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1.
Nature ; 606(7914): 511-515, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35417651

RESUMO

The recycling of aluminium scrap today utilizing a remelting technique downgrades the quality of the aluminium, and the final sink of this downgraded recycled aluminium is aluminium casting alloys1-9. The predicted increase in demand for high-grade aluminium as consumers choose battery-powered electric vehicles over internal combustion engine vehicles is expected to be accompanied by a drop in the demand for low-grade recycled aluminium, which is mostly used in the production of internal combustion engines2,7,10,11. To meet the demand for high-grade aluminium in the future, a new aluminium recycling method capable of upgrading scrap to a level similar to that of primary aluminium is required2-4,7,11. Here we propose a solid-state electrolysis (SSE) process using molten salts for upcycling aluminium scrap. The SSE produces aluminium with a purity comparable to that of primary aluminium from aluminium casting alloys. Moreover, the energy consumption of the industrial SSE is estimated to be less than half that of the primary aluminium production process. By effectively recycling aluminium scrap, it could be possible to consistently meet demand for high-grade aluminium. True sustainability in the aluminium cycle is foreseeable with the use of this efficient, low-energy-consuming process.

2.
J Dermatol ; 48(10): 1474-1481, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34212423

RESUMO

Onychomycosis with longitudinal spikes in the nail plate has been reported to be refractory to oral drugs as with dermatophytoma. We evaluated the efficacy of 10% efinaconazole solution in the treatment of onychomycosis with longitudinal spikes. Of the 223 subjects who were enrolled in a previous study, a post-hoc analysis of 82 subjects with longitudinal spikes was performed in this study. The opacity ratio of longitudinal spikes was decreased over time from 8.1 to 0.9 at the final assessment. In addition, the longitudinal spike disappearance rate increased early after the application to 81.7% at the final assessment. Therefore, 10% efinaconazole solution can be a first-line drug for longitudinal spikes, which have been regarded as refractory to oral drugs.


Assuntos
Onicomicose , Administração Tópica , Antifúngicos/uso terapêutico , Humanos , Onicomicose/tratamento farmacológico , Resultado do Tratamento , Triazóis
3.
Sci Technol Adv Mater ; 20(1): 813-825, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31489054

RESUMO

The collected end-of-life (EoL) silicon wafers from the discharged photovoltaic (PV) panels are easily contaminated by impurities such as doping elements and attached materials. In this study, the thermodynamic criteria for EoL silicon wafers refining using three most typical metallurgical refining processes: oxidation refining, evaporation refining, and solvent refining were systemically and quantitatively evaluated. A total of 42 elements (Ag, Al, Au, B, Be, Bi, C, Ca, Ce, Co, Cr, Cu, Fe, Ga, Gd, Ge, Hf, In, La, Mg, Mn, Mo, Na, Nb, Ni, Os, P, Pb, Pd, Pt, Re, Ru, Sb, Sn, Ta, Ti, U, V, W, Y, Zn, Zr) that are likely to be contained in the collected EoL silicon-based PV panels were considered. The principal findings are that the removal of aluminum, beryllium, boron, calcium, gadolinium, hafnium, uranium, yttrium, and zirconium into the slag, and removal of antimony, bismuth, carbon, lead, magnesium, phosphorus, silver, sodium, and zinc into vapor phase is possible. Further, solvent refining process using aluminum, copper, and zinc as the solvent metals, among the considered 14 potential ones, was found to be efficient for the EoL silicon wafers refining. Particularly, purification of the phosphorus doped n-type PV panels using solvent metal zinc and purification of the boron doped p-type PV panels using solvent metal aluminum are preferable. The efficiency of metallurgical processes for separating most of the impurity elements was demonstrated, and to promote the recycling efficiency, a comprehensive management and recycling system considering the metallurgical criteria of EoL silicon wafers refining is critical.

