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1.
Proc Natl Acad Sci U S A ; 121(5): e2304020121, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38261619

RESUMO

Follicular regulatory T cells (Tfr) can play opposite roles in the regulation of germinal center (GC) responses. Depending on the studies, Tfr suppress or support GC and B cell affinity maturation. However, which factors determine positive vs. negative effects of Tfr on the GC B cell is unclear. In this study, we show that GC centrocytes that express MYC up-regulate expression of CCL3 chemokine that is needed for both the positive and negative regulation of GC B cells by Tfr. B cell-intrinsic expression of CCL3 contributes to Tfr-dependent positive selection of foreign Ag-specific GC B cells. At the same time, expression of CCL3 is critical for direct Tfr-mediated suppression of GC B cells that acquire cognate to Tfr nuclear proteins. Our study suggests that CCR5 and CCR1 receptors promote Tfr migration to CCL3 and highlights Ccr5 expression on the Tfr subset that expresses Il10. Based on our findings and previous studies, we suggest a model of chemotactically targeted checkpoint control of B cells undergoing positive selection in GCs by Tfr, where Tfr directly probe and license foreign antigen-specific B cells to complete their positive selection in GCs but, at the same time, suppress GC B cells that present self-antigens cognate to Tfr.


Assuntos
Linfócitos B , Linfócitos T Reguladores , Centro Germinativo , Autoantígenos , Quimiocina CCL3
2.
Am J Physiol Lung Cell Mol Physiol ; 326(1): L39-L51, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37933452

RESUMO

Idiopathic pulmonary fibrosis (IPF) is marked by unremitting matrix deposition and architectural distortion. Multiple profibrotic pathways contribute to the persistent activation of mesenchymal cells (MCs) in fibrosis, highlighting the need to identify and target common signaling pathways. The transcription factor nuclear factor of activated T cells 1 (NFAT1) lies downstream of second messenger calcium signaling and has been recently shown to regulate key profibrotic mediator autotaxin (ATX) in lung MCs. Herein, we investigate the role of NFAT1 in regulating fibroproliferative responses during the development of lung fibrosis. Nfat1-/--deficient mice subjected to bleomycin injury demonstrated improved survival and protection from lung fibrosis and collagen deposition as compared with bleomycin-injured wild-type (WT) mice. Chimera mice, generated by reconstituting bone marrow cells from WT or Nfat1-/- mice into irradiated WT mice (WT→WT and Nfat1-/-→WT), demonstrated no difference in bleomycin-induced fibrosis, suggesting immune influx-independent fibroprotection in Nfat1-/- mice. Examination of lung tissue and flow sorted lineageneg/platelet-derived growth factor receptor alpha (PDGFRα)pos MCs demonstrated decreased MC numbers, proliferation [↓ cyclin D1 and 5-ethynyl-2'-deoxyuridine (EdU) incorporation], myofibroblast differentiation [↓ α-smooth muscle actin (α-SMA)], and survival (↓ Birc5) in Nfat1-/- mice. Nfat1 deficiency abrogated ATX expression in response to bleomycin in vivo and MCs derived from Nfat1-/- mice demonstrated decreased ATX expression and migration in vitro. Human IPF MCs demonstrated constitutive NFAT1 activation, and regulation of ATX in these cells by NFAT1 was confirmed using pharmacological and genetic inhibition. Our findings identify NFAT1 as a critical mediator of profibrotic processes, contributing to dysregulated lung remodeling and suggest its targeting in MCs as a potential therapeutic strategy in IPF.NEW & NOTEWORTHY Idiopathic pulmonary fibrosis (IPF) is a fatal disease with hallmarks of fibroblastic foci and exuberant matrix deposition, unknown etiology, and ineffective therapies. Several profibrotic/proinflammatory pathways are implicated in accelerating tissue remodeling toward a honeycombed end-stage disease. NFAT1 is a transcriptional factor activated in IPF tissues. Nfat1-deficient mice subjected to chronic injury are protected against fibrosis independent of immune influxes, with suppression of profibrotic mesenchymal phenotypes including proliferation, differentiation, resistance to apoptosis, and autotaxin-related migration.


