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1.
J Biol Chem ; 300(4): 106791, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38403247

RESUMO

DNA modifications add another layer of complexity to the eukaryotic genome to regulate gene expression, playing critical roles as epigenetic marks. In eukaryotes, the study of DNA epigenetic modifications has been confined to 5mC and its derivatives for decades. However, rapid developing approaches have witnessed the expansion of DNA modification reservoirs during the past several years, including the identification of 6mA, 5gmC, 4mC, and 4acC in diverse organisms. However, whether these DNA modifications function as epigenetic marks requires careful consideration. In this review, we try to present a panorama of all the DNA epigenetic modifications in eukaryotes, emphasizing recent breakthroughs in the identification of novel DNA modifications. The characterization of their roles in transcriptional regulation as potential epigenetic marks is summarized. More importantly, the pathways for generating or eliminating these DNA modifications, as well as the proteins involved are comprehensively dissected. Furthermore, we briefly discuss the potential challenges and perspectives, which should be taken into account while investigating novel DNA modifications.


Assuntos
Metilação de DNA , Epigênese Genética , Eucariotos , Humanos , Eucariotos/genética , Eucariotos/metabolismo , Animais , DNA/metabolismo , DNA/genética , DNA/química
2.
Nature ; 569(7757): 581-585, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-31043749

RESUMO

Methylation of cytosine to 5-methylcytosine (5mC) is a prevalent DNA modification found in many organisms. Sequential oxidation of 5mC by ten-eleven translocation (TET) dioxygenases results in a cascade of additional epigenetic marks and promotes demethylation of DNA in mammals1,2. However, the enzymatic activity and function of TET homologues in other eukaryotes remains largely unexplored. Here we show that the green alga Chlamydomonas reinhardtii contains a 5mC-modifying enzyme (CMD1) that is a TET homologue and catalyses the conjugation of a glyceryl moiety to the methyl group of 5mC through a carbon-carbon bond, resulting in two stereoisomeric nucleobase products. The catalytic activity of CMD1 requires Fe(II) and the integrity of its binding motif His-X-Asp, which is conserved in Fe-dependent dioxygenases3. However, unlike previously described TET enzymes, which use 2-oxoglutarate as a co-substrate4, CMD1 uses L-ascorbic acid (vitamin C) as an essential co-substrate. Vitamin C donates the glyceryl moiety to 5mC with concurrent formation of glyoxylic acid and CO2. The vitamin-C-derived DNA modification is present in the genome of wild-type C. reinhardtii but at a substantially lower level in a CMD1 mutant strain. The fitness of CMD1 mutant cells during exposure to high light levels is reduced. LHCSR3, a gene that is critical for the protection of C. reinhardtii from photo-oxidative damage under high light conditions, is hypermethylated and downregulated in CMD1 mutant cells compared to wild-type cells, causing a reduced capacity for photoprotective non-photochemical quenching. Our study thus identifies a eukaryotic DNA base modification that is catalysed by a divergent TET homologue and unexpectedly derived from vitamin C, and describes its role as a potential epigenetic mark that may counteract DNA methylation in the regulation of photosynthesis.


Assuntos
5-Metilcitosina/metabolismo , Proteínas de Algas/metabolismo , Ácido Ascórbico/metabolismo , Biocatálise , Chlamydomonas reinhardtii/enzimologia , DNA/química , DNA/metabolismo , 5-Metilcitosina/química , Dióxido de Carbono/metabolismo , Metilação de DNA , Glioxilatos/metabolismo , Nucleosídeos/química , Nucleosídeos/metabolismo , Fotossíntese
3.
J Antimicrob Chemother ; 79(7): 1606-1613, 2024 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-38804142

RESUMO

BACKGROUND: The efficacy of current drugs against hookworms at a single dose is highly variable across regions, age groups and infection intensity. Extensive and repeated use of these drugs also leads to potential drug resistance. Therefore, novel drugs are required for sustained disease control. OBJECTIVES: Novel aromatic heterocycle substituted aminamidine derivatives (AADs) were synthesized based on tribendimine (TBD), and their in vivo potency against Necator americanus was tested. METHODS: The efficacy of the AADs was tested in male hamsters. Oral and IV pharmacokinetic parameters were determined in male Sprague-Dawley rats. The proteomic profiles of N. americanus samples treated with AADs were compared using tandem mass tag-based quantitative proteomic analyses. RESULTS: Most AADs exhibited better anthelmintic activity than TBD at a single oral dose. Compound 3c exhibited improved solubility (>50×), and the curative dose was as low as 25 mg/kg. Similar to TBD, 3c was rapidly metabolized after oral administration and transformed into p-(1-dimethylamino ethylimino)aniline (dADT), an active metabolite against intestinal nematodes. dADT from 3c had better pharmacokinetic profiles than that from TBD and achieved an oral bioavailability of 99.5%. Compound 3c possessed rapid anthelmintic activity, clearing all worms within 24 h after an oral dose of 50 mg/kg. Quantitative proteomic analysis indicated that it might be related to ATP metabolism and cuticle protein synthesis. CONCLUSIONS: Compound 3c is a novel and promising compound against N. americanus in vivo.


