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1.
Nature ; 600(7887): 81-85, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34853456

RESUMO

Understanding the structure and dynamic process of water at the solid-liquid interface is an extremely important topic in surface science, energy science and catalysis1-3. As model catalysts, atomically flat single-crystal electrodes exhibit well-defined surface and electric field properties, and therefore may be used to elucidate the relationship between structure and electrocatalytic activity at the atomic level4,5. Hence, studying interfacial water behaviour on single-crystal surfaces provides a framework for understanding electrocatalysis6,7. However, interfacial water is notoriously difficult to probe owing to interference from bulk water and the complexity of interfacial environments8. Here, we use electrochemical, in situ Raman spectroscopic and computational techniques to investigate the interfacial water on atomically flat Pd single-crystal surfaces. Direct spectral evidence reveals that interfacial water consists of hydrogen-bonded and hydrated Na+ ion water. At hydrogen evolution reaction (HER) potentials, dynamic changes in the structure of interfacial water were observed from a random distribution to an ordered structure due to bias potential and Na+ ion cooperation. Structurally ordered interfacial water facilitated high-efficiency electron transfer across the interface, resulting in higher HER rates. The electrolytes and electrode surface effects on interfacial water were also probed and found to affect water structure. Therefore, through local cation tuning strategies, we anticipate that these results may be generalized to enable ordered interfacial water to improve electrocatalytic reaction rates.

2.
Angew Chem Int Ed Engl ; 61(5): e202112749, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-34806809

RESUMO

Plasmonic metals under photoexcitation can generate energetic hot electrons to directly induce chemical reactions. However, the capability and fundamental insights of the transportation of these hot electrons at plasmonic metal-2D material interfaces remain unclear. Herein, hot-electron transfer at Au-graphene interfaces has been in situ studied using surface-enhanced Raman spectroscopy (SERS) with atomic layer accuracy. Combining in situ SERS studies with density functional theory calculations, it is proved that hot electrons can be injected from plasmonic Au nanoparticles to graphene and directly penetrate graphene to trigger photocatalytic reactions. With increasing graphene layers, the transportation of hot electrons decays rapidly and would be completely blocked after five layers of graphene. Moreover, the transfer of hot electrons can be modulated by applying an external electric field, and the hot-electron transfer efficiency under electrochemical conditions is improved by over three times in the presence of a monolayer of graphene.

3.
Acta Pharmacol Sin ; 41(10): 1314-1327, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32203078

RESUMO

Gastrodin (GAS) is the main bioactive component of Tianma, a traditional Chinese medicine widely used to treat neurological disorders as well as cardio- and cerebrovascular diseases. In the present study, the protective effects of GAS on H9c2 cells against ischemia-reperfusion (IR)-like injury were found to be related to decreasing of oxidative stress. Furthermore, GAS could protect H9c2 cells against oxidative injury induced by H2O2. Pretreatment of GAS at 20, 50, and 100 µM for 4 h significantly ameliorated the decrease in cell viability and increase in apoptosis of H9c2 cells treated with 400 µM H2O2 for 3 h. Furthermore, we showed that H2O2 treatment induced fragmentation of mitochondria and significant reduction in networks, footprint, and tubular length of mitochondria; H2O2 treatment strongly inhibited mitochondrial respiration; H2O2 treatment induced a decrease in the expression of mitochondrial fusion factors Mfn2 and Opa1, and increase in the expression of mitochondrial fission factor Fis1. All these alterations in H2O2-treated H9c2 cells could be ameliorated by GAS pretreatment. Moreover, we revealed that GAS pretreatment enhanced the nuclear translocation of Nrf2 under H2O2 treatment. Knockdown of Nrf2 expression abolished the protective effects of GAS on H2O2-treated H9c2 cells. Our results suggest that GAS may protect H9c2 cardiomycytes against oxidative injury via increasing the nuclear translocation of Nrf2, regulating mitochondrial dynamics, and maintaining the structure and functions of mitochondria.