Assuntos
Fibrose Pulmonar Idiopática , Pulmão , Animais , Humanos , Camundongos , Bleomicina/farmacologia , Diferenciação Celular/genética , Fibroblastos/metabolismo , Fibrose Pulmonar Idiopática/induzido quimicamente , Fibrose Pulmonar Idiopática/genética , Fibrose Pulmonar Idiopática/metabolismo , Pulmão/metabolismo , Camundongos Endogâmicos C57BL , Transdução de Sinais
3.
Artigo em Inglês | MEDLINE | ID: mdl-38728170

RESUMO

PURPOSE: This study was the first to evaluate the effect of CYP3A5*3 gene polymorphisms on plasma concentration of perampanel (PER) in Chinese pediatric patients with epilepsy. METHODS: We enrolled 98 patients for this investigation. Plasma PER concentrations were measured using liquid chromatography-tandem mass spectrometry. Leftover samples from standard therapeutic drug monitoring were allocated for genotyping analysis. The primary measure of efficacy was the rate of seizure reduction with PER treatment at the final checkup. RESULTS: The plasma concentration showed a linear correlation with the daily dose taken ( r  = 0.17; P  < 0.05). The ineffective group showed a significantly lower plasma concentration of PER (490.5 ±â€…297.1 vs. 633.8 ±â€…305.5 µg/ml; P  = 0.019). For the mean concentration-to-dose (C/D) ratio, the ineffective group showed a significantly lower C/D ratio of PER (3.2 ±â€…1.7 vs. 3.8 ±â€…2.0; P  = 0.040). The CYP3A5*3 CC genotype exhibited the highest average plasma concentration of PER at 562.8 ±â€…293.9 ng/ml, in contrast to the CT and TT genotypes at 421.1 ±â€…165.6 ng/ml and 260.0 ±â€…36.1 ng/ml. The mean plasma PER concentration was significantly higher in the adverse events group (540.8 ±â€…285.6 vs. 433.0 ±â€…227.2 ng/ml; P  = 0.042). CONCLUSION: The CYP3A5*3 gene's genetic polymorphisms influence plasma concentrations of PER in Chinese pediatric patients with epilepsy. Given that both efficacy and potential toxicity are closely tied to plasma PER levels, the CYP3A5*3 genetic genotype should be factored in when prescribing PER to patients with epilepsy.

4.
Artigo em Inglês | MEDLINE | ID: mdl-38822993

RESUMO

Cysteine (Cys) plays an indispensable role as an antioxidant in the maintenance of bioredox homeostasis. We have constructed an efficient fluorescent probe Mito-Cys based on the binding of indole and naphthol. The acrylic ester group serves as a recognition switch for specific detection of Cys, which undergoes Michael addition and intramolecular cyclization reactions, thereby ensuring the chemical kinetics priority of Cys compared to other biothiols. The probe has good water solubility, large Stokes shift (137 nm), with a detection limit of 21.81 nM. In addition, cell imaging experiments have shown that the probe has excellent mitochondrial targeting ability (R = 0.902). The probe can distinguish between Cys, homocysteine (Hcy) and glutathione (GSH), and can detect Cys specifically and quickly (100 s) to ensure accurate quantitative analysis of Cys changes in cells. More importantly, the probe confirms that ferroptosis inducing factors trigger thiol starvation in mitochondria, which helps to gain a deeper understanding of the physiological and pathological functions related to Cys and ferroptosis.