Assuntos
Anti-Helmínticos , Necator americanus , Ratos Sprague-Dawley , Animais , Masculino , Anti-Helmínticos/farmacologia , Anti-Helmínticos/farmacocinética , Necator americanus/efeitos dos fármacos , Amidinas/farmacologia , Amidinas/farmacocinética , Administração Oral , Cricetinae , Ratos , Compostos Heterocíclicos/farmacologia , Compostos Heterocíclicos/farmacocinética , Compostos Heterocíclicos/química , Proteômica
4.
Acta Pharmacol Sin ; 45(10): 2061-2076, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38789495

RESUMO

Paclitaxel (PTX) serves as a primary chemotherapy agent against diverse solid tumors including breast cancer, lung cancer, head and neck cancer and ovarian cancer, having severe adverse effects including PTX-induced peripheral neuropathy (PIPN) and hypersensitivity reactions (HSR). A recommended anti-allergic agent diphenhydramine (DIP) has been used to alleviate PTX-induced HSR. Desloratadine (DLT) is a third generation of histamine H1 receptor antagonist, but also acted as a selective antagonist of 5HTR2A. In this study we investigated whether DLT ameliorated PIPN-like symptoms in mice and the underlying mechanisms. PIPN was induced in male mice by injection of PTX (4 mg/kg, i.p.) every other day for 4 times. The mice exhibited 50% reduction in mechanical threshold, paw thermal response latency and paw cold response latency compared with control mice. PIPN mice were treated with DLT (10, 20 mg/kg, i.p.) 30 min before each PTX administration in the phase of establishing PIPN mice model and then administered daily for 4 weeks after the model was established. We showed that DLT administration dose-dependently elevated the mechanical, thermal and cold pain thresholds in PIPN mice, whereas administration of DIP (10 mg/kg, i.p.) had no ameliorative effects on PIPN-like symptoms. We found that the expression of 5HTR2A was selectively elevated in the activated spinal astrocytes of PIPN mice. Spinal cord-specific 5HTR2A knockdown by intrathecal injection of AAV9-5Htr2a-shRNA significantly alleviated the mechanical hyperalgesia, thermal and cold hypersensitivity in PIPN mice, while administration of DLT (20 mg/kg) did not further ameliorate PIPN-like symptoms. We demonstrated that DLT administration alleviated dorsal root ganglion neuronal damage and suppressed sciatic nerve destruction, spinal neuron apoptosis and neuroinflammation in the spinal cord of PIPN mice. Furthermore, we revealed that DLT administration suppressed astrocytic neuroinflammation via the 5HTR2A/c-Fos/NLRP3 pathway and blocked astrocyte-neuron crosstalk by targeting 5HTR2A. We conclude that spinal 5HTR2A inhibition holds promise as a therapeutic approach for PIPN and we emphasize the potential of DLT as a dual-functional agent in ameliorating PTX-induced both PIPN and HSR in chemotherapy. In summary, we determined that spinal 5HTR2A was selectively activated in PIPN mice and DLT could ameliorate the PTX-induced both PIPN- and HSR-like pathologies in mice. DLT alleviated the damages of DRG neurons and sciatic nerves, while restrained spinal neuronal apoptosis and CGRP release in PIPN mice. The underlying mechanisms were intensively investigated by assay against the PIPN mice with 5HTR2A-specific knockdown in the spinal cord by injection of adeno-associated virus 9 (AAV9)-5Htr2a-shRNA. DLT inhibited astrocytic NLRP3 inflammasome activation-mediated spinal neuronal damage through 5HTR2A/c-FOS pathway. Our findings have supported that spinal 5HTR2A inhibition shows promise as a therapeutic strategy for PIPN and highlighted the potential advantage of DLT as a dual-functional agent in preventing against PTX-induced both PIPN and HSR effects in anticancer chemotherapy.


Assuntos
Loratadina , Paclitaxel , Doenças do Sistema Nervoso Periférico , Animais , Masculino , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/tratamento farmacológico , Camundongos , Paclitaxel/efeitos adversos , Loratadina/análogos & derivados , Loratadina/farmacologia , Loratadina/uso terapêutico , Antineoplásicos Fitogênicos/farmacologia , Hiperalgesia/tratamento farmacológico , Hiperalgesia/induzido quimicamente , Antagonistas não Sedativos dos Receptores H1 da Histamina/farmacologia , Antagonistas não Sedativos dos Receptores H1 da Histamina/uso terapêutico , Hipersensibilidade a Drogas/tratamento farmacológico , Camundongos Endogâmicos C57BL
5.
J Cardiothorac Vasc Anesth ; 38(5): 1228-1238, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38453555

