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1.
Int J Biol Macromol ; 260(Pt 2): 129539, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38244737

RESUMO

5-Hydroxytryptamine (5-HT) and its derivative bufotenine, which possess important physiological functions, are the primary active components in the secretions of toad parotid and skin gland. However, the biosynthetic pathway of these substances remains unclear in toads. To characterize toad's Aromatic-L-amino-acid decarboxylase (AADC), the key enzyme in the predicted 5-HT derivatives biosynthetic pathway, the full-length cDNA of AADC from Bufo bufo gargarizans (BbgAADC) was cloned from the parotoid gland of B. bufo gargarizans. The recombinant BbgAADC exhibited optimal expression in E. coli BL21 (DE3) containing pCold-BbgAADC after induction for 16 h at 15 °C with 0.3 mM IPTG, resulting in substantial yields of soluble proteins. The enzymological properties of BbgAADC were assessed, and it was determined that the optimal reaction temperature was 37 °C, the optimal pH was 8.6, and the optimum molar ratio of pyridoxal-5'-phosphate (PLP) to BbgAADC was found to be 3.6:1. Additionally, high substrate specificity was observed, as BbgAADC could catalyze the production of 5-HT from 5-hydroxytryptophan (5-HTP) but not dopamine or tryptamine from levodopa or tryptophan, respectively. The Km of the recombinant protein BbgAADC was 0.2918 mM and the maximum reaction rate (Vmax) was 1.182 µM·min-1 when 5-HTP was used as substrate. The Kcat was 0.0545 min-1, and Kcat/Km was 0.1868 mM-1·min-1. To elucidate the mechanism of BbgAADC, molecular docking was performed with PLP and 5-HTP, or the external aldimine formed by 5-HTP and PLP. The results indicated that the active sites for BbgAADC to bind with PLP were K303, H192, N300, A148, F309, T246, A273, and T147. W71, Y79, F80, P81, T82, H192, T246, N300, H302, F309, and R477 served as catalytically active sites for the binding of BbgAADC to 5-HTP. Furthermore, R447, W71, S149, N300, A148, and T147 of BbgAADC were involved in the decarboxylation reaction of the aldimine formed by PLP and 5-HTP.


Assuntos
5-Hidroxitriptofano , Bufo bufo , Animais , Bufo bufo/metabolismo , 5-Hidroxitriptofano/genética , 5-Hidroxitriptofano/metabolismo , Serotonina/farmacologia , Escherichia coli/genética , Escherichia coli/metabolismo , Simulação de Acoplamento Molecular , Descarboxilases de Aminoácido-L-Aromático/genética , Descarboxilases de Aminoácido-L-Aromático/metabolismo , Bufonidae/metabolismo , Clonagem Molecular
2.
Evol Psychol ; 21(2): 14747049231179151, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37272073

RESUMO

Some men who have sex with men (MSM) having more casual sex and sexual partners is interpreted to be a sign of mental disorder and used to justify negative attitudes toward them by some. MSM may internalize this attitude causing internalized homophobia (IH). According to the sexual strategies theory, MSM having more casual sex is the result of differences between men's and women's sexual strategies and is unrelated to sexual orientation. We investigated whether this explanation would reduce IH and improve mental health in MSM. We recruited 255 Chinese MSM online using Wenjuanxing, Douban, Weibo, Tieba, and Blued and divided them using simple randomization into an experimental group (n = 77; sexual strategies explanation provided), an active control group (n = 99; minority stress explanation provided), and a control group (n = 79; no intervention) with pretest (N = 255); a 1 week post-test (n = 195); and a 1 month follow-up test (n = 170) of outcome measures. IH, mental distress (MD), sort-term mating orientation, and risky sexual behaviors were measured online. The data were analyzed by SPSS 28. IH was associated with MD while being married was associated with IH and sexual contact with women with both more IH and MD as were not being masculine and self-identifying as straight. The sexual strategies explanation reduced IH related to pathologizing sexual behaviors and high-risk sexual behaviors while the minority stress explanation reduced MD. Providing a sexual strategies explanation may be used to de-stigmatize casual sex among MSM.


Assuntos
Homossexualidade Masculina , Minorias Sexuais e de Gênero , Humanos , Masculino , Feminino , Homossexualidade Masculina/psicologia , Homofobia/psicologia , Comportamento Sexual/psicologia , Homens , China
3.
Front Psychol ; 14: 1143584, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37151342

RESUMO

Introduction: Homophobic discrimination and stigmatization, especially from healthcare professionals, are important stressors for gay men. Homophobia may be partly rooted in seeing some gay men having casual sex and many sexual partners as a signal of mental problems. Sexual Strategies Theory (SST) suggests that such sexual behavior is a result of different sexual strategies men and women tend to adopt and is unrelated to sexual orientation per se. This study aimed to investigate (1) the effectiveness of providing an SST explanation for gay men's sexual behavior in reducing homophobia among both lay persons and healthcare professionals; (2) differences in homophobia between healthcare professionals and lay people and also between medical and non-medical professionals. Methods: The main analyses included 492 heterosexual participants recruited online via Chinese social media and sample services in 2021. Of these, 227 were healthcare professionals (128 medical, 99 non-medical) and 265 were lay people. The participants were randomly assigned into an experimental group given the SST explanation (n = 126), an active control group given a Minority Stress (MS) explanation (n = 184), and a control group (n = 182). After the manipulation, homophobia, knowledge about homosexuality, professional homophobic attitude, gay affirmative practice, and contact with gay men were assessed. Results: The results of factor analysis suggested dividing homophobia into Oppressing Homophobia (Oppressing HP) describing believing that gay men should have fewer rights and Pathologizing Homophobia (Pathologizing HP) describing believing that the sexual behavior of gay men is a signal of mental problem. Importantly, the SST explanation reduced Pathologizing HP while the MS explanation reduced Oppressing HP. Healthcare professionals reported more Oppressing HP than lay people, and medical professionals conducted less gay affirmative practice than non-medical professionals. Conclusion: An SST explanation can potentially reduce some aspects of homophobia among both healthcare professionals and lay people. Also, worryingly, Chinese healthcare professionals, especially medical professionals, reported more homophobia than lay individuals.

