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1.
Small ; 20(16): e2307246, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38039499

RESUMO

Perovskite solar cells (PSCs) with a booming high power conversion efficiency (PCE) are on their road toward industrialization. A proper design of the counter electrode (CE) with low cost, high conductivity, chemical stability, and good interface contact with the other functional layer atop the perovskite layer is vital for the overall performance of PSCs. Herein, the application of titanium nitride (TiN) is reported as a conductive medium for the printable CE in hole-conductor-free mesoscopic PSCs. TiN improves the conductivity of the CE and reduces the resistivity from 20 to 10 mΩ∙cm. TiN also improves the wettability of the CE with perovskite and enhances the back interface contact, which promotes charge collection. On the other hand, TiN is chemically stable during processing and undergoes no distinguishable chemical reaction with halide perovskite. Devices with TiN as the conductive media in the CE deliver a champion PCE of 19.01%. This work supplies a considerable choice for the CE design of PSCs toward industrial applications.

2.
Prev Med ; 180: 107893, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38342383

RESUMO

PURPOSE: The association between sleep and myopia in children and adolescents has been reported, yet it remains controversial and inconclusive. This study aimed to investigate the influence of different sleep traits on the risk of myopia using meta-analytical and Mendelian randomization (MR) techniques. METHODS: The literature search was performed in August 31, 2023 based on PubMed, Embase, Web of Science, and Cochrane library. The meta-analysis of observational studies reporting the relationship between sleep and myopia was conducted. MR analyses were carried out to assess the causal impact of genetic pre-disposition for sleep traits on myopia. RESULTS: The results of the meta-analysis indicated a significant association between the risk of myopia and both short sleep duration [odds ratio (OR) = 1.23, 95% confidence interval (CI) = 1.08-1.42, P = 0.003] and long sleep duration (OR = 0.75, 95% CI = 0.66-0.86, P < 0.001). MR analyses revealed no significant causal associations of genetically determined sleep traits with myopia, including chronotype, sleep duration, short sleep duration and long sleep duration (all P > 0.05). CONCLUSIONS: No evidence was found to support a causal relationship between sleep traits and myopia. While sleep may not independently predict the risk of myopia, the potential impact of sleep on the occurrence and development of myopia cannot be disregarded.


Assuntos
Análise da Randomização Mendeliana , Miopia , Criança , Adolescente , Humanos , Sono/genética , Miopia/epidemiologia , Miopia/genética , Razão de Chances , Fenótipo , Estudo de Associação Genômica Ampla
3.
Int J Mol Sci ; 25(2)2024 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-38255972

RESUMO

Congenital stationary night blindness (CSNB) is a genetically heterogeneous inherited retinal disorder, caused by over 300 mutations in 17 different genes. While there are numerous fly models available for simulating ocular diseases, most are focused on mimicking retinitis pigmentosa (RP), with animal models specifically addressing CSNB limited to mammals. Here, we present a CSNB fly model associated with the mtt gene, utilizing RNA interference (RNAi) to silence the mtt gene in fly eyes (homologous to the mammalian GRM6 gene) and construct a CSNB model. Through this approach, we observed significant defects in the eye structure and function upon reducing mtt expression in fly eyes. This manifested as disruptions in the compound eye lens structure and reduced sensitivity to light responses. These results suggest a critical role for mtt in the function of fly adult eyes. Interestingly, we found that the mtt gene is not expressed in the photoreceptor neurons of adult flies but is localized to the inner lamina neurons. In summary, these results underscore the crucial involvement of mtt in fly retinal function, providing a framework for understanding the pathogenic mechanisms of CSNB and facilitating research into potential therapeutic interventions.


Assuntos
Cristalino , Retinose Pigmentar , Animais , Drosophila/genética , Retina , Retinose Pigmentar/genética
4.
FASEB J ; 36(3): e22084, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-35107844

RESUMO

Chronic kidney disease (CKD), a disease involving damage to the kidney structure and function, is a global public health problem. Tubulointerstitial fibrosis (TIF) is both an inevitable pathological change in individuals with CKD and a driving force in the progression of renal fibrosis. Nicotinamide N-methyltransferase (NNMT) and its metabolite 1-methylnicotinamide (MNAM) have been shown to protect against lipotoxicity-induced kidney tubular injury. However, the biological roles of NNMT and MNAM in regulating TIF remain elusive. This study aimed to investigate the protective effect of NNMT and MNAM on TIF and the mechanisms involved. We explored the functions and mechanisms of NNMT and MNAM in TIF, as well as the interaction between NNMT and MNAM, using unilateral ureteral obstruction (UUO) mice and cultured mouse tubular epithelial cells (mTECs) stimulated with transforming growth factor-ß1 (TGF-ß1). Several important findings were obtained as follows: (1) NNMT expression was upregulated in the kidneys of UUO mice and TGF-ß1-induced mTECs, and this upregulation was proposed to be a protective compensatory response to TIF. (2) MNAM was a potentially effective antifibrotic and anti-inflammatory medication in UUO mice. (3) The antifibrotic effect of NNMT overexpression was exerted by increasing the concentration of MNAM. (4) The renoprotective role of MNAM depended on the selective blockade of the interaction of Smad3 with TGFß receptor I. Overall, our study shows that NNMT is involved in the development and progression of CKD and that its metabolite MNAM may be a novel inhibitor of the TGF-ß1/Smad3 pathway with great therapeutic potential for CKD.


