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1.
Am J Transplant ; 2024 Apr 18.
Article in English | MEDLINE | ID: mdl-38642712

ABSTRACT

Immune checkpoint inhibitors (ICIs) as a downstaging or bridging therapy for liver transplantation (LT) in hepatocellular carcinoma patients are rapidly increasing. However, the evidence about the feasibility and safety of pre-LT ICI therapy is limited and controversial. To this end, a multicenter, retrospective cohort study was conducted in 11 Chinese centers. The results showed that 83 recipients received pre-LT ICI therapy during the study period. The median post-LT follow-up was 8.1 (interquartile range 3.3-14.6) months. During the short follow-up, 23 (27.7%) recipients developed allograft rejection, and 7 of them (30.4%) were diagnosed by liver biopsy. Multivariate logistics regression analysis showed that the time interval between the last administration of ICI therapy and LT (TLAT) ≥ 30 days was an independent protective factor for allograft rejection (odds ratio = 0.096, 95% confidence interval 0.026-0.357; P < .001). Multivariate Cox analysis showed that allograft rejection was an independent risk factor for overall survival (hazard ratio = 9.960, 95% confidence interval 1.006-98.610; P = .043). We conclude that patients who receive a pre-LT ICI therapy with a TLAT shorter than 30 days have a much higher risk of allograft rejection than those with a TLAT longer than 30 days. The presence of rejection episodes might be associated with higher post-LT mortality.

2.
PLoS Biol ; 19(5): e3001215, 2021 05.
Article in English | MEDLINE | ID: mdl-33979326

ABSTRACT

Perceptual anomalies in individuals with autism spectrum disorder (ASD) have been attributed to an imbalance in weighting incoming sensory evidence with prior knowledge when interpreting sensory information. Here, we show that sensory encoding and how it adapts to changing stimulus statistics during feedback also characteristically differs between neurotypical and ASD groups. In a visual orientation estimation task, we extracted the accuracy of sensory encoding from psychophysical data by using an information theoretic measure. Initially, sensory representations in both groups reflected the statistics of visual orientations in natural scenes, but encoding capacity was overall lower in the ASD group. Exposure to an artificial (i.e., uniform) distribution of visual orientations coupled with performance feedback altered the sensory representations of the neurotypical group toward the novel experimental statistics, while also increasing their total encoding capacity. In contrast, neither total encoding capacity nor its allocation significantly changed in the ASD group. Across both groups, the degree of adaptation was correlated with participants' initial encoding capacity. These findings highlight substantial deficits in sensory encoding-independent from and potentially in addition to deficits in decoding-in individuals with ASD.


Subject(s)
Autism Spectrum Disorder/physiopathology , Visual Perception/physiology , Adolescent , Autism Spectrum Disorder/metabolism , Humans , Male , Models, Theoretical
3.
Article in English | MEDLINE | ID: mdl-38556382

ABSTRACT

BACKGROUND: Pancreatic cancer is a common malignancy with poor prognosis and limited treatment. Here we aimed to investigate the role of host chromosomal instability (CIN) and tumor microbiome in the prognosis of pancreatic cancer patients. METHODS: One hundred formalin-fixed paraffin-embedded (FFPE) pancreatic cancer samples were collected. DNA extracted from FFPE samples were analyzed by low-coverage whole-genome sequencing (WGS) via a customized bioinformatics workflow named ultrasensitive chromosomal aneuploidy detector. RESULTS: Samples are tested according to the procedure of ultrasensitive chromosomal aneuploidy detector (UCAD). We excluded 2 samples with failed quality control, 1 patient lost to follow-up and 6 dead in the perioperative period. The final 91 patients were admitted for the following analyses. Thirteen (14.3%) patients with higher CIN score had worse overall survival (OS) than those with lower CIN score. The top 20 microbes in pancreatic cancer samples included 15 species of bacteria and 5 species of viruses. Patients with high human herpesvirus (HHV)-7 and HHV-5 DNA reads exhibited worse OS. Furthermore, we classified 91 patients into 3 subtypes. Patients with higher CIN score (n =13) had the worst prognosis (median OS 6.9 mon); patients with lower CIN score but with HHV-7/5 DNA load (n = 24) had worse prognosis (median OS 10.6 mon); while patients with lower CIN score and HHV-7/5 DNA negative (n = 54) had the best prognosis (median OS 21.1 mon). CONCLUSIONS: High CIN and HHV-7/5 DNA load were associated with worse survival of pancreatic cancer. The novel molecular subtypes of pancreatic cancer based on CIN and microbiome had prognostic value.