4.
J Dermatol ; 46(8): 641-651, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31206779

RESUMO

We evaluated the efficacy of efinaconazole 10% topical solution in long-term use, for up to 72 weeks, for onychomycosis, including severe cases. Among 605 participants, 219 patients diagnosed as having onychomycosis were evaluated for the efficacy of efinaconazole. The treatment success rate (<10% clinical involvement of the target toenail) at the final assessment time point was 56.6%, the complete cure rate was 31.1% and the mycological cure rate was 61.6%, all of which increased over time, demonstrating that continuous application contributed to the improvement of cure rate. Even in severe cases, reduction of the affected nail area was observed, showing the potential efficacy of the treatment. Responses to a quality of life questionnaire among patients with onychomycosis, OnyCOE-t, suggested that efinaconazole treatment improved the patients' quality of life. The incidence of adverse drug reaction in the patients eligible for the assessment was 6.3%, and this developed only in the administration site in all cases. No systemic adverse event was observed. In addition, no increase in the incidence of adverse drug reaction due to long-term use was found. Efinaconazole therapy was proved to exhibit excellent balance between efficacy and safety, and thus may serve as a useful treatment option for onychomycosis.


Assuntos
Antifúngicos/administração & dosagem , Dermatoses do Pé/tratamento farmacológico , Onicomicose/tratamento farmacológico , Triazóis/administração & dosagem , Administração Tópica , Idoso , Antifúngicos/efeitos adversos , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/etiologia , Feminino , Dermatoses do Pé/diagnóstico , Humanos , Incidência , Assistência de Longa Duração/métodos , Masculino , Pessoa de Meia-Idade , Onicomicose/diagnóstico , Qualidade de Vida , Índice de Gravidade de Doença , Fatores de Tempo , Resultado do Tratamento , Triazóis/efeitos adversos
5.
Tohoku J Exp Med ; 237(2): 133-40, 2015 10.
Artigo em Inglês | MEDLINE | ID: mdl-26447086

RESUMO

Kawasaki disease (KD) is an acute systemic vasculitis that affects both small and medium-sized vessels including the coronary arteries in infants and children. Acid sphingomyelinase (ASM) is a lysosomal glycoprotein that hydrolyzes sphingomyelin to ceramide, a lipid, that functions as a second messenger in the regulation of cell functions. ASM activation has been implicated in numerous cellular stress responses and is associated with cellular ASM secretion, either through alternative trafficking of the ASM precursor protein or by means of an unidentified mechanism. Elevation of serum ASM activity has been described in several human diseases, suggesting that patients with diseases involving vascular endothelial cells may exhibit a preferential elevation of serum ASM activity. As acute KD is characterized by systemic vasculitis that could affect vascular endothelial cells, the elevation of serum ASM activity should be considered in these patients. In the present study, serum ASM activity in the sera of 15 patients with acute KD was determined both before and after treatment with infusion of high-dose intravenous immunoglobulin (IVIG), a first-line treatment for acute KD. Serum ASM activity before IVIG was significantly elevated in KD patients when compared to the control group (3.85 ± 1.46 nmol/0.1 ml/6 h vs. 1.15 ± 0.10 nmol/0.1 ml/6 h, p < 0.001), suggesting that ASM activation may be involved in the pathophysiology of this condition. Serum ASM activity before IVIG was significantly correlated with levels of C-reactive protein (p < 0.05). These results suggest the involvement of sphingolipid metabolism in the pathophysiology of KD.


Assuntos
Síndrome de Linfonodos Mucocutâneos/sangue , Esfingomielina Fosfodiesterase/sangue , Adolescente , Adulto , Biomarcadores/sangue , Proteína C-Reativa/análise , Criança , Feminino , Humanos , Imunoglobulinas Intravenosas/administração & dosagem , Imunoglobulinas Intravenosas/uso terapêutico , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Síndrome de Linfonodos Mucocutâneos/terapia , Medição de Risco , Esfingolipídeos/metabolismo , Resultado do Tratamento , Adulto Jovem
6.
Angew Chem Int Ed Engl ; 54(29): 8480-4, 2015 Jul 13.
Artigo em Inglês | MEDLINE | ID: mdl-26068934

RESUMO

The photochemical conversion of carbon dioxide provides a straightforward and effective strategy for the highly efficient production of solar fuels with high solar-light utilization efficiency. However, the high recombination rate of photoexcited electron-hole (e-h) pairs and the poor photostability have greatly limited their practical applications. Herein, a practical strategy is proposed to facilitate the separation of e-h pairs and enhance the photostability in a semiconductor by the use of a Schottky junction in a bimetal-graphene-semiconductor stack array. Importantly, Au-Cu nanoalloys (ca. 3 nm) supported on a 3D ultrathin graphene shell encapsulating a p-type Cu2O coaxial nanowire array promotes the stable photochemical reduction of CO2 to methanol by the synergetic catalytic effect of interfacial modulation and charge-transfer channel design. This work provides a promising lead for the development of practical catalysts for sustainable fuel synthesis.

