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1.
J Nat Prod ; 87(1): 38-49, 2024 01 26.
Artigo em Inglês | MEDLINE | ID: mdl-38207331

RESUMO

Physalis angulata var. villosa is a plant possessing abundant withanolides, but in-depth research is lacking. In our ongoing study of P. angulata var. villosa, 15 previously undescribed withanolides (1-15), along with 21 known analogs (16-36), were isolated from the whole plant. The structures of the withanolides (1-15) were elucidated based on analysis of their 1D and 2D NMR, HRESIMS, and ECD data. Additionally, the application of γ-gauche effects with the help of ROESY correlations led to the formulation of empirical rules for withanolides with 14-OH/15-OAc to rapidly determine the 14-OH orientations, making it possible to propose configurational revisions of 19 previously reported analogs (1'-19'). Withanolides 1, 4-6, and 10 showed potent cytotoxic activities against three human cancer cell lines (HCT-116, MDA-MB-231, and A549).


Assuntos
Antineoplásicos Fitogênicos , Physalis , Vitanolídeos , Humanos , Vitanolídeos/farmacologia , Vitanolídeos/química , Physalis/química , Extratos Vegetais/química , Antineoplásicos Fitogênicos/farmacologia , Antineoplásicos Fitogênicos/química , Linhagem Celular , Estrutura Molecular
2.
Mol Plant Microbe Interact ; 35(8): 659-671, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-36043906

RESUMO

Bacillus spp. are known for their ability to control plant diseases; however, the mechanism of disease control by Bacillus spp. is still unclear. Previously, bacterial organic acids have been implicated in the process of disease suppression. We extracted the total organic acid from Bacillus cereus AR156 culture filtrate and identified oxalic acid (OA) as the programmed cell death-inducing factor. OA strongly suppressed the lesion caused by Botrytis cinerea without significant antagonism against the fungus. Low concentration of OA produced by Bacillus spp. inhibited cell death caused by high concentrations of OA in a concentration- and time-dependent manner. Pretreatment with a low concentration of OA led to higher accumulation of active oxygen-scavenging enzymes in tomato leaves and provoked the expression of defense-related genes. The activation of gene expression relied on the jasmonic acid (JA) signaling pathway but not the salicylic acid (SA) pathway. The disease suppression capacity of OA was confirmed on wild-type tomato and its SA accumulation-deficient line, while the control effect was diminished in JA synthesis-deficient mutant, suggesting that the OA-triggered resistance relied on JA and ethylene (ET) signaling transduction. OA secretion ability was widely distributed among the tested Bacillus strains and the final environmental OA concentration was under strict regulation by a pH-sensitive degradation mechanism. This study provides the first systematic analysis on the role of low-concentration OA secreted and maintained by Bacillus spp. in suppression of gray mold disease and determines the dependence of OA-mediated resistance on the JA/ET signaling pathway. [Formula: see text] The author(s) have dedicated the work to the public domain under the Creative Commons CC0 "No Rights Reserved" license by waiving all of his or her rights to the work worldwide under copyright law, including all related and neighboring rights, to the extent allowed by law, 2022.


Assuntos
Bacillus , Solanum lycopersicum , Botrytis/fisiologia , Ciclopentanos/metabolismo , Regulação da Expressão Gênica de Plantas , Solanum lycopersicum/genética , Ácido Oxálico , Oxilipinas/metabolismo , Doenças das Plantas/microbiologia , Ácido Salicílico/metabolismo
3.
Molecules ; 27(18)2022 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-36144749