4.
J Neurosci ; 42(14): 2951-2962, 2022 04 06.
Article in English | MEDLINE | ID: mdl-35169018

ABSTRACT

Bayesian inference provides an elegant theoretical framework for understanding the characteristic biases and discrimination thresholds in visual speed perception. However, the framework is difficult to validate because of its flexibility and the fact that suitable constraints on the structure of the sensory uncertainty have been missing. Here, we demonstrate that a Bayesian observer model constrained by efficient coding not only well explains human visual speed perception but also provides an accurate quantitative account of the tuning characteristics of neurons known for representing visual speed. Specifically, we found that the population coding accuracy for visual speed in area MT ("neural prior") is precisely predicted by the power-law, slow-speed prior extracted from fitting the Bayesian observer model to psychophysical data ("behavioral prior") to the point that the two priors are indistinguishable in a cross-validation model comparison. Our results demonstrate a quantitative validation of the Bayesian observer model constrained by efficient coding at both the behavioral and neural levels.SIGNIFICANCE STATEMENT Statistical regularities of the environment play an important role in shaping both neural representations and perceptual behavior. Most previous work addressed these two aspects independently. Here we present a quantitative validation of a theoretical framework that makes joint predictions for neural coding and behavior, based on the assumption that neural representations of sensory information are efficient but also optimally used in generating a percept. Specifically, we demonstrate that the neural tuning characteristics for visual speed in brain area MT are precisely predicted by the statistical prior expectations extracted from psychophysical data. As such, our results provide a normative link between perceptual behavior and the neural representation of sensory information in the brain.


Subject(s)
Motion Perception , Bayes Theorem , Humans , Motion Perception/physiology , Motivation , Neurons , Visual Perception/physiology
5.
Rev Physiol Biochem Pharmacol ; 181: 105-127, 2021.
Article in English | MEDLINE | ID: mdl-32770395

ABSTRACT

Ion channels and transporters (ICT) play important roles in almost all basic cellular processes. During last decades, abundant evidences have been provided that ICT (e.g., Ca2+ and K+ channels) are notable for regulating physiological pancreatic duct cellular function and deregulation of ICT is closely associated with the widely accepted hallmarks of pancreatic ductal adenocarcinoma (PDAC) such as proliferation, apoptosis resistance, invasion, and metastasis. Hence this review focuses on the role of ICT malfunctions in context with the hallmarks of PDAC. After briefly introducing epidemiology and history of molecular oncology of PDAC and summarizing the recent studies on molecular classification systems, we focus then on the exocrine pancreas as a very active secretory gland which considerably impacts the changes in the ion transport system (the transportome) upon malignant transformation. We highlight multiplicity of ICT members (H+ transporters, Ca2+, K+, Na+ and Cl- channels) and their functional impact in PDAC. We also present some selective therapeutic options to interfere with transportome functions and thereby with key mechanisms of malignant progression. This will hopefully contribute to a better clinical outcome based on improved therapeutic strategies for this still extremely deadly disease.


