the independent test cohort) compared to ultrasonography (97.62% in the validation cohort and 100.00% in the independent test cohort). The BLDM model could correctly identify 89.83% patients whose nodules were suspected malignant by ultrasonography but finally histological benign. In micronodules, the model displayed higher specificity (93.33% in the validation cohort and 92.00% in the independent test cohort) and accuracy (88.24% in the validation cohort and 87.50% in the independent test cohort) for diagnosing TNs. This performance surpassed the specificity and accuracy observed with ultrasonography. A TN diagnostic and treatment framework that prioritizes patients is provided, with fine-needle aspiration (FNA) biopsy performed only on patients with indications of MTNs in both BLDM and ultrasonography results, thus avoiding unnecessary biopsies. CONCLUSIONS: This is the first study to demonstrate the potential of non-invasive blood leukocytes in diagnosing TNs, thereby making TN diagnosis and treatment more efficient in China.


Subject(s)
Thyroid Neoplasms , Thyroid Nodule , Humans , Thyroid Nodule/diagnostic imaging , Thyroid Nodule/genetics , Prospective Studies , Artificial Intelligence , Ultrasonography , Thyroid Neoplasms/diagnosis , Thyroid Neoplasms/pathology , Thyroid Neoplasms/surgery , Retrospective Studies
9.
Small ; 20(33): e2310064, 2024 Aug.
Article in English | MEDLINE | ID: mdl-38607265

ABSTRACT

Limited by the strong oxidation environment and sluggish reconstruction process in oxygen evolution reaction (OER), designing rapid self-reconstruction with high activity and stability electrocatalysts is crucial to promoting anion exchange membrane (AEM) water electrolyzer. Herein, trace Fe/S-modified Ni oxyhydroxide (Fe/S-NiOOH/NF) nanowires are constructed via a simple in situ electrochemical oxidation strategy based on precipitation-dissolution equilibrium. In situ characterization techniques reveal that the successful introduction of Fe and S leads to lattice disorder and boosts favorable hydroxyl capture, accelerating the formation of highly active γ-NiOOH. The Density Functional Theory (DFT) calculations have also verified that the incorporation of Fe and S optimizes the electrons redistribution and the d-band center, decreasing the energy barrier of the rate-determining step (*O→*OOH). Benefited from the unique electronic structure and intermediate adsorption, the Fe/S-NiOOH/NF catalyst only requires the overpotential of 345 mV to reach the industrial current density of 1000 mA cm-2 for 120 h. Meanwhile, assembled AEM water electrolyzer (Fe/S-NiOOH//Pt/C-60 °C) can deliver 1000 mA cm-2 at a cell voltage of 2.24 V, operating at the average energy efficiency of 71% for 100 h. In summary, this work presents a rapid self-reconstruction strategy for high-performance AEM electrocatalysts for future hydrogen economy.

10.
Plant Biotechnol J ; 22(7): 2010-2019, 2024 Jul.
Article in English | MEDLINE | ID: mdl-38426894

ABSTRACT

RNA interference (RNAi) has emerged as an efficient technology for pest control by silencing the essential genes of targeted insects. Owing to its nucleotide sequence-guided working mechanism, RNAi has a high degree of species-specificity without impacts on non-target organisms. However, as plants are inevitably under threat by two or more insect pests in nature, the species-specific mode of RNAi-based technology restricts its wide application for pest control. In this study, we artificially designed an intermediate dsRNA (iACT) targeting two ß-Actin (ACT) genes of sap-sucking pests Bemisia tabaci and Myzus persicae by mutual correction of their mismatches. When expressing hairpin iACT (hpiACT) from tobacco nuclear genome, transgenic plants are well protected from both B. tabaci and M. persicae, either individually or simultaneously, as evidenced by reduced fecundity and suppressed ACT gene expression, whereas expression of hpRNA targeting BtACT or MpACT in transgenic tobacco plants could only confer specific resistance to either B. tabaci or M. persicae, respectively. In sum, our data provide a novel proof-of-concept that two different insect species could be simultaneously controlled by artificial synthesis of dsRNA with sequence optimization, which expands the range of transgenic RNAi methods for crop protection.


