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1.
Angew Chem Int Ed Engl ; 61(38): e202205796, 2022 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-35639438

RESUMO

Porous organic polymer films (PFs) with intrinsical porosity and tuneable pore environment are ideally suited for application in electronic devices. However, the huge challenges still exist for construction of electronic devices based on PFs owing to lack of robustness, processability, and controllable preparation. Herein, we report the electrochemical preparation of carbazole-based porous organic polymer films (eCPFs) as switchable materials for the memristors. These eCPFs possess the characteristics of controllable thickness/size, high stability, and excellent porosity. Carbazole and cyano groups are introduced into the eCPFs to constructing electron transfer systems. Thus, the memristors constructed based on these eCPFs exhibit excellent switching performance, reliability, and reproducibility. The electrochemically controllable preparation method of porous organic polymer membranes proposed in this paper provides a feasible idea for the developments of electronic devices.

2.
Nanotechnology ; 33(4)2021 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-34666325

RESUMO

Polyaniline, as a kind of conductive polymer with commercial application prospects, is still under researches in its synthesis and applications. In this work, polyaniline was fabricated on flexible substrates including carbon cloths and polyethylene naphthalate byin situelectropolymerization method. The synthesized flexible electrodes were characterized by scanning electron microscopy, High resolution transmission electron microscope, atomic force microscope, Fourier transform infrared, x-ray diffraction, and x-ray photoelectron spectroscopy. Owing to the conductivity and the reversible redox property, the polyaniline/carbon cloth electrodes show excellent properties such as decent supercapacitor performance and good detection capability toward ascorbic acid. As supercapacitors, the electrodes exhibit a specific capacitance as high as 776 F g-1at a current density of 1 A g-1and a long cycle life of 20 000 times in the three-electrode system. As ascorbic acid sensors, the flexible electrodes demonstrate stable response to ascorbic acid in the range of 1-3000µM with an outstanding sensitivity (4228µA mM-1cm-2), low detection limit (1µM), and a fast response time. This work holds promise for high-performance and low-cost flexible electrodes for both supercapacitors and non-enzymatic ascorbic acid sensors, and may inspire inventions of self-powered electrochemical sensor.

3.
Langmuir ; 35(24): 7650-7658, 2019 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-31063388

RESUMO

In this study, we have prepared novel pyrrole-formaldehyde polymers through polymerizing pyrrole and formaldehyde in the mixture solvent of water and ethanol by using hydrochloric acid as a catalyst. The as-synthesized polymers possess a nitrogen content of 6.7 atom % and are composed of spherical particles with the diameter of approximately 1-3 µm. A series of nitrogen-doped porous carbons with high specific surface areas (680-2340 m2 g-1) were successfully obtained through the activation treatment of the polymer spheres. The porous properties and surface chemistry of the as-prepared porous carbons are tuned by choosing different activating agents and changing the activation temperature. The morphology, porous properties, and chemical composition of the obtained nitrogen-doped porous carbons are revealed by various characterization methods, such as scanning electron microscopy, nitrogen sorption measurement, and X-ray photoelectron spectroscopy. The as-prepared nitrogen-doped porous carbons as gas adsorbents display high carbon dioxide uptake capacities of 3.80-5.81 mmol g-1 at 273 K and 1.0 bar. They also show excellent carbon dioxide adsorption capacities (2.40-3.37 mmol g-1 at 1.0 bar) and good gas selectivities (CO2/N2 selectivities of 16.9-70.2) at 298 K.

