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21.
Radiation therapy for cancer permanently damages tissue in the line of treatment. This study sought to establish a serum-free protocol to evaluate the growth of irradiated fibroblasts and to analyze the levels of basic fibroblast growth factor (bFGF) and transforming growth factor-beta (TGF-beta) compared with normal fibroblasts. One irradiated cell line of human dermal fibroblasts was established from an intraoperative specimen obtained from a patient who had undergone radiation therapy for head and neck cancer. Irradiated and normal fibroblasts were then plated in UltraCULTURE (serum and growth factor free), modified Webber's medium (bFGF 50 ng/ml, insulin-like growth factor 100 ng/ml), and Dulbecco's Modified Eagle Medium with 10% fetal bovine serum (serum with undefined basal growth factors). Irradiated cells were also seeded in UltraCULTURE with 50 and 100 ng/ml of bFGF. Cell counts were performed at 0, 1, 3, 5, and 7 days, and cell supernatants were assayed for bFGF and TGF-beta. Irradiated and normal fibroblasts exhibited stronger growth in modified Webber's medium than in Dulbecco's Modified Eagle Medium with 10% fetal bovine serum. Growth of irradiated fibroblasts under bFGF modulation was similar to their growth in Webber's medium. Furthermore, irradiated fibroblasts remained viable in a serum-free and growth factor-free environment for at least 7 days; however, their growth and autocrine growth factor production was less than that of normal cells. This confirms the results of previous studies suggesting that cells from irradiated tissue undergo cellular changes. This study provides an effective model for the first-line evaluation of agents to improve wound healing, and it helps to establish standard levels of bFGF and TGF-beta production for irradiated fibroblasts.  相似文献   
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The effects of a 24 hrs pulse conditioning with GA3 or BA on the lipoxygenase activity and the expression of the lipoxygenase gene were studied in senescing cut leaves of Zantedeschia aethiopica Spr. and Hosta ‘Undulata Erromena’, respectively. The GA3 treatment in Zantedeschia and the BA treatment in Hosta prevented increases the activity of lipoxygenase in senescing cut leaves. No effects of growth regulators on the lipoxygenase gene expression were observed in cut leaves of both species.  相似文献   
23.
Photosensitizing dyes are used in fluorescence diagnostics and photodynamic therapy (PDT). These usually hematoporphyrin derivatives (HpD) accumulate preferentially within neoplastic tissues. HpD is a mixture of ether and ester linked porphyrins. Its partially purified form is known under the commercial name of photofrin II (PII). PII emission spectra were studied in a hydrophilic (PBS) and a lipophilic (PC liposomes) environment. Red shift was observed in their emission maxima from 615 nm in buffer solution to 635 nm in lipid. Identical red shift was obtained when the intracellular fluorescence of two cancer cell lines, MCF 7 and Jurkat, incubated with PII was investigated. Thus, intramembrane localization of PII may be suggested. As determined from the total fluorescence intensity, the uptake of PII was only slightly higher for Jurkat than for MCF 7 cells. Nevertheless the kinetics of the uptake was found to be different for both cell lines.  相似文献   
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RNA structure in the influenza A virus (IAV) has been the focus of several studies that have shown connections between conserved secondary structure motifs and their biological function in the virus replication cycle. Questions have arisen on how to best recognize and understand the pandemic properties of IAV strains from an RNA perspective, but determination of the RNA secondary structure has been challenging. Herein, we used chemical mapping to determine the secondary structure of segment 8 viral RNA (vRNA) of the pandemic A/California/04/2009 (H1N1) strain of IAV. Additionally, this long, naturally occurring RNA served as a model to evaluate RNA mapping with 4-thiouridine (4sU) crosslinking. We explored 4-thiouridine as a probe of nucleotides in close proximity, through its incorporation into newly transcribed RNA and subsequent photoactivation. RNA secondary structural features both universal to type A strains and unique to the A/California/04/2009 (H1N1) strain were recognized. 4sU mapping confirmed and facilitated RNA structure prediction, according to several rules: 4sU photocross-linking forms efficiently in the double-stranded region of RNA with some flexibility, in the ends of helices, and across bulges and loops when their structural mobility is permitted. This method highlighted three-dimensional properties of segment 8 vRNA secondary structure motifs and allowed to propose several long-range three-dimensional interactions. 4sU mapping combined with chemical mapping and bioinformatic analysis could be used to enhance the RNA structure determination as well as recognition of target regions for antisense strategies or viral RNA detection.  相似文献   
26.