RESUMO

Essential oils (EOs) have been proposed as an alternative to conventional pesticides to inhibit fungal pathogens. However, the application of EOs is considerably limited due to their highly volatile nature and unpredictable effects on other microbes. In our study, the composition of bacterial and fungal communities from the rhizosphere soil of P. notoginseng under four treatment levels of Alpinia officinarum Hance EO was characterized over several growth stages. Leaf weight varied dramatically among the four EO treatment levels after four months of growth, and the disease index at a low concentration (0.14 mg/g) of EO addition was the lowest among the P. notoginseng growth stages. The content of monomeric saponins was elevated when EO was added. Bacterial and fungal diversity in the absence of plants showed a decreasing trend with increasing levels of EO. Bacterial diversity recovery was more correlated with plant growth than was fungal diversity recovery. Compared with the control (no EO addition), a low concentration of EO significantly accumulated Actinomycota, including Acidothermus, Blastococcus, Catenulispora, Conexibacter, Rhodococcus, and Sinomonas, after one month of plant-microbial interaction. Overall, the results showed that both the plant growth stage and EOs drive changes in the microbial community composition in the rhizosphere of P. notoginseng. Plant development status had a stronger influence on bacterial diversity than on fungal diversity. EO had a more significant effect on fungal community composition, increasing the dominance of Ascomycota when EO concentration was increased. Under the interaction of P. notoginseng growth and EO, a large number of bacterial genera that have been described as plant growth-promoting rhizobacteria (PGPR) responded positively to low concentrations of EO application, suggesting that EO may recruit beneficial microbes in the root zone to cope with pathogens and reduce root rot disease. These results offer novel insights into the relationship between EO application, altered microbial communities in the plant roots, plant growth stage, and disease occurrence.


Assuntos
Alpinia , Ascomicetos , Microbiota , Óleos Voláteis , Panax notoginseng , Praguicidas , Saponinas , Bactérias , Óleos Voláteis/farmacologia , Panax notoginseng/microbiologia , Desenvolvimento Vegetal , Raízes de Plantas , Rizosfera , Solo , Microbiologia do Solo
4.
BMC Infect Dis ; 19(1): 145, 2019 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-30755175

RESUMO

BACKGROUND: To determine the epidemiology and risk factors for nosocomial infection (NI) in the Respiratory Intensive Care Unit (RICU) of a teaching hospital in Northwest China. METHODS: An observational, prospective surveillance was conducted in the RICU from 2013 to 2015. The overall infection rate, distribution of infection sites, device-associated infections and pathogen in the RICU were investigated. Then, the logistic regression analysis was used to test the risk factors for RICU infection. RESULTS: In this study, 102 out of 1347 patients experienced NI. Among them, 87 were device-associated infection. The overall prevalence of NI was 7.57% with varied rates from 7.19 to 7.73% over the 3 years. The lower respiratory tract (43.1%), urinary tract (26.5%) and bloodstream (20.6%) infections accounted for the majority of infections. The device-associated infection rates of urinary catheter, central catheter and ventilator were 9.8, 7.4 and 7.4 per 1000 days, respectively.The most frequently isolated pathogens were Staphylococcus aureus (20.9%), Klebsiella pneumoniae (16.4%) and Pseudomonas aeruginosa (10.7%). Multivariate analysis showed that the categories D or E of Average Severity of Illness Score (ASIS), length of stay (10-30, 30-60, ≥60 days), immunosuppressive therapy and ventilator use are the independent risk factors for RICU infection with an adjusted odds ratio (OR) of 1.65 (95% CI: 1.15~2.37), 5.22 (95% CI: 2.63~10.38)), 2.32 (95% CI: 1.19~4.65), 8.93 (95% CI: 3.17~21.23), 31.25 (95% CI: 11.80~63.65)) and 2.70 (95% CI: 1.33~5.35), respectively. CONCLUSION: A relatively low and stable rate of NI was observed in our RICU through year 2013-2015. The ASIS-D、E, stay ≥10 days, immunosuppressive therapy and ventilator use are the independent risk factors for RICU infection.


