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2.
Biochim Biophys Acta Mol Cell Res ; 1866(9): 1475-1486, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31220477

RESUMO

Sphingosine kinase 1 (SK1) converts sphingosine to the bioactive lipid sphingosine 1-phosphate (S1P). S1P binds to G-protein-coupled receptors (S1PR1-5) to regulate cellular events, including Ca2+ signaling. The SK1/S1P axis and Ca2+ signaling both play important roles in health and disease. In this respect, Ca2+ microdomains at the mitochondria-associated endoplasmic reticulum (ER) membranes (MAMs) are of importance in oncogenesis. Mitofusin 2 (MFN2) modulates ER-mitochondria contacts, and dysregulation of MFN2 is associated with malignancies. We show that overexpression of SK1 augments agonist-induced Ca2+ release from the ER resulting in increased mitochondrial matrix Ca2+. Also, overexpression of SK1 induces MFN2 fragmentation, likely through increased calpain activity. Further, expressing putative calpain-cleaved MFN2 N- and C-terminal fragments increases mitochondrial matrix Ca2+ during agonist stimulation, mimicking the SK1 overexpression in cells. Moreover, SK1 overexpression enhances cellular respiration and cell migration. Thus, SK1 regulates MFN2 fragmentation resulting in increased mitochondrial Ca2+ and downstream cellular effects.


Assuntos
GTP Fosfo-Hidrolases/metabolismo , Mitocôndrias/metabolismo , Proteínas Mitocondriais/metabolismo , Fosfotransferases (Aceptor do Grupo Álcool)/metabolismo , Cálcio/metabolismo , Movimento Celular , Proliferação de Células , Retículo Endoplasmático/metabolismo , Células HeLa , Humanos , Lisofosfolipídeos , Mitocôndrias/patologia , Transdução de Sinais , Esfingosina/análogos & derivados , Receptores de Esfingosina-1-Fosfato
4.
Zhonghua Yi Xue Za Zhi ; 97(2): 99-103, 2017 Jan 10.
Artigo em Chinês | MEDLINE | ID: mdl-28088952

RESUMO

Objective: To compare the safety and effectiveness between antithymocyte globulin (ATG) and basiliximab in deceased donor renal transplantation within matched groups where paired recipients received graft donations from same donors. Methods: A total of 124 cases of deceased donor kidney transplantation performed at Wuhan Tongji Hospital from January 2013 to November 2015 were retrospectively analyzed. Based upon their induction therapies, the recipients receiving graft donations from same donors were divided into two groups, namely ATG group (n=62) and basiliximab group (n=62). Clinical data were gathered and comparisons were made between the two groups. Results: Delayed graft function (DGF) implicated less patients in the ATG group (11, 17.7%) compared with basiliximab group (21, 33.9%) (P=0.040). Duration of DGF was also significantly shorter in the ATG group than in the basiliximab group[(14.92±6.23) vs(20.26±7.89)days, P=0.048]. The rates of DGF were 5/18 in the ATG group and 10/15 in the basiliximab group (P=0.025), when subgrouping the patients with elevated risk factors (donor age >50 or a history of hypertension or graft cold ischemia time >24 h) for DGF. The acute rejection rates did not differ between the two groups significantly; comparable one-year graft and patient survival were observed between the ATG and basiliximab groups(all P>0.05). Conclusions: The duration of DGF and DGF rate after deceased donor renal transplantation is reduced by ATG, when compared with basiliximab. Moreover, in recipients with elevated risk factors for DGF, ATG diminishes DGF incidence significantly.


Assuntos
Transplante de Rim , Anticorpos Monoclonais , Soro Antilinfocitário , Basiliximab , Função Retardada do Enxerto , Rejeição de Enxerto , Sobrevivência de Enxerto , Humanos , Imunossupressores , Incidência , Proteínas Recombinantes de Fusão , Estudos Retrospectivos , Fatores de Risco , Doadores de Tecidos
5.
Lupus ; 22(14): 1484-8, 2013 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24142583

RESUMO

Neonatal lupus is a rare and acquired autoimmune disease. Central nervous system abnormalities are potential manifestations in neonatal lupus. Through a systematic literature review, we analyzed the clinical features of previously reported neonatal lupus cases where central nervous system abnormalities had been identified. Most reported neonatal lupus patients with central nervous system involvement were neuroimaging-determined and asymptomatic. Only seven neonatal lupus cases were identified as having a symptomatic central nervous system abnormality which caused physical disability or required neurosurgery. A high percentage of these neurosymptomatic neonatal lupus patients had experienced a transient cutaneous skin rash and had no maternal history of autoimmune disease before pregnancy.


