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1.
Neural Regen Res ; 20(1): 29-40, 2025 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38767474

RESUMO

The development of neurodegenerative diseases is closely related to the disruption of central nervous system homeostasis. Microglia, as innate immune cells, play important roles in the maintenance of central nervous system homeostasis, injury response, and neurodegenerative diseases. Lactate has been considered a metabolic waste product, but recent studies are revealing ever more of the physiological functions of lactate. Lactylation is an important pathway in lactate function and is involved in glycolysis-related functions, macrophage polarization, neuromodulation, and angiogenesis and has also been implicated in the development of various diseases. This review provides an overview of the lactate metabolic and homeostatic regulatory processes involved in microglia lactylation, histone versus non-histone lactylation, and therapeutic approaches targeting lactate. Finally, we summarize the current research on microglia lactylation in central nervous system diseases. A deeper understanding of the metabolic regulatory mechanisms of microglia lactylation will provide more options for the treatment of central nervous system diseases.

2.
Artigo em Inglês | MEDLINE | ID: mdl-38935995

RESUMO

Salinity acclimatization refers to the physiological and behavioral adjustments made by crustaceans to adapt to varying salinity environments. The eyestalk, a neuroendocrine organ in crustaceans, plays a crucial role in salinity acclimatization. To elucidate the molecular mechanisms underlying eyestalk involvement in mud crab (Scylla paramamosain) acclimatization, we employed RNA-seq technology to analyze transcriptomic changes in the eyestalk under low (5 ppt) and standard (23 ppt) salinity conditions. This analysis revealed 5431 differentially expressed genes (DEGs), with 2372 upregulated and 3059 downregulated. Notably, these DEGs were enriched in crucial biological pathways like metabolism, osmoregulation, and signal transduction. To validate the RNA-seq data, we further analyzed 15 DEGs of interest using qRT-PCR. Our results suggest a multifaceted role for the eyestalk: maintaining energy homeostasis, regulating hormone synthesis and release, PKA activity, and downstream signaling, and ensuring proper ion and osmotic balance. Furthermore, our findings indicate that the crustacean hyperglycemic hormone (CHH) may function as a key regulator, modulating carbonic anhydrase expression through the activation of the PKA signaling pathway, thereby influencing cellular osmoregulation, and associated metabolic processes. Overall, our study provides valuable insights into unraveling the molecular mechanisms of mud crab acclimatization to low salinity environments.

3.
Heliyon ; 10(3): e25556, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38356600

RESUMO

As an important marine aquaculture species, the mud crab (Scylla paramamosain) is a good candidate for studying the osmoregulatory mechanism of crustaceans. While previous studies have focused on the osmoregulatory function of the gills, this study aims to explore the osmoregulatory function of the antennal glands. By the comparative transcriptomic analysis, we found the pathways of ion regulation including "proximal tubule bicarbonate reclamation" and "mineral absorption" were activated in the antennal glands of the crabs long-term dwelling in low salinity. The enhanced ionic reabsorption was associated with up-regulated ion transport genes such as NKA, CA-c, VPA, and NHE, and with energy metabolism genes such as MDH, SLC25, and PEPCK. The upregulation of NKA and CA-c was also verified by the increased enzyme activity. The lowered osmolality and ion concentration of the hemolymph and the enlarged labyrinth lumen and hemolymph capillary inside the antennal glands indicated the infiltration of external water and the responsively increase of urine excretion, which explained the requirement of enhanced ionic reabsorption. To further confirm these findings, we examined the change of gene expression, enzyme activity, internal ion concentration, and external ion concentration during a 96 h low salinity challenge with seven intervals. The results were basically consistent with the results as shown in the long-term low salinity adaptation. The present study provides valuable information on the osmoregulatory function of the antennal glands of S. paramamosain. The implication of this study in marine aquaculture is that it provides valuable information on the osmoregulatory mechanism of mud crabs, which can be used to improve their culture conditions and enhance their tolerance to salinity stress. The identified genes and pathways involved in osmoregulation can also be potential targets for genetic selection and breeding programs to develop more resilient mud crab strains for aquaculture.

