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1.
Proc Natl Acad Sci U S A ; 121(30): e2405160121, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-38976765

RESUMO

Due to the scarcity of rock samples, the Hadean Era predating 4 billion years ago (Ga) poses challenges in understanding geological processes like subaerial weathering and plate tectonics that are critical for the evolution of life. The Jack Hills zircon from Western Australia, the primary Hadean samples available, offer valuable insights into magma sources and tectonic genesis through trace element signatures. However, a consensus on these signatures has not been reached. To address this, we developed a machine learning classifier capable of deciphering the geochemical fingerprints of zircon. This allowed us to identify the oldest detrital zircon originating from sedimentary-derived "S-type" granites. Our results indicate the presence of S-type granites as early as 4.24 Ga, persisting throughout the Hadean into the Archean. Examining global detrital zircon across Earth's history reveals consistent supercontinent-like cycles from the present back to the Hadean. These findings suggest that a significant amount of Hadean continental crust was exposed, weathered into sediments, and incorporated into the magma sources of Jack Hills zircon. Only the early operation of both subaerial weathering and plate subduction can account for the prevalence of S-type granites we observe. Additionally, the periodic evolution of S-type granite proportions implies that subduction-driven tectonic cycles were active during the Hadean, at least around 4.2 Ga. The evidence thus points toward an early Earth resembling the modern Earth in terms of active tectonics and habitable surface conditions. This suggests the potential for life to originate in environments like warm ponds rather than extreme hydrothermal settings.

2.
Circulation ; 150(2): 132-150, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557054

RESUMO

BACKGROUND: An imbalance of antiproliferative BMP (bone morphogenetic protein) signaling and proliferative TGF-ß (transforming growth factor-ß) signaling is implicated in the development of pulmonary arterial hypertension (PAH). The posttranslational modification (eg, phosphorylation and ubiquitination) of TGF-ß family receptors, including BMPR2 (bone morphogenetic protein type 2 receptor)/ALK2 (activin receptor-like kinase-2) and TGF-ßR2/R1, and receptor-regulated Smads significantly affects their activity and thus regulates the target cell fate. BRCC3 modifies the activity and stability of its substrate proteins through K63-dependent deubiquitination. By modulating the posttranslational modifications of the BMP/TGF-ß-PPARγ pathway, BRCC3 may play a role in pulmonary vascular remodeling, hence the pathogenesis of PAH. METHODS: Bioinformatic analyses were used to explore the mechanism by which BRCC3 deubiquitinates ALK2. Cultured pulmonary artery smooth muscle cells (PASMCs), mouse models, and specimens from patients with idiopathic PAH were used to investigate the rebalance between BMP and TGF-ß signaling in regulating ALK2 phosphorylation and ubiquitination in the context of pulmonary hypertension. RESULTS: BRCC3 was significantly downregulated in PASMCs from patients with PAH and animals with experimental pulmonary hypertension. BRCC3, by de-ubiquitinating ALK2 at Lys-472 and Lys-475, activated receptor-regulated Smad1/5/9, which resulted in transcriptional activation of BMP-regulated PPARγ, p53, and Id1. Overexpression of BRCC3 also attenuated TGF-ß signaling by downregulating TGF-ß expression and inhibiting phosphorylation of Smad3. Experiments in vitro indicated that overexpression of BRCC3 or the de-ubiquitin-mimetic ALK2-K472/475R attenuated PASMC proliferation and migration and enhanced PASMC apoptosis. In SM22α-BRCC3-Tg mice, pulmonary hypertension was ameliorated because of activation of the ALK2-Smad1/5-PPARγ axis in PASMCs. In contrast, Brcc3-/- mice showed increased susceptibility of experimental pulmonary hypertension because of inhibition of the ALK2-Smad1/5 signaling. CONCLUSIONS: These results suggest a pivotal role of BRCC3 in sustaining pulmonary vascular homeostasis by maintaining the integrity of the BMP signaling (ie, the ALK2-Smad1/5-PPARγ axis) while suppressing TGF-ß signaling in PASMCs. Such rebalance of BMP/TGF-ß pathways is translationally important for PAH alleviation.


Assuntos
Hipertensão Pulmonar , Músculo Liso Vascular , Miócitos de Músculo Liso , Animais , Humanos , Masculino , Camundongos , Receptores de Activinas Tipo II/metabolismo , Receptores de Activinas Tipo II/genética , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/metabolismo , Receptores de Proteínas Morfogenéticas Ósseas Tipo II/genética , Proliferação de Células , Células Cultivadas , Modelos Animais de Doenças , Hipertensão Pulmonar/metabolismo , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/patologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Músculo Liso Vascular/patologia , Miócitos de Músculo Liso/metabolismo , Miócitos de Músculo Liso/patologia , PPAR gama/metabolismo , PPAR gama/genética , Hipertensão Arterial Pulmonar/metabolismo , Hipertensão Arterial Pulmonar/patologia , Hipertensão Arterial Pulmonar/genética , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Transdução de Sinais , Ubiquitinação , Remodelação Vascular
3.
Nature ; 571(7764): 226-229, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31292556