Subject(s)
Carcinoma, Pancreatic Ductal , Pancreatic Neoplasms , Apoptosis , Carcinoma, Pancreatic Ductal/epidemiology , Carcinoma, Pancreatic Ductal/genetics , Cell Proliferation , Gene Expression Regulation, Neoplastic , Humans , Ion Channels , Ion Transport , Pancreatic Neoplasms/epidemiology , Pancreatic Neoplasms/genetics
6.
Anal Chem ; 95(8): 4077-4085, 2023 02 28.
Article in English | MEDLINE | ID: mdl-36787389

ABSTRACT

Herein, by directly limiting the reaction space, an ingenious three-dimensional (3D) DNA walker (IDW) with high walking efficiency is developed for rapid and sensitive detection of miRNA. Compared with the traditional DNA walker, the IDW immobilized by the DNA tetrahedral nanostructure (DTN) brings stronger kinetic and thermodynamic favorability resulting from its improved local concentration and space confinement effect, accompanied by a quite faster reaction speed and much better walking efficiency. Once traces of target miRNA-21 react with the prelocked IDW, the IDW could be largely activated and walk on the interface of the electrode to trigger the cleavage of H2 with the assistance of Mg2+, resulting in the release of amounts of methylene blue (MB) labeled on H2 from the electrode surface and the obvious decrease of the electrode signal. Impressively, the IDW reveals a conversion efficiency as high as 9.33 × 108 in 30 min with a much fast reaction speed, which is at least five times beyond that of typical DNA walkers. Therefore, the IDW could address the inherent challenges of the traditional DNA walker easily: slow walking speed and low efficiency. Notably, the IDW as a DNA nanomachine was utilized to construct a sensitive sensing platform for rapid miRNA-21 detection with a limit of detection (LOD) of 19.8 aM and realize the highly sensitive assay of biomarker miRNA-21 in the total RNA lysates of cancer cell. The strategy thus helps in the design of a versatile nucleic acid conversion and signal amplification approach for practical applications in the areas of biosensing assay, DNA nanotechnology, and clinical diagnosis.


Subject(s)
Biosensing Techniques , MicroRNAs , Nanostructures , MicroRNAs/genetics , Biosensing Techniques/methods , Electrochemical Techniques/methods , DNA/chemistry , Nanostructures/chemistry , Limit of Detection
7.
Opt Express ; 31(20): 33077-33090, 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37859095

ABSTRACT

An easily accessible approach is proposed to create structured beams with various quasicrystal structures and polarization distributions based on multi-beam interference. By controlling the azimuthally-dependent polarization for Q evenly and circularly distributed beams to be interfered, the intensity and polarization structures for the generated quasicrystal field with Q-fold rotational symmetry are flexibly adjusted. Using the diffraction theory for interfering Q vector Gaussian beams, an analytical wave function is derived to reconstruct the polarization-resolved intensities and the distributions of Stokes parameters measured in the experiment. With good agreement between the numerical and experimental results, the derived wave function is further employed to characterize the propagation-variant states of polarization, providing fundamentally important information for the vector quasicrystal beams.

8.
J Org Chem ; 88(6): 3615-3625, 2023 Mar 17.
Article in English | MEDLINE | ID: mdl-36855323

ABSTRACT

A catalytic site-selective ring deconstruction of cyclobuteno[a]naphthalene-4-ones with alcohols is reported, enabling the direct production of a wide range of unsymmetric 1,1-diarylated olefins with good yields and complete regioselectivity. The late-stage application of these resulting terminal olefins demonstrates great possibilities to apply this strategy to complex molecules. The protocol features good functional group compatibility, broad substrate scope, and controllable site selectivity.

