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1.
Opt Lett ; 48(6): 1355-1358, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36946926

RESUMO

A novel frequency-tunable microwave signal generation method is proposed by incorporating parity-time (PT) symmetry in period-one (P1) laser dynamics in an optically injected semiconductor laser. In this method, P1 oscillation enables a large frequency tuning range and PT symmetry leads to excellent side-mode suppression and low phase noise. In an experimental demonstration, the side-mode suppression ratio reaches 58.4 dB and the phase noise is -126.2 dBc/Hz at 10 kHz offset when generating a 6.98 GHz signal, which are improved by 44.5 dB and 13.5 dB, respectively, compared with the previously reported optoelectronic oscillator-based P1 oscillation. By simply adjusting the optical injection strength, the frequency of the microwave signal generated by PT symmetry P1 dynamics is tuned from 5.07 GHz to 15.22 GHz, in which the phase noise is kept below 120 dBc/Hz at 10 kHz offset. The proposed method is expected to find applications in high-performance wireless communication and radar systems.

2.
J Sleep Res ; 32(4): e13817, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-36690596

RESUMO

Insomnia displays heterogeneous trajectories across adolescence, which may induce addictive behaviours, including internet gaming disorder and substance use. This study aimed to investigate the latent trajectory classes of insomnia symptoms over 2 years and to examine the associations between insomnia trajectories and these addictive behaviours. Participants were 910 adolescents from six middle schools in Shanghai, China (52.7% males; mean age = 13.17 years). The three-wave survey measured insomnia symptoms, internet gaming disorder, substance use, depressive symptoms, and sociodemographic characteristics from 7th to 9th grade. Latent class growth modelling was performed to identify the latent trajectory classes of insomnia symptoms. Then multivariable logistic regressions were conducted within the best-fitting latent class growth model to examine the associations of insomnia trajectories with internet gaming disorder and substance use. Two latent trajectory classes of insomnia symptoms were recognised: the non-insomnia group (71.8%) and the insomnia group (28.2%). In the multivariable analysis controlling for baseline demographic variables and depressive symptoms, the insomnia group had a higher risk of developing internet gaming disorder (OR = 2.203 [95% CI: 1.258-3.858]) and substance use (OR = 2.215 [95% CI: 1.324-3.705]) compared with the non-insomnia group. These findings add to a growing body of research on heterogeneous trajectories of insomnia symptoms during adolescence, suggesting that intervention strategies are needed to target the characteristics or developmental patterns of different insomnia subgroups. The ultimate goal is to mitigate the impact of insomnia symptoms on adolescent addictive behaviours.


Assuntos
Comportamento Aditivo , Distúrbios do Início e da Manutenção do Sono , Masculino , Humanos , Adolescente , Feminino , Estudos Longitudinais , China/epidemiologia , Distúrbios do Início e da Manutenção do Sono/complicações , Distúrbios do Início e da Manutenção do Sono/epidemiologia , Inquéritos e Questionários , Comportamento Aditivo/complicações , Comportamento Aditivo/epidemiologia , Comportamento Aditivo/diagnóstico , Internet
3.
AIDS Care ; 35(7): 1001-1006, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-34963399

RESUMO

The Information-Motivation-Behavioral skills (IMB) model of antiretroviral therapy (ART) adherence was applied in people living with HIV/AIDS in Shanghai, China to understand how adherence-related information, motivation and behavioral skills would affect ART adherence. The LifeWindows Information-Motivation-Behavioral Skills ART Adherence Questionnaire (LW-IMB-AAQ) was translated into Chinese and used. The IMB model was then implemented by testing standardized path estimates with standard model fitness indices in the participants. 426 participants from 11 community centres in Putuo district of Shanghai were recruited, of which 95.3% reported a high level of adherence (>95% adherence). The fitness indices of the final adjusted model were χ2 = 6.110, df = 7, p = 0.527(>0.05), CFI = 1.000(>0.9) and RMSEA = 0.000 (<0.08). In the model, information, which was separated into two sections (the perceived effect of ART on health and knowledge about ART medication), had an indirect effect on the ART adherence through behavioral skills, while motivation did not have such an effect. Neither information nor motivation had a direct effect on ART adherence. In addition, motivation was related to the two sections of information. The feasibility of the IMB model of ART adherence is verified by its application to predictive of adherence-related behaviors among HIV+ patients in this study.