Assuntos
Fibrose/metabolismo , Niacinamida/análogos & derivados , Nicotinamida N-Metiltransferase/metabolismo , Insuficiência Renal Crônica/metabolismo , Transdução de Sinais/fisiologia , Proteína Smad3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Animais , Células Cultivadas , Rim/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Niacinamida/metabolismo , Obstrução Ureteral/metabolismo
5.
Langmuir ; 39(33): 11491-11509, 2023 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-37535849

RESUMO

The phase behavior of binary blends of diblock copolymers has been examined extensively in the past decades. Experimental and theoretical studies have demonstrated that mixing two different block copolymers provides an efficient and versatile route to regulate their self-assembled morphologies. A good understanding of the principles governing the self-assembly of block copolymer blends has been obtained from the study of A1B1/A2B2 diblock copolymer blends. The second (A2B2) diblocks could act synergistically as fillers and cosurfactants to regulate the domain size and interfacial properties, resulting in the formation of ordered phases not found in the parent (A1B1 or A2B2) diblock copolymer melts. The study of A1B1/A2B2 block copolymer blends further provides a solid foundation for future research on more complex block copolymer blends.

6.
Sensors (Basel) ; 23(13)2023 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-37447797

RESUMO

Sudden cardiac death is a sudden and highly fatal condition. Implementing high-quality emergency cardiopulmonary resuscitation (CPR) early on is an effective rescue method for this disease. However, the rescue steps of CPR are complicated and difficult to remember, and the quantitative indicators are difficult to control, which leads to a poor quality of CPR emergency actions outside the hospital setting. Therefore, we have developed CPR emergency equipment with a multisensory feedback function, aiming to guide rescuers in performing CPR through visual, auditory, and tactile interaction. This equipment consists of three components: first aid clothing, an audio-visual integrated terminal, and a vital sign detector. These three components are based on a micro-power WiFi-Mesh network, enabling the long-term wireless transmission of the multisensor data. To evaluate the impact of the multisensory feedback CPR emergency equipment on nonprofessionals, we conducted a controlled experiment involving 32 nonmedical subjects. Each subject was assigned to either the experimental group, which used the equipment, or the control group, which did not. The main evaluation criteria were the chest compression (CC) depth, the CC rate, the precise depth of the CC ratio (5-6 cm), and the precise rate of the CC ratio -(100-120 times/min). The results indicated that the average CC depth in the experimental group was 51.5 ± 1.3 mm, which was significantly better than that of the control group (50.2 ± 2.2 mm, p = 0.012). Moreover, the average CC rate in the experimental group (110.1 ± 6.2 times/min) was significantly higher than that of the control group (100.4 ± 6.6 times/min) (p < 0.001). Compared to the control group (66.37%), the experimental group showed a higher proportion of precise CC depth (82.11%), which is closer to the standard CPR rate of 100%. In addition, the CC ratio of the precise rate was 93.75% in the experimental group, which was significantly better than that of 56.52% in the control group (p = 0.024). Following the experiment, the revised System Availability Scale (SUS) was utilized to evaluate the equipment's usability. The average total SUS score was 78.594, indicating that the equipment's acceptability range was evaluated as 'acceptable', and the overall adjective rating was 'good'. In conclusion, the multisensory feedback CPR emergency equipment significantly enhances the CC performance (CC depth, CC rate, the precise depth of CC ratio, the precise rate of CC ratio) of nonprofessionals during CPR, and the majority of participants perceive the equipment as being easy to use.


