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1.
BMC Cancer ; 23(1): 622, 2023 Jul 04.
Artigo em Inglês | MEDLINE | ID: mdl-37403054

RESUMO

BACKGROUND: Lymph node metastasis (LNM) is an important factor affecting endometrial cancer (EC) prognosis. Current controversy exists as to how to accurately assess the risk of lymphatic metastasis. Metabolic syndrome has been considered a risk factor for endometrial cancer, yet its effect on LNM remains elusive. We developed a nomogram integrating metabolic syndrome indicators with other crucial variables to predict lymph node metastasis in endometrial cancer. METHODS: This study is based on patients diagnosed with EC in Peking University People's Hospital between January 2004 and December 2020. A total of 1076 patients diagnosed with EC and who underwent staging surgery were divided into training and validation cohorts according to the ratio of 2:1. Univariate and multivariate logistic regression analyses were used to determine the significant predictive factors. RESULTS: The prediction nomogram included MSR, positive peritoneal cytology, lymph vascular space invasion, endometrioid histological type, tumor size > = 2 cm, myometrial invasion > = 50%, cervical stromal invasion, and tumor grade. In the training group, the area under the curve (AUC) of the nomogram and Mayo criteria were 0.85 (95% CI: 0.81-0.90) and 0.77 (95% CI: 0.77-0.83), respectively (P < 0.01). In the validation group (N = 359), the AUC was 0.87 (95% CI: 0.82-0.93) and 0.80 (95% CI: 0.74-0.87) for the nomogram and the Mayo criteria, respectively (P = 0.01). Calibration plots revealed the satisfactory performance of the nomogram. Decision curve analysis showed a positive net benefit of this nomogram, which indicated clinical value. CONCLUSION: This model may promote risk stratification and individualized treatment, thus improving the prognosis.


Assuntos
Neoplasias do Endométrio , Síndrome Metabólica , Feminino , Humanos , Nomogramas , Metástase Linfática/patologia , Síndrome Metabólica/complicações , Estudos Retrospectivos , Neoplasias do Endométrio/cirurgia , Neoplasias do Endométrio/patologia , Linfonodos/patologia
2.
World J Clin Cases ; 10(19): 6702-6709, 2022 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-35979309

RESUMO

BACKGROUND: Endometrial cancer (EC) is a common gynecological malignancy, but metastasis to the abdominal wall is extremely rare. Therefore, an appropriate treatment approach for large metastatic lesions with infection remains a great challenge. CASE SUMMARY: We report the case of a 65-year-old woman who developed abdominal metastasis of endometrioid adenocarcinoma, as defined by International Obstetrics and Gynecology stage II, in which the lesion was complicated by infection. A right hemicolectomy was performed for colon metastasis in relation to her initial gynecological cancer 3 years ago. When admitted to our department, a complete resection of the giant abdominal wall lesion was performed, and a Bard composite mesh was used to reconstruct the abdominal wall. A local flap was used to close the resultant large defect in the external covering of the abdomen. The patient underwent chemotherapy following cytoreductive surgery. Pathology revealed metastasis of EC, and molecular subtyping showed copy number high of TP53 mutation, implying a poor prognosis. CONCLUSION: When EC patients develop giant abdominal wall metastasis, a plastic surgeon should be included before contemplating resection of tumors.