Assuntos
Álcoois Benzílicos , Cardiotônicos , Glucosídeos , Mitocôndrias , Dinâmica Mitocondrial , Miócitos Cardíacos , Estresse Oxidativo , Animais , Ratos , Apoptose/efeitos dos fármacos , Álcoois Benzílicos/farmacologia , Cardiotônicos/farmacologia , Linhagem Celular , Técnicas de Silenciamento de Genes , Glucosídeos/farmacologia , Peróxido de Hidrogênio/farmacologia , Mitocôndrias/metabolismo , Dinâmica Mitocondrial/efeitos dos fármacos , Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fator 2 Relacionado a NF-E2
4.
Angew Chem Int Ed Engl ; 59(52): 23554-23558, 2020 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-32918778

RESUMO

The adsorption and electrooxidation of CO molecules at well-defined Pt(hkl) single-crystal electrode surfaces is a key step towards addressing catalyst poisoning mechanisms in fuel cells. Herein, we employed in situ electrochemical shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) coupled with theoretical calculation to investigate CO electrooxidation on Pt(hkl) surfaces in acidic solution. We obtained the Raman signal of top- and bridge-site adsorbed CO* molecules on Pt(111) and Pt(100). In contrast, on Pt(110) surfaces only top-site adsorbed CO* was detected during the entire electrooxidation process. Direct spectroscopic evidence for OH* and COOH* species forming on Pt(100) and Pt(111) surfaces was afforded and confirmed subsequently via isotope substitution experiments and DFT calculations. In summary, the formation and adsorption of OH* and COOH* species plays a vital role in expediting the electrooxidation process, which relates with the pre-oxidation peak of CO electrooxidation. This work deepens knowledge of the CO electrooxidation process and provides new perspectives for the design of anti-poisoning and highly effective catalysts.

5.
J Am Chem Soc ; 141(31): 12192-12196, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31328527

RESUMO

Investigating the chemical nature of the adsorbed intermediate species on well-defined Cu single crystal substrates is crucial in understanding many electrocatalytic reactions. Herein, we systematically study the early stages of electrochemical oxidation of Cu(111) and polycrystalline Cu surfaces in different pH electrolytes using in situ shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS). On Cu(111), for the first time, we identified surface OH species which convert to chemisorbed "O" before forming Cu2O in alkaline (0.01 M KOH) and neutral (0.1 M Na2SO4) electrolytes; while at the Cu(poly) surface, we only detected the presence of surface hydroxide. Whereas, in a strongly acidic solution (0.1 M H2SO4), sulfate replaces the hydroxyl/oxy species. This results improves the understanding of the reaction mechanisms of various electrocatalytic reactions.

6.
Zhonghua Nan Ke Xue ; 23(9): 813-816, 2017 Sep.
Artigo em Zh | MEDLINE | ID: mdl-29726663

RESUMO

OBJECTIVE: To investigate whether the trigger effect of human menopausal gonadotropins (hMG) and human chorionic gonadotropins (hCG) attributes to the treatment of unexplainable non-obstructive azoospermia (NOA). METHODS: We retrospectively analyzed the clinical data about 282 cases of unexplainable NOA treated in the Maternity and Child Health Hospital of Guizhou Province from January 2010 to May 2017. All the patients underwent trigger treatment by intramuscular injection of hMG at 75 IU 3 times a week for 2 weeks, followed by hCG at 2 000 IU twice a week for another 2 weeks, and meanwhile took vitamin E, Levocarnitine and Tamoxifen as an adjunctive therapy. The treatment lasted 3-12 months. RESULTS: Fifty-eight of the 255 patients that completed the treatment were found with sperm in the semen after treatment, all with severe oligoasthenospermia. Forty-seven of the 58 cases received assisted reproductive technology (ART), of which 18 achieved clinical pregnancy. Semen centrifugation revealed no sperm in the other cases, of which 6 were found with epididymal sperm at epididymal and testicular biopsy after treatment and 3 of them achieved clinical pregnancy after ART. Sperm was found in the semen or at epididymal or testicular biopsy in 64 of the patients after treatment, with an effectiveness rate of 25.1%. CONCLUSIONS: Trigger treatment by injection of hMG and hCG combined with adjunctive oral medication has a certain effect on unexplainable NOA.


Assuntos
Azoospermia/tratamento farmacológico , Gonadotropina Coriônica/uso terapêutico , Fármacos para a Fertilidade Masculina/uso terapêutico , Menotropinas/uso terapêutico , Recuperação Espermática/estatística & dados numéricos , Esquema de Medicação , Epididimo , Feminino , Humanos , Injeções Intramusculares , Masculino , Gravidez , Taxa de Gravidez , Técnicas de Reprodução Assistida , Estudos Retrospectivos , Espermatozoides , Testículo
7.
J Oral Maxillofac Surg ; 73(8): 1616.e1-10, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25957873

