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1.
Artigo em Inglês | MEDLINE | ID: mdl-34773681

RESUMO

G-quadruplexes (G4s), non-canonical nucleic acid secondary structure, regulate many biological functions and are considered as potential molecular targets for therapeutics of cancers. However, due to the lack of analytical methods, the regulating mechanism of monogenic G4s is still unclear. Here, we developed a Module Assembled Multifunctional Probes Assay (MAMPA) for visualizing endogenous G4s in individual genes in single cells. Two modular probes separately recognize G4 structures and the adjacent RNA sequences, and the module assembly enables imaging of G4s in an individual RNA with high specificity. Through imaging G4s in several individual genes, we found that G4s were steadily occupied by G4 Binding Proteins (G4BPs) in various mRNAs in every cell line and defined "Occupied G4 Ratio". In all, we demonstrated MAMPA was suitable for most experiment situations and found that Occupied G4 Ratios had the potential to become a new parameter for the study of G4s in living cells.

2.
Adv Mater ; : e2101572, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34611949

RESUMO

Though numerous external-stimuli-triggered tumor therapies, including phototherapy, radiotherapy, and sonodynamic therapy have made great progress in cancer therapy, the low penetration depth of the laser, safety concerns of radiation, the therapeutic resistance, and the spatio-temporal constraints of the specific equipment restrict their convenient clinical applications. What is more, the inherent physiological barriers of the tumor microenvironment (TME), including hypoxia, heterogeneity, and high expression of antioxidant molecules also restrict the efficiency of tumor therapy. As a result, the development of nanoplatforms responsive to endogenous stimuli (such as glucose, acidic pH, cellular redox events, and etc.) has attracted great attention for starvation therapy, ion therapy, prodrug-mediated chemotherapy, or enzyme-catalyzed therapy. In addition, nanomedicines can be modified by some targeted units for precisely locating in subcellular organelles and boosting the destroying of tumor tissue, decreasing the dosage of nanoagents, reducing side effects, and enhancing the therapeutic efficiency. Herein, the properties of the TME, the advantages of endogenous stimuli, and the principles of subcellular-organelle-targeted strategies will be emphasized. Some necessary considerations for the exploitation of precision medicine and clinical translation of multifunctional nanomedicines in the future are also pointed out.

3.
ACS Sens ; 6(10): 3611-3620, 2021 10 22.
Artigo em Inglês | MEDLINE | ID: mdl-34632781

RESUMO

Exosomes that carry multiple proteins from the originating cells are known as emerging biomarkers for tumor diagnostics. However, it is still technically challenging to accurately evaluate subtle differences of exosomal membrane proteins. Here, we developed a rolling circle amplification (RCA)-assisted flow cytometry approach (FCA) to simultaneously profile surface proteins and quantify exosomes. In this work, specific anti-CD63 antibody-conjugated magnetic beads were first utilized to capture exosomes. Then, the captured exosomes were bound with DNA primers, which comprise exosomal surface protein-specific recognition aptamers. The RCA reaction generates repeat DNA sequences for fluorescent probe hybridization. Finally, a conventional flow cytometer was introduced to phenotype exosomal protein markers. Such a sensitive RCA-assisted FCA displays an excellent detection limit of 1.3 × 105 exosome/mL. The variable composition of four protein markers on different cell-derived exosomes was sensitively detected through changing the protein-recognition sequence of the DNA primer, which reveals a heterogeneous pattern. Exosomes from different cell sources could be distinguished by the abundance difference of multiple surface proteins. Furthermore, the developed RCA-assisted FCA enabled quantitative analysis of blood samples from lung cancer patients, indicating its potential for early clinical diagnosis and prognosis of cancer.