3.
BMJ Open ; 11(10): e050387, 2021 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-34645665

RESUMO

OBJECTIVES: Laryngeal cancer is the most prevalent entity of head and neck cancer. Knowing the trends of incidence and mortality of laryngeal cancer is important for the reduction in related disease burden. DESIGN: Population-based observational study. MAIN OUTCOMES AND MEASURES: The incidence and mortality data of laryngeal cancer were retrieved from the Global Burden of Disease study 2017 online database. The estimated average percentage change was used to quantify the trends of laryngeal cancer incidence and mortality at the global, regional and national levels. RESULTS: Globally, the numbers of incident cases and deaths due to laryngeal cancer increased 58.7% and 33.9%, respectively, from 1990 to 2017. However, the overall age-standardised incidence rate (ASIR) and age-standardised mortality rate decreased by 0.99% (95% CI 0.83% to 1.14%) and 1.62% (95% CI 1.50% to 1.74%) per year, respectively. These decreases were ubiquitous worldwide. However, unfavourable trends in the ASIR of laryngeal cancer were also observed in a total of 51 developing countries. CONCLUSIONS: The incidence and mortality rates of laryngeal cancer have significantly decreased at the global level and in most countries over the past three decades. The regions that showed an increasing incidence trend deserve more attention.


Assuntos
Neoplasias Laríngeas , Carga Global da Doença , Saúde Global , Humanos , Incidência , Neoplasias Laríngeas/epidemiologia , Mortalidade , Fatores de Risco
4.
BMC Cancer ; 21(1): 1082, 2021 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-34620148

RESUMO

BACKGROUND: Alcohol consumption and smoking are the leading risk factors for laryngeal cancer (LC). Understanding the variations in disease burden of LC attributable to alcohol use and smoking is critical for LC prevention. METHODS: Disease burden data of LC were retrieved from the Global Burden of Disease Study 2019. We used estimated average percentage change (EAPC) to measure the temporal trends of the age-standardized mortality rate (ASMR) of LC. RESULTS: Globally, while the ASMR of LC decreased by 1.49% (95% CI, 1.41-1.57%) per year between 1990 and 2019, the number of deaths from LC has increased 41.0% to 123.4 thousand in 2019. In 2019, 19.4 and 63.5% of total LC-related deaths were attributable to alcohol use and smoking worldwide, respectively. The ASMR of alcohol- and smoking-related LC decreased by 1.78 and 1.93% per year, whereas the corresponding death number has increased 29.2 and 25.1% during this period, respectively. The decreasing trend was more pronounced in developed countries. In some developing countries, such as Guinea and Mongolia, the LC mortality has shown an unfavorable trend. CONCLUSION: The ubiquitous decrease in LC mortality was largely attributed to the smoking control and highlighted the importance of smoking control policies. However, the disease burden of LC remained in increase and more effective strategies are needed to combat the global increase of alcohol consumption.


Assuntos
Consumo de Bebidas Alcoólicas/mortalidade , Efeitos Psicossociais da Doença , Saúde Global/estatística & dados numéricos , Neoplasias Laríngeas/mortalidade , Fumar/mortalidade , Consumo de Bebidas Alcoólicas/efeitos adversos , Causas de Morte , Intervalos de Confiança , Países Desenvolvidos/estatística & dados numéricos , Países em Desenvolvimento/estatística & dados numéricos , Feminino , Humanos , Neoplasias Laríngeas/etiologia , Masculino , Mortalidade/tendências , Fatores de Risco , Fumar/efeitos adversos , Fatores de Tempo , Fumar Tabaco/efeitos adversos
5.
Curr HIV Res ; 18(3): 219-226, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32294041

RESUMO

BACKGROUND: In China, although quite a few bold programmes have been made for HIV/AIDS, the epidemic has still shown an increasing trend. OBJECTIVES: The study was aimed to investigate the characteristics of new HIV/AIDS and the major factors of false positives (FP) for HIV testing. METHODS: A retrospective review was performed in a teaching hospital in Xi'an between 2013 and 2018. The overall characteristics and trends of new HIV/AIDS were described. Moreover, the major factors of FP were determined by the Pareto analysis. RESULTS: A total of 469 new HIV/AIDS were diagnosed, with an increasing prevalence of the new HIV/AIDS from 0.0626% (41/65503) in 2013 to 0.0827% (115/139046) in 2018. Of them, the majority occurred in the males (88.50%), people aged 21-50 years (76.97%), migrants (60.98%), and sexual contact route (88.70%). There was a rapid increase in the annual number of new HIV/AIDS and increasing trends in groups of young individuals, students, and homosexual mode; however, a downward trend in the percentage of injecting drug use was also observed. Over 50 years old and patients from oncology, obstetrics, hepatobiliary surgery, nephrology, cardiology, and infectious disease constituted the major factors of FP. CONCLUSION: The HIV/AIDS epidemic in Xi'an is still evolving, therefore, effective strategies, appropriate education and scaling up HIV testing should be developed. In addition, old adults and specific departments were associated with FP.