9.
World J Surg Oncol ; 21(1): 377, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38037067

ABSTRACT

BACKGROUND: Following neoadjuvant chemotherapy, surgical resection is one of the most preferred treatment options for locally advanced gastric cancer patients. However, the optimal time interval between chemotherapy and surgery is unclear. This review aimed to identify the optimal time interval between neoadjuvant chemotherapy and surgery for advanced gastric cancer. METHODS: Beginning on November 12, 2022, we searched the PubMed, Cochrane Library, Web of Science databases, and Embase.com databases for relevant English-language research. Two authors independently screened the studies, assessed their quality, extracted the data, and analyzed the results. The primary goal was to investigate the relationship between the time interval to surgery (TTS) and long-term survival outcomes for patients. This study has been registered with PROSPERO (CRD42022365196). RESULTS: After an initial search of 4880 articles, the meta-analysis review ultimately included only five retrospective studies. Ultimately, this meta-analysis included 1171 patients, of which 411 patients had TTS of < 4 weeks, 507 patients had TTS of 4-6 weeks, and 253 patients had TTS of > 6 weeks. In survival analysis, patients with TTS of > 6 weeks had poorer overall survival outcomes than patients with TTS of 4-6 weeks (HR = 1.34, 95% CI: 1.03-1.75, P = 0.03). No significant differences were found in terms of disease-free survival the groups. CONCLUSION: Based on the current clinical evidence, patients with locally advanced gastric cancer may benefit better with a TTS of 4-6 weeks; however, this option still needs additional study.


Subject(s)
Stomach Neoplasms , Humans , Stomach Neoplasms/drug therapy , Stomach Neoplasms/surgery , Neoadjuvant Therapy/methods , Retrospective Studies , Disease-Free Survival , Chemotherapy, Adjuvant/methods
10.
Molecules ; 28(5)2023 Feb 26.
Article in English | MEDLINE | ID: mdl-36903419

ABSTRACT

The acidic extracellular microenvironment has become an effective target for diagnosing and treating tumors. A pH (low) insertion peptide (pHLIP) is a kind of peptide that can spontaneously fold into a transmembrane helix in an acidic microenvironment, and then insert into and cross the cell membrane for material transfer. The characteristics of the acidic tumor microenvironment provide a new method for pH-targeted molecular imaging and tumor-targeted therapy. As research has increased, the role of pHLIP as an imaging agent carrier in the field of tumor theranostics has become increasingly prominent. In this paper, we describe the current applications of pHLIP-anchored imaging agents for tumor diagnosis and treatment in terms of different molecular imaging methods, including magnetic resonance T1 imaging, magnetic resonance T2 imaging, SPECT/PET, fluorescence imaging, and photoacoustic imaging. Additionally, we discuss relevant challenges and future development prospects.


Subject(s)
Neoplasms , Precision Medicine , Humans , Peptides/chemistry , Magnetic Resonance Imaging , Hydrogen-Ion Concentration , Tumor Microenvironment
11.
J Sci Food Agric ; 103(1): 164-175, 2023 Jan 15.
Article in English | MEDLINE | ID: mdl-35837792

ABSTRACT

BACKGROUND: Sophora alopecuroides L. is a leguminous plant commonly found in northwest China. In Xinjiang, the fresh herb of S. alopecuroides is often applied as a green fertilizer to the rhizosphere of melon (Cucumis melo) plants at the end of their flowering period, to improve the taste of the fruits. However, the effects of S. alopecuroides-based fertilizers on the microbial community structure of soil and crop-root systems are unclear. In order to study the sweetening mechanism of the S. alopecuroides organic fertilizer, three different varieties of melon were selected. The untreated plants were used as the control (CK) group, and the plants treated with S. alopecuroides-based organic fertilizer were selected as the treatment (T) group. The physical and chemical properties, enzyme activities and microbial community structure of the rhizosphere samples were also determined, and a correlation analysis with the fruit sweetness index was conducted. RESULTS: Sugar content of group T was at least 40% higher than that of group CK. The increase in fruit sugar content positively correlated with the increase in the abundance of beneficial microorganisms, including Pseudomonas, Bacillus, Mycobacterium, Burkholderia, Streptomyces, Acinetobacter, Proteobacteria, Lysobacter, Actinomycetes, Penicillium and Aspergillus. CONCLUSION: Sophora alopecuroides organic fertilizer could alter the composition and function of bacterial and fungal communities and promote the growth of beneficial bacteria in the melon plant rhizosphere. Further, it could increase the content of soluble solids and sugar in the fruits to achieve a sweetening effect. This fertilizer can be applied as a fruit sweetener in melon cultivation, improving the sugar content of the fruit and consequently the sweetness. © 2022 Society of Chemical Industry.


