RESUMO
Aptamers are widely used in various biomedical areas as novel molecular recognition elements, however, short single-stranded DNA (ssDNA) or RNA oligonucleotides are easily degraded by nucleases in biological fluids. This problem can be solved by circularizing aptamers with circular ligases. Herein, a moderately thermostable ssDNA ligase was expressed and purified. The purified ligase showed good circularization activity for different length substrates and much higher circularization efficiency than T4 RNA ligase 1. Biochemical characterization revealed that the enzyme showed optimal circularization activity at pH 7.5 and 50 áµC. Mn2+ and Mg2+ increased enzyme circularization activity, with Mn2+ having higher activity than Mg2+. The optimal concentrations of Mn2+ and ligase were 1.25-2.5 mM and 0.02 nM, respectively. The kinetic parameters Km, Vmax and Kcat of ssDNA ligase were 1.16 µM, 10.71 µM/min, and 10.7 min-1, respectively. The ssDNA ligase efficiency was nucleotide-dependent, and 5'-G and 3'-T were the most ligase-favored terminal nucleotides. In addition, the affinity and stability of the circular aptamer were determined. The affinity constant (KD) was 4.9 µM, and the stability increased compared to its linear form. Molecular docking results showed that the circular aptamer bound to the target via two hydrogen bonds. This study provides a simple and efficient aptamer circularization modification method for improving aptamer stability and expanding its applications.
Assuntos
Aptâmeros de Nucleotídeos , DNA de Cadeia Simples , Ligases/metabolismo , Simulação de Acoplamento Molecular , RNA/química , Aptâmeros de Nucleotídeos/químicaRESUMO
The presence and impact of toxins have been detected in various regions worldwide ever since the discovery of azaspiracids (AZAs) in 1995. These toxins have had detrimental effects on marine resource utilization, marine environmental protection, and fishery production. Over the course of more than two decades of research and development, scientists from all over the world have conducted comprehensive studies on the in vivo metabolism, in vitro synthesis methods, pathogenic mechanisms, and toxicology of these toxins. This paper aims to provide a systematic introduction to the discovery, distribution, pathogenic mechanism, in vivo biosynthesis, and in vitro artificial synthesis of AZA toxins. Additionally, it will summarize various detection methods employed over the past 20 years, along with their advantages and disadvantages. This effort will contribute to the future development of rapid detection technologies and the invention of detection devices for AZAs in marine environmental samples.
Assuntos
Toxinas Marinhas , Toxinas de Poliéter , Compostos de Espiro , Toxinas Marinhas/toxicidade , Compostos de Espiro/toxicidadeRESUMO
Based on previous empirical evidences and theoretical framework, sleep problems and non-suicidal self-injury (NSSI)/suicidal behavior may bidirectionally related to one another. However, this still needs to be examined through longitudinal research. Moreover, the mediating mechanisms accounting for their potential bidirectional relations have yet to be fully investigated. This study thus aimed to evaluate whether sleep problems and NSSI/suicidal behavior promoted each other directly or indirectly through the mediating roles of emotion regulation difficulties (ERD) and externalizing problems. A total of 1648 Chinese adolescents (48.12% boys; Mage = 13.69; SD = 0.82; Age range = 11-16 years old at T1) completed self-report measures on 3-time points across 1 year. Cross-lagged panel models were used to examine the focal longitudinal associations. Results revealed a predictive effect of sleep problems on NSSI and a positive bidirectional relation between sleep problems and suicidal behavior. Moreover, sleep problems exerted an indirect effect on NSSI through ERD, and vice versa. Additionally, both ERD and externalizing problems served as mediators in the pathway from suicidal behavior to sleep problems. This study disentangled the differential mediating roles of ERD and externalizing problems in the longitudinal associations between sleep problems and NSSI/suicidal behavior, which may help provide a more holistic theoretical framework through which to precisely identify key targets for early prevention and intervention of sleep problems and NSSI/suicidal behavior in adolescents.
