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  • 1
    Electronic Resource
    Electronic Resource
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 114 (2001), S. 1575-1581 
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: We present a method for the design of laser fields to control a selective preparation of enantiomers from their racemate. An expression for two components of the laser pulses [EX(t) and EY(t)] propagating along the Z axis is derived using a locally optimized control theory in the density operator formalism. This expression was applied to a selective preparation of (R-, L-) enantiomers from preoriented phosphinotioic acid (H2POSH) at low temperatures. The target operator was set for the populations to be localized in one side of the double-well potential. First, a simple one-dimensional model was treated. Then, a two-dimensional model in which a free rotation around the preoriented torsional axis is included was briefly considered. In the one-dimensional model, almost complete preparation of the enantiomers was obtained. The optimal electric field consists of a sequence of two linearly polarized pulses with the same phases but with different magnitudes. This means that the resultant electric field is linearly polarized with the polarization for obtaining the R-form nearly parallel to its S–H bond. The optimal electric field transfers the L-form into the R-form while suppressing the reverse process. In the two-dimensional model, the enantiomer selective preparation is controlled by a sequence of circularly polarized pulses. © 2001 American Institute of Physics.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    Histopathology 37 (2000), S. 0 
    ISSN: 1365-2559
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Science Ltd
    British journal of dermatology 149 (2003), S. 0 
    ISSN: 1365-2133
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Medicine
    Notes: Summary  Background The most characteristic change in psoriasis vulgaris is markedly increased, persistent keratinocyte proliferation. The underlying mechanism of excessive epidermal growth is controversial. We previously found and reported that T-cadherin was expressed in keratinocytes and confined to the basal layer of mouse and human skin. Invasive cutaneous squamous cell carcinoma showed a loss of T-cadherin expression. Another study showed that T-cadherin was a negative growth regulator of epidermal growth factor in T-cadherin transfectant neuroblastoma cells.Objectives  To obtain insight into the role of T-cadherin in keratinocyte proliferation and to investigate further the pathogenesis of psoriasis vulgaris, we examined the expression of T-cadherin, as well as E- and P-cadherin, in psoriasis vulgaris.Methods  Four untreated active psoriatic skin samples from psoriasis vulgaris patients and four normal human skin samples from plastic surgery were collected, cryosectioned and immunohistochemically stained by antihuman T-, P- and E-cadherin antibodies. Further, the immunofluorescence intensities of T- and P-cadherin on the basal layer of the epidermis were quantitatively measured by the histogram function of LSM 510 software installed in a Zeiss laser scanning confocal microscope. The data were statistically analysed by Student's t-test.Results  It was observed that T-cadherin was weakly and discontinuously expressed on the basal layer of psoriatic skin, while it was intensively expressed on all basal keratinocytes in normal human skin. In contrast, P-cadherin was strongly expressed throughout the entire epidermal layer in psoriatic skin samples, although its expression is restricted to the basal cell layer in normal human skin. There were no obvious differences in E-cadherin expression between normal human skin and psoriatic skin. Statistical analyses showed that the immunofluorescence intensity of T-cadherin in the basal cell layer of psoriatic skin (35 ± 9·08) was significantly decreased compared with that in normal human skin (131·75 ± 3·49, P = 2·46 × 10−6). There was a significant increase (P = 0·00139) in the immunofluorescence intensity of P-cadherin in the basal layer of psoriatic skin (68·25 ± 12·13) compared with normal human skin (26 ± 4·90).Conclusions  The present study demonstrates that there is downregulation of T-cadherin expression and upregulation of P-cadherin expression in psoriatic skin, which are considered to be involved in the hyperproliferation of keratinocytes in psoriasis vulgaris.
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1432-1750
    Keywords: Key words: Lymphocytes—Subset—CD4—CD8—Bronchoalveolar lavage—Open lung biopsy.