Assuntos
Exossomos , Proteínas de Membrana , DNA , Exossomos/genética , Citometria de Fluxo , Humanos , Proteínas de Membrana/genética , Hibridização de Ácido Nucleico
4.
Endocrinol Diabetes Metab ; : e00301, 2021 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-34585841

RESUMO

AIMS: Type 2 diabetes mellitus (T2DM) is a strong risk factor for complications of coronavirus disease 2019 (COVID-19). The effect of T2DM medications on COVID-19 outcomes remains unclear. In a retrospective analysis of a cohort of 131 patients with T2DM hospitalized for COVID-19 in Wuhan, we have previously found that metformin use prior to hospitalization is associated with reduced mortality. The current study aims to investigate the effects of inpatient use of T2DM medications, including metformin, acarbose, insulin and sulfonylureas, on the mortality of COVID-19 patients with T2DM during hospitalization. METHODS: We continue to carry out a retrospective analysis of a cohort of 131 patients with T2DM hospitalized for COVID-19 and treated with different combinations of diabetes medications. RESULTS: We found that patients using metformin (p = .02) and acarbose (p = .04), alone or both together (p = .03), after admission were significantly more likely to survive than those who did not use either metformin or acarbose. 37 patients continued to take metformin after admission and 35 (94.6%) survived. Among the 57 patients who used acarbose after admission, 52 survived (91.2%). A total of 20 patients used both metformin and acarbose, while 57 used neither. Of the 20 dual-use patients, 19 (95.0%) survived. CONCLUSION: Our analyses suggest that inpatient use of metformin and acarbose together or alone during hospitalization should be studied in randomized trials.

5.
Angew Chem Int Ed Engl ; 60(45): 24241-24247, 2021 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-34553468

RESUMO

As a CRISPR-Cas system (clustered regularly interspaced short palindromic repeats and CRISPR associated proteins), Cas14a1 can cis/trans cleave single-stranded DNA (ssDNA). Here, we describe an unreported capacity of Cas14a1: RNA can trigger the trans ssDNA cleavage. This Cas14a1-based RNA-activated detection platform (Amplification, Transcription, Cas14a1-based RNA-activated trans ssDNA cleavage, ATCas-RNA) has an outstanding specificity for the detection of target RNAs with point mutation resolution, which is better than that of the Cas14a1-based ssDNA-activation. Using ATCas-RNA via a fluorophore quencher-labeled ssDNA reporter (FQ), we were able to detect 1 aM pathogenic nucleic acid within 1 h, and achieve 100 % accuracy with 25 milk samples. This platform can serve as a new tool for high-efficiency nucleic acid diagnostics. Importantly, this work can expand our understanding of Cas14a1 and inspire further mechanisms and applications of Class-2 Cas systems.

6.
Chem Soc Rev ; 50(21): 12070-12097, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34533143

RESUMO

Electrocatalysis plays a vital role in energy conversion and storage in modern society. Localized surface plasmon resonance (LSPR) is a highly attractive approach to enhance the electrocatalytic activity and selectivity with solar energy. LSPR excitation can induce the transfer of hot electrons and holes, electromagnetic field enhancement, lattice heating, resonant energy transfer and scattering, in turn boosting a variety of electrocatalytic reactions. Although the LSPR-mediated electrocatalysis has been investigated, the underlying mechanism has not been well explained. Moreover, the efficiency is strongly dependent on the structure and composition of plasmonic metals. In this review, the currently proposed mechanisms for plasmon-mediated electrocatalysis are introduced and the preparation methods to design supported plasmonic nanostructures and related electrodes are summarized. In addition, we focus on the characterization strategies used for verifying and differentiating LSPR mechanisms involved at the electrochemical interface. Following that are highlights of representative examples of direct plasmonic metal-driven and indirect plasmon-enhanced electrocatalytic reactions. Finally, this review concludes with a discussion on the remaining challenges and future opportunities for coupling LSPR with electrocatalysis.

7.
Pak J Pharm Sci ; 34(1): 129-134, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34248012

RESUMO

The aim of this study was to examine the effects of glycosaminoglycan (GAG) from Urechis unicinctus on the P2Y1 receptor pathway and expression of related factors in rat platelets. The concentration of calcium ion (Ca2+) in rat platelets was determined by double wavelength Fura-2 fluorescence spectrophotometry, and the concentrations of inositol trisphosphate (IP3) and glycoprotein IIb/IIIa (GPIIb/IIIa) in rat platelets were measured using the enzymatic immunoassay method. The phosphorylation levels of phospholipase C (PLC), phospholipase A2 (PLA2), protein kinase C (PKC), and p38 mitogen-activated protein kinase (p38MAPK) were also detected by Western blot. It was found that the GAG from U. unicinctus significantly reduced the Ca2+ and IP3 levels in rat platelets (p<0.05, p<0.01). Moreover, medium and high concentrations of GAG significantly reduced the concentration of the platelet membrane GPIIb/IIIa in rats (p<0.05, p<0.01). The phosphorylation levels of PLC, PLA)2), PKC and p38MAPK in rat platelets were also inhibited by GAG and P)2)Y)1) receptor blocker MRS2179 (p<0.05, p<0.01). However, the degree of inhibition of GAG was lower than that of MRS2179. The results laid a foundation for further utilization of the glycosaminoglycan.