Assuntos
Comportamento do Adolescente , Regulação Emocional , Comportamento Autodestrutivo , Transtornos do Sono-Vigília , Humanos , Adolescente , Masculino , Feminino , Comportamento Autodestrutivo/psicologia , Regulação Emocional/fisiologia , Transtornos do Sono-Vigília/psicologia , Criança , Comportamento do Adolescente/psicologia , Estudos Longitudinais , China , Ideação Suicida , AutorrelatoRESUMO
INTRODUCTION: Childhood maltreatment, peer victimization, and borderline personality traits have all been shown to be linked to suicidal risk. However, there remains a need to illuminate the possible direct and indirect pathways among them from a developmental perspective that could serve as intervention targets. This study thus aimed to investigate the direct and indirect relationships among developmental trajectories of childhood maltreatment, peer victimization, borderline personality feature, and suicidal risk in adolescents. METHODS: A total of 1648 Chinese adolescents (48.12% boys; Mage = 13.69; SD = 0.82) in junior middle schools completed self-report measures on three-time points across 1 year. Latent growth curve modeling was used to evaluate the direct and indirect relationships among the developmental trajectories of the aforementioned study variables. RESULTS: The developmental trajectories of childhood maltreatment, peer victimization, and borderline personality feature were positively and directly related to the developmental trajectory of suicidal risk; and the developmental trajectories of childhood maltreatment, peer victimization were indirectly related to the developmental trajectory of suicidal risk through the mediating effect of the developmental trajectory of borderline personality feature. CONCLUSIONS: The findings elucidated the direct and indirect longitudinal relationships among childhood maltreatment, peer victimization, borderline personality feature, and suicidal risk, highlighting that interventions should target childhood maltreatment, peer victimization, and borderline personality feature to decrease suicidal risk in adolescents with a developmental perspective.
Assuntos
Transtorno da Personalidade Borderline , Bullying , Maus-Tratos Infantis , Vítimas de Crime , Grupo Associado , Humanos , Adolescente , Masculino , Feminino , Maus-Tratos Infantis/psicologia , Maus-Tratos Infantis/estatística & dados numéricos , Bullying/estatística & dados numéricos , Bullying/psicologia , Transtorno da Personalidade Borderline/epidemiologia , Transtorno da Personalidade Borderline/psicologia , Transtorno da Personalidade Borderline/etiologia , Vítimas de Crime/psicologia , Vítimas de Crime/estatística & dados numéricos , China/epidemiologia , Ideação Suicida , Estudos Longitudinais , Criança , Fatores de Risco , AutorrelatoRESUMO
Triple-negative breast cancer (TNBC) makes up 15 % to 20 % of all breast cancer (BC) cases, and represents one of the most challenging malignancies to treat. For many years, chemotherapy has been the main treatment option for TNBC. Natural products isolated from marine organisms and terrestrial organisms with great structural diversity and high biochemical specificity form a compound library for the assessment and discovery of new drugs. In this review, we mainly focused on natural compounds and extracts (from marine and terrestrial environments) with strong anti-TNBC activities (IC50 <100â µM) and their possible mechanisms reported in the past six years (2015-2021).
Assuntos
Antineoplásicos Fitogênicos/farmacologia , Produtos Biológicos/farmacologia , Extratos Vegetais/farmacologia , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Apoptose/efeitos dos fármacos , Produtos Biológicos/química , Produtos Biológicos/isolamento & purificação , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Conformação Molecular , Extratos Vegetais/química , Extratos Vegetais/isolamento & purificação , Neoplasias de Mama Triplo Negativas/patologiaRESUMO
BACKGROUND: The deleterious effects of childhood maltreatment, emotion regulation difficulties (ERD), and externalizing problems (EP) on sleep problems has been established. Nevertheless, there is still a need to gain a deeper understanding of the potential direct and indirect mechanisms through which these crucial risk factors influence adolescents' sleep problems, particularly with a developmental perspective. This study thus aimed to examine the direct and indirect associations among developmental trajectories of the focal variables in adolescents. METHODS: A total of 1648 Chinese adolescents (48.12% boys; Mage = 13.69 years, SD = 0.82) completed self-report measures on 3 time points across 1 years. Latent growth curve modeling was used to examine the hypothesized models. RESULTS: Both the developmental trajectory of childhood maltreatment and the developmental trajectory of ERD/EP were positively and directly related to the developmental trajectory of sleep problems; and the developmental trajectory of childhood maltreatment was indirectly related to the developmental trajectory of sleep problems through the mediating effect of the developmental trajectory of ERD/EP. CONCLUSIONS: The findings elucidated the direct and indirect longitudinal associations among the focal variables, highlighting that interventions should target childhood maltreatment and ERD/EP to decrease sleep problems in adolescents with a developmental perspective.
