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1.
Environ Res ; 238(Pt 2): 117265, 2023 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-37775009

RESUMO

Thermal catalytic degradation of formaldehyde (HCHO) over manganese-based catalysts is garnering significant attention. In this study, both theoretical simulations and experimental methods were employed to elucidate the primary reaction pathways of HCHO on the MnO2(110) surface. Specifically, the effects of doping MnO2 with elements such as Fe, Ce, Ni, Co, and Cu on the HCHO oxidation properties were evaluated. Advanced characterization techniques, including X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), and X-ray photoelectron spectroscopy (XPS), were employed to discern the physical properties and chemical states of the active components on the catalyst surface. The comprehensive oxidation pathway of HCHO on the MnO2(110) surface includes O2 adsorption and dissociation, HCHO adsorption and dehydrogenation, CO2 desorption, H2O formation and desorption, oxygen vacancy supplementation, and other elementary reactions. The pivotal rate-determining step was identified as the hydrogen migration process, characterized by an energy barrier of 234.19 kJ mol-1. Notably, HCHOO and *CHOO emerged as crucial intermediates during the reaction. Among the doped catalysts, Fe-doped MnO2 outperformed its counterparts doped with Ce, Ni, Co, and Cu. The optimal degradation rate and selectivity were achieved at a molar ratio of Fe: Mn = 0.1. The superior performance of the Fe-doped MnO2 can be ascribed to its large specific surface area, conducive pore structure for HCHO molecular transport, rich surface-adsorbed oxygen species, and a significant presence of oxygen vacancies.


Assuntos
Manganês , Óxidos , Óxidos/química , Compostos de Manganês/química , Oxigênio/química , Catálise , Formaldeído/química
2.
Environ Pollut ; 332: 121742, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37121301

RESUMO

The decomposition of plant litter in soil changes soil nutrient content and plays an important role in regulating soil pH and availability of potentially toxic elements (PTEs). However, there remains limited studies on the mechanism under which litter influences the transport of PTEs in the process of ecological restoration. This study examined the effect of plant litter decomposition mediated reduction of iron and sulfur components on migration of PTEs from mercury-thallium mine waste. The results showed that the four kinds of litter alleviated the acidity of the waste, especially the Bpa and Tre litter. The nitro and nitroso groups produced by the decomposition of the litter were adsorbed onto the waste, thereby providing an electron transfer medium for iron reducing microorganisms, such as Geobacter. This promoted the reduction and release of Fe3+ to Fe2+ and reduced the electronegativity (El) value of waste. The reduced El promoted the adsorption of metal cations such as Hg and Tl to maintain electrical neutrality. However, it was not conducive to the adsorption of oxygen containing anions of As and Sb. An increase in litter resulted in an increase in reductivity of mercury-thallium mine waste. This maintained the reduction of Fe3+ to Fe2+ and changed or destroyed the structure of silicate minerals. PTEs, such as Tl, Hg, As, and Sb, were released, resulting in reductions in their residual fraction. However, the strong reduction conditions, especially the decomposition of Bpa, caused part of the released Hg(II) combining with S2- produced by the reduction of SO42- to form insoluble HgS, thereby reducing its migration. The findings could provide a theoretical basis to guide the situ-control and ecological restoration of PTEs in waste slag site.


Assuntos
Mercúrio , Poluentes do Solo , Tálio , Mercúrio/análise , Ferro , Monitoramento Ambiental/métodos , Enxofre , Plantas , Solo , Poluentes do Solo/análise
4.
Medicine (Baltimore) ; 100(51): e28384, 2021 Dec 23.
Artigo em Inglês | MEDLINE | ID: mdl-34941168