RESUMO

The importance of highly siderophile elements (HSEs; namely, gold, iridium, osmium, palladium, platinum, rhenium, rhodium and ruthenium) in tracking the late accretion stages of planetary formation has long been recognized. However, the precise nature of the Moon's accretional history remains enigmatic. There is a substantial mismatch in the HSE budgets of the Earth and the Moon, with the Earth seeming to have accreted disproportionally more HSEs than the Moon1. Several scenarios have been proposed to explain this conundrum, including the delivery of HSEs to the Earth by a few big impactors1, the accretion of pebble-sized objects on dynamically cold orbits that enhanced the Earth's gravitational focusing factor2, and the 'sawtooth' impact model, with its much reduced impact flux before about 4.10 billion years ago3. However, most of these models assume a high impactor-retention ratio (the fraction of impactor mass retained on the target) for the Moon. Here we perform a series of impact simulations to quantify the impactor-retention ratio, followed by a Monte Carlo procedure considering a monotonically decaying impact flux4, to compute the impactor mass accreted into the lunar crust and mantle over their histories. We find that the average impactor-retention ratio for the Moon's entire impact history is about three times lower than previously estimated1,3. Our results indicate that, to match the HSE budgets of the lunar crust and mantle5,6, the retention of HSEs should have started 4.35 billion years ago, when most of the lunar magma ocean was solidified7,8. Mass accreted before this time must have lost its HSEs to the lunar core, presumably during lunar mantle crystallization9. The combination of a low impactor-retention ratio and a late retention of HSEs in the lunar mantle provides a realistic explanation for the apparent deficit of the Moon's late-accreted mass relative to that of the Earth.

4.
Mol Cell ; 67(2): 214-227.e7, 2017 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-28625552

RESUMO

Circular RNAs (circRNAs) generated via back-splicing are enhanced by flanking complementary sequences. Expression levels of circRNAs vary under different conditions, suggesting participation of protein factors in their biogenesis. Using genome-wide siRNA screening that targets all human unique genes and an efficient circRNA expression reporter, we identify double-stranded RNA-binding domain containing immune factors NF90/NF110 as key regulators in circRNA biogenesis. NF90/NF110 promote circRNA production in the nucleus by associating with intronic RNA pairs juxtaposing the circRNA-forming exon(s); they also interact with mature circRNAs in the cytoplasm. Upon viral infection, circRNA expression is decreased, in part owing to the nuclear export of NF90/NF110 to the cytoplasm. Meanwhile, NF90/NF110 released from circRNP complexes bind to viral mRNAs as part of their functions in antiviral immune response. Our results therefore implicate a coordinated regulation of circRNA biogenesis and function by NF90/NF110 in viral infection.


Assuntos
Núcleo Celular/metabolismo , Proteínas do Fator Nuclear 90/metabolismo , Ligação Proteica , RNA Mensageiro/metabolismo , RNA Viral/metabolismo , RNA/biossíntese , Viroses/metabolismo , Transporte Ativo do Núcleo Celular , Núcleo Celular/efeitos dos fármacos , Perfilação da Expressão Gênica , Células HEK293 , Células HeLa , Interações Hospedeiro-Patógeno , Humanos , Proteínas do Fator Nuclear 90/genética , Proteínas do Fator Nuclear 90/imunologia , Poli I-C/farmacologia , RNA/química , RNA/genética , Interferência de RNA , Processamento Pós-Transcricional do RNA , Splicing de RNA , Estabilidade de RNA , RNA Circular , RNA Mensageiro/genética , RNA Viral/genética , Transfecção , Viroses/genética , Viroses/imunologia
5.
Cancer Sci ; 2024 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-39318101

RESUMO

It is recognized that lncRNA BBOX1-AS1 exerts a crucial oncogenic property in several cancer types. However, the functions and underlying mechanisms of BBOX1-AS1 in the epithelial-mesenchymal transition (EMT) process of gastric cardia adenocarcinoma (GCA) have remained unclarified. The findings of this study demonstrated that GCA tissues had elevated BBOX1-AS1 expression levels, which was associated with a worse prognosis in GCA patients. BBOX1-AS1 dramatically enhanced cell proliferation, invasion, and TGF-ß1-induced the EMT process in vitro. Further mechanism analysis revealed that BBOX1-AS1 could combine with CtBP2 and strengthen the interaction of CtBP2 and ZEB1. BBOX1-AS1 might regulate the E-cadherin expression through CtBP2/ZEB1 transcriptional complex-mediated transcriptional repression, further affecting the activation of the Wnt/ß-catenin pathway and the EMT process. Overall, our findings demonstrate that BBOX1-AS1 might act as an lncRNA associated with EMT for facilitating GCA advancement via interaction with CtBP2 to facilitate the activation of Wnt/ß-catenin pathway and the EMT process, which indicated that it might function as an exploitable treatment target for GCA patients.

