Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 210
Filtrar
Mais filtros

País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Bioinformatics ; 40(5)2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38632081

RESUMO

MOTIVATION: The clinical translation of mass spectrometry-based proteomics has been challenging due to limited statistical power caused by large technical variability and inter-patient heterogeneity. Bottom-up proteomics provides an indirect measurement of proteins through digested peptides. This raises the question whether peptide measurements can be used directly to better distinguish differentially expressed proteins. RESULTS: We present a novel method called the peptide set test, which detects coordinated changes in the expression of peptides originating from the same protein and compares them to the rest of the peptidome. Applying our method to data from a published spike-in experiment and simulations demonstrates improved sensitivity without compromising precision, compared to aggregation-based approaches. Additionally, applying the peptide set test to compare the tumor proteomes of tamoxifen-sensitive and tamoxifen-resistant breast cancer patients reveals significant alterations in peptide levels of collagen XII, suggesting an association between collagen XII-mediated matrix reassembly and tamoxifen resistance. Our study establishes the peptide set test as a powerful peptide-centric strategy to infer differential expression in proteomics studies. AVAILABILITY AND IMPLEMENTATION: Peptide set test (PepSetTest) is publicly available at https://github.com/JmWangBio/PepSetTest.


Assuntos
Neoplasias da Mama , Peptídeos , Proteômica , Humanos , Proteômica/métodos , Peptídeos/química , Peptídeos/metabolismo , Neoplasias da Mama/metabolismo , Proteoma/metabolismo , Tamoxifeno/farmacologia , Feminino
2.
Stroke ; 2024 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-38920054

RESUMO

BACKGROUND: Dendritic cells (DCs) regulate the immune response associated with T lymphocytes, but their role in stroke remains unclear. In this study, we investigated the causal relationship between DCs and T-cell response in intracerebral hemorrhage (ICH) by focusing on TLRs (toll-like receptors) that may modulate the function of DCs. METHODS: We studied the effects of TLR4, TLR2, and TLR9 on DC-mediated T-cell response and the outcomes of ICH using male C57BL/6 and CD11c-DTx (diphtheria toxin) receptor mice. We administered specific agents intraperitoneally or orally and evaluated the results using flow cytometry, real-time polymerase chain reaction, Western blotting, immunofluorescence staining, histopathology, and behavioral tests. RESULTS: TLR4 and TLR2 activation induces DC maturation and reduces the ratio of regulatory T to T-helper 17 cells in the brain and periphery after ICH. When either of these receptors is activated, it can worsen neuroinflammation and exacerbate ICH outcomes. TLR9 also promotes DC maturation, stabilizing the number of DCs, particularly conventional DCs. TLR9 has the opposite effects on regulatory T/T-helper 17 balance, neuroinflammation, and ICH outcomes compared with TLR4 and TLR2. Upon stimulation, TLR4 and TLR9 may achieve these effects through the p38-MAPK (p38-mitogen-activated protein kinase)/MyD88 (myeloid differentiation primary response gene 88) and indoleamine 2,3-dioxygenase 1 (IDO1)/GCN2 (general control nonderepressible 2) signaling pathways, respectively. DCs act as intermediaries for TLR-mediated T-cell response. CONCLUSIONS: TLR-mediated opposing effects of DCs on T-cell response may provide novel strategies to treat ICH.

3.
Bioinformatics ; 39(11)2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37952162

RESUMO

MOTIVATION: The LINCS L1000 project has collected gene expression profiles for thousands of compounds across a wide array of concentrations, cell lines, and time points. However, conventional analysis methods often fall short in capturing the rich information encapsulated within the L1000 transcriptional dose-response data. RESULTS: We present DOSE-L1000, a database that unravels the potency and efficacy of compound-gene pairs and the intricate landscape of compound-induced transcriptional changes. Our study uses the fitting of over 140 million generalized additive models and robust linear models, spanning the complete spectrum of compounds and landmark genes within the LINCS L1000 database. This systematic approach provides quantitative insights into differential gene expression and the potency and efficacy of compound-gene pairs across diverse cellular contexts. Through examples, we showcase the application of DOSE-L1000 in tasks such as cell line and compound comparisons, along with clustering analyses and predictions of drug-target interactions. DOSE-L1000 fosters applications in drug discovery, accelerating the transition to omics-driven drug development. AVAILABILITY AND IMPLEMENTATION: DOSE-L1000 is publicly available at https://doi.org/10.5281/zenodo.8286375.


