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61.
In this study, a real-time polymerase chain reaction (PCR)-based method was designed for the fast detection of Cronobacter spp. (a newly proposed genus formerly known as Enterobacter sakazakii) in infant formula. The real-time PCR was positively tested with 70 Cronobacter strains, including members of all the species of this genus, and 88 non-Cronobacter strains. This new PCR-based system was validated against the reference standard ISO/TS 22964: 2006 (ISO International Organization for Standardization 2006) using 70 food matrices including powdered infant formula, follow-up formula, and hydrolyzed cereals for infants. The detection limit of the technique was found to be of 1 cfu in 10 g of food, fulfilling the requirements of the European Commission. The time of analysis, which comprises around 3–6 days using the reference method, is considerably reduced to less than 24 h using the real-time PCR-based system hereby described, allowing food industry a faster release of the stocks for commercialization. Moreover, this method includes an internal amplification control, co-amplified during each PCR run to verify the results.  相似文献   
62.
The antimicrobial action of lactoferrin (LF)-derived peptides against Dekkera bruxellensis strains isolated from spoiled wines has been examined. The study included a fifteen-residue peptide (LfcinB(17-31)) derived from bovine lactoferricin B and a bovine LF pepsin hydrolysate (LFH). In vitro assays showed the inhibitory properties of LfcinB(17-31) on D. bruxellensis growth with IC(50) and MIC values in the micromolar range. Strains tested showed different sensitivity to the peptide. LfcinB(17-31) showed fungicidal properties towards all strains tested in laboratory growth medium. However, the extent of fungicidal activity was strain-dependent in must and wine, confirming the different antimicrobial action of peptides depending on both the food matrix and the target micro-organism. The binding of LfcinB(17-31) to D. bruxellensis cells was visualized by fluorescence microscopy and correlated with the fungicidal activity in the different matrixes. LfcinB(17-31) and LFH showed growth inhibitory properties in wine suggesting their potential use for spoilage control.  相似文献   
63.
Modified atmosphere packaging was used to prevent browning of minimally processed Conference pears, thus extending their shelf‐life. Colour changes as well as PPO activity were strongly influenced by the package headspace gas composition, which was determined by the packaging conditions. The initial colour of minimally processed pears was preserved for several weeks under cold storage in plastic pouches of very low O2 permeability and an initial atmosphere of 100% N2. A fractional conversion kinetic model fitted the experimental browning data with high accuracy. Colour degradation (ΔE*) of minimally processed pears occurred exponentially (kΔE = 0.019–0.077 day?1) owing to changes in lightness (kL = 0.021–0.07 day?1). In contrast, PPO exhibited a linear increase in activity which could be related to the availability of O2 in the package headspace. © 2002 Society of Chemical Industry  相似文献   
64.
The need for long-lasting and transformative therapies for mucopolysaccharidoses (MPS) cannot be understated. Currently, many forms of MPS lack a specific treatment and in other cases available therapies, such as enzyme replacement therapy (ERT), do not reach important areas such as the central nervous system (CNS). The advent of newborn screening procedures represents a major step forward in early identification and treatment of individuals with MPS. However, the treatment of brain disease in neuronopathic MPS has been a major challenge to date, mainly because the blood brain barrier (BBB) prevents penetration of the brain by large molecules, including enzymes. Over the last years several novel experimental therapies for neuronopathic MPS have been investigated. Gene therapy and gene editing constitute potentially curative treatments. However, despite recent progress in the field, several considerations should be taken into account. This review focuses on the state of the art of in vivo and ex vivo gene therapy-based approaches targeting the CNS in neuronopathic MPS, discusses clinical trials conducted to date, and provides a vision for the future implications of these therapies for the medical community. Recent advances in the field, as well as limitations relating to efficacy, potential toxicity, and immunogenicity, are also discussed.  相似文献   
65.
Methuosis is a type of programmed cell death in which the cytoplasm is occupied by fluid-filled vacuoles that originate from macropinosomes (cytoplasmic vacuolation). A few molecules have been reported to behave as methuosis inducers in cancer cell lines. Jaspine B (JB) is a natural anhydrous sphingolipid (SL) derivative reported to induce cytoplasmic vacuolation and cytotoxicity in several cancer cell lines. Here, we have investigated the mechanism and signalling pathways involved in the cytotoxicity induced by the natural sphingolipid Jaspine B (JB) in lung adenocarcinoma A549 cells, which harbor the G12S K-Ras mutant. The effect of JB on inducing cytoplasmic vacuolation and modifying cell viability was determined in A549 cells, as well as in mouse embryonic fibroblasts (MEF) lacking either the autophagy-related gene ATG5 or BAX/BAK genes. Apoptosis was analyzed by flow cytometry after annexin V/propidium iodide staining, in the presence and absence of z-VAD. Autophagy was monitored by LC3-II/GFP-LC3-II analysis, and autophagic flux experiments using protease inhibitors. Phase contrast, confocal, and transmission electron microscopy were used to monitor cytoplasmic vacuolation and the uptake of Lucifer yellow to assess macropinocyosis. We present evidence that cytoplasmic vacuolation and methuosis are involved in Jaspine B cytotoxicity over A549 cells and that activation of 5′ AMP-activated protein kinase (AMPK) could be involved in Jaspine-B-induced vacuolation, independently of the phosphatidylinositol 3-kinase/protein kinase B/mechanistic target of rapamycin complex 1 (PI3K/Akt/mTORC1) axis.  相似文献   
66.
