Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.10.2 (focal adhesion kinase)
 44,029 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In this paper is proposed a simultaneous pre-concentration procedure using cloud point extraction for the determination of copper and zinc in food samples employing sequential multi-element flame atomic absorption spectrometry (FS-FAAS). The reagent used is 1-(2-pyridylazo)-2-naphthol (PAN) and the micellar phase is obtained using the non-ionic surfactant octylphenoxypolyethoxyethanol (Triton X-114) and centrifugation. The optimization step was performed using Box-Behnken design for three factors: solution pH, reagent concentration and buffer concentration. A multiple response function was established in order to get an experimental condition for simultaneous extraction of copper and zinc. Under the optimized experimental conditions, the method allows the determination of copper with a limit of detection (3sigma(b)/S, LOD) of 0.1 microg L(-1), precision expressed as relative standard deviation (R.S.D.) of 2.1 and 1.3% (N=10), for copper concentrations of 10 and 50 microg L(-1), respectively. Zinc is determined with a LOD of 0.15 microg L(-1) and precision as R.S.D. of 2.7 and 1.7% for concentrations of 10 and 50 microg L(-1), respectively. The enhancement factors obtained were 36 and 32 for copper and zinc, respectively. The accuracy was assessed by analysis of certified reference materials, namely, SRM 1567a - Wheat Flour and SRM 8433 - Corn Bran from National Institute of Standards & Technology and BCR 189-wholemeal flour from Institute of Reference Materials and Measurements. The method was applied to the determination of copper and zinc in oats, powdered chocolate, corn flour and wheat flour samples. The copper content in the samples analyzed varied from 1.14 to 3.28 microg g(-1) and zinc from 8.7 to 22.9 microg g(-1).
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PMID:Pre-concentration procedure for determination of copper and zinc in food samples by sequential multi-element flame atomic absorption spectrometry. 1880 1

Cytosolic alterations of calcium ion concentrations are an integral part of signal transduction. Similar functions have been hypothesized for other metal ions, in particular zinc (Zn(2+)), but this still awaits experimental verification. Zn(2+) is important for multiple cellular functions, especially in the immune system. Among other effects, it influences formation and secretion of pro-inflammatory cytokines, including TNF-alpha. Here we demonstrate that these effects are due to a physiological signaling system involving intracellular Zn(2+) signals. An increase of the intracellular zinc ion concentration occurs upon stimulation of human leukocytes with Escherichia coli, LPS, Pam(3)CSK(4), TNF-alpha, or insulin, predominantly in monocytes. Chelating this zinc signal with the membrane permeable zinc-specific chelator TPEN (N,N,N',N'-tetrakis-(2-pyridyl-methyl)ethylenediamine) completely blocks activation of LPS-induced signaling pathways involving p38 MAPK, ERK1/2, and NF-kappaB, and abrogates the release of proinflammatory cytokines, including TNF-alpha. This function of Zn(2+) is not limited to monocytes or even the immune system, but seems to be another generalized signaling system based on intracellular fluctuations of metal ion concentrations, acting parallel to Ca(2+).
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PMID:Zinc signals are essential for lipopolysaccharide-induced signal transduction in monocytes. 1894 Dec 40

A flow-injection, cold-vapor atomic absorption spectrophotometric method was developed for the determination of trace amounts of mercury in a proposed zinc ore concentrate Standard Reference Material (SRM 113b). The samples were digested with nitric and hydrochloric acids in closed Teflon digestion vessels. The experimental details for sample preparation and the flow injection method are discussed. The effect of matrix and various acid concentrations on the extraction and subsequent analysis of mercury were also studied. The method has a detection limit of 0.08 mug Hg/g in the sample. A certified reference material (CZN-1) was analyzed and the results obtained agreed well with the certified value.
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PMID:Determination of mercury in zinc ore concentrate reference materials using flow injection and cold-vapor atomic absorption spectrometry. 1896 8

The determination of manganese in the presence of iron and chromium by differential pulse voltammetry and fundamental harmonic alternating current voltammetry was compared, including the case of very high element concentration ratios. The voltammetric measurements were carried out using a stationary mercury electrode in ammonia-ammonium chloride buffer (pH 9.6). The analytical procedure was verified by the analysis of the standard reference materials Portland Cement BCS 372, Spectrographic Zinc Spelter NBS-SRM 631, Stainless Steel (AISI 321) NBS-SRM 121d and Highly Alloyed Steel Eurostandard 281-1. Precision and accuracy, expressed as relative standard deviation and relative error respectively, were of the order of 3-5%, while the detection limit for each element was around 1 x 10(-9) M. The standard addition technique improved the resolution of the voltammetric methods, within a maximum experimental error of 5%, even in the case of very high concentration ratios, that is outside the non-interference concentration ratios 69:1 >c(Fe):c(Mn) > 1:74; 35:1 > c(Fe):c(Cr) > 1:30 and 63:1 > c(Fe):c(Mn) > 1:65; 32:1 > c(Fe):c(Cr) > 1:31 for the differential pulse and alternating current techniques respectively, extrapolating the linear section of the i(p) vs. concentration analytical calibration function for the element present at the lowest concentration. In contrast, the element with the greatest concentration was determined by the relevant calibration curve.
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PMID:Trace level voltammetric determination of manganese, iron and chromium in real samples in the presence of each other. 1896 61