6.
Cell Commun Signal ; 22(1): 357, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38987851

RESUMO

BACKGROUND: Chronic kidney disease (CKD) is highly prevalent worldwide, and its global burden is substantial and growing. CKD displays a number of features of accelerated senescence. Tubular cell senescence is a common biological process that contributes to CKD progression. Tubulointerstitial inflammation is a driver of tubular cell senescence and a common characteristic of CKD. However, the mechanism by which the interstitial inflammation drives tubular cell senescence remains unclear. This paper aims to explore the role of exosomal miRNAs derived from macrophages in the development of tubular cell senescence. METHODS: Among the identified inflammation-related miRNAs, miR-155 is considered to be one of the most important miRNAs involved in the inflammatory response. Macrophages, the primary immune cells that mediate inflammatory processes, contain a high abundance of miR-155 in their released exosomes. We assessed the potential role of miR-155 in tubular cell senescence and renal fibrosis. We subjected miR-155-/- mice and wild-type controls, as well as tubular epithelial cells (TECs), to angiotensin II (AngII)-induced kidney injury. We assessed kidney function and injury using standard techniques. TECs were evaluated for cell senescence and telomere dysfunction in vivo and in vitro. Telomeres were measured by the fluorescence in situ hybridization. RESULTS: Compared with normal controls, miR-155 was up-regulated in proximal renal tubule cells in CKD patients and mouse models of CKD. Moreover, the expression of miR-155 was positively correlated with the extent of renal fibrosis, eGFR decline and p16INK4A expression. The overexpression of miR-155 exacerbated tubular senescence, evidenced by increased detection of p16INK4A/p21expression and senescence-associated ß-galactosidase activity. Notably, miR-155 knockout attenuates renal fibrosis and tubule cell senescence in vivo. Interestingly, once released, macrophages-derived exosomal miR-155 was internalized by TECs, leading to telomere shortening and dysfunction through targeting TRF1. A dual-luciferase reporter assay confirmed that TRF1 was the direct target of miR-155. Thus, our study clearly demonstrates that exosomal miR-155 may mediate communication between macrophages and TECs, subsequently inducing telomere dysfunction and senescence in TECs. CONCLUSIONS: Our work suggests a new mechanism by which macrophage exosomes are involved in the development of tubule senescence and renal fibrosis, in part by delivering miR-155 to target TRF1 to promote telomere dysfunction. Our study may provide novel strategies for the treatment of AngII-induced kidney injury.


Assuntos
Senescência Celular , Células Epiteliais , Exossomos , Túbulos Renais , Macrófagos , MicroRNAs , Telômero , MicroRNAs/genética , MicroRNAs/metabolismo , Senescência Celular/genética , Exossomos/metabolismo , Exossomos/genética , Animais , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Macrófagos/metabolismo , Túbulos Renais/patologia , Túbulos Renais/metabolismo , Camundongos , Telômero/genética , Telômero/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Masculino , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/patologia , Fibrose/genética , Angiotensina II
7.
Mol Cell ; 64(3): 534-548, 2016 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-27871485

RESUMO

We identify a type of polycistronic transcript-derived long noncoding RNAs (lncRNAs) that are 5' small nucleolar RNA (snoRNA) capped and 3' polyadenylated (SPAs). SPA processing is associated with nascent mRNA 3' processing and kinetic competition between XRN2 trimming and Pol II elongation. Following cleavage/polyadenylation of its upstream gene, the downstream uncapped pre-SPA is trimmed by XRN2 until this exonuclease reaches the co-transcriptionally assembled snoRNP. This snoRNP complex prevents further degradation, generates a snoRNA 5' end, and allows continuous Pol II elongation. The imprinted 15q11-q13 encodes two SPAs that are deleted in Prader-Willi syndrome (PWS) patients. These lncRNAs form a nuclear accumulation that is enriched in RNA binding proteins (RBPs) including TDP43, RBFOX2, and hnRNP M. Generation of a human PWS cellular model by depleting these lncRNAs results in altered patterns of RBPs binding and alternative splicing. Together, these results expand the diversity of lncRNAs and provide additional insights into PWS pathogenesis.


Assuntos
Sequência de Bases , Síndrome de Prader-Willi/genética , RNA Longo não Codificante/genética , RNA Nucleolar Pequeno/genética , Deleção de Sequência , Transcrição Gênica , Processamento Alternativo , Cromossomos Humanos Par 15 , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Exorribonucleases/genética , Exorribonucleases/metabolismo , Loci Gênicos , Impressão Genômica , Ribonucleoproteínas Nucleares Heterogêneas Grupo M/genética , Ribonucleoproteínas Nucleares Heterogêneas Grupo M/metabolismo , Células-Tronco Embrionárias Humanas/metabolismo , Células-Tronco Embrionárias Humanas/patologia , Humanos , Síndrome de Prader-Willi/metabolismo , Síndrome de Prader-Willi/patologia , Ligação Proteica , RNA Polimerase II/genética , RNA Polimerase II/metabolismo , Fatores de Processamento de RNA/genética , Fatores de Processamento de RNA/metabolismo , RNA Longo não Codificante/metabolismo , RNA Nucleolar Pequeno/metabolismo , Proteínas Repressoras/genética , Proteínas Repressoras/metabolismo
8.
Cell Mol Biol Lett ; 29(1): 69, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741032