Subject(s)
Cucurbitaceae , Microbiota , Sophora , Fertilizers/analysis , Rhizosphere , Fruit/chemistry , Soil Microbiology , Soil/chemistry , Bacteria/genetics , Sugars
12.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 54(2): 281-286, 2023 Mar.
Article in Zh | MEDLINE | ID: mdl-36949686

ABSTRACT

Objective: To investigate frequency-specific alterations of spontaneous brain activity in first-episode drug-naïve schizophrenia (SZ) patients and the associations with clinical symptoms. Methods: We collected the resting-state functional MRI (rs-fMRI) data from 84 first-episode drug-naïve SZ patients and 94 healthy controls (HCs) and calculated the amplitude of low-frequency fluctuations (ALFF) and regional homogeneity (ReHo) of four frequency bands, including slow-2, slow-3, slow-4, and slow-5. Two-sample t-tests were used to evaluate the intergroup differences in ALFF and ReHo, while partial correlation analyses were conducted to explore the associations between abnormal ALFF and ReHo and the severity of clinical symptoms in the SZ group. Results: Compared with HCs, the SZ group showed reduced ALFF in superior cerebellum and cerebellar vermis across slow-2, slow-3, and slow-4 bands, while increased ALFF was found in left superior temporal gyrus, middle temporal gyrus, and superior temporal pole at slow-4 band. Moreover, reduced ReHo was observed in the right precentral and postcentral gyri at slow-3 band in the SZ group. Additionally, the ALFF of left superior temporal gyrus, middle temporal gyrus, and superior temporal pole in slow-4 band showed a trend of positive correlation with the excited factor score of Positive and Negative Syndrome Scale (PANSS) in the SZ group. Conclusion: Our results suggest that local alterations of spontaneous brain activity were frequency-specific in first-episode drug-naïve SZ patients.


Subject(s)
Schizophrenia , Humans , Brain , Brain Mapping , Temporal Lobe , Magnetic Resonance Imaging
13.
Liver Int ; 42(12): 2620-2631, 2022 12.
Article in English | MEDLINE | ID: mdl-35900248

ABSTRACT

Hepatic macrophages, the key cellular components of the liver, emerge as essential players in liver inflammation, tissue repair and subsequent fibrosis, as well as tumorigenesis. Recently, the TAM receptor tyrosine kinase family, consisting of Tyro3, Axl and MerTK, was found to be a pivotal modulator of macrophages. Activation of macrophage TAM receptor signalling promotes the efferocytosis of apoptotic cells and skews the polarization of macrophages. After briefly reviewing the mechanisms of TAM receptor signalling in macrophage polarization, we focus on their role in liver diseases from acute injury to chronic inflammation, fibrosis and then to tumorigenesis. Notably, macrophage TAM receptor signalling seems to be a two-edged sword for liver diseases. On one hand, the activation of TAM receptor signalling inhibits inflammation and facilitates tissue repair during acute liver injury. On the other hand, continuous activation of the signalling contributes to the process of chronic inflammation into fibrosis and tumorigenesis by evoking hepatic stellate cells and inhibiting anti-tumour immunity. Therefore, targeting macrophage TAM receptors and clarifying its downstream pathways will be exciting prospects for the precaution and treatment of liver diseases, particularly at different stages or statuses.


Subject(s)
Liver Diseases , Macrophages , Humans , Liver Diseases/metabolism , Inflammation/metabolism , Fibrosis , Carcinogenesis/metabolism
14.
J Org Chem ; 87(22): 15644-15652, 2022 11 18.
Article in English | MEDLINE | ID: mdl-36322841

ABSTRACT

A palladium-catalyzed asymmetric annulative allylic alkylation reaction of 2-[(1H-indol-2-yl)methyl]malonates with (E)-but-2-ene-1,4-diyl dicarbonates is described, leading to the regio- and enantioselective synthesis of dihydropyrido[1,2-a]indoles with a chiral cyclic allyl stereocenter adjacent to the ring-junction nitrogen atom in moderate to good yields. The salient features of this protocol include mild conditions, a broad substrate scope, and good compatibility with substituents as well as high regio- and stereoselectivities, providing a catalytic asymmetric entry for fabricating chiral pyridoindole scaffolds.