Assuntos
Lúpus Eritematoso Sistêmico/congênito , Vasculite Associada ao Lúpus do Sistema Nervoso Central/fisiopatologia , Feminino , Humanos , Recém-Nascido , Lúpus Eritematoso Sistêmico/fisiopatologia , Vasculite Associada ao Lúpus do Sistema Nervoso Central/congênito , Vasculite Associada ao Lúpus do Sistema Nervoso Central/cirurgia , Procedimentos Neurocirúrgicos/métodos , Gravidez
6.
Hum Exp Toxicol ; 32(4): 344-53, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23613483

RESUMO

The effect of the natural product diindolylmethane (DIM) on cytosolic Ca(2+) concentrations ([Ca(2+)]i) and viability in MDCK renal tubular cells was explored. The Ca(2+)-sensitive fluorescent dye fura-2 was applied to measure [Ca(2+)]i. DIM at concentrations 1-50 µM induced a [Ca(2+)]i rise in a concentration-dependent manner. The response was reduced partly by removing Ca(2+). DIM induced Mn(2+) influx leading to quenching of fura-2 fluorescence. DIM-evoked Ca(2+) entry was suppressed by nifedipine, econazole, SK&F96365 and protein kinase C modulators. In the absence of extracellular Ca(2+), incubation with the endoplasmic reticulum Ca(2+) pump inhibitor thapsigargin (TG) or 2,5-di-tert-butylhydroquinone (BHQ) greatly inhibited DIM-induced [Ca(2+)]i rise. Incubation with DIM abolished TG or BHQ-induced [Ca(2+)]i rise. Inhibition of phospholipase C with U73122 reduced DIM-induced [Ca(2+)]i rise by 50%. At 1, 10, 40 and 50 µM, DIM slightly enhanced cell proliferation. The effect of 50 µM DIM was reversed by chelating cytosolic Ca(2+) with 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid. In sum, in MDCK cells, DIM induced a [Ca(2+)]i rise by evoking phospholipase C-dependent Ca(2+) release from the endoplasmic reticulum and Ca(2+) entry via protein kinase C-sensitive store-operated Ca(2+) channels. DIM did not induce cell death.


Assuntos
Produtos Biológicos/farmacologia , Cálcio/metabolismo , Indóis/farmacologia , Animais , Sobrevivência Celular/efeitos dos fármacos , Cães , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/metabolismo , Homeostase/efeitos dos fármacos , Túbulos Renais/citologia , Células Madin Darby de Rim Canino , Fosfolipases Tipo C/metabolismo
7.
Br J Cancer ; 108(1): 72-81, 2013 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-23257894

RESUMO

BACKGROUND: Sorafenib is the only drug approved for the treatment of hepatocellular carcinoma (HCC). The bioenergetic propensity of cancer cells has been correlated to anticancer drug resistance, but such correlation is unclear in sorafenib resistance of HCC. METHODS: Six sorafenib-naive HCC cell lines and one sorafenib-resistant HCC cell line (Huh-7R; derived from sorafenib-sensitive Huh-7) were used. The bioenergetic propensity was calculated by measurement of lactate in the presence or absence of oligomycin. Dichloroacetate (DCA), a pyruvate dehydrogenase kinase (PDK) inhibitor, and siRNA of hexokinase 2 (HK2) were used to target relevant pathways of cancer metabolism. Cell viability, mitochondrial membrane potential, and sub-G1 fraction were measured for in vitro efficacy. Reactive oxygen species (ROS), adenosine triphosphate (ATP) and glucose uptake were also measured. A subcutaneous xenograft mouse model was used for in vivo efficacy. RESULTS: The bioenergetic propensity for using glycolysis correlated with decreased sorafenib sensitivity (R(2)=0.9067, among sorafenib-naive cell lines; P=0.003, compared between Huh-7 and Huh-7 R). DCA reduced lactate production and increased ROS and ATP, indicating activation of oxidative phosphorylation (OXPHOS). DCA markedly sensitised sorafenib-resistant HCC cells to sorafenib-induced apoptosis (sub-G1 (combination vs sorafenib): Hep3B, 65.4±8.4% vs 13±2.9%; Huh-7 R, 25.3± 5.7% vs 4.3±1.5%; each P<0.0001), whereas siRNA of HK2 did not. Sorafenib (10 mg kg(-1) per day) plus DCA (100 mg kg(-1) per day) also resulted in superior tumour regression than sorafenib alone in mice (tumour size: -87% vs -36%, P<0.001). CONCLUSION: The bioenergetic propensity is a potentially useful predictive biomarker of sorafenib sensitivity, and activation of OXPHOS by PDK inhibitors may overcome sorafenib resistance of HCC.