RESUMO

BACKGROUND: Pulmonary hypertension (PH) is a progressive disease characterized by pulmonary vascular remodeling. Increasing evidence indicates that endothelial-to-mesenchymal transition (EndMT) in pulmonary artery endothelial cells (PAECs) is a pivotal trigger initiating this remodeling. However, the regulatory mechanisms underlying EndMT in PH are still not fully understood. METHODS: Cytokine-induced hPAECs were assessed using RNA methylation quantification, qRT-PCR, and western blotting to determine the involvement of N6-methyladenosine (m6A) methylation in EndMT. Lentivirus-mediated silencing, overexpression, tube formation, and wound healing assays were utilized to investigate the function of METTL3 in EndMT. Endothelial-specific gene knockout, hemodynamic measurement, and immunostaining were performed to explore the roles of METTL3 in pulmonary vascular remodeling and PH. RNA-seq, RNA Immunoprecipitation-based qPCR, mRNA stability assay, m6A mutation, and dual-luciferase assays were employed to elucidate the mechanisms of RNA methylation in EndMT. RESULTS: The global levels of m6A and METTL3 expression were found to decrease in TNF-α- and TGF-ß1-induced EndMT in human PAECs (hPAECs). METTL3 inhibition led to reduced endothelial markers (CD31 and VE-cadherin) and increased mesenchymal markers (SM22 and N-cadherin) as well as EndMT-related transcription factors (Snail, Zeb1, Zeb2, and Slug). The endothelial-specific knockout of Mettl3 promoted EndMT and exacerbated pulmonary vascular remodeling and hypoxia-induced PH (HPH) in mice. Mechanistically, METTL3-mediated m6A modification of kruppel-like factor 2 (KLF2) plays a crucial role in the EndMT process. KLF2 overexpression increased CD31 and VE-cadherin levels while decreasing SM22, N-cadherin, and EndMT-related transcription factors, thereby mitigating EndMT in PH. Mutations in the m6A site of KLF2 mRNA compromise KLF2 expression, subsequently diminishing its protective effect against EndMT. Furthermore, KLF2 modulates SM22 expression through direct binding to its promoter. CONCLUSIONS: Our findings unveil a novel METTL3/KLF2 pathway critical for protecting hPAECs against EndMT, highlighting a promising avenue for therapeutic investigation in PH.


Assuntos
Adenosina , Células Endoteliais , Transição Epitelial-Mesenquimal , Hipertensão Pulmonar , Fatores de Transcrição Kruppel-Like , Metiltransferases , Animais , Humanos , Camundongos , Adenosina/análogos & derivados , Adenosina/metabolismo , Caderinas/metabolismo , Caderinas/genética , Células Cultivadas , Células Endoteliais/metabolismo , Transição Epitelial-Mesenquimal/genética , Hipertensão Pulmonar/genética , Hipertensão Pulmonar/metabolismo , Fatores de Transcrição Kruppel-Like/metabolismo , Fatores de Transcrição Kruppel-Like/genética , Metilação , Metiltransferases/metabolismo , Metiltransferases/genética , Camundongos Endogâmicos C57BL , Artéria Pulmonar/metabolismo , Artéria Pulmonar/patologia , Remodelação Vascular/genética
9.
Artigo em Inglês | MEDLINE | ID: mdl-38861168

RESUMO

Although it is well recognized that autism spectrum disorder (ASD) is associated with atypical dynamic functional connectivity patterns, the dynamic changes in brain intrinsic activity over each time point and the potential molecular mechanisms associated with atypical dynamic temporal characteristics in ASD remain unclear. Here, we employed the Hidden Markov Model (HMM) to explore the atypical neural configuration at every scanning time point in ASD, based on resting-state functional magnetic resonance imaging (rs-fMRI) data from the Autism Brain Imaging Data Exchange. Subsequently, partial least squares regression and pathway enrichment analysis were employed to explore the potential molecular mechanism associated with atypical neural dynamics in ASD. 8 HMM states were inferred from rs-fMRI data. Compared to typically developing, individuals on the autism spectrum showed atypical state-specific temporal characteristics, including number of states and occurrences, mean life time and transition probability between states. Moreover, these atypical temporal characteristics could predict communication difficulties of ASD, and states assoicated with negative activation in default mode network and frontoparietal network, and positive activation in somatomotor network, ventral attention network, and limbic network, had higher predictive contribution. Furthermore, a total of 321 genes was revealed to be significantly associated with atypical dynamic brain states of ASD, and these genes are mainly enriched in neurodevelopmental pathways. Our study provides new insights into characterizing the atypical neural dynamics from a moment-to-moment perspective, and indicates a linkage between atypical neural configuration and gene expression in ASD.