RESUMO

PURPOSE: Obtaining a detailed dentition image is important for 3-dimensional orthognathic surgical simulation. The purpose of the present study was to evaluate the accuracy of a method using automatic superimposition of intraoral fiducial markers for integrating the digital dental model with the cone beam computed tomography (CBCT) scan. PATIENTS AND METHODS: A preliminary test was performed on a plastic skull model for the proper selection of the size and number of the fiducial markers fixed to the palatal plate. Five patients were enrolled in the present study. Plaster dental models were taken and scanned. Integration of the upper dental and occlusion dental image with the CBCT scan was performed by superimposition of the markers. The occlusion dental image was used to connect the lower dental image and the corresponding position of the CBCT mandibular dentition. The root mean square difference (RMSD) was used to evaluate the accuracy of fiducial marker superimposition, and the Euclidean distances were measured between 2 occlusion surfaces to evaluate the registration accuracy. RESULTS: The RMSD was less than 0.13 mm in the superimposition of fiducial markers, and the Euclidean distance was less than 0.28 mm in the occlusal surface deviation. The results showed high accuracy on integration. The patients reported good tolerance to the markers. CONCLUSION: This superimposition method provided high accuracy for the replacement of dentition using CBCT and was patient- and user-friendly for clinical application.


Assuntos
Automação , Tomografia Computadorizada de Feixe Cônico , Modelos Anatômicos , Modelos Dentários , Palato/diagnóstico por imagem , Humanos
8.
World J Urol ; 32(1): 91-7, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23666265

RESUMO

PURPOSE: The purpose of the study is to explore the function of P2X3 and NK1 receptors antagonists on cyclophosphamide (CYP)-induced cystitis in rats. METHODS: Sixty female Sprague-Dawley (SD) rats were randomly divided into three groups. The rats in the control group were intraperitoneally (i.p.) injected with 0.9% saline (4 ml/kg); the rats in the model group were i.p. injected with CYP (150 mg/kg); and the rats in the intervention group were i.p. injected with CYP with subsequently perfusion of bladder with P2X3 and NK1 receptors' antagonists, Suramin and GR 82334. Spontaneous pain behaviors following the administration of CYP were observed. Urodynamic parameters, bladder pressure-volume curve, maximum voiding pressure (MVP), and maximum cystometric capacity (MCC), were recorded. Pathological changes in bladder tissue were observed. Immunofluorescence was used to detect the expression of P2X3 and NK1 receptors in bladder. RESULTS: Cyclophosphamide treatment increased the spontaneous pain behaviors scores. The incidence of bladder instability during urine storage period of model group was significantly higher than intervention group (χ(2) = 7.619, P = 0.007) and control group (χ(2) = 13.755, P = 0.000). MCC in the model group was lower than the control and intervention groups (P < 0.01). Histological changes evident in model and intervention groups rats' bladder included edema, vasodilation, and infiltration of inflammatory cells. In model group, the expression of P2X3 receptor increased in urothelium and suburothelium, and NK1 receptor increased in suburothelium, while the expression of them in intervention group was lower. CONCLUSIONS: In CYP-induced cystitis, the expression of P2X3 and NK1 receptors increased in urothelium and/or suburothelium. Perfusion of bladder with P2X3 and NK1 receptors antagonists ameliorated the bladder function.


Assuntos
Ciclofosfamida/efeitos adversos , Cistite/induzido quimicamente , Cistite/tratamento farmacológico , Antagonistas dos Receptores de Neurocinina-1/uso terapêutico , Fisalemina/análogos & derivados , Antagonistas do Receptor Purinérgico P2/uso terapêutico , Suramina/uso terapêutico , Animais , Cistite/patologia , Modelos Animais de Doenças , Feminino , Antagonistas dos Receptores de Neurocinina-1/farmacologia , Dor/tratamento farmacológico , Fisalemina/farmacologia , Fisalemina/uso terapêutico , Antagonistas do Receptor Purinérgico P2/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores da Neurocinina-1/efeitos dos fármacos , Receptores da Neurocinina-1/metabolismo , Receptores Purinérgicos P2X3/efeitos dos fármacos , Receptores Purinérgicos P2X3/metabolismo , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia , Suramina/farmacologia , Bexiga Urinária/efeitos dos fármacos , Bexiga Urinária/metabolismo , Bexiga Urinária/patologia , Micção/efeitos dos fármacos , Micção/fisiologia , Urodinâmica/efeitos dos fármacos , Urodinâmica/fisiologia
9.
Vascul Pharmacol ; 154: 107251, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38052330