4.
J Biol Chem ; 292(21): 8933-8947, 2017 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-28341744

RESUMO

Glioblastoma is the most common malignant brain tumor and has a poor prognosis. Tachykinin receptor neurokinin-1 (NK1R) is a promising target in glioblastoma therapy because of its overexpression in human glioblastoma. NK1R agonists promote glioblastoma cell growth, whereas NK1R antagonists efficiently inhibit cell growth both in vitro and in vivo However, the molecular mechanisms involved in these effects are incompletely understood. ß-Arrestins (ARRBs) serve as scaffold proteins and adapters to mediate intracellular signal transduction. Here we show that the ARRB1-mediated signaling pathway is essential for NK1-mediated glioblastoma cell proliferation. ARRB1 knockdown significantly inhibited NK1-mediated glioblastoma cell proliferation and induced G2/M phase cell cycle arrest. ARRB1 knockdown cells showed remarkable down-regulation of CDC25C/CDK1/cyclin B1 activity. We also demonstrated that ARRB1 mediated prolonged phosphorylation of ERK1/2 and Akt in glioblastoma cells induced by NK1R activation. ERK1/2 and Akt phosphorylation are involved in regulating CDC25C/CDK1/cyclin B1 activity. The lack of long-term ERK1/2 and Akt activation in ARRB1 knockdown cells was at least partly responsible for the delayed cell cycle progression and proliferation. Moreover, we found that ARRB1-mediated ERK1/2 and Akt phosphorylation regulated the transcriptional activity of both NF-κB and AP-1, which were involved in cyclin B1 expression. ARRB1 deficiency increased the sensitivity of glioblastoma cells to the treatment of NK1R antagonists. Taken together, our results suggest that ARRB1 plays an essential role in NK1R-mediated cell proliferation and G2/M transition in glioblastoma cells. Interference with ARRB1-mediated signaling via NK1R may have potential significance for therapeutic strategies targeting glioblastoma.


Assuntos
Fase G2 , Glioblastoma/metabolismo , Sistema de Sinalização das MAP Quinases , Receptores da Neurocinina-1/metabolismo , beta-Arrestina 1/metabolismo , Proteína Quinase CDC2 , Linhagem Celular , Ciclina B1/genética , Ciclina B1/metabolismo , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Técnicas de Silenciamento de Genes , Glioblastoma/genética , Glioblastoma/terapia , Humanos , Proteína Quinase 1 Ativada por Mitógeno/genética , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/genética , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/genética , Proteínas Proto-Oncogênicas c-akt/metabolismo , Receptores da Neurocinina-1/genética , beta-Arrestina 1/genética , Fosfatases cdc25/genética , Fosfatases cdc25/metabolismo
5.
Nature ; 482(7386): 489-94, 2012 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-22358838

RESUMO

Scalable quantum computing can be achieved only if quantum bits are manipulated in a fault-tolerant fashion. Topological error correction--a method that combines topological quantum computation with quantum error correction--has the highest known tolerable error rate for a local architecture. The technique makes use of cluster states with topological properties and requires only nearest-neighbour interactions. Here we report the experimental demonstration of topological error correction with an eight-photon cluster state. We show that a correlation can be protected against a single error on any quantum bit. Also, when all quantum bits are simultaneously subjected to errors with equal probability, the effective error rate can be significantly reduced. Our work demonstrates the viability of topological error correction for fault-tolerant quantum information processing.

6.
Gen Comp Endocrinol ; 237: 98-108, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27570060

RESUMO

OBJECTIVES: We previously found niacin receptor GPR109A was expressed in murine islet beta-cells, and signaling through GPR109A inhibited glucose stimulated insulin secretion (GSIS). However, the expression of GPR109A in human islets and its functional relevance is still not known. METHODS: The expression of GPR109A was examined by antibody staining and in situ hybridization on pancreatic paraffin sections. GPR109A was cloned and expressed in INS-1 islet beta-cells. Intracellular cAMP and GSIS were determined using enzyme-linked immunosorbent assay (ELISA). RESULTS: The expression of GPR109A was confirmed in murine islet beta-cells and further detected in human counterparts by using commercially available polyclonal antibodies. In situ hybridization study detected the transcripts of GPR109A, but not that of closely related GPR109B. Furthermore, GPR109A was significantly reduced in islets from diabetic individuals and animal model of db/db mice as compared to their respective controls. Further, GPR109A levels in insulinoma were also reduced dramatically as compared to islets found in corresponding non-tumor normal tissues. Quantitative RT-PCR analysis demonstrated that GPR109A transcripts were severely down-regulated in rodent insulinoma cell lines as compared to that of freshly isolated islets from mice. Finally, human and murine GPR109A expression cassettes were transfected into INS-1 cells, which resulted in reduced accumulation of cAMP and insulin secretion after incubation with niacin. The effect could be completely abrogated by pretreatment with pertussis toxin. CONCLUSIONS: These results demonstrate that GPR109A is functionally expressed in both human and murine islet beta-cells. However, the role of GPR109A in the prevention of diabetes or insulinoma needs further study.