10.
Int J Nurs Pract ; 30(3): e13226, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38128910

RESUMO

BACKGROUND: The high incidence of malnutrition in patients undergoing colorectal cancer surgery can lead to unplanned weight loss, sarcopenia and reduced grip strength to the extent that it can seriously affect the prognosis of colorectal cancer patients. OBJECTIVE: This study investigated the effect of oral nutritional supplements (ONS) on the prevalence of grip strength, unplanned weight loss and sarcopenia in patients undergoing colorectal cancer surgery. METHODS: We systematically searched randomized controlled studies from CINAHL, PubMed, Embase, Cochrane and Web of Science and three Chinese databases (CNKI, Wan-Fang database, VIP database) from database creation to September 2023. The risk of bias in individual studies was assessed using the Cochrane Collaboration tool, and the certainty of evidence was assessed using the five GRADE criteria. Statistical analysis was performed using the RevMan 5.3 software, and information that could not be meta-analysed was reviewed in the form of a literature summary. RESULTS: Eleven papers met the inclusion criteria with a combined sample size of 1070 cases, including 532 cases in the trial group and 538 cases in the control group. Four papers reported the effect of ONS on grip strength and included very low-quality evidence supporting no effect of ONS on grip strength. Ten studies reported the effect of ONS on body weight and body mass index (BMI) and included very low-quality evidence supporting a positive ONS on weight and BMI changes. Meta-analysis showed a significant reduction in weight loss (12-15 weeks) and BMI loss (12-15 weeks) in patients with colorectal cancer in the ONS group. The effect of ONS on the prevalence of sarcopenia after hospital discharge was reported in two studies, and meta-analysis showed a significant reduction in the prevalence of postoperative sarcopenia in colorectal cancer patients in the ONS group, but the quality of evidence was low. CONCLUSIONS: This study showed that the use of ONS in patients undergoing surgery for colorectal cancer improved patient weight loss and BMI reduction and reduced the prevalence of postoperative sarcopenia but did not improve patient grip strength. The quality of evidence for inclusion in the article was low or very low, and further studies are needed to provide better evidence.


Assuntos
Neoplasias Colorretais , Suplementos Nutricionais , Estado Nutricional , Humanos , Neoplasias Colorretais/cirurgia , Sarcopenia/epidemiologia , Ensaios Clínicos Controlados Aleatórios como Assunto , Força da Mão , Desnutrição/prevenção & controle , Desnutrição/epidemiologia , Redução de Peso
11.
Zhongguo Zhong Yao Za Zhi ; 49(5): 1260-1265, 2024 Mar.
Artigo em Zh | MEDLINE | ID: mdl-38621973

RESUMO

A variety of compounds in Artemisia annua were simultaneously determined to evaluate the quality of A. annua from multiple perspectives. A method based on ultra-high performance liquid chromatography-triple quadrupole tandem mass spectrometry(UPLC-QQQ-MS/MS) was established for the simultaneous determination of seven compounds: amorpha-4,11-diene, artemisinic aldehyde, dihydroartemisinic acid, artemisinic acid, artemisinin B, artemisitene, and artemisinin, in A. annua. The content of the seven compounds in different tissues(roots, stems, leaves, and lateral branches) of A. annua were compared. The roots, stems, leaves, and lateral branches of four-month-old A. annua were collected and the content of seven artemisinin-related compounds in different tissues was determined. A multi-reaction monitoring(MRM) acquisition mode of UPLC-QQQ-MS/MS was used, with a positive ion mode of atmospheric pressure chemical ion source(APCI). Chromatographic separation was achieved on an Eclipse Plus RRHD C_(18) column(2.1 mm×50 mm, 1.8 µm). The gradient elution was performed with the mobile phase consisted of formic acid(0.1%)-ammonium formate(5 mmol·L~(-1))(A) and the methanol(B) gradient program of 0-8 min, 55%-100% B, 8-11 min, 100% B, and equilibrium for 3 min, the flow rate of 0.6 mL·min~(-1), the column temperature of 40 ℃, the injection volume of 5 µL, and the detection time of 8 min. Through methodological investigation, a method based on UPLC-QQQ-MS/MS was established for the simultaneous quantitative determination of seven representative compounds involved in the biosynthesis of artemisinin. The content of artemisinin in A. annua was higher than that of artemisinin B, and the content of artemisinin and dihydroartemisinic acid were high in all the tissues of A. annua. The content of the seven compounds varied considerably in different tissues, with the highest levels in the leaves and neither artemisinene nor artemisinic aldehyde was detected in the roots. In this study, a quantitative method based on UPLC-QQQ-MS/MS for the simultaneous determination of seven representative compounds involved in the biosynthesis of artemisinin was established, which was accurate, sensitive, and highly efficient, and can be used for determining the content of artemisinin-related compounds in A. annua, breeding new varieties, and controlling the quality of Chinese medicinal materials.