Subject(s)
Allyl Compounds , Stereoisomerism , Alkylation , Catalysis , Indoles
15.
Acta Pharmacol Sin ; 43(9): 2202-2211, 2022 Sep.
Article in English | MEDLINE | ID: mdl-35042992

ABSTRACT

Cyclic guanosine monophosphate-adenosine monophosphate adenosine synthetase (cGAS) is a DNA sensor that detects and binds to cytosolic DNA to generate cyclic GMP-AMP (cGAMP). As a second messenger, cGAMP mainly activates the adapter protein STING, which induces the production of type I interferons (IFNs) and inflammatory cytokines. Mounting evidence shows that cGAS is extensively involved in the innate immune response, senescence, and tumor immunity, thereby exhibiting a tumor-suppressive function, most of which is mediated by the STING pathway. In contrast, cGAS can also act as an oncogenic factor, mostly by increasing genomic instability through inhibitory effects on DNA repair, suggesting its utility as an antitumor target. This article reviews the roles and the underlying mechanisms of cGAS in cancer, particularly focusing on its dual roles in carcinogenesis and tumor progression, which are probably attributable to its classical and nonclassical functions, as well as approaches targeting cGAS for cancer therapy.


Subject(s)
Interferon Type I , Neoplasms , Carcinogenesis/metabolism , Cytosol/metabolism , DNA/metabolism , Humans , Immunity, Innate , Interferon Type I/metabolism , Nucleotidyltransferases/genetics , Nucleotidyltransferases/metabolism
16.
Zhongguo Dang Dai Er Ke Za Zhi ; 24(10): 1124-1129, 2022 Oct 15.
Article in Zh | MEDLINE | ID: mdl-36305113

ABSTRACT

OBJECTIVES: To study the efficiency of electrocardiogram (ECG) monitor for positioning the catheter tip in the placement of peripherally inserted central venous catheterization (PICC) via lower extremity veins in neonates. METHODS: A total of 120 neonates who were admitted to the neonatal intensive care unit from January 2020 to January 2022 and received PICC via lower extremity veins were enrolled and divided into a control group and an observation group using a random number table (n=60 each). The neonates in the control group were given body surface measurement and postoperative chest X-ray localization, and those in the observation group were given body surface measurement, ECG-guided positioning, and postoperative chest X-ray localization. The two groups were compared in terms of general information, one-time success rate of PICC placement, and time spent on PICC placement, and the efficiency of ECG-guided positioning was evaluated. RESULTS: Compared with the control group, the observation group had a higher one-time success rate of PICC placement (92% vs 75%; P<0.05) and a shorter time spent on PICC placement [(26.5±3.0) min vs (31.8±2.8) min; P<0.05]. ECG-guided positioning had a sensitivity of 90.9% and a specificity of 100% in the PICC placement via lower extremity veins in neonates. CONCLUSIONS: ECG monitor helps to determine the position of catheter tip in the PICC placement via lower extremity veins in neonates and can improve the one-time success rate of PICC placement and reduce the time spent on PICC placement, with a good positioning efficiency.