Assuntos
Carcinoma Hepatocelular/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Neoplasias Hepáticas/tratamento farmacológico , Fosforilação Oxidativa , Animais , Apoptose , Carcinoma Hepatocelular/metabolismo , Linhagem Celular Tumoral , Glicólise , Humanos , Neoplasias Hepáticas/metabolismo , Camundongos , Niacinamida/análogos & derivados , Compostos de Fenilureia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piruvato Desidrogenase Quinase de Transferência de Acetil , Sorafenibe , Ensaios Antitumorais Modelo de Xenoenxerto
8.
Lupus ; 21(14): 1582-5, 2012 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-23161579

RESUMO

Neonatal lupus is a passively acquired autoimmune syndrome resulting from the transplacental passage of maternal anti-Ro/SSA and/or anti-La/SSB antibodies to the fetus. Few past studies have reported central nervous system involvement in neonatal lupus, and most cases had a good neurological outcome. We report here a preterm case of neonatal lupus with thrombocytopenia and comorbid hemorrhagic stroke. In the follow-up, the infant developed spastic quadriplegia and showed delayed milestones. We believe that this is the first reported case of neonatal lupus accompanied by perinatal hemorrhagic stroke. We present this case to remind clinicians to conduct regular central nervous system surveys in cases of neonatal lupus.


Assuntos
Hemorragia Cerebral/etiologia , Lúpus Eritematoso Sistêmico/congênito , Acidente Vascular Cerebral/etiologia , Trombocitopenia/etiologia , Hemorragia Cerebral/patologia , Humanos , Recém-Nascido , Lúpus Eritematoso Sistêmico/complicações , Masculino , Nascimento Prematuro , Quadriplegia/etiologia , Acidente Vascular Cerebral/patologia
9.
Ultrasound Obstet Gynecol ; 39(4): 452-7, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21656867

RESUMO

OBJECTIVE: To compare the anatomical difference using three-dimensional (3D) ultrasound between the urethra at rest and during straining, in women who have undergone a tension-free vaginal tape (TVT) or TVT-obturator tape (TVT-O) procedure for stress urinary incontinence (SUI). METHODS: We reviewed retrospectively 48 women with SUI who had undergone either a TVT (n = 24) or a TVT-O (n = 24) procedure. All women underwent urinalysis, pelvic examination, pad test, 3D perineal ultrasonography and personal interview about urinary symptoms within 1 year after surgery. RESULTS: After both TVT and TVT-O procedures, the area and longest and shortest diameters of the hypoechoic core of the mid-urethra were significantly smaller during straining than during resting (P < 0.01). The distance between tape and urethra was similarly smaller during straining in both groups. Analysis of ultrasound measurements in women reporting success (n = 40) and those reporting failure (n = 8) of the procedure showed the area and longest and shortest diameters of the hypoechoic core of the mid-urethra to be significantly smaller during straining than during resting in both groups (P < 0.01). However, the shortest diameter of the proximal and distal urethra during straining were significantly smaller only in the successful group (P < 0.01). CONCLUSION: There are differences in urethral morphology during straining compared with during resting in women with TVT and those with TVT-O, regardless of tape procedure. A urethral compression effect of slings may have an important role in the continence mechanism.