8.
Adv Sci (Weinh) ; 8(17): e2004381, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34196474

RESUMO

Glioblastoma (GBM) is the most malignant brain tumor with unmet therapeutic demand. The blood-brain-barrier (BBB) and tumor heterogeneity limit the treatment effectiveness of various interventions. Here, an ultrasound augmented chemo/immuno therapy for GBM using a neutrophil-delivered nanosensitizer, is developed. The sensitizer is composed of a ZnGa2 O4 :Cr3+ (ZGO) core for persistent luminescence imaging and a hollow sono-sensitive TiO2 shell to generate reactive oxygen species (ROS) for controlled drug release. Immune checkpoint inhibitor (Anti-PD-1 antibody) is trapped in the interior of the porous ZGO@TiO2 with paclitaxel (PTX) loaded liposome encapsulation to form ZGO@TiO2 @ALP. Delivered by neutrophils (NEs), ZGO@TiO2 @ALP-NEs can penetrate through BBB for GBM accumulation. After intravenous injection, ultrasound irradiation at GBM sites initiates ROS generation from ZGO@TiO2 @ALP, leading to liposome destruction for PTX and anti-PD-1 antibody release to kill tumors and induce local inflammation, which in-turn attractes more ZGO@TiO2 @ALP-NEs to migrate into tumor sites for augmented and sustained therapy. The treatment enhances the survival rate of the GBM bearing mice from 0% to 40% and endows them with long-term immuno-surveillance for tumor recurrence, providing a new approach for precision therapy against GBM and other cancers.

9.
Angew Chem Int Ed Engl ; 60(42): 22646-22651, 2021 10 11.
Artigo em Inglês | MEDLINE | ID: mdl-34291539

RESUMO

N6 -methyladenosine (m6 A) modification-the most prevalent mammalian RNA internal modification-plays key regulatory roles in mRNA metabolism. Current approaches for m6 A modified RNA analysis limit at bulk-population level, resulting in a loss of spatiotemporal and cell-to-cell variability information. Here we proposed a m6 A-specific in situ hybridization mediated proximity ligation assay (m6 AISH-PLA) for cellular imaging of m6 A RNA, allowing to identify m6 A modification at specific location in RNAs and image m6 A RNA with single-cell and single-molecule resolution. Using m6 AISH-PLA, we investigated the m6 A level and subcellular location of HSP70 RNA103-m6 A in response to heat shock stress, and found an increased m6 A modified ratio and an increased distribution ratio in cytoplasm under heat shock. m6 AISH-PLA can serve in the study of m6 A RNA in single cells for deciphering epitranscriptomic mechanisms and assisting clinical diagnosis.


Assuntos
Adenosina/análogos & derivados , Hibridização In Situ/métodos , Poliésteres/química , RNA/metabolismo , Adenosina/química , Linhagem Celular , Proteínas de Choque Térmico HSP70/genética , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , RNA/química , RNA Mensageiro/metabolismo , Análise de Célula Única
10.
Anal Chem ; 93(20): 7399-7404, 2021 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-33973472

RESUMO

The unique capability of surface plasmon resonance microscopy (SPRM) in single nanoparticle analysis has found use in various chemical and biological applications. While SPRM offers exceptional sensitivity, the statistical analysis of numerous nanoparticles has been extremely laborious and time-consuming. Herein, we presented an image processing software package for nanoparticle analysis in SPRM, which is empowered by a deep learning algorithm. This package enabled fully automated nanoparticle identification, digital counting, three-dimensional tracking of particle locations, and quantification of dwell time and Brownian motion properties. With a built-in image filtering process to improve the contrast, robust identification and analysis have been achieved from SPRM images of low refractive index nanoparticles. This software tool would largely promote the translation of SPRM technology into the digital sensing platform for high throughput sample screening.