Assuntos
Infecções por HIV , Motivação , Humanos , Infecções por HIV/tratamento farmacológico , China/epidemiologia , Cooperação do Paciente , Antirretrovirais/uso terapêutico , Adesão à Medicação
4.
BMC Public Health ; 23(1): 1341, 2023 07 12.
Artigo em Inglês | MEDLINE | ID: mdl-37438732

RESUMO

OBJECTIVES: This study explores whether feelings of defeat (i.e., a sense of failed struggle and losing rank; referred to as defeat for simplicity) mediated the effect of work stress on depression/anxiety, the effect of interpersonal needs on depression/anxiety for Chinese industrial workers, and the possible moderating role of social support. METHOD: A cross-sectional study was conducted in Shenzhen, China in 2019, in total, 2023 industrial workers (of 2700 invited; response rate = 75%) completed a self-administered survey consisted of Job Stress Scale, Interpersonal Needs Questionnaire, Defeat Scale, Centre for Epidemiological Studies Depression Scale, Generalized Anxiety Disorder Scale, two face-valid questions for social support, as well as sociodemographic information. Moderated mediation model was tested and loop plots were applied to probe into the conditional effects of work and interpersonal stress on depression and anxiety symptoms. RESULT: Both the direct and indirect effect of work stress on depression and anxiety through defeat were significant (Work stress→ Depression: B = 0.035, p < .001, Work stress→ Defeat→ Depression: B = 0.034, p < .001; Work stress→ Anxiety: B = 0.038, p < .001, Work stress→ Defeat→ Anxiety: B = 0.045, p < .001). Meanwhile, defeat mediated the relationship of interpersonal needs with depression partially and the relationship of interpersonal needs with anxiety totally (Interpersonal needs→ Anxiety: B = 0.133, p < .001, Interpersonal needs→ Defeat→ Anxiety: B = 0.010, p = .537). Social support moderated the indirect path between interpersonal needs and depression/anxiety and buffered the effect. CONCLUSION: The mediating role of defeat and the moderator role of social support in the relationship between stress and depression/anxiety were confirmed in industrial workers. Workers who reported more work and interpersonal stress would report more defeat feelings, and then exhibited more depression and anxiety symptoms; this mediation effect was stronger for those who had lower social support, respectively.


Assuntos
Saúde Mental , Estresse Ocupacional , Humanos , Estudos Transversais , Ansiedade/epidemiologia , Transtornos de Ansiedade , Estresse Ocupacional/epidemiologia
5.
Sex Transm Infect ; 98(6): 438-444, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-34873028

RESUMO

OBJECTIVES: Suboptimal adherence to antiretroviral therapy (ART) dramatically hampers the achievement of the UNAIDS HIV treatment targets. This study aimed to develop a theory-informed predictive model for ART adherence based on data from Chinese. METHODS: A cross-sectional study was conducted in Shenzhen, China, in December 2020. Participants were recruited through snowball sampling, completing a survey that included sociodemographic characteristics, HIV clinical information, Information-Motivation-Behavioural Skills (IMB) constructs and adherence to ART. CD4 counts and HIV viral load were extracted from medical records. A model to predict ART adherence was developed from a multivariable logistic regression with significant predictors selected by Least Absolute Shrinkage and Selection Operator (LASSO) regression. To evaluate the performance of the model, we tested the discriminatory capacity using the concordance index (C-index) and calibration accuracy using the Hosmer and Lemeshow test. RESULTS: The average age of the 651 people living with HIV (PLHIV) in the training group was 34.1±8.4 years, with 20.1% reporting suboptimal adherence. The mean age of the 276 PLHIV in the validation group was 33.9±8.2 years, and the prevalence of poor adherence was 22.1%. The suboptimal adherence model incorporates five predictors: education level, alcohol use, side effects, objective abilities and self-efficacy. Constructed by those predictors, the model showed a C-index of 0.739 (95% CI 0.703 to 0.772) in internal validation, which was confirmed be 0.717 via bootstrapping validation and remained modest in temporal validation (C-index 0.676). The calibration capacity was acceptable both in the training and in the validation groups (p>0.05). CONCLUSIONS: Our model accurately estimates ART adherence behaviours. The prediction tool can help identify individuals at greater risk for poor adherence and guide tailored interventions to optimise adherence.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adulto , Fármacos Anti-HIV/uso terapêutico , Contagem de Linfócito CD4 , Estudos Transversais , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Humanos , Adesão à Medicação
6.
Opt Lett ; 47(22): 5921-5924, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37219137

RESUMO

In this Letter, dual-wavelength-injection period-one (P1) laser dynamics is proposed for the first time, to the best of our knowledge, to generate frequency-modulated microwave signals. By injecting light with two different wavelengths into a slave laser to excite P1 dynamics, the P1 oscillation frequency can be modulated without external control of the optical injection strength. The system is compact and stable. The frequency and bandwidth of the generated microwave signals can be easily adjusted by tuning the injection parameters. Through both simulations and experiments, the properties of the proposed dual-wavelength injection P1 oscillation are revealed, and the feasibility of the frequency-modulated microwave signal generation is verified. We believe that the proposed dual-wavelength injection P1 oscillation is an extension of laser dynamics theory, and the signal generation method is a promising solution for generating broadband frequency-modulated signals with good tunability.