Subject(s)
Nicotiana , Plants, Genetically Modified , RNA Interference , RNA, Double-Stranded , RNA, Double-Stranded/genetics , Animals , Plants, Genetically Modified/genetics , Plants, Genetically Modified/parasitology , Nicotiana/genetics , Nicotiana/parasitology , Aphids/genetics , Aphids/physiology , Hemiptera/genetics , Actins/genetics , Actins/metabolism
11.
Brief Bioinform ; 23(1)2022 01 17.
Article in English | MEDLINE | ID: mdl-34864877

ABSTRACT

Increasing evidences have proved that circRNA plays a significant role in the development of many diseases. In addition, many researches have shown that circRNA can be considered as the potential biomarker for clinical diagnosis and treatment of disease. Some computational methods have been proposed to predict circRNA-disease associations. However, the performance of these methods is limited as the sparsity of low-order interaction information. In this paper, we propose a new computational method (KGANCDA) to predict circRNA-disease associations based on knowledge graph attention network. The circRNA-disease knowledge graphs are constructed by collecting multiple relationship data among circRNA, disease, miRNA and lncRNA. Then, the knowledge graph attention network is designed to obtain embeddings of each entity by distinguishing the importance of information from neighbors. Besides the low-order neighbor information, it can also capture high-order neighbor information from multisource associations, which alleviates the problem of data sparsity. Finally, the multilayer perceptron is applied to predict the affinity score of circRNA-disease associations based on the embeddings of circRNA and disease. The experiment results show that KGANCDA outperforms than other state-of-the-art methods in 5-fold cross validation. Furthermore, the case study demonstrates that KGANCDA is an effective tool to predict potential circRNA-disease associations.


Subject(s)
MicroRNAs , RNA, Circular , Computational Biology/methods , MicroRNAs/genetics , Neural Networks, Computer , Pattern Recognition, Automated
12.
Ann Rheum Dis ; 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-39237134

ABSTRACT

OBJECTIVES: Rheumatoid arthritis (RA) is an autoimmune disease characterised by aggressive fibroblast-like synoviocytes (FLSs). Very few RA patients-derived FLSs (RA-FLSs)-specific surface signatures have been identified, and there is currently no approved targeted therapy for RA-FLSs. This study aimed to screen therapeutic aptamers with cell-targeting and cytotoxic properties against RA-FLSs and to uncover the molecular targets and mechanism of action of the screened aptamers. METHODS: We developed a cell-specific and cytotoxic systematic evolution of ligands by exponential enrichment (CSCT-SELEX) method to screen the therapeutic aptamers without prior knowledge of the surface signatures of RA-FLSs. The molecular targets and mechanisms of action of the screened aptamers were determined by pull-down assays and RNA sequencing. The therapeutic efficacy of the screened aptamers was examined in arthritic mouse models. RESULTS: We obtained an aptamer SAPT8 that selectively recognised and killed RA-FLSs. The molecular target of SAPT8 was nucleolin (NCL), a shuttling protein overexpressed on the surface and involved in the tumor-like transformation of RA-FLSs. Mechanistically, SAPT8 interacted with the surface NCL and was internalised to achieve lysosomal degradation of NCL, leading to the upregulation of proapoptotic p53 and downregulation of antiapoptotic B-cell lymphoma 2 (Bcl-2) in RA-FLSs. When administrated systemically to arthritic mice, SAPT8 accumulated in the inflamed FLSs of joints. SAPT8 monotherapy or its combination with tumour necrosis factor (TNF)-targeted biologics was shown to relieve arthritis in mouse models. CONCLUSIONS: CSCT-SELEX could be a promising strategy for developing cell-targeting and cytotoxic aptamers. SAPT8 aptamer selectively ablates RA-FLSs via modulating NCL-p53/Bcl-2 signalling, representing a potential alternative or complementary therapy for RA.