Assuntos
Diabetes Mellitus Tipo 2/metabolismo , Regulação para Baixo , Células Secretoras de Insulina/metabolismo , Insulina/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Nicotínicos/metabolismo , Idoso , Animais , AMP Cíclico/metabolismo , Regulação para Baixo/efeitos dos fármacos , Feminino , Imunofluorescência , Glucose/farmacologia , Humanos , Secreção de Insulina , Células Secretoras de Insulina/efeitos dos fármacos , Insulinoma/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Nicotínicos/genética , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/genética
7.
PhytoKeys ; 241: 215-220, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38737293

RESUMO

Rediscovery and examination of the type specimen of Frullaniaauriculata S.Hatt. proves that the original type citation of this species contains an error, which is corrected here. Lectotypification for Porellatakakii S.Hatt. is provided.

8.
Front Genet ; 15: 1337525, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38655053

RESUMO

Background: Tumor initiation and metastasis influence tumor immune exclusion and immunosuppression. Long non-coding RNA (lncRNA) LINC01614 is associated with the prognosis and metastasis of several cancers. However, the relationship between LINC01614 and cancer immune infiltration and the biofunction of LINC01614 in head and neck squamous cell carcinoma (HNSC) remain unclear. Methods: The Genotype-Tissue Expression (GTEx) and The Cancer Genome Atlas (TCGA) datasets were used to analyze the expression difference and diagnostic value of LINC01614 in normal and tumor tissues. The correlation of pan-cancer prognosis and tumor stage of LINC01614 was analyzed based on the TCGA database. The pan-cancer association of LINC01614 expression with the tumor microenvironment (TME) including immune infiltration, expression of immune-related genes, and genomic instability parameters, was analyzed using the Spearman correlation method. The correlation between LINC01614 and tumor stemness evaluation indicators, RNA methylation-related genes, and drug resistance was also analyzed. The functional analysis of LINC01614 was performed using the clusterProfiler R package. The protein-protein interaction (PPI) network and ceRNA network of LINC01614 co-expressed genes and miRNA were constructed and visualized by STRING and Cytoscape, respectively. Finally, the cell location and influence of LINC01614 on cell proliferation and metastasis of HNSC cell lines were evaluated using FISH, CCK-8, wound-healing assay, and transwell assay. Results: LINC01614 was found to be overexpressed in 23 cancers and showed a highly sensitive prediction value in nine cancers (AUC >0.85). LINC01614 dysregulation was associated with tumor stage in 12 cancers and significantly influenced the survival outcomes of 26 cancer types, with only Lymphoid Neoplasm Diffuse Large B-cell Lymphoma (DLBC), uterine corpus endometrial carcinoma (UCEC), and bladder urothelial carcinoma (BLCA) showing a benign influence. LINC01614 was also associated with immune cell infiltration, tumor heterogeneity, cancer stemness, RNA methylation modification, and drug resistance. The potential biological function of LINC01614 was verified in HNSC, and it was found to play important roles in proliferation, immune infiltration, immunotherapy response, and metastasis of HNSC. Conclusion: LINC01614 may serve as a cancer diagnosis and prognosis biomarker and an immunotherapy target for specific cancers.