7.
BMC Psychiatry ; 22(1): 17, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34991500

RESUMO

BACKGROUND: Migrant workers are a group susceptible for depression evolution due to occupational maladaptive triggers. The social rank theory illustrates the pathology process from defensive adaptation to depression, pointing out the early prevention of depression by discovering entrapment. This study aims to reveal the relationship between migrant workers' entrapment and depressive symptoms. METHODS: A total of 1805 migrant workers in Shenzhen were recruited by stratified multi-stage sampling. Sample's demographic, behavioral and psychosocial characteristics were described and analyzed to reveal the relationship between entrapment and depressive symptoms. The Receiver Operator Characteristic was performed to find the optimal cut-off point of Entrapment Scale for predicting depressive symptoms. RESULTS: In the binary logistic regression of sociodemographic variables, migrant workers who were married (univariate odds ratio (ORu) = 0.69, 95% Confidence Interval (CI) = 0.56-0.84), owned 1 or 2 children (ORu = 0.71, 95% CI = 0.58-0.86), had been working over 10 years (ORu = 0.71, 95% CI = 0.54-0.95), earned > 4999 yuan per month (ORu = 0.68, 95% CI = 0.47-0.99; multivariate odds ratio (ORm) = 0.57, 95% CI = 0.38-0.87) or with low risks of alcohol use disorders (ORu = 0.51, 95% CI = 0.34-0.75) had lower risks of depressive symptoms. After adjusted the aforementioned significant sociodemographic variables, migrant workers with severer entrapment were more likely to have depressive symptoms (adjusted odds ratio (ORa) = 1.13, 95% CI = 1.12-1.15). Besides, the study proved the reliability and validity of the Chinese version Entrapment Scale, preferring a two-dimensional structure, and 11 was the optimal cut-off value of this scale for predicting depressive symptoms among migrant workers. CONCLUSIONS: This result indicates the potential value of entrapment according to the social rank theory on facilitating early prevention of migrant works' depression and the application value of Entrapment Scale for effectively measuring mental status among migrant workers.


Assuntos
Alcoolismo , Migrantes , Criança , China , Estudos Transversais , Depressão/diagnóstico , Depressão/psicologia , Humanos , Reprodutibilidade dos Testes , Inquéritos e Questionários
8.
BMC Plant Biol ; 21(1): 80, 2021 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-33549055

RESUMO

BACKGROUND: As important forest tree species, biological stress and soil salinization are important factors that restrict the growth of Populus × euramericana. WRKYs are important transcription factors in plants that can regulate plant responses to biotic and abiotic stresses. In this study, PeWRKY31 was isolated from Populus × euramericana, and its bioinformation, salt resistance and insect resistance were analyzed. This study aims to provide guidance for producing salt-resistant and insect-resistant poplars. RESULTS: PeWRKY31 has a predicted open reading frame (ORF) of 1842 bp that encodes 613 amino acids. The predicted protein is the unstable, acidic, and hydrophilic protein with a molecular weight of 66.34 kDa, and it has numerous potential phosphorylation sites, chiefly on serines and threonines. PeWRKY31 is a zinc-finger C2H2 type-II WRKY TF that is closely related to WRKY TFs of Populus tomentosa, and localizes to the nucleus. A PeWRKY31 overexpression vector was constructed and transformed into Nicotiana tabacum L. Overexpression of PeWRKY31 improved the salt tolerance and insect resistance of the transgenic tobacco. Transcriptome sequencing and KEGG enrichment analysis showed the elevated expression of genes related to glutathione metabolism, plant hormone signal transduction, and MAPK signaling pathways, the functions of which were important in plant salt tolerance and insect resistance in the overexpressing tobacco line. CONCLUSIONS: PeWRKY31 was isolated from Populus × euramericana. Overexpression of PeWRKY31 improved the resistance of transgenic plant to salt stress and pest stress. The study provides references for the generation of stress-resistant lines with potentially great economic benefit.