Assuntos
Slings Suburetrais , Uretra/diagnóstico por imagem , Incontinência Urinária por Estresse/diagnóstico por imagem , Feminino , Humanos , Pessoa de Meia-Idade , Estudos Retrospectivos , Resultado do Tratamento , Ultrassonografia , Uretra/fisiopatologia , Incontinência Urinária por Estresse/fisiopatologia , Incontinência Urinária por Estresse/cirurgia , Urodinâmica
11.
Eur J Neurol ; 18(2): 252-259, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20561038

RESUMO

BACKGROUND: Patients with acute disseminated encephalomyelitis (ADEM) may relapse and some may ultimately convert to multiple sclerosis (MS); however, no criteria that can predict MS conversion are available to date. Our aim was to describe the clinical and magnetic resonance imaging (MRI) features of patients with an initial ADEM attack and evaluate which MRI criteria can predict conversion to MS. METHODS: We retrospectively reviewed the records of 36 patients diagnosed with ADEM. We determined clinical signs/symptoms, examined the cerebrospinal fluid (CSF), and performed brain MRI scans and compared the findings between patients who did and did not convert to MS. RESULTS: Clinical signs/symptoms, and CSF analysis show no significant difference between the two groups. The rate of conversion to MS from ADEM in Taiwanese patients is low (11%) after a mean follow-up period of 28.36 months. Modified McDonald criteria were fulfilled in 19/36 patients: 21% (4/19) of those patients developed MS according to Poser criteria subsequently. Of the other patients (17/36) who did not fulfill these criteria, none converted to MS. (log rank test; P=0.027). CONCLUSIONS: It is difficult to predict from initial clinical presentations to address which patients with ADEM will convert to MS. Patients with ADEM whose brain MRI findings met the modified McDonald criteria may have clinically isolated syndrome because they have a significantly higher probability of conversion to MS. In contrast, patients whose brain MRI findings did not meeting these criteria may be considered as having classic ADEM because they have a lower probability of conversion to MS.


Assuntos
Encefalomielite Aguda Disseminada/complicações , Encefalomielite Aguda Disseminada/patologia , Esclerose Múltipla/etiologia , Esclerose Múltipla/patologia , Adulto , Pré-Escolar , Progressão da Doença , Feminino , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taiwan
12.
Cell Biochem Funct ; 28(8): 695-705, 2010 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-21104938

RESUMO

Furano-1,2-naphthoquinone (FNQ), prepared from 2-hydroxy-1,4-naphthoquinone and chloroacetaldehyde in an efficient one-pot reaction, exhibits an anti-carcinogenic effect. FNQ exerted anti-proliferative activity with the G(2)/M cell cycle arrest and apoptosis in A549 cells. FNQ-induced G(2)/M arrest was correlated with a marked decrease in the expression levels of cyclin A and cyclin B, and their activating partner cyclin-dependent kinases (Cdk) 1 and 2 with concomitant induction of p53, p21, and p27. FNQ-induced apoptosis was accompanied with Bax up-regulation and the down-regulation of Bcl-2, X-linked inhibitor of apoptosis (XIAP), and survivin, resulting in cytochrome c release and sequential activation of caspase-9 and caspase-3. Western blot analysis revealed that FNQ suppressed EGFR phosphorylation and JAK2, STAT3, and STAT5 activation, but increased in activation of p38 MAPK and c-Jun NH2-terminal kinase (JNK) stress signal. The combined treatment of FNQ with AG1478 (a specific EGFR inhibitor) significantly enhanced the G(2)/M arrest and apoptosis, and also led to up-regulation in Bax, p53, p21, p27, release of mitochondrial cytochrome c, and down-regulation of Bcl-2, XIAP, survivin, cyclin A, cyclin B, Cdk1, and Cdk2 in A549 cells. These findings suggest that FNQ-mediated cytotoxicity of A549 cell related with the G(2)/M cell cycle arrest and apoptosis via inactivation of EGFR-mediated signaling pathway.