Assuntos
Nanopartículas , Ressonância de Plasmônio de Superfície , Algoritmos , Microscopia , Movimento (Física)
11.
Org Lett ; 23(9): 3604-3609, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-33843237

RESUMO

In contrast with the well-developed radical thiol-ene reaction to access anti-Markovnikov-type products, the research on the catalytic Markovnikov-selective hydrothiolation of alkenes is very restricted. Because of the catalyst poisoning of metal catalysts by organosulfur compounds, limited examples of transition-metal-catalyzed thiol-ene reactions have been reported. However, in this work, a directing-group-assisted hydrothiolation of styrenes with thiols by photoredox/cobalt catalysis is found to proceed smoothly to afford Markovnikov-type sulfides with excellent regioselectivity.

12.
J Phys Chem Lett ; 12(17): 4306-4312, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33913708

RESUMO

Noncovalent interaction between small molecules can generate a charge-transfer (CT) state, achieving the effect of a conjugated large molecule as well as a transition-metal complex. Herein, we demonstrate a room-temperature stable dianion biradical conveniently produced by noncovalent intermolecular CT interaction between anthraquinone (AQ) and potassium tert-butoxide (KOtBu). Essentially, CT from KOtBu to AQ boosts absorption bands from the UV to visible and near-infrared (NIR) range, enabling AQ-KOtBu to have new absorption bands around 400, 550, and 900 nm. The absorption bands of AQ-KOtBu are dramatically enhanced after blue-to-green or NIR light excitation. Interestingly, both ground state AQ-KOtBu (C(1)) and photoexcited AQ-KOtBu (C(2)) are quenched by oxygen to produce singlet oxygen. Furthermore, C(1) can be photoactivated by purged nitrogen in solution, and C(2) can be regenerated after the photoexcitation and purged nitrogen in solution, which may serve as a photosensitizer under visible and NIR light excitation.

13.
Sensors (Basel) ; 21(6)2021 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-33803673

RESUMO

Robot grasping is an important direction in intelligent robots. However, how to help robots grasp specific objects in multi-object scenes is still a challenging problem. In recent years, due to the powerful feature extraction capabilities of convolutional neural networks (CNN), various algorithms based on convolutional neural networks have been proposed to solve the problem of grasp detection. Different from anchor-based grasp detection algorithms, in this paper, we propose a keypoint-based scheme to solve this problem. We model an object or a grasp as a single point-the center point of its bounding box. The detector uses keypoint estimation to find the center point and regress to all other object attributes such as size, direction, etc. Experimental results demonstrate that the accuracy of this method is 74.3% in the multi-object grasp dataset VMRD, and the performance on the single-object scene Cornell dataset is competitive with the current state-of-the-art grasp detection algorithm. Robot experiments demonstrate that this method can help robots grasp the target in single-object and multi-object scenes with overall success rates of 94% and 87%, respectively.

14.
Biosens Bioelectron ; 185: 113262, 2021 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-33930753

RESUMO

Nucleic acid-based diagnosis using CRISPR-Cas associated enzymes is essential for rapid infectious disease diagnosis and treatment strategies during a global pandemic. The obstacle has been blossomed CRIPSR-Cas based tools that can monitor wide range of pathogens in clinical samples with ultralow concentrations. Here, a universal nucleic acid magneto-DNA nanoparticle system was exploited for the detection of pathogenic bacteria, based on the collateral cleavage activity of CRISPR-Cas14a and tag-specific primer extension. In the system, the target nucleic acids were amplificated and be separated from mixtures by streptavidin-coated magnetic bead. The collateral cleavage activity of CRISPR-Cas14a can be activated via the tag sequence on the target product. Consequently, the fluorophore quencher reporter can be activated by CRISPR-Cas14a, leading to the increasing response. The exploited universal bacterial diagnostic can distinguish six different bacteria strains with 1 cfu/mL or 1 aM sensitivity, which may provide new strategies to construct fast, accurate, cost-effective and sensitive diagnostic tools in environments with limited resources.