Assuntos
Nicotiana/genética , Nicotiana/fisiologia , Proteínas de Plantas/genética , Populus/genética , Tolerância ao Sal/genética , Sequência de Aminoácidos , Animais , Clonagem Molecular , Regulação da Expressão Gênica de Plantas , Insetos/fisiologia , Filogenia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Plantas Geneticamente Modificadas , Frações Subcelulares/metabolismo , Transcriptoma/genética
9.
AIDS Behav ; 25(5): 1597-1605, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33215274

RESUMO

Transgender women (TGW) worldwide report disproportionate violence victimization, depression and condomless anal intercourse (CAI), but the mechanism of the coexistence remains unclear. Using snowball sampling, we recruited 198 self-identified TGW in Shenyang, China between April 2017 and July 2017, and conducted confidential questionnaire survey among them. Positive HIV status was reported by 49 (24.7%) participants. 117 (59.1%) reported at least one type of lifetime violence victimization, with transactional sexual partners being the main violence perpetrators. 108 (54.5%) reported mild to severe depression. 105 (53.0%) reported having CAI with their sexual partners during the last 6 months. Path analysis showed that the association between participants' violence victimization and CAI was fully mediated by their depression (indirect effect: 0.083, p = 0.014; direct effect: 0.137, p = 0.121). We suggest to incorporate violence screening and prevention and mental health services into intervention strategies to prevent CAI among Chinese TGW.


Assuntos
Vítimas de Crime , Infecções por HIV , Pessoas Transgênero , China/epidemiologia , Depressão/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle , Homossexualidade Masculina , Humanos , Masculino , Prevalência , Comportamento Sexual , Parceiros Sexuais , Violência
10.
BMC Psychiatry ; 21(1): 328, 2021 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215241

RESUMO

BACKGROUND: Perception of entrapment can emerge when someone feels trapped in an aversive situation and incapable of escape. Depression is closely related to the construct of entrapment. In China, men who have sex with men (MSM) have a high prevalence of depression; therefore, a tool to evaluate entrapment in this population is needed. We evaluated the validity and reliability of the Chinese version of the entrapment scale (ES) and the relationship to depression among MSM in Shanghai, China. METHODS: We recruited 304 MSM from four districts in Shanghai, China. Participants completed health behavior questionnaires that included baseline information and psychological measurements such as the ES and Patient Health Questionnaire (PHQ-9). The sample was randomly divided into two groups for exploratory factor analysis (n = 143) and confirmatory factor analysis (n = 161). Criterion validity was tested to explore the correlation between the ES and PHQ-9 scores. The reliability of the ES was evaluated with internal consistency reliability (Cronbach's α coefficient) and split-half reliability (Spearman-Brown coefficient). We performed hierarchical regression analysis to determine the variance explained of entrapment to predicting depressive symptoms after adjusting for sociodemographic factors. Finally, receiver operator characteristic curve analysis was performed to measure the optimal ES cut-off value for predicting depression. RESULTS: Factor analysis showed the ES had one principal component, and one-dimensional scale had more acceptable model fit indices than two-dimensional model. The correlation coefficient between the ES and PHQ-9 scores was 0.756 (P < 0.01). The Cronbach's α coefficient was 0.970 and the Spearman-Brown coefficient was 0.976. ES scores significantly predicted an additional 45.1% of depressive symptoms after controlling for sociodemographic characteristics in the MSM population (ß = 0.689, P < 0.001). The optimum cut-off value was 23, which had a sensitivity of 70% and a specificity of 85.4%. CONCLUSIONS: The Chinese version of the ES has good validity and reliability in the MSM population in Shanghai, and can be used to evaluate perception of entrapment among MSM. The findings confirmed an association between entrapment and depression.


Assuntos
Homossexualidade Masculina , Minorias Sexuais e de Gênero , China/epidemiologia , Depressão/diagnóstico , Depressão/epidemiologia , Humanos , Masculino , Psicometria , Reprodutibilidade dos Testes , Inquéritos e Questionários
11.
J Adolesc ; 92: 1-9, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34246122

RESUMO

INTRODUCTION: Internet gaming disorder (IGD) was popular among adolescents worldwide, but whether some associated factors could contribute to the development of IGD was unclear. This longitudinal study explored the temporal stability of IGD over one year and determined the predictors for IGD incidence. METHODS: Participants were 1121 adolescents from six junior high schools in Shanghai, China (50.6% males; median age = 13.0 years). The baseline and follow-up questionnaire survey measured IGD, time spent on gaming, depressive symptoms, insomnia condition, substance use and background variables from 7th to 8th grade. Multivariate logistic regression analysis was conducted to test the associations between other factors and IGD incidence. RESULTS: IGD incidence was 7.7% at one-year follow-up. Gender, family financial condition, parental educational level, time spent on gaming, insomnia condition and depressive symptoms were associated with IGD incidence in univariate analysis, whereas only gender, family financial condition, time spent on gaming and depressive symptoms were associated with IGD incidence in multivariate logistic regression. CONCLUSIONS: IGD might persist for years during adolescence. After controlling for sociodemographic factors, time spent on gaming and depressive symptoms were independent predictors for IGD incidence.