RESUMO

BACKGROUND: Prostatic hyperplasia is a physiological aging process in men. After transurethral resection of prostate (TURP), visceral pain is the main cause. The effective postoperative analgesia can reduce the occurrence of postoperative complications. This study mainly studied the analgesic effect of quadratus lumborum block (QLB) on TURP. METHODS: We divided 62 patients undergoing TURP into 2 groups using a random number table method (QLB 2 group and non-QLB [control] group). Patients in the QLB group underwent ultrasound-guided posterior QLB with 20 mL of 0.25% ropivacaine on each side, and those in the control group received only general anesthesia. The primary outcome for this study was the consumption analgesic pump during 0 to 24 hours. The secondary outcomes included the first pressing time of analgesic pump during 0 to 24 hours, the pain at rest and when coughing at 1, 4, 8, 12, and 24 hours post-operation as measured with a visual analogue scale for pain, length of the hospital stay, and complications (nausea and vomiting, dizziness, and abdominal distension). RESULTS: Patients in the QLB group presented less consumption, later first pressing time of analgesic pump during 0 to 24 hours after surgery lower visual analogue scale scores at 1, 4, 8, 12, and 24 hours postsurgery than those in the control group. Moreover, their mean length of hospital stay was shorter (P = .023), and they experienced less postoperative complications than the patients in the control group. CONCLUSIONS: Ultrasound-guided QLB in TURP provided a significant analgesic effect in our patients the first day after surgery. This analgesic model may improve the postoperative recovery after TURP.


Assuntos
Músculos Abdominais , Analgesia , Bloqueio Nervoso , Dor Pós-Operatória/prevenção & controle , Ressecção Transuretral da Próstata/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Anestésicos Locais , Humanos , Masculino , Pessoa de Meia-Idade , Bloqueio Nervoso/efeitos adversos , Dor Pós-Operatória/etiologia , Estudos Prospectivos , Ultrassonografia de Intervenção
5.
Acta Biochim Biophys Sin (Shanghai) ; 52(5): 527-535, 2020 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-32400862

RESUMO

Oral squamous cell carcinoma (OSCC) is a common type of malignant oral cancer that has a high recurrence rate. Voltage-gated sodium channel Nav1.5 was reported to be highly up-regulated in various types of cancers. However, the regulatory mechanism of Nav1.5 in cancers including OSCC still remains elusive. In this study, Nav1.5 was found to be highly expressed in OSCC tissues and cells. Through the analysis of clinical characteristics of patients, we found that the expression level of Nav1.5 was closely related to neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, tumor-node-metastasis stage, and lymph node metastasis. Moreover, we found that Nav1.5 mainly located on the cell membrane as well as cytoplasm and knockdown of Nav1.5 promoted cell apoptosis and decreased proliferation in OSCC. Transwell assay results showed that knockdown of Nav1.5 effectively suppressed the migration and invasion in OSCC. In addition, knockdown of Nav1.5 was found to inhibit the protein and mRNA expression levels of ß-catenin, cyclin D1, and c-Myc in the Wnt/ß-catenin signaling pathway. In summary, these results indicated that Nav1.5 may be involved in the progression of OSCC through the Wnt/ß-catenin signaling pathway.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Movimento Celular , Proliferação de Células , Neoplasias Bucais/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.5/metabolismo , Proteínas de Neoplasias/metabolismo , Via de Sinalização Wnt , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/patologia , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Bucais/genética , Neoplasias Bucais/patologia , Canal de Sódio Disparado por Voltagem NAV1.5/genética , Invasividade Neoplásica , Proteínas de Neoplasias/genética , beta Catenina/genética , beta Catenina/metabolismo
6.
Mol Cancer ; 18(1): 102, 2019 05 27.
Artigo em Inglês | MEDLINE | ID: mdl-31133028

RESUMO

There is growing evidence that regions of the genome that cannot encode proteins play an important role in diseases. These regions are usually transcribed into long non-coding RNAs (lncRNAs). LncRNAs, little or no coding potential, are defined as capped transcripts longer than 200 nucleotides. New sequencing technologies have shown that a large number of aberrantly expressed lncRNAs are associated with multiple cancer types and indicated they have emerged as an important class of pervasive genes during the development and progression of cancer. However, the underlying mechanism in cancer is still unknown. Therefore, it is necessary to elucidate the lncRNA function. Notably, many lncRNAs dysregulation are associated with Oral squamous cell carcinoma (OSCC) and affect various aspects of cellular homeostasis, including proliferation, survival, migration or genomic stability. This review expounds the up- or down-regulation of lncRNAs in OSCC and the molecular mechanisms by which lncRNAs perform their function in the malignant cell. Finally, the potential of lncRNAs as non-invasive biomarkers for OSCC diagnosis are also described. LncRNAs hold promise as prospective novel therapeutic targets, but more research is needed to gain a better understanding of their biologic function.