Assuntos
Artemisia annua , Artemisininas , Lactonas , Artemisia annua/química , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Melhoramento Vegetal , Artemisininas/análise , Aldeídos
12.
Zhongguo Zhong Yao Za Zhi ; 49(6): 1641-1660, 2024 Mar.
Artigo em Zh | MEDLINE | ID: mdl-38621949

RESUMO

This study explored the existence forms(original constituents and metabolites) of Tiantian Capsules, Aloe, and Tiantian Capsules without Aloe in rats for the first time, aiming to clarify the contribution of Aloe to the existence form of Tiantian Capsules. Rats were administrated with corresponding drugs by gavage once a day for seven consecutive days. All urine and feces samples were collected during the seven days of administration, and blood samples were collected 0.5, 1, and 1.5 h after the last administration. UHPLC-Q-TOF-MS was employed to detect and identify the original constituents and metabolites in the samples. A total of 34, 28, and 2 original constituents and 64, 94, and 0 metabolites were identified in the samples of rats administrated with Aloe, Tiantian Capsules, and Tiantian Capsules without Aloe, respectively. The main metabolic reactions were methylation, hydrogenation, hydroxylation, dehydroxylation, glucuronidation, and sulfation. This study clarified for the first time the existence forms and partial metabolic pathways of Aloe, Tiantian Capsules, and Tiantian Capsules without Aloe in rats, laying a foundation for revealing their effective forms. The findings are of great significance to the research on the functioning mechanism and quality control of Aloe and Tiantian Capsules.


Assuntos
Aloe , Medicamentos de Ervas Chinesas , Ratos , Animais , Cromatografia Líquida de Alta Pressão , Medicamentos de Ervas Chinesas/metabolismo , Administração Oral , Fezes , Cápsulas
13.
Semin Cancer Biol ; 85: 123-154, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33992782

RESUMO

The RAF-MEK-ERK signaling cascade is a well-characterized MAPK pathway involved in cell proliferation and survival. The three-layered MAPK signaling cascade is initiated upon RTK and RAS activation. Three RAF isoforms ARAF, BRAF and CRAF, and their downstream MEK1/2 and ERK1/2 kinases constitute a coherently orchestrated signaling module that directs a range of physiological functions. Genetic alterations in this pathway are among the most prevalent in human cancers, which consist of numerous hot-spot mutations such as BRAFV600E. Oncogenic mutations in this pathway often override otherwise tightly regulated checkpoints to open the door for uncontrolled cell growth and neoplasia. The crosstalk between the RAF-MEK-ERK axis and other signaling pathways further extends the proliferative potential of this pathway in human cancers. In this review, we summarize the molecular architecture and physiological functions of the RAF-MEK-ERK pathway with emphasis on its dysregulations in human cancers, as well as the efforts made to target the RAF-MEK-ERK module using small molecule inhibitors.


Assuntos
Sistema de Sinalização das MAP Quinases , Neoplasias , Humanos , Proteínas Proto-Oncogênicas B-raf/metabolismo , Neoplasias/tratamento farmacológico , Neoplasias/genética , Transdução de Sinais , Quinases de Proteína Quinase Ativadas por Mitógeno/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/metabolismo
14.
Small ; 19(43): e2302896, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37376841

RESUMO

Chloride-ion batteries (CIBs) have drawn growing attention in large-scale energy storage applications owing to their comprehensive merits of high theoretical energy density, dendrite-free characteristic, and abundance of chloride-containing materials. Nonetheless, cathodes for CIBs are plagued by distinct volume effect and sluggish Cl- diffusion kinetics, leading to inferior rate capability and short cycling life. Herein, an unconventional Ni5 Ti-Cl LDH is reported with a high nickel ratio as a cathode material for CIB. The reversible capacity of Ni5 Ti-Cl LDH retains 127.9 mAh g-1 over 1000 cycles at a large current density of 1000 mA g-1 , which exceeds that of ever reported CIBs, with extraordinary low volume change of 1.006% during a whole charge/discharge process. Such superior Cl-storage performance is attributed to synergetic contributions consisting of high redox activity from Ni2+ /Ni3+ and pinning Ti that restrains local structural distortion of LDH host layers and enhances adsorption intensity of chloride atoms during the reversible Cl- intercalation/de-intercalation in LDH gallery, which are revealed by a comprehensive study including X-ray photoelectron spectroscopy, kinetic investigations, and DFT calculations. This work provides an effective strategy to design low-cost LDHs materials for high-performance CIBs, which are also applicable to other types of halide-ion batteries (e.g., fluoride-ion and bromide-ion batteries).

15.
Mol Ther ; 30(10): 3300-3312, 2022 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-35581939

RESUMO

Cyclin-dependent kinase 12 (CDK12) plays a critical role in regulating gene transcription. CDK12 inhibition is a potential anticancer therapeutic strategy. However, several clinical trials have shown that CDK inhibitors might cause renal dysfunction and electrolyte disorders. CDK12 is abundant in renal tubular epithelial cells (RTECs), but the exact role of CDK12 in renal physiology remains unclear. Genetic knockout of CDK12 in mouse RTECs causes polydipsia, polyuria, and hydronephrosis. This phenotype is caused by defects in water reabsorption that are the result of reduced Na-K-2Cl cotransporter 2 (NKCC2) levels in the kidney. In addition, CKD12 knockout causes an increase in Slc12a1 (which encodes NKCC2) intronic polyadenylation events, which results in Slc12a1 truncated transcript production and NKCC2 downregulation. These findings provide novel insight into CDK12 being necessary for maintaining renal homeostasis by regulating NKCC2 transcription, which explains the critical water and electrolyte disturbance that occurs during the application of CDK12 inhibitors for cancer treatment. Therefore, there are safety concerns about the clinical use of these new anticancer drugs.