Assuntos
Comportamento Aditivo , Jogos de Vídeo , Adolescente , Comportamento Aditivo/epidemiologia , China/epidemiologia , Depressão/epidemiologia , Feminino , Humanos , Incidência , Internet , Transtorno de Adição à Internet , Estudos Longitudinais , Masculino
12.
BMC Psychiatry ; 20(1): 460, 2020 09 23.
Artigo em Inglês | MEDLINE | ID: mdl-32967648

RESUMO

BACKGROUND: High prevalence and strong relationships among suicidal ideation, Internet gaming disorder (IGD), insomnia, and depression have been reported for adolescents worldwide, but the mechanism underlying these psychological problems remains unclear. This cross-sectional study explored the mediating effect of insomnia and depression on the association between IGD and suicidal ideation. METHODS: Participants were 1066 adolescents (median age = 13.0 years) with Internet games exposure in the previous 12 months from junior high schools in Shanghai, China. Questionnaire measures of suicidal ideation, IGD, insomnia, depressive symptoms, and background characteristics were obtained. Path analysis was conducted to test the multiple mediating roles of insomnia and depression. RESULTS: Suicidal ideation, IGD, insomnia, and depression prevalence was 27.2, 13.6, 9.2, and 17.0%, respectively. A serial multiple mediation model was generated. The mediation effect of insomnia and depression on the pathway from IGD to suicidal ideation was 45.5% (direct effect: standardized estimate [Std. estimate] = 0.186; total indirect effect: Std. estimate = 0.155). The association between IGD and depression was partially mediated by insomnia (direct effect: Std. estimate = 0.211; indirect effect: Std. estimate = 0.135). The proposed model fit the data well. CONCLUSIONS: Insomnia and depression may serially mediate the association between IGD and suicidal ideation. IGD was positively associated with insomnia, then with depression, which in turn positively contributed to suicidal ideation. We suggest greater monitoring of Internet use and prevention of insomnia and depression to mitigate the risk of suicidal ideation among Chinese adolescents.


Assuntos
Distúrbios do Início e da Manutenção do Sono , Ideação Suicida , Adolescente , China/epidemiologia , Estudos Transversais , Depressão/epidemiologia , Humanos , Lactente , Internet , Transtorno de Adição à Internet , Distúrbios do Início e da Manutenção do Sono/epidemiologia
13.
Phytopathology ; 106(7): 693-701, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26882850

RESUMO

Citrus canker, caused by Xanthomonas citri ssp. citri, is a serious disease that causes substantial economic losses to the citrus industry worldwide. The bactericide bismerthiazol has been used to control rice bacterial blight (X. oryzae pv. oryzae). In this paper, we demonstrate that bismerthiazol can effectively control citrus canker by both inhibiting the growth of X. citri ssp. citri and triggering the plant's host defense response through the expression of several pathogenesis-related genes (PR1, PR2, CHI, and RpRd1) and the nonexpresser of PR genes (NPR1, NPR2, and NPR3) in 'Duncan' grapefruit, especially at early treatment times. In addition, we found that bismerthiazol induced the expression of the marker genes CitCHS and CitCHI in the flavonoid pathway and the PAL1 (phenylalanine ammonia lyase 1) gene in the salicylic acid (SA) biosynthesis pathway at different time points. Moreover, bismerthiazol also induced the expression of the priming defense-associated gene AZI1. Taken together, these results indicate that the induction of the defense response in 'Duncan' grapefruit by bismerthiazol may involve the SA signaling pathway and the priming defense and that bismerthiazol may serve as an alternative to copper bactericides for the control of citrus canker.