13.
J Med Virol ; 96(3): e29530, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38529528

ABSTRACT

Integration of hepatitis B virus (HBV) DNA into the human genome is recognized as an oncogenic factor and a barrier to hepatitis B cure. In the study, biopsy liver tissues were collected from adolescents and young adults with acute HBV infection younger than or equal to 35 years of age and from HBV-infected infant patients younger than or equal to 6 months of age. A high-throughput sequencing method was used to detect HBV DNA integration. Totally, 12 adolescents, young adults, and 6 infants were included. Among the 12 patients with acute HBV infection, immunohistochemical staining of intrahepatic hepatitis B surface antigen for all displayed negative results, and no HBV DNA integrants in the hepatocyte DNA were confirmed. All infant patients had elevated levels of alanine aminotransferase and high levels of serum HBV DNA. Numerous gene sites of hepatocyte DNA were integrated by HBV DNA for each infant patient, ranging from 120 to 430 integration sites. The fragile histidine triad gene was the high-frequency integrated site in the intragenic region for infant patients. In conclusion, hepatocyte DNA is integrated by HBV DNA in babies with active hepatitis B but seems seldom affected among adolescents and young adults with acute HBV infection. Infantile hepatitis B should be taken seriously considering abundant HBV DNA integration events.


Subject(s)
Hepatitis B, Chronic , Hepatitis B , Infant , Adolescent , Humans , Young Adult , Hepatitis B virus/genetics , DNA, Viral/genetics , Liver/pathology , Hepatitis B Surface Antigens/genetics , Hepatitis B e Antigens , Genomics
14.
Opt Express ; 32(11): 18550-18561, 2024 May 20.
Article in English | MEDLINE | ID: mdl-38859008

ABSTRACT

As a stochastic perturbation, the inter-core crosstalk (IC-XT) severely distorts the signal in multi-core fibers (MCF), especially for long-haul transmission. How to quickly measure and monitor the IC-XT online for an MCF-based space division multiplexing (SDM) system is of special importance. In this paper, we introduce the technology of auxiliary management and control channel (AMCC) to online monitor the IC-XT of MCF, in which the unique advantage of low-frequency auxiliary management and control signal is fully utilized with the limited influence on high-speed data transmission. Specifically, two orthogonal sequences are chosen as monitoring signals for the signal-channel core and the crosstalk-channel core, respectively, followed by digital signal processing (DSP) for the received signal to evaluate the real-time crosstalk accurately. The experimental verifications of XT online monitoring confirm the effectiveness of our proposed method with very small monitoring error (mostly < 0.5 dB) for both heterodyne XT and homodyne XT in the C and L bands, showing its great potential for future SDM systems.

15.
Opt Lett ; 49(5): 1113-1116, 2024 Mar 01.
Article in English | MEDLINE | ID: mdl-38426951

ABSTRACT

We present a stable optical frequency comb (OFC) that utilizes a Fabry-Perot phase modulator. The environmental-induced state variation of the OFC is accurately detected by measuring the relative phase changes of beat signals from its upper and lower sidebands. We then compensate for this variation by controlling OFC bias voltage through a homodyne phase-locked loop. The differential phase detection eliminates the common-mode detection noise, enabling long-term stability of the OFC without requiring any additional reference signal. The relative phase change is only 0.056° over 3800 s. Even under a drastic temperature change, the OFC remains stable, validating the effectiveness of the proposed stabilization method.