Assuntos
Descoberta de Drogas , Transcriptoma , Humanos , Células MCF-7 , Descoberta de Drogas/métodos
4.
Plant Physiol ; 191(1): 515-527, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36087013

RESUMO

Grain cadmium (Cd) is translocated from source to sink tissues exclusively via phloem, though the phloem Cd unloading transporter has not been identified yet. Here, we isolated and functionally characterized a defensin-like gene DEFENSIN 8 (DEF8) highly expressed in rice (Oryza sativa) grains and induced by Cd exposure in seedling roots. Histochemical analysis and subcellular localization detected DEF8 expression preferentially in pericycle cells and phloem of seedling roots, as well as in phloem of grain vasculatures. Further analysis demonstrated that DEF8 is secreted into extracellular spaces possibly by vesicle trafficking. DEF8 bound to Cd in vitro, and Cd efflux from protoplasts as well as loading into xylem vessels decreased in the def8 mutant seedlings compared with the wild type. At maturity, significantly less Cd accumulation was observed in the mutant grains. These results suggest that DEF8 is a dual function protein that facilitates Cd loading into xylem and unloading from phloem, thus mediating Cd translocation from roots to shoots and further allocation to grains, representing a phloem Cd unloading regulator. Moreover, essential mineral nutrient accumulation as well as important agronomic traits were not affected in the def8 mutants, suggesting DEF8 is an ideal target for breeding low grain Cd rice.


Assuntos
Cádmio , Oryza , Cádmio/metabolismo , Oryza/genética , Oryza/metabolismo , Floema/metabolismo , Melhoramento Vegetal , Grão Comestível/metabolismo , Plântula/metabolismo , Raízes de Plantas/metabolismo , Defensinas/genética , Defensinas/análise , Defensinas/metabolismo
5.
Arch Microbiol ; 206(4): 148, 2024 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-38462558

RESUMO

Pseudomonas aeruginosa is an opportunistic gram-negative pathogenic microorganism that poses a significant challenge in clinical treatment. Antibiotics exhibit limited efficacy against mature biofilm, culminating in an increase in the number of antibiotic-resistant strains. Therefore, novel strategies are essential to enhance the effectiveness of antibiotics against Pseudomonas aeruginosa biofilms. D-histidine has been previously identified as a prospective anti-biofilm agent. However, limited attention has been directed towards its impact on Pseudomonas aeruginosa. Therefore, this study was undertaken to explore the effect of D-histidine on Pseudomonas aeruginosa in vitro. Our results demonstrated that D-histidine downregulated the mRNA expression of virulence and quorum sensing (QS)-associated genes in Pseudomonas aeruginosa PAO1 without affecting bacterial growth. Swarming and swimming motility tests revealed that D-histidine significantly reduced the motility and pathogenicity of PAO1. Moreover, crystal violet staining and confocal laser scanning microscopy demonstrated that D-histidine inhibited biofilm formation and triggered the disassembly of mature biofilms. Notably, D-histidine increased the susceptibility of PAO1 to amikacin compared to that in the amikacin-alone group. These findings underscore the efficacy of D-histidine in combating Pseudomonas aeruginosa by reducing biofilm formation and increasing biofilm disassembly. Moreover, the combination of amikacin and D-histidine induced a synergistic effect against Pseudomonas aeruginosa biofilms, suggesting the potential utility of D-histidine as a preventive strategy against biofilm-associated infections caused by Pseudomonas aeruginosa.