Methods for the direct determination of iron and zinc in different components of cow milk (whole milk, non fat milk and whey milk) by flame atomic absorption spectrometry (FAAS) were performed using two nebulizers (nebulizer of platinum with a glass impact bead and a high performance nebulizer). The non fat milk and the whey milk were obtained by physical procedures (centrifugation and ultracentrifugation) in absence of chemical treatment. A limit of detection of 0.024 and 0.007 mug ml(-1) for iron and zinc, respectively, were obtained by using a high performance nebulizer. The precision obtained varied between 1.4-4.0% and 0.4-1.9% for iron and zinc, respectively. The accuracy of the methods was studied with the analysis of SRM-1549 and A-11 non fat milk reference materials. The methods were applied to ten cow milk samples. Dates about the distribution of iron and zinc into the different components of cow milk were present.
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PMID:Direct determination of Fe and Zn in different components of cow milk by FAAS with a high performance nebulizer. 1896 10

A simple flow injection on-line dilution procedure with detection by inductively coupled plasma mass spectrometry (ICP-MS) was developed for the determination of copper, zinc, arsenic, lead, selenium, nickel and molybdenum in human urine. Matrix effects were minimized by employing a dilution factor of 16.5 with on-line standard addition, and (103)Rh was used as internal standard to compensate for signal fluctuation. The procedure was validated by the analysis of two standard reference materials SRM 2670 (NIST) and Seronormtrade mark Trace Elements in Urine. Recovery experiments were performed by spiking the reference materials as well as artificial urine. The detection limits (mug l(-1)) were 0.12,0.96,0.30,0.09,0.45,0.08,0.09, and the precisions (RSD,%) were 2.6,2.3,3.0,3.7,3.7,4.9,2.8 for Cu, Zn, As, Pb, Se, Ni and Mo, respectively. The procedure was applied to the analysis of 41 human urine samples. No correlations between the concentrations of the elements were observed.
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PMID:Flow injection on-line dilution for multi-element determination in human urine with detection by inductively coupled plasma mass spectrometry. 1896 53

A solid phase extraction procedure based on biosorption of copper(II), lead(II), zinc(II), iron(III), nickel(II) and cobalt(II) ions on Aspergillus fumigatus immobilized Diaion HP-2MG has been investigated. The analytical conditions including amounts of A. fumigatus, eluent type, flow rates of sample and eluent solutions were examined. Good recoveries were obtained to the spiked natural waters. The influences of the concomitant ions on the retentions of the analytes were also examined. The detection limits (3sigma, N=11) were 0.30mugl(-1) for copper, 0.32mugl(-1) for iron, 0.41mugl(-1) for zinc, 0.52mugl(-1) for lead, 0.59mugl(-1) for nickel and 0.72mugl(-1) for cobalt. The relative standard deviations of the procedure were below 7%. The validation of the presented procedure is performed by the analysis of three standard reference materials (NRCC-SLRS 4 Riverine Water, SRM 1515 Apple leaves and GBW 07605 Tea). The procedure was successfully applied for the determination of analyte ions in natural waters microwave digested samples including street dust, tomato paste, black tea, etc.
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PMID:Biosorption of heavy metals on Aspergillus fumigatus immobilized Diaion HP-2MG resin for their atomic absorption spectrometric determinations. 1897 Aug 90