RESUMO

OBJECTIVES: Pediatric patients undergoing cardiac surgery usually experience significant surgical pain. Additionally, the effect of poor surgical analgesia creates a pain continuum that extends to the postoperative period. Transversus thoracic muscle plane block (TTMPB) is a novel plane block technique that can provide analgesia to the anterior chest wall. The analgesic role of TTMPB in pediatric cardiac surgery is still uncertain. A meta-analysis was conducted to determine the analgesic efficacy of this procedure. DESIGN AND SETTING: Systematic review and meta-analysis. PubMed, Embase, Web of Science, CENTRAL, WanFang Data, and the China National Knowledge Infrastructure were searched to November 2023, and the Grading of Recommendations Assessment, Development, and Evaluation approach was followed to evaluate the certainty of evidence. PARTICIPANTS: Eligible studies enrolled pediatric patients from 2 months to 12 years old scheduled to undergo cardiac surgery, and randomized them to receive a TTMPB or no block/sham block. MEASUREMENTS AND MAIN RESULTS: Six studies that enrolled 601 pediatric patients were included. Low-certainty evidence from randomized trials showed that, compared with no block or sham block, TTMPB in pediatric patients undergoing cardiac surgery may reduce postoperative modified objective pain score at 12 hours (weighted mean difference [WMD] -2.20, 95% CI -2.73 to -1.68) and 24 hours (WMD -1.76, 95% CI -2.09 to -1.42), intraoperative opioid consumption (WMD -3.83, 95% CI -5.90 to -1.76 µg/kg), postoperative opioid consumption (WMD -2.51, 95% CI -2.84 to -2.18 µg/kg), length of intensive care unit (ICU) stay (WMD -5.56, 95% CI -8.30 to -2.83 hours), and extubation time (WMD -2.13, 95% CI -4.21 to -0.05 hours). Retrospective studies provided very low certainty that the results were consistent with the randomized trials. CONCLUSION: Very low- to low-certainty evidence showed that TTMPB in pediatric patients undergoing cardiac surgery may reduce postoperative pain, opioid consumption, ICU length of stay, and extubation time.


Assuntos
Procedimentos Cirúrgicos Cardíacos , Bloqueio Nervoso , Estudos Observacionais como Assunto , Dor Pós-Operatória , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Dor Pós-Operatória/prevenção & controle , Dor Pós-Operatória/etiologia , Procedimentos Cirúrgicos Cardíacos/métodos , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Bloqueio Nervoso/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Estudos Observacionais como Assunto/métodos , Criança
6.
Ecotoxicol Environ Saf ; 269: 115810, 2024 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-38100849

RESUMO

BACKGROUND: Jujuboside B (JuB) is the main bioactive saponin component of Chinese anti-insomnia herbal medicine Ziziphi Spinosae Semen, which has been reported to possess varied pharmacological functions. Even though it has been traditionally used to treat inflammation- and toxicity-related diseases, the effects of JuB on acetaminophen (APAP) overdose-induced hepatotoxicity have not been determined yet. METHODS: C57BL/6 J mice were pre-treated with JuB (20 or 40 mg/kg) for seven days before APAP (400 mg/kg) injection. After 24 h of APAP treatment, serum, and liver tissues were collected to evaluate the therapeutic effects. To investigate whether the Nrf2-STING signaling pathway is involved in the protective effects of JuB against APAP-induced hepatotoxicity, the mice received the DMXAA (the specific STING agonist) or ML385 (the specific Nrf2 inhibitor) during the administration of JuB, and Hematoxylin-eosin staining, Real-time PCR, immunohistochemical, and western blot were performed. RESULTS: JuB pretreatment reversed APAP-induced CYP2E1 accumulations and alleviated APAP-induced acute liver injury. Furthermore, JuB treatment significantly inhibited oxidative stress and the pro-inflammatory cytokines, as well as alleviated hepatocyte apoptosis induced by APAP. Besides, our result also demonstrated that JuB treatment upregulated the levels of total Nrf2, facilitated its nuclear translocation, upregulated the expression of HO-1 and NQO-1, and inhibited the APAP-induced STING pathway activation. Finally, we verified that the beneficial effects of JuB were weakened by DMXAA and ML385. CONCLUSION: Our study suggested that JuB could ameliorate APAP-induced hepatic damage and verified a previously unrecognized mechanism by which JuB prevented APAP-induced hepatotoxicity through adjusting the Nrf2-STING pathway.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Saponinas , Animais , Camundongos , Acetaminofen/toxicidade , Acetaminofen/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Substâncias Protetoras/farmacologia , Doença Hepática Induzida por Substâncias e Drogas/tratamento farmacológico , Doença Hepática Induzida por Substâncias e Drogas/etiologia , Doença Hepática Induzida por Substâncias e Drogas/prevenção & controle , Camundongos Endogâmicos C57BL , Transdução de Sinais , Estresse Oxidativo , Fígado , Saponinas/farmacologia , Saponinas/uso terapêutico
7.
J Environ Manage ; 356: 120536, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38492421