Under the unmet need of efficient tumor‐targeting drugs for oncology, a recombinant version of the plant toxin ricin (the modular protein T22‐mRTA‐H6) is engineered to self‐assemble as protein‐only, CXCR4‐targeted nanoparticles. The soluble version of the construct self‐organizes as regular 11 nm planar entities that are highly cytotoxic in cultured CXCR4+ cancer cells upon short time exposure, with a determined IC50 in the nanomolar order of magnitude. The chemical inhibition of CXCR4 binding sites in exposed cells results in a dramatic reduction of the cytotoxic potency, proving the receptor‐dependent mechanism of cytotoxicity. The insoluble version of T22‐mRTA‐H6 is, contrarily, moderately active, indicating that free, nanostructured protein is the optimal drug form. In animal models of acute myeloid leukemia, T22‐mRTA‐H6 nanoparticles show an impressive and highly selective therapeutic effect, dramatically reducing the leukemia cells affectation of clinically relevant organs. Functionalized T22‐mRTA‐H6 nanoparticles are then promising prototypes of chemically homogeneous, highly potent antitumor nanostructured toxins for precise oncotherapies based on self‐mediated intracellular drug delivery.  相似文献   
67.
Liquid chromatography tandem mass spectrometry (LC-MS/MS) has been shown to be a viable tool for preclinical pharmacokinetic (PK) analysis of monoclonal antibody (mAb) therapeutics. This work describes free and total PK assays for the mAb PF-00547,659 in serum of ulcerative colitis patients in a First-In-Human study [Vermeire, S. et al. Gut2011, 60 (8), 1068-1075]. The assay to measure free PF-00547,659 used immuno-enrichment with a biotinylated anti-idiotypic antibody and streptavidin magnetic beads. The total assay used enrichment by protein G magnetic beads. Following elution of PF-00547,659 from the beads, addition of an extended sequence stable isotope labeled peptide and trypsin digestion, a proteotypic peptide derived from the CDR region of the light chain of PF-00547,659 was quantified by LC-MS/MS. The free assay had a calibration range from 7.03 ng/mL to 450 ng/mL. The assay was precise and accurate with interbatch imprecision <16.5%, and interbatch inaccuracy <13.7% at all concentrations investigated during assay qualification. Results from LC-MS/MS methodologies are compared with historical immunoassay data originally acquired during the course of the clinical study. PK parameter estimates were highly correlated between the two analytical approaches. This work provides precedence that immunoaffinity LC-MS/MS can effectively be used to measure the serum concentrations of mAb therapeutics in clinical studies.  相似文献   
68.
There are a large number of remedies in traditional medicine focused on relieving pain and inflammation. Flavanones have been a potential source in the search for leading compounds and biologically active components, and they have been the focus of much research and development in recent years. Eysenhardtia platycarpa is used in traditional medicine for the treatment of kidney diseases, bladder infections, and diabetes mellitus. Many compounds have been isolated from this plant, such as flavones, flavanones, phenolic compounds, triterpenoid acids, chalcones, sugars, and fatty acids, among others. In this paper, natural flavanone 1 (extracted from Eysenhardtia platycarpa) as lead compound and flavanones 1a–1d as its structural analogues were screened for anti-inflammatory activity using Molinspiration® and PASS Online in a computational study. The hydro alcoholic solutions (FS) of flavanones 1, 1a–1d (FS1, FS1a–FS1d) were also assayed to investigate their in vivo anti-inflammatory cutaneous effect using two experimental models, a rat ear edema induced by arachidonic acid (AA) and a mouse ear edema induced by 12-O-tetradecanoylphorbol acetate (TPA). Histological studies and analysis of pro-inflammatory cytokines TNF-α, IL-1β, and IL-6 were also assessed in AA-inflamed rat ear tissue. The results showed that the flavanone hydro alcoholic solutions (FS) caused edema inhibition in both evaluated models. This study suggests that the evaluated flavanones will be effective when used in the future in skin pathologies with inflammation, with the results showing 1b and 1d to be the best.  相似文献   
69.
Adaptive laboratory evolution works on the principle that populations of cells adapt to their environment over time by natural selection. In this work, we assess adaptive laboratory evolution as a tool to improve the performance of winemaking yeast strains, in order to cope with the challenges of global climate change. Specifically we addressed ethanol tolerance as a way to ensure good fermentation kinetics despite increasing sugar content in musts.  相似文献   
70.
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