7.
Environ Sci Technol ; 47(9): 4653-60, 2013 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-23528100

RESUMO

Steel is not elemental iron but rather a group of iron-based alloys containing many elements, especially chromium, nickel, and molybdenum. Steel recycling is expected to promote efficient resource use. However, open-loop recycling of steel could result in quality loss of nickel and molybdenum and/or material loss of chromium. Knowledge about alloying element substance flow is needed to avoid such losses. Material flow analyses (MFAs) indicate the importance of steel recycling to recovery of alloying elements. Flows of nickel, chromium, and molybdenum are interconnected, but MFAs have paid little attention to the interconnected flow of materials/substances in supply chains. This study combined a waste input-output material flow model and physical unit input-output analysis to perform a simultaneous MFA for nickel, chromium, and molybdenum in the Japanese economy in 2000. Results indicated the importance of recovery of these elements in recycling policies for end-of-life (EoL) vehicles and constructions. Improvement in EoL sorting technologies and implementation of designs for recycling/disassembly at the manufacturing phase are needed. Possible solutions include development of sorting processes for steel scrap and introduction of easier methods for identifying the composition of secondary resources. Recovery of steel scrap with a high alloy content will reduce primary inputs of alloying elements and contribute to more efficient resource use.


Assuntos
Cromo/química , Molibdênio/química , Níquel/química , Aço/química
8.
Jpn J Infect Dis ; 65(4): 301-5, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22814151

RESUMO

One concern about rotavirus vaccines is its possible association with intussusception. Thus, it is necessary to determine the baseline incidence for intussusception in the first year of life in places where rotavirus vaccines are introduced. However, few safety data exist for the period at which the first dose of Rotarix and RotaTeq are allowed to administer in Japan. The first dose of Rotarix is scheduled to administer at 6-20 weeks of age and that of RotaTeq is scheduled to administer at 6-24 weeks of age; the upper limits for these vaccines is later than the upper limit recommended by the World Health Organization by 5 and 9 weeks, respectively. We performed a retrospective cross-sectional study by reviewing medical charts of all hospitals that provided pediatric beds in Akita Prefecture, Japan, and identifying the cases of intussusception that met the Brighton criteria level 1 in these hospitals between January 2001 and December 2010. During this 10-year period, 122 children younger than 1 year of age were diagnosed with intussusception. The incidence of intussusception was estimated at 158 per 100,000 person-years among children younger than 1 year (95% confidence interval, 131-188), 10 per 100,000 person-years for children aged 0-2 months, 165 for children aged 3-5 months, and 300 for children aged 6-8 months. This rapid and substantial increase in the incidence of intussusception during the first year of life should be considered when formulating the immunization schedule for administering rotavirus vaccines in Japan.


Assuntos
Intussuscepção/epidemiologia , Estudos Transversais , Humanos , Incidência , Lactente , Recém-Nascido , Intussuscepção/etiologia , Japão/epidemiologia , Estudos Retrospectivos , Vacinas contra Rotavirus/efeitos adversos
9.
Environ Sci Technol ; 45(11): 4929-36, 2011 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-21561121

RESUMO

This study presents the results of chemical thermodynamic analysis on the distribution of elements in the smelting process of metallic materials to examine the controllability of impurities in the pyrometallurgical technique. The results of the present work can give an answer against the frequently given question; "Which impurity element can be removable in metallurgical process?" or "How far can the impurity level be controlled?". The proposed method was applied to estimate the distribution of 29 elements for a copper converter and 26 elements for a steel-making process and shows the distribution tendency of elements among the gas, slag, and metal phases as well as clarifying which metals can be recovered or removed from secondary resources in metallurgical processes. The effects of temperature, oxygen partial pressure, and slag composition on the distribution ratio of elements were also evaluated, and the removal limit or controllability of impurity in these two processes was presented. This study results in thermodynamic features of various elements in the pyrometallurgical process and also shows, even by varying process parameters such as temperature and oxygen partial pressure, no drastic improvement of removal efficiency should be expected, except for lead and tin in copper.


