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Proliferation Test (proliferation + test)

Distribution by Scientific Domains

Medical Sciences	100%

Selected Abstracts

Cosmeceutical properties of levan produced by Zymomonas mobilis

INTERNATIONAL JOURNAL OF COSMETIC SCIENCE, Issue 3 2006
K. H. Kim
Levan, a polysaccharide that can be produced by both plants and micro-organisms, is a sugar polymer composed of fructose, with-2,6 linkages. Here, we have attempted to assess the possible use of levan produced by Zymomonas mobilis as a cosmeceutical ingredient. In service of this goal, we assessed a host of levan's properties, including its moisturizing effects, cell cytotoxicity, cell proliferation effects and anti-inflammation effects. Levan exhibited a moisturizing effect that was almost exactly the same as that evidenced by hyaluronic acid, as well as a similar cell proliferation effect in human fibroblast and keratinocyte cell lines. Moreover, in our cell proliferation test, which was conducted using bio-artificial skin constructed via 3-dimensional (3-D) culture after the induction of primary skin inflammation with 0.05% sodium lauryl sulphate (SLS), cell viability in the presence of levan (0.01 and 0.05 mg mL,1) was determined to be higher than cell viability in the absence of levan. In our anti-inflammation test, which was also conducted using 3-D artificial skin, and which involved the measurement of a quantity of secreted interleukin-1 (IL-1), a pre-inflammatory mediator induced by SLS, we determined that the quantity of IL-1 in the 3-D artificial skin treated with 0.01 and 0.05 mg mL,1 of levan was less than that registered in a skin sample that had been treated only with SLS. In this study, we determined that levan exerted an anti-inflammatory effect against inflammatory reactions to skin irritants, and also that levan exerted a cell-proliferative effect in bio-artificial skin, thereby indicating its potential applicability as a cosmeceutical agent. [source]

Beryllium sensitivity among workers at a Norwegian aluminum smelter,

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 7 2010
A.M. Nilsen PhD
Abstract Background Sensitivity to beryllium was investigated among workers at an aluminum smelter in Norway as a consequence of the findings in an occupational exposure survey. Methods Three hundred and sixty-two employees and 31 reference persons were tested for sensitization to beryllium with the beryllium lymphocyte proliferation test (BeLPT) based on specifications by the US Department of Energy in 2001. The results are reported as abnormal, borderline, or normal. Results One person (0.28%) from the aluminum smelter was found to have abnormal results in two separate blood samples and is sensitized to beryllium. Three other persons had one abnormal test that was not confirmed by a second test. One person in the reference group had one abnormal and one normal test result. No borderline samples were detected. None of the employees with one or more abnormal sample results had pot room asthma. The sensitized individual worked in a Soederberg line in 1972,1974. The beryllium concentration in the work atmosphere is estimated to have been similar as today (0.1,0.3,µg/m3), but work routines, etc. would cause higher total exposures. Conclusions Only one sensitized person of 362 is in line with what is found in other studies in the aluminum industry. The low number, compared with the beryllium handling industry, may be attributable to lower work atmosphere concentrations, beryllium speciation effects, or use of respiratory protection equipment. Pot room asthma does not appear to be associated with beryllium sensitization. Am. J. Ind. Med. 53:724,732, 2010. © 2010 Wiley-Liss, Inc. [source]

Beryllium-stimulated neopterin as a diagnostic adjunct in chronic beryllium disease

AMERICAN JOURNAL OF INDUSTRIAL MEDICINE, Issue 6 2003
Lisa A. Maier MD, MSPH
Abstract Background The diagnosis of chronic beryllium disease (CBD) relies on the beryllium lymphocyte proliferation test (BeLPT) to demonstrate a Be specific immune response. This test has improved early diagnosis, but cannot discriminate beryllium sensitization (BeS) from CBD. We previously found high neopterin levels in CBD patients' serum and questioned whether Be-stimulated neopterin production by peripheral blood cells in vitro might be useful in the diagnosis of CBD. Methods CBD, BeS, Be exposed workers without disease (Be-exp) normal controls and sarcoidosis subjects were enrolled. Peripheral blood mononuclear cells (PBMN) were cultured in the presence and absence of beryllium sulfate. Neopterin levels were determined from cell supernatants by enzyme linked immunosorbent assay (ELISA). Clinical evaluation of CBD subjects included chest radiography, pulmonary function testing, exercise testing, and the BeLPT. Results CBD patients produced higher levels of neopterin in both unstimulated and Be-stimulated conditions compared to all other subjects (P,<,0.0001). Unstimulated neopterin mononuclear cell levels overlapped among groups, however, Be-stimulated neopterin levels in CBD showed little overlap. Using a neopterin concentration of 2.5 ng/ml as a cutoff, Be-stimulated neopterin had a sensitivity of 80% and specificity of 100% for CBD and was able to differentiate CBD from BeS. Be-stimulated neopterin was inversely related to measures of pulmonary function, exercise capacity, and gas exchange. Conclusions Neopterin may be a useful diagnostic adjunct in the non-invasive assessment of CBD, differentiating CBD from BeS. Further studies will be required to determine how it performs in workplace screening. Am. J. Ind. Med. 43:592,601, 2003. © 2003 Wiley-Liss, Inc. [source]

Reactivity to sodium tetrachloropalladate (Na2[PdCl4]) compared to PdCl2 and NiCl2 in lymphocyte proliferation tests

ALLERGY, Issue 8 2009
J. Muris
Background:, For patch testing, replacement of the commonly used palladium dichloride (PdCl2) by sodium tetrachloropalladate (Na2[PdCl4]) was recently demonstrated to improve test accuracy and show a significant correlation with nickel (Ni), supporting the concept of cross-reactivity between Pd and Ni. A promising alternative to metal allergy patch testing is the in vitro lymphocyte proliferation test (LTT). Objectives:, The aim of this study was to test whether Na2[PdCl4] is also more sensitive for diagnosing Pd allergy with a standardized LTT. Patients/methods:, After determining optimal nontoxic and nonmitogenic concentrations for Na2[PdCl4], blood samples from 105 patients with clinical suspicion of metal allergy were tested with an LTT called memory lymphocyte immuno stimulation assay for Na2[PdCl4], PdCl2 and NiCl2. Reaction profiles were analysed for concordant positive reactions. Results:, Using the conventional cut-off of stimulation index , 3, 74.3% showed a positive reaction to NiCl2, 15.2% to PdCl2 and 28.6% to Na2[PdCl4]. All positive results to PdCl2 were covered by Na2[PdCl4]. From the 30 positive reactions to Na2[PdCl4], 26 (87%) were concordant for NiCl2 reactivity. Conclusion:, In LTT, the use of Na2[PdCl4] results in more positive reactions in Pd allergy testing which are in concordance with positive reactions to PdCl2 and NiCl2. [source]