Assuntos
Amicacina , Infecções por Pseudomonas , Humanos , Amicacina/farmacologia , Amicacina/metabolismo , Amicacina/uso terapêutico , Pseudomonas aeruginosa , Histidina/farmacologia , Histidina/metabolismo , Histidina/uso terapêutico , Biofilmes , Percepção de Quorum , Antibacterianos/química , Infecções por Pseudomonas/microbiologia , Fatores de Virulência/metabolismo
6.
BMC Med Imaging ; 24(1): 115, 2024 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-38762466

RESUMO

Cerebral infarction is a common neurological disease with high rates of morbidity, mortality, and recurrence, posing a great threat to human life and health. Cerebral infarction is the second leading cause of death in the world and the leading cause of long-term disability in humans. The results of the third national retrospective sampling survey on causes of death in 2008 showed that cerebral infarction has become the leading cause of death in China and its mortality rate is 4-5 times that of European and American countries. Therefore, this article proposed a study on the predictive value of Cmmi-MHR combined with thromboelastography parameters that was performed for acute cerebral infarction. This paper mainly proposed a high frame rate imaging technology and analyzed its algorithm. In this article, in the experimental part, an in-depth analysis of the predictive value of the Monocyte-to-high-density lipoprotein cholesterol ratio (MHR) combined with thromboelastography parameters was performed for acute cerebral infarction. The final experimental results showed that HDL (OR = 1.695%, P-trend = 0.049) had a probability of death within 90 days of hospitalization (OR = 0.81, 95% CI = 1.06-3.11, P-trend = 0.523). There were no significant differences in mortality rate after 90 days. Regardless of adjusting for confounders such as age, gender, and NIHSS score, there was no significant difference in the risk of MHR or monocyte count within 90 days of hospitalization. The conclusion indicates that the combination of Cmmi-MHR and thromboelastography parameters provides a new perspective and method for the diagnosis and treatment of cerebral infarction, and provides important support for personalized treatment and management of cerebral infarction.


Assuntos
Infarto Cerebral , Tromboelastografia , Humanos , Tromboelastografia/métodos , Infarto Cerebral/diagnóstico por imagem , Infarto Cerebral/sangue , Infarto Cerebral/mortalidade , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Valor Preditivo dos Testes , Estudos Retrospectivos , Doença Aguda , Algoritmos , China/epidemiologia , Idoso de 80 Anos ou mais
7.
BMC Plant Biol ; 23(1): 650, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-38102566

RESUMO

BACKGROUND: The number of grains per panicle is an important factor in determining rice yield. The DST-OsCKX2 module has been demonstrated to regulate panicle development in rice by controlling cytokinin content. However, to date, how the function of DST-OsCKX2 module is regulated during panicle development remains obscure. RESULT: In this study, the ABNORMAL PANICLE 1 (ABP1), a severely allele of FRIZZY PANICLE (FZP), exhibits abnormal spikelets morphology. We show that FZP can repress the expression of DST via directly binding to its promotor. Consistently, the expression level of OsCKX2 increased and the cytokinin content decreased in the fzp mutant, suggesting that the FZP acts upstream of the DST-OsCKX2 to maintain cytokinin homeostasis in the inflorescence meristem. CONCLUSIONS: Our results indicate that FZP plays an important role in regulating spikelet development and grain number through mediating cytokinin metabolism.


Assuntos
Oryza , Oryza/metabolismo , Inflorescência/genética , Citocininas/metabolismo , Grão Comestível/metabolismo , Proteínas de Plantas/metabolismo
8.
Int J Med Sci ; 20(3): 346-358, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36860681

RESUMO

Qinggan Huoxue Recipe (QGHXR) is originated from Xiao Chaihu Decotion. Many experimental studies have confirmed that QGHXR can significantly alleviate the symptoms of alcoholic liver disease (ALD), but the detailed mechanism is still unclear. Using traditional Chinese medicine network pharmacology analysis system database and animal experiments, we found that 180 potentially chemical compositions and 618 potential targets were screened from the prescription, which shared 133 signal pathways with ALD. Through animal experiments, it was found that QGHXR could reduce the liver total cholesterol (TC), serum TC, alanine aminotransferase, aspartate aminotransferase of ALD mice, reduce the lipid droplets and inflammatory injury of liver tissue. Meanwhile, it can also increase PTEN, decrease PI3K and AKT mRNA levels. In this study, we obtained the targets and pathways of QGHXR in the treatment of ALD, and preliminatively verified that QGHXR may improve ALD through PTEN/PI3K/AKT signaling pathway.