9.
Biomed Pharmacother ; 172: 116320, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38387134

RESUMO

BACKGROUND: Mitochondrial redox imbalance underlies the pathophysiology of type2 diabetes mellitus (T2DM), and is closely related to tissue damage and dysfunction. Studies have shown the beneficial effects of dietary strategies that elevate ß-hydroxybutyrate (BHB) levels in alleviating T2DM. Nevertheless, the role of BHB has not been clearly elucidated. METHODS: We performed a spectral study to visualize the preventive effects of BHB on blood and multiorgan mitochondrial redox imbalance in T2DM mice via using label-free resonance Raman spectroscopy (RRS), and further explored the impact of BHB therapy on the pathology of T2DM mice by histological and biochemical analyses. FINDINGS: Our data revealed that RRS-based mitochondrial redox states assay enabled clear and reliable identification of the improvement of mitochondrial redox imbalance by BHB, evidenced by the reduction of Raman peak intensity at 750 cm-1, 1128 cm-1 and 1585 cm-1 in blood, tissue as well as purified mitochondria of db/db mice and the increase of tissue mitochondrial succinic dehydrogenase (SDH) staining after BHB treatment. Exogenous supplementation of BHB was also found to attenuate T2DM pathology related to mitochondrial redox states, involving organ injury, blood glucose control, insulin resistance and systemic inflammation. INTERPRETATION: Our findings provide strong evidence for BHB as a potential therapeutic strategy targeting mitochondria for T2DM.


Assuntos
Diabetes Mellitus Experimental , Diabetes Mellitus Tipo 2 , Camundongos , Animais , Análise Espectral Raman , Ácido 3-Hidroxibutírico/farmacologia , Mitocôndrias , Oxirredução , Diabetes Mellitus Tipo 2/tratamento farmacológico
10.
Ann Med Surg (Lond) ; 86(7): 4217-4221, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38989227

RESUMO

Introduction and Importance: Postoperative neck hematoma (PNH), a rare complication following thyroidectomy, occurs in only 1.1-3.15% of cases and can lead to life-threatening outcomes. More rarely, delayed PNHs with atypical clinical manifestations and positions have not yet been reported. Early identification and immediate medical intervention are of utmost importance in such cases. Case Presentation: The authors represented a patient with thyroid cancer adherent to the trachea, who underwent post-thyroidectomy, experienced delayed PNH in the retrosternal region and was infected by respiratory pathogens. Meanwhile, the patient developed recurrent laryngeal nerve (RLN) paralysis after surgery. PNH was not identified in the clinical manifestations; instead, it was detected only through successive cervical ultrasound examinations. Clinical Discussion: Although rare, PNH can lead to serious complications, especially delayed complications or those in atypical positions, without neck swelling. When simultaneously with RLN paralysis, the hematoma may be neglected. Therefore, early diagnosis and treatment are crucial. Conclusion: Clinicians should be vigilant of atypical PNH because neck swelling may be absent. Cervical ultrasonography is essential for diagnosis and can be performed multiple times. Cervical CT scans should be part of the routine procedure, while contrast-enhanced ultrasound can help detect active bleeding. Early postoperative antibiotics are recommended if the tumor is closely attached to the trachea.

11.
Exp Ther Med ; 27(1): 3, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38223329

RESUMO

Lipoma is a common type of benign soft tissue tumor that can occur in the shoulders, neck and back, in addition to other body parts. The Retzius space is a small anatomical space between the pubic symphysis and the bladder located extraperitoneally and filled with loose fatty connective tissue. Giant lipomas are rare in the Retzius space. A 61-year-old Chinese male arrived at Beijing Yanhua Hospital (Beijing, China) due to frequent urination, and CT scan images of the lower abdomen observed a large pelvic mass and left inguinal hernia. Preoperative clinical manifestations and auxiliary examination suggested that the tumor originated from the urinary bladder wall. The maximum tumor diameter was ~25 cm and abdominal pressure was increased. Therefore, laparoscopic pelvic tumor resection combined with inguinal hernia repair was attempted. Intraoperatively, the tumor was found to originate from the Retzius space and the postoperative pathological diagnosis was lipoma. The present case report may serve as a reference for minimally invasive treatment of this type of rare disease in future.