A high-performance liquid chromatographic method is described for determination of lidocaine (2-(dietyloamino)-N-(2,6-dimetylofenylo) acetamid) and its metabolite, monoethylglycine xylidide (MEGX), in human serum containing various concentration of bilirubin. Lidocaine and its metabolite were extracted from human serum using dichloromethane. After separation of the layers and freezing at -32 degrees C, the organic layer was decanted and evaporated under a stream of nitrogen. The sample was dissolved in the mobile phase (12% acetonitrile in 15mM potassium dihydrogen orthophosphate, pH 3.0), and after separation on a Supelcosil LC-8-DB column, the analytes were measured by ultraviolet detection at 205nm. Trimethoprim (TMP) was used as the internal standard. The recovery of the examined analytes ranged from 95.7 to 97.9% for lidocaine and from 98.0 to 99.9% for MEGX. The lower limit of quantification (LLOQ) was established at 200microg/l for lidocaine and at 10microg/l for MEGX. The choice of suitable conditions for chromatographic separation of lidocaine and its metabolite MEGX allowed the elimination of the influence of endogenous bilirubin on the result of analysis.  相似文献   
27.
Argireline-containing cosmetics attract public interest due to their confirmed reduction of facial wrinkles. Argireline is a peptide that works by inhibiting the release of neurotransmitters in the neuromuscular junction, producing a botox-like effect. Therefore, it is used as a safe needle-free alternative to botox treatment. In this work we investigated the presence of Argireline in cosmetic creams and sera by application of reversed phase liquid chromatography and tandem mass spectrometry (RP-HPLC/MS and MS/MS). The analysis revealed the presence of argireline and its oxidized form in several different cosmetics. The methionine residue in Argireline sequence was indicated as oxidation point according to neutral loss MS studies. The developed sample preparation strategy minimizes and monitors methionine oxidation, bringing to our attention the question of impact of ingredients on the stability of cosmetic product.  相似文献   
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A 13 year old Danish/Swedish Farmdog from Denmark was evaluated in a veterinary clinic in Warsaw, Poland for evaluation of an orthopedic problem. Radiographs revealed spondylosis and degenerative vertebral disease, which responded to treatment with anti-inflammatory medications. A predominance of hyposegmented neutrophils and eosinophils containing condensed chromatin and normal cytoplasm were identified on a routine CBC. Follow-up blood film evaluations over the course of 12 months confirmed that the hyposegmented granulocytes persisted. The majority of neutrophils contained Grade 2 nuclei (slightly indented), and the mean nuclear score varied from 1.9 to 2.3. Pelger-Huët anomaly (PHA), presumably congenital, was diagnosed based on persistent hyposegmented granulocytes in the absence of an underlying cause for acquired PHA; genetically related dogs were unavailable for testing to confirm vertical transmission. To the authors' knowledge this is the first report of PHA in a Danish/Swedish Farmdog.  相似文献   
30.
Here we present a simple and rapid method for the construction of phosphonic peptide mimetic inhibitor libraries-products of Ugi and Passerini multicomponent condensations-leading to the selection of new biologically active phosphonic pseudopeptides. As the starting isonitriles, 1-isocyanoalkylphosphonate diaryl ester derivatives were applied. The structure of the synthesized inhibitors was designed to target human neutrophil elastase, a serine protease whose uncontrolled activity may lead to development of several pathophysiological states such as rheumatoid arthritis, cystic fibrosis or tumor growth and invasion. After screening the inhibitory activity of our constructed libraries, the most active compounds were synthesized as single molecules. One of the obtained inhibitors, Cbz-Met-O-Met-Val(P)(OC(6)H(4)-p-Cl)(2), displayed apparent second-order inhibition value at 40,105M(-1)s(-1) as the diastereomers mixture. Inhibition potency and selectivity of action toward other serine proteases as well as the results of initial in vitro experiments regarding inhibitors influence on cancer cell proliferation are presented.  相似文献   
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