Assuntos
Hepatopatias Alcoólicas , Fosfatidilinositol 3-Quinases , Animais , Camundongos , Fosfatidilinositol 3-Quinases/genética , Proteínas Proto-Oncogênicas c-akt/genética , Farmacologia em Rede , Hepatopatias Alcoólicas/tratamento farmacológico , Transdução de Sinais
9.
J Biopharm Stat ; : 1-11, 2023 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-37724802

RESUMO

Following good statistical practice, in vivo study investigators allocate animals into two or more treatment groups using a randomization routine to eliminate selection bias and balance known and unknown confounding factors. For some studies, however, randomization at the individual animal level cannot be implemented. For example, for studies that involve co-housed male mice, an animal-level randomization can place unfamiliar mice together in the same cage, which can trigger fighting. To meet the ethical obligations to enhance the welfare of an animal used in science, the experimental procedures are, therefore, often modified, and male mice, possibly from the same brood, may be housed together. It follows that animal allocation into groups must proceed at the whole-cage level. Given the small sample sizes in animal studies, controlling baseline variables can be quite challenging. The difficulty greatly increases with a whole-cage randomization restriction. When the number of animals per cage or the treatment group sizes are unequal, there is no algorithm in the literature to perform the task. We propose a novel, fast, and reliable algorithm to provide a whole-cage randomization that balances one or more baseline variables across groups. The algorithm was applied to a realistic example dataset.

10.
Molecules ; 28(7)2023 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-37049673

RESUMO

One new dibenzyltyrolactone lignan dysoslignan A (1), three new arylnaphthalide lignans dysoslignan B-C (2-4), along with fourteen known metabolites (5-18), were isolated from the roots and rhizomes of Dysosma versipellis. Their structures and stereochemistry were determined from analysis of NMR spectroscopic and circular dichroism (CD) data. Compound 2 represents the first report of naturally occurring arylnaphthalide lignan triglycoside. The cytotoxic activities of all isolated compounds were evaluated against A-549 and SMMC-7721 cell lines. Compounds 7-10 and 14-16 were more toxic than cisplatin in two tumor cell lines. This investigation clarifies the potential effective substance basis of D. versipellis in tumor treatment.


Assuntos
Berberidaceae , Lignanas , Raízes de Plantas , Rizoma , Células A549 , Antineoplásicos/efeitos adversos , Antineoplásicos/toxicidade , Berberidaceae/química , Berberidaceae/metabolismo , Dicroísmo Circular , Cisplatino/efeitos adversos , Cisplatino/toxicidade , Lignanas/química , Lignanas/isolamento & purificação , Lignanas/metabolismo , Lignanas/toxicidade , Espectroscopia de Ressonância Magnética , Neoplasias/tratamento farmacológico , Raízes de Plantas/química , Raízes de Plantas/metabolismo , Rizoma/química , Rizoma/metabolismo , Linhagem Celular Tumoral
11.
Eur J Neurosci ; 56(2): 3991-4008, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35560852

RESUMO

Spinal cord injury (SCI) damages sensory systems, producing chronic neuropathic pain that is resistant to medical treatment. The specific mechanisms underlying SCI-induced neuropathic pain (SCI-NP) remain unclear, and protein biomarkers have not yet been integrated into diagnostic screening. To better understand the host molecular pathways involved in SCI-NP, we used the bioinformatics method, the PubMed database and bioinformatics methods to identify target genes and their associated pathways. We reviewed 2504 articles on the regulation of SCI-NP and used the text mining of PubMed database abstracts to determine associations among 12 pathways and networks. Based on this method, we identified two central genes in SCI-NP: interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α). Adult male Sprague-Dawley rats were used to build the SCI-NP models. The threshold for paw withdrawal was significantly reduced in the SCI group, and TLR4 was activated in microglia after SCI. Enzyme-linked immunosorbent assay(ELISA) analysis of TNF-α and IL-6 levels was significantly higher in the SCI group than in the sham group. Western blot showed that expressions of the TLR4/MyD88/NF-κB inflammatory pathway protein increased dramatically in the SCI group. Using the TLR4 inhibitor TAK-242, the pain threshold and expressions of inflammatory factors and proteins of the proteins of the inflammatory signal pathway were reversed, TLR4 in microglia was suppressed, suggesting that SCI-NP was related to neuroinflammation mediated by the TLR4 signalling pathway. In conclusion, we found that TNF-α and IL-6 were the neuroinflammation-related genes involved in SCI-NP that can be alleviated by inhibiting the inflammatory pathway upstream of the TLR4/MyD88/NF-κB inflammatory pathway.