Assuntos
Erros de Diagnóstico/estatística & dados numéricos , Epidemias , Infecções por HIV/diagnóstico , Infecções por HIV/epidemiologia , HIV/patogenicidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , China/epidemiologia , Reações Falso-Positivas , Feminino , HIV/crescimento & desenvolvimento , Infecções por HIV/transmissão , Teste de HIV/métodos , Homossexualidade Masculina , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Prevalência , Estudos Retrospectivos , Sexo sem Proteção/psicologia , Sexo sem Proteção/estatística & dados numéricos
6.
Int. j. morphol ; 38(2): 247-251, abr. 2020. tab, graf
Artigo em Inglês | LILACS | ID: biblio-1056430

RESUMO

Nine tumor and various potential biomarkers were measured and combined the information to diagnose disease, all patients accepted fiber bronchoscopy brush liquid based cytologyand histopathology examination in order to reliably detect lung cancer. The samples from 314 Chinese lung cancer patients were obtained and CK5/6, P63, P40, CK7, TTF-1, NapsinA CD56, Syn and CgA were measured with the immunohistochemical SP method and analyzed correlation of the expression of these markers with pathological and clinical features of squamous cell carcinoma, adenocarcinoma, and small cell lung carcinoma. Squamous cell carcinoma, adenocarcinoma and small cell carcinoma were 61 cases, 114 cases and 139 cases,CK5/6 and P63 expression were more frequent in squamous cell carcinoma, with sensitivity and specificity of 77.05 % and 96.44 %, 83.61 % and 88.93 %,and compared with adenocarcinoma and small cell carcinoma difference was statistically significant (P<0.05), The incidences of a positive P40 expression were 100 % in squamous cell carcinoma, with specificity of 98.81 %.CK7, TTF-1 and NapsinA expression were more frequent in adenocarcinoma, with sensitivity and specificity of 85.09 % and 78.69 %, 79.82 % and 93.44 %, 56.14 % and 95.08 %, and compared with squamous cell carcinoma and small cell carcinoma difference was statistically significant (P<0.05). TTF-1, Syn, CgA and CD56 expression were more frequent in adenocarcinoma, with sensitivity and specificity of 86.33 % and 93.44 %, 89.21 % and 98.36 %, 74.10 % and 100 %, 96.40 % and 96.72 %. The combined detection of CK5/6, P63 and P40 were more useful and specific in differentiating squamous cell carcinoma. CK7, TTF-1 and NapsinA were more useful and specific in differentiating lung adenocarcinoma. The impaired CD56, TTF-1, Syn and CgA reflects the progression of small cell lung cancer.