Assuntos
Maus-Tratos Infantis , Regulação Emocional , Transtornos do Sono-Vigília , Masculino , Humanos , Adolescente , Feminino , Criança , Fatores de Risco , Autorrelato , Transtornos do Sono-Vigília/epidemiologiaRESUMO
BACKGROUND: Previous research established the associations between childhood trauma and psychosis, but the effects of childhood trauma on psychotic-like experiences (PLEs) among people living with HIV (PLWH) and the potential mediation mechanisms in these associations remain unclear. OBJECTIVE: This study aimed to investigate the effects of childhood trauma on PLEs, as well as the chain mediation roles of stigma and resilience in this relationship. Furthermore, we explored whether the aforementioned associations differed when hallucinatory experiences (HEs) and delusional experiences (DEs) were separately modeled. PARTICIPANTS AND SETTING: The sample included 333 outpatients participants (95.2 % males, Mage = 28.24 ± 7.12) living with HIV recruited from Hunan Province, China; and data were collected with a cross-sectional survey. METHOD: The hypothesized chain mediation models were examined using SPSS PROCESS macro 3.3 software. RESULTS: Various influencing mechanisms of childhood trauma on HEs and DEs were examined in this study. Our results showed that, (a) childhood trauma directly exerted negative effect on HEs, while the chain mediation effect of stigma and resilience were not statistically significant. Conversely, (b) childhood trauma exerted no direct influence on DEs but rather through the chain mediation effect of stigma and resilience. CONCLUSIONS: The identification of two different routes between that childhood trauma can have on HEs and DEs highlighted the importance of tailored prevention and intervention among PLWH with a history of childhood trauma.
Assuntos
Experiências Adversas da Infância , Infecções por HIV , Transtornos Psicóticos , Resiliência Psicológica , Estigma Social , Humanos , Masculino , Feminino , Adulto , Infecções por HIV/psicologia , Estudos Transversais , Adulto Jovem , Experiências Adversas da Infância/estatística & dados numéricos , China , Alucinações/etiologia , Delusões/etiologia , Pessoa de Meia-Idade , Adultos Sobreviventes de Eventos Adversos na Infância/estatística & dados numéricos , Adultos Sobreviventes de Eventos Adversos na Infância/psicologiaRESUMO
Bladder cancer (BLCA) is a prevalent malignancy of the urinary system, associated with a high recurrence rate and poor prognosis. FAM111B, which encodes a protein containing a trypsin-like cysteine/serine peptidase domain, has been implicated in the progression of various human cancers; however, its involvement in BLCA remains unclear. In this study, we investigated the expression of FAM111B gene in tumor tissues compared to para-tumor tissues using immunohistochemistry and observed a significantly higher FAM111B gene expression in tumor tissues. Furthermore, analysis of clinical characteristics indicated that the increased FAM111B gene expression correlated with lymphatic metastasis and reduced overall survival. To investigate its functional role, we employed FAM111B-knockdown BLCA cell models and performed cell proliferation, wound-healing, transwell, and flow cytometry assays. The results showed that decreased FAM111B gene expression inhibited proliferation and migration but induced apoptosis in BLCA cells. In vivo experiments further validated that FAM111B knockdown suppressed tumor growth. Overall, our findings suggest that FAM111B acts as an oncogene in BLCA, playing a critical role in tumorigenesis, progression, and metastasis of BLCA. In conclusion, we have demonstrated a strong correlation between the expression of FAM111B gene and the development, progression, and metastasis of bladder cancer (BLCA). Thus, FAM111B is an oncogene associated with BLCA and holds promise as a molecular target for future treatment of this cancer.
RESUMO
Previous research has investigated the associations among childhood maltreatment, self-control, and aggression among adolescents without distinguishing between-person effects from within-person effects. Thus, we evaluated the dynamic longitudinal associations among childhood maltreatment, self-control, and aggression, including whether self-control functioned as a mediator of the reciprocal relations between childhood maltreatment and aggression at the within-person level after disentangling between- and within-person associations. A sample of 2050 Chinese early adolescents (43.69% girls, Mage = 10.39 years, SD = 0.55, range = 9 to 12 years at T1) completed measures on 5 occasions across 2.5 years, using 6-month intervals. Random Intercept Cross-Lagged Panel Models were applied to disaggregate between- and within-person effects. RI-CLPMs analysis revealed that at the within-person level: (a) Childhood maltreatment and aggression bidirectionally predicted each other; (b) Childhood maltreatment and self-control bidirectionally predicted each other; (c) Aggression predicted subsequent self-control but not vice versa; (d) Childhood maltreatment did not indirectly predict aggression via self-control and vice versa; (e) Additionally, there were no gender differences observed in the longitudinal associations among childhood maltreatment, self-control and aggression. These findings advanced the literature by elucidating longitudinal associations among childhood maltreatment, self-control, and aggression at the within-person level, highlighting the significance of distinguishing between- and within-person effects in research informing the development of prevention and intervention programs aimed at reducing adolescent aggression.