4.
Nurs Ethics ; : 9697330231221218, 2024 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-38369759

RESUMO

BACKGROUND: The urgency of ensuring adequate moral courage in clinical nursing practice is evident. However, currently, there are few formal intervention plans targeted at enhancing the moral courage of nurses. AIM: To develop a training program for improving the moral courage of nurses using the modified Delphi method. RESEARCH DESIGN: A modified Delphi study. PARTICIPANTS AND RESEARCH CONTEXT: From November to December 2022, a literature review and expert group discussion were conducted to develop a preliminary training plan framework. From January to March 2023, a two-round Delphi survey was performed, and a consensus was reached regarding the plan through online questionnaires. Descriptive statistics were used to analyze the data. ETHICAL CONSIDERATIONS: This study was approved by the institutional ethics committee (No. 138, 30 August 2021). All participants provided written informed consent. RESULTS: Consensus was reached on eight themes and 33 items to strengthen the moral courage training program for nurses. CONCLUSIONS: Guided by a unified goal of moral education, a multi-level and acceptable intervention plan was designed to enhance the moral courage of nurses.

5.
Artigo em Inglês | MEDLINE | ID: mdl-38070330

RESUMO

In the present study, BGISEQ-500 RNA-Seq technology was adopted to investigate how Scylla paramamosain adapts to salinity tolerance at the molecular level and explores changes in gene expression linked to salinity adaptation following exposure to both low salinity (5 ‰) and standard salinity (23 ‰) conditions. A total of 1100 and 520 differentially expressed genes (DEGs) were identified in the anterior and posterior gills, respectively, and their corresponding expression patterns were visualized in volcano plots and a heatmap. Further analysis highlighted significant enrichment of well-established gene functional categories and signaling pathways, including those what associated with cellular stress response, ion transport, energy metabolism, amino acid metabolism, H2O transport, and physiological stress compensation. We also selected key DEGs within the anterior and posterior gills that encode pivotal stress adaptation and tolerance modulators, including AQP, ABCA1, HSP 10, A35, CAg, NKA, VPA, CAc, and SPS. Interestingly, A35 in the gills might regulate osmolality by binding CHH in response to low salinity stress or serve as a mechanism for energy compensation. Taken together, our findings elucidated the intricate molecular mechanism employed by S. paramamosain for salinity adaptation, which involved distinct gene expression patterns in the anterior and posterior gills. These findings provide the foothold for subsequent investigations into salinity-responsive candidate genes and contribute to a deeper understanding of S. paramamosain's adaptation mechanisms in low-salinity surroundings, which is crucial for the development of low-salinity species cultivation and the establishment of a robust culture model.


Assuntos
Braquiúros , Animais , Braquiúros/fisiologia , Salinidade , Brânquias/metabolismo , Perfilação da Expressão Gênica , Expressão Gênica
6.
Artigo em Inglês | MEDLINE | ID: mdl-38122925

RESUMO

Crustacean hyperglycemic hormone (CHH) superfamily peptides constitute a group of neurohormones, including the crustacean hyperglycemic hormone (CHH), molt-inhibiting hormone (MIH), and gonad-inhibiting hormone (GIH) or vitellogenesis-inhibiting hormone (VIH), which reportedly play an essential role in regulating various biological activities by binding to their receptors in crustaceans. Although bioinformatics analyses have identified G protein-coupled receptors (GPCRs) as potential CHH receptors, no validation through binding experiments has been carried out. This study employed a eukaryotic expression system, HEK293T cell transient transfection, and ligand-receptor interaction tests to identify the GPCRs of CHHs in the mud crab Scylla paramamosain. We found that four GPCRs (Sp-GPCR-A34-A37) were activated by their corresponding CHHs (Sp-CHH1-v1, Sp-MIH, Sp-VIH) in a dose-dependent manner. Of these, Sp-GPCR-A34 was exclusively activated by Sp-VIH; Sp-GPCR-A35 was activated by Sp-CHH1-v1 and Sp-VIH, respectively; Sp-GPCR-A36 was activated by Sp-CHH1-v1 and Sp-MIH; Sp-GPCR-A37 was exclusively activated by Sp-MIH. The half-maximal effective concentration (EC50) values for all CHHs/GPCRs pairs (both Ca2+ and cAMP signaling) were in the nanomolar range. Overall, our study provided hitherto undocumented evidence of the presence of G protein-coupled receptors of CHH in crustaceans, providing the foothold for further studies on the signaling pathways of CHHs and their corresponding GPCRs.


