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1.
Bioorg Chem ; 138: 106649, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37307715

RESUMO

The Hedgehog/Glioma-associated oncogene (Hh/Gli) signaling pathway plays an essential role in embryonic development and tissue homeostasis. Aberrant regulation of this pathway has been linked to various human malignancies. Gli1, the downstream transcription factor of the Hh pathway, is the ultimate effector of the canonical Hh pathway and has been identified as a common regulator of several tumorigenic pathways prevalent in Hh-independent cancers. Thus Gli1 represents a unique and promising drug target for a wide range of cancers. However, the identification and development of small molecules that directly target Gli1 protein have progressed slowly, due to an insufficient efficacy and selectivity. Herein, we developed novel small-molecule Gli1 degraders based on the hydrophobic tagging (HyT) strategy. The Gli1 HyT degrader 8e potently inhibited the proliferation of Gli1-overexpressed HT29 colorectal cancer cells, induced Gli1 degradation with a DC50 value of 5.4 µM in HT29 and achieved 70% degradation at 7.5 µM in MEFPTCH1-/- and MEFSUFU-/-cell lines, via proteasome pathway. Compared to the canonical Hh antagonist Vismodegib, 8e exhibited much stronger potency in suppressing the mRNA expression of Hh target genes in Hh-overactivated MEFPTCH1-/- and Vismodegib resistant MEFSUFU-/- cells. Our study provides small molecule Gli1 degraders effectively interfering with both canonical and noncanonical Hh signaling and overcoming current Smoothened (SMO) antagonists resistance, which might pave a new avenue for developing therapeutic modalities targeting Hh/Gli1 signaling pathway.


Assuntos
Antineoplásicos , Neoplasias Cutâneas , Humanos , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Proteína GLI1 em Dedos de Zinco/genética , Proteína GLI1 em Dedos de Zinco/metabolismo , Transdução de Sinais , Antineoplásicos/farmacologia
2.
Eur J Med Chem ; 251: 115267, 2023 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-36933395

RESUMO

GPR40 is primarily expressed in pancreatic islet ß-cells, and its activation by endogenous ligands of medium to long-chain free fatty acids or synthetic agonists is clinically proved to improve glycemic control by stimulating glucose-dependent insulin secretion. However, most of the reported agonists are highly lipophilic, which might cause lipotoxicity and the off-target effects in CNS. Particularly, the withdrawal of TAK-875 from clinical trials phase III due to liver toxicity concern threw doubt over the long-term safety of targeting GPR40. Improving the efficacy and the selectivity, thus enlarging the therapeutic window would provide an alternative to develop safe GPR40-targeted therapeutics. Herein, by employing an innovative "three-in-one" pharmacophore drug design strategy, the optimal structural features for GPR40 agonist was integrated into one functional group of sulfoxide, which was incorporated into the ß-position of the propanoic acid core pharmacophore. As a result, the conformational constraint, polarity as well as chirality endowed by the sulfoxide significantly enhanced the efficacy, selectivity and ADMET properties of the novel (S)- 2-(phenylsulfinyl)acetic acid-based GPR40 agonists. The lead compounds (S)-4a and (S)-4s exhibited robust plasma glucose-lowering effects and insulinotropic action during an oral glucose tolerance test in C57/BL6 mice, excellent pharmacokinetic profile and little hepatobiliary transporter inhibition, marginal cell toxicities against human primary hepatocyte at 100 µM.


Assuntos
Insulina , Receptores Acoplados a Proteínas G , Animais , Humanos , Camundongos , Ácidos Carboxílicos/farmacologia , Ácidos Graxos , Glucose , Teste de Tolerância a Glucose , Hipoglicemiantes/química
3.
Chinese Journal of Hepatology ; (12): 422-427, 2023.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-986146