Assuntos
Antineoplásicos , Simportadores , Animais , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Eletrólitos , Rim/metabolismo , Camundongos , Membro 1 da Família 12 de Carreador de Soluto , Simportadores/genética , Água
16.
Proc Natl Acad Sci U S A ; 117(38): 23426-23435, 2020 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-32900966

RESUMO

Dynamic models of the protoplanetary disk indicate there should be large-scale material transport in and out of the inner Solar System, but direct evidence for such transport is scarce. Here we show that the ε50Ti-ε54Cr-Δ17O systematics of large individual chondrules, which typically formed 2 to 3 My after the formation of the first solids in the Solar System, indicate certain meteorites (CV and CK chondrites) that formed in the outer Solar System accreted an assortment of both inner and outer Solar System materials, as well as material previously unidentified through the analysis of bulk meteorites. Mixing with primordial refractory components reveals a "missing reservoir" that bridges the gap between inner and outer Solar System materials. We also observe chondrules with positive ε50Ti and ε54Cr plot with a constant offset below the primitive chondrule mineral line (PCM), indicating that they are on the slope ∼1.0 in the oxygen three-isotope diagram. In contrast, chondrules with negative ε50Ti and ε54Cr increasingly deviate above from PCM line with increasing δ18O, suggesting that they are on a mixing trend with an ordinary chondrite-like isotope reservoir. Furthermore, the Δ17O-Mg# systematics of these chondrules indicate they formed in environments characterized by distinct abundances of dust and H2O ice. We posit that large-scale outward transport of nominally inner Solar System materials most likely occurred along the midplane associated with a viscously evolving disk and that CV and CK chondrules formed in local regions of enhanced gas pressure and dust density created by the formation of Jupiter.

17.
Knee Surg Sports Traumatol Arthrosc ; 31(1): 70-78, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35687148

RESUMO

PURPOSE: To investigate the thickness and intra-substance change of anterior capsule of the hip joint, and compare the difference of the capsular features in patients with different statuses of hip stability. METHODS: A retrospective study was performed to review a hip preservation database. Using the lateral center edge angle(LCEA), patients with borderline dysplasia of the hip (BDH) of 20° ≤ LCEA ≤ 25°, femoracetabular impingement(FAI) with LCEA > 30° and dysplasia of the hip (DH) of LCEA < 20° were enrolled and stratified into different treatment groups. The patients' imaging was reviewed by two experienced musculoskeletal radiologists who were blinded to clinical outcomes. Thickness and intra-substance change of the anterior hip capsule was measured on the sagittal oblique sequences of MRI. A surgeon measured the thickness of the anterior hip capsule during arthroscopy. The capsular thickness and intra-substance change were compared among different groups. RESULTS: Thirty patients (17 women and 13 men) enrolled in each group (FAI, BDH, and DH) matched by sex and ages were evaluated. There were no significant differences in terms of age, sex, BMI, Alpha angle, and Tönnis grade among all three groups. The mean thickness of the anterior capsule in the DH group was 3.2 ± 0.5 mm, which was significantly thinner than that in the BDH and FAI groups (4.5 ± 0.8 mm and 4.7 ± 0.6 mm), and there was no significant difference in capsular thickness between the BDH and FAI groups. The Median of anterior capsule thickness via arthroscopic measuring was 6 mm and 7 mm in the BDH and FAI groups respectively, which has no statistical difference. The intra-substance change of the anterior capsule shows a significant difference among the three groups, and a higher incidence of delamination of the capsule was found in DH groups (p < 0.001). CONCLUSIONS: Patients with hip dysplasia have a significantly reduced capsular thickness on MRI and delaminated anterior joint capsule, which could be a sequence of instability. The clinical relevance of this study is that capsular thickness and intra-substance changes of the anterior capsule vary which could alter capsular management strategies. LEVEL OF EVIDENCE: Level III of evidence, DIAGNOSTIC STUDIES, No consistently applied reference standard.


Assuntos
Impacto Femoroacetabular , Luxação Congênita de Quadril , Luxação do Quadril , Masculino , Humanos , Feminino , Adulto Jovem , Estudos Retrospectivos , Luxação Congênita de Quadril/diagnóstico por imagem , Luxação Congênita de Quadril/cirurgia , Articulação do Quadril/diagnóstico por imagem , Articulação do Quadril/cirurgia , Impacto Femoroacetabular/diagnóstico por imagem , Impacto Femoroacetabular/cirurgia , Luxação do Quadril/diagnóstico por imagem , Luxação do Quadril/cirurgia , Artroscopia/métodos , Resultado do Tratamento
18.
BMC Med Educ ; 23(1): 546, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37528406