Se midieron tumores y utilizaron nueve biomarcadores potenciales y se analizó la información para diagnosticar la enfermedad. A todos los pacientes se les realizó citología en líquido con broncoscopía de fibra y examen histopatológico para detectar de manera confiable el cáncer pulmonar. Se obtuvieron muestras de 314 pacientes chinos con cáncer de pulmón y CK5 / 6, P63, P40, CK7, TTF-1, Napsina A, CD56, Syn y CgA se midieron a través de histoquímica SP y analizaron la correlación de la expresión de estos marcadores con características patológicas y clínicas de carcinoma de células escamosas, adenocarcinoma y carcinoma de células pequeñas en el cáncer de pulmón. El carcinoma de células escamosas, el adenocarcinoma y el carcinoma de células pequeñas fueron 61 casos, 114 casos y 139 casos, respectivamente, la expresión de CK5 / 6 y P63 fueron más frecuentes en el carcinoma de células escamosas, con una sensibilidad y especificidad del 77,05 % y 96,44 %, 83,61 % y 88,93 %, y en comparación con el adenocarcinoma y el carcinoma de células pequeñas, la diferencia fue estadísticamente significativa (P <0,05). La incidencia de ap la expresión positiva P40 fue del 100 % en el carcinoma de células escamosas, con una especificidad del 98,81 %. La expresión de CK7, TTF-1 y NapsinA fueron más frecuentes en el adenocarcinoma, con una sensibilidad y especificidad del 85,09 % y 78,69 %, 79,82 % y 93,44 %, 56,14 % y 95,08 %, y en comparación con el carcinoma de células escamosas y la diferencia de carcinoma de células pequeñas fue estadísticamente significativa (P <0,05) .TTF-1, Syn, CgA y la expresión de CD56 fueron más frecuentes en adenocarcinoma, con sensibilidad y especificidad de 86.33 % y 93.44 %, 89.21 % y 98.36 %, 74.10 % y 100 %, 96.40 % y 96.72 %. La detección combinada de CK5 / 6, P63 y P40 fue más útil y específica en la diferenciación del carcinoma de células escamosas. CK7, TTF-1 y NapsinA fueron más útiles y específicos para diferenciar el adenocarcinoma de pulmón. El deterioro de CD56, TTF-1, Syn y CgA refleja la progresión del cáncer de pulmón de células pequeñas.


Assuntos
Humanos , Carcinoma/metabolismo , Carcinoma/patologia , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Fragmentos de Peptídeos/metabolismo , Fatores de Transcrição/metabolismo , Imuno-Histoquímica , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Adenocarcinoma/metabolismo , Adenocarcinoma/patologia , Biomarcadores Tumorais/metabolismo , Ácido Aspártico Endopeptidases/metabolismo , Sensibilidade e Especificidade , Carcinoma de Células Pequenas/metabolismo , Carcinoma de Células Pequenas/patologia , Antígeno CD56/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Queratinas Tipo II/metabolismo , Queratina-7/metabolismo , Fator Nuclear 1 de Tireoide/metabolismo
7.
Reprod Sci ; 26(11): 1439-1448, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-30599813

RESUMO

To some extent, the use of metformin may improve endometrial receptivity and pregnancy outcomes of women with polycystic ovarian syndrome (PCOS) undergoing in vitro fertilization/intracytoplasmic sperm injection. However, the mechanism is not well-known. The endometrium of metformin-treated group (metformin-treated patients with PCOS) and the control group (non-metformin-treated patients with PCOS) were analyzed for the expression of homeobox A10 (HOXA10) and integrin beta-3 (ITGB3) and differential micro RNA (miRNA) expression profiles. On this basis, miRDB and Target Scan databases were used to predict and screen out that miR-491-3p and miR-1910-3p may target HOXA10 and ITGB3. Furthermore, we verified the effects of metformin on the expression of HOXA10 and ITGB3, and regulatory effects of miR-1910-3p and miR-491-3p on HOXA10 and ITGB3 using Ishikawa cell line. Metformin induced a significant dose-dependent upregulation of HOXA10 and ITGB3. The results from the microarray analyses showed there were 40 differentially expressed miRNAs between the 2 groups. Among them, miR-1910-3p and miR-491-3p were the 2 significantly downregulated miRNAs. Bioinformatics prediction indicated that HOXA10 and ITGB3 are potential target genes for miR-1910-3p and miR-491-3p. In Ishikawa cells transfected with miR-491-3p mimics, the expression of HOXA10 and ITGB3 on both messenger RNA (mRNA) and protein level were lower than those in control group (P < .001). Also, the expression of HOXA10 mRNA and protein was lower in Ishikawa cells transfected with miR-1910-3p mimics (P < .001). However, no significant changes in ITGB3 levels were observed in cells transfected with miR-1910-3p mimics (P > .05). Metformin likely improves endometrial receptivity through downregulating the expression of miR-491-3p and miR-1910-3p, thereby increasing the expression of HOXA10 and ITGB3 in the endometrium of PCOS women.