Subject(s)
Catheterization, Central Venous , Catheterization, Peripheral , Central Venous Catheters , Infant, Newborn , Humans , Electrocardiography , Lower Extremity , Catheters
17.
J Cell Mol Med ; 25(3): 1750-1758, 2021 02.
Article in English | MEDLINE | ID: mdl-33452856

ABSTRACT

Pancreatic ductal adenocarcinoma (PDAC), one of the most lethal human cancers, can be divided into head and body/tail cancers anatomically. We previously reported a prognostic relevance of tumour location in resectable PDAC. This study aimed to further explore the mechanism underlying the molecular diversity between the head and body/tail of PDACs. We detected tumour genomes in 154 resectable (surgery) and non-resectable (biopsy) PDACs using a next-generation sequencing panel. Wilcoxon's rank test or Fisher's exact test was used for evaluating associations between clinical characteristics, mutation frequency and survival probability between the two cohorts. Compared with pancreatic head cancers, pancreatic body/tail cancers showed significantly more enriched genomic alterations in KRAS (97.1% vs 82.4%, P = 0.004) and SMAD4 (42.0% vs 21.2%, P = 0.008). At early stages (I-II), the SMAD4 mutation rate was significantly higher in pancreatic body/tail cancers than pancreatic head cancers (56.0% vs 26.5%, P = 0.021). At late stages (III-IV), pancreatic body/tail cancers presented significantly higher KRAS mutation rate (100.0% vs 75.8%, P = 0.001), higher frequency of MAPK pathway mutation (100% vs 87.8%, P = 0.040) and lower rates of druggable genomic alterations (30.8% vs 57.6%, P = 0.030) than pancreatic head cancers. Our work points out that pancreatic body/tail cancer seems to be more malignant than pancreatic head cancer at late stages.


Subject(s)
Biomarkers, Tumor , Carcinoma, Pancreatic Ductal/genetics , Carcinoma, Pancreatic Ductal/pathology , Genomics , Pancreatic Neoplasms/genetics , Pancreatic Neoplasms/pathology , Carcinoma, Pancreatic Ductal/drug therapy , Carcinoma, Pancreatic Ductal/mortality , Gene Expression Profiling , Gene Expression Regulation, Neoplastic/drug effects , Genomics/methods , High-Throughput Nucleotide Sequencing , Humans , Neoplasm Grading , Neoplasm Staging , Pancreatic Neoplasms/drug therapy , Pancreatic Neoplasms/mortality , Prognosis , Signal Transduction
18.
Anal Chem ; 93(41): 13952-13959, 2021 10 19.
Article in English | MEDLINE | ID: mdl-34613709

ABSTRACT

Herein, we designed a dual 3D DNA nanomachine (DDNM)-mediated catalytic hairpin assembly (DDNM-CHA) to construct an electrochemical biosensor for ultrasensitive detection of miRNA, which possesses quite a faster reaction rate and much higher amplification efficiency than those of traditional catalytic hairpin assembly (CHA). Impressively, since the DDNM skillfully increases the local concentration of reactants and decreases the steric hindrance of substrates simultaneously, the DDNM-CHA could be endowed with higher collision efficiency and more effective reaction compared with traditional CHA, resulting in a hyper conversion efficiency up to 2.78 × 107 only in 25 min. This way, the developed DDNM-CHA could easily conquer the main predicaments: long reaction time and low efficiency. As a proof of the concept, we adopt the gold nanoparticles (AuNPs) and the magnetic nanoparticle (Fe3O4) as the kernel of DNM-A and DNM-B, respectively, and harness the magnetic electrode to directly adsorb the products H1-H2/Fe3O4 for constructing an immobilization-free biosensor for high-speed and ultrasensitive detection of miRNA with a detection limit of 0.14 fM. As a result, the DDNM-CHA we developed carves out a new insight to design a functional DNA nanomachine and evolve the analysis method for practical amplification in the sensing area and promotes the deeper exploration of the nucleic acid signal amplification strategy and DNA nanobiotechnology.