12.
Zool Res ; 45(1): 55-68, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38114433

RESUMO

The gastrointestinal tract is essential for food digestion, nutrient absorption, waste elimination, and microbial defense. Single-cell transcriptome profiling of the intestinal tract has greatly enriched our understanding of cellular diversity, functional heterogeneity, and their importance in intestinal tract development and disease. Although such profiling has been extensively conducted in humans and mice, the single-cell gene expression landscape of the pig cecum remains unexplored. Here, single-cell RNA sequencing was performed on 45 572 cells obtained from seven cecal samples in pigs at four different developmental stages (days (D) 30, 42, 150, and 730). Analysis revealed 12 major cell types and 38 subtypes, as well as their distinctive genes, transcription factors, and regulons, many of which were conserved in humans. An increase in the relative proportions of CD8 + T and Granzyme A (low expression) natural killer T cells (GZMA low NKT) cells and a decrease in the relative proportions of epithelial stem cells, Tregs, RHEX + T cells, and plasmacytoid dendritic cells (pDCs) were noted across the developmental stages. Moreover, the post-weaning period exhibited an up-regulation in mitochondrial genes, COX2 and ND2, as well as genes involved in immune activation in multiple cell types. Cell-cell crosstalk analysis indicated that IBP6 + fibroblasts were the main signal senders at D30, whereas IBP6 - fibroblasts assumed this role at the other stages. NKT cells established interactions with epithelial cells and IBP6 + fibroblasts in the D730 cecum through mediation of GZMA-F2RL1/F2RL2 pairs. This study provides valuable insights into cellular heterogeneity and function in the pig cecum at different development stages.


Assuntos
Ceco , Intestinos , Humanos , Camundongos , Animais , Suínos , Ceco/metabolismo , Trato Gastrointestinal , Perfilação da Expressão Gênica/veterinária , Células Epiteliais
13.
Opt Express ; 21(9): 10810-20, 2013 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-23669938

RESUMO

A new stray light analysis method and some suppression principles of panoramic annular lens (PAL) are introduced in this paper. The proposed method is to find stray light paths which are caused by ray splitting on two refractive surfaces of the PAL block and then cut them off. Following this principle, the stray light paths can be eliminated in the design progress by adding specific merit functions into the optical software. The methods to reduce scatter, diffraction and other stray light are also proposed. A new PAL with a field of view (FOV) of 30° ~ 100° × 360° is designed. The stray light is suppressed more than 80% compared with a similar conventional PAL. The stray light path analysis method also can be used in other catadioptric optics.


Assuntos
Algoritmos , Artefatos , Desenho Assistido por Computador , Lentes , Modelos Teóricos , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento
14.
Nat Commun ; 14(1): 6049, 2023 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-37770448

RESUMO

The topology type and the functionalization of pores play an important role in regulating the performance of covalent organic frameworks. Herein, we designed and synthesized the covalent organic framework with hetero-environmental pores using predesigned asymmetrical dialdehyde monomer. According to the results of structural characterization, crystallinity investigation, and theoretical calculation, the hetero-environmental pores of the obtained framework are regarded as the alternant arrangement. The distinctive hetero pore structure leads the designed material to show more advantages as compared with control materials in loading both hydrophobic and hydrophilic antibiotics for wound healing. This dual-antibiotic strategy can expand the antibacterial range as compared with the single antibiotic one, and reduce the generation of drug resistance. In summary, this strategy for designing covalent organic frameworks with hetero-environmental pores can extend the structural variety and provide a pathway for improving the practical application performance of these materials.