Assuntos
Maus-Tratos Infantis , Autocontrole , Adolescente , Agressão , Criança , Feminino , Humanos , Lactente , Relações Interpessoais , MasculinoRESUMO
RATIONALE: Previous cross-sectional and unidirectional longitudinal studies have investigated the associations among perceived parental warmth, positivity, and depressive symptoms among children and adolescents without distinguishing between-person effects from within-person effects. OBJECTIVE: The current study aimed to examine the dynamic longitudinal associations among perceived parental warmth, positivity, and depressive symptoms, including whether positivity functioned as a mediator of the reciprocal relations between perceived maternal/paternal warmth and depressive symptoms at the within-person level encompassing middle childhood to early adolescence. METHODS: A sample of 3765 Chinese students (45.8% girls; M age = 9.92 years, SD = 0.72; range = 9-12 years at Time 1) completed self-report measures on 4 occasions across 2 years, using 6-month intervals. Random-Intercept Cross-Lagged Panel Models were employed to disentangle between- and within-person effects. RESULTS: (a) Perceived maternal/paternal warmth and depressive symptoms reciprocally and negatively predicted each other; (b) positivity and depressive symptoms reciprocally and negatively predicted each other; (c) perceived maternal/paternal warmth and positivity reciprocally and positively predicted each other; (d) depressive symptoms indirectly predicted perceived maternal/paternal warmth via positivity; (e) perceived maternal warmth displayed earlier and more stable effects on positivity and depressive symptoms than perceived paternal warmth; and (f), no childhood sex differences existed in the observed associations. CONCLUSIONS: These findings highlight the longitudinal within-person transactions among perceived parental warmth, positivity, and depressive symptoms, and the differential roles of perceived maternal/paternal warmth. These findings may help provide a potential theoretical framework through which to precisely identify objectives for early intervention.
Assuntos
Depressão , Relações Pais-Filho , Adolescente , Criança , Estudos Transversais , Depressão/epidemiologia , Pai , Feminino , Humanos , Lactente , Estudos Longitudinais , MasculinoRESUMO
BACKGROUND: Previous research has identified a significant, positive relation between childhood maltreatment and depressive symptoms. However, the findings required replication at the within-person level. Moreover, the mediating mechanism of locus of control accounting for their relations has yet to be fully evaluated. Thus, this study examined the dynamic longitudinal relations between childhood maltreatment and depressive symptoms including whether locus of control functioned as a mediator between them after separating between-person effects from within-person effects. METHODS: A sample of 4110 Chinese children (50.60% boys; Mage = 9.89 at Wave 1) covering the transitional period from middle childhood to early adolescence completed a package of self-report measures on 5 occasions across 2.5 years, using 6-month intervals. Random Intercept Cross-Lagged Panel Models were applied to disaggregate between- and within-person effects. Also, alternative Cross-Lagged Panel Models were applied. RESULTS: Locus of control played a mediating role in the reciprocal relations between childhood maltreatment and depressive symptoms at the within-person level. LIMITATIONS: Some limitations existed in the measures. Moreover, sexual abuse was not investigated in this study. CONCLUSIONS: The findings highlighted the mediating role of locus of control in the reciprocal relations between childhood maltreatment and depressive symptoms at the within-person level, suggesting that interventions targeted at promoting internal locus of control may help prevent the developmental pathway from childhood maltreatment to depressive symptoms and vice versa from middle childhood to early adolescence.