Assuntos
Citrus paradisi/efeitos dos fármacos , Imunidade Vegetal/efeitos dos fármacos , Compostos de Sulfidrila/farmacologia , Tiadiazóis/farmacologia , Xanthomonas/efeitos dos fármacos , Citrus paradisi/genética , Citrus paradisi/metabolismo , Ciclopentanos/metabolismo , Expressão Gênica/efeitos dos fármacos , Ácidos Indolacéticos/metabolismo , Oxilipinas/metabolismo , Doenças das Plantas , Ácido Salicílico/metabolismo , Transdução de Sinais/efeitos dos fármacos
14.
J Agric Food Chem ; 72(20): 11405-11414, 2024 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-38717990

RESUMO

This study investigated the multiple herbicide resistance (MHR) mechanism of one Echinochloa crus-galli population that was resistant to florpyrauxifen-benzyl (FPB), cyhalofop-butyl (CHB), and penoxsulam (PEX). This population carried an Ala-122-Asn mutation in the acetolactate synthase (ALS) gene but no mutation in acetyl-CoA carboxylase (ACCase) and transport inhibitor response1 (TIR1) genes. The metabolism rate of PEX was 2-fold higher, and the production of florpyrauxifen-acid and cyhalofop-acid was lower in the resistant population. Malathion and 4-chloro-7-nitrobenzoxadiazole (NBD-Cl) could reverse the resistance, suggesting that cytochrome P450 (CYP450) and glutathione S-transferase (GST) contribute to the enhanced metabolism. According to RNA-seq and qRT-PCR validation, two CYP450 genes (CYP71C42 and CYP71D55), one GST gene (GSTT2), two glycosyltransferase genes (rhamnosyltransferase 1 and IAAGLU), and two ABC transporter genes (ABCG1 and ABCG25) were induced by CHB, FPB, and PEX in the resistant population. This study revealed that the target mutant and enhanced metabolism were involved in the MHR mechanism in E. crus-galli.


Assuntos
Sistema Enzimático do Citocromo P-450 , Echinochloa , Resistência a Herbicidas , Herbicidas , Mutação , Proteínas de Plantas , Resistência a Herbicidas/genética , Herbicidas/farmacologia , Herbicidas/metabolismo , Echinochloa/genética , Echinochloa/efeitos dos fármacos , Echinochloa/metabolismo , Echinochloa/crescimento & desenvolvimento , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Sistema Enzimático do Citocromo P-450/genética , Sistema Enzimático do Citocromo P-450/metabolismo , Acetil-CoA Carboxilase/genética , Acetil-CoA Carboxilase/metabolismo , Plantas Daninhas/efeitos dos fármacos , Plantas Daninhas/genética , Plantas Daninhas/metabolismo , Acetolactato Sintase/genética , Acetolactato Sintase/metabolismo , Butanos , Nitrilas , Sulfonamidas , Uridina/análogos & derivados
15.
Adv Sci (Weinh) ; 11(10): e2305563, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38145959

RESUMO

Diabetic nephropathy (DN) is a serious microvascular complication of diabetes. Ferroptosis, a new form of cell death, plays a crucial role in the pathogenesis of DN. Renal tubular injury triggered by ferroptosis might be essential in this process. Numerous studies demonstrate that the vitamin D receptor (VDR) exerts beneficial effects by suppressing ferroptosis. However, the underlying mechanism has not been fully elucidated. Thus, they verified the nephroprotective effect of VDR activation and explored the mechanism by which VDR activation suppressed ferroptosis in db/db mice and high glucose-cultured proximal tubular epithelial cells (PTECs). Paricalcitol (PAR) is a VDR agonist that can mitigate kidney injury and prevent renal dysfunction. PAR treatment could inhibit ferroptosis of PTECs through decreasing iron content, increasing glutathione (GSH) levels, reducing malondialdehyde (MDA) generation, decreasing the expression of positive ferroptosis mediator transferrin receptor 1 (TFR-1), and enhancing the expression of negative ferroptosis mediators including ferritin heavy chain (FTH-1), glutathione peroxidase 4 (GPX4), and cystine/glutamate antiporter solute carrier family 7 member 11 (SLC7A11). Mechanistically, VDR activation upregulated the NFE2-related factor 2/heme oxygenase-1 (Nrf2/HO-1) signaling pathway to suppress ferroptosis in PTECs. These findings suggested that VDR activation inhibited ferroptosis of PTECs in DN via modulating the Nrf2/HO-1 signaling pathway.