Assuntos
Infecção Hospitalar/epidemiologia , Hospitais de Ensino , Unidades de Terapia Intensiva , Cateterismo Venoso Central/efeitos adversos , China/epidemiologia , Infecção Hospitalar/etiologia , Infecção Hospitalar/microbiologia , Feminino , Humanos , Incidência , Klebsiella pneumoniae , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Pseudomonas aeruginosa , Fatores de Risco , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/etiologia , Staphylococcus aureus , Cateteres Urinários/efeitos adversos , Ventiladores Mecânicos/efeitos adversos
5.
Biochem Biophys Res Commun ; 487(4): 801-806, 2017 06 10.
Artigo em Inglês | MEDLINE | ID: mdl-28450109

RESUMO

T-type calcium channels are prominently expressed in primary nociceptive fibers and well characterized in pain processes. Although itch and pain share many similarities including primary sensory fibers, the function of T-type calcium channels on acute itch has not been explored. We investigated whether T-type calcium channels expressed within primary sensory fibers of mouse skin, especially Cav3.2 subtype, involve in chloroquine-, endothelin-1- and histamine-evoked acute itch using pharmacological, neuronal imaging and behavioral analyses. We found that pre-locally blocking three subtypes of T-type calcium channels in the peripheral afferents of skins, yielded an inhibition in acute itch or pain behaviors, while selectively blocking the Cav3.2 channel in the skin peripheral afferents only inhibited acute pain but not acute itch. These results suggest that T-type Cav3.1 or Cav3.3, but not Cav3.2 channel, have an important role in acute itch processing, and their distinctive roles in modulating acute itch are worthy of further investigation.


Assuntos
Canais de Cálcio Tipo T/metabolismo , Neurônios Aferentes/metabolismo , Prurido/metabolismo , Pele/metabolismo , Animais , Masculino , Mibefradil/farmacologia , Camundongos , Camundongos Endogâmicos C57BL
6.
Chin Med Sci J ; 30(3): 135-42, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26564411

RESUMO

OBJECTIVE: To investigate the effect of propofol on brain regions at different sedation levels and the association between changes in brain region activity and loss of consciousness using blood oxygen level-dependent functional magnetic resonance imaging (BOLD-fMRI) and bispectral index (BIS) monitoring. METHODS: Forty-eight participants were enrolled at Peking Union Medical College Hospital from October 2011 to March 2012 and randomly assigned to a mild or a deep sedation group using computer- generated random numbers. Preliminary tests were performed a week prior to scanning to determine target effect site concentrations based on BIS and concomitant Observer's Assessment of Alertness/Sedation scores while under propofol. Within one week of the preliminary tests where propofol dose-response was established, BOLD-fMRI was conducted to examine brain activation with the subject awake, and with propofol infusion at the sedation level. RESULTS: Mild propofol sedation inhibited left inferior parietal lobe activation. Deep sedation inhibited activation of the left insula, left superior temporal gyrus, and right middle temporal gyrus. Compared with mild sedation, deep propofol sedation inhibited activation of the left thalamus, precentral gyrus, anterior cingulate, and right basal nuclei. CONCLUSION: Mild and deep propofol sedation are associated with inhibition of different brain regions, possibly explaining differences in the respective loss of consciousness processes.


Assuntos
Encéfalo/efeitos dos fármacos , Hipnóticos e Sedativos/farmacologia , Propofol/farmacologia , Adulto , Monitores de Consciência , Sedação Profunda , Relação Dose-Resposta a Droga , Humanos , Masculino
7.
Soft Matter ; 10(48): 9651-6, 2014 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-25366572

RESUMO

An anionic self-folding deep cavitand is capable of immobilizing unmodified proteins and enzymes at a supported lipid bilayer interface, providing a simple, soft bioreactive surface that allows enzymatic function under mild conditions. The adhesion is based on complementary charge interactions, and the hosts are capable of binding enzymes such as trypsin at the bilayer interface: the catalytic activity is retained upon adhesion, allowing selective reactions to be performed at the membrane surface.


Assuntos
Éteres Cíclicos/química , Bicamadas Lipídicas/química , Proteínas/química , Resorcinóis/química , Sequência de Aminoácidos , Ânions/química , Dados de Sequência Molecular , Ligação Proteica , Proteínas/metabolismo , Eletricidade Estática
8.
BMJ Open ; 14(6): e083956, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38925689