5.
J Adv Nurs ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38523560

RESUMO

AIMS: To explore the co-occurrence of urinary incontinence and frailty by testing the roles of depression and activity engagement guided by the mechanisms of common cause and interaction pathways. DESIGN: A secondary analysis of a 1-year three-wave panel data collected from older nursing home residents in China. METHODS: Changes in depression and activity engagement were regressed on urinary incontinence and frailty incidence underpinned by the common cause mechanism of chronic conditions co-occurrence, and these changes were also taken as mediators linking from frailty to urinary incontinence incidence supported by the interaction pathways' mechanism. RESULTS: A total of 348 older adults were included in this study, and 55.7% were women. The co-occurrence of urinary incontinence and frailty was found in 16.7% of the participants at baseline. Older adults with sole frailty at baseline had almost twice the rate of incident urinary incontinence (32.7%) compared with those without (16.7%) over a 1-year period. The subsample analyses showed that changes in depression and activity engagement failed to significantly predict the incidence of urinary incontinence and frailty. The mediating roles of these changes linking frailty to urinary incontinence incidence were also not statistically significant. CONCLUSION: The co-occurrence of urinary incontinence and frailty is prevalent in older nursing home residents. Older adults with frailty at baseline are more likely to develop urinary incontinence a year later. The common cause and interaction pathways mechanisms for the co-occurrence of urinary incontinence and frailty were not verified with changes in depression and activity engagement. IMPLICATIONS FOR THE PROFESSION AND/OR PATIENT CARE: The phenomenon of urinary incontinence and frailty co-occurrence should be given extreme emphasis. Although statistically significant findings on the roles of depression and activity engagement were not inferred, this study provides multiple possibilities for future studies to test and depict a clear picture of this co-occurrence. IMPACT: What problem did the study address? This study was designed to test the roles of depression and activity engagement in predicting the incidence of urinary incontinence and frailty, and the mediating roles in linking frailty to urinary incontinence incidence. What were the main findings? Despite the methodological pitfalls in literature have been addressed, neither depression nor activity engagement would significantly predict the incidence of urinary incontinence and frailty in older adults. Their mediating roles in linking frailty to urinary incontinence incidence were also not significant. Where and on whom will the research have an impact? Our findings add important pieces of evidence to promote researchers' understanding and provide an important basis for untangling the puzzle of urinary incontinence and frailty co-occurrence. REPORTING METHOD: The report of this study followed the Strengthening the Reporting of Observational Studies in Epidemiology (STROBE) statement guidelines. PATIENT OR PUBLIC CONTRIBUTION: No patient or public contribution.

6.
J Org Chem ; 88(19): 13838-13846, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37750715

RESUMO

An effective (NHC)AgCl catalysis was developed in the hydroborylation of cyclopropenes with B2pin2, delivering a variety of cyclopylboronates in a stereoselective manner, which could be easily transformed for the construction of versatile cyclopropanes. This protocol works effectively under mild reaction conditions in an open-air atmosphere, and it was easy to apply on a gram scale. This novel method in detail was also explored by control experiments, providing a number of key insights. The kinetic process followed by 1H NMR indicated that the reaction was finished in 15 min. Furthermore, the mechanism of silver(I)-catalyzed hydroborylation of cyclopropenes was proposed, with the protonation by methanol as the rate-determining step.

7.
Org Biomol Chem ; 21(48): 9534-9541, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38009332

RESUMO

Hydroarylation of alkenes is one of the most straightforward and atom-economical strategy for the construction of multi-aryl-substituted alkanes, but systematic studies have been limited to transition metal catalysis. Here we report a hexafluoroisopropanol (HFIP)-promoted hydroarylation of alkenes with indoles without the presence of transition metal catalysts or any additive. HFIP was the only reagent used in this work, and could be easily removed via evaporation, and recovered via distillation in industry settings. This reaction was shown to provide an efficient, clean and operationally simple procedure with a remarkable substrate scope and versatile transformations, delivering a variety of multi-aryl alkanes incorporating the indole motif. In preliminary studies, several of these products showed biologically activity against cells from an array of human cancer cell lines. A mechanistic study was also carried out and suggested that the quinone methide might be the key intermediate. And in contrast to the conclusions of a previous report, the current work suggested that protonation by HFIP might not be the rate-determining step.

8.
Appl Opt ; 62(24): 6507-6517, 2023 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-37706845

RESUMO

We propose an ultra-wide angle panoramic imaging system based on a multiplexed reflective surface, which consists of a panoramic head unit (PHU) and the relay lens group. The multiplexed reflective surface is applied in the PHU to reflect light from glass and air for imaging, obtaining the front and rear view channels, respectively. With a field of view (FoV) of 360∘×(35∘-120∘) and an f-number of four, this system has good image quality and relative illumination in the FoV. In addition, it has loose tolerance requirements and a diameter ratio of 7.2, reducing the difficulty of manufacturing and assembly. This optical system architecture provides a promising solution for panoramic perception over a wider FoV.