Assuntos
Estruturas Metalorgânicas , Antibacterianos/farmacologia , Cicatrização
15.
Neural Regen Res ; 18(6): 1300-1307, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36453415

RESUMO

In Alzheimer's disease, the transporter P-glycoprotein is responsible for the clearance of amyloid-ß in the brain. Amyloid-ß correlates with the sphingomyelin metabolism, and sphingomyelin participates in the regulation of P-glycoprotein. The amyloid cascade hypothesis describes amyloid-ß as the central cause of Alzheimer's disease neuropathology. Better understanding of the change of P-glycoprotein and sphingomyelin along with amyloid-ß and their potential association in the pathological process of Alzheimer's disease is critical. Herein, we found that the expression of P-glycoprotein in APP/PS1 mice tended to increase with age and was significantly higher at 9 and 12 months of age than that in wild-type mice at comparable age. The functionality of P-glycoprotein of APP/PS1 mice did not change with age but was significantly lower than that of wild-type mice at 12 months of age. Decreased sphingomyelin levels, increased ceramide levels, and the increased expression and activity of neutral sphingomyelinase 1 were observed in APP/PS1 mice at 9 and 12 months of age compared with the levels in wild-type mice. Similar results were observed in the Alzheimer's disease mouse model induced by intracerebroventricular injection of amyloid-ß1-42 and human cerebral microvascular endothelial cells treated with amyloid-ß1-42. In human cerebral microvascular endothelial cells, neutral sphingomyelinase 1 inhibitor interfered with the changes of sphingomyelin metabolism and P-glycoprotein expression and functionality caused by amyloid-ß1-42 treatment. Neutral sphingomyelinase 1 regulated the expression and functionality of P-glycoprotein and the levels of sphingomyelin and ceramide. Together, these findings indicate that neutral sphingomyelinase 1 regulates the expression and function of P-glycoprotein via the sphingomyelin/ceramide pathway. These studies may serve as new pursuits for the development of anti-Alzheimer's disease drugs.

16.
Front Cardiovasc Med ; 10: 1082019, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37034341

RESUMO

Background: Major adverse cardiac events (MACE) are more likely to occur when abnormal heart rate recovery (HRR). This study aimed to assess the incremental predictive significance of HRR over exercise stress myocardial perfusion single-photon emission computed tomography (MPS) results for MACE in individuals with suspected coronary artery disease (CAD). Methods: Between January 2014 and December 2017, we continually gathered data on 595 patients with suspected CAD who received cycling exercise stress MPS. HRR at 1, 2, 3, and 4 min were used as study variables to obtain the optimal cut-off values of HRR for MACE. The difference between the peak heart rate achieved during exercise and the heart rate at 1, 2, 3, and 4 min was used to calculate the HRR, as shown in HRR3. Heart rate variations between two locations in time, such as HRR2 min-1 min, were used to establish the slope of HRR. All patients were followed for a minimum of 4 years, with MACE as the follow-up goal. The associations between HRR and MACE were assessed using Cox proportional hazards analyses. Results: Patients with MACE were older (P = 0.001), and they also had higher rates of hypertension, dyslipidemia, diabetes, abnormal MPS findings (SSS ≥ 5%), medication history (all P < 0.001), and lower HRR values (all P < 0.01). Patients with and without MACE did not significantly vary in their HRR4 min-3 min. The optimal cut-off of HRR1, 2, and 3 combined with SSS can stratify the risk of MACE in people with suspected CAD (all P < 0.001). HRR 1, 2, and 3 and its slope were linked to MACE in multivariate analysis, where HRR3 was the most significant risk predictor. With a global X2 increase from 101 to 126 (P < 0.0001), HRR3 demonstrated the greatest improvement in the model's predictive capacity, incorporating clinical data and MPS outcomes. Conclusions: HRR at 3 min has a more excellent incremental prognostic value for predicting MACE in patients with suspected CAD following cycling exercise stress MPS. Therefore, incorporating HRR at 3 min into known predictive models may further improve the risk stratification of the patients.