Assuntos
Neuralgia , Traumatismos da Medula Espinal , Animais , Interleucina-6/genética , Interleucina-6/metabolismo , Masculino , Fator 88 de Diferenciação Mieloide/metabolismo , NF-kappa B/metabolismo , Neuralgia/genética , Neuralgia/metabolismo , Ratos , Ratos Sprague-Dawley , Medula Espinal/metabolismo , Traumatismos da Medula Espinal/complicações , Traumatismos da Medula Espinal/genética , Traumatismos da Medula Espinal/metabolismo , Receptor 4 Toll-Like/genética , Receptor 4 Toll-Like/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
12.
J Neuroinflammation ; 19(1): 51, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35177106

RESUMO

BACKGROUND: Traumatic brain injury (TBI) is a kind of acquired brain injury, which is caused by external mechanical forces. Moreover, the neuroprotective role of sevoflurane (Sevo) has been identified in TBI. Therefore, this research was conducted to figure out the mechanism of Sevo in TBI via FGF2. METHODS: The key factors of neuroprotective effects of Sevo in TBI rats were predicted by bioinformatics analysis. A TBI model was induced on rats that then inhaled Sevo for 1 h and grouped via lentivirus injection. Modified Neurological Severity Score was adopted to evaluate neuronal damage in rats, followed by motor function and brain water content measurement. FGF2, EZH2, and HES1 expression in brain tissues was evaluated by immunofluorescence staining, and expression of related genes and autophagy factors by RT-qPCR and Western blot analysis. Methylation-specific PCR was performed to assess HES1 promoter methylation level, and ChIP assay to detect the enrichment of EZH2 in the HES1 promoter. Neuronal damage was assessed by cell immunofluorescence staining, and neuronal apoptosis by Nissl staining, TUNEL staining, and flow cytometry. RESULTS: Sevo diminished brain edema, improved neurological scores, and decreased neuronal apoptosis and autophagy in TBI rats. Sevo preconditioning could upregulate FGF2 that elevated EZH2 expression, and EZH2 bound to the HES1 promoter to downregulate HES1 in TBI rats. Also, FGF2 or EZH2 overexpression or HES silencing decreased brain edema, neurological deficits, and neuronal autophagy and apoptosis in Sevo-treated TBI rats. CONCLUSIONS: Our results provided a novel insight to the neuroprotective mechanism of Sevo in TBI rats by downregulating HES1 via FGF2/EZH2 axis activation.


Assuntos
Lesões Encefálicas Traumáticas , Fármacos Neuroprotetores , Animais , Apoptose , Lesões Encefálicas Traumáticas/metabolismo , Fator 2 de Crescimento de Fibroblastos , Neuroproteção , Fármacos Neuroprotetores/farmacologia , Fármacos Neuroprotetores/uso terapêutico , Ratos , Ratos Sprague-Dawley , Sevoflurano/farmacologia , Sevoflurano/uso terapêutico
13.
Metab Eng ; 69: 175-187, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34838998