9.
BMC Anesthesiol ; 22(1): 94, 2022 04 04.
Artigo em Inglês | MEDLINE | ID: mdl-35379189

RESUMO

BACKGROUND: Deep neuromuscular blockade may be beneficial on surgical space conditions during laparoscopic surgery. The effects of moderate neuromuscular blockade combined with transverse abdominal plane block (TAPB) on surgical space conditions during laparoscopic surgery have not been described. This work investigated whether the above combination is associated with similar surgical space conditions to those of deep neuromuscular blockade. METHODS: Eighty patients undergoing elective laparoscopic surgery for colorectal cancer were randomly divided into two groups. The intervention group was treated with moderate neuromuscular blockade (train-of-four (TOF) count between 1 and 3) combined with TAPB (M group), while the control group was treated with deep neuromuscular blockade (D group), with a TOF count of 0 and a post-tetanic count (PTC) ≥1. Both groups received the same anesthesia management. The distance between the sacral promontory and the umbilical skin during the operation was compared between the two groups. The surgeon scored the surgical space conditions according to a five-point ordinal scale. Patients' pain scores were evaluated 8 h after the operation. RESULTS: The distance from the sacral promontory to the umbilical skin after pneumoperitoneum was similar between the D group and M group (16.03 ± 2.17 cm versus 16.37 ± 2.78 cm; P = 0.544). The 95% confidence intervals of the difference in the distance from the sacral promontory to the umbilical skin between the two groups were - 1.45-0.77 cm. According to the preset non-inferior standard of 1.5 cm, (- 1.45, ∞) completely fell within (- 1.50, ∞), and the non-inferior effect test was qualified. No significant difference was found in the surgical rating score between the two groups. The dosage of rocuronium in the group D was significantly higher than that in the group M (P < 0.01). The M group had significantly lower pain scores than the D group 8 h after the operation (P < 0.05). CONCLUSIONS: Moderate neuromuscular blockade combined with TAPB applied to laparoscopic colorectal cancer surgery can provide surgical space conditions similar to those of deep neuromuscular blockade. In addition, it reduces the use of muscle relaxants, relieves postoperative pain within 4 h after operation, and shorten the extubation time and stay in PACU when neostigmine was used as muscle relaxant antagonist. TRIAL REGISTRATION: chictr.org.cn ( ChiCTR2000034621 ), registered on July 12, 2020.


Assuntos
Cirurgia Colorretal , Laparoscopia , Bloqueio Neuromuscular , Músculos Abdominais , Humanos , Rocurônio
10.
Allergy Asthma Proc ; 43(3): 209-219, 2022 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-35524352

RESUMO

Background: Cough is often the most prominent and intractable symptom reported by patients with asthma, but few studies have explored the characteristics of patients with asthma and with chronic cough (CC) in a real-world setting. Methods: In a prospective cohort study, patients ages ≥ 18 years with stable asthma were consecutively recruited at the West China Hospital, Sichuan University. The patients were classified as having asthma with CC (the CC group) or asthma with non-CC (the non-CC group) after 3 months of optimized asthma therapy according to standard guidelines. Multidimensional assessment was performed at baseline, followed by a 12-month follow-up to assess asthma exacerbations. Results: Of 323 patients with asthma, 127 patients were assigned to the CC group and 196 patients were assigned to the non-CC group. The participants with CC were older and had more airflow obstruction; worse asthma control and quality of life; increased airway inflammation; upper respiratory tract infection as a trigger; and more comorbidities, such as psychological dysfunction, rhinitis, chronic obstructive pulmonary disease, and bronchiectasis. They reported greater work productivity loss and daily activity impairment, and increased moderate-to-severe exacerbations. Conclusion: The participants with asthma and with CC had a significant disease burden, with increased exacerbations, health-care utilization, and impaired work productivity and daily activity. These observations indicated potential clinical implications in patients with asthma and with CC, and call for more attention to this aspect of asthma.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Adolescente , Asma/complicações , Asma/diagnóstico , Asma/epidemiologia , Doença Crônica , Tosse/diagnóstico , Tosse/epidemiologia , Humanos , Inflamação/complicações , Inflamação/epidemiologia , Pulmão , Estudos Prospectivos , Qualidade de Vida
11.
J Adv Nurs ; 78(4): 991-1000, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34423462