Assuntos
Técnicas Biossensoriais , Sistemas CRISPR-Cas , Bactérias/genética , Sistemas CRISPR-Cas/genética , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , DNA/genética
15.
Res Sq ; 2021 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-33791691

RESUMO

Type 2 diabetes mellitus (T2DM) is a strong risk factor for complications of coronavirus disease 2019 (COVID-19). The effect of T2DM medications on COVID-19 outcomes remains unclear. In a retrospective analysis of a cohort of 131 patients with T2DM hospitalized for COVID-19 in Wuhan, we have previously found that metformin use prior to hospitalization is associated with reduced mortality. Here we continue to investigate the effects of inpatient use of T2DM medications, including metformin, acarbose, insulin, and sulfonylureas, on the mortality of COVID-19 patients with T2DM during hospitalization. We found that patients using metformin and acarbose, alone or both together, after admission were significantly more likely to survive than those who did not use either metformin or acarbose. Thus, our analyses suggest that inpatient use of metformin and acarbose together or alone during hospitalization should be studied in randomized trials.

16.
Medicine (Baltimore) ; 100(9): e24709, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33655936

RESUMO

RATIONALE: Isoelectric focusing electrophoresis (IFE) is currently recognized as the gold standard for detecting oligoclonal bands (OCBs) in cerebrospinal fluid (CSF). To the best of our knowledge, however, no study has reported on type III OCBs using IFE. In this paper, we report on a rare case of multiple myeloma (MM) with Echinococcus granulosus infection diagnosed by IFE. PATIENT CONCERNS: A 71-year-old man complained of weakness of the right lower extremity accompanied with fever (temperature range 37.8°C-38.2°C) for more than 6 months. DIAGNOSES: MM with E granulosus infection. INTERVENTIONS: The IFE results identified a unique monoclonal band, indicating that the patient may have MM in conjunction with a distinct pathogen infection. He received anthelmintic treatment and bortezomib-thalidomide-dexamethasone therapy. OUTCOMES: The patient was followed up for 15 months. During that time, his temperature returned to normal, his Medical Research Council Grading of Muscle Power scale became 5, and his vital signs stabilized. LESSONS: Detection of OCB type III indicated that the patient was diagnosed with MM accompanied by E granulosus infection. Thus, IFE of CSF may be an auxiliary diagnostic method for MM in the future.


Assuntos
Equinococose/diagnóstico , Echinococcus granulosus , Focalização Isoelétrica , Mieloma Múltiplo/diagnóstico , Bandas Oligoclonais/análise , Idoso , Animais , Líquido Cefalorraquidiano/microbiologia , Equinococose/microbiologia , Humanos , Masculino , Mieloma Múltiplo/microbiologia
17.
Life Sci ; 269: 119085, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33482190

RESUMO

Pulmonary fibrosis (PF), which is characterized by excessive matrix formation, may ultimately lead to irreversible lung damage and thus death. Fibroblast activation has been regarded as a central event during PF pathogenesis. In our previous study, we confirmed that the miR-627/high-mobility group box protein 1 (HMGB1)/Nuclear factor kappa beta (NF-κB) axis modulates transforming growth factor beta 1 (TGFß1)-induced pulmonary fibrosis. In the present study, we investigated the upstream factors leading to miR-627 dysregulation in the process of pulmonary fibroblast activation and PF. The lncRNA MIR155 host gene (MIR155HG) was found to be abnormally upregulated in pulmonary fibrosis tissues and TGFß1-stimulated normal human primary lung fibroblasts (NHLFs). By directly binding to miR-627, MIR155HG inhibited miR-627 expression. MIR155HG overexpression enhanced TGFß1-induced increases in HMGB1 protein expression and p65 phosphorylation, NHLF proliferation, and extracellular matrix (ECM) deposition. In contrast, miR-627 overexpression attenuated the TGFß1-induced changes in NHLFs and significantly reversed the effects of MIR155HG overexpression. Under TGFß1 stimulation, miR-627 inhibition promoted, whereas JSH-23 treatment inhibited NF-κB activation; in NHLFs, NF-κB overexpression upregulated, whereas JSH-23 treatment downregulated MIR155HG expression. In tissue samples, HMGB1 protein levels and p65 phosphorylation were increased; MIR155HG was negatively correlated with miR-627 and positively correlated with HMGB1. In conclusion, we validated that the MIR155HG/miR-627/HMGB1/NF-κB axis formed a regulatory loop that modulates TGFß1-induced NHLF activation. Considering the critical role of NHLF activation in PF pathogenesis, the NF-κB/MIR155HG/miR-627/HMGB1 regulatory loop could exert a vital effect on PF pathogenesis. Further in vivo and clinical investigations are required to confirm this model.