RESUMO

BACKGROUND: This meta-analysis was conducted to systematically evaluate the impact of problem-based learning (PBL) and lecture-based learning (LBL) teaching models on students' learning in surgical education. METHODS: We systematically searched the publications related to the application of PBL and LBL in surgical courses in PubMed, Embase, Web of Science and Cochrane Library databases, the last retrieval time is September 20, 2022. After screening the literature according to the inclusion and exclusion criteria, extracting data and evaluating the methodological treatment of the included studies, Stata 17.0 software was used to perform meta-analysis. RESULTS: Nine studies were included totally. The results showed that compared with LBL, PBL was superior in clinical competence (SMD = 0.81, 95% CI: 0.12 ~ 1.49, P = 0.020) and student satisfaction (SMD = 2.13, 95% CI: 1.11 ~ 3.15, P < 0.0001) with significant differences. But the comprehensive scores (SMD = 0.26, 95% CI: -0.37 ~ 0.89, P = 0.421) and theoretical knowledge (SMD=-0.19, 95% CI: -0.71 ~ 0.33, P = 0.482) to PBL and LBL had no significant difference. CONCLUSION: This study showed that the PBL teaching model is more effective than the LBL teaching model in surgical education on the aspects of enhancing clinical competence and student satisfaction. However, further well-designed studies are needed to confirm our findings.


Assuntos
Educação Médica , Aprendizagem Baseada em Problemas , Humanos , Aprendizagem Baseada em Problemas/métodos , Avaliação Educacional , Estudantes , Educação Médica/métodos , Competência Clínica
19.
J Perianesth Nurs ; 38(5): 787-791, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37269278

RESUMO

PURPOSE: Some patients experience sleep disturbances after endoscopy performed under sedation. This study aimed to evaluate the effects of propofol on sleep quality after gastrointestinal endoscopy (GE). DESIGN: This study was a prospective cohort study. METHODS: This study enrolled 880 patients who underwent GE. Patients who chose to undergo GE under sedation received intravenous propofol, whereas the control group did not. The Pittsburgh Sleep Quality Index (PSQI) was measured before GE (PSQI-1) and 3 weeks (PSQI-2) after GE. The Groningen Sleep Score Scale (GSQS) was used before GE (GSQS-1) and 1 (GSQS-2) and 7 days (GSQS-3) after GE. FINDINGS: There was a significant increase in GSQS scores from baseline to days 1 and 7 after GE (GSQS-2 vs GSQS-1, P < .001, GSQS-3 vs GSQS-1, P = .008). However, no significant changes were observed in the control group (GSQS-2 vs GSQS-1, P = .38, GSQS-3 vs GSQS-1, P = .66). On day 21, there were no significant changes in the baseline PSQI scores over time in either group (sedation group, P = .96; control group, P = .95). CONCLUSIONS: GE with propofol sedation negatively affected sleep quality for 7 days after GE but not 3 weeks after GE.


Assuntos
Propofol , Humanos , Propofol/efeitos adversos , Qualidade do Sono , Estudos Prospectivos , Endoscopia Gastrointestinal , Administração Intravenosa
20.
Zhongguo Zhong Yao Za Zhi ; 48(19): 5181-5194, 2023 Oct.
Artigo em Zh | MEDLINE | ID: mdl-38114108

RESUMO

Artemisia argyi is an important medicinal and economic plant in China, with the effects of warming channels, dispersing cold, and relieving pain, inflammation, and allergy. The essential oil of this plant is rich in volatile terpenoids and widely used in moxi-bustion and healthcare products, with huge market potential. The bZIP transcription factors compose a large family in plants and are involved in the regulation of plant growth and development, stress response, and biosynthesis of secondary metabolites such as terpenoids. However, little is known about the bZIPs and their roles in A. argyi. In this study, the bZIP transcription factors in the genome of A. argyi were systematically identified, and their physicochemical properties, phylogenetic relationship, conserved motifs, and promoter-binding elements were analyzed. Candidate AarbZIP genes involved in terpenoid biosynthesis were screened out. The results showed that a total of 156 AarbZIP transcription factors were identified at the genomic level, with the lengths of 99-618 aa, the molecular weights of 11.7-67.8 kDa, and the theoretical isoelectric points of 4.56-10.16. According to the classification of bZIPs in Arabidopsis thaliana, the 156 AarbZIPs were classified into 12 subfamilies, and the members in the same subfamily had similar conserved motifs. The cis-acting elements of promoters showed that AarbZIP genes were possibly involved in light and hormonal pathways. Five AarbZIP genes that may be involved in the regulation of terpenoid biosynthesis were screened out by homologous alignment and phylogenetic analysis. The qRT-PCR results showed that the expression levels of the five AarbZIP genes varied significantly in different tissues of A. argyi. Specifically, AarbZIP29 and AarbZIP55 were highly expressed in the leaves and AarbZIP81, AarbZIP130, and AarbZIP150 in the flower buds. This study lays a foundation for the functional study of bZIP genes and their regulatory roles in the terpenoid biosynthesis in A. argyi.


Assuntos
Artemisia , Perfilação da Expressão Gênica , Filogenia , Artemisia/genética , Fatores de Transcrição de Zíper de Leucina Básica/genética , Fatores de Transcrição de Zíper de Leucina Básica/metabolismo , Terpenos , Regulação da Expressão Gênica de Plantas
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