Assuntos
Metalurgia/normas , Metais/química , Reciclagem/métodos , Cobre/análise , Elementos Químicos , Oxigênio , Aço/análise , Temperatura
10.
Sci Technol Adv Mater ; 12(3): 035003, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27877407

RESUMO

In this paper, the possibility of removing impurities during magnesium recycling with pyrometallurgical techniques has been evaluated by using a thermodynamic analysis. For 25 different elements that are likely to be contained in industrial magnesium alloys, the equilibrium distribution ratios between the metal, slag and gas phases in the magnesium remelting process were calculated assuming binary systems of magnesium and an impurity element. It was found that calcium, gadolinium, lithium, ytterbium and yttrium can be removed from the remelted end-of-life (EoL) magnesium products by oxidization. Calcium, cerium, gadolinium, lanthanum, lithium, plutonium, sodium, strontium and yttrium can be removed by chlorination with a salt flux. However, the other elements contained in magnesium alloy scrap are scarcely removed and this may contribute toward future contamination problems. The third technological option for the recycling of EoL magnesium products is magnesium recovery by a distillation process. Based on thermodynamic considerations, it is predicted that high-purity magnesium can be recovered through distillation because of its high vapor pressure, yet there is a limit on recoverability that depends on the equilibrium vapor pressure of the alloying elements and the large energy consumption. Therefore, the sustainable recycling of EoL magnesium products should be an important consideration in the design of advanced magnesium alloys or the development of new refining processes.

11.
Environ Sci Technol ; 44(14): 5594-600, 2010 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-20536230

RESUMO

In previous studies on the physical chemistry of pyrometallurgical processing of aluminum scrap, only a limited number of thermodynamic parameters, such as the Gibbs free energy change of impurity reactions and the variation of activity of an impurity in molten aluminum, were taken into account. In contrast, in this study we thermodynamically evaluated the quantitative removal limit of impurities during the remelting of aluminum scrap; all relevant parameters, such as the total pressure, the activity coefficient of the target impurity, the temperature, the oxygen partial pressure, and the activity coefficient of oxidation product, were considered. For 45 elements that usually occur in aluminum products, the distribution ratios among the metal, slag, and gas phases in the aluminum remelting process were obtained. Our results show that, except for elements such as Mg and Zn, most of the impurities occurred as troublesome tramp elements that are difficult to remove, and our results also indicate that the extent to which the process parameters such as oxygen partial pressure, temperature, and flux composition can be changed in aluminum production is quite limited compared to that for iron and copper production, owing to aluminum's relatively low melting point and strong affinity for oxygen. Therefore, the control of impurities in the disassembly process and the quality of scrap play important roles in suppressing contamination in aluminum recycling.


Assuntos
Ligas , Alumínio , Conservação dos Recursos Naturais , Termodinâmica
12.
Mol Cell Probes ; 22(5-6): 333-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18761082

RESUMO

A simple and non-expensive platform is critical to realize on-site SNP typing. In this study we typed an SNP existing at the 487th residue of human aldehyde dehydrogenase2 [wild: Glu (GAA); mutant: Lys (AAA)] using our unique isothermal DNA amplification method, ICAN and cycling probes. Both genotypes were identified by the naked eye using a non-expensive UV transilluminator as well as with real-time PCR apparatus or a fluorescence detector. Since ICAN does not need thermal cycling, a cost- and space-limiting factor when fabricating apparatus, the combination of ICAN and cycling probes will be able to realize affordable on-site SNP typing in the near future.


Assuntos
Aldeído Desidrogenase/genética , Técnicas de Amplificação de Ácido Nucleico , Polimorfismo de Nucleotídeo Único , Análise de Sequência de DNA , Adulto , Aldeído-Desidrogenase Mitocondrial , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Técnicas de Amplificação de Ácido Nucleico/instrumentação , Técnicas de Amplificação de Ácido Nucleico/métodos , Análise de Sequência de DNA/instrumentação , Análise de Sequência de DNA/métodos
13.
Oncol Rep ; 19(1): 99-104, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-18097581