16.
Opt Lett ; 49(13): 3693-3696, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38950244

ABSTRACT

A stable photonic delay line with large and tunable delay is essential for large-distance simulation, beamforming, and diverse photonic signal processing applications. Here, we demonstrate a fiber-based tunable photonic delay line (TPDL) with a maximum delay of 905 µs. Its environmental-related delay jitter is compensated for by a homodyne phase-locked loop (PLL). Precise delay tuning is realized by changing the phase of the reference with a minimum tuning step of 0.5 ps without breaking its locking state. The demonstrated delay line shows exceptional stability, as indicated by an overlapping Allan deviation (ADEV) of 2.06 × 10-17 at the averaging time of 1000 s and the delay jitter below 20 fs. Its high stability, wide delay range, wideband characteristics, and precise tunability make the TPDL an ideal photonic delay line for the above-mentioned applications.

17.
Cerebellum ; 2024 Jun 13.
Article in English | MEDLINE | ID: mdl-38869769

ABSTRACT

The CACNA1A gene encodes the alpha-1A subunit of P/Q type voltage-gated calcium channel Cav2.1, which is associated with a broad clinical spectrum and variable symptomatology. While few patients with progressive ataxia caused by CACNA1A missense variants have been reported, here we report three unrelated Chinese patients with progressive ataxia due to de novo missense variants in the CACNA1A gene, including a novel pathogenic variant (c.4999C > G) and a previously reported pathogenic variant (c.4037G > A). Our findings and a systematic literature review show the unique phenotype of progressive ataxia caused by missense variants and enlarge the genetic and clinical spectrum of CACNA1A. This suggests that in addition to routine screening for dynamic mutations, screening for CACNA1A variants is important for clinicians facing patients with progressive ataxia.

18.
Cell Commun Signal ; 22(1): 164, 2024 03 06.
Article in English | MEDLINE | ID: mdl-38448900

ABSTRACT

Pancreatic neuroendocrine tumors (PanNETs), though uncommon, have a high likelihood of spreading to other body parts. Previously, the genetic diversity and evolutionary patterns in metastatic PanNETs were not well understood. To investigate this, we performed multiregion sampling whole-exome sequencing (MRS-WES) on samples from 10 patients who had not received prior treatment for metastatic PanNETs. This included 29 primary tumor samples, 31 lymph node metastases, and 15 liver metastases. We used the MSK-MET dataset for survival analysis and validation of our findings. Our research indicates that mutations in the MEN1/DAXX genes might trigger the early stages of PanNET development. We categorized the patients based on the presence (MEN1/DAXXmut, n = 7) or absence (MEN1/DAXXwild, n = 3) of these mutations. Notable differences were observed between the two groups in terms of genetic alterations and clinically relevant mutations, confirmed using the MSK-MET dataset. Notably, patients with mutations in MEN1/DAXX/ATRX genes had a significantly longer median overall survival compared to those without these mutations (median not reached vs. 43.63 months, p = 0.047). Multiplex immunohistochemistry (mIHC) analysis showed a more prominent immunosuppressive environment in metastatic tumors, especially in patients with MEN1/DAXX mutations. These findings imply that MEN1/DAXX mutations lead PanNETs through a unique evolutionary path. The disease's progression pattern indicates that PanNETs can spread early, even before clinical detection, highlighting the importance of identifying biomarkers related to metastasis to guide personalized treatment strategies.


Subject(s)
Liver Neoplasms , Neuroendocrine Tumors , Pancreatic Neoplasms , Humans , Exome Sequencing , Neuroendocrine Tumors/genetics , Genomics , Liver Neoplasms/genetics , Pancreatic Neoplasms/genetics , Tumor Microenvironment
19.
Mol Pharm ; 21(7): 3407-3415, 2024 Jul 01.
Article in English | MEDLINE | ID: mdl-38822792