17.
Front Pharmacol ; 13: 939542, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35935823

RESUMO

Background: Pancreatic adenocarcinoma (PAAD) is one of the most aggressive and fatal gastrointestinal malignancies with high morbidity and mortality worldwide. Accumulating evidence has revealed the clinical significance of the interaction between the hypoxic microenvironment and cancer stemness in pancreatic cancer progression and therapies. This study aims to identify a hypoxia-stemness index-related gene signature for risk stratification and prognosis prediction in PAAD. Methods: The mRNA expression-based stemness index (mRNAsi) data of PAAD samples from The Cancer Genome Atlas (TCGA) database were calculated based on the one-class logistic regression (OCLR) machine learning algorithm. Univariate Cox regression and LASSO regression analyses were then performed to establish a hypoxia-mRNAsi-related gene signature, and its prognostic performance was verified in both the TCGA-PAAD and GSE62452 corhorts by Kaplan-Meier and receiver operating characteristic (ROC) analyses. Additionally, we further validated the expression levels of signature genes using the TCGA, GTEx and HPA databases as well as qPCR experiments. Moreover, we constructed a prognostic nomogram incorporating the eight-gene signature and traditional clinical factors and analyzed the correlations of the risk score with immune infiltrates and immune checkpoint genes. Results: The mRNAsi values of PAAD samples were significantly higher than those of normal samples (p < 0.001), and PAAD patients with high mRNAsi values exhibited worse overall survival (OS). A novel prognostic risk model was successfully constructed based on the eight-gene signature comprising JMJD6, NDST1, ENO3, LDHA, TES, ANKZF1, CITED, and SIAH2, which could accurately predict the 1-, 3-, and 5-year OS of PAAD patients in both the training and external validation datasets. Additionally, the eight-gene signature could distinguish PAAD samples from normal samples and stratify PAAD patients into low- and high-risk groups with distinct OS. The risk score was closely correlated with immune cell infiltration patterns and immune checkpoint molecules. Moreover, calibration analysis showed the excellent predictive ability of the nomogram incorporating the eight-gene signature and traditional clinical factors. Conclusion: We developed a hypoxia-stemness-related prognostic signature that reliably predicts the OS of PAAD. Our findings may aid in the risk stratification and individual treatment of PAAD patients.

18.
Mol Ther Nucleic Acids ; 27: 1078-1091, 2022 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-35228901

RESUMO

Genetic lineage tracing is indispensable to unraveling the origin, fate, and plasticity of cells. However, the intrinsic leakiness in the CreER-loxP system raises concerns on data interpretation. Here, we reported the generation of a novel dual inducible CreER-loxP system with superior labeling characteristics. This two-component system consists of membrane localized CreER (mCreER: CD8α-FRB-CS-CreER) and TEV protease (mTEVp: CD8α-FKBP-TEVp), which are fusion proteins incorporated with the chemically induced dimerization machinery. Rapamycin and tamoxifen induce sequential dimerization of FKBP and FRB, cleavage of CreER from the membrane, and translocation into the nucleus. The labeling leakiness in Ad293 cells reduced dramatically from more than 70% to less than 5%. This tight labeling feature depends largely on the association of mCreER with HSP90, which conceals the TEV protease cutting site between FRB and CreER and thus preventing uninduced cleavage of the membrane-tethering CreER. Membrane-bound CreER also diminished significantly cytotoxicity. Our studies showed mCreER under the control of the rat insulin promoter increased labeling specificity in MIN6 islet beta-cells. Viability and insulin secretion of MIN6 cells remained intact. Our results demonstrate that this novel system can provide more stringent temporal and spatial control of gene expression and will be useful in cell fate probing.