RESUMO

Squamous cell carcinoma antigen (SCCA) has been used for the management of squamous cell carcinoma, especially in order to evaluate therapeutic effects and monitor recurrence. Recent studies have shown that SCCA performs several biological functions and can influence the behavior of cancer cells. It is well known that altered expression of E-cadherin is involved in the process of cancer invasion and metastasis. The present study was therefore undertaken to investigate the relationship between the expression of SCCA, E-cadherin and lymph node metastasis in advanced cervical squamous cell carcinoma patients. We studied 70 patients who had undergone radical hysterectomy and pelvic lymphadenectomy for stage IB, IIA and IIB of the disease, without pretreatments. Immunohistochemistry, using monoclonal antibodies against SCCA2 and E-cadherin, was performed to examine the relationship between SCCA2 and E-cadherin expression patterns in primary cancer lesions and lymph node metastasis. There was a significant positive relationship between the two expression patterns in primary cancer lesions (p<0.01). Both exhibited a heterogeneous expression pattern in the primary tumor which indicated a significant relationship with lymph node metastasis (p<0.01). Our data clearly show that SCCA2 expression is significantly related to E-cadherin expression and that the heterogeneous pattern of SCCA and E-cadherin in primary lesions is strongly associated with the high incidence of lymph node metastasis in cervical squamous cell carcinoma. These findings suggest that SCCA2 may be involved in cancer behavior such as metastasis, and as such can be a useful marker in predicting lymph node metastasis.


Assuntos
Antígenos de Neoplasias/biossíntese , Biomarcadores Tumorais/análise , Caderinas/biossíntese , Carcinoma de Células Escamosas/patologia , Metástase Linfática/patologia , Serpinas/biossíntese , Neoplasias do Colo do Útero/patologia , Carcinoma de Células Escamosas/metabolismo , Feminino , Expressão Gênica , Humanos , Imuno-Histoquímica , Invasividade Neoplásica/fisiopatologia , Estadiamento de Neoplasias , Neoplasias do Colo do Útero/metabolismo
14.
Biol Pharm Bull ; 30(9): 1663-7, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17827717

RESUMO

Phenyl-substituted dihydropyrazines (Ph-DHPs) are derivatives of 2,3-dihydro-5,6-dimethylpyrazine (Me-DHP). Upon the addition of Cu(2+), Me-DHP inhibits the growth of Escherichia coli by generating hydroxyl and carbon-centered radicals that cause DNA strand breakage. Here, we investigated the toxic effect of Ph-DHPs in several DNA repair-deficient or detoxifying enzyme-deficient mutant strains. Ph-DHPs caused cytotoxic and genotoxic damage, but, in a sodA sodB strain, the effects in the presence or absence of Cu(2+) were different than those of Me-DHP. Our results suggest that the action of the generated superoxide anion in the interior side of the cell is remarkable.


Assuntos
Escherichia coli K12/metabolismo , Pirazinas/farmacologia , Ácido Aminolevulínico/metabolismo , Cobre/farmacologia , DNA/efeitos dos fármacos , DNA/genética , Reparo do DNA/efeitos dos fármacos , Espectroscopia de Ressonância de Spin Eletrônica , Escherichia coli K12/efeitos dos fármacos , Escherichia coli K12/genética , Neoplasias Hepáticas/induzido quimicamente , Neoplasias Hepáticas/patologia , Mutação , Éteres Fenílicos/química , Éteres Fenílicos/metabolismo , Pirazinas/química , Sais de Tetrazólio/metabolismo
15.
J Biochem ; 142(2): 283-92, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17720719

RESUMO

Isothermal and Chimeric primer-initiated Amplification of Nucleic acids (ICAN) allows the amplification of target DNA under isothermal conditions at around 55 degrees C using only a pair of 5'-DNA-RNA-3' chimeric primers, thermostable RNaseH and a DNA polymerase with strand-displacing activity (H. Mukai et al. J. Biochemistry, in the preceding paper in this issue). Here we elucidated the mechanism of ICAN by analysing the nicking site of RNaseH, behaviour of chimeric primers and extension products. We found that the ICAN reaction was composed of two unique mechanisms, multi-priming and template-switching, that were responsible for the highly efficient amplifying capability of ICAN. The simultaneous occurrence of two types of reactions, one based on multi-priming and the other based on template-switching, is likely to drive the DNA amplification in ICAN.