Assuntos
Reanimação Cardiopulmonar , Compressão de Dados , Humanos , Primeiros Socorros , Retroalimentação , Hospitais , Manequins
7.
Int J Mol Sci ; 24(22)2023 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-38003249

RESUMO

The aim of this study was to investigate NAD+/NADH redox regulation in astrocytes by Ginsenoside Rb1 subjected to oxygen-glucose deprivation/reoxygenation (OGD/R) and to reveal the neuroprotective mechanism of ginseng. Neonatal mouse brain was used to culture primary astrocytes. The third generation of the primary astrocytes was used for the experiments. OGD/R was introduced by culturing the cells in a glucose-free media under nitrogen for 6 h followed by a regular culture for 24 h. Ginsenoside Rb1 attenuated OGD/R-induced astrocyte injury in a dose-dependent manner. It improved the mitochondrial function of OGD/R astrocytes indicated by improving mitochondrial distribution, increasing mitochondrial membrane potential, and enhancing mitochondrial DNA copies and ATP production. Ginsenoside Rb1 significantly lifted intracellular NAD+/NADH, NADPH/NADP+, and GSH/GSSG in OGD/R astrocytes. It inhibited the protein expression of both PARP1 and CD38, while attenuating the SIRT1 drop in OGD/R cells. In line with its effects on PARP1, Ginsenoside Rb1 significantly reduced the expression of poly-ADP-ribosylation (PARylation) proteins in OGD/R cells. Ginsenoside Rb1 also significantly increased the expression of NAMPT and NMNAT2, both of which are key players in NAD/NADH synthesis. The results suggest that the regulation of NAD+/NADH redox involves the protective effects of ginsenoside Rb1 against OGD/R-induced astrocyte injury.


Assuntos
NAD , Oxigênio , Camundongos , Animais , Oxigênio/metabolismo , NAD/metabolismo , Astrócitos/metabolismo , Glucose/metabolismo , Células Cultivadas , Oxirredução
8.
FASEB J ; 35(9): e21789, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34383983

RESUMO

Normal pregnancy is essential for human reproduction. However, BaP (benzo(a)pyrene) and its metabolite BPDE (benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide) could cause dysfunctions of human trophoblast cells and might further induce miscarriage. Yet, the underlying mechanisms remain largely unknown. Herein, we identified a novel upregulated lnc-HZ04 and a novel downregulated miR-hz04 in villous tissues of unexplained recurrent miscarriage (RM) relative to those in healthy control tissues and also in BPDE-treated human trophoblast cells. Lnc-HZ04 directly and specifically bound with miR-hz04, diminished the reduction effects of miR-hz04 on IP3 R1 mRNA expression level and on IP3 R1 mRNA stability, and then activated the Ca2+ -mediated IP3 R1 /p-CaMKII/SGCB pathway, which further promoted trophoblast cell apoptosis. The miR-hz04 target site on lnc-HZ04 played crucial roles in these regulations. In normal trophoblast, relatively less lnc-HZ04 and more miR-hz04 suppressed this apoptosis pathway and gave normal pregnancy. After exposure to BPDE or in RM tissues, p53 was upregulated, which might promote p53-mediated lnc-HZ04 transcription. Relatively more lnc-HZ04 and less miR-hz04 activated this apoptosis pathway and might further induce miscarriage. BaP could also induce mice miscarriage by upregulating its corresponding murine apoptosis pathway. Therefore, BPDE-induced apoptosis of human trophoblast cells was associated with the occurrence of miscarriage. This work discovered the regulation roles of lnc-HZ04 and miR-hz04 and provided scientific and clinical understanding of the occurrence of unexplained miscarriage.


Assuntos
Aborto Habitual/genética , Apoptose/genética , MicroRNAs/genética , RNA Longo não Codificante/genética , Transdução de Sinais/genética , Trofoblastos/metabolismo , Regulação para Cima/genética , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/farmacologia , Aborto Habitual/tratamento farmacológico , Animais , Apoptose/efeitos dos fármacos , Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Linhagem Celular , Regulação para Baixo/efeitos dos fármacos , Regulação para Baixo/genética , Feminino , Humanos , Receptores de Inositol 1,4,5-Trifosfato/genética , Camundongos , Camundongos Endogâmicos C57BL , Gravidez , Sarcoglicanas/genética , Transdução de Sinais/efeitos dos fármacos , Trofoblastos/efeitos dos fármacos , Regulação para Cima/efeitos dos fármacos
9.
Cell Biol Toxicol ; 38(6): 1137-1157, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-35038060

RESUMO

Approximately 15-25% pregnant women end with miscarriage in the world. Environmental BaP (benzo(a)pyrene) and its terminal metabolite BPDE (benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide) may result in the dysfunctions of trophoblast cells, which might further lead to RM (recurrent miscarriage). However, potential mechanisms remain unelucidated. In this work, we identified a novel lnc-HZ05 highly expressed and a novel miR-hz05 lowly expressed in both trophoblast cells exposed to BPDE and human RM tissues. MiR-hz05 reduces FOXO3a mRNA level by weakening its mRNA stability. Lnc-HZ05 increases the expression of FOXO3a by acting as a ceRNA for miR-hz05, and then increases P21 level and reduces CDK2 level. Thus, cell cycle is arrested at G0/G1 phase and trophoblast proliferation is inhibited. Lnc-HZ05 harboring wild-type binding site for miR-hz05, but not its mutant site, could upregulate FOXO3a expression. In normal trophoblast cells, relatively less lnc-HZ05 and more miR-hz05 activate FOXO3a/P21/CDK2 pathway and promote trophoblast proliferation, giving normal pregnancy. In RM tissues and BPDE-treated human trophoblast cells, lnc-HZ05 is increased and miR-hz05 is reduced, both of which suppress this pathway and inhibit cell proliferation, and finally lead to miscarriage. Thus, lnc-HZ05 and miR-hz05 simultaneously regulate cell cycle and proliferation of BPDE-exposed trophoblast cells and miscarriage, providing new perspectives and clinical understandings in the occurrence of unexplained miscarriage.