RESUMO

Objective: T lymphocyte exhaustion is an important component of immune dysfunction. Therefore, exploring peripheral blood-exhausted T lymphocyte features in patients with hepatitis B virus-related acute-on-chronic liver failure may provide potential therapeutic target molecules for ACLF immune dysfunction. Methods: Six cases with HBV-ACLF and three healthy controls were selected for T-cell heterogeneity detection using the single-cell RNA sequencing method. In addition, exhausted T lymphocyte subpopulations were screened to analyze their gene expression features, and their developmental trajectories quasi-timing. An independent sample t-test was used to compare the samples between the two groups. Results: Peripheral blood T lymphocytes in HBV-ACLF patients had different differentiation trajectories with different features distinct into eight subpopulations. Among them, the CD4(+)TIGIT(+) subsets (P = 0.007) and CD8(+)LAG3(+) (P = 0.010) subsets with highly exhausted genes were significantly higher than those in healthy controls. Quasi-time analysis showed that CD4(+)TIGIT(+) and CD8(+)LAG3(+) subsets appeared in the late stage of T lymphocyte differentiation, suggesting the transition of T lymphocyte from naïve-effector-exhausted during ACLF pathogenesis. Conclusion: There is heterogeneity in peripheral blood T lymphocyte differentiation in patients with HBV-ACLF, and the number of exhausted T cells featured by CD4(+)TIGIT(+)T cell and CD8(+)LAG3(+) T cell subsets increases significantly, suggesting that T lymphocyte immune exhaustion is involved in the immune dysfunction of HBV-ACLF, thereby identifying potential effective target molecules for improving ACLF patients' immune function.


Assuntos
Humanos , Vírus da Hepatite B , Insuficiência Hepática Crônica Agudizada/patologia , Hepatite B Crônica , Subpopulações de Linfócitos T/patologia , Receptores Imunológicos
4.
Chem Commun (Camb) ; 58(97): 13447-13450, 2022 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-36350039

RESUMO

A concise synthesis of the tetrahydropyranyl side chain of verucopeptin, an antitumor antibiotic cyclodepsipeptide efficacious against MDR cancers in vivo, is achieved using 12 steps in the longest linear sequence and 21 total steps, in which Julia-Kocienski olefination for the segments coupling, asymmetric hydroxylation as well as stereoselective synthesis of stable tetrahydropyran ring from a D-isoascorbic acid derivative are key steps. This convergent synthetic strategy enables the structural modification and mechanism study of verucopeptin for its clinical applications.


Assuntos
Resistência a Múltiplos Medicamentos , Neoplasias , Humanos , Resistencia a Medicamentos Antineoplásicos , Antibacterianos/farmacologia
5.
Nat Prod Res ; : 1-9, 2022 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-35959693

RESUMO

Two new natural products named 5,7-dihydroxy-3,3',6,8-tetramethoxy-4',5'-methylenedioxyflavone (1) and 3,3',5,7-tetramethoxy-4',5'-methylenedioxyflavone (2), along with thirteen known compounds, ß-sitosterol (3), desmethoxyyangonin (4), hexadecane (5), 3,9-bis(2,4-di-tert-butylphenoxy)-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane 3,9-dioxide (6), 2'6'-dihydroxy-4'-methoxydihydrochalcone (7), cardamonin (8), 3,3',5,6,7,8-hexamethoxy-4',5'-methylenedioxyflavone (9), isofraxidin (10), aniba dimer A (11), 3,3',4',5,5',8-hexamethoxy-6,7-methylenedioxyflavone (12), quercetin (13), quercitrin (14) and isoquercitrin (15) were isolated from Sarcandra glabra (Thunb.) Nakai by various chromatographic methods. Compounds 1, 2, 4, 6, 11, and 12 were isolated from S. glabra for the first time. Their chemical structures were identified through the analysis of NMR and HR-MS spectra. The anti-inflammatory and cytotoxic activities of compounds 1-15 were evaluated in cell assays. The results indicated that compounds 1, 7, 8, 10, 14, and 15 significantly inhibited the NO production in LPS-induced RAW 264.7 murine macrophage cells. Moreover, compounds 1, 3, 4, 7, 8, 9, 10 and 12 exhibited a cytotoxic effect on the human HepG2 cell line.

6.
Chem Commun (Camb) ; 58(60): 8340-8343, 2022 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-35758629

RESUMO

An unexpected iodine(III)-mediated C(sp3)-C(sp2) bond cleavage of 3-(methylamino)-2-(2-substitutedbenzoyl)acrylates for efficient synthesis of privileged scaffold 4-quinolones was described. Notably, a wide range of alkyl groups (e.g. methyl, tert-butyl or alkyl chain) can be conveniently cleaved in this system. The detailed mechanism studies revealed that the transformation proceeded through cascade ipso-cyclization and 1,2-carbonyl migration, the smaller bond energy determined ortho C-C bond cleavage rather than C-H bond cleavage, via an enamine radical intermediate.