Subject(s)
Biosensing Techniques , DNA, Catalytic , Metal Nanoparticles , MicroRNAs , DNA , Electrochemical Techniques , Gold , Limit of Detection
19.
Anal Chem ; 93(27): 9568-9574, 2021 07 13.
Article in English | MEDLINE | ID: mdl-34210120

ABSTRACT

In this work, an original rolling-circle strand displacement amplification (RC-SDA) was developed by introducing a circle DNA with two recognition domains as a template instead of the limited liner DNA template in traditional strand displacement amplification (SDA), which displayed much shorter reaction time down to 30 min and quite higher conversion efficiency of more than 1.77 × 108 compared with those of traditional strand displacement amplification (SDA) and could be applied to construct a label-free biosensor for ultrasensitive detection of an HIV DNA fragment. Once the target HIV DNA fragment interacts with the template circle DNA, the RC-SDA could be activated to dramatically output amounts of mimic target DNA with the assistance of the Phi29 DNA polymerase and Nb.BbvCI enzyme. In application, while the output products were captured by the DNA tetrahedral nanoprobe (DTNP) modified electrode, the electrochemical tag silver nanoclusters (AgNCs) on DTNP would be released from the electrode surface, accompanied with an obviously decreased electrochemical signal. This way, the developed signal-off biosensor was successfully applied to realize the rapid and ultrasensitive detection of target HIV DNA fragment with a detection limit down to 0.21 fM, which exploits the new generation of a universal strategy beyond the traditional ones for applications in biosensing assay, clinic diagnosis, and DNA nanobiotechnology.


Subject(s)
Biosensing Techniques , Electrochemical Techniques , DNA/genetics , Limit of Detection , Nucleic Acid Amplification Techniques , Silver
20.
Acta Pharmacol Sin ; 42(6): 871-884, 2021 Jun.
Article in English | MEDLINE | ID: mdl-34002042

ABSTRACT

Stroke is a common cause of death and disability. Allisartan isoproxil (ALL) is a new angiotensin II receptor blocker and a new antihypertensive drug discovered and developed in China. In the present study we investigated the therapeutic effects of ALL in stroke-prone renovascular hypertensive rats (RHR-SP) and the underlying mechanisms. The model rats were generated via two-kidney two-clip (2K2C) surgery, which led to 100% of hypertension, 100% of cerebrovascular damage as well as 100% of mortality 1 year after the surgery. Administration of ALL (30 mg · kg-1 · d-1 in diet, for 55 weeks) significantly decreased stroke-related death and prolonged lifespan in RHR-SP, but the survival ALL-treated RHR-SP remained of hypertension and cardiovascular hypertrophy compared with sham-operated normal controls. In addition to cardiac, and aortic protection, ALL treatment for 10 or 12 weeks significantly reduced cerebrovascular damage incidence and scoring, along with a steady reduction of blood pressure (BP) in RHR-SP. Meanwhile, it significantly decreased serum aldosterone and malondialdehyde levels and cerebral NAD(P)H oxidase expressions in RHR-SP. We conducted 24 h continuous BP recording in conscious freely moving RHR-SP, and found that a single intragastric administration of ALL produced a long hypotensive effect lasting for at least 12 h on systolic BP. Taken together, our results in RHR-SP demonstrate that ALL can be used for stroke prevention via BP reduction and organ protection, with the molecular mechanisms related to inhibition of angiotensin-aldosterone system and oxidative stress. This study also provides a valuable scoring for evaluation of cerebrovascular damage and drug efficacy.


Subject(s)
Angiotensin II Type 1 Receptor Blockers/therapeutic use , Antihypertensive Agents/therapeutic use , Aortic Diseases/prevention & control , Biphenyl Compounds/therapeutic use , Cerebrovascular Disorders/prevention & control , Imidazoles/therapeutic use , Stroke/prevention & control , Aldosterone/metabolism , Animals , Aorta/drug effects , Aortic Diseases/complications , Aortic Diseases/mortality , Blood Pressure/drug effects , Brain/drug effects , Brain/pathology , Cerebrovascular Disorders/complications , Cerebrovascular Disorders/mortality , Cerebrovascular Disorders/pathology , Heart/drug effects , Hypertension/complications , Hypertension/mortality , Kaplan-Meier Estimate , Kidney/drug effects , Kidney/pathology , Kidney/surgery , Myocardium/pathology , Oxidative Stress/drug effects , Rats, Sprague-Dawley , Stroke/complications , Stroke/mortality
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