Assuntos
7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido , Aborto Espontâneo , MicroRNAs , RNA Longo não Codificante , Feminino , Humanos , Gravidez , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/toxicidade , Aborto Espontâneo/genética , Aborto Espontâneo/metabolismo , Benzo(a)pireno/toxicidade , Linhagem Celular , Movimento Celular , Proliferação de Células/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Trofoblastos/metabolismo , RNA Longo não Codificante/genética
10.
Cell Biol Toxicol ; 38(2): 291-310, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-33864160

RESUMO

Increasing evidences have shown that pregnant women might miscarry after exposure with environmental BaP (benzo(a)pyrene). Additionally, BPDE (benzo(a)pyren-7,8-dihydrodiol-9,10-epoxide), the ultimate metabolite of BaP, could induce dysfunctions of human trophoblast cells. However, it is rarely correlated between miscarriage and trophoblast dysfunctions. Moreover, their underlying mechanisms are still largely unidentified. In this study, a novel lncRNA (long non-coding RNA), lnc-HZ08, was identified to be highly expressed in human recurrent miscarriage (RM) tissues and in BPDE-treated human trophoblast cells. Lnc-HZ08 acts as a RNA scaffold to interact with both PI3K and its ubiquitin ligase CBL (Cbl proto-oncogene), enhances their protein interactions, and promotes PI3K ubiquitin degradation. In RM tissues and BPDE-treated trophoblast cells, DNA methylation level in lnc-HZ08 promoter region was reduced, which promotes estrogen receptor 1 (ER)-mediated lnc-HZ08 transcription. Subsequently, this upregulated lnc-HZ08 downregulated PI3K level, suppressed PI3K/p-AKT/p-P21/CDK2 pathway, and thus weakened proliferation, migration, and invasion of human trophoblast cells, which further induces miscarriage. These results may provide novel scientific and clinical insights in the occurrence of unexplained miscarriage. A novel lncRNA (lnc-HZ08) regulates the functions of human trophoblast cells and affects miscarriage. Lnc-HZ08 promotes PI3K ubiquitin degradation by enhancing CBL and PI3K interactions, downregulates PI3K/p-AKT/p-P21/CDK2 pathway, and weakens proliferation, migration, and invasion of trophoblast cells. BPDE exposure reduces the DNA methylation level in lnc-HZ08 promoter region and promotes estrogen receptor 1 (ER)-mediated lnc-HZ08 transcription. The suppressed PI3K/p-AKT/p-P21/CDK2 pathway regulated by increased lnc-HZ08 is associated with miscarriage. These results provide novel insights in the occurrence of unexplained miscarriage. Graphical Headlights • Lnc-HZ08 downregulates PI3K/p-AKT/p-P21/CDK2 pathway to suppress proliferation, migration, and invasion of human trophoblast cells, and affects miscarriage. • Lnc-HZ08 acts as a RNA scaffold to enhance the protein interaction of PI3K and its ubiquitin ligase CBL, which increases PI3K ubiquitination and degradation. • Lnc-HZ08 transcription is associated with DNA methylation on its promoter region and transcription factor ER.


Assuntos
Aborto Espontâneo , RNA Longo não Codificante , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/metabolismo , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido/farmacologia , Aborto Espontâneo/genética , Aborto Espontâneo/metabolismo , Movimento Celular , Receptor alfa de Estrogênio/metabolismo , Feminino , Humanos , Ligases/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Gravidez , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Trofoblastos/metabolismo , Ubiquitina/metabolismo
11.
J Cell Mol Med ; 25(16): 7809-7824, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34180121