Assuntos
Iodo , Quinolonas , Ciclização , Iodetos , Iodo/química , Metais
7.
Eur J Pharmacol ; 925: 174996, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35513018

RESUMO

In this work, we examined whether baicalin (BC), a bioactive flavonoid in Scutellaria baicalensis Georgi, can reduce high-fat diet (HFD)-induced metabolic syndrome (MetS) in mice. The UPLC-QTOF/MS was used for metabolome profiles analysis, and an analysis of bacterial 16S rDNA in feces was used to examine the effects of BC on gut microbiota composition. Our results showed that BC (400 mg/kg) could reduce the body weight gain, decrease hepatic fat accumulation and abnormal blood lipids, and increase insulin sensitivity after 8 weeks of treatment. BC could reverse the alteration of 7 metabolites induced by HFD and the metabolic pathways responsive to BC intervention including citrate cycle, alanine, aspartate and glutamate metabolism, glycerophospholipid metabolism, and aminoacyl-tRNA biosynthesis. 16S rDNA analysis demonstrated that BC altered the composition and function of gut microbiota in MetS mice. Notably, we found that the change in succinic acid was negatively associated with the changes in Bacteroides and Sutterella, and positively associated with the change in Mucispirillum. Moreover, we confirmed that succinic acid displayed a metabolic protective effect on MetS mice. The antibiotic treatment verified that BC exerts metabolic protection through gut microbiota. Our findings suggested BC may be a potential therapeutic drug to ameliorate diet induced MetS and gut microbiome may be a novel mechanistic target of BC for treatment of MetS.


Assuntos
Microbioma Gastrointestinal , Síndrome Metabólica , Animais , DNA Ribossômico/farmacologia , Dieta Hiperlipídica/efeitos adversos , Flavonoides/farmacologia , Flavonoides/uso terapêutico , Síndrome Metabólica/tratamento farmacológico , Síndrome Metabólica/etiologia , Camundongos , Camundongos Endogâmicos C57BL , Ácido Succínico/farmacologia
8.
RSC Med Chem ; 13(3): 246-257, 2022 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-35434626

RESUMO

Src homology 2 domain-containing protein tyrosine phosphatase (SHP2) is a non-receptor protein tyrosine phosphatase encoded by the Ptpn11 gene, which regulates cell growth, differentiation and apoptosis via modulating various signaling pathways, such as the RAS/ERK signaling pathway, and participates in the PD-1/PD-L1 pathway governing immune surveillance. It has been recognized as a breakthrough antitumor therapeutic target. Besides, numerous studies have shown that SHP2 plays an important role in the regulation of inflammatory diseases. However, inhibitors targeting the active site of SHP2 lack drug-likeness due to their low selectivity and poor bioavailability, thus none has advanced to clinical development. Recently, allosteric inhibitors that stabilize the inactive conformation of SHP2 have achieved breakthrough progress, providing the clinical proof for the druggability of SHP2 as an antitumor drug target. This paper reviews the recently reported design and discovery of SHP2 small molecule inhibitors, focused on the structure-activity relationship (SAR) analysis of several representative SHP2 inhibitors, outlining the evolution and therapeutic potential of the small molecule inhibitors targeting SHP2.

9.
J Med Chem ; 65(1): 333-342, 2022 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-34963283

RESUMO

Although a myriad of bioorthogonal prodrugs have been developed, very few of them present both fast reaction kinetics and complete cleavage. Herein, we report a new bioorthogonal prodrug strategy with both fast reaction kinetics (k2: ∼103 M-1 s-1) and complete cleavage (>90% within minutes) using the bioorthogonal reaction pair of N-oxide and boron reagent. Distinctively, an innovative 1,6-elimination-based self-immolative linker is masked by N-oxide, which can be bioorthogonally demasked by a boron reagent for the release of both amino and hydroxy-containing payload in live cells. Such a strategy was applied to prepare a bioorthogonal prodrug for a camptothecin derivative, SN-38, resulting in 10-fold weakened cytotoxicity against A549 cells, 300-fold enhanced water solubility, and "on-demand" activation upon a click reaction both in vitro and in vivo. This novel bioorthogonal prodrug strategy presents significant advances over the existing ones and may find wide applications in drug delivery in the future.