Assuntos
Diabetes Mellitus , Nefropatias Diabéticas , Ferroptose , Animais , Camundongos , Células Epiteliais , Glutationa , Heme Oxigenase-1 , Fator 2 Relacionado a NF-E2 , Receptores de Calcitriol , Transdução de Sinais
16.
Eur J Pharm Biopharm ; : 114389, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945407

RESUMO

Liposomes represent one of the most extensively studied nano-carriers due to their potential in targeted drug delivery. However, the complex in vivo fate, particularly under pathological conditions, presents challenges for clinical translation of liposomal therapeutics. Liver serves as the most important organ for liposome accumulation and metabolism. Unfortunately, the fate of liposomes under pathological liver conditions has been significantly overlooked. This study aimed to investigate the in vivo pharmacokinetic profile and biodistribution profile of liposomes under drug-induced liver injury (DILI) conditions. Two classic DILI animal models, i.e. acetaminophen-induced acute liver injury (AILI) and triptolide-induced subacute liver injury (TILI), were established to observe the effect of pathological liver conditions on the in vivo performance of liposomes. The study revealed significant changes in the in vivo fate of liposomes following DILI, including prolonged blood circulation and enhanced hepatic accumulation of liposomes. Changes in the composition of plasma proteins and mononuclear phagocyte system (MPS)-related cell subpopulations collectively led to the altered in vivo fate of liposomes under liver injury conditions. Despite liver injury, macrophages remained the primary cells responsible for liposomes uptake in liver, with the recruited monocyte-derived macrophages exhibiting enhanced ability to phagocytose liposomes under pathological conditions. These findings indicated that high capture of liposomes by the recruited hepatic macrophages not only offered potential solutions for targeted delivery, but also warned the clinical application of patients under pathological liver conditions.

17.
Pharm Dev Technol ; 18(4): 804-12, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-22335624

RESUMO

The purpose of this study is to develop a new formulation for prostaglandin E1 (PGE1)-loaded lipid emulsion (Lipo-PGE1) with improved stability and reduced biodegradation. High-pressure homogenization was used to prepare the Lipo-PGE1, and high-performance liquid chromatography and accelerated test were used to evaluate its physicochemical stability. A tissue homogenate incubation test was firstly established and validated to assess its biodegradation. The factors influencing the stability of Lipo-PGE1, including oil phase, emulsifier, pH value, and drug concentration were systematically investigated. The optimized formulation consisting of poloxamer188 1.5% (w/v), egg lecithin 0.5% (w/v), soybean oil 10.0% (w/v), oleic acid 0.24% (w/v), and glycerol 2.2% (w/v), with the pH value at 4.0, was defined and characterized. When compared with the currently available commercial product of Lipo-PGE1, the degradation percentage of this optimized Lipo-PGE1 reduced by 47.1% after sterilization, the drug remaining percentage increased by 13.9% after storage at 4°C over 6 months. Also, a significant reduction in biodegradation of the optimized Lipo-PGE1 in comparison with the commercial Lipo-PGE1 was observed by a tissue homogenate incubation test. Overall, we provided a novel formulation for Lipo-PGE1 with a better physicochemical stability and a less biodegradation than the currently available commercial product of Lipo-PGE1, indicating its potential superiority in clinical application.


Assuntos
Alprostadil/administração & dosagem , Excipientes/química , Lipídeos/química , Inibidores da Agregação Plaquetária/administração & dosagem , Alprostadil/química , Alprostadil/metabolismo , Animais , Cromatografia Líquida de Alta Pressão/métodos , Composição de Medicamentos , Estabilidade de Medicamentos , Armazenamento de Medicamentos , Emulsões , Concentração de Íons de Hidrogênio , Técnicas In Vitro , Camundongos , Inibidores da Agregação Plaquetária/química , Inibidores da Agregação Plaquetária/metabolismo , Fatores de Tempo
18.
PeerJ ; 11: e15668, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37483969

RESUMO

The selection and utilization of ornamental plants that are highly tolerant to salt are helpful for landscape construction and the ecological protection of coastal and arid areas. To evaluate salt tolerance, one of the most used methods is the observation of seed germination under salt stress. Therefore, this work aimed to evaluate the influence of different concentrations of NaCl in water absorption, germination, and respiratory metabolism in seeds of different Flueggea suffruticosa genotypes. P2 and P27, salt-sensitive and salt-tolerant line s of F. suffruticosa, were chosen for treatment with 0, 40, 80, 120, 160, 200, and 240 mM NaCl. F. suffruticosa under salt stress exhibited inhibition of seed germination. The seeds of F. suffruticosa have different times for the physiological phases of water absorption with different NaCl concentrations. Salt stress retarded the seed water absorption process, and it depended on seed genotypes for F. suffruticosa. Soluble sugars accumulated in both P2 and P27 under salt stress. Meanwhile, the activities of hexokinase, 6-phosphofructokinase, pyruvate kinase, pyruvate dehydrogenase, citrate synthase, and glucose-6-phosphate dehydrogenase were overall increased in P27 after salt treatment, which caused increases in pyruvic acid and citric acid. The citrate synthase and glucose-6-phosphate dehydrogenase activities decreased in P2. These results suggest that the respiratory metabolism of salt-tolerant F. suffruticosa was enhanced, compared with the salt-sensitive line, to ameliorate the repression of seed germination under salt stress. The different changes in respiratory metabolism could influence the degree of salt tolerance.