RESUMO

Intracerebral hemorrhage (ICH) can induce intensively oxidative stress, neuroinflammation, and brain cell apoptosis. However, currently, there is no highly effective treatment available. Puerarin (PUE) possesses excellent neuroprotective effects by suppressing the NF-κB pathway and activating the PI3K/Akt signal, but its role and related mechanisms in ICH-induced early brain injury (EBI) remain unclear. In this study, we intended to observe the effects of PUE and molecular mechanisms on ICH-induced EBI. ICH was induced in rats by collagenase IV injection. PUE was intraperitoneally administrated alone or with simultaneously intracerebroventricular injection of LY294002 (a specific inhibitor of the PI3K/Akt signal). Neurological deficiency, histological impairment, brain edema, hematoma volume, blood-brain barrier destruction, and brain cell apoptosis were evaluated. Western blot, immunohistochemistry staining, reactive oxygen species (ROS) measurement, and enzyme-linked immunosorbent assay were performed. PUE administration at 50 mg/kg and 100 mg/kg could significantly reduce ICH-induced neurological deficits and EBI. Moreover, PUE could notably restrain ICH-induced upregulation of the NF-κB pathway, pro-inflammatory cytokines, ROS level, and apoptotic pathway and activate the PI3K/Akt signal. However, LY294002 delivery could efficaciously weaken these neuroprotective effects of PUE. Overall, PUE could attenuate ICH-induced behavioral defects and EBI possibly by PI3K/Akt signal stimulation-mediated inhibition of the NF-κB pathway, and this made PUE a potential candidate as a promising therapeutic option for ICH-induced EBI.


Assuntos
Lesões Encefálicas/tratamento farmacológico , Hemorragia Cerebral/complicações , Isoflavonas/farmacologia , NF-kappa B/metabolismo , Estresse Oxidativo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Lesões Encefálicas/etiologia , Lesões Encefálicas/metabolismo , Lesões Encefálicas/patologia , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/patologia , Modelos Animais de Doenças , Masculino , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais , Vasodilatadores/farmacologia
12.
Cell Biol Toxicol ; 37(6): 951-970, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-33566220

RESUMO

Normal pregnancy is essential for human reproduction. However, environmental BaP (benzo(a)pyrene) and its metabolite BPDE (benzo(a)pyrene-7,8-dihydrodiol-9,10-epoxide) induce dysfunctions of human trophoblastic cells, which could further result in miscarriage. Yet, the molecular mechanisms remain poorly understood. In this work, a novel lnc-HZ03 and a novel miR-hz03 were identified. Both lnc-HZ03 and miR-hz03 were highly expressed in human recurrent miscarriage villous tissues and in BPDE-exposed trophoblastic cells. Lnc-HZ03 and miR-hz03 upregulated each other, forming a positive feedback loop. MiR-hz03 could also upregulate p53 level by enhancing its mRNA stability. Both lnc-HZ03 and p53 mRNA contained the target site for miR-hz03 and could directly interact with miR-hz03. It was this target site instead of its mutant on lnc-HZ03 that regulated p53 expression. Subsequently, the upregulated p53 facilitated SAT1 transcription and enhanced SAT1-catalyzed spermine metabolism, which further resulted in trophoblastic cell apoptosis and induced miscarriage. All together, the p53/SAT1 pathway upregulated by lnc-HZ03 and miR-hz03 could promote BPDE-induced human trophoblastic cell apoptosis and the occurrence of miscarriage, shedding novel light on the causes of miscarriage. Graphical abstract Lnc-HZ03 and miR-hz03 regulate the occurrence of recurrent miscarriage (RM). In human trophoblastic cells, lnc-HZ03 upregulates miR-hz03 level. MiR-hz03 increases the RNA stability of lnc-HZ03 and p53 mRNA. P53 promotes SAT1 transcription and reduces its cellular spermine content, resulting in cell apoptosis. Under normal conditions, lnc-HZ03/miR-hz03 and p53/SAT1 pathways are downregulated, maintaining normal pregnancy. After exposure to BPDE, lnc-HZ03/miR-hz03 and p53/SAT1 pathways are upregulated and finally induce miscarriage.


Assuntos
Aborto Espontâneo , MicroRNAs , 7,8-Di-Hidro-7,8-Di-Hidroxibenzo(a)pireno 9,10-óxido , Aborto Espontâneo/induzido quimicamente , Aborto Espontâneo/genética , Apoptose , Feminino , Humanos , MicroRNAs/genética , Gravidez , Proteína Supressora de Tumor p53/genética
13.
J Biol Chem ; 293(3): 830-846, 2018 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-29187598

RESUMO

Recent discoveries of broadly neutralizing antibodies (bnAbs) in HIV-1-infected individuals have led to the identification of several major "vulnerable sites" on the HIV-1 envelope (Env) glycoprotein. These sites have provided precise targets for HIV-1 vaccine development, but identifying and utilizing many of these targets remain technically challenging. Using a yeast surface display-based approach, we sought to identify epitope-focused antigenic domains (EADs) containing one of the "vulnerable sites," the CD4-binding site (CD4bs), through screening and selection of a combinatorial antigen library of the HIV-1 envelope glycoprotein with the CD4bs bnAb VRC01. We isolated multiple EADs and found that their trimeric forms have biochemical and structural features that preferentially bind and activate B cells that express VRC01 in vitro More importantly, these EADs could induce detectable levels of neutralizing antibodies against genetically related autologous and heterologous subtype B viruses in guinea pigs. Our results demonstrate that an epitope-focused approach involving a screen of a combinatorial antigen library is feasible. The EADs identified here represent a promising collection of possible targets in the rational design of HIV-1 vaccines and lay the foundation for harnessing the specific antigenicity of CD4bs for protective immunogenicity in vivo.