RESUMO

Colorectal cancer (CRC) is a major cause of morbidity and mortality in the United States. Tumor-stromal metabolic crosstalk in the tumor microenvironment promotes CRC development and progression, but exactly how stromal cells, in particular cancer-associated fibroblasts (CAFs), affect the metabolism of tumor cells remains unknown. Here we take a data-driven approach to investigate the metabolic interactions between CRC cells and CAFs, integrating constraint-based modeling and metabolomic profiling. Using metabolomics data, we perform unsteady-state parsimonious flux balance analysis to infer flux distributions for central carbon metabolism in CRC cells treated with or without CAF-conditioned media. We find that CAFs reprogram CRC metabolism through stimulation of glycolysis, the oxidative arm of the pentose phosphate pathway (PPP), and glutaminolysis, as well as inhibition of the tricarboxylic acid cycle. To identify potential therapeutic targets, we simulate enzyme knockouts and find that CAF-treated CRC cells are especially sensitive to inhibitions of hexokinase and glucose-6-phosphate, the rate limiting steps of glycolysis and oxidative PPP. Our work gives mechanistic insights into the metabolic interactions between CRC cells and CAFs and provides a framework for testing hypotheses towards CRC-targeted therapies.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Colorretais , Fibroblastos Associados a Câncer/metabolismo , Fibroblastos Associados a Câncer/patologia , Cromatografia Líquida , Neoplasias Colorretais/genética , Neoplasias Colorretais/metabolismo , Neoplasias Colorretais/patologia , Humanos , Metabolômica , Espectrometria de Massas em Tandem , Microambiente Tumoral
14.
Ann Neurol ; 89(1): 74-90, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32996158

RESUMO

OBJECTIVE: Parkinson disease (PD) has useful symptomatic treatments that do not slow the neurodegenerative process, and no significant disease-modifying treatments are approved. A key therapeutic target in PD is α-synuclein (αS), which is both genetically implicated and accumulates in Lewy bodies rich in vesicles and other lipid membranes. Reestablishing αS homeostasis is a central goal in PD. Based on previous lipidomic analyses, we conducted a mouse trial of a stearoyl-coenzyme A desaturase (SCD) inhibitor ("5b") that prevented αS-positive vesicular inclusions and cytotoxicity in cultured human neurons. METHODS: Oral dosing and brain activity of 5b were established in nontransgenic mice. 5b in drinking water was given to mice expressing wild-type human αS (WT) or an amplified familial PD αS mutation (E35K + E46K + E61K ["3K"]) beginning near the onset of nigral and cortical neurodegeneration and the robust PD-like motor syndrome in 3K. Motor phenotypes, brain cytopathology, and SCD-related lipid changes were quantified in 5b- versus placebo-treated mice. Outcomes were compared to effects of crossing 3K to SCD1-/- mice. RESULTS: 5b treatment reduced αS hyperphosphorylation in E46K-expressing human neurons, in 3K neural cultures, and in both WT and 3K αS mice. 5b prevented subtle gait deficits in WT αS mice and the PD-like resting tremor and progressive motor decline of 3K αS mice. 5b also increased αS tetramers and reduced proteinase K-resistant lipid-rich aggregates. Similar benefits accrued from genetically deleting 1 SCD allele, providing target validation. INTERPRETATION: Prolonged reduction of brain SCD activity prevented PD-like neuropathology in multiple PD models. Thus, an orally available SCD inhibitor potently ameliorates PD phenotypes, positioning this approach to treat human α-synucleinopathies. ANN NEUROL 2021;89:74-90.


Assuntos
Doença de Parkinson/prevenção & controle , alfa-Sinucleína/genética , Animais , Encéfalo/patologia , Humanos , Corpos de Lewy/patologia , Camundongos Transgênicos , Neurônios/metabolismo , Doença de Parkinson/genética , Fenótipo , alfa-Sinucleína/metabolismo
15.
Opt Express ; 30(2): 1925-1936, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209344

RESUMO

We measured the spin noise spectroscopy (SNS) of rubidium atomic ensemble with two different kinds of atomic vapor cells (filled with buffer gas or coated with paraffin film on the inner wall) and demonstrated the enhancement of the signal-to-noise ratio (SNR) by using polarization squeezed state (PSS) of 795-nm light field with Stokes operator S Λ 2 squeezed. The PSS is prepared by locking the relative phase between the squeezed vacuum state of light obtained with a sub-threshold optical parametric oscillator and the orthogonally polarized local oscillator beam by means of the quantum noise lock. Under the same conditions, the PSS can be employed not only to improve the SNR, but also to keep the full width at half maximum (FWHM) of SNS, compared with the case of using the polarization coherent state (PCS), enhancement of SNR is positively correlated with the squeezing level of the PSS. With increasing probe laser power and atomic number density, the SNR and FWHM of SNS will increase correspondingly. With the help of the PSS of the Stokes operator S Λ 2, quantum improvements of both the SNR and FWHM of SNS signal has been demonstrated by controlling optical power of polarization squeezed light beam or atomic number density in our experiments.

