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1.
Environ Monit Assess ; 187(1): 4095, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25399119

RESUMO

Eighteen sites impacted by abandoned mine drainage (AMD) in Pennsylvania were sampled and measured for pH, acidity, alkalinity, metal ions, and sulfate. This study compared the accuracy of four acidity calculation methods with measured hot peroxide acidity and identified the most accurate calculation method for each site as a function of pH and sulfate concentration. Method E1 was the sum of proton and acidity based on total metal concentrations; method E2 added alkalinity; method E3 also accounted for aluminum speciation and temperature effects; and method E4 accounted for sulfate speciation. To evaluate errors between measured and predicted acidity, the Nash-Sutcliffe efficiency (NSE), the coefficient of determination (R (2)), and the root mean square error to standard deviation ratio (RSR) methods were applied. The error evaluation results show that E1, E2, E3, and E4 sites were most accurate at 0, 9, 4, and 5 of the sites, respectively. Sites where E2 was most accurate had pH greater than 4.0 and less than 400 mg/L of sulfate. Sites where E3 was most accurate had pH greater than 4.0 and sulfate greater than 400 mg/L with two exceptions. Sites where E4 was most accurate had pH less than 4.0 and more than 400 mg/L sulfate with one exception. The results indicate that acidity in AMD-affected streams can be accurately predicted by using pH, alkalinity, sulfate, Fe(II), Mn(II), and Al(III) concentrations in one or more of the identified equations, and that the appropriate equation for prediction can be selected based on pH and sulfate concentration.


Assuntos
Monitoramento Ambiental , Mineração , Poluentes Químicos da Água/química , Alumínio/análise , Concentração de Íons de Hidrogênio , Metais/análise , Pennsylvania , Rios/química , Sulfatos/análise , Poluentes Químicos da Água/análise
2.
Int J Clin Exp Pathol ; 6(10): 2157-67, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24133594

RESUMO

Immune complex-mediated complement activation through the classic pathway plays a key role in the pathogenesis of lupus nephritis (LN). C4d deposition in renal tissue reflects the prognosis of systemic lupus erythematosus (SLE). The aim of the current study is to investigate the pathogenesis and clinicopathologic significance of glomerular C4d deposition in LN. We retrospectively analyzed clinical and histopathological data of 20 SLE patients with renal biopsy-proven LN and 10 non-SLE renal biopsy samples as control. LN biopsies showed varying degrees of glomerular C4d staining associated with immune complex deposits, IgG (p = 0.015), C1q (p = 0.032) and C3 (p = 0.049). 7 LN biopsies had all of C4d, C1q and C3 deposits in their glomeruli, indicative of the activation of the classical pathway, whereas 2 LN biopsies had C4d and C3 deposits without accompanying C1q deposits, indicating the activation of the lectin pathway. Glomerular C4d deposition was correlated with the LN subtype (p < 0.001). In particular, a diffusely intense and coarsely granular pattern of C4d deposition in all glomeruli was detected in class V membranous LN. However, glomerular C4d deposition was correlated with neither disease activity of SLE nor histological activity and chronicity of LN. In conclusion, the activation of the lectin pathway as well as the classical pathway seems to play a crucial role in the pathogenesis of LN. Glomerular C4d staining could be helpful for diagnosing class V membranous LN, although glomerular C4d deposition does not reflect SLE disease activity and histological activity and chronicity.


Assuntos
Complemento C4b/metabolismo , Glomérulos Renais/metabolismo , Lectinas/metabolismo , Lúpus Eritematoso Sistêmico/metabolismo , Nefrite Lúpica/metabolismo , Fragmentos de Peptídeos/metabolismo , Adolescente , Adulto , Criança , Feminino , Humanos , Glomérulos Renais/imunologia , Glomérulos Renais/patologia , Lúpus Eritematoso Sistêmico/imunologia , Lúpus Eritematoso Sistêmico/patologia , Nefrite Lúpica/imunologia , Nefrite Lúpica/patologia , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
3.
Colloids Surf B Biointerfaces ; 82(1): 190-5, 2011 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-20850281

RESUMO

Pluronics with different structural compositions and properties are used for several applications, including drug delivery systems. We developed a binary mixing system with two Pluronics, L121/P123, as a nano-sized drug delivery carrier. The lamellar-forming Pluronic L121 (0.1 wt%) was incorporated with Pluronic P123 to produce nano-sized dispersions (in case of 0.1 and 0.5 wt% P123) with high stability due to Pluronic P123 and high solubilization capacity due to Pluronic L121. The binary systems were spherical and less than 200-nm diameter, with high thermodynamic stability (at least 2 weeks) in aqueous solution. The CMC of the binary system was located in the middle of the CMC of each polymer. In particular, the solubilization capacity of the binary system (0.1/0.1 wt%) was higher than mono-systems of P123. The main advantage of binary systems is overcoming limitations of mono systems to allow tailored mixing of block copolymers with different physicochemical characteristics. These nano-sized systems may have potential as anticancer drug delivery systems with simple preparation method, high stability, and high loading capacity.


Assuntos
Sistemas de Liberação de Medicamentos , Micelas , Nanopartículas/química , Tamanho da Partícula , Poloxâmero/química , Compostos Azo/química , Fluorescência , Nefelometria e Turbidimetria , Solubilidade , Soluções , Análise Espectral
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