RESUMO

Due to the continuous degradation (gradual thawing) of permafrost, supra-permafrost water has become an important component of runoff that occurs in cold regions. However, current research has only focused on the amount of water provided by permafrost, and little has been reported regarding the source and formation mechanisms of supra-permafrost water. Due to the difficulty of observation and sampling in cold regions and insufficient data accumulation, model simulations face various difficulties in regard to solving problems related to hydrological processes. Considering the advantages of stable isotope tracer methods in hydrology, the source of supra-permafrost water in Qilian Mountain was analyzed based on 1,840 samples, and the source of supra-permafrost water was determined by end-member mixing analysis (EMMA). Negative line-conditioned excess (lc-excess), lower slope, and particularly the negative intercept of the evaporation line (EL) indicates strong evaporation effects on supra-permafrost water. Remarkably, the evolutionary process, influencing factors, and relationship with other water bodies all indicate that supra-permafrost water is replenished by precipitation, ground ice meltwater, and snow meltwater. The results indicated that from May to October, the contributions of precipitation to the supra-permafrost water were 79%, 83%, 90%, 84%, 87%, and 83%, respectively. Snow meltwater contributed 11%, 13%, 10%, 16%, 11%, and 9%, respectively. Permafrost degradation impacts the water cycle and can increase the minimum monthly runoff and increase groundwater storage. To mitigate the effects of this change, monitoring and early warning systems are essential for detecting signs of permafrost degradation in a timely manner so that appropriate measures can be taken. This may involve the use of remote-sensing technologies, sensor networks, and other methods for real-time monitoring. Establishing mechanisms for sharing information with the relevant departments is crucial. The research results provide scientific and technological support and aid in decision-making to mitigate the negative effects of continuous permafrost degradation in a changing environment.


Assuntos
Água Subterrânea , Pergelissolo , Água , Isótopos , Congelamento
8.
Zhongguo Zhong Yao Za Zhi ; 49(12): 3204-3211, 2024 Jun.
Artigo em Chinês | MEDLINE | ID: mdl-39041081

RESUMO

Ursolic acid has gradually attracted much attention due to its unique pharmacological activities and valuable market value in recent years. Currently, ursolic acid is mostly extracted from loquat leaves, but the plant extraction method has low yield and high cost, and chemical synthesis is not readily available, so the biosynthesis method provides a new source for ursolic acid. α-amyrin acts as the main precursor for the synthesis of ursolic acid, and its yield is positively correlated with ursolic acid yield. Oxidosqualene cyclase(OSC) belongs to a multigene family which can catalyze the common precursor 2,3-oxidosqualene to generate different types of triterpene backbones, and plays a decisive role in the synthesis of triterpenoids. However, there are fewer reported key genes catalyzing the synthesis of α-amyrin in medicinal plants, and the yield and proportion of α-amyrin in the catalyzed products have always been a focus of research. In this study, ItOSC2, MdOSC1, AaOSC2 and CrAS, four enzymes capable of catalyzing the production of α-amyrin from 2,3-oxidosqualene, were cloned from Iris tectorum, Malus domestica, Artemisia annua and Catharanthus roseus, subject to sequence alignment and phylogenetic tree analyses, and transformed into Saccharomyces cerevisiae as plasmids. After 7 days of fermentation, the yield and proportions of α-amyrin, ß-amyrin and ergosterol were measured. Finally, AaOSC2 with the best ability to catalyze the generation of α-amyrin was filtered out, providing a key gene element for the later construction of engineered yeast strains with high production of α-amyrin and ursolic acid.


Assuntos
Transferases Intramoleculares , Ácido Oleanólico , Transferases Intramoleculares/genética , Transferases Intramoleculares/metabolismo , Ácido Oleanólico/análogos & derivados , Ácido Oleanólico/metabolismo , Ácido Oleanólico/química , Ácido Oleanólico/biossíntese , Clonagem Molecular , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Triterpenos/metabolismo , Triterpenos/química , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/enzimologia , Saccharomyces cerevisiae/metabolismo , Filogenia , Triterpenos Pentacíclicos
9.
Zhongguo Zhong Yao Za Zhi ; 49(4): 902-911, 2024 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-38621897

RESUMO

Alzheimer's disease(AD), vascular dementia(VD), and traumatic brain injury(TBI) are more common cognitive impairment diseases characterized by high disability and mortality rates, imposing a heavy burden on individuals and their families. Although AD, VD, and TBI have different specific mechanisms, their pathogenesis is closely related to the nucleotide-binding oligome-rization domain-like receptor protein 3(NLRP3). The NLRP3 inflammasome is involved in neuroinflammatory responses, mediating microglial polarization, regulating the reduction of amyloid ß-protein(Aß) deposition, neurofibrillary tangles(NFTs) formation, autophagy regulation, and maintaining brain homeostasis, and synaptic stability, thereby contributing to the development of AD, VD, and TBI. Previous studies have shown that traditional Chinese medicine(TCM) can alleviate neuroinflammation, promote microglial polarization towards the M2 phenotype, reduce Aß deposition and NFTs formation, regulate autophagy, and maintain brain homeostasis by intervening in NLRP3 inflammasome, hence exerting a role in preventing and treating cognitive impairment-related diseases, reducing psychological and economic pressure on patients, and improving their quality of life. Therefore, this article elucidated the role of NLRP3 inflammasome in AD, VS, and TBI, and provided a detailed summary of the latest research results on TCM intervention in NLRP3 inflammasome for the prevention and treatment of these diseases, aiming to inherit the essence of TCM and provide references and foundations for clinical prevention and treatment of cognitive impairment-related diseases with TCM. Meanwhile, this also offers insights and directions for further research in TCM for the prevention and treatment of cognitive impairment-related diseases.