Assuntos
Compostos de Boro/química , Liberação Controlada de Fármacos , Irinotecano/farmacologia , Neoplasias Pulmonares/tratamento farmacológico , Nanopartículas/administração & dosagem , Inibidores da Topoisomerase I/farmacologia , Animais , Apoptose , Proliferação de Células , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Irinotecano/química , Cinética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Camundongos , Camundongos Nus , Nanopartículas/química , Inibidores da Topoisomerase I/química , Células Tumorais Cultivadas , Ensaios Antitumorais Modelo de Xenoenxerto
11.
Can J Microbiol ; 68(3): 215-226, 2022 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34855458

RESUMO

Vibrio harveyi can cause infections and diseases in a variety of marine vertebrates and invertebrates, which are harmful to the aquaculture industry. The LuxS quorum-sensing system regulates the expression of virulence factors in a wide variety of pathogenic bacteria. In this study, an in-frame deletion of the luxS gene was constructed to reveal the role of LuxS in the physiology and virulence of V. harveyi. Statistical analysis showed no significant differences in the growth ability, biofilm formation, antibiotic susceptibility, virulence by intraperitoneal injection, and ability of V. harveyi to colonize the spleen and liver of the pearl gentian grouper between the wild-type (WT) and luxS mutant. However, deletion of luxS decreased the secretion of extracellular protease, while increasing swimming and swarming abilities. Simultaneously, a luxS-deleted mutant showed overproduction of lateral flagella, and an intact luxS complemented this defect. Since motility is flagella dependent, 16 V. harveyi flagella biogenesis related genes were selected for further analysis. Based on quantitative real-time reverse transcription-PCR (qRT-PCR), the expression levels of these genes, including the polar flagella genes flaB, flhA, flhF, flhB, flhF, fliS, and flrA and the lateral flagella genes flgA, flgB, fliE, fliF, lafA, lafK, and motY, were significantly upregulated in the ΔluxS: pMMB207 (ΔluxS+) strain as compared with the V. harveyi 345: pMMB207 (WT+) and C-ΔluxS strains during the early, mid-exponential, and stationary growth phases. Our results indicate that LuxS plays an important role in controlling motility, flagella biogenesis, and extracellular protease secretion in V. harveyi.


Assuntos
Peptídeo Hidrolases , Vibrio , Animais , Proteínas de Bactérias/metabolismo , Liases de Carbono-Enxofre/metabolismo , Regulação Bacteriana da Expressão Gênica , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Vibrio/genética
12.
Chinese Journal of Hepatology ; (12): 57-62, 2022.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-935908

RESUMO

Objective: To evaluate the incidence of immune checkpoint inhibitor-based combination therapy-induced liver damage in patients with primary liver cancer. Methods: Clinical data of 65 hospitalized cases of primary liver cancer treated with programmed cell death-1 its ligand programmed death-ligand 1 (PD-1/PD-L1) antibody in the Department of Infectious Diseases of the Second Affiliated Hospital of Chongqing Medical University from January 1, 2018 to March 31, 2021 were retrospectively analyzed. The degree of liver injury before and after treatment was assessed according to CTCAE v5.0. Patients were grouped according to gender, age, presence or absence of cirrhosis, baseline Child-Pugh score, BCLC stage, and treatment regimen to compare the incidence of liver injury under different conditions. The χ (2) test or rank-sum test was used for comparison among multiple groups. Results: 46 cases (70.77%) had liver damage of any grade according to the CTCAE V5.0 criteria during the treatment and observation period. All 6 cases who received standardized anti-hepatitis B virus (HBV) treatment developed liver damage. 10 (15.38%), 15 (23.08%), 19 (29.23%), and 2 (3.08%) cases had grade 1, 2, 3, and 4 liver damage respectively. There was no statistically significant difference in the incidence of liver damage between male and female patients (68.33% and 100%, P = 0.180). There was no statistically significant difference in the incidence of liver damage among different age groups (P = 0.245). The incidence of liver damage in cirrhotic and non-cirrhotic group was 72.22%, and 63.64% (P = 0.370), respectively. The incidence of liver damage in patients with baseline Child-Pugh class A, B, and C were 71.43%, 61.11% and 100%, respectively, and the difference was not statistically significant (P = 0.878). The incidence of liver damage was not statistically significantly different under different BCLC stages (P = 1.000). The incidence of liver damage in the PD-1/PD-L1 antibody monotherapy, PD-1/PD-L1 antibody combined with targeted drug therapy, and PD-1/PD-L1 antibody combined with TACE/radiofrequency ablation treatment group were 60.00%, 67.85%, and 86.67%, respectively. There was no statistically significant difference in the incidence of liver damage between the treatment regimen (P = 0.480). Conclusion: Immune checkpoint inhibitor therapy-induced liver damage is common in patients with primary liver cancer; however, it rarely severely endangers the patient's life. Additionally, patient's gender, age, presence or absence of cirrhosis, baseline liver function, BCLC stage and the immunotherapy regimen has no effect on the incidence of immune-related liver damage.