Assuntos
Fertilização in vitro/métodos , Metformina/uso terapêutico , MicroRNAs/biossíntese , Síndrome do Ovário Policístico/tratamento farmacológico , Síndrome do Ovário Policístico/metabolismo , Injeções de Esperma Intracitoplásmicas/métodos , Adulto , Implantação do Embrião/efeitos dos fármacos , Implantação do Embrião/fisiologia , Endométrio/efeitos dos fármacos , Endométrio/metabolismo , Feminino , Expressão Gênica , Marcadores Genéticos/efeitos dos fármacos , Marcadores Genéticos/fisiologia , Proteínas Homeobox A10/biossíntese , Proteínas Homeobox A10/genética , Humanos , Infertilidade Feminina/tratamento farmacológico , Infertilidade Feminina/genética , Infertilidade Feminina/metabolismo , Integrina beta3/biossíntese , Integrina beta3/genética , Metformina/farmacologia , MicroRNAs/genética , Recuperação de Oócitos/métodos , Síndrome do Ovário Policístico/genética
8.
Dev Comp Immunol ; 51(1): 134-40, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-25819083

RESUMO

The transforming growth factor ß (TGF-ß) superfamily plays critical roles in tumor suppression, cell proliferation and differentiation, tissue morphogenesis, lineage determination, cell migration and apoptosis. Recently, TGF-ß1, one important member of TGF-ß superfamily, is suggested as an immune regulator in the teleost. In this study, we cloned the cDNAs of TGF-ß1 and its receptors, TßR I and TßR II (including three isoforms) from tilapia (Genbank accession numbers: KP754231- KP754235). A tissue distribution profile analysis indicated that TGF-ß1 was highly expressed in the head kidney, gill, spleen, kidney and PBLs (peripheral blood leukocytes); TßR I only showed considerable expression in the liver; and TßR II-2 was highly expressed in the kidney, gill, liver, head kidney and heart. We determined that the mRNA expressions of TGF-ß and TßR I /TßR II-2 were significantly increased in tilapia head kidney and spleen leukocytes by the stimulation of Lipopolysaccharide (LPS) or Poly I: C. We also examined their expressions in the spleen and head kidney of tilapia after IP injection of streptococcus agalactiae. The results showed that the mRNA expressions of these three genes all increased in the head kidney as early as 6 h post infection, and in the spleen 3 d post infection. In addition, the protein level of TGF-ß1 was also up-regulated in the head kidney and the spleen after infection. Taken together, our data indicate that the TGF-ß1-TßR I /TßR II-2 system functions potentially in tilapia immune system.


Assuntos
Rim Cefálico/fisiologia , Receptores de Fatores de Crescimento Transformadores beta/metabolismo , Baço/fisiologia , Infecções Estreptocócicas/imunologia , Streptococcus agalactiae/imunologia , Tilápia/imunologia , Fator de Crescimento Transformador beta1/imunologia , Sequência de Aminoácidos , Animais , Sequência de Bases , Clonagem Molecular , Regulação da Expressão Gênica , Rim Cefálico/microbiologia , Imunidade , Dados de Sequência Molecular , Isoformas de Proteínas/genética , Receptores de Fatores de Crescimento Transformadores beta/genética , Baço/microbiologia , Transcriptoma
9.
Dev Comp Immunol ; 46(2): 448-60, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24950416