Assuntos
Doença de Alzheimer , Disfunção Cognitiva , Humanos , Inflamassomos/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Peptídeos beta-Amiloides/metabolismo , Medicina Tradicional Chinesa , Qualidade de Vida , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/prevenção & controle , Disfunção Cognitiva/tratamento farmacológico , Disfunção Cognitiva/prevenção & controle
10.
Biomed Chromatogr ; 37(2): e5533, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36264680

RESUMO

A simple and sensitive method using in vivo microdialysis coupled with UPLC-MS/MS was established to evaluate the pharmacokinetics of Shuang Hu tincture (SHZTN). Xevo TQ-S was used to analyze the active ingredients of mesaconitine, hypaconitine, 4-hydroxycinnamic acid, ferulic acid and N-(2, 3-dimethyl phenyl)-2- aminobenzoic acid of SHZTN. Samples were prepared using a methanol precipitation method and the internal standards lannaconitine and p-hydroxybenzoic acid were added. The method validation was conducted according to the guidelines of the Pharmacopoeia of China. A good linear range was obtained in the range of 1-2,000 ng/ml. The intra-day and inter-day precisions were less than 14.7%, and the accuracy range of all the analytes was -10.5-9.3%. The recovery of each analyte was over 95.5%, and matrix effects can be neglected. After a single dose of 20 mg/kg SHZTN, the area under the curve and peak concentration of the five active ingredients were significantly increased by transdermal compared with oral administration, which indicated the high bioavailability of SHZTN. The time to peak concentration of all compounds was <3.4 h, and the half-life was <15.4 h, which indicated that the five compounds have the best absorption and rapid elimination. The method was successfully developed and applied to the pharmacokinetic study of SHZTN.


Assuntos
Medicamentos de Ervas Chinesas , Espectrometria de Massas em Tandem , Ratos , Animais , Espectrometria de Massas em Tandem/métodos , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia Líquida , Medicamentos de Ervas Chinesas/farmacocinética , Administração Oral , Reprodutibilidade dos Testes
11.
J Environ Manage ; 342: 118198, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37270977

RESUMO

Drastic changes in the cryosphere have a significant impact on the quantity and formation process of water resources in the Qilian Mountains. The present study focused on quantitative evaluation of runoff components and runoff formation processes during strong ablation periods (August), in 2018, 2020, and 2021, in the transition zone between endorheic and exorheic basins in China, based on 1906 stable isotope samples. The results revealed that as the altitude decreased, the contribution of glacier and snow meltwater and permafrost water to runoff decreased, whereas that of the precipitation increased. Precipitation is a major source of river runoff in the Qilian Mountains. Notably, the runoff yield and concentration of rivers that were greatly affected by the cryosphere exhibited the following characteristics: (1) The altitude effect of stable isotopes was not significant and even showed a reverse trend in some rivers. (2) The processes of runoff yield and composition were relatively slow; as such, precipitation, glacier and snow meltwater, and supra-permafrost water were first transformed into groundwater and then supplied runoff to upstream mountainous region. (3) Finally, stable isotope composition in such rivers were similar to those in glaciers and snow meltwater, with small fluctuations. Therefore, the water sources of rivers affected by the cryosphere are more uncertain than those of rivers unaffected by the cryosphere. In future study, a prediction model of extreme precipitation and hydrological events will be developed, and a prediction technology for runoff formation and evolution in glacier snow and permafrost will be developed to integrate short-and long-term forecasts.


Assuntos
Água Subterrânea , Isótopos , Recursos Hídricos , Neve , Rios , Água , Monitoramento Ambiental/métodos
12.
Water Sci Technol ; 87(9): 2128-2141, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37186619

RESUMO

Falling film evaporation technology is widely used in the treatment of salt-containing wastewater in coal chemical industry. However, there is still a lack of research on the inlet method of vertical falling film evaporation tubes. In this paper, the heat and mass transfer processes of saline wastewater under vertical and tangential inlets were investigated using numerical simulations. On this basis, the differences in flow and heat transfer processes between saline wastewater and pure water under tangential inlet were investigated. The results showed that the flow velocity of saline wastewater with a falling film evaporation tube in a tangential inlet mode was larger. Meanwhile, the turbulence in this way was more intense and the fluid temperature in the vertical tube was higher. Saline wastewater has higher temperature and smaller liquid volume fraction than pure water liquid membrane in the range of 193-1,000 mm from the inlet. The use of tangential inlet method to treat salt-containing wastewater has higher evaporation efficiency and is a very effective way to guide the improvement of heat transfer efficiency.