Assuntos
Apoptose/efeitos dos fármacos , Divisão Celular/efeitos dos fármacos , Receptores ErbB/fisiologia , Furanos/farmacologia , Fase G2/efeitos dos fármacos , Naftoquinonas/farmacologia , Proliferação de Células , Ativação Enzimática/efeitos dos fármacos , Furanos/antagonistas & inibidores , Humanos , Proteínas Inibidoras de Apoptose/biossíntese , Janus Quinase 2/metabolismo , Neoplasias Pulmonares , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/fisiologia , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Naftoquinonas/antagonistas & inibidores , Fosforilação , Proteínas Proto-Oncogênicas c-bcl-2/biossíntese , Fator de Transcrição STAT3/metabolismo , Fator de Transcrição STAT5/metabolismo , Transdução de Sinais/efeitos dos fármacos , Células Tumorais Cultivadas
13.
J R Soc Interface ; 7(48): 1025-31, 2010 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-20031984

RESUMO

Boron plays important roles in many life processes including embryogenesis, bone growth and maintenance, immune function and psychomotor skills. Thus, the delivery of boron by the degradation of borate glass is of special interest in biomedical applications. However, the cytotoxicity of borate glass which arises with the rapid release of boron has to be carefully considered. In this study, it was found that the incorporation of strontium into borate glass can not only moderate the rapid release of boron, but also induce the adhesion of osteoblast-like cells, SaOS-2, thus significantly increasing the cyto-compatibility of borate glass. The formation of multilayers of apatite with porous structure indicates that complete degradation is optimistic, and the spread of SaOS-2 covered by apatite to form a sandwich structure may induce bone-like tissue formation at earlier stages. Therefore, such novel strontium-incorporated borosilicate may act as a new generation of biomaterial for bone regeneration, which not only renders boron as a nutritious element for bone health, but also delivers strontium to stimulate formation of new bones.


Assuntos
Vidro/química , Apatitas , Materiais Biocompatíveis/química , Regeneração Óssea , Osso e Ossos , Boratos , Boro , Humanos , Osteoblastos , Osteogênese , Porosidade , Estrôncio
14.
Opt Express ; 17(15): 12910-21, 2009 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-19654696

RESUMO

This work investigates a novel color cone lasing emission (CCLE) based on a one-dimensional photonic crystal-like dye-doped cholesteric liquid crystal (DDCLC) film with a single pitch. The lasing wavelength in the CCLE is distributed continuously at 676.7-595.6 nm, as measured at a continuously increasing oblique angle relative to the helical axis of 0-50 degrees . This work demonstrates that lasing wavelength coincides exactly with the wavelength at the long wavelength edge of the CLC reflection band at oblique angles of 0-50 degrees . Simulation results of dispersion relations at different oblique angles using Berreman's 4X4 matrix method agrees closely with experimental results. Some unique and important features of the CCLE are identified and discussed.


Assuntos
Colesterol/química , Cristais Líquidos/química , Óptica e Fotônica , Simulação por Computador , Desenho de Equipamento , Vidro , Lasers , Álcool de Polivinil/química , Refratometria
15.
Hum Exp Toxicol ; 28(5): 301-8, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19661262

RESUMO

The effect of thimerosal on cytosolic free Ca(2+) concentrations ([Ca(2+)](i) ) in human oral cancer cells (OC2) is unclear. This study explored whether thimerosal changed basal [Ca(2+)](i) levels in suspended OC2 cells using fura-2. Thimerosal at concentrations between 1and 50 microM increased [Ca(2+)](i) in a concentration-dependent manner. The Ca(2+) signal was reduced partly by removing extracellular Ca( 2+). Thimerosal-induced Ca(2+) influx was not blocked by L-type Ca(2+) entry inhibitors and protein kinase C modulators (phorbol 12-myristate 13-acetate [PMA] and GF109203X). In Ca(2+)-free medium, 50 microM thimerosal failed to induce a [Ca(2+)](i) rise after pretreatment with thapsigargin (an endoplasmic reticulum Ca(2+) pump inhibitor). Inhibition of phospholipase C with U73122 did not change thimerosal-induced [Ca(2+)](i) rises. At concentrations between 5 and 10 microM, thimerosal killed cells in a concentration-dependent manner. The cytotoxic effect of 8 muM thimerosal was potentiated by prechelating cytosolic Ca(2+) with the Ca(2+) chelator 1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetate/acetomethyl (BAPTA/ AM). Flow cytometry data suggested that 1-7 microM thimerosal-induced apoptosis in a concentration-dependent manner. Collectively, in OC2 cells, thimerosal-induced [Ca(2+)](i) rises by causing phospholipase C-independent Ca(2+) release from the endoplasmic reticulum and Ca(2+) influx through non-L-type Ca(2+) channels. Thimerosal killed cells in a concentration-dependent manner through apoptosis.