5.
Joint Bone Spine ; 88(6): 105078, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-32950704

RESUMO

OBJECTIVE: The prevalence of gout is increasing but studies of its clinical features in large samples are lacking. This study aimed to clarify changes in the clinical manifestations of gout in China over the last decade and investigate the clinical features and risk factors of early-onset gout. METHODS: Clinical manifestations were compared between 9754 gout patients who first presented at our clinic with gout in 2008-2012 (earlier group) or 2013-2018 (later group). Gout onset≤30 years old was defined as early-onset and>30 years as late-onset. Clinical features and risk factors were compared between the groups. RESULTS: The gout-onset age was 4.14 years younger and the percentage of early-onset gout (3827 patients) was higher in the later 2013-2018 group (5979 patients). The disease duration was significantly shorter (5.72±0.09 vs. 6.01±0.11 years P < 0,05) and the ratio of patients with tophi was correspondingly lower in the later group (22.0% vs. 20.0%, P < 0,05). More patients were obese (32.6% vs. 37.7%, P<0.001) and serum urate levels (465.0±1.9µmol/L vs. 485.5±1.5µmol/L) were significantly higher in the later group. As the age of gout-onset became younger, we did the multivariate logistic regression and identified a positive family history, male sex, obesity, elevated serum urate, and sugar-sweetened soft drinks as independent predictors of early-onset gout. CONCLUSION: The manifestations of gout in China have changed over the last decade, associated with a trend towards younger onset.


Assuntos
Gota , Adulto , Pré-Escolar , China/epidemiologia , Gota/complicações , Gota/diagnóstico , Gota/epidemiologia , Humanos , Masculino , Obesidade , Prevalência , Fatores de Risco
6.
Psychophysiology ; 54(7): 1040-1053, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28334440

RESUMO

Previous research has shown that consummatory ERP components are sensitive to contextual valence. The present study investigated the contextual valence effect across anticipatory and consummatory phases by requiring participants to play a simple gambling task during a gain context and a loss context. During the anticipatory phase, the cue-P3 was more positive in the gain context compared to the loss context, whereas the stimulus-preceding negativity (SPN) was comparable across the two contexts. With respect to the consummatory phase, the feedback-related negativity (FRN) in response to the zero-value outcome was more negative in the gain versus loss context, whereas the feedback P3 (fb-P3) in response to the zero-value outcome was insensitive to contextual valence. These findings suggest that contextual valence effect occurs at a relative early stage of both the reward anticipation and consumption. Moreover, across the gain and loss contexts, the SPN was selectively correlated with the FRN, whereas the cue-P3 was selectively associated with the fb-P3, pointing to a close association between the anticipatory and consummatory phases in reward dynamics.


Assuntos
Córtex Cerebral/fisiologia , Potenciais Evocados P300 , Recompensa , Adolescente , Adulto , Antecipação Psicológica/fisiologia , Sinais (Psicologia) , Eletroencefalografia , Feminino , Jogo de Azar , Jogos Experimentais , Humanos , Masculino , Adulto Jovem
7.
Int J Phytoremediation ; 18(4): 358-63, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26515779

RESUMO

Cd hyperaccumulator Solanum nigrum L. was a promising plant used to simultaneously remediate Cd-PAHs combined pollution soil through its extra accumulation capacity and rhizosphere degradation. This article compared the strengthening remediation role of cysteine (Cys), glycine (Gly) and glutamic acid (Glu) with EDTA and TW80. The results showed that the addition of 0.03 mmol L(-1) Cys, Gly, and Glu didn't significantly impact (p < 0.05) shoot biomass of S. nigrum, but obviously increased Cd concentration. Therefore, Cd capacity (µg pot(-1)) in shoots of S. nigrum was significantly increased (p < 0.05) by 37.7% compared to the control without reagent added. At the meantime, the PAHs degradation ratio in rhizoshpere was increased by 34.5%. Basically, the improving role of Cys, Gly, and Glu was higher than EDTA and TW80. The main reasons of enhanced the accumulation of S. nigrum to Cd might lie in the addition of Cys, Gly, and Glu which reduced pH and increased extractable Cd concentration in rhizosphere and phytochelatines (PCs) concentration in leaves. As for the degradation of PAHs in rhizosphere, increased microorganism number might be play important role.


Assuntos
Aminoácidos/metabolismo , Cádmio/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/metabolismo , Poluentes do Solo/metabolismo , Solanum nigrum/metabolismo , Aminoácidos/análise , Biodegradação Ambiental , Cádmio/análise , Meios de Cultura/química , Meios de Cultura/metabolismo , Folhas de Planta/química , Folhas de Planta/metabolismo , Hidrocarbonetos Policíclicos Aromáticos/análise , Poluentes do Solo/análise , Solanum nigrum/química
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