RESUMO

OBJECTIVE: To provide an initial understanding of problems and potential solution strategies for part-time clinical pharmacist work in China, and provide references for the training of part-time clinical pharmacists. METHODS: The study was conducted in a tertiary teaching hospital in China, and the project lasted 6 months. Phenomenological methods were used to guide the research design. Research data were obtained by conducting one-to-one semistructured interviews with part-time clinical pharmacists, and interview data were coded and analysed through thematic analysis. RESULTS: A total of 21 pharmacists were interviewed in a semistructured manner, and the results showed that following problems exist in the work of part-time clinical pharmacists: the existing professional knowledge is not adequate to meet the demands of clinical service; the career orientation of part-time clinical pharmacists is not clear; lack of professional self-confidence in clinical pharmacy practice; there is no suitable entry point to carry out pharmacy service work; it is difficult to communicate effectively, and for in addition, 17 potential solution strategies are proposed for the current problems, which can provide reference for the development of part-time clinical pharmacists' work. CONCLUSIONS: The work performed by part-time clinical pharmacists is currently immature and the strategies derived from this study may serve as potential solutions to resolve the part-time clinical pharmacy practice challenges.


Assuntos
Farmacêuticos , Serviço de Farmácia Hospitalar , Pesquisa Qualitativa , Centros de Atenção Terciária , Humanos , China , Serviço de Farmácia Hospitalar/organização & administração , Masculino , Feminino , Adulto , Entrevistas como Assunto , Papel Profissional , Atitude do Pessoal de Saúde , Hospitais de Ensino
9.
Transl Oncol ; 49: 102083, 2024 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-39128259

RESUMO

BACKGROUND: γ-Glutamylcyclotransferase (GGCT), an enzyme crucial in glutathione metabolism, has emerged as a participant in tumorigenesis. The present study is designed to elucidate the biological role and molecular mechanisms underlying GGCT in glioma. METHODS: Gene Expression Profiling Interactive Analysis (GEPIA), Chinese Glioma Genome Atlas (CGGA), and PrognoScan online databases were utilized to examine the expressions and clinical prognosis of GGCT and REST in glioma. Cell Counting Kit-8 (CCK-8), Transwell, Wound healing, and Flow cytometric assays, and RNA-sequencing analysis were employed to uncover the molecular role of GGCT and REST. Prediction of Differentially expressed microRNA (DE-miRNAs) and miRNAs targeting GGCT 3' Untranslated Region (UTR) was performed using miRanda online datasets. Finally, Real time-quantitative Polymerase Chain Reaction (RT-qPCR), western blot and dual luciferase reporter gene activity analysis were employed to confirm a positive feedback loop involving GGCT/REST/miR-34a-5p in glioma cells. RESULTS: High expression of GGCT was correlated with poor prognosis in glioma. GGCT silencing demonstrated inhibitory effects on the proliferation, migration, and induction of apoptosis in T98G and U251 cells. Mechanistically, GGCT downregulated REST expression and modulated cancer-associated pathways in glioma cells. High expression of REST was associated with poor prognosis in glioma. In vitro and in vivo experiments showed that REST overexpression restored the repression of proliferation, invasion, migration, and xenograft tumor formation induced by GGCT knockdown. Furthermore, the study uncovered that REST inhibited miR-34a-5p mRNA expression, and miR-34a-5p suppressed GGCT expression by targeting its 3'UTR, forming a positive regulatory loop in glioma. Notably, the inhibitor of miR-34a-5p restored the role of REST silencing in decreasing GGCT expression in glioma cells. CONCLUSIONS: GGCT/REST/miR-34a-5p axis holds promising potential as a therapeutic target, offering a potential breakthrough in the treatment of glioma.