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , Quebras de DNA de Cadeia Simples , Primers do DNA/química , Modelos Biológicos , Ribonuclease H/metabolismo
16.
J Biochem ; 142(2): 273-81, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17720718

RESUMO

We developed an efficient method of isothermally amplifying DNA termed ICAN, Isothermal and Chimeric primer-initiated Amplification of Nucleic acids. This method allows the amplification of target DNA under isothermal conditions at around 55 degrees C using only a pair of 5'-DNA-RNA-3' chimeric primers, a thermostable RNaseH and a DNA polymerase with strong strand-displacing activity. ICAN is capable of amplifying DNA at least several times greater than the amount produced with PCR by increasing primer concentration. This method would be applicable for on-site DNA detection including gene diagnosis, and would also be suitable for 'real time' detection when combined with a cycling probe.


Assuntos
Primers do DNA/química , DNA Polimerase Dirigida por DNA/metabolismo , DNA/metabolismo , Técnicas de Amplificação de Ácido Nucleico/métodos , RNA/química , Ribonuclease H/metabolismo , Temperatura , Ribonuclease H/química
17.
Oncol Rep ; 18(1): 175-9, 2007 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-17549365

RESUMO

Squamous cell carcinoma antigen (SCCA) has been used for the management of squamous cell carcinoma, especially for evaluating therapeutic effects and monitoring recurrence. It has been reported that SCCA has several biological activities and influences behavior of cancer cells. E-cadherin is a cell adhesion molecule and plays important roles in the process of cancer invasion and metastasis. Our previous studies have shown that blockage of E-cadherin action by anti-E-cadherin antibody treatment suppresses SCCA production in squamous cell carcinoma cells. This finding strongly suggests that E-cadherin regulates SCCA expression. The present study was, therefore, undertaken to investigate the correlation between E-cadherin and SCCA2. For this purpose, E-cadherin cDNA was transfected into squamous cell carcinoma cell lines, SiHa and SKG IIIa. Overexpression of E-cadherin increased SCCA2 expression together with cell aggregation. We also examined the involvement of phosphatidylinositol 3-kinase (PI3K)-Akt pathway, which is one of major signaling pathways from E-cadherin. E-cadherin transfection increased phosphorylated Akt expression concomitantly with the increase in SCCA2 expression, and the increased SCCA2 expression was inhibited by a PI3K inhibitor. In conclusion, SCCA2 is up-regulated by E-cadherin through PI3K-Akt pathway, suggesting that SCCA2, as well as E-cadherin, may be involved in the regulation of cancer behavior.


Assuntos
Antígenos de Neoplasias/metabolismo , Caderinas/fisiologia , Carcinoma de Células Escamosas/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Serpinas/metabolismo , Neoplasias do Colo do Útero/metabolismo , Western Blotting , Carcinoma de Células Escamosas/patologia , Feminino , Humanos , Invasividade Neoplásica/patologia , Fosforilação , Transdução de Sinais , Transfecção , Células Tumorais Cultivadas , Neoplasias do Colo do Útero/patologia
18.
Int J Oncol ; 29(5): 1231-5, 2006 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17016656

RESUMO

Squamous cell carcinoma antigen (SCCA) is a useful tumor marker for diagnosis and management of squamous cell carcinoma. Recent studies have shown that SCCA can influence the behavior of cancer cells. It is well known that cell-cell adhesion is an important factor for the progression of cancer. The present study, therefore, was undertaken to investigate the effect of SCCA2 on the cell adhesion related molecule, E-cadherin, and cancer cell behavior. For this purpose, antisense SCCA2 cDNA was transfected into human uterine cancer cell lines, SKG IIIa and SiHa, which express SCCA2. Suppression of SCCA2 expression by antisense SCCA2 cDNA transfection decreased E-cadherin expression and promoted cell migration and invasion as well as the blockage of E-cadherin function by anti-E-cadherin antibody administration. In conclusion, SCCA2 regulates cell migration and invasion via E-cadherin expression, suggesting that SCCA2 may be involved in cancer behavior such as invasion or metastasis.