RESUMO

FasL is the most extensively studied apoptosis ligand. In 2000, tilapia FasL was identified using anti-human FasL monoclonal antibody by Evans's research group. Recently, a tilapia FasL-like protein of smaller molecule weight was predicted in Genbank (XM_003445156.2). Based on several clues drawn from previous studies, we cast doubt on the authenticity of the formerly identified tilapia FasL. Conversely, using reverse transcription polymerase chain reaction (RT-PCR), the existence of the predicted FasL-like was verified at the mRNA level (The Genbank accession number of the FasL mRNA sequence we cloned is KM008610). Through multiple alignments, this FasL-like protein was found to be highly similar to the FasL of the Japanese flounder. Moreover, we artificially expressed the functional region of the predicted protein and later confirmed its apoptosis-inducing activity using a methyl thiazolyl tetrazolium (MTT) assay, Annexin-V/Propidium iodide (PI) double staining, and DNA fragment detection. Supported by these evidences, we suggest that the predicted protein is the authentic tilapia FasL. To advance this research further, tilapia FasL mRNA and its protein across different tissues were quantified. High expression levels were identified in the tilapia immune system and sites where active cell turnover conservatively occurs. In this regard, FasL may assume an active role in the immune system and cell homeostasis maintenance in tilapia, similar to that shown in other species. In addition, because the distribution pattern of FasL mRNA did not synchronize with that of the protein, post-transcriptional expression regulation is suggested. Such regulation may be dominated by potential adenylate- and uridylate-rich elements (AREs) featuring AUUUA repeats found in the 3' untranslated region (UTR) of tilapia FasL mRNA.


Assuntos
Proteína Ligante Fas/genética , Proteínas de Peixes/genética , Tilápia/genética , Sequência de Aminoácidos , Animais , Sequência de Bases , Sequência Conservada , Proteína Ligante Fas/biossíntese , Proteínas de Peixes/biossíntese , Expressão Gênica , Células HeLa , Humanos , Dados de Sequência Molecular , Especificidade de Órgãos , Filogenia , Tilápia/imunologia , Tilápia/metabolismo
10.
Brain Behav Immun ; 35: 96-106, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24041578

RESUMO

Colitis is a group of inflammatory and auto-immune disorders that affect the tissue lining of the gastrointestinal (GI) system. Studies of chemically-induced animal models of colitis have indicated that nociceptive afferents or neuropeptides have differing effects on GI inflammation. However, the molecular mechanisms involved in visceral pain and the role of visceral sensory afferents involved in the modulation of colitis remains unclear. A previous study demonstrated that Runx1, a Runt domain transcription factor, is restricted to nociceptors. In these neurons, Runx1 regulates the expression of numerous ion channels and receptors, controlling the lamina-specific innervation patterns of nociceptive afferents in the spinal cord. Moreover, mice that lack Runx1 exhibit specific defects in thermal and neuropathic pain. To examine the function of Runx1 in visceral nociception, we employed double-transgenic mice (WntCre: Runx1(F/F)), in which the expression of Runx1 was specifically disrupted in the sensory neurons. To determine the role of Runx1 in visceral pain sensation, the WntCre: Runx1(F/F) mice and their control littermates (Runx1(F/F)) were treated using dextran sodium sulfate (DSS) to induce colitis. The results indicated that disrupted Runx1 in the sensory afferents resulted in: (1) impairment of the visceral pain sensation in murine DSS-induced colitis; (2) exacerbating the phenotypes in murine DSS-induced colitis; (3) a differential effect on the production of pro- and anti-inflammatory cytokines in the colon tissues isolated from mice treated using DSS and 2,4,6-trinitrobenzene sulfonic acid (TNBS)-induced colitis; and (4) alteration of the distribution of lymphocytes and mast cells in mucosa. These results show that the function of Runx1 in sensory afferents is vital for modulating visceral pain and the neuro-immune axis.


Assuntos
Colite/fisiopatologia , Subunidade alfa 2 de Fator de Ligação ao Core/fisiologia , Neurônios Aferentes/fisiologia , Nociceptividade/fisiologia , Dor Visceral/fisiopatologia , Animais , Colite/induzido quimicamente , Colite/complicações , Subunidade alfa 2 de Fator de Ligação ao Core/deficiência , Sulfato de Dextrana/farmacologia , Modelos Animais de Doenças , Ensaio de Imunoadsorção Enzimática , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Reação em Cadeia da Polimerase , Células Receptoras Sensoriais/fisiologia , Dor Visceral/etiologia
11.
J Biosci Bioeng ; 117(3): 379-82, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24119486

RESUMO

A gas chromatography-mass spectrometry method for quantification of polyhydroxyalkanoates (PHAs), containing 4-carbon to 16-carbon monomers, even in the absence of standards, was developed. Strong linear correlations existed between PHA carbon number and retention time/response factor (R(2) ≥ 0.987). Based on the correlations, high recovery values, between 100.5% and 114.3%, were obtained for PHA polymers.


