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1.
Opt Lett ; 32(11): 1387-9, 2007 Jun 01.
Article in English | MEDLINE | ID: mdl-17546130

ABSTRACT

A room-temperature-operating vertical external cavity surface emitting laser is applied around 1550 nm to intracavity laser absorption spectroscopy analyzed by time-resolved Fourier-transform interferometry. At an equivalent path length of 15 km, the high-resolution spectrum of the semiconductor disk laser emission covers 17 nm simultaneously. A noise-equivalent absorption coefficient at 1 s averaging equal to 1.5 x 10(-10) cm(-1)Hz(-1/2) per spectral element is reported for 65 km, the longest path length employed.

2.
Opt Express ; 14(8): 3129-37, 2006 Apr 17.
Article in English | MEDLINE | ID: mdl-19516454

ABSTRACT

The authors report a compact and highly selective tunable filter using a Fabry-Perot resonator combining a bottom micromachined 3-pair-InP/air-gap Bragg reflector with a top photonic crystal slab mirror. It is based on the coupling between radiated vertical cavity modes and waveguided modes of the photonic crystal. The full-width at half maximum (FWHM) of the resonance, as measured by microreflectivity experiments, is close to 1.5nm (around 1.55 microm). The presence of the photonic crystal slab mirror results in a very compact resonator, with a limited number of layers. The demonstrator was tuned over a 20nm range for a 4V tuning voltage, the FWHM being kept below 2.5nm. Bending of membranes is a critical issue, and better results (FWHM=0.5nm) should be obtained on the same structure if this technological point is fixed.

3.
Int J Cosmet Sci ; 26(5): 221-9, 2004 Oct.
Article in English | MEDLINE | ID: mdl-18492134

ABSTRACT

The purpose of our studies was to verify efficacy and skin compatibility of a medical face care system containing 2% lactic acid (LA) as active ingredient in a specially designed vehicle (Follicle Targeting System) in adult subjects with mild acne vulgaris. The first study (46 patients) demonstrated superiority of 2% LA in comparison to 2% salicylic acid with respect to number of comedones and inflammatory lesions. The second study evaluated 90 patients receiving distinct combinations of face care products (Eucerin) Impure Skin, Hamburg, Germany), i.e. cleansing gel, facial tonic (2% LA) and cream gel (2% LA). All treatments were performed twice daily over a 12 weeks period. Lesion counts, cyanoacrylate biopsies and determination of quality of life by questionnaires were performed at different timepoints. A reduction of comedones by 56% corresponding to an 46% increase of quality of life index was demonstrated in patients applying cleansing gel, facial tonic and cream gel. For the first time we were able to show a significant improvement concerning the quality of life after using a new face care line. Especially adults with mild forms of acne may benefit from this effective skin care regimen.

4.
Lipids ; 36(3): 299-304, 2001 Mar.
Article in English | MEDLINE | ID: mdl-11337986

ABSTRACT

The stratum corneum (SC) requires ceramides, cholesterol, and fatty acids to provide the cutaneous permeability barrier. SC lipids can be analyzed by normal-phase high-performance thin-layer chromatography (HPTLC). However, without further analysis, some uncertainty remains about the molecular composition of lipids represented by every TLC band of an unknown sample. We therefore analyzed each ceramide band further by subjecting the isolated lipids to a direct coupling of reversed-phase high-performance liquid chromatography and electrospray ionization-mass spectrometry (HPLC/ESI-MS, or LC/MS). LC/MS analysis and ESI-MS/MS negative ion and collision-induced dissociation experiments revealed that ceramide band 4 contained not only N-(omega-OH-acyl)acyl-6-OH-sphingosine, Cer(EOH), but also N-(alpha-OH-acyl)-sphingosine. Band 5 exclusively contained N-acyl-6-OH-sphingosine. Our results demonstrate the benefit of LC/MS analysis for selective identification of human SC ceramides. Moreover, the combination of HPTLC for pre-separation and LC/MS for identification of lipids is an even more powerful tool for detailed ceramide analysis.


Subject(s)
Ceramides/analysis , Skin/chemistry , Chromatography, High Pressure Liquid , Female , Humans , Male , Mass Spectrometry , Spectrometry, Mass, Electrospray Ionization , Sphingosine/analysis
5.
J Pharm Biomed Anal ; 10(5): 323-8, 1992 May.
Article in English | MEDLINE | ID: mdl-1511033

ABSTRACT

For the measurement of the pharmacokinetic behaviour of moxonidine, 4-chloro-5-(2-imidazolin-2-yl-amino)-6-methoxy-2-methylpyrimidine, an extremely sensitive analytical method was needed. The GC-MS method developed is specific and reliably detects moxonidine plasma levels down to 40 pg ml-1. Using negative ion chemical ionization (NICI) the M- fragment of the ditrifluoromethyl benzamide derivative of moxonidine (m/z 721) and the [M-HCl]- fragment of the ditrifluoromethyl benzamide derivative of clonidine (internal standard, m/z 673) were monitored in the selected ion monitoring mode, ensuring a specific and sensitive detection of the compounds. The validation process carried out included assay precision, repeatability, linearity, accuracy, stability and estimation of the detection and determination limits. The plasma-level time-curves and pharmacokinetic parameters from two volunteers after oral administration of 0.2 mg moxonidine are presented and demonstrate the practicability of the method in, for example, clinical studies.