Assuntos
Cálcio/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Neoplasias Bucais/patologia , Timerosal/toxicidade , Apoptose/efeitos dos fármacos , Bloqueadores dos Canais de Cálcio/farmacologia , Canais de Cálcio Tipo L/efeitos dos fármacos , Linhagem Celular Tumoral , Quelantes/farmacologia , Relação Dose-Resposta a Droga , Ácido Egtázico/análogos & derivados , Ácido Egtázico/farmacologia , Retículo Endoplasmático/efeitos dos fármacos , Retículo Endoplasmático/patologia , Inibidores Enzimáticos/farmacologia , Estrenos/farmacologia , Humanos , Inibidores de Fosfodiesterase/farmacologia , Proteína Quinase C/antagonistas & inibidores , Pirrolidinonas/farmacologia , Tapsigargina/farmacologia , Fosfolipases Tipo C/antagonistas & inibidores , Fosfolipases Tipo C/metabolismo
16.
J Hazard Mater ; 163(2-3): 916-21, 2009 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-18755540

RESUMO

This investigation elucidates the pozzolanic behavior of waste glass blended cement (WGBC) paste used in thin film transistor liquid crystal displays (TFT-LCD). X-ray diffraction (XRD) results demonstrate that the TFT-LCD waste glass was entirely non-crystalline. The leaching concentrations of the clay and TFT-LCD waste glass all met the current regulatory thresholds of the Taiwan EPA. The pozzolanic strength activity indices of TFT-LCD waste glass at 28 days and 56 days were 89% and 92%, respectively. Accordingly, this material can be regarded as a good pozzolanic material. The amount of TFT-LCD waste glass that is mixed into WGBC pastes affects the strength of the pastes. The strength of the paste clearly declined as the amount of TFT-LCD waste glass increased. XRD patterns indicated that the major difference was the presence of hydrates of calcium silicate (CSH, 2 theta=32.1 degrees), aluminate and aluminosilicate, which was present in WGBC pastes. Portland cement may have increased the alkalinity of the solution and induced the decomposition of the glass phase network. WGBC pastes that contained 40% TFT-LCD waste glass have markedly lower gel/space ratios and exhibit less degree of hydration than ordinary Portland cement (OPC) pastes. The most satisfactory characteristics of the strength were observed when the mixing ratio of the TFT-LCD waste glass was 10%.


Assuntos
Conservação dos Recursos Naturais , Materiais de Construção , Vidro , Resíduos Industriais , Cristais Líquidos , Silicatos de Alumínio , Compostos de Cálcio , Silicatos
17.
J Environ Manage ; 88(4): 708-14, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17498863

RESUMO

The effects of nano-SiO(2) on three ash particle sizes in mortar were studied by replacing a portion of the cement with incinerated sewage sludge ash. Results indicate that the amount of water needed at standard consistency increased as more nano-SiO(2) was added. Moreover, a reduction in setting time became noticeable for smaller ash particle sizes. The compressive strength of the ash-cement mortar increased as more nano-SiO(2) was added. Additionally, with 2% nano-SiO(2) added and a cure length of 7 days, the compressive strength of the ash-cement mortar with 1 microm ash particle size was about 1.5 times better that of 75microm particle size. Further, nano-SiO(2) functioned to fill pores for ash-cement mortar with different ash particle sizes. However, the effects of this pore-filling varied with ash particle size. Higher amounts of nano-SiO(2) better influenced the ash-cement mortar with larger ash particle sizes.