Assuntos
Braquiúros , Hormônios de Invertebrado , Humanos , Animais , Braquiúros/metabolismo , Células HEK293 , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Peptídeos/química , Proteínas de Transporte/metabolismo , Hormônios de Invertebrado/genética , Hormônios de Invertebrado/metabolismo , Proteínas de Artrópodes/genética , Proteínas de Artrópodes/metabolismo
7.
Biomed Pharmacother ; 168: 115637, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37844358

RESUMO

COVID-19, caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), emerged as a global health threat in 2019. An important feature of the disease is that multiorgan symptoms of SARS-CoV-2 infection persist after recovery. Evidence indicates that people who recovered from COVID-19, even those under the age of 65 years without cardiovascular risk factors such as smoking, obesity, hypertension, and diabetes, had a significantly increased risk of cardiovascular disease for up to one year after diagnosis. Therefore, it is important to closely monitor individuals who have recovered from COVID-19 for potential cardiovascular damage that may manifest at a later stage. Ferroptosis is an iron-dependent form of non-apoptotic cell death characterized by the production of reactive oxygen species (ROS) and increased lipid peroxide levels. Several studies have demonstrated that ferroptosis plays an important role in cancer, ischemia/reperfusion injury (I/RI), and other cardiovascular diseases. Altered iron metabolism, upregulation of reactive oxygen species, and glutathione peroxidase 4 inactivation are striking features of COVID-19-related cardiovascular injury. SARS-CoV-2 can cause cardiovascular ferroptosis, leading to cardiovascular damage. Understanding the mechanism of ferroptosis in COVID-19-related cardiovascular injuries will contribute to the development of treatment regimens for preventing or reducing COVID-19-related cardiovascular complications. In this article, we go over the pathophysiological underpinnings of SARS-CoV-2-induced acute and chronic cardiovascular injury, the function of ferroptosis, and prospective treatment approaches.


Assuntos
COVID-19 , Doenças Cardiovasculares , Ferroptose , Traumatismo por Reperfusão , Humanos , Idoso , Ferroptose/fisiologia , Espécies Reativas de Oxigênio/metabolismo , COVID-19/complicações , Doenças Cardiovasculares/etiologia , SARS-CoV-2/metabolismo , Ferro/metabolismo
8.
Animals (Basel) ; 13(11)2023 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-37889731

RESUMO

Feminization-1c (Fem-1c) is important for sex differentiation in the model organism Caenorhabditis elegans. In our previous study, the basic molecular characteristics of the Fem-1c gene (EsFem-1c) in Eriocheir sinensis (Henri Milne Edwards, 1854) were cloned to determine the relationship with sex differentiation. In this study, the genomic sequence of EsFem-1c contained five exons and four introns, with an exceptionally long 3'UTR sequence. The qRT-PCR results of EsFem-1c demonstrated lower tissue expression in the androgenic gland of the intersex crab than the normal male crab, implying that EsFem-1c plays a role in crab AG development. RNA interference experiments and morphological observations of juvenile and mature crabs indicated that EsFem-1c influences sexual development in E. sinensis. A dual-luciferase reporter assay disclosed that tcf-miR-315-5p effectively inhibits the translation of the EsFem-1c gene, influencing male development. An intriguing finding was that miRNA tcf-miR-307 could increase EsFem-1c expression by binding to the alternative splicing region with a length of 248 bp (ASR-248) in the 3'UTR sequence. The present research contributes to a better understanding of the molecular regulation mechanism of EsFem-1c and provides a resource for future studies of the miRNA-mediated regulation of sexual development and regulation in E. sinensis.