Assuntos
Antígenos de Neoplasias/fisiologia , Caderinas/antagonistas & inibidores , Adesão Celular , Movimento Celular , Invasividade Neoplásica/genética , Serpinas/fisiologia , Antígenos de Neoplasias/genética , Adesão Celular/efeitos dos fármacos , Adesão Celular/genética , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Movimento Celular/genética , DNA Antissenso/farmacologia , Humanos , Serpinas/genética
19.
Oncol Rep ; 16(2): 399-404, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16820922

RESUMO

Squamous cell carcinoma antigen (SCCA), a 45-kDa tumor-associated serpin, mainly consists of two highly homologous molecules, SCCA1 and SCCA2, which possess unique proteinase inhibitory properties. Importantly, our previous study demonstrated that an intact structure of SCCAs, and not a cleaved form yielded by interacting with target proteinase, is essential for their function as a serpin. The aim of this study is therefore, to develop a simple method of analyzing expression patterns of intact forms of SCCAs (functional SCCAs) in cervical squamous epithelial tissues and to investigate whether there are any differences in the expression of intact forms of SCCAs between normal and malignant cervical squamous epithelial tissues. We used nondenaturing polyacrylamide gel electrophoresis (PAGE) with immunoblotting. The newly generated antibody, Pab Y2, recognizes only intact form of SCCAs, while the conventional antibody, Mab 27, reacts with the cleaved form of SCCA1 as well as intact forms of SCCAs. Nondenaturing PAGE using Pab Y2 showed that an intact form of SCCAs in the heat-treated tissue extract at 60 degrees C for 2 h was separated into at least five bands, termed as bands A-E from cathode to anode. By comparison with two-dimensional electrophoresis patterns of SCCAs, it was found that the first three bands, i.e. bands A-C, are derived from the intact form of SCCA1, while the other two bands, i.e. band D and E are from the intact form of SCCA2. Specifically, band E, but not band D, of SCCA2 is apparently increased in squamous cell carcinomas compared with normal squamous epithelium. In conclusion, this novel analytical approach will be useful for investigating the different expression patterns of functional SCCAs between normal and malignant cervical squamous epithelial tissues.


Assuntos
Antígenos de Neoplasias/análise , Eletroforese em Gel de Poliacrilamida/métodos , Neoplasias de Células Escamosas/química , Serpinas/análise , Neoplasias do Colo do Útero/química , Colo do Útero/química , Feminino , Humanos , Desnaturação Proteica
20.
Int J Oncol ; 27(5): 1345-53, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16211231

RESUMO

Squamous cell carcinoma antigen (SCCA) is clinically used as a tumor marker for patients with squamous cell carcinoma of various organs. SCCA1 and its highly homologous molecule, SCCA2, belong to the serine proteinase inhibitors (serpins) family, suggesting that these proteins may be involved in the malignant behavior of squamous cell carcinoma cells. The aim of this study is to functionally characterize these tumor-associated serpins regarding the potential to influence the production of matrix metalloproteinases (MMPs), which play a key role in tumor cell invasion and metastasis. Cervical squamous cell carcinoma cell lines, CaSki cells and SKG-IIIa cells were incubated with SCCA1 or SCCA2 and MMP production was analyzed by gelatin zymography. Both SCCA1 and SCCA2 significantly increased production of proMMP-9, but not proMMP-2. These stimulatory effects were still observed when cells were treated with SCCA mutants lacking the proteinase inhibitory activity of serpins. Furthermore, treatments with various forms of SCCAs, which are generated by interacting with their target proteinases, diminished the stimulatory effect of SCCAs, implying the importance of the conformational structure of SCCAs in the stimulatory effects of SCCAs on proMMP-9 production. In addition, in vitro invasion assay showed that SCCA1 and SCCA2 significantly promoted the activity of cell invasion. It is concluded that SCCAs can alter the invasive phenotype of cervical squamous cell carcinoma cells, probably by stimulating proMMP-9 production, and that intact conformational structure of SCCAs, but not proteinase inhibitory activity of serpins, is required for its stimulatory activity on proMMP-9 production.


Assuntos
Antígenos de Neoplasias/fisiologia , Carcinoma de Células Escamosas/genética , Metaloproteinases da Matriz/biossíntese , Serpinas/fisiologia , Neoplasias do Colo do Útero/genética , Antígenos de Neoplasias/biossíntese , Antígenos de Neoplasias/genética , Feminino , Humanos , Invasividade Neoplásica , Fenótipo , Conformação Proteica , Serpinas/biossíntese , Serpinas/genética , Células Tumorais Cultivadas
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