RESUMO

AIM: To explore the status of quality of life and psychological capital and analyse the different effects of psychological capital on the quality of life of cancer patients with different preferences for nurse spiritual therapeutics. DESIGN: A cross-sectional survey was used. METHODS: Two hundred and eight cancer patients were recruited using convenience sampling from a tertiary Chinese hospital, between March and July 2019. Data on preferences for nurse spiritual therapeutics (PNST), psychological capital (PsyCap) and quality of life (QoL) were collected using paper questionnaires. Hierarchical multiple regression was employed to investigate the different influences of PsyCap on QoL of cancer patients with various levels of PNST. RESULTS: Compared with patients having high PNST, patients with mild-moderate PNST experienced lower self-efficacy, hope, optimism, PsyCap and social/family well-being. PsyCap significantly explained the variance on QoL of patients with various levels of PNST. Age, gender, presence of caregiver were significant factors influencing physical, social/family and emotional well-being of patients with high PNST. CONCLUSION: The present study demonstrates disparities in PsyCap and QoL between cancer patients with mild-moderate and high PNST. It is essential to be aware of the positive influences of PsyCap on QoL and develop effective interventions for patients to improve their QoL, especially for those with mild-moderate PNST. IMPACT: It is necessary to realize the benefits of PsyCap on QoL of cancer patients with various levels of PNST. Appropriate training for nurses needs to be developed to promote their spiritual care competencies. Moreover, supportive interventions should be developed for cancer patients to improve their PsyCap and QoL.


Assuntos
Neoplasias , Preferência do Paciente , Qualidade de Vida , Terapias Espirituais , Estudos Transversais , Humanos , Neoplasias/psicologia , Neoplasias/terapia , Otimismo , Preferência do Paciente/estatística & dados numéricos , Qualidade de Vida/psicologia , Autoeficácia , Terapias Espirituais/enfermagem , Inquéritos e Questionários
12.
J Nurs Manag ; 30(5): 1273-1282, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35338533

RESUMO

AIM: To investigate the associations between perceived overqualification, organisational commitment and work passion of nurses. BACKGROUND: Few studies have considered the effects of perceived overqualification and organisational commitment on work passion of nurses, especially in developing countries. METHODS: This is a multicentre cross-sectional study. A total of 4511 nurses from eight tertiary hospitals were recruited. The Scale of Perceived OverQalification (SPOQ), the Organizational Commitment Scale (OCS) and the Work Passion Scale (WPS) were used to collect the data. Hierarchical multiple regression were employed. RESULTS: Perceived overqualification and organisational commitment were the main predictors for both harmonious and obsessive passions (each p < .001). The unique effect of organisational commitment (ßharmonious  = .608, ßobsessive  = .556) on work passion were six to eight times larger than these of perceived overqualification (ßharmonious = -.079, ßobsessive = .085). CONCLUSION: Our findings indicate that high perceived overqualification clearly reduces nurses' harmonious passion and increases their obsessive passion, whereas high organisational commitment significantly promotes nurses' harmonious and obsessive passions. IMPLICATIONS FOR NURSING MANAGEMENT: Nurse managers should distinguish the different effects of perceived overqualification and organisational commitment on work passion. Effective intervention should be developed to release nurses' potential abilities and improve their organisational commitment and work passion. Chinese Clinical Trial Registry: ChiCTR2100047974.


Assuntos
Enfermeiros Administradores , Enfermeiras e Enfermeiros , Recursos Humanos de Enfermagem Hospitalar , Estudos Transversais , Emoções , Humanos , Satisfação no Emprego , Cultura Organizacional , Inquéritos e Questionários
13.
Org Biomol Chem ; 19(29): 6417-6421, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34236072

RESUMO

A thorough study of mild and environmentally friendly electrochemical-induced hydroxylation of aryl halides without a catalyst is presented. The best protocol consists of hydroxylation of different aryl iodides and aryl bromides by water solution in the presence of Et3N under air, affording the target phenols in good isolated yields. Moreover, aryl chlorides were successfully employed as substrates. This methodology also provides a direct pathway for the formation of deoxyphomalone, which displayed a significant anti-proliferation effect.