Assuntos
Feminino , Humanos , Masculino , Inibidores de Checkpoint Imunológico , Incidência , Neoplasias Hepáticas/epidemiologia , Estudos Retrospectivos
13.
Br J Radiol ; 94(1122): 20201272, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33882244

RESUMO

OBJECTIVES: To assess the methodological quality of radiomic studies based on positron emission tomography/computed tomography (PET/CT) images predicting epidermal growth factor receptor (EGFR) mutation status in patients with non-small cell lung cancer (NSCLC). METHODS: We systematically searched for eligible studies in the PubMed and Web of Science datasets using the terms "radiomics", "PET/CT", "NSCLC", and "EGFR". The included studies were screened by two reviewers independently. The quality of the radiomic workflow of studies was assessed using the Radiomics Quality Score (RQS). Interclass correlation coefficient (ICC) was used to determine inter rater agreement for the RQS. An overview of the methodologies used in steps of the radiomics workflow and current results are presented. RESULTS: Six studies were included with sample sizes of 973 ranging from 115 to 248 patients. Methodologies in the radiomic workflow varied greatly. The first-order statistics were the most reproducible features. The RQS scores varied from 13.9 to 47.2%. All studies were scored below 50% due to defects on multiple segmentations, phantom study on all scanners, imaging at multiple time points, cut-off analyses, calibration statistics, prospective study, potential clinical utility, and cost-effectiveness analysis. The ICC results for majority of RQS items were excellent. The ICC for summed RQS was 0.986 [95% confidence interval (CI): 0.898-0.998]. CONCLUSIONS: The PET/CT-based radiomics signature could serve as a diagnostic indicator of EGFR mutation status in NSCLC patients. However, the current conclusions should be interpreted with care due to the suboptimal quality of the studies. Consensus for standardization of PET/CT-based radiomic workflow for EGFR mutation status in NSCLC patients is warranted to further improve research. ADVANCES IN KNOWLEDGE: Radiomics can offer clinicians better insight into the prediction of EGFR mutation status in NSCLC patients, whereas the quality of relative studies should be improved before application to the clinical setting.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/genética , Receptores ErbB/genética , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/genética , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Humanos , Mutação , Valor Preditivo dos Testes
14.
Opt Express ; 29(2): 1470-1480, 2021 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-33726361

RESUMO

This paper proposes an electronically reconfigurable unit cell for transmit-reflect-arrays in the X-band, which makes it possible to control the reflection or transmission phase independently by combining the mechanisms of reconfigurable transmitarrays and reconfigurable reflectarrays. The fabricated unit cell was characterized in a waveguide simulator. The return loss in the reflection mode and insertion loss in the transmission mode are smaller than 1.8 dB for all states at 10.63 GHz, and a 1-bit phase shift for both modes is achieved within 180° ± 10°. When compared to full-wave electromagnetic simulation results, the proposed unit cell shows good results and is thus verified.

15.
Clin Neuroradiol ; 31(2): 417-424, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32086545

RESUMO

PURPOSE: Blood blister-like aneurysms (BBAs) have a high risk of early recurrence and postoperative rebleeding. This study compared the clinical outcomes and complications between endovascular intervention with low-profile visualized intraluminal support (LVIS) stent-assisted coiling and the surgical clipping in patients with BBAs. METHODS: This retrospective study enrolled 39 patients with BBAs who underwent endovascular intervention with LVIS stent-assisted coiling (n = 21) or surgical clipping (n = 18) between January 2013 and July 2018. Primary outcomes were mortality and modified Rankin scale (mRS). Secondary outcomes were hospital stay, intensive care unit (ICU) stay and operation parameters. Complications were also retrospectively collated. RESULTS: At baseline, the two groups were well balanced in patient characteristics. The hospital stays, ICU stays, operation time and intraoperative infusion volume were all significantly lower in LVIS group than that in clipping group (p < 0.05). A second operation was performed in 6 cases in the clipping group but none in the LVIS group (p = 0.006). The mean mRS score in the LVIS group was significantly lower than that of the clipping group both at hospital discharge and final follow-up (p < 0.001). Adverse outcomes occurred in 1 case in LVIS group and 7 in clipping group, with significant difference (p = 0.015). Complications were reported in 8 cases in LVIS group and 16 cases in clipping group, with significant difference (p < 0.001). CONCLUSION: The endovascular intervention with LVIS stent-assisted coiling has better prognosis than surgical clipping. It decreased the risk of a second operation and procedure-related complications compared with surgical clipping.