9.
Drug Des Devel Ther ; 17: 1881-1888, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37384214

RESUMO

Purpose: Ibuprofen is the first of the nonsteroidal anti-inflammatory drug (NSAID) to be used in the clinic. Our aim was to explore the pharmacokinetics (PK), bioequivalence, food effect, and safety of oral ibuprofen sustained-release capsules by two sponsors in healthy volunteers (HVs). Methods: Two separate randomized, open-label, single-dose, crossover-design studies were conducted: a fasting study (n = 24) and a fed study (n = 24). In each study, HVs were 1:1 divided into two groups (T-R and R-T) and received 0.3-g/capsule ibuprofen with a 3-day washout. The plasma was collected for up to 24 hours at the time point after dosing on Day 1/Day 4. The plasma concentrations of ibuprofen were measured using an HPLC-MS/MS method, and PK parameters were determined by noncompartmental methods. Results: Forty-eight healthy volunteers were enrolled. In fasting subjects, the maximum plasma concentration (Cmax, mean ± SD) was 14.86±3.19 µg/mL at 5.0 (4.0, 7.0) hours (median [min, max]) for sponsor T, and 13.88±2.60 µg/mL at 4.5 (3.0, 8.0) hours for sponsor R. In fed subjects, Cmax was 21.31±4.08 µg/mL at 5.6 (4.3, 10.0) hours for sponsor T, and 19.77±3.36 µg/mL at 6.0 (2.0, 8.0) hours for sponsor R. All 90% confidence intervals (CIs) for Cmax, AUC0-t, and AUC0-∞ were within the bioequivalence bounds (80-125%) both fasting and fed studies. Conclusion: Ibuprofen is well tolerated and has a favorable safety profile. In both fasting and fed study, there were no serious AEs, or AEs leading to withdrawal. Bioequivalence is achieved under fasting and fed conditions, supporting the demonstration of biosimilarity.


Assuntos
População do Leste Asiático , Ibuprofeno , Humanos , Equivalência Terapêutica , Ibuprofeno/efeitos adversos , Cápsulas , Preparações de Ação Retardada , Espectrometria de Massas em Tandem
10.
Artigo em Inglês | MEDLINE | ID: mdl-37178607

RESUMO

The antennal glands (AnGs) are recognized as an important organ that functions in ion regulation and excretion in decapods. Previously, many studies had explored this organ at the biochemical, physiological, and ultrastructural levels but had few molecular resources. In this study, the transcriptomes of the male and female AnGs of Portunus trituberculatus were sequenced using RNA sequencing (RNA-Seq) technology. Genes involved in osmoregulation and organic/inorganic solute transport were identified. This suggests that AnGs might be involved in these physiological functions as versatile organs. A total of 469 differentially expressed genes (DEGs) were further identified between male and female transcriptomes and found to be male-biased. Enrichment analysis showed that females were enriched in amino acid metabolism and males were enriched in nucleic acid metabolism. These results suggested differences in possible metabolic patterns between males and females. Furthermore, two transcription factors related to reproduction, namely AF4/FMR2 family members Lilli (Lilli) and Virilizer (Vir), were identified in DEGs. Lilli was found to be specifically expressed in the male AnGs, whereas Vir showed high expression levels in the female AnGs. The expression of up-regulated metabolism and sexual development-related genes in three males and six females was verified by qRT-PCR and the pattern was found to be consistent with the transcriptome expression pattern. Our results suggest that although the AnG is a unified somatic tissue composed of individual cells, it still demonstrates distinct sex-specific expression patterns. These results provide foundational knowledge of the function and differences between male and female AnGs in P. trituberculatus.


Assuntos
Braquiúros , Transcriptoma , Feminino , Masculino , Animais , Braquiúros/genética , Natação , Perfilação da Expressão Gênica , Osmorregulação
11.
JMIR Serious Games ; 11: e42944, 2023 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-37097717