Assuntos
Carcinoma de Células Escamosas/genética , Redes Reguladoras de Genes , Neoplasias Bucais/genética , RNA Longo não Codificante/genética , Biomarcadores Tumorais/genética , Progressão da Doença , Regulação Neoplásica da Expressão Gênica , Humanos , Invasividade Neoplásica , Prognóstico
7.
Fitoterapia ; 123: 23-28, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28958956

RESUMO

A new chaetoglobosin, penochalasin K (1) bearing an unusual six-cyclic 6/5/6/5/6/13 fused ring system, along with the known analogues, chaetoglobosin C (2), penochalasin I (3), and chaetoglobosin A (4) were isolated from the solid culture of the mangrove endophytic fungus Penicillium chrysogenum V11. Their structures were elucidated by 1D, 2D NMR spectroscopic analysis and high resolution mass spectroscopic data. The absolute configuration of compound 1 was determined by comparing the theoretical and experimental electronic circular dichroism curves. Compound 1 displayed significant inhibitory activities against Colletotrichum gloeosporioides and Rhizoctonia solani (MICs=6.13, 12.26µM, respectively), which was better than those of carbendazim, and exhibited potent cytotoxicity against MDA-MB-435, SGC-7901 and A549 cells (IC50<10µM). An effective biomimetic transformation of chaetoglobosin C (2)/chaetoglobosin A (4) into penochalasin K (1)/penochalasin I (3) was developed, which provided a simple method for the semi-synthesis of chaetoglobosins with a six-cyclic 6/5/6/5/6/13 fused system formed by the connectivity of C-5 and C-2' from their corresponding epoxide analogues.


Assuntos
Alcaloides Indólicos/química , Penicillium chrysogenum/química , Antifúngicos/química , Antifúngicos/isolamento & purificação , Linhagem Celular Tumoral , Colletotrichum/efeitos dos fármacos , Endófitos/química , Humanos , Alcaloides Indólicos/isolamento & purificação , Testes de Sensibilidade Microbiana , Estrutura Molecular , Rhizoctonia/efeitos dos fármacos
8.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 51(3): 137-42, 2016 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-26980650

RESUMO

OBJECTIVE: To evaluate the expression of voltage-gated potassium channel Kv3.4 and to determine its significance in oral squamous cell carcinoma (OSCC) and precancerous lesions. METHODS: Immunohistochemical SP methods were performed to detect the expression of Kv3.4 at tissue level on 57 paraffin-embedded samples collected from Pathology Department of Anhui Province Stomatological Hospital during January 2013 to June 2014. The relationships between the expression of Kv3.4 and precancerous lesion and clinical pathologic factors of oral squamous cell carcinoma, such as pathologic classification, clinical stage and lymph node metastasis, were also analyzed. Totally 6 samples of normal oral mucosa tissue, 23 samples of OSCC and 13 samples of precancerous lesions were collected from the Department of Oral and Maxillofacial Surgery of The First Affiliated Hospital of Anhui Medical University during May 2014 to March 2015. Real-time quantitative PCR and Western blotting were used to detect the expression of Kv3.4 in these 42 samples at molecular and protein levels. RESULTS: Real-time quantitative PCR showed the relative expression quantity of Kv3.4 in normal oral mucosa, precancerous lesions, and OSCC tissues were 0.85±0.48, 3.50±2.51 and 18.48±7.70, respectively. The relative expression quantity of Kv3.4 in OSCC and precancerous lesions were higher than that in normal group, the differences were both statistically significant (P=0.002, P=0.029). The relative expression quantities of Kv3.4 protein in precancerous and OSCC tissues were 0.87±0.14 and 0.35±0.03 respectively by Western blotting, and both were higher than that in normal tissues (0.18±0.10). The differences were statistically significant (P=0.002). In 57 paraffin-embedded samples, the positive expression rates of Kv3.4 in normal, precancerous and OSCC tissues were 2/6, 13/18 and 95% (37/39), respectively. The differences were statistically significant(P<0.05). However, the expression of Kv3.4 did not show obvious correlation with patients' genders, presence of lymph node metastasis and clinical stages (P>0.05). CONCLUSIONS: The expression of Kv3.4 is positively correlated to OSCC's occurrence and development. Detection of the expression of Kv3.4 may be used for early diagnosis and prognostic judgment of oral squamous cell carcinoma and precancerous lesions.