19.
BMC Med Genomics ; 14(1): 99, 2021 04 09.
Artigo em Inglês | MEDLINE | ID: mdl-33836758

RESUMO

BACKGROUND: Potocki-Shaffer syndrome (PSS) is a rare contiguous gene deletion syndrome marked by haploinsufficiency of genes in chromosomal region 11p11.2p12. Approximately 50 cases of PSS have been reported; however, a syndrome with a PSS-like clinical phenotype caused by 11p11.12p12 duplication has not yet been reported. METHODS: 11p11.12p12 duplication syndrome was identified and evaluated using a multidisciplinary protocol. Diagnostic studies included intelligence testing, thorough physical examination, electroencephalography (EEG), magnetic resonance imaging (MRI) of the brain, ultrasonography, biochemical tests and karyotype analysis. Next-generation sequencing analysis clarified the location of the chromosomal variations, which was confirmed by chromosome microarray analysis (CMA). Whole-exome sequencing (WES) was performed to exclude single nucleotide variations (SNVs). A wider literature search was performed to evaluate the correlation between the genes contained in the chromosomal region and clinical phenotypes. RESULTS: The proband was a 36-year-old mother with intellectual disability (ID) and craniofacial anomalies (CFA). She and her older son, who had a similar clinical phenotype, both carried the same 11p11.12p12 duplication with a copy number increase of approximately 10.5 Mb (chr11:40231033_50762504, GRCh37/hg19) in chromosome bands 11p11.12p12. In addition, she gave birth to a child with a normal phenotype who did not carry the 11p11.12p12 duplication. By literature research and DECIPHER, we identified some shared and some distinct features between this duplication syndrome and PSS. One or more of ALX4, SLC35C1, PHF21A and MAPK8IP1 may be responsible for 11p11.12p12 duplication syndrome. CONCLUSIONS: We present the first report of 11p11.12p12 duplication syndrome. It is an interesting case worth reporting. The identification of clinical phenotypes will facilitate genetic counselling. A molecular cytogenetic approach was helpful in identifying the genetic aetiology of the patients and potential candidate genes with triplosensitive effects involved in 11p11.12p12 duplication.


Assuntos
Deficiência Intelectual , Adulto , Criança , Deleção Cromossômica , Transtornos Cromossômicos , Cromossomos Humanos Par 11 , Exostose Múltipla Hereditária , Feminino , Deleção de Genes , Haploinsuficiência , Humanos , Masculino , Fenótipo
20.
Front Genet ; 12: 811833, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35111204

RESUMO

Primary coenzyme Q10 deficiency-6 (COQ10D6), as a rare autosomal recessive disease caused by COQ6 mutations, is characterized by progressive infantile-onset nephrotic syndrome resulting in end-stage renal failure and sensorineural hearing loss. Here, we report two Chinese siblings with COQ10D6 who primarily presented with severe metabolic acidosis, proteinuria, hypoalbuminemia, growth retardation, and muscle hypotonia and died in early infancy. Using whole-exome sequencing and Sanger sequencing, we identified two rare recessive nonsense mutations in the COQ6 gene segregating with disease in affected family members: c.249C > G (p.Tyr83Ter) and c.1381C > T (p.Gln461Ter), resulting in two truncated protein products. Both mutations are located in a highly conserved area and are predicted to be pathogenic. Indeed, the death of our patients in early infancy indicates the pathogenicity of the p.Tyr83Ter and p.Gln461Ter variants and highlights the significance of the two variants for COQ6 enzyme function, which is necessary for the biosynthesis of coenzyme Q10. In conclusion, we discovered a novel compound heterozygous pathogenic variant of the COQ6 gene as a cause of severe COQ10D6 in the two siblings. Based on the clinical history and genetic characteristics of the patients, our cases expand the genotypic spectrum of COQ10D6 and highlight the heterogeneity and severity of clinical features associated with COQ6 mutations. For patients with clinical manifestations suggestive of COQ10D6, early testing for COQ6 mutations is beneficial for disease diagnosis and therapeutic interventions as well as disease prevention in future generations.

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