Endometrial serous carcinomas (ESC) constitute only approximately 10% of endometrial cancers, but have a substantially higher case-fatality rate than their more common endometrioid counterparts. The precise composite of factors driving endometrial serous carcinogenesis and progression remain largely unknown, but we attempt to review the current state of knowledge in this report. ESC probably do not evolve through a single pathway, and their underlying molecular events probably occur early in their evolution. TP53 gene mutations occur in 22.7 to 96% of cases, and p53 protein overexpression is seen in approximately 76%. By gene expression profiling, p16 is upregulated in ESC significantly above both normal endometrial cells and endometrioid carcinomas, and 92-100% of cases display diffuse expression of the p16 protein by immunohistochemistry (IHC). Together, these findings suggest dysregulation of both the p16(INKA)/Cyclin D-CDK/pRb-E2F and the ARF-MDM2-p53 cell cycle pathways in ESC. By IHC, HER2/neu is overexpressed (2+ or 3+) in approximately 32.1% of ESC, and approximately 54.5% of cases scored as 2+ or 3+ by IHC display c-erbB2 gene amplification as assessed by fluorescent in situ hybridization. Genetic instability, typically manifested as loss of heterozygosity in multiple chromosomes, is a common feature of ESC, and one study found loss of heterozygosity at 1p32-33 in 63% of cases. A subset of ESC display protein expression patterns that are characteristic of high grade endometrial carcinomas, including loss of the metastasis suppressor CD82 (KAI-1) and epithelial-to-mesenchymal transformation, the latter manifested as E-cadherin downregulation, P-cadherin upregulation, and expression of epithelial-to-mesenchymal transformation-related molecules such as zinc-finger E-box-binding homeobox 1 (ZEB1) and focal adhesion kinase. Preliminary data suggests differential patterns of expression in ESC of some isoforms of claudins, proteases, the tumor invasiveness and progression-associated oncofetal protein insulin-like growth factor II mRNA-binding protein 3 (IMP3), as well as a variety of other molecules. At the morphologic level, evidence that indicates that endometrial glandular dysplasia (EmGD) is the most likely morphologically recognizable precursor lesion to ESC is presented. We advocate use of the term endometrial intraepithelial carcinoma (EIC, or its other appellations) only as a morphologic descriptor and never as a diagnostic/pathologic statement of biologic potential. Given its potential for extrauterine extension, we consider the lesions described as EIC, when present in isolation, as examples of localized ESC, and patients should be managed as such. Morphologically normal, p53 immunoreactive endometrial cells (the so-called "p53 signatures"), show a statistically significant association with ESC, display p53 mutations in a significant subset, and form the start of a progression model, outlined herein, from p53 signatures to EmGD to localized ESC to the more conventionally invasive neoplasm. The identification of a morphologically-recognizable precursor holds the promise of early detection of ESC, with the attendant reduction in its overall associated mortality rate. Deciphering the molecular basis for endometrial serous carcinogenesis should uncover potential targets for diagnosis, therapy, and/or disease surveillance.
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PMID:Insights into endometrial serous carcinogenesis and progression. 1929 1

A method of ultrasound-assisted digestion followed by inductively coupled plasma optical emission spectrometry (ICP-OES) used for the determination of trace element (chromium, copper, lead, nickel, vanadium and zinc) concentrations in fly ash samples was developed. All the measurements were performed in robust plasma conditions. Ultrasound-assisted digestion procedures using digestion solutions of aqua regia and hydrofluoric acid (HF) resulted in recovery rates of over 80% for all the analyte elements. Ultrasound-assisted two-step digestion with digestion solutions of 6mL of HNO(3) (Step 1) and 3mL of HNO(3)+3mL of HF (Step 2) resulted in recovery rates of over 92% for all the analyte elements with one exception, chromium, which had a recovery of about 85%. The analysis of SRM 1633b showed that the two-step ultrasound-assisted digestion method developed resulted in chromium, copper, nickel and zinc concentrations higher than the microwave digestion method standardized by the United States Environmental Protection Agency (USEPA method 3052). This is the very first time when a digestion method using ultrasound resulted in higher efficiency than microwave (USEPA method 3052) for chromium and nickel in very hard to dissolve samples. The major advantages of the ultrasound-assisted digestion over microwave digestion is the high treatment rate (about 30 samples simultaneously with a sonication time of 18min) and the possibility to use new sample vessels without a significant increase in costs.
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PMID:The determination of trace element concentrations in fly ash samples using ultrasound-assisted digestion followed with inductively coupled plasma optical emission spectrometry. 1934 5

The mechanism that is responsible for mature neutrophil overproduction in the chronic phase (CP) of chronic myeloid leukemia (CML), a neoplastic disease of hematopoietic stem cells carrying a constitutively active tyrosine kinase BCR-ABL, remains obscure. In this study, microarray analysis revealed that c-Jun, a monopoiesis-promoting transcription factor, was downregulated in CML neutrophils. BCR-ABL directly inhibited c-Jun expression, as c-Jun downregulation in primary CML neutrophils and in the CML blast cell lines, KCL22 and K562, was reversed by the tyrosine kinase inhibitor imatinib. We established a myeloid differentiation model in KCL22 cells using zinc-inducible CCAAT/enhancer-binding protein (C/EBP)alpha (KCL22/alpha). Myeloid differentiation was observed in C/EBP-induced KCL22/alpha cells. Imatinib-induced c-Jun upregulation promoted the monocytic differentiation of KCL22/alpha cells. c-Jun knockdown in KCL22/alpha cells by a short interfering RNA redirected their differentiation from the monocytic to the neutrophilic lineage, even after imatinib treatment. A blockade of PI3K-Akt signaling with an Akt inhibitor upregulated c-Jun and induced the monocytic differentiation of KCL22, K562, and C/EBP-induced KCL22/alpha cells. Thus, BCR-ABL downregulates c-Jun expression by activating the PI3K-Akt pathway during CML-CP, thereby allowing C/EBPs to promote neutrophil differentiation.
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PMID:BCR-ABL promotes neutrophil differentiation in the chronic phase of chronic myeloid leukemia by downregulating c-Jun expression. 1935 99


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