Assuntos
Stents , Aneurisma Roto/terapia , Angiografia Cerebral , Embolização Terapêutica , Procedimentos Endovasculares , Humanos , Aneurisma Intracraniano/diagnóstico por imagem , Aneurisma Intracraniano/cirurgia , Estudos Retrospectivos , Resultado do Tratamento
16.
Huan Jing Ke Xue ; 41(9): 3899-3907, 2020 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-33124268

RESUMO

To study the seasonal pollution characteristics and sources of water-soluble inorganic ions in atmospheric PM2.5 in Suqian City, 171 samples were collected at three monitoring points, which were in the water vapor channel, from May 2017 to January 2018. The mass concentrations of PM2.5 and nine water-soluble inorganic ions were analyzed. The results showed that the annual average concentration of water-soluble inorganic ions in PM2.5 in Suqian City was (44.08±34.61) µg ·m-3, accounting for 41.8% of PM2.5. The concentrations of these species were in the order of ρ(NO3-) > ρ(SO42-) > ρ(NH4+) > ρ(ρl-) > ρ(Na+) > ρ(Ca2+) > ρ(K+) > ρ(F-) > ρ(Mg2+); NO3-, SO42-, and NH4+ accounted for 75.6% of the total water-soluble ions. The annual average ratio of ρ(NO3-) to ρ(SO42-) was 1.53±0.88, indicating that mobile sources contributed more to PM2.5 pollution. Based on the correlation analysis of NH4+ and SO42-, NO3- may exist in the form of (NH4)2 SO4, NH4HSO4, or NH4NO3. According to the principal component analysis, secondary transformation, industrial pollution, biomass burning, and dust were the major sources of water-soluble inorganic ions. PM2.5concentrations were positively related to relative humidity in winter. Water vapor transmission is more likely to promote PM2.5 accumulation in winter.


Assuntos
Poluentes Atmosféricos , Material Particulado , Aerossóis/análise , Poluentes Atmosféricos/análise , Cidades , Monitoramento Ambiental , Íons/análise , Tamanho da Partícula , Material Particulado/análise , Estações do Ano , Água
17.
Ecotoxicol Environ Saf ; 202: 110922, 2020 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-32800257

RESUMO

Fluorene-9-bisphenol (BHPF) is a substitute for bisphenol A (BPA), which is widely used to manufacture plastic products. Previous studies indicate that BHPF has an anti-estrogenic effect and induces cytotoxicity in mice oocytes. However, the effects of acute BHPF exposure on the aquatic organism obtain little attention. In this study, a series of BHPF concentrations (1 µM, 2 µM, 5 µM, 10 µM, 20 µM) was used to exposed zebrafish embryos from 2 h post-fertilization (hpf). The results showed the LC50 at 96hpf was 2.88 µM (1.01 mg/L). Acute exposure induced malformation in morphology, and retarded epiboly rate at 10hpf, increased apoptosis. Moreover, acute BHPF exposure led cardiotoxicity, by impeding cardiac looping, decreasing cardiac contractility (reducing the stroke volume and cardiac output, decreasing fractional shortening of ventricle). Besides that, BHPF exposure altered the expression of cardiac transcriptional regulators and development related genes. In conclusion, acute BHPF exposure induced developmental abnormality, retarded cardiac morphogenesis and injured the cardiac contractility. This study indicated BHPF would be an unneglected threat for the safety of aquatic organisms.