16.
Cell Mol Neurobiol ; 42(3): 621-646, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33125600

RESUMO

Hemorrhagic transformation (HT) is a common complication after thrombolysis with recombinant tissue-type plasminogen activator (rt-PA) in ischemic stroke. In this article, recent research progress of HT in vivo and in vitro studies was reviewed. We have discussed new potential mechanisms and possible experimental models of HT development, as well as possible biomarkers and treatment methods. Meanwhile, we compared and analyzed rodent models, large animal models and in vitro BBB models of HT, and the limitations of these models were discussed. The molecular mechanism of HT was investigated in terms of BBB disruption, rt-PA neurotoxicity and the effect of neuroinflammation, matrix metalloproteinases, reactive oxygen species. The clinical features to predict HT were represented including blood biomarkers and clinical factors. Recent progress in neuroprotective strategies to improve HT after stroke treated with rt-PA is outlined. Further efforts need to be made to reduce the risk of HT after rt-PA therapy and improve the clinical prognosis of patients with ischemic stroke.


Assuntos
Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Animais , Biomarcadores , Isquemia Encefálica/complicações , Isquemia Encefálica/tratamento farmacológico , Humanos , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Ativador de Plasminogênio Tecidual/efeitos adversos
17.
Med Sci Monit ; 28: e936953, 2022 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-35869616

RESUMO

BACKGROUND This study aimed to investigate the optimum time to reintroduce the original antiplatelet drugs after upper gastrointestinal hemorrhage in patients as secondary prevention for cardiovascular and cerebrovascular diseases. MATERIAL AND METHODS After the upper gastrointestinal bleeding stopped, patients were randomly divided according to the oral antiplatelet drugs administered. The aspirin group was further divided into 3-day and 7-day aspirin groups. The patients who took aspirin and clopidogrel were randomly divided into 3 groups: 0-day aspirin+3-day clopidogrel; 0-day aspirin+7-day clopidogrel; and 3-day aspirin+7-day clopidogrel. The recovery time, rebleeding rate, incidence of cardiovascular and cerebrovascular events, and death were observed. RESULTS The 3-day aspirin group had more rebleeding, reduced risk of cardiovascular and cerebrovascular events, and a similar mortality rate compared to the other groups. In the aspirin+clopidogrel group, the 0-day aspirin+3-day clopidogrel group had the highest rebleeding rate and the lowest risk of cardiovascular and cerebrovascular events. The 3-day aspirin+7-day clopidogrel group had the highest risk of cardiovascular and cerebrovascular events and increased hospitalization time. The risk of rebleeding and cardiovascular and cerebrovascular events was lower in the 0-day aspirin+7-day clopidogrel group, and the overall mortality rate was the lowest in this group. CONCLUSIONS In patients receiving only aspirin, this drug should be reintroduced as soon as possible after peptic ulcer hemorrhage. Aspirin and clopidogrel are dual antiplatelet drugs used for the secondary prevention of cardiovascular diseases. In patients under dual-drug therapy, aspirin should not be stopped, while clopidogrel should be restarted in about 7 days.


Assuntos
Inibidores da Agregação Plaquetária , Ticlopidina , Aspirina/efeitos adversos , Clopidogrel/uso terapêutico , Quimioterapia Combinada , Hemorragia Gastrointestinal/tratamento farmacológico , Humanos , Inibidores da Agregação Plaquetária/efeitos adversos , Ticlopidina/uso terapêutico
18.
Sensors (Basel) ; 22(19)2022 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-36236696

RESUMO

A free-induction-decay (FID) type optically-pumped rubidium atomic magnetometer driven by a radio-frequency (RF) magnetic field is presented in this paper. Influences of parameters, such as the temperature of rubidium vapor cell, the power of pump beam, and the strength of RF magnetic field and static magnetic field on the amplitude and the full width at half maximum (FWHM) of the FID signal, have been investigated in the time domain and frequency domain. At the same time, the sensitivities of the magnetometer for the single-pass and the triple-pass probe beam cases have been compared by changing the optical path of the interaction between probe beam and atomic ensemble. Compared with the sensitivity of ∼21.2 pT/Hz1/2 in the case of the single-pass probe beam, the amplitude of FID signal in the case of the triple-pass probe beam has been significantly enhanced, and the sensitivity has been improved to ∼13.4 pT/Hz1/2. The research in this paper provids a reference for the subsequent study of influence of different buffer gas pressure on the FWHM and also a foundation for further improving the sensitivity of FID rubidium atomic magnetometer by employing a polarization-squeezed light as probe beam, to achieve a sensitivity beyond the photo-shot-noise level.