RESUMO

BACKGROUND: Exercise is effective for musculoskeletal pain. However, physical, social, and environmental factors make it difficult for older adults to persist in exercising. Exergaming is a new pathway that combines exercise with gameplay and may be helpful for older adults to overcome these difficulties and engage in regular exercise. OBJECTIVE: This systematic review aimed to determine the efficacy of exergaming to improve musculoskeletal pain in older adults. METHODS: The search was performed in 5 databases (PubMed, Embase, CINAHL, Web of Science, and Cochrane Library). The risk of bias for randomized controlled studies was assessed using the revised Cochrane Risk of Bias tool in randomized trials (RoB 2), and the methodological quality was assessed using the Physiotherapy Evidence-Based Database scale. Standardized mean difference and 95% CI were calculated using fixed-effects model meta-analyses in the Review Manager version 5.3 (RevMan 5.3). RESULTS: Seven randomized controlled studies were included, which contained 264 older adults. Three of the 7 studies reported significant improvements in pain after the exergaming intervention, but only 1 reported a significant difference between groups after adjustment for baseline (P<.05), and another reported a significant improvement in thermal pain between the 2 groups (P<.001). The results of the meta-analysis of the 7 studies showed no statistically significant improvement in pain compared to the control group (standardized mean difference -0.22; 95% CI -0.47 to 0.02; P=.07). CONCLUSIONS: Although the effects of exergames on musculoskeletal pain in older adults are unknown, exergame training is generally safe, fun, and appealing to older adults. Unsupervised exercise at home is feasible and cost-effective. However, most of the current studies have used commercial exergames, and it is recommended that there should be more cooperation between industries in the future to develop professional rehabilitation exergames that are more suitable for older adults. The sample sizes of the studies included are small, the risk of bias is high, and the results should be interpreted with caution. Further randomized controlled studies with large sample sizes, high quality, and rigor are needed in the future. TRIAL REGISTRATION: PROSPERO International Prospective Register of Systematic Reviews CRD42022342325; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=342325.

12.
Chem Commun (Camb) ; 59(39): 5902-5905, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37097750

RESUMO

The chiral phosphoric acid-catalyzed asymmetric intermolecular formal [3+2] cycloaddition of azoalkenes with azlactones has been established. This convergent protocol leads to a facile and enantioselective de novo construction of a wide range of fully substituted 4-pyrrolin-2-ones bearing a fully substituted carbon atom in good yields and with excellent enantioselectivities (26 examples, 72-95% yields and 87-99% ee).

13.
Nurs Ethics ; 30(4): 585-597, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36888729

RESUMO

BACKGROUND: Moral courage is a recognized virtue. In the context of the COVID-19 pandemic, the master's students of nursing (MSNs) in China have shown tenacious moral courage. OBJECTIVE: This study elaborates on the moral courage of Chinese MSNs through their experiences of volunteering during the pandemic. RESEARCH DESIGN: Descriptive qualitative, interview-based. PARTICIPANTS AND RESEARCH CONTEXT: Participants were nursing postgraduate students who participated in the prevention and control of the COVID-19 pandemic selected by purposeful sampling. The sample size was determined by data saturation, which was reached with 10 participants. Data were analyzed using a deductive method of content analysis. Because of the isolation policy, telephone interviews were adopted. ETHICAL CONSIDERATIONS: After obtaining the approval of the ethical institution of the author's school (No. 138, 30 August 2021), verbal consent was obtained before the interview with the participants. All data were processed anonymously and confidentially. In addition, we recruited participants through MSNs' counselors, and obtained their phone numbers with their permission. RESULTS: Data analysis resulted in 15 subcategories that were subsequently grouped into 3 major categories including proceed without hesitation, the outcome of practicing moral courage, and develop and maintain moral courage. CONCLUSION: This qualitative study is based on the special background of the COVID-19 pandemic, and the MSNs in China have shown tenacious moral courage in the work of epidemic prevention and control. Five factors led them to take action without hesitation, and six possible outcomes followed. Lastly, this study provides some suggestions for nurses and nursing students to enhance their moral courage. To better develop and support moral courage in the future, it is necessary to use different methods and multidisciplinary approaches to study moral courage.


Assuntos
COVID-19 , Coragem , Ética em Enfermagem , Estudantes de Enfermagem , Humanos , Pandemias , Princípios Morais
14.
Nurs Open ; 10(7): 4305-4312, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-36811339