Assuntos
Anticorpos Neutralizantes/imunologia , Antígenos CD4/imunologia , HIV-1/metabolismo , Animais , Sítios de Ligação , Cobaias , HIV-1/imunologia , Humanos , Ligação Proteica , Proteínas do Envelope Viral/imunologia , Proteínas do Envelope Viral/metabolismo , Proteínas Virais/imunologia , Proteínas Virais/metabolismo
14.
Chem Res Toxicol ; 32(5): 840-849, 2019 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-30938985

RESUMO

N6-methyladenine (6mA), a newly identified epigenetic modification, plays important roles in regulation of various biological processes. However, the effect of 6mA on DNA replication has been little addressed. In this work, we investigated how 6mA affected DNA replication by DNA polymerase of Pseudomonas aeruginosa Phage PaP1 (gp90 exo-). The presence of 6mA, as well as its intermediate hypoxanthine (Hyp), inhibited DNA replication by gp90 exo-. The 6mA reduced dTTP incorporation efficiency by 10-fold and inhibited next-base extension efficiency by 100-fold. Differently, dCTP was preferentially incorporated opposite Hyp among four dNTPs. Gp90 exo- reduced the extension priority beyond the 6mA:T pair rather than the 6mA:C mispair and preferred to extend beyond Hyp:C rather than the Hyp:T pair. Incorporation of dTTP opposite 6mA and dCTP opposite Hyp showed fast burst phases. The burst rate and burst amplitude were both reduced for 6mA compared with unmodified A. Moreover, the total incorporation efficiency ( kpol/ Kd,dNTP) was decreased for dTTP incorporation opposite 6mA and dCTP incorporation opposite Hyp compared with dTTP incorporation opposite A. 6mA reduced the incorporation rate ( kpol), and Hyp increased the dissociation constant ( Kd,dNTP). However, 6mA or Hyp on template did not affect the binding of DNA polymerase to DNA in binary or ternary complexes. This work provides new insight into the inhibited effects of epigenetic modification of 6mA on DNA replication in PaP1.


Assuntos
Adenina/metabolismo , Bacteriófagos/enzimologia , Replicação do DNA , DNA Polimerase Dirigida por DNA/metabolismo , DNA/metabolismo , Proteínas Virais/metabolismo , Adenina/análogos & derivados , DNA/química , Espectroscopia de Ressonância de Spin Eletrônica , Cinética
15.
Mutagenesis ; 34(4): 355-361, 2019 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-31318416

RESUMO

Abasic site as a common DNA lesion blocks DNA replication and is highly mutagenic. Protein interactions in T7 DNA replisome facilitate DNA replication and translesion DNA synthesis. However, bypass of an abasic site by T7 DNA replisome has never been investigated. In this work, we used T7 DNA replisome and T7 DNA polymerase alone as two models to study DNA replication on encountering an abasic site. Relative to unmodified DNA, abasic site strongly inhibited primer extension and completely blocked strand-displacement DNA synthesis, due to the decreased fraction of enzyme-DNA productive complex and the reduced average extension rates. Moreover, abasic site at DNA fork inhibited the binding of DNA polymerase or helicase onto fork and the binding between polymerase and helicase at fork. Notably and unexpectedly, we found DNA polymerase alone bypassed an abasic site on primer/template (P/T) substrate more efficiently than did polymerase and helicase complex bypass it at fork. The presence of gp2.5 further inhibited the abasic site bypass at DNA fork. Kinetic analysis showed that this inhibition at fork relative to that on P/T was due to the decreased fraction of productive complex instead of the average extension rates. Therefore, we found that protein interactions in T7 DNA replisome inhibited the bypass of DNA lesion, different from all the traditional concept that protein interactions or accessory proteins always promote DNA replication and DNA damage bypass, providing new insights in translesion DNA synthesis performed by DNA replisome.


