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  • HV FILTER UNIT WITH FILLING BELL 10/PK - 151501205

    Tipo de documento:
    Certificado de calidad
    Número de lote:
    151501205
    Referencia del producto:
    SVHVB1010
    Nombre del producto:
    Unidad de filtración Sterivex-HV; 0,45 µm, PVDF, salida con campana, esterilizada por radiación
  • Differences in circulating concentrations of total, free and bound leptin relate to gender and body composition in adult humans. 11026527

    We describe a radioimmunoassay (RIA) for total leptin and a gel filtration procedure for the separation of free and bound leptin in human serum. The RIA, based on a locally prepared antibody, has a minimum detection limit of 0.9 ng/mL, a working range (CV 10%) of 2.5-50 ng/mL, inter-assay precision of 10.2, 7.2 and 8.9%CV at 7.9, 15.4 and 30.0 ng/mL, respectively, 94% recovery of exogenous leptin (range 81.1-120.6%), exhibited parallelism and demonstrated no significant cross-reactivity or interferences. A difference plot of results from this method and those from a commercially available kit (Linco Research) demonstrated satisfactory agreement up to concentrations of 50 ng/mL total leptin, with no significant bias. A gender-dependent correlation was obtained between body mass index (BMI) and total leptin (r = 0.91, P0.001, n = 75 for men; r = 0.79, P0.001, n = 72 for women), with women having higher leptin concentrations than men for any given BMI. Gel filtration studies (inter-assay precision: 4.7%CV, n = 18) demonstrated that a variable fraction (between 10% and 40%) of total leptin in serum was bound with high affinity (Keq = 1.0-1.45 x 10(9) L/mol) to a non-albumin, non-lipid macromolecule. Binding affinities were found to be similar irrespective of gender or fat mass. A significant positive correlation between free or bound leptin concentrations and BMI was obtained for both men and women (r = 0.87-0.94); free and bound leptin concentrations were also significantly higher in women (P0.01) than in men for any given BMI, and higher in obese (P0.01) than in lean individuals. We conclude that leptin 'resistance' associated with obesity cannot be accounted for by reduced free leptin concentrations in serum and that the methods described are suitable for the investigation of total, free and bound leptin for both clinical and research purposes.
    Tipo de documento:
    Referencia
    Referencia del producto:
    HL-81K
    Nombre del producto:
    Human Leptin RIA
  • HV FILTER UNIT WITH FILLING BELL 10/PK - 212108626

    Tipo de documento:
    Certificado de calidad
    Número de lote:
    212108626
    Referencia del producto:
    SVHVB1010
    Nombre del producto:
    Unidad de filtración Sterivex-HV; 0,45 µm, PVDF, salida con campana, esterilizada por radiación
  • Synaptoneurosome micromethod for fractionation of mouse and human brain, and primary neuronal cultures. 23017979

    Brain and primary neuron fractions enriched in synaptic terminals are important tools for neuroscientists in biochemical, neuroanatomical and physiological studies. We describe an annotated updated micro-method for preparing synaptoneurosomes (SNs) enriched in presynaptic and postsynaptic elements. An easy to follow, step-by-step, protocol is provided for making SNs from small amounts of mammalian brain tissue. This includes novel applications for material obtained from human neurosurgical procedures and primary rat neuronal cultures. Our updated method for preparing SNs using smaller amounts of tissue provides a valuable new tool and expands the capabilities of neuroscientists.
    Tipo de documento:
    Referencia
    Referencia del producto:
    03-100
    Nombre del producto:
    RIPAb+™ hnRNP M1-M4
  • HV FILTER UNIT WITH FILLING BELL 10/PK - 161600054

    Tipo de documento:
    Certificado de calidad
    Número de lote:
    161600054
    Referencia del producto:
    SVHVB1010
    Nombre del producto:
    Unidad de filtración Sterivex-HV; 0,45 µm, PVDF, salida con campana, esterilizada por radiación
  • Reduced sulfation of chondroitin sulfate but not heparan sulfate in kidneys of diabetic db/db mice. 23757342

    Heparan sulfate proteoglycans are hypothesized to contribute to the filtration barrier in kidney glomeruli and the glycocalyx of endothelial cells. To investigate potential changes in proteoglycans in diabetic kidney, we isolated glycosaminoglycans from kidney cortex from healthy db/+ and diabetic db/db mice. Disaccharide analysis of chondroitin sulfate revealed a significant decrease in the 4-O-sulfated disaccharides (D0a4) from 65% to 40%, whereas 6-O-sulfated disaccharides (D0a6) were reduced from 11% to 6%, with a corresponding increase in unsulfated disaccharides. In contrast, no structural differences were observed in heparan sulfate. Furthermore, no difference was found in the molar amount of glycosaminoglycans, or in the ratio of hyaluronan/heparan sulfate/chondroitin sulfate. Immunohistochemical staining for the heparan sulfate proteoglycan perlecan was similar in both types of material but reduced staining of 4-O-sulfated chondroitin and dermatan was observed in kidney sections from diabetic mice. In support of this, using qRT-PCR, a 53.5% decrease in the expression level of Chst-11 (chondroitin 4-O sulfotransferase) was demonstrated in diabetic kidney. These results suggest that changes in the sulfation of chondroitin need to be addressed in future studies on proteoglycans and kidney function in diabetes.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
    Nombre del producto:
    Múltiplo
  • Aerosolized ZnO nanoparticles induce toxicity in alveolar type II epithelial cells at the air-liquid interface. 21964423