ABSTRACT

Transarterial radioembolization (TARE) is a highly effective localized radionuclide therapy that has been successfully used to treat hepatocellular carcinoma (HCC). Extensive research has been conducted on the use of radioactive microspheres (MSs) in TARE, and the development of ideal radioactive MSs is crucial for clinical trials and patient treatment. This study presents the development of a radioactive MS for TARE of HCC. These MSs, referred to as 177Lu-MS@PLGA, consist of poly(lactic-co-glycolic acid) (PLGA) copolymer and radioactive silica MSs, labeled with 177Lu and then coated with PLGA. It has an extremely high level of radiostability. Cellular experiments have shown that it can cause DNA double-strand breaks, leading to cell death. In vivo radiostability of 177Lu-MS@PLGA is demonstrated by microSPECT/CT imaging. In addition, the antitumor study has shown that TARE of 177Lu-MS@PLGA can effectively restrain tumor growth without harmful side effects. Thus, 177Lu-MS@PLGA exhibits significant potential as a radioactive MS for the treatment of HCC.


Subject(s)
Carcinoma, Hepatocellular , Embolization, Therapeutic , Liver Neoplasms , Lutetium , Microspheres , Polylactic Acid-Polyglycolic Acid Copolymer , Radioisotopes , Carcinoma, Hepatocellular/therapy , Carcinoma, Hepatocellular/radiotherapy , Liver Neoplasms/therapy , Liver Neoplasms/radiotherapy , Polylactic Acid-Polyglycolic Acid Copolymer/chemistry , Animals , Humans , Mice , Lutetium/chemistry , Radioisotopes/chemistry , Radioisotopes/administration & dosage , Embolization, Therapeutic/methods , Cell Line, Tumor , Mice, Inbred BALB C , Mice, Nude , Radiopharmaceuticals/chemistry , Radiopharmaceuticals/administration & dosage , Radiopharmaceuticals/therapeutic use , Xenograft Model Antitumor Assays
20.
PLoS Biol ; 19(4): e3001190, 2021 04.
Article in English | MEDLINE | ID: mdl-33844686

ABSTRACT

Chemical insecticides have been heavily employed as the most effective measure for control of agricultural and medical pests, but evolution of resistance by pests threatens the sustainability of this approach. Resistance-conferring mutations sometimes impose fitness costs, which may drive subsequent evolution of compensatory modifier mutations alleviating the costs of resistance. However, how modifier mutations evolve and function to overcome the fitness cost of resistance still remains unknown. Here we show that overexpression of P450s not only confers imidacloprid resistance in the brown planthopper, Nilaparvata lugens, the most voracious pest of rice, but also leads to elevated production of reactive oxygen species (ROS) through metabolism of imidacloprid and host plant compounds. The inevitable production of ROS incurs a fitness cost to the pest, which drives the increase or fixation of the compensatory modifier allele T65549 within the promoter region of N. lugens peroxiredoxin (NlPrx) in the pest populations. T65549 allele in turn upregulates the expression of NlPrx and thus increases resistant individuals' ability to clear the cost-incurring ROS of any source. The frequent involvement of P450s in insecticide resistance and their capacity to produce ROS while metabolizing their substrates suggest that peroxiredoxin or other ROS-scavenging genes may be among the common modifier genes for alleviating the fitness cost of insecticide resistance.


Subject(s)
Hemiptera/drug effects , Insecticide Resistance/drug effects , Neonicotinoids/pharmacology , Nitro Compounds/pharmacology , Oryza/parasitology , Peroxiredoxins/physiology , Adaptation, Biological/drug effects , Adaptation, Biological/genetics , Alleles , Animals , Chromosome Mapping , Gene Expression Regulation, Enzymologic/drug effects , Genes, Insect/drug effects , Genes, Modifier/drug effects , Genes, Modifier/physiology , Genetic Association Studies , Genetic Fitness/drug effects , Hemiptera/physiology , Insecticide Resistance/genetics , Insecticides/pharmacology , Oryza/drug effects , Peroxiredoxins/genetics , Reactive Oxygen Species/metabolism , Toxicity Tests
SELECTION OF CITATIONS
SEARCH DETAIL