Assuntos
Materiais de Construção , Nanotecnologia , Tamanho da Partícula , Esgotos , Dióxido de Silício/química , Microscopia Eletrônica de Varredura , Difração de Raios X
18.
Waste Manag ; 28(6): 1081-7, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17512717

RESUMO

Sewage sludge ash has been widely applied to cementitious materials. In this study, in order to determine effects of nano-SiO(2) additives on properties of sludge/fly ash mortar, different amounts of nano-SiO(2) were added to sludge/fly ash mortar specimens to investigate their physical properties and micro-structures. A water-binding ratio of 0.7 was assigned to the mix. Substitution amounts of 0%, 10%, 20%, and 30% of sludge/fly ash (1:1 ratio) were proposed. Moreover, 0%, 1%, 2%, and 3% of nano-SiO(2) was added to the mix. Tests, including SEM and compressive strength, were carried out on mortar specimens cured at 3, 7, and 28 days. Results showed that sludge/fly ash can make the crystals of cement hydration product finer. Moreover, crystals increased after nano-SiO(2) was added. Hence, nano-SiO(2) can improve the effects of sludge/fly ash on the hydration of mortar. Further, due to the low pozzolanic reaction active index of sludge ash, early compressive strengths of sludge/fly ash mortar were decreased. Yet, nano-SiO(2) could help produce hydration crystals, which implies that the addition of nano-SiO(2) to mortar can improve the influence of sludge/fly ash on the development of the early strength of the mortar.


Assuntos
Carbono/química , Materiais de Construção , Incineração , Material Particulado/química , Esgotos/química , Dióxido de Silício/química , Cinza de Carvão , Conservação dos Recursos Naturais , Microscopia Eletrônica , Nanopartículas
20.
Eur J Clin Nutr ; 60(10): 1207-13, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16670691

RESUMO

OBJECTIVE: To investigate whether vitamin B6 supplementation has a beneficial effect on immune responses in critically ill patients. DESIGN: A single-blind intervention study. SETTING: The study was performed at the Taichung Veterans General Hospital, the central part of Taiwan. SUBJECTS: Fifty-one subjects who stayed over 14 days in the intensive care unit completed the study. Subjects were not treated with any vitamin supplement before the intervention. INTERVENTIONS: Patients were randomly assigned to one of three groups, control (n = 20), a daily injection of 50 mg vitamin B-6 (B6 -50, n=15), or 100 mg vitamin B-6 (B6 -100, n = 16) for 14 days. MAIN OUTCOME MEASURES: Plasma pyridoxal 5'-phosphate (PLP), pyridoxal (PL), 4-pyridoxic acid (4-PA), erythrocyte alanine (EALT-AC) and aspartate (EAST-AC) aminotransaminase activity coefficient, and urinary 4-PA were measured. The levels of serum albumin, hemoglobin, hematocrit, high-sensitivity C-reactive protein (hs-CRP) and immune responses (white blood cell, neutrophils, total lymphocytes count (TLC), T- (CD3) and B-(CD19) lymphocytes, T-helper (CD4) and suppressor (CD8) cells) were determined. RESULTS: Plasma PLP, PL, 4-PA and urinary 4-PA concentrations significantly increased in two treated groups. T-lymphocyte and T-helper cell numbers and the percentage of T-suppressor cell significantly increased on day 14 in the B6 -50 group. Total lymphocyte count, T-helper and T-suppressor cell numbers, the percentage of T-lymphocyte cells and T-suppressors significantly increased in the B6 -100 group at the 14th day. There were no significant changes with respect to immune responses in the control group over 14 days. CONCLUSIONS: A large dose of vitamin B6 supplementation (50 or 100 mg/day) could compensate for the lack of responsiveness of plasma PLP to vitamin B6 intake, and further increase immune response of critically ill patients. SPONSORSHIP: This study was supported by the National Science Council, Taiwan, Republic of China (NSC-92-2320-B-040-026).


Assuntos
Estado Terminal , Imunidade Celular/efeitos dos fármacos , Fosfato de Piridoxal/sangue , Vitamina B 6/administração & dosagem , Vitamina B 6/imunologia , APACHE , Idoso , Alanina Transaminase/metabolismo , Aspartato Aminotransferases/metabolismo , Proteína C-Reativa/análise , Suplementos Nutricionais , Relação Dose-Resposta Imunológica , Eritrócitos/enzimologia , Feminino , Indicadores Básicos de Saúde , Hospitalização , Humanos , Linfócitos/imunologia , Masculino , Fosfato de Piridoxal/imunologia , Ácido Piridóxico/sangue , Ácido Piridóxico/urina , Albumina Sérica/análise
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