RESUMO

AIM: The purpose of this study was to assess the level of moral courage among nurses in China, and to explore related influential factors, to help nursing managers take measures to improve nurses' moral courage. DESIGN: A cross-sectional study. METHODS: The data adopted a convenient sampling method. From September to December 2021, 583 nurses from five hospitals in Fujian Province completed the Chinese version of the Nurses' Moral Courage Scale (NMCS). Data were analysed using descriptive statistics, chi-square test, T-test, Pearson correlation analysis and multiple regression analysis. RESULTS: The Chinese nurses perceived themselves, on average, as morally courageous. The mean NMCS score was 3.64 ± 0.692. The six factors showed statistically significant correlations (p < 0.05) with moral courage. Regression analysis showed that the main factors influencing nurses' moral courage were active learning of ethics knowledge and nursing was a career goal. CONCLUSION: This study provides the self-evaluation level and related influencing factors of Chinese nurses' moral courage. There is no doubt that nurses still need strong moral courage to face unknown ethical problems and challenges in the future. Nursing managers should pay attention to the cultivation of nurses' moral courage, using various forms of educational activities to help nurses alleviate moral problems and improve their moral courage, to maintain patients' access to high-quality nursing.


Assuntos
Coragem , Ética em Enfermagem , Enfermeiras e Enfermeiros , Humanos , Estudos Transversais , Princípios Morais , China
15.
Front Physiol ; 13: 1054773, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388120

RESUMO

To clarify the hormone control on sex determination and differentiation, we studied the Chinese mitten crab, Eriocheir sinensis (Henri Milne Edwards, 1854), a species with importantly economic and ecological significance. The crustacean female sex hormone (CFSH) and the insulin-like androgenic gland hormone (IAG) have been found to be related to the sex determination and/or differentiation. CFSH-1 of E. sinensis (EsCFSH-1) encoded a 227 amino-acid protein including a signal peptide, a CFSH-precursor-related peptide, and a mature CFSH peptide. Normally, EsCFSH-1 was highly expressed in the eyestalk ganglion of adult female crabs, while the expression was declined in the intersex crabs (genetic females). The intersex crabs had the androgenic glands, and the expression level of EsIAG was close to that of male crabs. During the embryogenesis and larval development, the changes of EsCFSH-1 and EsIAG genes expression in male and female individuals were shown after the zoea IV stage. Next, we confirmed the existence of the regulatory feedback loop between EsCFSH-1 and EsIAG by RNA interference experiment. The feminization function of EsCFSH-1 was further verified by examining the morphological change of external reproductive organs after EsCFSH-1 knockdown. The findings of this study reveal that the regulatory interplay between CFSH and IAG might play a pivotal role in the process of sex determination and/or differentiation in decapod crustaceans.

16.
J Clin Med ; 11(18)2022 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-36143037

RESUMO

Originally considered to be a plant pathogen, reports of phaeohyphomycosis due to Curvularia lunata (C. lunata) in animals and humans are increasing. However, studies on the pathogenesis, virulence, and epidemiology of C. lunata have rarely been discussed. In the present study, BALB/c mice were experimentally inoculated with C. lunata suspension by different routes and the course of infection was evaluated. In addition, the in vitro antifungal susceptibility of C. lunata against six commonly used antifungals was evaluated using the microdilution method. Inoculation resulted in skin lesions in animals inoculated intraperitonially and subcutaneously. Infection was confirmed by both mycological and histopathologic examination. C. lunata spores and hyphae were detected in the histopathologic sections stained with hexamine silver staining. In addition, voriconazole (VRC) demonstrated greater activity against C. lunata when compared to the other antifungals, whereas fluconazole (FLC) was the least active antifungal with a minimum inhibitory concentration (MIC) range of 8-16 µg/mL. Further studies are necessary to understand the pathogenicity of C. lunata and uncover the mystery of this fungus.

17.
Org Lett ; 24(35): 6397-6401, 2022 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-36018318

RESUMO

An asymmetric organocatalyzed three-component Povarov reaction to construct azaspirocycles has been developed. A chiral phosphoric acid OCF-CPA bearing o-CF3-aryl on the H8-BINOL-framework is highly efficient in the reaction. The reaction was carried out under mind conditions for synthesis of a range of azaspirocycles in high yields and high to excellent enantioselectivities, thus expending the substrate scope of the traditional Povarov reaction.