14.
Org Biomol Chem ; 19(5): 998-1003, 2021 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-33448270

RESUMO

An efficient and practical electrochemically catalyzed transition metal-free process for the synthesis of substituted quinazolinones from simple and readily available o-aminobenzonitriles and aldehydes in water has been accomplished. I2/base and water play an unprecedented and vital role in the reaction. By electrochemically catalysed hydrolysis of o-aminobenzonitriles, the synthesis of quinazolinones with benzaldehyde was first proposed. The synthetic utility of this method was demonstrated by gram-scale operation, as well as the preparation of bioactive N-(2,5-dichlorophenyl)-6-(2,2,2-trifluoroethoxy) pteridin-4-amine, which enables straightforward, practical and environmentally benign quinazolinone formation.

15.
Exp Lung Res ; 47(2): 78-86, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33238771

RESUMO

PURPOSE: The regulation effect and mechanism of respiratory syncytial virus (RSV) infection on the expression of tachykinin substance P (SP) in airway epithelial cells was investigated. METHODS: The regulation of SP expression by RSV was investigated in the BEAS-2B airway epithelial cell line. RT-qPCR, immunofluorescence, and ELISA assay were used to examine the expression of the SP encoding gene TAC1, the intracellular SP protein expression, and the extracellular SP secretion. RESULTS: The mRNA expression of TAC1 and the intracellular SP protein level in BEAS-2B cells were significantly enhanced by RSV infection with multiplicity of infection (MOI) values of both 1 and 0.1 at 48 hours post infection. Heat-inactivated and UV-inactivated RSV, but not live RSV, significantly induced SP secretion in both control BEAS-2B cells and CX3CR1 receptor knockout cells without affecting the TAC1 gene expression or cell viability. RSV G protein (2-10 µg/ml) and fractalkine (10-50 ng/ml), both CX3CR1 receptor ligands, did not affect SP secretion in BEAS-2B cells. Inhibition of STAT1 phosphorylation by fludarabine (1 µM) markedly reduced the RSV-induced TAC1 gene expression and antagonized the inhibition of RSV replication by interferon-α in BEAS-2B cells. CONCLUSIONS: STAT1 participates in RSV infection-induced SP expression in airway epithelial cells.


Assuntos
Células Epiteliais/virologia , Infecções por Vírus Respiratório Sincicial , Vírus Sincicial Respiratório Humano , Fator de Transcrição STAT1 , Humanos , Sistema Respiratório , Substância P
16.
J Pineal Res ; 69(2): e12665, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32358852

RESUMO

Death-associated protein kinase 1 (DAPK1) is upregulated in the brains of human Alzheimer's disease (AD) patients compared with normal subjects, and aberrant DAPK1 regulation is implicated in the development of AD. However, little is known about whether and how DAPK1 function is regulated in AD. Here, we identified melatonin as a critical regulator of DAPK1 levels and function. Melatonin significantly decreases DAPK1 expression in a post-transcriptional manner in neuronal cell lines and mouse primary cortical neurons. Moreover, melatonin directly binds to DAPK1 and promotes its ubiquitination, resulting in increased DAPK1 protein degradation through a proteasome-dependent pathway. Furthermore, in tau-overexpressing mouse brain slices, melatonin treatment and the inhibition of DAPK1 kinase activity synergistically decrease tau phosphorylation at multiple sites related to AD. In addition, melatonin and DAPK1 inhibitor dramatically accelerate neurite outgrowth and increase the assembly of microtubules. Mechanistically, melatonin-mediated DAPK1 degradation increases the activity of Pin1, a prolyl isomerase known to play a protective role against tau hyperphosphorylation and tau-related pathologies. Finally, elevated DAPK1 expression shows a strong correlation with the decrease in melatonin levels in human AD brains. Combined, these results suggest that DAPK1 regulation by melatonin is a novel mechanism that controls tau phosphorylation and function and offers new therapeutic options for treating human AD.