RESUMO

BACKGROUND: Hypertension is a prevalent cardiovascular disease characterized by elevated blood pressure and increased vascular resistance. HDAC inhibitors have emerged as potential therapeutic agents due to their ability to modulate gene expression and cellular processes. YPX-C-05, a novel hydroxamic acid-based HDAC inhibitor, shows promise in its vasodilatory effects and potential targets for hypertension treatment. In this study, we aimed to elucidate the mechanisms underlying YPX-C-05's vasodilatory effects and explore its therapeutic potential in hypertension. METHODS: To determine the ex vivo vasodilatory effects of YPX-C-05, isolated aortic rings precontracted with phenylephrine were used. We assessed YPX-C-05's inhibitory effects on HDACs and its impact on histone H4 deacetylation levels in endothelial cells. Network pharmacology analysis was employed to predict putative targets of YPX-C-05 for hypertension treatment. To investigate the involvement of the PI3K/Akt/eNOS pathway, we employed enzyme-linked immunosorbent assay and to assess the levels of NO, ET-1, BH2, and BH4 in human umbilical vein endothelial cells. And we also analyzed the mRNA expression of eNOS and ET-1. Furthermore, Western blotting was conducted to quantify the phosphorylated and total Akt and eNOS levels in human umbilical vein endothelial cell lysates following treatment with YPX-C-05. In order to elucidate the vasodilatory mechanism of YPX-C-05, we employed pharmacological inhibitors for evaluation purposes. Furthermore, we evaluated the chronic antihypertensive effects of YPX-C-05 on N-omega-nitro-L-arginine-induced hypertensive mice in an in vivo model. Vascular remodeling was assessed through histological analysis. RESULTS: Our findings demonstrated that YPX-C-05 exerts significant vasodilatory effects in isolated aortic rings precontracted with phenylephrine. Furthermore, YPX-C-05 exhibited inhibitory effects on HDACs and increased histone H4 acetylation in endothelial cells. Network pharmacology analysis predicted YPX-C-05 might activate endothelial eNOS via PI3K/Akt signaling pathway. Inhibition of the PI3K/Akt/eNOS pathway attenuated the vasodilatory effects of YPX-C-05, as evidenced by reduced levels of phosphorylated Akt and eNOS in human umbilical vein endothelial cell lysates. The chronic administration of YPX-C-05 in N-omega-nitro-L-arginine-induced hypertensive mice resulted in significant antihypertensive effects. Histological analysis demonstrated a reduction in vascular remodeling, further supporting the therapeutic potential of YPX-C-05 in hypertension. CONCLUSION: This study demonstrates for the first time that the novel hydroxamic acid-based HDAC inhibitor YPX-C-05 produces significant antihypertensive and vasodilatory effects through the PI3K/Akt/eNOS pathway. Our findings support the developing prospect of YPX-C-05 as a novel antihypertensive drug.


Assuntos
Hipertensão , Proteínas Proto-Oncogênicas c-akt , Humanos , Animais , Camundongos , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/farmacologia , Anti-Hipertensivos/farmacologia , Remodelação Vascular , Inibidores de Histona Desacetilases/farmacologia , Inibidores de Histona Desacetilases/metabolismo , Histonas/metabolismo , Histonas/farmacologia , Hipertensão/tratamento farmacológico , Hipertensão/metabolismo , Células Endoteliais da Veia Umbilical Humana/metabolismo , Arginina , Fenilefrina/metabolismo , Fenilefrina/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo
10.
Zhonghua Nan Ke Xue ; 19(9): 802-5, 2013 Sep.
Artigo em Zh | MEDLINE | ID: mdl-24386858

RESUMO

OBJECTIVE: To evaluate a new puncture needle with multiple holes (National Invention Patent of China: ZL 2010202466554) in testicular sperm extraction for infertile males. METHODS: This study included 215 azoospermia patients, who underwent testicular sperm extraction with a new puncture needle with multiple holes (group A, n = 133), by open biopsy (group B, n = 37), or with a fine needle (group C, n = 45). RESULTS: The first-time success rate was 100% in group A, 19% in B and 100% in C. The average operation time was obviously shorter in group A ([3 +/- 1] min) than in B ([15 +/- 3] min) and C ([7 +/- 2] min). The rate of postoperative complications was 3.0% in group A, significantly lower than in B (21.6%) and C (11.1%). CONCLUSION: The new puncture needle with multiple holes, with its advantages of accuracy, high first-time success rate, minimal invasiveness and low rate of complications, deserves to be generally applied in testicular sperm extraction.


Assuntos
Biópsia/instrumentação , Infertilidade Masculina/terapia , Agulhas , Recuperação Espermática , Testículo , Adulto , Biópsia/métodos , Humanos , Masculino , Punções , Adulto Jovem
11.
Front Microbiol ; 14: 1137369, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37065141

RESUMO

Background: Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is associated with high mortality rates. Viral and bacterial coinfection is the primary cause of AECOPD. How coinfection with these microbes influences host inflammatory response and the gut microbiota composition is not entirely understood. Methods: We developed a mouse model of AECOPD by cigarette smoke exposure and sequential infection with influenza H1N1 virus and non-typeable Haemophilus influenzae (NTHi). Viral and bacterial titer was determined using MDCK cells and chocolate agar plates, respectively. The levels of cytokines, adhesion molecules, and inflammatory cells in the lungs were measured using Bio-Plex and flow cytometry assays. Gut microbiota was analyzed using 16S rRNA gene sequencing. Correlations between cytokines and gut microbiota were determined using Spearman's rank correlation coefficient test. Results: Coinfection with H1N1 and NTHi resulted in more severe lung injury, higher mortality, declined lung function in COPD mice. H1N1 enhanced NTHi growth in the lungs, but NTHi had no effect on H1N1. In addition, coinfection increased the levels of cytokines and adhesion molecules, as well as immune cells including total and M1 macrophages, neutrophils, monocytes, NK cells, and CD4 + T cells. In contrast, alveolar macrophages were depleted. Furthermore, coinfection caused a decline in the diversity of gut bacteria. Muribaculaceae, Lactobacillus, Akkermansia, Lachnospiraceae, and Rikenella were further found to be negatively correlated with cytokine levels, whereas Bacteroides was positively correlated. Conclusion: Coinfection with H1N1 and NTHi causes a deterioration in COPD mice due to increased lung inflammation, which is correlated with dysbiosis of the gut microbiota.

12.
Breast Cancer Res Treat ; 135(3): 737-47, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22923236

RESUMO

Drug resistance remains a major hurdle to successful cancer treatment. Many mechanisms such as overexpression of multidrug-resistance related proteins, increased drug metabolism, decreased apoptosis, and impairment of signal transduction pathway can contribute multidrug resistance (MDR). Recent studies strongly suggest a close link between cytokines and drug resistance. To identify new targets involved in drug resistance, we established a multidrug-resistant human breast cancer cell line MCF-7/R and examined the cytokine profile using cytokine antibody array technology. Among 120 cytokines/chemokines screened, IL-6, IL-8, and 13 other proteins were found to be markedly increased in drug-resistant MCF-7/R cell line as compared to sensitive MCF-7/S cell line, while 7 proteins were specifically reduced in drug-resistant MCF-7/R cells. Neutralizing antibodies against IL-6 and IL-8 partially reversed the drug resistance of MCF-7/R to paclitaxel and doxorubicin, while a neutralizing antibody against MCP-1 had no significant effect. Inhibition of endogenous IL-6 or IL-8 by siRNA technology significantly enhanced drug sensitivity of MCF-7/R cells. Furthermore, overexpression of IL-6 or IL-8 expression by transfection increased the ADM resistance in MCF-7/S cells. Our data suggest that increased expression levels of IL-6 and IL-8 may contribute to MDR in human breast cancer cells.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Interleucina-6/metabolismo , Interleucina-8/metabolismo , Anticorpos Neutralizantes/farmacologia , Antineoplásicos/farmacologia , Sequência de Bases , Linhagem Celular Tumoral , Quimiocina CCL2/metabolismo , Citocinas/genética , Citocinas/imunologia , Citocinas/metabolismo , Doxorrubicina/farmacologia , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Interleucina-6/antagonistas & inibidores , Interleucina-6/genética , Interleucina-8/antagonistas & inibidores , Interleucina-8/genética , Células MCF-7 , Dados de Sequência Molecular , Paclitaxel/farmacologia , RNA Interferente Pequeno , Receptores de Interleucina-6/genética , Receptores de Interleucina-8/genética
13.
Neurochem Res ; 37(10): 2213-21, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22832950

RESUMO

Alzheimer's disease (AD) is pathologically characterized by presence of senile plaques in the hippocampus, which are composed mainly of extracellular deposition of a polypeptide known as the beta amyloid, the Aß. It has been demonstrated on numerous occasions that it was the deposition and aggregation of this Aß peptide that cause neuronal dysfunction and even finally, the dementia. Lowering the deposition of Aß or decreasing its neurotoxicity has long been one of the purposes of AD therapy. In previous study, we reported that protein kinase C (PKC) activator TPPB could regulate APP processing by increasing α-secretase activity. In this study we further investigated the potential neuroprotective effect of TPPB against Aß(25-35)-induced neurotoxicity in PC12 cells. The results indicated that TPPB at concentration of 1 µM could antagonize Aß(25-35) induced cell damage as evidenced by MTT assays, LDH release and by morphological changes. Furthermore, the neuroprotection in cell viability can be blocked by inhibitors of PKC, Akt and MAPK. The experiment also indicated that TPPB could increase the phosphorylation of Akt, PKC, MARCKS and MAPK, which were inhibited by Aß(25-35) treatment. Finally, TPPB inhibited the activation of caspase-3 induced by Aß(25-35). Taken together, the experiment here implies that TPPB has a role against Aß(25-35)-induced neurotoxicity in PC12 cells and may suggest its therapeutic potential in AD.


Assuntos
Peptídeos beta-Amiloides/antagonistas & inibidores , Benzopiranos/farmacologia , Ativadores de Enzimas/farmacologia , Proteína Quinase C/metabolismo , Animais , Western Blotting , Caspase 3/metabolismo , Ativação Enzimática , Ensaio de Imunoadsorção Enzimática , Células PC12 , Fosforilação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Ratos
14.
ACS Omega ; 7(27): 23555-23565, 2022 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-35847330

RESUMO

Hexavalent chromium (Cr(VI)) pollution is a global problem, and the reduction of highly toxic Cr(VI) to less toxic Cr(III) is considered to be an effective method to address Cr(VI) pollution. In this study, low-toxicity carbon quantum dots (CQDs) were used to reduce Cr(VI) in wastewater. The results show that CQDs can directly reduce Cr(VI) at pH 2 and can achieve a reduction efficiency of 94% within 120 min. It is observed that under pH higher than 2, CQDs can activate peroxymonosulfate (PMS) to produce reactive oxygen species (ROS) for the reduction of Cr(VI) and the reduction efficiency can reach 99% within 120 min even under neutral conditions. The investigation of the mechanism shows that the hydroxyl groups on the surface of CQDs can be directly oxidized by Cr(VI) because of the higher redox potential of Cr(VI) at pH 2. As the pH increases, the carbonyl groups on the surface of CQDs can activate PMS to generate ROS, O2 •-, and 1O2, which result in Cr(VI) being reduced. To facilitate the practical application of CQDs, the treatment of Cr(VI) in real water samples by CQDs was simulated and the method reduced Cr(VI) from an initial concentration of 5 mg/L to only 8 µg/L in 150 min, which is below the California water quality standard of 10 µg/L. The study provides a new method for the removal of Cr(VI) from wastewater and a theoretical basis for practical application.

15.
Beijing Da Xue Xue Bao Yi Xue Ban ; 43(4): 519-21, 2011 Aug 18.
Artigo em Zh | MEDLINE | ID: mdl-21844957

RESUMO

OBJECTIVE: To investigate the architectural features and frequency of glomeruloid features in pathological section of prostatic adenocarcinoma and evaluate the association between glomerulations and its clinical data. METHODS: We studied 196 prostatic adenocarcinoma specimens obtained from needle biopsies or radical prostatectomy and their clinical data, and reviewed related literatures. RESULTS: Three of the 196 cases showed glomeruloid features, the Gleason score of which was 7, 8, and 8, respectively. Of the 3 cases 1 had osseous metastasis and 2 extraprostatic nervus extension. After 5 to 15 months' follow-up, 1 case died and the other 2 still under treatment. CONCLUSION: Glomeruloid structures in the prostate represented an uncommon but distinctive growth pattern that was specific for malignancy. Glomeruloid structures were usually seen in high-grade adenocarcinoma, often with extraprostatic extension.


Assuntos
Adenocarcinoma/patologia , Neoplasias da Próstata/patologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Retrospectivos
16.
Nat Prod Bioprospect ; 11(6): 659-670, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34750765

RESUMO

Flavonoid glycoside scutellarin (SCU) has been widely applied in the treatment of cerebral ischemic diseases in China. In this article, we conducted research on the working mechanisms of SCU in hypoxia reoxygenation (HR) injury of isolated cerebral basilar artery (BA) and erebral ischemia reperfusion (CIR) injury in rat models. In isolated rat BA rings, HR causes endothelial dysfunction (ED) and acetylcholine (ACh) induces endothelium-dependent vasodilation. The myography result showed that SCU (100 µM) was able to significantly improve the endothelium-dependent vasodilation induced by Ach. However, SCU did not affect the ACh-induced relaxation in normal BA. Further studies suggested that SCU (10-1000 µM) dose-dependently induced relaxation in isolated BA rings which were significantly blocked by the cGMP dependent protein kinase (PKG) inhibitor Rp-8-Br-cGMPs (PKGI-rp, 4 µM). Pre-incubation with SCU (500 µM) reversed the impairment of endothelium-dependent vasodilation induced by HR, but the reversing effect was blocked if PKGI-rp (4 µM) was added. The brain slice staining test in rats' model of middle cerebral artery occlusion (MCAO) induced CIR proved that the administration of SCU (45, 90 mg/kg, iv) significantly reduced the area of cerebral infarction. The Western blot assay result showed that SCU (45 mg/kg, iv) increased brain PKG activity and PKG protein level after CIR surgery. In conclusion, our findings suggested that SCU possesses the ability of protecting brain cells against CIR injury through vascular endothelium protection and PKG signal.

17.
Zhonghua Wai Ke Za Zhi ; 48(23): 1767-70, 2010 Dec 01.
Artigo em Zh | MEDLINE | ID: mdl-21211379

RESUMO

OBJECTIVE: To investigate the urodynamic features in patients of benign prostatic hyperplasia (BPH) with coexisting overactive bladder (OAB). METHODS: Clinical data of 235 patients with symptomatic BPH who underwent urodynamic examination during January 2009 to May 2010 were retrospectively analyzed. Patients were divided into group of pure BPH, BPH with detrusor overactivity (DO), BPH with coexisting OAB without DO and BPH with coexisting OAB with DO. The difference of age, International Prostate Symptom Score (IPSS), transrectal ultrasound (TRUS)-volume, maximum flow rate, residual urine volume, bladder volume of first sensation, bladder volume of strong sensation, bladder outlet obstruction index (BOOI) and the prevalence of decreased detrusor contractility were compared between these groups. The urodynamic characteristics of DO between group of BPH with DO and group of BPH coexisting OAB and DO were analyzed. RESULTS: A total of 219 cases were included in the final analysis, with mean age of (66 ± 8) years, mean TRUS-volume was (35 ± 24) ml, mean maximum flow rate was (11 ± 6) ml/s. Of the 219 patients, 93 patients (42.5%) had pure BPH, 11 patients (5.0%) had BPH with DO, 52 patients (23.7%) had BPH coexisting OAB without DO, 63 patients (28.8%) had BPH coexisting OAB and DO. Comparing to group of BPH (n = 104), patients with BPH and OAB (n = 115) were older, had higher IPSS, bigger TRUS-volume, less bladder volume of first sensation and strong sensation, higher BOOI and higher prevalence of decreased detrusor contractility. Comparing to group of BPH with coexisting OAB without DO patients, patients of BPH with coexisting OAB and DO had higher IPSS score (19 ± 12 vs 17 ± 10), bigger TRUS-volume [(51 ± 33) ml vs (43 ± 27) ml], higher BOOI (49 ± 18 vs 37 ± 14). Comparing to patients pure BPH, patients of BPH with DO had less bladder volume of first sensation and bladder volume of strong sensation [(82 ± 41) ml vs (118 ± 35) ml;(335 ± 67) ml vs (419 ± 53) ml]. Comparing to group of BPH with DO, patients of BPH with coexisting OAB and DO had higher maximum DO pressure [(45 ± 36) cmH2O vs (39 ± 30) cmH2O (1 cmH2O = 0.098 kPa)] and longer DO time [(7 ± 4) s vs (6 ± 4) s]. CONCLUSIONS: The urodynamic features in patients with BPH differ greatly and these information should be helpful in making choice of treatment and in predicting treatment outcomes.


Assuntos
Hiperplasia Prostática/fisiopatologia , Bexiga Urinária Hiperativa/fisiopatologia , Idoso , Idoso de 80 Anos ou mais , Humanos , Masculino , Pessoa de Meia-Idade , Hiperplasia Prostática/complicações , Estudos Retrospectivos , Bexiga Urinária Hiperativa/complicações , Urodinâmica
18.
Chem Sci ; 11(25): 6431-6435, 2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-34094107

RESUMO

In dye-sensitized solar cells (DSSCs), the TiO2/dye interface significantly affects photovoltaic performance. However, the adsorption and photoinduced behavior of dye molecules on the TiO2 substrate remains unclear. Herein, shell-isolated nanoparticle-enhanced Raman spectroscopy (SHINERS) was used to study the adsorption and photoinduced behavior of dye (N719) molecules on different TiO2(hkl) surfaces. On TiO2(001) and TiO2(110) surfaces, the in situ SHINERS and mass spectrometry results indicate S[double bond, length as m-dash]C bond cleavage in the anchoring groups of adsorbed N719, whereas negligible bond cleavage occurs on the TiO2(111) surface. Furthermore, DFT calculations show the stability of the S[double bond, length as m-dash]C anchoring group on three TiO2(hkl) surfaces in the order TiO2(001) < TiO2(110) < TiO2(111), which correlated well with the observed photocatalytic activities. This work reveals the photoactivity of different TiO2(hkl) surface structures and can help with the rational design of DSSCs. Thus, this strategy can be applied to real-time probing of photoinduced processes on semiconductor single crystal surfaces.

19.
Nanoscale ; 12(9): 5341-5346, 2020 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-32091518

RESUMO

In situ monitoring of electrocatalytic processes at solid-liquid interfaces is essential for the fundamental understanding of reaction mechanisms, yet quite challenging. Herein, Pt-on-Au nanocatalysts with a Au-core Pt-satellite superstructure have been fabricated. In such Pt-on-Au nanocatalysts, the Au cores can greatly amplify the Raman signals of the species adsorbed on Pt, allowing the in situ surface-enhanced Raman spectroscopy (SERS) study of the electrocatalytic reactions on Pt. Using the combination of an electrochemical method and in situ SERS, size effects of Pt on the catalytic performance of the core-satellite nanocomposites towards CO and methanol electrooxidation are revealed. It is found that such Pt-on-Au nanocomposites show improved activity and long-term stability for the electrooxidation of CO and methanol with a decrease in the Pt size. This work demonstrates an effective strategy to achieve the in situ monitoring of electrocatalytic processes and to simultaneously boost their catalytic performance towards electrooxidation.

20.
Zhonghua Yi Xue Za Zhi ; 89(26): 1854-7, 2009 Jul 14.
Artigo em Zh | MEDLINE | ID: mdl-19953934

RESUMO

OBJECTIVE: To investigate the mechanisms of erectile dysfunction induced by hyperlipidemia through studying the changes of contractility and relaxation of corpus cavernosum in hypercholesterolemic rabbit in vitro. METHODS: New Zealand white rabbits were randomly divided into control and experiment groups. The control group (n = 20) received a regular diet for 8 weeks while the experimental group (n = 20) were fed a 1% cholesterol diet for 8 weeks. The authors conducted isometric tension studies with phenylephrine, endothelium-dependent vasodilators (acetylcholine), endothelium-independent vasodilators (sodium nitroprusside) and rho kinase inhibitor (Fasudil) on isolated strips of corpus cavernosum. RESULTS: The weight and total serum cholesterol significantly improved (P < 0.01) in experimental group as compared with the non-fed experimental group. The total serum cholesterol significantly improved (P < 0.01) in experimental group as compared with the control group. The contractility responses to phenylephrine in experiment group in doses (0.5, 1, 5, 10, 50, 100 micromol) were 4.79% +/- 2.00%, 8.84% +/-2.95%, 12.81% +/- 3.77%, 14.63% +/- 5.38%, 25.01% +/- 6.14% and 34.69% +/- 8.53% respectively. The contractility responses to phenylephrine in control group were 1.00% +/- 0.3%, 2.60% +/- 0.72%, 4.28% +/- 1.27%, 5.91% +/- 2.09%, 6.49% +/- 4.02% and 5.64% +/- 11.87% respectively. The contractility responses to phenylephrine significantly improved (P < 0.01) in experimental group in these doses as compared with the control group. The relaxation responses to acetylcholine in experimental group in doses (1, 10 and 100 micromol) were 36.28% +/- 4.71%, 48.81% +/- 4.36% and 56.27% +/- 11.93% respectively. The relaxation responses in control group were 48.04% +/- 4.78%, 69.12% +/- 5.27% and 78.23% +/- 5.30% respectively. There was significant reduction (P < 0.01) in experimental group in these doses as compared with the control group. No difference were found among the two groups in the relaxation response to sodium nitroprusside. The relaxation responses to fasudil in experimental group in doses (0.25, 1.25, 2.5 and 12.5 micromol) were 1.56% +/- 0.43%, 5.03% +/- 1.02%, 8.28% +/- 1.35% and 16.77% +/- 3.57% respectively. The relaxation responses in control group were 4.69% +/- 1.23%, 10.39% +/- 2.05%, 15.08% +/- 3.04% and 25.22% +/- 3.72% respectively. There was significant reduction (P < 0.01) in experimental group in these doses as compared with the control group. CONCLUSION: The improvement of cavernous smooth muscle contractility and the impairment of cavernous smooth muscle relaxation in response to endothelium-mediated stimuli are the mechanisms of erectile dysfunction induced by hyperlipidemia.


Assuntos
Hiperlipidemias/fisiopatologia , Músculo Liso/fisiopatologia , Pênis/fisiopatologia , Animais , Masculino , Contração Muscular , Relaxamento Muscular , Coelhos
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