Assuntos
Estereoisomerismo , Catálise
18.
Chem Commun (Camb) ; 58(54): 7515-7518, 2022 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-35687078

RESUMO

A facile chiral phosphoric-acid catalyzed asymmetric inverse-electron-demand aza-Diels-Alder reaction of 1,3-diazadienes with 3-vinylindoles was established. By using this mild and practical protocol, a broad range of benzothiazolopyrimidines with three contiguous stereogenic centers were prepared in good yields and excellent diastereo- and enantio-selectivities (43 examples, up to 83% yield, >99% ee and all >20 : 1 dr). A plausible concerted reaction pathway enabled by the dual hydrogen-bonding effect was proposed to account for the observed excellent enantioselectivity and specific trans-trans diastereoselectivity.


Assuntos
Elétrons , Alcenos , Compostos Aza , Catálise , Reação de Cicloadição , Estereoisomerismo
19.
Geochem Trans ; 22(1): 1, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34037871

RESUMO

A complete series of calcite-rhodochrosite solid solutions [(Ca1-xMnx)CO3] are prepared, and their dissolution processes in various water samples are experimentally investigated. The crystal morphologies of the solid solutions vary from blocky spherical crystal aggregates to smaller spheres with an increasing incorporation of Mn in the solids. Regarding dissolution in N2-degassed water, air-saturated water and CO2-saturated water at 25 °C, the aqueous Ca and Mn concentrations reach their highest values after 1240-2400 h, 6-12 h and < 1 h, respectively, and then decrease gradually to a steady state; additionally, the ion activity products (log_IAP) at the final steady state (≈ solubility products in log_Ksp) are estimated to be - 8.46 ± 0.06, - 8.44 ± 0.10 and - 8.59 ± 0.10 for calcite [CaCO3], respectively, and - 10.25 ± 0.08, - 10.26 ± 0.10 and - 10.28 ± 0.03, for rhodochrosite [MnCO3], respectively. As XMn increases, the log_IAP values decrease from - 8.44 ~ - 8.59 for calcite to - 10.25 ~ - 10.28 for rhodochrosite. The aqueous Mn concentrations increase with an increasing Mn/(Ca + Mn) molar ratio (XMn) of the (Ca1-xMnx)CO3 solid solutions, while the aqueous Ca concentrations show the highest values at XMn = 0.53-0.63. In the constructed Lippmann diagram of subregular (Ca1-xMnx)CO3 solid solutions, the solids dissolve incongruently, and the data points of the aqueous solutions move progressively up to the Lippmann solutus curve and then along the solutus curve or saturation curve of pure MnCO3 to the Mn-poor side. The microcrystalline cores of the spherical crystal aggregates are preferentially dissolved to form core hollows while simultaneously precipitating Mn-rich hexagonal prisms.

20.
Oncol Lett ; 20(6): 308, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33093917

RESUMO

Aberrant DNA replication is one of the driving forces behind oncogenesis. Furthermore, minichromosome maintenance complex component 3 (MCM3) serves an essential role in DNA replication. Therefore, in the present study, the diagnostic and prognostic value of MCM3 and its interacting proteins in hepatocellular carcinoma (HCC) were investigated. By utilizing The Cancer Genome Atlas (TCGA) database, global MCM3 mRNA levels were assessed in HCC and normal liver tissues. Its effects were further analyzed by reverse transcription-quantitative PCR (RT-qPCR), western blotting and immunohistochemistry in 78 paired HCC and adjacent tissues. Functional and pathway enrichment analyses were performed using the Search Tool for the Retrieval of Interacting Genes database. The expression levels of proteins that interact with MCM3 were also analyzed using the TCGA database and RT-qPCR. Finally, algorithms combining receiver operating characteristic (ROC) curves were constructed using binary logistic regression using the TCGA results. Increased MCM3 mRNA expression with high α-fetoprotein levels and advanced Edmondson-Steiner grade were found to be characteristic of HCC. Survival analysis revealed that high MCM3 expression was associated with poor outcomes in patients with HCC. In addition, MCM3 protein expression was associated with increased tumor invasion in HCC tissues. MCM3 and its interacting proteins were found to be primarily involved in DNA replication, cell cycle and a number of binding processes. Algorithms combining ROCs of MCM3 and its interacting proteins were found to have improved HCC diagnosis ability compared with MCM3 and other individual diagnostic markers. In conclusion, MCM3 appears to be a promising diagnostic biomarker for HCC. Additionally, the present study provides a basis for the multi-gene diagnosis of HCC using MCM3.

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