Assuntos
Doença de Alzheimer/enzimologia , Encéfalo/enzimologia , Proteínas Quinases Associadas com Morte Celular/biossíntese , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Melatonina/farmacologia , Doença de Alzheimer/patologia , Animais , Encéfalo/patologia , Células HeLa , Humanos , Melatonina/metabolismo , Camundongos
17.
Angew Chem Int Ed Engl ; 58(3): 897-901, 2019 01 14.
Artigo em Inglês | MEDLINE | ID: mdl-30456924

RESUMO

A palladium-catalyzed enantioselective sequential ring-opening/cross-coupling of cyclobutanones is disclosed that provides chiral indanones bearing C3-quaternary stereocenters. The reaction process involves palladium-catalyzed nucleophilic addition of cyclobutanones and aryl halides, enantioselective ß-carbon elimination, and intermolecular trapping of a transient σ-alkylpalladium complex with boronic acids. Alternatively, an intramolecular cyclopropanation is realized through C-H bond functionalization in the absence of external coupling reagents, affording chiral cyclopropane-fused-indanones in good yields and enantioselectivity.

18.
Org Biomol Chem ; 16(43): 8090-8094, 2018 11 07.
Artigo em Inglês | MEDLINE | ID: mdl-30328461

RESUMO

An efficient copper-catalyzed three-component reaction of 2-haloaniline, ammonia and aldehyde for the synthesis of benzimidazoles with 1,10-phenanthroline as the ligand has been developed. A variety of substituted benzimidazole derivatives can be obtained in yields up to 95%.

19.
Biochem Biophys Res Commun ; 490(1): 62-68, 2017 08 12.
Artigo em Inglês | MEDLINE | ID: mdl-28600172

RESUMO

MicroRNA-31 (miR-31) is an evolutionarily conserved microRNA, and its biological function in colorectal cancer and other cancers is controversial. In this study, we identified the host gene of mouse miR-31 and found that miR-31 was over-expressed in both human colorectal cancer and mouse colon cancer models. We here developed a miR-31 conditional knockout mouse model that allows for colon epithelium specific deletion of miR-31 to investigate its functionality in colon cancer development. We demonstrated that mice with miR-31 conditional deletion resulted in more severe colitis-associated cancer than wild-type, and we further identified Wdr5 as an important target of miR-31.


Assuntos
Colite/complicações , Colite/genética , Neoplasias Colorretais/etiologia , Neoplasias Colorretais/genética , MicroRNAs/genética , Animais , Colite/patologia , Neoplasias Colorretais/patologia , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Regulação para Cima/genética
20.
J Immunol ; 194(9): 4185-98, 2015 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-25825452

RESUMO

Psoriasis is a chronic recurrent inflammatory skin disorder characterized by the dysregulated cross-talk between epidermal keratinocytes and immune cells, leading to keratinocyte hyperproliferation. Several studies demonstrated that Wnt pathway genes were differentially expressed in psoriatic plaques and likely were involved in the pathophysiology of disease. However, the molecular mechanisms underlying Wnt signaling regulation in epidermal hyperplasia in psoriasis remain largely unknown. We report that the expression of secreted frizzled-related protein (SFRP) 4, a negative regulator of the Wnt signaling pathway, was diminished in lesional skin of mouse models and patients with psoriasis. SFRP4 directly inhibited excessive keratinocyte proliferation evoked by proinflammatory cytokines in vitro. Pharmacological inhibition of Wnt signaling or intradermal injection of SFRP4 decreased the severity of the psoriasiform skin phenotype in vivo, including decreased acanthosis and reduced leukocyte infiltration. Mechanistically, we identified that aberrant promoter methylation resulted in epigenetic downregulation of SFRP4 in inflamed skin of patients with psoriasis and in the IL-23-induced mouse model. Our findings suggest that this epigenetic event is critically involved in the pathogenesis of psoriasis, and the downregulation of SFRP4 by CpG island methylation is one possible mechanism contributing to the hyperplasia of epidermis in the disease.


Assuntos
Regulação para Baixo/genética , Epiderme/patologia , Epigênese Genética/genética , Hiperplasia/genética , Proteínas Proto-Oncogênicas/genética , Psoríase/genética , Adulto , Animais , Metilação de DNA , Feminino , Humanos , Hiperplasia/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Regiões Promotoras Genéticas/genética , Psoríase/patologia , Via de Sinalização Wnt
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