Assuntos
Carcinoma de Células Escamosas/metabolismo , Neoplasias Bucais/metabolismo , Canais de Potássio de Abertura Dependente da Tensão da Membrana/metabolismo , Lesões Pré-Cancerosas/metabolismo , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Metástase Linfática , Masculino , Mucosa Bucal/metabolismo , Neoplasias Bucais/patologia , Lesões Pré-Cancerosas/patologia , Prognóstico , Fatores Sexuais
9.
Zhonghua Kou Qiang Yi Xue Za Zhi ; 49(2): 95-100, 2014 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-24731421

RESUMO

OBJECTIVE: To investigate the relationship between pulpitis pain and voltage-gated sodium channel (Nav1.9) by detecting the expression of Nav1.9 at different time points of the rat pulpal lesion model. METHODS: Thirty-six SD pulpal lesions rat models were divided into three experimental groups, 1 d (n = 12), 3 d (n = 12) and 5 d group(n = 12).Normal SD rats served as control(n = 12). Tumor necrosis factor-α (TNF-α) and Nav1.9 mRNA expressions were evaluated by reverse transcription PCR (RT-PCR) .Nav1.9 protein expressions were analyzed by enzyme-linked immunosorbent assay (ELISA) and Western blotting. RESULTS: The expression of TNF-α in the experimental group (1 d:0.514 ± 0.098, 3 d:0.739 ± 0.104, 5 d:1.238 ± 0.082) was higher than those in the control group (0.147 ± 0.016) (P < 0.01). Nav1.9 mRNA was up-regulated markedly in experimental groups (1 d: 0.296 ± 0.038, 3 d:0.409 ± 0.013, 5 d: 0.487 ± 0.028) , compare with control group (0.223 ± 0.020) (P < 0.05). The ELISA results revealed that the level of Nav1.9 in control pulp tissue was (4.013 ± 0.292) µg/L, in painful pulp tissue of 1 d group was (5.143 ± 0.101) µg/L, in painful pulp tissue of 3 d group was (5.835 ± 0.088) µg/L and in painful pulp tissue of 5 d group was (6.307 ± 0.137) µg/L (P < 0.05). Western blotting showed the expression of Nav1.9 in experimental groups (1 d: 0.106 ± 0.007, 3 d:0.170 ± 0.013, 5 d:0.238 ± 0.004) was up-regulated significantly compared with control group (0.073 ± 0.004)(P < 0.05). CONCLUSIONS: The level of Nav1.9 had a significant increase in painful pulp tissue. Moreover, with the degree of pain aggravation, the expression of Nav1.9 increased in pulp tissue.It suggests that Nav1.9 may play an important role in the development of pulpitis pain.


Assuntos
Polpa Dentária/metabolismo , Canal de Sódio Disparado por Voltagem NAV1.9/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Animais , Western Blotting , Polpa Dentária/patologia , Dor , Pulpite , RNA Mensageiro , Ratos , Regulação para Cima
10.
Chin J Integr Med ; 19(8): 636-40, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23893135

RESUMO

Chinese medicines (CMs) are increasingly being used for the treatment of tumors because of their unique advantages. The induction of tumor cell apoptosis is an important method of tumor treatment. Caspase-3 is a member of the caspase (cysteine aspartic proteinases) family of enzymes, which are the major inducers of apoptosis. Caspase-3 activity is often measured in the context of research into anti-tumor drugs that target apoptosis. Many studies have shown that CMs upregulate the expression of caspase-3 in tumor cells via extrinsic and/or intrinsic pathways, removing endogenous suppression of apoptosis and promoting tumor cell death. Therefore, several CMs fulfill the criteria for anti-tumor drugs. In this paper, we review the efficacy of 14 Chinese herbal medicines, across a wide range applications, and discuss their effects on caspase-3 activity in tumor cells.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Caspase 3/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Neoplasias/metabolismo , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Apoptose/fisiologia , Medicamentos de Ervas Chinesas/uso terapêutico , Humanos , Neoplasias/tratamento farmacológico , Plantas Medicinais/fisiologia , Transdução de Sinais/efeitos dos fármacos
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