Assuntos
Maus-Tratos Infantis , Depressão , Adolescente , Criança , Feminino , Humanos , Controle Interno-Externo , MasculinoRESUMO
The vital functions of long noncoding (lnc)RNAs have been verified in gastric carcinoma (GC). However, as a novel cancerrelated lncRNA, the influence of leukemia inhibitory factor receptor antisense RNA 1 (LIFRAS1) in GC cell biological behaviors remains unreported. The present study explored the biological effects of lncRNA LIFRAS1 on GC progression. Reverse transcriptionquantitative PCR was performed to examine lncRNA LIFRAS1 expression in GC tissues and cells. Cell Counting Kit8, 5ethynyl2'deoxyuridine incorporation, cell wound healing and Transwell invasion assays were used to assess the functions of lncRNA LIFRAS1 in GC cell proliferation, migration and invasion. Additionally, associations among lncRNA LIFRAS1, microRNA (miR)4698 and microtubuleassociated tumor suppressor 1 (MTUS1) were investigated via bioinformatics software and a luciferase reporter system. In addition, western blotting was used to examine the expression of MEK and ERK. Decreased lncRNA LIFRAS1 expression was observed in GC tissues and cells. Upregulated lncRNA LIFRAS1 inhibited GC cell proliferation, migration and invasion. Upregulated miR4698 and downregulated MTUS1 were identified in GC tissues and cells. The inhibitory interaction between lncRNA LIFRAS1 and miR4698 was confirmed. Additionally, MTUS1 was predicted as a target gene of miR4698 positively regulated by lncRNA LIFRAS1. The MEK/ERK pathway was inhibited by lncRNA LIFRAS1 via regulating MTUS1. These findings revealed the inhibitory functions of lncRNA LIFRAS1 in GC cell proliferation, migration and invasion. The process was mediated via miR4698, MTUS1 and the MEK/ERK pathway.
Assuntos
Movimento Celular , Proliferação de Células , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , RNA Neoplásico/metabolismo , Neoplasias Gástricas/metabolismo , Linhagem Celular Tumoral , Humanos , MicroRNAs/genética , Invasividade Neoplásica , RNA Longo não Codificante/genética , RNA Neoplásico/genética , Neoplasias Gástricas/genética , Neoplasias Gástricas/patologiaRESUMO
This paper reviews the recent developments in the area of MEMS-based probe recording technology. Various state-of-the-art scanning probe microscope (SPM) based techniques are briefly introduced, followed by the description of system approaches of MEMS-based probe recording technology and the basic MEMS-based actuation mechanism. Subsequently, current research status in developing MEMS-based probe recording technology with emphasis on storage architecture, MEMS access systems, probe recording mechanisms, and media for terabit per square inch recording density, is reviewed. Lastly, potential research topics and prospects for MEMS-based probe recording technology development are discussed.
Assuntos
Dispositivos de Armazenamento em Computador , Eletroquímica/métodos , Armazenamento e Recuperação da Informação , Magnetismo , Nanotecnologia/métodos , Algoritmos , Desenho de Equipamento , Microscopia de Força Atômica , Microscopia de Varredura por Sonda , Modelos Teóricos , Eletricidade Estática , Fatores de TempoRESUMO
OBJECTIVE: To test the reliability and validity of Meaningful Life Measure-Chinese Revised (MLM-CR) in Chinese college students. METHODS: A total of 1035 college students were evaluated with MLM-CR, Satisfaction with Life Scale (SWLS), Purpose in Life (PIL) and Patient Health Questionnaire-2 (PHQ-2), and 120 of the students were examined with PIL-SF twice. RESULTS: All the items in MLM-CR had good discrimination indexes (r=0.753-0.838, P<0.001). Confirmatory factor analysis confirmed the hypothesized five-factor model of MLM-CR (Χ2/df=3.4, GFI=0.946, AGFI=0.924, RMR=0.069, NFI=0.953, CFI=0.966, RMSEA=0.048). The total internal consistency reliability of MLM-CR was 0.942, and the alpha coefficients of the 5 dimensions ranged from 0.782 to 0.877; the total split-half reliability was 0.920, and the split-half reliability of the 5 dimensions ranged from 0.752 to 0.830; the total test-retest reliability was 0.871, and the test-retest reliability of the 5 dimensions ranged from 0.783 to 0.805. The criterion validity of MLM-CR in correlation with SWLS, PIL and PHQ-2 was 0.66, 0.755 and -0.388, respectively (P<0.01). The Average score of MLM-CR of the college students was 5.20∓0.90, and the scores were significantly higher in female students than in the male students (P<0.001). CONCLUSION: MLM-CR has good psychometric properties for application in comprehensive evaluation of personal meaning in life.
Assuntos
Psicometria , Inquéritos e Questionários , Povo Asiático , China , Análise Fatorial , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes , EstudantesRESUMO
A photosensitive self-oscillating gel that incorporates the Belousov-Zhabotinsky reaction can undergo rhythmic mechanical oscillations. We exploit the dependence of the oscillation frequency on light intensity to generate both photophobic and phototropic movement of the gel under differential illumination. Our findings may be used in designing intelligent sensors that can execute biomimetic behaviours.