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. This study was designed to evaluate the distribution of lymphocyte subsets in lung specimens that were obtained by open-lung biopsy from 8 patients with idiopathic nonspecific interstitial pneumonia/fibrosis (NSIP) and 10 patients with pulmonary fibrosis associated with collagen vascular disorders (PF-CVD). Distributions of B lymphocytes, CD4-positive T lymphocytes, and CD8-positive T lymphocytes were evaluated immunohistochemically and compared with the cell composition in BALF. Correlation between CD4/CD8 ratios in bronchoalveolar lavage fluids (BALF) and CD4/CD8 ratios in lung tissues was also examined. B lymphocytes were mostly restricted in lymphoid follicles. CD4-positive T lymphocytes were observed inside and around lymphoid follicles and in the thick fibrotic wall of reconstructed alveoli with fibrosis. In contrast, CD8-positive T lymphocytes were diffusely distributed, especially in relatively thin alveoli. Correlation was weak between CD4/CD8 ratios in lung tissue and CD4/CD8 ratios in BALF. However, even in patients with very low CD4/CD8 ratios in BALF, many CD4 lymphocytes were observed in lung tissues, suggesting that CD8-positive lymphocytes diffusely distributed in thin alveolar architecture were more easily recovered in BALF than CD4-positive lymphocytes. Therefore, a low CD4/CD8 ratio in BALF may indicate that the alveolar structure was not severely reconstructed by fibrosis. This is the first report that compared lymphocyte subsets in lung tissues and in BALF.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-1750
    Keywords: Key words: Autoantibody—Cytokeratin 18—Idiopathic pulmonary fibrosis—Immune complexes
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract. In this study, we hypothesize that anti-cytokeratin 18 (CK18) antibody and CK18:anti-CK18 immune complex increase in sera in patients with idiopathic pulmonary fibrosis (IPF). To prove the existence of anti-CK18 antibodies in patients' sera, bovine CK18 was stained with patients' sera using a Western blotting. In patients with IPF, anti-CK18 antibodies were clearly demonstrated in sera by Western blotting. Then, we tried to establish an enzyme-linked immunosorbent assay (ELISA) to quantify anti-CK18 antibodies and CK18:anti-CK18 immune complexes in sera of patients with IPF. Levels of anti-human CK18 antibodies in sera of patients with IPF (0.81 ± 0.31, mean ± SD) measured by ELISA were significantly high compared with that of normal volunteers (0.45 ± 0.06, p 〈 0.01). In addition, levels of CK18:anti-CK18 antibody complexes in patients' sera (0.64 ± 0.35, man ± SD) significantly increased compared with those of normal subjects (0.40 ± 0.10, p 〈 0.01). These results suggest that anti-CK18 antibody and its immune complex may have played a role in the process of lung injury in IPF.
    Type of Medium: Electronic Resource
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  • 6
    ISSN: 1432-2307
    Keywords: Key words Cyclin D1 ; Skin cancer ; Differentiation ; Sun exposure ; Aging
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract  Although the overexpression of cyclin D1 has been believed to play important roles in neoplastic transformation of some tumors, little is known about the function of cyclin D1 protein in carcinogenesis in human skin. A total of 307 patients with nonmelanocytic skin cancer, being 46 with Bowen’s disease (BOD), 134 with squamous cell carcinoma (SCC) and 127 with basal cell carcinoma (BCC), were investigated immunohistochemically using monoclonal antibody to cyclin D1 by the LSAB method, to assess the expression of cyclin D1 in skin cancer including its precursors. The positive rates of cyclin D1 immunostaining in BOD, SCC and BCC were 63.0%, 69.4% and 54.3%, respectively. The positive rates in dysplasia adjoining BOD, SCC and BCC were 43.6%, 67.9% and 59.8%, respectively. In morphologically normal skin, however, only 2 cases, 1 of SCC and 1 of BCC, exhibited positive staining. These findings suggested that overexpression of cyclin D1 is an early event in dysplastic lesions of skin. Overexpression of cyclin D1 was related to sun exposure, especially in dysplasia of SCC. The score for cyclin D1 expression in dysplasia of BCC was correlated with age. Expression of cyclin D1 markedly increased from normal skin through dysplasia to BOD, but was not significantly related to the degree of SCC differentiation. These findings demonstrate that the effect of cyclin D1 overexpression is restricted to proliferation of cells, so that they gain a growth advantage, but their differentiation is not increased. Comparison with the results for p53 protein expression in these tumors, a significant correlation with cyclin D1 expression was found in dysplasia in BOD and SCC, and in patients with BCC who were less than 74 years old. These findings suggested the hypothesis that prior aberrant p53 expression may affect or regulate the overexpression of cyclin D1.
    Type of Medium: Electronic Resource
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