Assuntos
Compostos Benzidrílicos/toxicidade , Fenóis/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Cardiotoxicidade/metabolismo , Embrião não Mamífero/efeitos dos fármacos , Desenvolvimento Embrionário/efeitos dos fármacos , Fluorenos/toxicidade , Camundongos , Oócitos/crescimento & desenvolvimento , Plásticos , Testes de Toxicidade Aguda , Poluentes Químicos da Água/metabolismo , Peixe-Zebra
18.
Journal of Medical Postgraduates ; (12): 192-196, 2020.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-818401

RESUMO

Glucose is the basic metabolic substrate and main source of energy for the body. A complex neuroendocrine system regulate blood glucose concertration to keep it at a constant level. Thyroid hormones participate in the regulation of glucose metabolism through the PI3K/ERK and other signaling pathways. At the same time, abnormal glucose metabolism can cause the abnormal regulation of hypothalamus pituitary thyroid axis. In this paper, we review the change and molecular mechanism of thyroid hormone, thyroid stimulating hormone and thyroid releasing hormone in Hypoglycemia and Hyperglycemia.

19.
Opt Express ; 27(24): 34864-34875, 2019 Nov 25.
Artigo em Inglês | MEDLINE | ID: mdl-31878666

RESUMO

Orbital angular momentum (OAM) beam generators have attracted tremendous interests recently due to their excellent performance and potential applications in wireless communication. However, the existing transmissive OAM generators suffer from several limitations, such as narrow bandwidth, high profile and low efficiency. In this study, a new wideband third-order meta-frequency selective surface (meta-FSS) for generating focusing vortex beam is developed. The proposed meta-FSS element is designed at X- band with a third-order band-pass filter property, which exhibits the merits of low profile, high transmissivity, and large angular stability. By employing the proposed meta-FSS element, prototypes of OAM generators for + 1 and -2 modes are designed, fabricated, and measured. Experimental results verify the ability of the proposed design to convert an incident left/right-handed circularly polarized (L/RHCP) spherical wave into a transmitted R/LHCP vortex carrying OAM wave from 9.0 GHz to 11.0 GHz with high mode purity. A good agreement is achieved between the experimental and numerical results, which demonstrates that the proposed structure paves the wave for generating desired OAM modes, and provides new possibility for designing novel low-profile wireless communication devices.

20.
Neurotoxicol Teratol ; 76: 106835, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31518687

RESUMO

Venlafaxine (VEN) is one of the first clinical drugs for the treatment of depression. Long-term use may cause a potentially life-threatening serotonin syndrome. Melatonin (MT) could ameliorate depression behavior. Therefore, the aim of this study was to investigate the antidepressant effects of venlafaxine in combination with melatonin on zebrafish. Reserpine was used to induce depression-like behavioral zebrafish. To explore the effects of combined use of venlafaxine and melatonin on depression-like zebrafish induced by reserpine. We tested the depressive behavior of adult zebrafish through a novel tank test, and evaluated the levels of serotonin (5-HT), dopamine (DA) and noradrenaline (NA) in zebrafish brain using enzyme-linked immunosorbent assay (ELISA), besides that the gene expression of serotonin transporters a (serta), dopamine transporters (dat) and norepinephrine transporters (net), vesicular monoamine transporter2 (vmat2) and monoamine oxidase (mao) were evaluated by qRT-PCR. The results showed that, compared with reserpine-only group, venlafaxine (VEN, 0.025 mg/L) and melatonin (MT, 1 µM) increased the parameters of exploration in the top of the tank and decreased freezing behavior significantly. Compared with reserpine-only group, the use of VEN combined with MT increased serotonin and norepinephrine levels significantly, while there was no obvious difference in dopamine content. The results of qRT-PCR showed that the use of VEN combined with MT significantly reduced the expression of serta and promoted the expression of vmat2, but had no significant effect on the expression of net, dat and mao. The results indicated that venlafaxine combined with melatonin showed more effective role to remedy the depressive symptoms in zebrafish, providing a reference for the clinical application of antidepressants.


Assuntos
Antidepressivos de Segunda Geração/uso terapêutico , Comportamento Animal/efeitos dos fármacos , Depressão/tratamento farmacológico , Depressão/psicologia , Melatonina/uso terapêutico , Cloridrato de Venlafaxina/uso terapêutico , Animais , Depressão/induzido quimicamente , Dopamina/metabolismo , Quimioterapia Combinada , Expressão Gênica/efeitos dos fármacos , Masculino , Norepinefrina/metabolismo , Reserpina , Serotonina/metabolismo , Proteínas Vesiculares de Transporte de Monoamina/biossíntese , Proteínas Vesiculares de Transporte de Monoamina/genética , Proteínas Vesiculares de Transporte de Monoamina/metabolismo , Peixe-Zebra
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