Assuntos
Temperatura Alta , Águas Residuárias , Baías , Temperatura
13.
Zhonghua Nan Ke Xue ; 29(10): 881-887, 2023 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-38639656

RESUMO

OBJECTIVE: Exploring the effects and mechanisms of long non coding RNA (lncRNA) RPL22P1-201 on prostate cancer cell proliferation, cell cycle, and docetaxel sensitivity by regulating miR-216b-5p expression. METHODS: The Cancer LncRNA Census database was used to analyze the differential expression of RPL22P1-201 between prostate cancer tissue and normal tissue. Real time quantitative polymerase chain reaction (qRT-PCR) was used to detect the expression level of RPL22P1-201 in prostate cancer cell lines (DU-145, C4-2B, PC3, 22Rv1, LNCaP) and normal prostate epithelial cells (RWPE-1). PC3 cells were divided into si-RPL22P1-201 group (transfected with RPL22P1-201 interference sequence) and si-NC group (transfected with si-NC sequence). Colony formation assay was used to detect the proliferation ability of PC3 cells. Flow cytometry was used to detect the PC3 cell cycle. The CCK-8 method was used to detect the proliferation of PC3 cells in each group after treatment with docetaxel. The dual luciferase reporter gene experiment verifies the binding of RPL22P1-201 to the target gene. qRT-PCR was used to detect the expression level of miR-216b-5p. Western blot was used to detect the expression levels of TrkB, CDK4, cyclin D2, cyclin D3, and CDK6 proteins. RESULTS: The expression level of RPL22P1-201 in prostate cancer tissue was higher than that in normal tissue (P<0.01). The expression level of RPL22P1-201 in prostate cancer cell lines was higher than that in normal prostate epithelial cells (P<0.01). The number of colonies in the si-NC group and si-RPL22P1-201 group was (256.1 ± 28.79) and (78.77 ± 14.52), respectively. The difference was statistically significant (P<0.01). The G0/G1 cell rates in the si-NC group and si-RPL22P1-201 group were (43.18 ± 4.56)% and (68.85 ± 3.40)%, respectively. The S cell rates were (36.84 ± 2.28)% and (24.27 ± 2.74)%, respectively. The G2/M cell rates were (19.98 ± 2.69)% and (6.88 ± 1.57)%, respectively, and the differences were statistically significant (all P<0.05). The cell survival rate of the si-RPL22P1-201 group under the action of docetaxel was lower than that of the si-NC group (all P<0.05). RPL22P1-201 can pair and bind with miR-216b-5p (P<0.01). Compared with the si-NC group, the si-RPL22P1-201 group showed a decrease in miR-216b-5p expression in PC3 cells (P<0.01), and a decrease in TrkB, CDK4, cyclin D2, cyclin D3, and CDK6 protein expression. CONCLUSIONS: RPL22P1-201 is highly expressed in prostate cancer, and silencing RPL22P1-201 inhibits prostate cancer PC3 cell proliferation and cell cycle by increasing miR-216b-5p expression, and enhances PC3 cell sensitivity to docetaxel.


Assuntos
MicroRNAs , Neoplasias da Próstata , RNA Longo não Codificante , Humanos , Masculino , Apoptose/genética , Ciclo Celular , Linhagem Celular Tumoral , Proliferação de Células , Ciclina D2/genética , Ciclina D2/metabolismo , Ciclina D3/genética , Ciclina D3/metabolismo , Docetaxel/farmacologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias da Próstata/genética , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo
14.
Zhonghua Nan Ke Xue ; 29(4): 311-316, 2023 Apr.
Artigo em Chinês | MEDLINE | ID: mdl-38598214

RESUMO

OBJECTIVE: To investigate the correlation of serum and seminal plasma homocysteine (Hcy) levels with semen parameters in men and its effect on recurrent spontaneous abortion (RSA) in their spouses. METHODS: The study included 103 males subjects undergoing preconception examination in the reproduction center from March 2022 to June 2023. According to whether their spouses had a history of RSA or not, we divided their subjects into an RSA (n = 43) and a non-RSA group (NRSA, n = 60), obtained their serum and seminal plasma Hcy levels and semen parameters, and analyzed their correlation. RESULTS: The serum Hcy level was significantly correlated with the sperm DNA fragmentation index (DFI) (r = 0.316, P = 0.005), but not with the seminal plasma Hcy level (r = -0.041, P = 0.723) and other semen parameters of the subjects (P > 0.05). There was no significant correlation between seminal plasma Hcy and semen parameters (P > 0.05). The median serum Hcy was significantly higher in the RSA than in the NRSA group (18.39 ï¼»13.02, 42.84ï¼½ vs 14.65 ï¼»12.00, 18.20ï¼½ µmol/L), with statistically significant difference in the overall distribution of serum Hcy between the two groups (Z=-2.20, P = 0.028), so was the median sperm DFI in the former than in the latter group (25.00% ï¼»12.50%, 37.25%ï¼½ vs 13.00% ï¼»11.00%, 18.50%ï¼½), with statistically significant difference in the overall sperm DFI distribution between the two groups (Z=-2.74, P = 0.006). CONCLUSION: The serum Hcy level was positively correlated with sperm DFI, and both serum Hcy and sperm DFI were significantly elevated in men with spousal RSA, which is expected to be used as a clinical screening indicator for males with spousal RSA.