Assuntos
Matriz Extracelular/metabolismo , Fibroblastos/citologia , Proteína HMGB1/metabolismo , MicroRNAs/genética , NF-kappa B/metabolismo , Fibrose Pulmonar/patologia , RNA Longo não Codificante/genética , Estudos de Casos e Controles , Proliferação de Células , Fibroblastos/metabolismo , Regulação da Expressão Gênica , Proteína HMGB1/genética , Humanos , Pulmão/citologia , Pulmão/metabolismo , NF-kappa B/genética , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , Transdução de Sinais , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo
18.
Biosens Bioelectron ; 176: 112953, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33418182

RESUMO

The rapid identification of pathogenic microorganisms plays a crucial role in the timely diagnosis and treatment strategies during a global pandemic, especially in resource-limited area. Herein, we present a sensitive biosensor strategy depended on botulinum neurotoxin type A light chain (BoNT/A LC) activated complex assay (BACA). BoNT/A LC, the surrogate of BoNT/A which embodying the most potent biological poisons, could serve as an ultrasensitive signal reporter with high signal-to-noise ratio to avoid common strong background response, poor stability and low intensity of current biosensor methods. A nanoparticle hybridization system, involving specific binding probes that recognize pathogenic 16S rRNAs or SARS-CoV-2 gene site, was developed to measure double-stranded biotinylated target DNA containing a single-stranded overhang using Fluorescence Resonance Energy Transfer (FRET)-based assay and colorimetric method. The method is validated widely by six different bacteria strains and severe acute respiratory related coronavirus 2 (SARS-CoV-2) nucleic acid, demonstrating a single cell or 1 aM nucleic acid detecting sensitivity. This detection strategy offers a solution for general applications and has a great prospect to be a simple instrument-free colorimetric tool, especially when facing public health emergency.


Assuntos
Técnicas Biossensoriais/métodos , Toxinas Botulínicas Tipo A , Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , COVID-19/virologia , Pandemias , SARS-CoV-2/isolamento & purificação , Bactérias/genética , Bactérias/isolamento & purificação , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , Humanos , SARS-CoV-2/genética , Especificidade da Espécie
19.
Dev Dyn ; 250(2): 237-248, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-32969117

RESUMO

BACKGROUND: Polycomb proteins are essential for maintaining stem cell identity across different stem cell niches. However, how they function to maintain stem cell niches is not fully understood. RESULTS: Here we show that the SERTAD protein Taranis (Tara), which is a Polycomb-trithorax group protein, is expressed in the adult testis niche and plays a role in its maintenance in Drosophila. We found that tara is expressed in early cyst cells, likely including somatic cyst stem cells (CySCs) of Drosophila male testis tip region, which houses both germline and somatic cyst stem cells along with the hub cells, forming the stem cell niche. Consistent with its expression, we found that, while loss of tara in germline cells only had minimal effects, tara knockdown in all cells or only in somatic cells of the niche reduced the number of not only somatic cells, but also germline stem cells (GSCs). We further found that Tara might antagonize Notch signaling in CySCs to maintain the stem cell niche. CONCLUSIONS: Our studies suggest that Tara might function in somatic CySCs for GSC maintenance in the Drosophila testis.

20.
Clin Infect Dis ; 72(12): 2203-2205, 2021 06 15.
Artigo em Inglês | MEDLINE | ID: mdl-32710746

RESUMO

Seventy-six days after the coronavirus disease 2019 epidemic was contained in Wuhan, the Chinese government carried out a citywide severe acute respiratory syndrome coronavirus 2 nucleic acid testing initiative for all residents from 14 May to 1 June 2020. Our hospital tested 107 662 residents around Huanan seafood market, uncovering a positivity rate of 0.006%.


Assuntos
COVID-19 , SARS-CoV-2 , China/epidemiologia , Humanos , Alimentos Marinhos
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