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1Latest Papers from Table of Contents or Articles in PressE. Altindis ; M. A. Alpar ; E. Aksay ; J. Beckwith ; C. Bokel ; R. F. Curl ; R. B. Darnell ; S. J. Elledge ; B. Erman ; J. Frahm ; S. P. Goff ; P. Greengard ; R. Hoffmann ; B. Ilhan ; J. Kaslin ; S. M. Lipkin ; C. Poulopoulou ; E. Raz ; M. A. Rubin ; M. Salturk ; R. R. Schrock ; A. Trautmann ; D. Unutmaz ; H. Weinstein ; C. Kizil
American Association for the Advancement of Science (AAAS)
Published 2013Staff ViewPublication Date: 2013-07-23Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsKeywords: Asphyxia/*chemically induced/mortality ; Hospitalization/statistics & numerical data ; *Human Rights ; Humans ; Tear Gases/*toxicity ; Turkey ; Violence/*prevention & control ; Wounds and Injuries/etiology/mortalityPublished by: -
2Latest Papers from Table of Contents or Articles in PressM. G. Aartsen ; R. Abbasi ; Y. Abdou ; M. Ackermann ; J. Adams ; J. A. Aguilar ; M. Ahlers ; D. Altmann ; J. Auffenberg ; X. Bai ; M. Baker ; S. W. Barwick ; V. Baum ; R. Bay ; J. J. Beatty ; S. Bechet ; J. Becker Tjus ; K. H. Becker ; M. L. Benabderrahmane ; S. BenZvi ; P. Berghaus ; D. Berley ; E. Bernardini ; A. Bernhard ; D. Bertrand ; D. Z. Besson ; G. Binder ; D. Bindig ; M. Bissok ; E. Blaufuss ; J. Blumenthal ; D. J. Boersma ; S. Bohaichuk ; C. Bohm ; D. Bose ; S. Boser ; O. Botner ; L. Brayeur ; H. P. Bretz ; A. M. Brown ; R. Bruijn ; J. Brunner ; M. Carson ; J. Casey ; M. Casier ; D. Chirkin ; A. Christov ; B. Christy ; K. Clark ; F. Clevermann ; S. Coenders ; S. Cohen ; D. F. Cowen ; A. H. Cruz Silva ; M. Danninger ; J. Daughhetee ; J. C. Davis ; M. Day ; C. De Clercq ; S. De Ridder ; P. Desiati ; K. D. de Vries ; M. de With ; T. DeYoung ; J. C. Diaz-Velez ; M. Dunkman ; R. Eagan ; B. Eberhardt ; B. Eichmann ; J. Eisch ; R. W. Ellsworth ; S. Euler ; P. A. Evenson ; O. Fadiran ; A. R. Fazely ; A. Fedynitch ; J. Feintzeig ; T. Feusels ; K. Filimonov ; C. Finley ; T. Fischer-Wasels ; S. Flis ; A. Franckowiak ; K. Frantzen ; T. Fuchs ; T. K. Gaisser ; J. Gallagher ; L. Gerhardt ; L. Gladstone ; T. Glusenkamp ; A. Goldschmidt ; G. Golup ; J. G. Gonzalez ; J. A. Goodman ; D. Gora ; D. T. Grandmont ; D. Grant ; A. Gross ; C. Ha ; A. Haj Ismail ; P. Hallen ; A. Hallgren ; F. Halzen ; K. Hanson ; D. Heereman ; D. Heinen ; K. Helbing ; R. Hellauer ; S. Hickford ; G. C. Hill ; K. D. Hoffman ; R. Hoffmann ; A. Homeier ; K. Hoshina ; W. Huelsnitz ; P. O. Hulth ; K. Hultqvist ; S. Hussain ; A. Ishihara ; E. Jacobi ; J. Jacobsen ; K. Jagielski ; G. S. Japaridze ; K. Jero ; O. Jlelati ; B. Kaminsky ; A. Kappes ; T. Karg ; A. Karle ; J. L. Kelley ; J. Kiryluk ; J. Klas ; S. R. Klein ; J. H. Kohne ; G. Kohnen ; H. Kolanoski ; L. Kopke ; C. Kopper ; S. Kopper ; D. J. Koskinen ; M. Kowalski ; M. Krasberg ; K. Krings ; G. Kroll ; J. Kunnen ; N. Kurahashi ; T. Kuwabara ; M. Labare ; H. Landsman ; M. J. Larson ; M. Lesiak-Bzdak ; M. Leuermann ; J. Leute ; J. Lunemann ; J. Madsen ; G. Maggi ; R. Maruyama ; K. Mase ; H. S. Matis ; F. McNally ; K. Meagher ; M. Merck ; T. Meures ; S. Miarecki ; E. Middell ; N. Milke ; J. Miller ; L. Mohrmann ; T. Montaruli ; R. Morse ; R. Nahnhauer ; U. Naumann ; H. Niederhausen ; S. C. Nowicki ; D. R. Nygren ; A. Obertacke ; S. Odrowski ; A. Olivas ; A. O'Murchadha ; L. Paul ; J. A. Pepper ; C. Perez de los Heros ; C. Pfendner ; D. Pieloth ; E. Pinat ; J. Posselt ; P. B. Price ; G. T. Przybylski ; L. Radel ; M. Rameez ; K. Rawlins ; P. Redl ; R. Reimann ; E. Resconi ; W. Rhode ; M. Ribordy ; M. Richman ; B. Riedel ; J. P. Rodrigues ; C. Rott ; T. Ruhe ; B. Ruzybayev ; D. Ryckbosch ; S. M. Saba ; T. Salameh ; H. G. Sander ; M. Santander ; S. Sarkar ; K. Schatto ; F. Scheriau ; T. Schmidt ; M. Schmitz ; S. Schoenen ; S. Schoneberg ; A. Schonwald ; A. Schukraft ; L. Schulte ; O. Schulz ; D. Seckel ; Y. Sestayo ; S. Seunarine ; R. Shanidze ; C. Sheremata ; M. W. Smith ; D. Soldin ; G. M. Spiczak ; C. Spiering ; M. Stamatikos ; T. Stanev ; A. Stasik ; T. Stezelberger ; R. G. Stokstad ; A. Stossl ; E. A. Strahler ; R. Strom ; G. W. Sullivan ; H. Taavola ; I. Taboada ; A. Tamburro ; A. Tepe ; S. Ter-Antonyan ; G. Tesic ; S. Tilav ; P. A. Toale ; S. Toscano ; E. Unger ; M. Usner ; N. van Eijndhoven ; A. Van Overloop ; J. van Santen ; M. Vehring ; M. Voge ; M. Vraeghe ; C. Walck ; T. Waldenmaier ; M. Wallraff ; C. Weaver ; M. Wellons ; C. Wendt ; S. Westerhoff ; N. Whitehorn ; K. Wiebe ; C. H. Wiebusch ; D. R. Williams ; H. Wissing ; M. Wolf ; T. R. Wood ; K. Woschnagg ; D. L. Xu ; X. W. Xu ; J. P. Yanez ; G. Yodh ; S. Yoshida ; P. Zarzhitsky ; J. Ziemann ; S. Zierke ; M. Zoll
American Association for the Advancement of Science (AAAS)
Published 2013Staff ViewPublication Date: 2013-11-23Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsPublished by: -
3Latest Papers from Table of Contents or Articles in PressTrevor V. Gale, Timothy M. Horton, Andrew R. Hoffmann, Luis M. Branco, Robert F. Garry
American Chemical Society (ACS)
Published 2018Staff ViewPublication Date: 2018-11-06Publisher: American Chemical Society (ACS)Print ISSN: 1535-3893Electronic ISSN: 1535-3907Topics: Chemistry and PharmacologyPublished by: -
4Latest Papers from Table of Contents or Articles in PressK. K. Lange ; E. I. Tellgren ; M. R. Hoffmann ; T. Helgaker
American Association for the Advancement of Science (AAAS)
Published 2012Staff ViewPublication Date: 2012-07-24Publisher: American Association for the Advancement of Science (AAAS)Print ISSN: 0036-8075Electronic ISSN: 1095-9203Topics: BiologyChemistry and PharmacologyComputer ScienceMedicineNatural Sciences in GeneralPhysicsPublished by: -
5FIS Bildung LiteraturdatenbankStaff View
Type of Medium: articlePublication Date: 1993Keywords: Denken ; Schuljahr 07 ; Computer ; Computerunterstützter Unterricht ; Programm ; Unterrichtsmaterial ; Baumdiagramm ; Algorithmus ; Strukturiertes Programmieren ; Funktion (Math) ; Mathematik ; Mathematikunterricht ; Mathematisches Modell ; Diagramm ; Grafische DarstellungIn: Der Mathematikunterricht, Bd. 39 (1993) H. 3, S. 44-57, 0025-5807Language: GermanNote: Literaturangaben -
6Latest Papers from Table of Contents or Articles in PressStaff View
Publication Date: 2018-03-07Publisher: Institute of Physics Publishing (IOP)Electronic ISSN: 1748-0221Topics: PhysicsPublished by: -
7Latest Papers from Table of Contents or Articles in PressCheung, A., Opzoomer, J., Ilieva, K. M., Gazinska, P., Hoffmann, R. M., Mirza, H., Marlow, R., Francesch-Domenech, E., Fittall, M., Dominguez Rodriguez, D., Clifford, A., Badder, L., Patel, N., Mele, S., Pellizzari, G., Bax, H. J., Crescioli, S., Petranyi, G., Larcombe-Young, D., Josephs, D. H., Canevari, S., Figini, M., Pinder, S., Nestle, F. O., Gillett, C., Spicer, J. F., Grigoriadis, A., Tutt, A. N. J., Karagiannis, S. N.
The American Association for Cancer Research (AACR)
Published 2018Staff ViewPublication Date: 2018-10-16Publisher: The American Association for Cancer Research (AACR)Print ISSN: 1078-0432Electronic ISSN: 1557-3265Topics: MedicinePublished by: -
8Articles: DFG German National LicensesSUPAMATTAYA, K. ; FISCHER-SCHERL, T. ; HOFFMANN, R. W. ; BOONYARATPALIN, S.