    The majority of in vitro studies characterizing the impact of engineered nanoparticles (NPs) on cells that line the respiratory tract were conducted in cells exposed to NPs in suspension. This approach introduces processes that are unlikely to occur during inhaled NP exposures in vivo, such as the shedding of toxic doses of dissolved ions. ZnO NPs are used extensively and pose significant sources for human exposure. Exposures to airborne ZnO NPs can induce adverse effects, but the relevance of the dissolved Zn(2+) to the observed effects in vivo is still unclear. Our goal was to mimic in vivo exposures to airborne NPs and decipher the contribution of the intact NP from the contribution of the dissolved ions to airborne ZnO NP toxicity. We established the exposure of alveolar type II epithelial cells to aerosolized NPs at the air-liquid interface (ALI) and compared the impact of aerosolized ZnO NPs and NPs in suspension at the same cellular doses, measured as the number of particles per cell. By evaluating membrane integrity and cell viability 6 and 24 h post-exposure, we found that aerosolized NPs induced toxicity at the ALI at doses that were in the same order of magnitude as doses required to induce toxicity in submersed cultures. In addition, distinct patterns of oxidative stress were observed in the two exposure systems. These observations unravel the ability of airborne ZnO NPs to induce toxicity without the contribution of dissolved Zn(2+) and suggest distinct mechanisms at the ALI and in submersed cultures.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
  • Detection of Noroviruses in Tap Water in Japan by Means of a New Method for Concentrating Enteric Viruses in Large Volumes of Freshwater 15066808

    A virus concentration method using a cation-coated filter was developed for large-volume freshwater applications. Poliovirus type 1 (LSc 2ab Sabin strain) inoculated into 40 ml of MilliQ (ultrapure) water was adsorbed effectively to a negatively charged filter (Millipore HA, 0.45-µm pore size) coated with aluminum ions, 99% (range, 81 to 114%) of which were recovered by elution with 1.0 mM NaOH (pH 10.8) following an acid rinse with 0.5 mM H2SO4 (pH 3.0). More than 80% poliovirus recovery yields were obtained from 500-ml, 1,000-ml, and 10-liter MilliQ water samples and from tap water samples. This method, followed by TaqMan PCR detection, was applied to determine the presence of noroviruses in tap water in Tokyo, Japan. In a 14-month survey, 4 (4.1%) and 7 (7.1%) of 98 tap water samples (100 to 532 liters) contained a detectable amount of noroviruses of genotype 1 and genotype 2, respectively. This method was proved to be useful for surveying the occurrence of enteric viruses, including noroviruses, in large volumes of freshwater.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
  • Slit diaphragm protein Neph1 and its signaling: a novel therapeutic target for protection of podocytes against glomerular injury. 24554715

    Podocytes are specialized epithelial cells that are critical components of the glomerular filtration barrier, and their dysfunction leads to proteinuria and renal failure. Therefore, preserving podocyte function is therapeutically significant. In this study, we identified Neph1 signaling as a therapeutic target that upon inhibition prevented podocyte damage from a glomerular injury-inducing agent puromycin aminonucleoside (PAN). To specifically inhibit Neph1 signaling, we used a protein transduction approach, where the cytoplasmic domain of Neph1 (Neph1CD) tagged with a protein transduction domain trans-activator of transcription was transduced in cultured podocytes prior to treatment with PAN. The PAN-induced Neph1 phosphorylation was significantly reduced in Neph1CD-transduced cells; in addition, these cells were resistant to PAN-induced cytoskeletal damage. The biochemical analysis using subfractionation studies showed that unlike control cells Neph1 was retained in the lipid raft fractions in the transduced cells following treatment with PAN, indicating that transduction of Neph1CD in podocytes prevented PAN-induced mislocalization of Neph1. In accordance, the immunofluorescence analysis further suggested that Neph1CD-transduced cells had increased ability to retain endogenous Neph1 at the membrane in response to PAN-induced injury. Similar results were obtained when angiotensin was used as an injury-inducing agent. Consistent with these observations, maintaining high levels of Neph1 at the membrane using a podocyte cell line overexpressing chimeric Neph1 increased the ability of podocytes to resist PAN-induced injury and PAN-induced albumin leakage. Using a zebrafish in vivo PAN and adriamycin injury models, we further demonstrated the ability of transduced Neph1CD to preserve glomerular function. Collectively, these results support the conclusion that inhibiting Neph1 signaling is therapeutically significant in preventing podocyte damage from glomerular injury.
    Tipo de documento:
    Referencia
    Referencia del producto:
    Múltiplo
    Nombre del producto:
    Múltiplo