Assuntos
Aborto Habitual , Líquidos Corporais , Feminino , Gravidez , Masculino , Humanos , Sêmen , Espermatozoides
15.
Angew Chem Int Ed Engl ; 62(13): e202218717, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36728627

RESUMO

The aqueous electrocatalytic reduction of NO3 - into NH3 (NitrRR) presents a sustainable route applicable to NH3 production and potentially energy storage. However, the NitrRR involves a directly eight-electron transfer process generally required a large overpotential (<-0.2 V versus reversible hydrogen electrode (vs. RHE)) to reach optimal efficiency. Here, inspired by biological nitrate respiration, the NitrRR was separated into two stages along a [2+6]-electron pathway to alleviate the kinetic barrier. The system employed a Cu nanowire catalyst produces NO2 - and NH3 with current efficiencies of 91.5 % and 100 %, respectively at lower overpotentials (>+0.1 vs. RHE). The high efficiency for such a reduction process was further explored in a zinc-nitrate battery. This battery could be specified by a high output voltage of 0.70 V, an average energy density of 566.7 Wh L-1 at 10 mA cm-2 and a power density of 14.1 mW cm-2 , which is well beyond all previously reported similar concepts.

16.
Biophys J ; 121(23): 4666-4678, 2022 12 06.
Artigo em Inglês | MEDLINE | ID: mdl-36271623

RESUMO

Double-layered channels of sinusoid lumen and Disse space separated by fenestrated liver sinusoidal endothelial cells (LSECs) endow the unique mechanical environment of the liver sinusoid network, which further guarantees its biological function. It is also known that this mechanical environment changes dramatically under liver fibrosis and cirrhosis, including the reduced plasma penetration and metabolite exchange between the two flow channels and the reduced Disse space deformability. The squeezing of leukocytes through narrow sinusoid lumen also affects the mechanical environment of liver sinusoid. To date, the detailed flow-field profile of liver sinusoid is still far from clear due to experimental limitations. It also remains elusive whether and how the varied physical properties of the pathological liver sinusoid regulate the fluid flow characteristics. Here a numerical model based on the immersed boundary method was established, and the effects of Disse space and leukocyte elasticities, endothelium permeability, and sinusoidal stenosis degree on fluid flow as well as leukocyte trafficking were specified upon a mimic liver sinusoid structure. Results showed that endothelium permeability dominantly controlled the plasma penetration velocity across the endothelium, whereas leukocyte squeezing promoted local penetration and significantly regulated wall shear stress on hepatocytes, which was strongly related to the Disse space and leukocyte deformability. Permeability and elasticity cooperatively regulated the process of leukocytes trafficking through the liver sinusoid, especially for stiffer leukocytes. This study will offer new insights into deeper understanding of the elaborate mechanical features of liver sinusoid and corresponding biological function.


Assuntos
Células Endoteliais , Leucócitos , Fígado
17.
J Synchrotron Radiat ; 29(Pt 3): 775-786, 2022 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-35511010

RESUMO

The structure and mechanical properties of the stomatopod dactyl club have been studied extensively for its extreme impact tolerance, but a systematic in situ investigation on the multiscale mechanical responses under high-speed impact has not been reported. Here the full dynamic deformation and crack evolution process within projectile-impacted dactyl using combined fast 2D X-ray imaging and high-resolution ex situ tomography are revealed. The results show that hydration states can lead to significantly different toughening mechanisms inside dactyl under dynamic loading. A previously unreported 3D interlocking structural design in the impact surface and impact region is reported using nano X-ray tomography. Experimental results and dynamic finite-element modeling suggest this unique structure plays an important role in resisting catastrophic structural damage and hindering crack propagation. This work is a contribution to understanding the key toughening strategies of biological materials and provides valuable information for biomimetic manufacturing of impact-resistant materials in general.


Assuntos
Crustáceos , Casco e Garras , Tomografia Computadorizada por Raios X , Animais , Fenômenos Biomecânicos , Crustáceos/anatomia & histologia , Crustáceos/fisiologia , Casco e Garras/anatomia & histologia , Casco e Garras/diagnóstico por imagem , Casco e Garras/fisiologia , Fenômenos Mecânicos , Estresse Mecânico
18.
Cytokine ; 159: 156017, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36054963