Assuntos
Carbono/química , Cromatografia Gasosa-Espectrometria de Massas/métodos , Poli-Hidroxialcanoatos/análise , Bactérias/química
12.
J Phys Chem B ; 117(18): 5606-13, 2013 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-23574310

RESUMO

In this paper, we obtained various water-soluble polymer functionalized graphene in dimethyl sulfoxide under ultrasonication. The atomic force microscope analysis and control experiment shows the water-soluble polymer is the crucial part to help solvent molecules separate interlayer. Such polymer/graphene exhibits high conductivity and tunable surface property, as confirmed by the selected area electron diffraction and Raman and electrochemical impedance spectroscopy. As a result, a catalyst based on polyvinyl pyrrolidone (PVP)/graphene shows better methanol oxidation performance than that based on PVP/reduced graphene oxide. By changing to another polymer, poly(4-vinylpyridine)/graphene shows a stable and reversible response to pH, and demonstrates its potential for sensor application.


Assuntos
Grafite/química , Polivinil/química , Povidona/química , Água/química , Catálise , Dimetil Sulfóxido/química , Concentração de Íons de Hidrogênio , Solubilidade , Ultrassom
13.
Sci Total Environ ; 445-446: 281-98, 2013 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-23337605

RESUMO

Cytostatic drugs have been widely used for chemotherapy for decades. However, many of them have been categorized as carcinogenic, mutagenic and teratogenic compounds, triggering widespread concerns about their occupational exposure and ecotoxicological risks to the environment. This review focuses on trace presence, fate and ecotoxicity of various cytostatic compounds in the environment, with an emphasis on the major sources contributing to their environmental concentrations. Past records have documented findings mainly on hospital effluents though little effort has been directed to household discharges. There is also a lack in physico-chemical data for forecasting the chemodynamics of cytostatics in natural waters along with its human metabolites and environmental transformation products. In this light, obtaining comprehensive ecotoxicity data is becoming pressingly crucial to determine their actual impacts on the ecosystem. Literature review also reveals urinary excretion as a major contributor to various cytostatic residues appeared in the water cycle. As such, engaging urine source-separation as a part of control strategy holds a rosy prospect of addressing the "emerging" contamination issue. State-of-the-art treatment technologies should be incorporated to further remove cytostatic residues from the source-separating urine stream. The benefits, limitations and trends of development in this domain are covered for membrane bio-reactor, reverse/forward osmosis and advanced oxidation processes. Despite the respective seeming advantages of source separation and treatment technology, a combined strategy may cost-effectively prevent the cytostatic residues from seeping into the environment. However, the combination calls for further evaluation on the associated technological, social-economic and administrative issues at hand.


Assuntos
Citostáticos/análise , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Citostáticos/química , Ecossistema , Exposição Ambiental , Filtração , Humanos , Oxirredução , Medição de Risco , Espectinomicina , Poluentes Químicos da Água/química
14.
Biosens Bioelectron ; 26(5): 2142-6, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20947329