Subject(s)
Antihypertensive Agents/blood , Imidazoles/blood , Drug Stability , Gas Chromatography-Mass Spectrometry , Humans
6.
Zentralbl Gynakol ; 109(6): 347-52, 1987.
Article in German | MEDLINE | ID: mdl-3591067

ABSTRACT

In this paper it has been published about the interdisciplinary cooperation during the treatment of 143 pregnant women having heart diseases. In spite of a partial centralisation this number only 0.46 per cent of all deliveries in a period of 16 years. 32.1 per cent of the cases are congenital heart diseases and 46.2 per cent acquired heart diseases. In the acquired heart diseases mitral failures prevailed. Pacemakers have to be applied preventively only in 6.3 per cent. NYHA-stages did not impair during pregnancy. Vaginal operative delivery is compulsory only in two of seven cases heart diseases indicated a cesarean section. Consequent early get-up in the puerperium is important in NYHA-stages I-III. Maternal mortality was 0. Perinatal mortality was 0.7% (one child died antenatally).


Subject(s)
Patient Care Team , Pregnancy Complications, Cardiovascular/therapy , Cesarean Section , Female , Humans , Obstetric Labor Complications/therapy , Pregnancy , Prognosis
7.
Endokrinologie ; 72(3): 311-26, 1978 Nov.
Article in English | MEDLINE | ID: mdl-217678

ABSTRACT

Slices of an adreno-cortical adenoma which had been obtained at operation from an 11-year-old girl with clinical signs of virilism were incubated with each of the following steroids: [1,2-3H]progesterone, [4-14C]pregnenolone, [1,2-3H]testosterone, [4-14C]androstenedione and [7-3H]dehydroepiandrosterone, respectively. Isolation and identification of the free radioactive metabolites were achieved by gel column chromatography on Sephadex LH-20, thin-layer chromatography, radio gas chromatography and isotope dilution. After incubation of progesterone, the following metabolites were identified: 11beta-hydroxyprogesterone, 16alpha-hydroxyprogesterone, 17alpha-hydroxyprogesterone, 21-deoxycortisol, corticosterone and cortisol. Pregnenolone was metabolized to 17alpha-hydroxypregnenolone, progesterone, dehydroepiandrosterone, androstenedione and 11beta-hydroxyandrostenedione. When testosterone was used as substrate, 11beta-hydroxytestosterone, androstenedione and 11beta-hydroxyandrostenedione were found as metabolites, whereas androstenedione was metabolized to testosterone and 11beta-hydroxyandrostenedione. After incubation of dehydroepiandrosterone, only androstenedione and 11beta-hydroxyandrostenedione were isolated and identified. From these results, it appears that cortisol was formed in the adenoma tissue via 21-deoxycortisol and corticosterone. Delta4-3oxo steroids of the C19-series arose exclusively from pregnenolone via 17alpha-hydroxypregnenolone and dehydroepiandrosterone, and not from progesterone and 17alpha-hydroxyprogesterone. Calculated on the amounts of metabolites formed, the highest enzyme activities were those of the 11beta-hydroxylase and the 17alpha-hydroxylase. It is interesting to note that only traces of testosterone were detected after incubation of androstenedione, whereas testosterone yielded large amounts of androstenedione.


Subject(s)
Adenoma/metabolism , Adrenal Cortex Neoplasms/metabolism , Androstenedione/metabolism , Child , Chromatography, Gas , Dehydroepiandrosterone/metabolism , Female , Humans , Pregnenolone/metabolism , Progesterone/metabolism , Testosterone/metabolism
8.
J Chromatogr ; 111(1): 159-64, 1975 Aug 20.
Article in English | MEDLINE | ID: mdl-1158997

ABSTRACT

The behavior of 23 steroid oestrogens Sephadex LH-20 using six solvent systems was investigated. The fractions eluted by gel column chromatography were analysed by thin-layer chromatography and spectrometry. The method was used for the radiochemical purity of labelled compounds by isotopic dilution.


Subject(s)
Chromatography, Gel , Estrogens/analysis , Chromatography, Thin Layer , Estradiol/analogs & derivatives , Estradiol/analysis , Estrone/analogs & derivatives , Estrone/analysis , Indicators and Reagents , Spectrophotometry
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