10.
Heliyon ; 10(5): e27082, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38455561

RESUMO

Introduction: Innate and acquired chemoresistance in colorectal cancer (CRC) often results in 5-fluorouracil (5-FU) treatment failure. This study aimed to investigate the potential of Jianpi Jiedu (JPJD) decoction to reverse 5-FU resistance in CRC and clarify its potential mechanism of action. Methods: The CCK-8 assay was employed to assess cell activity. Flow cytometry was employed to assess various parameters including cell apoptosis, cell cycle distribution, P-glycoprotein (P-gp) activity, reactive oxygen species levels, and lipid peroxidation. Metabolomics analysis was conducted to identify differentially expressed metabolites. Western blotting was utilized for protein expression analysis. Results: In this study, we demonstrated that the combined JPJD and 5-FU treatment reversed 5-FU resistance in HCT8/5-FU cells, inducing cell apoptosis, causing G2/M-phase cell cycle arrest, and reducing P-gp protein expression and activity. Metabolomics analysis revealed ferroptosis as a key pathway in the development of 5-FU resistance. Furthermore, the combination treatment reversed drug resistance primarily by impacting ferroptosis and triggering critical ferroptosis events through the suppression of the cystine/glutamate transporter (xCT)/glutathione (GSH)/glutathione peroxidase (GPX4) axis. Conclusion: JPJD decoction primarily suppressed the xCT/GSH/GPX4 axis to trigger ferroptosis, thereby effectively reversing 5-FU resistance in colorectal cancer (CRC).

11.
Front Neurosci ; 18: 1373136, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38638694

RESUMO

Introduction: Many studies have shown that the functional adaptation of immigrants to high-altitude is closely related to oxygen transport, inflammatory response and autonomic nervous system. However, it remains unclear how human attention changes in response to hypoxia-induced neurophysiological activity during high-altitude exposure. Methods: In the present study, we analyzed the relationship between hypoxic-induced neurophysiological responses and attention networks in 116 immigrants (3,680 m) using an attention network test to simultaneously record electroencephalogram and electrocardiogram in combination with specific routine blood markers. Results: Our analysis revealed that red blood cells exert an indirect influence on the three attention networks, mediated through inflammatory processes and heart rate variability. Discussion: The present study provides experimental evidence for the role of a neuroimmune pathway in determining human attention performance at high- altitude. Our findings have implications for understanding the complex interactions between physiological and neurocognitive processes in immigrants adapting to hypoxic environments.

12.
Hum Vaccin Immunother ; 20(1): 2323861, 2024 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-38497584

RESUMO

Immunotherapy, particularly immune checkpoint inhibitor (ICIs) therapy, stands as an innovative therapeutic approach currently garnering substantial attention in cancer treatment. It has become a focal point of numerous studies, showcasing significant potential in treating malignancies, including lung cancer and melanoma. The objective of this research is to analyze publications regarding immunotherapy for colorectal cancer (CRC), investigating their attributes and identifying the current areas of interest and cutting-edge advancements. We took into account the publications from 2002 to 2022 included in the Web of Science Core Collection. Bibliometric analysis and visualization were conducted using CiteSpace, VOSviewer, R-bibliometrix, and Microsoft Excel. The quantity of publications associated with this domain has been steadily rising over the years, encompassing 3753 articles and 1498 reviews originating from 573 countries and regions, involving 19,166 institutions, 1011 journals, and 32,301 authors. In this field, China, the United States, and Italy are the main countries that come forward for publishing. The journal with the greatest impact factor is CA-A Cancer Journal for Clinicians. Romain Cohen leads in the number of publications, while Le Dt stands out as the most influential author. The immune microenvironment and immune infiltration are emerging as key hotspots and future research directions in this domain. This research carries out an extensive bibliometric examination of immunotherapy for colorectal cancer, aiding researchers in understanding current focal points, investigating possible avenues for research, and recognizing forthcoming development trends.


Assuntos
Neoplasias Colorretais , Imunoterapia , Humanos , Bibliometria , China , Inibidores de Checkpoint Imunológico , Neoplasias Colorretais/terapia , Microambiente Tumoral
13.
J Cell Mol Med ; 17(11): 1397-409, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24251790