Assuntos
Replicação do DNA , DNA Polimerase Dirigida por DNA/metabolismo , Complexos Multienzimáticos/metabolismo , DNA/genética , DNA/metabolismo , DNA Helicases/metabolismo , Cinética , Ligação Proteica
16.
J Sci Food Agric ; 98(2): 787-791, 2018 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-28677852

RESUMO

BACKGROUND: Sodium dehydroacetate (Na-DHA) is a food and feed additive with antimicrobial effects. There is little information on Na-DHA residue levels in foods derived from animals. In this study, Na-DHA residue levels in swine tissues were determined by HLPC, and the pharmacokinetics of Na-DHA in tissues were determined. RESULTS: The Na-DHA residue levels in swine tissues were <1.2 mg kg-1 at different withdrawal time after thirty-two Duroc × Landrace × Yorkshire pigs were administered 200 mg Na-DHA kg-1 through the feed for 30 days. In decreasing order of Na-DHA residue levels, the tissues were kidney > liver > muscle > fat. The pharmacokinetics of Na-DHA followed a binomial regression model, and the half-time of Na-DHA in swine tissues was 9.07 days for kidney, 7.19 days for liver, 6.66 days for muscle, and 5.39 days for fat tissue. The accuracy of the HPLC method for Na-DHA determination ranged from 80.18% to 91.33% recovery, with coefficients of variation <6.4%, limit of detection of 0.08 mg kg-1 , and limit of quantification of 0.2 mg kg-1 . CONCLUSION: Na-DHA included at 200 mg kg-1 in a swine diet is a safe feed additive based on residue elimination and ADI values reported. © 2017 Society of Chemical Industry.


Assuntos
Ração Animal/análise , Resíduos de Drogas/farmacocinética , Conservantes de Alimentos/farmacocinética , Pironas/farmacocinética , Suínos , Tecido Adiposo/química , Tecido Adiposo/metabolismo , Animais , Meia-Vida , Rim/química , Rim/metabolismo , Fígado/química , Fígado/metabolismo , Músculo Esquelético/química , Músculo Esquelético/metabolismo
17.
Insect Sci ; 31(2): 503-523, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37632209

RESUMO

Royal jelly (RJ) is a biologically active substance secreted by the hypopharyngeal and mandibular glands of worker honeybees. It is widely claimed that RJ reduces oxidative stress. However, the antioxidant activity of RJ has mostly been determined by in vitro chemical detection methods or by external administration drugs that cause oxidative stress. Whether RJ can clear the endogenous production of reactive oxygen species (ROS) in cells remains largely unknown. Here, we systematically investigated the antioxidant properties of RJ using several endogenous oxidative stress models of Drosophila. We found that RJ enhanced sleep quality of aging Drosophila, which is decreased due to an increase of oxidative damage with age. RJ supplementation improved survival and suppressed ROS levels in gut cells of flies upon exposure to hydrogen peroxide or to the neurotoxic agent paraquat. Moreover, RJ supplementation moderated levels of ROS in endogenous gut cells and extended lifespan after exposure of flies to heat stress. Sleep deprivation leads to accumulation of ROS in the gut cells, and RJ attenuated the consequences of oxidative stress caused by sleep loss and prolonged lifespan. Mechanistically, RJ prevented cell oxidative damage caused by heat stress or sleep deprivation, with the antioxidant activity in vivo independent of Keap1/Nrf2 signaling. RJ supplementation activated oxidoreductase activity in the guts of flies, suggesting its ability to inhibit endogenous oxidative stress and maintain health, possibly in humans.


Assuntos
Antioxidantes , Proteínas de Drosophila , Humanos , Abelhas , Animais , Antioxidantes/farmacologia , Fator 2 Relacionado a NF-E2/metabolismo , Drosophila/metabolismo , Espécies Reativas de Oxigênio , Proteína 1 Associada a ECH Semelhante a Kelch , Privação do Sono , Ácidos Graxos , Estresse Oxidativo , Oxirredutases
18.
Behav Sci (Basel) ; 14(6)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38920809

RESUMO

During the COVID-19 pandemic, many countries and regions experienced a surge in online learning, but the public complained about and questioned its effectiveness. One of the most important reasons for this was the inadequate metacognitive abilities of adolescents. Studies in learning sciences have identified various inefficient learning behaviors among students in online learning, including help abuse, help avoidance, and wheel spinning; all closely related to metacognition. Despite concerns about ecological validity, researchers in psychology have proposed the agenda-based regulation framework, the COPES model, and MAPS model, which may help explain the inefficient learning behaviors among adolescents in online learning. Future studies should aim to verify these theoretical frameworks within the context of online learning and elucidate the causes of inefficient learning behaviors; the design and optimization of online learning systems should be informed by theories in cognitive psychology.