RESUMO

This study reports the fabrication of a new membrane electrode assembly by using stainless steel mesh (SSM) as raw material and its effectiveness as gas diffusion electrode (GDE) for electrochemical oxygen reduction in microbial fuel cell (MFC). Based on feeding glucose (0.5 g L(-1)) substrate to a single-chambered MFC, power generation using SSM-based GDE was increased with the decrease of polytetrafluoroethylene (PTFE) content applied during fabrication, reaching the optimum power density of 951.6 mW m(-2) at 20% PTFE. Repeatable cell voltage of 0.51 V (external resistance of 400 Ω) and maximum power density of 951.6 mW m(-2) produced for the MFC with SSM-based GDE are comparable to that of 0.52 V and 972.6 mW m(-2), respectively obtained for the MFC containing typical carbon cloth (CC)-made GDE. Besides, Coulombic efficiency (CE) is found higher for GDE (SSM or CC) with membrane assembly than without, which results preliminarily from the mitigation of Coulombic loss being associated with oxygen diffusion and substrate crossover. This study demonstrates that with its good electrical conductivity and much lower cost, the SSM-made GDE suggests a promising alternative as efficient and more economically viable material to conventional typical carbon for power production from biomass in MFC.


Assuntos
Fontes de Energia Bioelétrica/microbiologia , Fontes de Energia Elétrica/microbiologia , Eletrodos/microbiologia , Aço Inoxidável/química , Difusão , Desenho de Equipamento , Análise de Falha de Equipamento , Gases/química
15.
J Hazard Mater ; 184(1-3): 547-554, 2010 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-20833468

RESUMO

An enhanced electrokinetic process for the removal of cadmium (Cd), nickel (Ni) and zinc (Zn) from contaminated soils was performed. The efficiency of the chelate agents nitrilotriacetic acid (NTA), diethylenetriaminepentaacetic acid (DTPA) and diaminocycloexanetetraacetic acid (DCyTA) was examined under constant potential gradient (1.23 V/cm). The results showed that chelates were effective in desorbing metals at a high pH, with metal-chelate anion complexes migrating towards the anode. At low pH, metals existing as dissolved cations migrated towards the cathode. In such conflicting directions, the metals accumulated in the middle of the cell. Speciation of the metals during the electrokinetic experiments was performed to provide an understanding of the distribution of the Cd, Ni and Zn. The results of sequential extraction analysis revealed that the forms of the metals could be altered from one fraction to another due to the variation of physico-chemical conditions throughout the cell, such as pH, redox potential and the chemistry of the electrolyte solution during the electrokinetic treatment. It was found that binding forms of metals were changed from the difficult type to easier extraction type.


Assuntos
Cádmio/isolamento & purificação , Eletroquímica/métodos , Recuperação e Remediação Ambiental/métodos , Níquel/isolamento & purificação , Poluentes do Solo/isolamento & purificação , Zinco/isolamento & purificação , Concentração de Íons de Hidrogênio , Oxirredução
16.
Bioresour Technol ; 101(24): 9550-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20696576

RESUMO

Caproate always appears during fermentative H(2) production but its formation was not well explained. It possibly results from the secondary fermentation of ethanol and acetate or butyrate by some special species like Clostridium kluyveri. This study attempts to elucidate caproate formation during the fermentation H(2) production by using C. kluyveri as an example and evaluating several possible pathways of caproate formation. A detailed energetic analysis of the empirical data of an H(2)-producing reactor demonstrated that caproate can be formed from two substrates, either ethanol and acetate or ethanol and butyrate. The analysis showed that at least 5 mol ethanol per mole reaction was essential to support caproate formation under the experimental condition. The analysis also indicated that the secondary fermentation by C. kluyveri might be another pathway to spontaneously produce H(2), butyrate, and acetate in addition to the butyrate-acetate pathway. Co-production of caproate and H(2) from ethanol was thermodynamically feasible and contributed to at least 10-20% of total H(2) production in the reactor studied. It is also clarified that caproate formation is hydrogenogenic rather than hydrogenotrophic.


Assuntos
Caproatos/metabolismo , Clostridium/citologia , Fermentação/fisiologia , Hidrogênio/metabolismo , Acetatos/metabolismo , Trifosfato de Adenosina/metabolismo , Reatores Biológicos/microbiologia , Butiratos/metabolismo , Clostridium/metabolismo , Conservação de Recursos Energéticos , Etanol/metabolismo , Solubilidade , Termodinâmica , Valeratos/metabolismo
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