RESUMO

Current JAK2 inhibitors used for myeloproliferative neoplasms (MPN) treatment are not specific enough to selectively suppress aberrant JAK2 signalling and preserve physiological JAK2 signalling. We tested whether combining a JAK2 inhibitor with a series of serine threonine kinase inhibitors, targeting nine signalling pathways and already used in clinical trials, synergized in inhibiting growth of haematopoietic cells expressing mutant and wild-type forms of JAK2 (V617F) or thrombopoietin receptor (W515L). Out of 15 kinase inhibitors, the ZSTK474 phosphatydylinositol-3'-kinase (PI3K) inhibitor molecule showed strong synergic inhibition by Chou and Talalay analysis with JAK2 and JAK2/JAK1 inhibitors. Other pan-class I, but not gamma or delta specific PI3K inhibitors, also synergized with JAK2 inhibitors. Synergy was not observed in Bcr-Abl transformed cells. The best JAK2/JAK1 and PI3K inhibitor combination pair (ruxolitinib and GDC0941) reduces spleen weight in nude mice inoculated with Ba/F3 cells expressing TpoR and JAK2 V617F. It also exerted strong inhibitory effects on erythropoietin-independent erythroid colonies from MPN patients and JAK2 V617F knock-in mice, where at certain doses, a preferential inhibition of JAK2 V617F mutated progenitors was detected. Our data support the use of a combination of JAK2 and pan-class I PI3K inhibitors in the treatment of MPNs.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Janus Quinase 2/antagonistas & inibidores , Transtornos Mieloproliferativos/tratamento farmacológico , Inibidores de Fosfoinositídeo-3 Quinase , Animais , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Ensaios de Seleção de Medicamentos Antitumorais , Sinergismo Farmacológico , Feminino , Técnicas de Introdução de Genes , Neoplasias Hematológicas/tratamento farmacológico , Neoplasias Hematológicas/enzimologia , Humanos , Janus Quinase 2/genética , Janus Quinase 2/metabolismo , Camundongos , Camundongos Nus , Camundongos Transgênicos , Mutação de Sentido Incorreto , Transtornos Mieloproliferativos/enzimologia , Transplante de Neoplasias , Nitrilas , Fosfatidilinositol 3-Quinases/metabolismo , Pirazóis/administração & dosagem , Pirimidinas , Pirrolidinas/administração & dosagem , Transdução de Sinais/efeitos dos fármacos , Sulfonamidas/administração & dosagem , Triazinas/administração & dosagem , Células Tumorais Cultivadas
14.
Physiol Behav ; 268: 114235, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37178854

RESUMO

Many studies have indicated a strong relationship between cardiac and brain activities, both of which are sensitive to high-altitude exposure. This study combined a consciousness access task and electrocardiograms (ECG) to uncover conscious awareness in response to high-altitude exposure and its relation to cardiac activity. When compared with the low-altitude groups, the behavioral results showed that the high-altitude participants shortened the time of access to visual awareness of grating orientation, which was accompanied by a faster heart rate, excluding the influence of pre-stimulus heart rate, extent of cardiac deceleration after presenting the stimulus, and task difficulty. Although there were post-stimulation cardiac deceleration and post-response acceleration at both high and low altitudes, a slight increase in heart rate after stimulation at high altitudes may indicate that participants at high altitudes could quickly readjust their attention to the target stimulus. More importantly, the drift diffusion model (DDM) was used to fit the access time distribution of all participants. These results suggest that shorter time at high altitudes might be due to the lower threshold, suggesting that less evidence in high-altitude participants was required to access visual consciousness. The participants' heart rates also negatively predicted the threshold through a hierarchical drift diffusion modeling (HDDM) regression. These findings imply that individuals with higher heart rates at high altitudes have a greater cognitive burden.


Assuntos
Altitude , Coração , Humanos , Frequência Cardíaca/fisiologia , Eletrocardiografia , Estado de Consciência/fisiologia
15.
Fitoterapia ; 165: 105404, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36572115

RESUMO

Six new alkaloids (1-6) and six known alkaloids (7-12) were obtained from the stems of Sinomenium acutum. Among them, compounds 1-3 and 6 were four N-oxide alkaloids. The structures and absolute configurations of these new alkaloids were elucidated through comprehensive data of 1D and 2D NMR, HRESIMS and ECD spectra. All isolated compounds were evaluated in vitro for their inhibitory activities against nitric oxide (NO) production and inhibitory effects on AChE. Among them, the sinomenine N-oxide (9) was the most potent NO production inhibitor, with an IC50 value of 23.04 µM.


Assuntos
Alcaloides , Medicamentos de Ervas Chinesas , Sinomenium/química , Óxidos , Estrutura Molecular , Alcaloides/farmacologia , Alcaloides/química , Medicamentos de Ervas Chinesas/farmacologia
16.
Neuroscience ; 522: 69-80, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37164304

RESUMO

The psychological effects of long-term exposure to high-altitude environments have attracted great attention. These effects are usually attributed to the diminished cognitive resources due to high-altitude exposure. This study employed electroencephalography (EEG) to investigate the effects of exposure duration on awareness detection tasks. Neither reaction time nor accuracy showed the direct effects of the exposure duration, so did the model indexes obtained from drift diffusion model analysis. However, event-related potentials (ERP) analysis revealed that exposure duration was associated with changes in the visual awareness negativity (VAN) and the late positivity (LP) components, which in turn affected reaction time. Specifically, longer exposure durations were associated with lower VAN and higher LP, resulting in shorter reaction times and greater drift rate. In contrast to previous studies, the reverse relationship between VAN and LP may reflect a compensatory response to the reduced cognitive resources caused by high-altitude exposure. Additionally, increased LP and shorter reaction times with exposure duration may reflect a resistance to the high-altitude environment. We also conducted time-frequency analysis and found that theta power did not vary with exposure duration, suggesting that the reduction in cognitive resources remains stable in these individuals over time. Overall, our study provides new insights into the dynamic effects of high-altitude environments on awareness detection in the presence of reduced cognitive resources.


Assuntos
Altitude , Emigrantes e Imigrantes , Humanos , Tibet , Eletroencefalografia , Potenciais Evocados/fisiologia , Conscientização
17.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 34(3): 222-7, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22776653

RESUMO

OBJECTIVE: To observe the effects of different concentrations of propofol on brain regions activated by mechanical stimuli, and then to investigate the analgesic effect of propofol. METHODS: Twenty healthy male volunteers were randomly divided into two groups: light anesthesia group (group L) (BIS 60-80) and deep anesthesia group (group D)(BIS 40-60). Propofol was administrated by target controlled infusion system in pilot study. The target effect site concentration (ESC) of propofol was defined as the average of the ESC from BIS 80 to 60 or BIS 60 to 40 in group L or group D respectively. Mechanical stimuli were applied using von Frey filaments at the center of the left foot, and the pain threshold and VAS scores were evaluated. fMRI examinations were taken 1 week after pilot study with the following sequences: structure imaging+ functional imaging: functional imaging=stimulus sequence+propofol sequence, in which the stimulus sequence was 6 × (20 s on + 20 s off). This sequence was repeated after propofol sequence. RESULTS: As shown by fMRI, in group L, active brain regions of (the second stimulation-the first stimulation, P2-P1) were seen in cingulate gyrus, thalamus, and cerebellum, while active brain regions of (P1-P2) were seen in temporal lobe, frontal gyrus, and occipital lobe. In group D, the active brain region of (P2-P1) was only seen in cerebellum, while active brain regions of (P1-P2) were seen in cingulate gyrus and thalamus. Active brain regions of (deep-low) with propofol infusion in response to vFFs stimulation were observed in cerebellum. CONCLUSIONS: Propofol at different concentrations has different effect on the activation of brain regions. It may exert its analgesic effect via different mechanisms.


Assuntos
Encéfalo/fisiologia , Propofol/farmacologia , Estresse Mecânico , Adulto , Humanos , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
18.
Neurosci Bull ; 38(2): 166-180, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34435318

RESUMO

Neuroscientists have emphasized visceral influences on consciousness and attention, but the potential neurophysiological pathways remain under exploration. Here, we found two neurophysiological pathways of heart-brain interaction based on the relationship between oxygen-transport by red blood cells (RBCs) and consciousness/attention. To this end, we collected a dataset based on the routine physical examination, the breaking continuous flash suppression (b-CFS) paradigm, and an attention network test (ANT) in 140 immigrants under the hypoxic Tibetan environment. We combined electroencephalography and multilevel mediation analysis to investigate the relationship between RBC properties and consciousness/attention. The results showed that RBC function, via two independent neurophysiological pathways, not only triggered interoceptive re-representations in the insula and awareness connected to orienting attention but also induced an immune response corresponding to consciousness and executive control. Importantly, consciousness played a fundamental role in executive function which might be associated with the level of perceived stress. These results indicated the important role of oxygen-transport in heart-brain interactions, in which the related stress response affected consciousness and executive control. The findings provide new insights into the neurophysiological schema of heart-brain interactions.