19.
Neuroscience ; 545: 158-170, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38513765

RESUMO

Thioredoxin-reductase 2 (Txnrd2) belongs to the thioredoxin-reductase family of selenoproteins and is a key antioxidant enzyme in mammalian cells to regulate redox homeostasis. Here, we reported that Txnrd2 exerted a major influence in brain damage caused by Intracerebral hemorrhage (ICH) by suppressing endoplasmic reticulum (ER) stress oxidative stress and via Trx2/Prx3 pathway. Furthermore, we demonstrated that pharmacological selenium (Se) rescued the brain damage after ICH by enhancing Txnrd2 expression. Primarily, expression and localization of Txnrd2, Trx2 and Prx3 were determined in collagenase IV-induced ICH model. Txnrd2 was then knocked down using siRNA interference in rats which were found to develop more severe encephaledema and neurological deficits. Mechanistically, we observed that loss of Txnrd2 leads to increased lipid peroxidation levels and ER stress protein expression in neurons and astrocytes. Additionally, it was revealed that Se effectively restored the expression of Txnrd2 in brain and inhibited both the activity of ER stress protein activity and the generation of reactive oxygen species (ROS) by promoting Trx2/Prx3 kilter when administrating sodium selenite in lateral ventricle. This study shed light on the effect of Txnrd2 in regulating oxidative stress and ER stress via Trx2/Prx3 pathway upon ICH and its promising potential as an ICH therapeutic target.


Assuntos
Hemorragia Cerebral , Estresse do Retículo Endoplasmático , Estresse Oxidativo , Ratos Sprague-Dawley , Tiorredoxina Redutase 2 , Tiorredoxinas , Animais , Masculino , Ratos , Astrócitos/metabolismo , Astrócitos/efeitos dos fármacos , Encéfalo/metabolismo , Encéfalo/efeitos dos fármacos , Encéfalo/patologia , Lesões Encefálicas/metabolismo , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/patologia , Modelos Animais de Doenças , Estresse do Retículo Endoplasmático/fisiologia , Estresse do Retículo Endoplasmático/efeitos dos fármacos , Neurônios/metabolismo , Neurônios/efeitos dos fármacos , Neurônios/patologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/fisiologia , Peroxirredoxina III/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Selênio/farmacologia , Transdução de Sinais/fisiologia , Transdução de Sinais/efeitos dos fármacos , Tiorredoxina Redutase 2/metabolismo , Tiorredoxinas/metabolismo
20.
Autophagy ; : 1-20, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38836496

RESUMO

Abnormal expression of long non-coding RNAs (lncRNAs) is associated with the dysfunctions of human trophoblast cells and the occurrence of miscarriage (abnormal early embryo loss). BBC3/PUMA (BCL2 binding component 3) plays significant roles in regulation of cell apoptosis. However, whether specific lncRNAs might regulate BBC3 in trophoblast cells and further induce apoptosis and miscarriage remains completely unclear. Through screening, we identified a novel lnc-HZ12, which was significantly highly expressed in villous tissues of recurrent miscarriage (RM) patients relative to their healthy control (HC) group. Lnc-HZ12 suppressed chaperone-mediated autophagy (CMA) degradation of BBC3, promoted trophoblast cell apoptosis, and was associated with miscarriage. In mechanism, lnc-HZ12 downregulated the expression levels of chaperone molecules HSPA8 and LAMP2A in trophoblast cells. Meanwhile, lnc-HZ12 (mainly lnc-HZ12-SO2 region in F2 fragment) and HSPA8 competitively bound with the 169RVLYNL174 patch on BBC3, which prevented BBC3 from interactions with HSPA8 and impaired the formation of BBC3-HSPA8-LAMP2A complex for CMA degradation of BBC3. Thus, lnc-HZ12 upregulated the BBC3-CASP9-CASP3 pathway and induced trophoblast cell apoptosis. In villous tissues, lnc-HZ12 was highly expressed, CMA degradation of BBC3 was suppressed, and the apoptosis levels were higher in RM vs HC villous tissues, all of which were associated with miscarriage. Interestingly, knockdown of murine Bbc3 could efficiently suppress placental apoptosis and alleviate miscarriage in a mouse miscarriage model. Taken together, our results indicated that lnc-HZ12 and BBC3 played important roles in trophoblast cell apoptosis and miscarriage and might act as attractive targets for miscarriage treatment.Abbreviation: 7-AAD: 7-aminoactinomycin D; BaP: benzopyrene; BBC3/PUMA: BCL2 binding component 3; ChIP: chromatin immunoprecipitation; CHX: cycloheximide; CMA: chaperone-mediated autophagy; CQ: chloroquine; DMSO: dimethyl sulfoxide; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; HC: healthy control; HSPA8: heat shock protein family A (Hsp70) member 8; IP: immunoprecipitation; LAMP2A: lysosomal associated membrane protein 2; LncRNA: long non-coding RNA; mRNA: messenger RNA; MT: mutant-type; NC: negative control; NSO: nonspecific oligonucleotide; PARP1: poly(ADP-ribose) polymerase 1; RIP: RNA immunoprecipitation; RM: recurrent miscarriage; TBP: TATA-box binding protein; WT: wild-type.

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