Assuntos
Germinação , Sementes , Glucosefosfato Desidrogenase/metabolismo , Citrato (si)-Sintase/metabolismo , Cloreto de Sódio/metabolismo , Estresse Salino , Água/metabolismo
19.
Artigo em Inglês | MEDLINE | ID: mdl-37714051

RESUMO

Iridoid glycosides (geniposide (GP), genipin-1-gentiobioside (GB), etc.) and crocins (crocin Ⅰ (CR1), crocin Ⅱ(CR2), etc.) are two main bioactive components in Gardeniae Fructus (GF), which is a famous traditional Chinese medicine. Iridoid glycosides exhibit many activities and are used to manufacture gardenia blue pigment for the food industry. Crocins are rare natural water-soluble carotenoids that are often used as food colorants. A sequential macroporous resin column chromatography technology composed of HC-500B and HC-900B resins was developed to selectively separate iridoid glucosides and crocins from GF. The adsorption of GP on HC-900B resin was an exothermic process. The adsorption of CR1 on HC-500B resin was an endothermic process. The two kinds of components were completely separated by a sequential resin column. GB and GP were mainly found in product 1 (P1) with purities of 11.38% and 46.83%, respectively, while CR1 and CR2 were mainly found in product 2 (P2) with purities of 12.32% and 1.40%, respectively. The recovery yields of all the compounds were more than 80%. The above results showed that sequential resin column chromatography technology achieved high selectivity and recovery yields. GF extract, P1 and P2 could significantly inhibit the secretion of nitric oxide (NO), tumor necrosis factor α (TNF-α) and interleukin-6 (IL-6) in lipopolysaccharide (LPS)-induced RAW264.7 cells, indicating that iridoid glycosides and crocins provide a greater contribution to the anti-inflammatory activity of GF. At the same time, compared to the GF extract and P1, P2 exhibited stronger scavenging activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radicals, indicating that crocins may provide a significant contribution to the antioxidant activity of GF.


Assuntos
Medicamentos de Ervas Chinesas , Gardenia , Glucosídeos Iridoides/análise , Antioxidantes/farmacologia , Gardenia/química , Cromatografia Líquida de Alta Pressão/métodos , Carotenoides/farmacologia , Glicosídeos Iridoides/análise , Medicamentos de Ervas Chinesas/análise , Anti-Inflamatórios/farmacologia
20.
Plants (Basel) ; 12(23)2023 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-38068696

RESUMO

Penoxsulam is an acetolactate synthase (ALS)-inhibiting herbicide usually applied by post-emergence foliar spraying (PFS) for the control of Echinochloa crus-galli and numerous annual weeds in paddy fields. Herbicides applied by foliar spraying can have negative impacts on the environment, ecosystems, and human health. In this study, the response of E. crus-galli and rice to the PFS and post-emergence water-dispersal (PWD) applications of penoxsulam, and the differences in the detoxification displayed by them between the two treatment methods were compared. The results showed that the PWD application of penoxsulam provides a similar control efficacy against E. crus-galli as PFS at the 1-, 3-, and 5-leaf stages. Meanwhile, the PWD application had a higher safety for the rice. After being treated with 30 g a.i. ha-1 penoxsulam, residues were not detected in the rice treated by the PWD application method, whereas, with the PFS treatment, there was 59.0 µg/kg penoxsulam remaining. With the PFS application, there were many more residues of penoxsulam in the E. crus-galli than with the PWD method; the amount of residues was 32-fold higher 12 h after treatment. The in vitro enzyme activity assays revealed that the activities of ALS, glutathione-S-transferase (GST), and cytochrome P450 monooxygenases (P450) were increased in the PWD treatments, and were 1.5-, 1.3-, and 2.3-fold higher than with PFS 72 h after treatment. The real-time quantitative PCR (qRT-PCR) revealed that the GST1 and P450 genes, CYP81A14, CYP81A12, CYP81A18, and CYP81A21 were upregulated with the PWD application versus PFS in the E. crus-galli. In summary, these results demonstrate that the herbicidal activity was not affected by the upregulation of target and metabolic enzyme activities with the PWD application of penoxsulam. This research could contribute to application strategies reducing the risk of rice injury and environmental impacts by using water-dispersal formulations of penoxsulam.

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