19.
J Environ Manage ; 321: 115952, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35985270

RESUMO

Organic micropollutants (OMPs) in water resources are a growing threat to aquatic ecosystems and human health. Efficient removal of polar OMPs is very challenging because of their high hydrophility. Synthesizing novel adsorbent capable of high-efficiently removing hydrophilic and hydrophobic micropollutants is highly desirable for water remediation. Here, using natural proanthocyanidin as building units, a novel hydroxyl-functional porous organic framework (denoted as PC-POF) with amphiphilic feature was synthesized through facile azo coupling reaction. Five sulfonamide antibiotics were selected as model OMPs for adsorption study. Adsorption experiments demonstrated a more rapid and efficient sulfonamides capture ability of the PC-POF than that of the most reported adsorbents due to strong hydrogen bonding, π stacking and electrostatic interactions. The PC-POF can be easily recovered and reused at least 5 times without obvious decline in adsorption performance. Moreover, experiments conducted at environmentally relevant concentrations (µg L-1) further confirmed a notable adsorption performance of the PC-POF even when the sulfonamides solution was rapidly passed through the PC-POF packed column. The PC-POF also showed good adsorption performance for other micropollutants like neonicotinoid insecticides, nitroimidazole antibiotics and triazine herbicides, indicating a promising prospect. This work provides a new strategy to construct amphiphilic adsorbent by using renewable resources for pollutants removal.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Adsorção , Antibacterianos , Ecossistema , Humanos , Radical Hidroxila , Porosidade , Sulfonamidas , Água/química , Poluentes Químicos da Água/química , Purificação da Água/métodos
20.
Molecules ; 27(4)2022 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-35208972

RESUMO

Three new polyhydroxylated oleanane triterpenoids, cissatriterpenoid A-C (1-3), along with one known analogue (4), were isolated from the whole plant of Cissampelos pareira var. hirsuta. Their chemical structures were elucidated by extensive spectroscopic data (IR, HR-ESI-MS, 1H-NMR, 13C-NMR, DEPT, 1H-1H COSY, HSQC, HMBC, NOESY) and the microhydrolysis method. The isolation of compounds 1-4 represents the first report of polyhydroxylated oleanane triterpenoids from the family Menispermaceae. All isolated compounds were evaluated for their cytotoxicity against five human cancer cell lines, and the inhibitory activity against NO release in LPS-induced RAW 264.7 cells. Compound 3 showed the most potent cytotoxic activities against the A549, SMMC-7721, MCF-7, and SW480 cell lines, with IC50 values of 17.55, 34.74, 19.77, and 30.39 µM, respectively, whereas three remaining ones were found to be inactive. The preliminary structure-activity relationship analysis indicated that the γ-lactone ring at C-22 and C-29, and the olefinic bond at C-12 and C-13 were structurally required for the cytotoxicity of polyhydroxylated oleanane triterpenoids against these four cell lines. Based on lipid-water partition coefficients, compound 3 is less lipophilic than 1 and 4, which agrees with their cytotoxic activities. This confirms the potential of C. pareira var. hirsuta in the tumor treatment.


Assuntos
Antineoplásicos Fitogênicos , Cissampelos/química , Citotoxinas , Neoplasias/tratamento farmacológico , Ácido Oleanólico , Animais , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Citotoxinas/química , Citotoxinas/isolamento & purificação , Citotoxinas/farmacologia , Humanos , Células MCF-7 , Camundongos , Neoplasias/metabolismo , Ácido Oleanólico/química , Ácido Oleanólico/isolamento & purificação , Ácido Oleanólico/farmacologia , Células RAW 264.7
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA