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1.
Reproduction ; 166(1): 27-36, 2023 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-37140983

RESUMO

In brief: The current declining trend in male fertility parallels the increasing prevalence of obesity worldwide. This paper revealed that the poor in vitro fertilization rates and decreased sperm motility in obese mice due to excessive oxidative stress enhanced apoptosis and impaired glucose metabolism in the testes. Abstract: Obesity is an urgent public health problem in recent decades, linked to reduced reproductive potential, and negatively affects the success of assisted reproduction technology. The aim of this study is to investigate the mechanisms underlying impaired male fertility caused by obesity. Male C57BL/6 mice fed a high-fat diet for 20 weeks served as mouse models with moderate (20% < body fat rate (BFR) < 30%) and severe obesity (BFR > 30%). Our results showed poor in vitro fertilization rates and decreased sperm motility in obese mice. Abnormal testicular structures were identified in male mice with moderate and severe obesity. The expression level of malondialdehyde increased with obesity severity. This finding indicates that oxidative stress plays a role in male infertility caused by obesity, which was further confirmed by the decreased expression of nuclear factor erythroid 2-related factor 2, superoxide dismutase, and glutathione peroxidases. Our study also found that the expression of cleaved caspase-3 and B-cell lymphoma-2 showed an obesity severity-dependent manner indicating that apoptosis is highly correlated with male infertility caused by obesity. Moreover, the expression of glycolysis-related proteins, including glucose transporter 8, lactate dehydrogenase A, monocarboxylate transporter 2 (MCT2), and MCT4, decreased significantly in the testes of obese male mice, suggesting energy supply for spermatogenesis is impaired by obesity. Taken together, our findings provide evidence that obesity impairs male fertility through oxidative stress, apoptosis, and blockage of energy supply in the testes and suggest that male obesity influences fertility through complex and multiple mechanisms.


Assuntos
Infertilidade Masculina , Obesidade Mórbida , Humanos , Masculino , Camundongos , Animais , Obesidade Mórbida/complicações , Obesidade Mórbida/metabolismo , Camundongos Obesos , Motilidade dos Espermatozoides , Camundongos Endogâmicos C57BL , Obesidade/complicações , Obesidade/metabolismo , Testículo/metabolismo , Infertilidade Masculina/etiologia , Infertilidade Masculina/metabolismo , Estresse Oxidativo , Apoptose , Glicólise
2.
Artigo em Inglês | MEDLINE | ID: mdl-36288261

RESUMO

Harvesting solar energy to enhance thermoelectric generator efficiency is a highly effective strategy. However, it is a grand challenge but essential to increase solar-thermal conversion efficiency. A spectrally selective absorber, which is capable of boosting solar absorptance (α) while suppressing thermal emittance (ε), shows great potential to elevate the solar-thermal conversion efficiency. Herein, we fabricate a multilayer spectrally selective absorber with the assistance of high-entropy nitrides, which shows outstanding spectral selectivity (α/ε = 95.2/10.9%). Benefitting from the high-entropy nitrides, it is experimentally demonstrated that the as-deposited absorber exhibits superior thermal stability, which is crucial to ensure service life. Under 1000 W·m-2 simulated solar illumination, it achieves a very high surface temperature of 109.6 °C, making it suitable to enhance the efficiency of solar thermoelectric generators. Impressively, the integration of the proposed absorber with a commercial thermoelectric generator efficiently reinforces thermoelectric performance, offering a high output power of 1.99 mW. More importantly, by taking advantage of a thermal concentration strategy, it enables a further increase of the output power by 2.98 mW. This work provides a promising solar-thermal material to boost high thermoelectric performance and extends the application category of high-entropy nitrides.

3.
Adv Sci (Weinh) ; 9(30): e2202993, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-36045101

RESUMO

A malformed tumour vascular network provokes the nutrient-deprived tumour microenvironment (TME), which conversely activates endothelial cell (EC) functions and stimulates neovascularization. Emerging evidence suggests that the flexible metabolic adaptability of tumour cells helps to establish a metabolic symbiosis among various cell subpopulations in the fluctuating TME. In this study, the authors propose a novel metabolic link between bladder cancer (BCa) cells and ECs in the nutrient-scarce TME, in which BCa-secreted glutamine-fructose-6-phosphate aminotransferase 1 (GFAT1) via small extracellular vesicles (sEVs) reprograms glucose metabolism by increasing hexosamine biosynthesis pathway flux in ECs and thus enhances O-GlcNAcylation. Moreover, seryl-tRNA synthetase (SerRS) O-GlcNAcylation at serine 101 in ECs promotes its degradation by ubiquitination and impeded importin α5-mediated nuclear translocation. Intranuclear SerRS attenuates vascular endothelial growth factor transcription by competitively binding to the GC-rich region of the proximal promotor. Additionally, GFAT1 knockout in tumour cells blocks SerRS O-GlcNAcylation in ECs and attenuates angiogenesis both in vitro and in vivo. However, administration of GFAT1-overexpressing BCa cells-derived sEVs increase the angiogenetic activity in the ECs of GFAT1-knockout mice. In summary, this study suggests that inhibiting sEV-mediated GFAT1 secretion from BCa cells and targeting SerRS O-GlcNAcylation in ECs may serve as novel strategies for BCa antiangiogenetic therapy.


Assuntos
Vesículas Extracelulares , Serina-tRNA Ligase , Neoplasias da Bexiga Urinária , Camundongos , Animais , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/genética , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante)/metabolismo , Células Endoteliais/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Serina-tRNA Ligase/metabolismo , Hexosaminas/metabolismo , Serina/metabolismo , Glucose/metabolismo , Vesículas Extracelulares/metabolismo , Carioferinas , Microambiente Tumoral
4.
Anal Chem ; 94(23): 8426-8432, 2022 06 14.
Artigo em Inglês | MEDLINE | ID: mdl-35657752

RESUMO

Owing to their almost similarities in size, shape, and chemical reactivity, effectively distinguishing deuteroxide (D2O) in water (H2O) remains an ongoing challenge, and the examples of a D2O probe are still quite scarce. Herein, since H2O can decrease the lifetime of a singlet oxygen as a vital intermediate and an H/D exchange in the luminescence process of porphyrins, we systematically investigated the enhanced ultraviolet-visible (UV-vis), photoluminescence (PL), and electrochemiluminescence (ECL) of water-soluble tetrakis(carboxphenyl)porphyrin (TCPP) in D2O. The findings showed that these luminescent properties had been greatly enhanced with the increase of the D2O fraction in water. Consequently, we first developed the highly facile methods of detecting D2O in H2O by the UV-vis, PL, and ECL of TCPP, respectively. Impressively, the ECL analysis exhibited a great superiority with a lower detection limit of 0.29 nM. The work not only achieves the challenging task of distinguishing between H2O and D2O but also provides a unique strategy to enhance the luminescent performance of porphyrin.


Assuntos
Porfirinas , Luminescência , Medições Luminescentes/métodos , Porfirinas/química , Oxigênio Singlete , Água/química
5.
Ecotoxicol Environ Saf ; 238: 113608, 2022 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-35525112

RESUMO

Hexavalent chromium Cr(VI) is a well-known environmental toxic metal that causes reprotoxicity in pregnant females. There are currently no appropriate interventions or treatments for Cr(VI) exposure during pregnancy. Herein, the protective effect of melatonin (MLT) against Cr(VI)-induced reprotoxicity is investigated by administrating MLT to pregnant mice exposed to Cr(VI). The results indicate that MLT effectively alleviates Cr(VI)-induced adverse pregnancy outcomes, restoring the decreased fetal weight and increased fetal resorption and malformation caused by Cr(VI) exposure to normal levels. MLT reduces the negative effects of Cr(VI) on follicular atresia and the development of primordial follicle in the maternal ovarian, thereby mitigating the decline in the reserve of primordial follicles. MLT alleviates Cr(VI)-induced oxidative stress, hence reducing the excessive accumulation of malondialdehyde in the maternal ovary. MLT inhibits Cr(VI)-induced apoptosis of ovarian granulosa cells and the expression of cleaved caspase-3 in the ovary. MLT reduces the increase in serum follicle-stimulating hormone caused by Cr(VI) exposure, while elevating anti-Mullerian hormone levels. We demonstrate that MLT reverses Cr(VI)-induced reprotoxicity in pregnant mice, opening up a new avenue for treating reproductive defects caused by environmental stress.


Assuntos
Melatonina , Animais , Cromo/metabolismo , Feminino , Atresia Folicular , Melatonina/metabolismo , Melatonina/farmacologia , Camundongos , Ovário , Gravidez , Resultado da Gravidez
6.
Molecules ; 27(5)2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35268616

RESUMO

Cancers have always been the most difficult to fight, the treatment of cancer is still not considered. Thus, exploring new anticancer drugs is still imminent. Traditional Chinese medicine has played an important role in the treatment of cancer. Polyphenol oxidase (PPO) extracted from Edible mushroom has many related reports on its characteristics, but its role in cancer treatment is still unclear. This study aims to investigate the effects of PPO extracted from Edible mushroom on the proliferation, migration, invasion, and apoptosis of cancer cells in vitro and explore the therapeutic effects of PPO on tumors in vivo. A cell counting kit-8 (CCK8) assay was used to detect the effect of PPO on the proliferation of cancer cells. The effect of PPO on cancer cell migration ability was detected by scratch test. The effect of PPO on the invasion ability of cancer cells was detected by a transwell assay. The effect of PPO on the apoptosis of cancer cells was detected by flow cytometry. Female BALB/c mice (18-25 g, 6-8 weeks) were used for in vivo experiments. The experiments were divided into control group, model group, low-dose group (25 mg/kg), and high-dose group (50 mg/kg). In vitro, PPO extracted from Edible mushroom significantly inhibited the proliferation, migration, and invasion capability of breast cancer cell 4T1, lung cancer cell A549, and prostate cancer cell C4-2, and significantly promoted the apoptosis of 4T1, A549, and C4-2. In vivo experiments showed PPO inhibitory effect on tumor growth. Collectively, the edible fungus extract PPO could play an effective role in treating various cancers, and it may potentially be a promising agent for treating cancers.


Assuntos
Catecol Oxidase
7.
World J Clin Cases ; 10(7): 2127-2137, 2022 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-35321184

RESUMO

BACKGROUND: Patients with hematological diseases are immunosuppressed due to various factors, including the disease itself and treatments, such as chemotherapy and immunotherapy, and are susceptible to infection. Infections in these patients often progress rapidly to sepsis, which is life-threatening. AIM: To evaluate the diagnostic efficacy of the neutrophil CD64 (nCD64) index, compared to procalcitonin (PCT) and high-sensitivity C-reactive protein (hs-CRP), for the identification of early sepsis in patients with hematological diseases. METHODS: This was a prospective analysis of patients with hematological diseases treated at the Fuxing Hospital affiliated with Capital Medical University, between March 2014 and December 2018. The nCD64 index was quantified by flow cytometry and the Leuko64 assay software. The factors which may affect the nCD64 index levels were compared between patients with different infection statuses (local infection, sepsis, and no infection), and the control group and the nCD64 index levels were compared among the groups. The diagnostic efficacy of the nCD64 index, PCT, and hs-CRP for early sepsis was evaluated among patients with hematological diseases. RESULTS: A total of 207 patients with hematological diseases (non-infected group, n = 50; locally infected group, n = 67; sepsis group, n = 90) and 26 healthy volunteers were analyzed. According to the absolute neutrophil count (ANC), patients with hematological diseases without infection were divided into the normal ANC, ANC reduced, and ANC deficiency groups. There was no statistically significant difference in the nCD64 index between these three groups (P = 0.586). However, there was a difference in the nCD64 index among the non-infected (0.74 ± 0.26), locally infected (1.47 ± 1.10), and sepsis (2.62 ± 1.60) groups (P < 0.001). The area under the diagnosis curve of the nCD64 index, evaluated as the difference between the sepsis and locally infected group, 0.777, which was higher than for PCT (0.735) and hs-CRP (0.670). The positive and negative likelihood ratios were also better for the nCD64 index than either PCT and hs-CRP. CONCLUSION: Our results indicate the usefulness of the nCD64 index as an inflammatory marker of early sepsis in hematological patients.

8.
ACS Appl Mater Interfaces ; 14(1): 1950-1960, 2022 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-34958543

RESUMO

Developing advanced materials with a high-entropy concept is one of the hot trends in materials science. The configurational entropy of high-entropy materials can be tuned by introducing different atomic species, which can also impart a result in excellent physical and chemical properties. In this work, we synthesized a solid-solution oxide (Cu, Mn, Fe, Cr)3O4 by a simple and scalable solid-phase synthesis method. We extensively investigated the microstructure and chemical composition, indicating that (Cu, Mn, Fe, Cr)3O4 has a single-phase spinel structure. Simultaneously, we reasonably evaluated the position occupied by the elements of (Cu, Mn, Fe, Cr)3O4 in a spinel structure as (Cu0.75Fe0.25)(Fe0.25Cr0.375Mn0.375)2O4. Here, we first evaluated the infrared radiation performance of (Cu, Mn, Fe, Cr)3O4. The new, high-entropy oxide (HEO) (Cu, Mn, Fe, Cr)3O4 powder exhibits high infrared emissivity values of 0.879 and 0.848 in the wavelengths of 0.78-2.5 and 2.5-16 µm, respectively, and has excellent thermal stability. More importantly, the infrared emissivity values of as-prepared HEO coating reach 0.955 (0.78-2.5 µm) at room temperature and 0.936 (3-16 µm) at 800 °C. This work provides a viable strategy toward the laboratory mass production of this HEO for infrared radiation materials, which shows great potential in the energy-related applications.

9.
Anal Chem ; 93(27): 9621-9627, 2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34197082

RESUMO

Manganese dioxide nanosheets combined with cysteine-assisted emitting manganese dioxide nanospheres (Cys-MnO2 nanospheres) is fabricated for the first time as an "off-on" fluorescence detection platform for glutathione (GSH). In this sensing system, Cys-MnO2 nanospheres served as energy donors, while MnO2 nanosheets were used as both energy acceptors and recognition units. MnO2 nanosheets can effectively quench the fluorescence of Cys-MnO2 nanospheres through the fluorescence resonance energy transfer (FRET). The addition of GSH could reduce MnO2 nanosheets into Mn2+, disrupting the FRET process and restoring the fluorescence of Cys-MnO2 nanospheres. Under the optimum conditions, the "switch-on" platform we established has a wide response to GSH with a range of 5-50 µM and 150-800 µM, as well as a superior specificity. Importantly, all components of the sensor are nontoxic, biocompatible, easily prepared, and have a high utilization of raw materials. Moreover, the sensing system achieved satisfactory results in human serum, showing a tremendous potential in the field of biomedicine.


Assuntos
Glutationa/análise , Compostos de Manganês , Nanosferas , Cisteína , Transferência Ressonante de Energia de Fluorescência , Humanos , Limite de Detecção , Óxidos
10.
ACS Appl Mater Interfaces ; 13(14): 16987-16996, 2021 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-33787205

RESUMO

Recent advances in high-entropy alloys have spurred many breakthroughs in the fields of high-temperature materials and optical materials and they provide incredible application potentialities for photothermal conversion systems. Solar-selective absorbers (SSAs), as key components, play a vital role in photothermal conversion efficiency and service life. The most pressing problem with SSAs is their inconsistent optical performance, an instability constraint induced by thermal stress. A feasible method of improving performance stability is the introduction of high-entropy materials, such as high-entropy alloy nitrides. In this study, enabled by an intrinsic MoTaTiCrN absorption layer, the solar configuration achieves greatly enhanced, exceptional thermotolerance and optical properties, leading to the formation of a scalable, highly efficient, and cost-effective structure. Computational and experimental approaches are employed to achieve optimum preparation parameters for thicknesses and constituents. The crystal structure of high-entropy ceramic MoTaTiCrN is fully investigated, including thickness-dependent crystal nucleation. High-temperature and long-term thermal stability tests demonstrate that our proposed SSA is mechanically robust and chemically stable. Moreover, a low thermal emittance (15.86%) at 500 °C promotes the photothermal conversion efficiency. In addition, due to the exceptional spectral selectivity (α/ε = 92.3/6.5%), thermal robustness (550 °C for 168 h), and photothermal conversion efficiency (86.9% at 550 °C under 100 sun), it is possible for our proposed SSA to enhance the practical realization of large-area photothermal conversion applications, especially for concentrated solar power systems.

11.
Polymers (Basel) ; 12(2)2020 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-32054046

RESUMO

Micro-molecular drugs have special advantages to cope with challenging diseases, however their structure, physical and chemical properties, stability, and pharmacodynamics have more requirements for the way they are delivered into the body. Carrier-based drug delivery systems can circumvent many limited factors of drug delivery and increase their bioavailability. In this context, stable drug nanocarriers of alkaline amino acids (arginine, Arg) modified conjugated linoleic acid-carboxymethyl chitosan (CLA-CMCS) conjugate were developed, which could generate supramolecular micelles to effectively encapsulate the tyrosinase inhibitor phenylethyl resorcinol (PR). The resulting CCA-NPs were spherical nanoparticles with a mean size around 175 nm. The 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay and cellular uptake investigation demonstrated that the CCA-NPs were non-cytotoxic and had excellent cell transport ability. In addition, these CCA-NPs were able to effectively deliver PR and inhibited melanin formation to reduce pigmentation by enhancing cellular uptake. In conclusion, our research indicated that nanocarriers based on self-assembly amphiphilic polymers constituted a promising and effective drug delivery system in hyperpigmentation targeting.

12.
Zhongguo Shi Yan Xue Ye Xue Za Zhi ; 27(1): 33-38, 2019 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-30738444

RESUMO

OBJECTIVE: To investigate the clinical features of acute myeloid leukemia patients aged over 80 years. METHODS: The clinical data from 24 cases of acute myeloid leukemia (non-M3) aged over 80 years were analyzed retrospectively. Clinical characteristics, therapeutic efficacy and overall survival rate of the patients received low dose chemotherapy and/or decitabine were compared with that received only supportive care. RESULTS: According to FAB classification, the 10 patients were M2 subtypes (41.7%), the 7 patients were M4 subtypes (29.2%), the 4 patiens were M5 (16.7%), the 3 patients were unclassifed (16.5%). 22 patients (91.0%) were complicated with underling diseases. Among 13 patients received low dose chemotherapy or decitabine, 8 cases (61.5%) achived partial remission or higher remission. The median survival time of patients who reseived chemotherapy was 30 weeks, and signicantly longer than that of patients received supportive care (median survival time was 9 weeks (P<0.05)). The univariated analysis showed that WBC≥50×109/L, ECOG≥2 and received supportive care were unfavonrable prognostic factors for overall survival. CONCLUSION: More than half of patients aged over 80 years who received individudized treatment can achieve partial remission or higher remission, and can have more longer survival time..


Assuntos
Leucemia Mieloide Aguda , Idoso de 80 Anos ou mais , Decitabina , Humanos , Estudos Retrospectivos , Taxa de Sobrevida , Resultado do Tratamento
13.
Front Microbiol ; 7: 751, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27242764

RESUMO

Rabies remains a major public health concern in many developing countries. The precise neuropathogenesis of rabies is unknown, though it is hypothesized to be due to neuronal death or dysfunction. Mice that received intranasal inoculation of an attenuated rabies virus (RABV) strain HEP-Flury exhibited subtle clinical signs, and eventually recovered, which is different from the fatal encephalitis caused by the virulent RABV strain CVS-11. To understand the neuropathogenesis of rabies and the mechanisms of viral clearance, we applied RNA sequencing (RNA-Seq) to compare the brain transcriptomes of normal mice vs. HEP-Flury or CVS-11 intranasally inoculated mice. Our results revealed that both RABV strains altered positively and negatively the expression levels of many host genes, including genes associated with innate and adaptive immunity, inflammation and cell death. It is found that HEP-Flury infection can activate the innate immunity earlier through the RIG-I/MDA-5 signaling, and the innate immunity pre-activated by HEP-Flury or Newcastle disease virus (NDV) infection can effectively prevent the CVS-11 to invade central nervous system (CNS), but fails to clear the CVS-11 after its entry into the CNS. In addition, following CVS-11 infection, genes implicated in cell adhesion, blood vessel morphogenesis and coagulation were mainly up-regulated, while the genes involved in synaptic transmission and ion transport were significantly down-regulated. On the other hand, several genes involved in the MHC class II-mediated antigen presentation pathway were activated to a greater extent after the HEP-Flury infection as compared with the CVS-11 infection suggesting that the collaboration of CD4(+) T cells and MHC class II-mediated antigen presentation is critical for the clearance of attenuated RABV from the CNS. The differentially regulated genes reported here are likely to include potential therapeutic targets for expanding the post-exposure treatment window for RABV infection.

14.
Biosens Bioelectron ; 58: 85-91, 2014 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-24632133

RESUMO

In this study, an electrochemical sensor of nitro aromatic compound based on three-dimensional porous Pt-Pd nanoparticles (Pt-Pd NPs) supported by reduced graphene oxide (rGO) nanosheets-multiwalled carbon nanotube (CNTs) nanocomposite (marked as Pt-Pd NPs/CNTs-rGO) was investigated for the first time. This hybrid nanocomposite has been prepared via a facile and versatile hydrothermal synthetic strategy while its structure and property are evaluated by X-ray diffraction (XRD), transmission electron microscopy (TEM) and electrochemical impedance spectroscopy (EIS). The result shows that 3D porous Pt-Pd NPs/CNTs-rGO nanocomposite has a large specific surface area of 326.6m(2)g(-1) and exhibited ultrahigh rate capability and good cycling properties at high rates. Electrochemical studies have been performed for the nitro aromatic compounds detection by using different pulse voltammetry (DPV) techniques. The proposed nanocomposite exhibited much enhanced elctrocatalytic activity and high sensitivity toward the detection of nitro aromatic compounds which compared with Pt-Pd NPs dispersed on functionalized rGO, Pt-Pd NPs dispersed on functionalized CNTs, rGO-CNTs and bare glass carbon electrode (GCE). On the basis of the above synergetic electrochemical sensing and synthesis procedure, the hybrid material can be recommended as a robust material for sensor-related applications. Moreover, the proposed sensor exhibits high reproducibility, long-time storage stability and satisfactory anti-interference ability.


Assuntos
Condutometria/instrumentação , Grafite/química , Hidrocarbonetos Aromáticos/análise , Nanotubos de Carbono/química , Nitrocompostos/análise , Paládio/química , Platina/química , Desenho de Equipamento , Análise de Falha de Equipamento , Hidrocarbonetos Aromáticos/química , Nanopartículas Metálicas/química , Microeletrodos , Conformação Molecular , Nanocompostos/química , Nanocompostos/ultraestrutura , Nanoporos/ultraestrutura , Nanotubos de Carbono/ultraestrutura , Nitrocompostos/química , Porosidade
15.
Analyst ; 137(6): 1416-20, 2012 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-22290275

RESUMO

Electrochemiluminescence (ECL) of Ru(bpy)(3)(2+) using metabolites of catecholamines: homovanillic acid (HVA) and vanillylmandelic acid (VMA) as co-reactants were investigated in aqueous solution for the first time. When HVA and VMA were co-existent in the buffer solution containing Ru(bpy)(3)(2+), ECL peaks were observed at a potential corresponding to the oxidation of Ru(bpy)(3)(2+), and the ECL intensity was increased noticeably when the concentrations of HVA and VMA were at lower levels. The linear calibration range was from 8.0 × 10(-5) to 1.0 × 10(-9) M for HVA and VMA. The detection limit (S/N = 3) of HVA and VMA was 4.0 × 10(-10) M. The formation of the excited state Ru(bpy)(3)(2+*) was confirmed to result from the reaction between Ru(bpy)(3)(3+) and the intermediates of HVA or VMA radicals. Moreover, it was found that the ECL intensity was quenched significantly when the concentrations of HVA and VMA were relatively higher. The mechanism of self-quenching processes involved in the Ru(bpy)(3)(2+)-HVA and -VMA ECL systems are proposed in this study.


Assuntos
Catecolaminas/metabolismo , Eletroquímica/métodos , Ácido Homovanílico/química , Medições Luminescentes/métodos , Compostos Organometálicos/química , Ácido Vanilmandélico/química , Soluções Tampão , Catecolaminas/química , Eletroquímica/instrumentação , Ácido Homovanílico/metabolismo , Medições Luminescentes/instrumentação , Oxirredução , Ácido Vanilmandélico/metabolismo
16.
Toxicol Ind Health ; 27(3): 235-41, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20937628

RESUMO

Ammonium perchlorate (AP), an oxidizer, has been used in solid propellants. Although AP exposure has been suspected as a risk factor for the development of pulmonary fibrosis, data are still inconclusive. To evaluate the pulmonary toxicity and the potential pulmonary fibrosis caused by occupational exposure to this compound, 25 male rabbits were randomly allocated into five groups to receive AP or bleomycin or saline by intratracheal injection. All rabbits were sacrificed and total RNA from the lungs was extracted. Expressions of types I and III collagens, transforming growth factor-ß(1) (TGF-ß(1)) and tumour necrosis factor-α (TNF-α) messenger RNA (mRNA) were measured by reverse transcription-polymerase chain reaction (RT-PCR). The expressions of type I and III collagen mRNA in low, moderate and high dose AP groups were significantly higher (p < 0.01 or p < 0.05) than that in the saline group. There was also a significant increased level of TGF-ß(1) and TNF-α mRNA in the three AP groups compared with saline control group (p < 0.01 or p < 0.05). These results reveal that AP can increase gene expressions of types I, III collagens, TGF-ß(1) and TNF-α in lung of rabbits exposed to AP. The overexpression of these biomarkers were considered as effective indicator linking to the development of pulmonary fibrosis and finally demonstrated that AP has potential to induce pulmonary fibrosis.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Percloratos/toxicidade , Fibrose Pulmonar/induzido quimicamente , Compostos de Amônio Quaternário/toxicidade , Animais , Biomarcadores/metabolismo , Bleomicina/toxicidade , Colágeno Tipo I/genética , Colágeno Tipo I/metabolismo , Colágeno Tipo III/genética , Colágeno Tipo III/metabolismo , Modelos Animais de Doenças , Expressão Gênica/efeitos dos fármacos , Marcadores Genéticos/efeitos dos fármacos , Marcadores Genéticos/genética , Intubação Intratraqueal , Masculino , Fibrose Pulmonar/genética , Fibrose Pulmonar/metabolismo , RNA Mensageiro/metabolismo , Coelhos , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
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