Assuntos
Estado de Consciência , Percepção Visual , Conscientização , Encéfalo , Humanos , Oxigênio
19.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 33(5): 489-94, 2011 Oct.
Artigo em Zh | MEDLINE | ID: mdl-22338130

RESUMO

OBJECTIVE: To evaluate the clinical efficacy of domestic sevoflurane by comparing the pharmacokinetic and pharmacodynamic characteristics of domestic sevoflurane and an imported product. METHODS: Eighty patients undergoing general anesthesia for transabdominal hysterectomy were equally randomized into domestic sevoflurane group and imported sevoflurane group. The following data were recorded and compared: vital signs; change of sevoflurane concentrations in the induction period and recovery period; the time when inhaled sevoflurane concentration reached half of the pre-set concentration of the vaporizer; the time when the end-tidal sevoflurane concentration reached half of the pre-set concentration of the vaporizer; the time when the end-tidal sevoflurane concentration reached half of inhaled sevoflurane concentration; the time of the end-tidal sevoflurane concentration reached 0. 8 MAC in the induction period; the recovery time; the extubation time; and time to recovery of consciousness. RESULTS: The general conditions of the two groups were not significantly different. The pharmacokinetic and pharmacodynamic parameters at the intra-operative time points as well as the minimal alveolar concentration, the inspired and end-tidal sevoflurane concentrations, and the time to recovery of consciousness also showed no significant differences between the two groups. CONCLUSION: The domestic sevoflurane has similar pharmacokinetic and pharmacodynamic characteristics as the imported products. It can serve as a cost-effective product for transabdominal hysterectomy.


Assuntos
Anestésicos Inalatórios/farmacocinética , Histerectomia , Éteres Metílicos/farmacocinética , Adolescente , Adulto , Idoso , Anestesia por Inalação , Método Duplo-Cego , Feminino , Humanos , Pessoa de Meia-Idade , Sevoflurano , Adulto Jovem
20.
Environ Pollut ; 291: 118227, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34582919

RESUMO

Agricultural mulch film (AMF) is deemed an important source of microplastics (MPs) in agricultural soil (AS). However, quantitating the contribution of AMFs to MPs in farmland soil and surface water remains a considerable challenge to date. In the present study, a basic framework was developed to address these concerns. First, the concentrations of MPs in soil derived from AMF abrasion (CMP) and the total MPs from all sources in AS (CTMP) were measured. Then, the ratios of CMP to CTMP, i.e., the contribution of AMFs to MPs in AS, were calculated. The contribution of AMFs to MPs in surface water via soil erosion was calculated based on CTMP values, the ratios of CMP to CTMP, soil erosion intensities (SEIs), and farmland areas. Furthermore, the potential contribution of soil erosion to MPs in the ocean was estimated. In China, the inventory of MPs in surface AS in 2018 ranged from 4.9 × 106 to 1.0 × 107 tons according to our results. AMFs contributed 10%-30% of the CTMP with certainties of 60-95%. Assuming that all MPs in AS can be exhaustively transferred to surface water via soil erosion, the national mass transfer amount of MPs (MTTMP) from AS to surface water reached 1.2 × 105-2.2 × 105 tons (∼2% of the inventory of MPs in the AS of China); the fluxes of MPs into the ocean from AS were 3.4 × 104-6.6 × 104 tons, assuming that all MPs in the AS of coastal provinces enter the ocean. It is likely that AMFs contributed 10%-30% MTTMP and fluxes of MPs to the ocean according to the ratios of CMP to CTMP. Apparently, approximately 30% of the national MTTMP (i.e., the rate of MP flux to the ocean to MTTMP) was input to the ocean.


Assuntos
Microplásticos , Solo , China , Plásticos , Água
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