RESUMO

BACKGROUND: Small-for-size syndrome following liver surgery is characterized by compromised liver regeneration. Liver macrophages play key roles in initiating liver regeneration, and modulation of the immune microenvironment through macrophages may accelerate liver regeneration. In our current study, we aimed to explore the involvement of innate immunity after extended hepatectomy in rats and humans, and to test the effect of immunity modulation on small-for-size liver regeneration in rats. METHODS: Serum programmed cell death protein ligand 1 (PD-L1) was measured after major hepatectomy and minor hepatectomy in humans and rats. Liver regeneration in rats was assessed using liver-to-body weight ratio and kinetic growth rate, antigen Ki67 and proliferating cell nuclear antigen (PCNA), and macrophage polarization was assessed by inducible nitric oxide synthase (iNOS), cluster of differentiation protein 163 (CD163) expression by immunohistochemistry (IHC) and iNOS/CD163 ratio. Rat hepatocyte BRL or human hepatocyte LO2 were co-cultured with rat bone marrow-derived macrophages or human macrophages THP-1. BMS-1 or Nivolumab were used to block programmed cell death protein 1 (PD-1)/PD-L1 in vitro and in vivo. RESULTS: PD-L1 expressions were significantly higher following major hepatectomy compared to minor resection in both humans and rats; compromised liver regeneration after extended hepatectomy in rats was associated with PD-L1 upregulation and M2 macrophage polarization. M1 macrophages increased proliferation of hepatocytes through interleukin-6 (IL-6), and M2 macrophages decreased hepatocyte proliferation; blocking PD-1/PD-L1 reversed the effect of M2 macrophages on the survival of hepatocytes in vitro and promoted liver growth in rats through M1 macrophage polarization. CONCLUSION: Compromised hepatic regeneration following extended hepatectomy is characterized by M2 macrophage polarization and upregulated PD-L1 expression. Blocking PD-1/PD-L1 may enhance small-for-size liver regeneration by inducing M1 macrophage polarization.


Assuntos
Hepatectomia , Hepatopatias , Animais , Proteínas Reguladoras de Apoptose/metabolismo , Antígeno B7-H1/metabolismo , Humanos , Interleucina-6/metabolismo , Antígeno Ki-67/metabolismo , Ligantes , Óxido Nítrico Sintase Tipo II/metabolismo , Nivolumabe/metabolismo , Receptor de Morte Celular Programada 1 , Antígeno Nuclear de Célula em Proliferação/metabolismo , Ratos
19.
Arch Microbiol ; 204(6): 338, 2022 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35590019

RESUMO

A Gram-stain-negative, strictly aerobic, non-flagellated, oxidase- and catalase-positive, rod-shaped marine bacterium, designated strain DM8T, was isolated from the intestine of Trichiurus japonicus in Weihai, China. The strain optimally grew at 25-35℃, with 1.0-4.0% (w/v) NaCl and at pH 7.0-8.0. Its colonies were circular, slightly yellow, non-transparent, smooth, and approximately 0.8-1.5 mm in diameter, after being cultured for 48 h on marine agar 2216. Based on the result of phylogenetic analysis of 16S rRNA gene sequence, strain DM8T had close relationship with Oceanisphaera profunda SM1222T (96.9%) and the type strain DSM 15406 T of the type species Oceanisphaera litoralis (94.7%), respectively. Genome sequencing revealed a genome size of 3,109,059 bp and a G + C content of 46.9 mol%. It had Q-8 as the sole respiratory quinone and possessed C16:0, summed features 3 (C16:1ω7c/C16:1ω6c) and summed features 8 (C18:1ω7c/C18:1ω6c) as major fatty acids. The major polar lipid profile was composed of phosphatidylglycerol and phosphatidylethanolamine. Based on the phenotypic, chemotaxonomic characterizations, phylogenetic properties and genome analysis, strain DM8T should represent a novel species of the genus Oceanisphaera, for which the name Oceanisphaera pacifica sp. nov. is proposed. The type strain is DM8T (= KCTC 82764 T = MCCC 1K06133T).


Assuntos
Perciformes , Água do Mar , Animais , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/química , Intestinos , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Água do Mar/microbiologia , Análise de Sequência de DNA , Ubiquinona/química
20.
Arch Microbiol ; 204(9): 586, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36048288

RESUMO

Members of the genus Marinomonas are known for their environmental adaptation and metabolically versatility, with abundant proteins associated with antifreeze, osmotic pressure resistance, carbohydrase and multiple secondary metabolites. Comparative genomic analysis focusing on secondary metabolites and orthologue proteins was conducted with 30 reference genome sequences in the genus Marinomonas. In this study, a Gram-stain-negative, rod-shaped, non-flagellated and strictly aerobic bacterium, designated as strain E8T, was isolated from the red algae (Gelidium amansii) in the coastal of Weihai, China. Optimal growth of the strain E8T was observed at temperatures 25-30 °C, pH 6.5-8.0 and 1-3% (w/v) NaCl. The DNA G + C content was 42.8 mol%. The predominant isoprenoid quinone was Q-8 and the major fatty acids were C16:0, summed feature 3 and summed feature 8. The major polar lipids were phosphatidylglycerol (PG) and phosphatidylethanolamine (PE). Based on data obtained from this polyphasic taxonomic study, strain E8T should be considered as a novel species of the genus Marinomonas, for which the name Marinomonas algarum is proposed. The type strain is E8T (= KCTC 92201T = MCCC 1K07070T).


Assuntos
Marinomonas , Rodófitas , Técnicas de Tipagem Bacteriana , DNA Bacteriano/genética , Ácidos Graxos/química , Genômica , Marinomonas/genética , Fosfolipídeos/química , Filogenia , RNA Ribossômico 16S/genética , Rodófitas/genética , Rodófitas/microbiologia , Análise de Sequência de DNA , Ubiquinona/química
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