Oxford, UK : Blackwell Publishing Ltd
Published 1991Staff ViewISSN: 1550-7408Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: BiologyNotes: Sphaerospora epinepheli n. sp. is described from grouper, Epinephelus malabaricus, in cage-cultured and wild fish collected from both coastal lines of southern Thailand. Subspherical to spherical spores and mono- or disporous pseudoplasmodia were observed in the lumen of kidney tubules. Pseudoplasmodia were round to elongate, size range 15.6–22.9 μm (length) × 8.4–21.6 μm (width). Spores were 7.8–10.0 μm (length) × 12.3–14.5 μm (thickness), and 7.0–9.5 μm (width) with two spherical polar capsules of equal size measuring 2.9–4.4 μm in diameter and containing polar filaments with six or seven windings. Two uninucleate sporoplasms showed iodine vacuoles. Blood stages, similar to C-blood protozoans observed from freshwater fish in Europe, were found from peripheral blood smears of grouper. Ultrastructural studies of blood stages showed a similar structure to unidentified mobile protozoans from the blood of carp. Electron dense bodies were observed in the cytoplasm of the primary cell blood stages. Infected proximal-tubular epithelial cells showed highly vacuolated cytoplasm and pycnotic nuclei.Type of Medium: Electronic ResourceURL: -
9Articles: DFG German National LicensesLöffler, H. ; Hoffmann, R. ; Happle, R. ; Effendy, I.
Oxford, UK : Blackwell Science Ltd
Published 2001Staff ViewISSN: 1365-2230Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: The standard method for evaluating contact allergy in mice is the ear swelling technique. However, in experimental irritant contact dermatitis, the epidermal barrier disruption, that represents a predominant effect of irritants, cannot be assayed by this method. An appropriate method to evaluate barrier disruption is the measurement of transepidermal water loss (TEWL) but to date this has so far been possible only on the trunk of hairless or shaved mice. We therefore developed a new technique to measure the TEWL of mice ears (murine auricular TEWL: MATEWL). After patch testing with irritants and allergens, respectively, we found that the ear swelling method is most suitable for evaluating allergic skin reactions, whereas MATEWL is most appropriate for evaluating irritant skin reactions.Type of Medium: Electronic ResourceURL: -
10Articles: DFG German National LicensesSamson, Y. ; Marty, A. ; Hoffmann, R. ; Gehanno, V.
[S.l.] : American Institute of Physics (AIP)
Published 1999Staff ViewISSN: 1089-7550Source: AIP Digital ArchiveTopics: PhysicsNotes: Thin films of tetragonal ordered alloys grown by molecular beam epitaxy provide a unique template for the study of magnetic configurations in thin films with perpendicular anisotropy. These configurations have been investigated by magnetic force microscopy over a wide thickness range, for large and weak perpendicular anisotropies, in both equilibrium and out of equilibrium states. FePd samples ordered into the tetragonal L10 structure have been obtained by simultaneous evaporation of Fe and Pd on Pd(100). These samples exhibit large perpendicular anisotropy. Magnetic domains have been imaged as a function of increasing thickness from 1.4 to 100 nm. Both an exponential decrease of the domain size at low thickness and a slow increase at higher thickness have been observed, allowing quantitative confirmation of the theoretical evolution expected. Due to this exponential decrease of their equilibrium size, the domains appearing at the beginning of growth exhibit a large size, well above the equilibrium one when the layer thickness is thereafter increased. The growth of the layer then leads to highly out of equilibrium magnetic configurations, where the domain shape evolves through wall undulation at low thickness and thereafter through a fingering instability. This fingering instability preserves large parts of the initial domains, allowing a quantitative estimation of the strain to which they are submitted. Samples grown with a low chemical order exhibit weak perpendicular anisotropy. The magnetization then lies into the plane below a critical thickness. Above this thickness, the images confirm the square root dependence of the period of the stripe structure upon thickness. Stripes as small as 37 nm have been observed. © 1999 American Institute of Physics.Type of Medium: Electronic ResourceURL: -
11Articles: DFG German National LicensesStaff View
ISSN: 1750-3841Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, NutritionProcess Engineering, Biotechnology, Nutrition TechnologyNotes: Volatile samples for gas chromatographic analysis can he collected and enriched by slow passage through a gas-syringe barrel packed with solvent-dampened cotton. Then the condensate can be injected into a gas chromatograph directly from the same syringe.Type of Medium: Electronic ResourceURL: -
12Articles: DFG German National LicensesStaff View
ISSN: 1095-8649Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: BiologyNotes: Penetration of triactinomyxon–sporoplasms of Myxobolus cerebralis through skin, fins, gills and buccal cavity have been demonstrated experimentally in rainbow trout. Furthermore the multiplication–stages of penetrated triactinomyxon–sporoplasms reach the cartilage via peripheral nerves and the central nervous system (CNS). This is in contrast to the assumption that the agent reaches the cartilage via blood, lymph, and/or coelomic fluid. During the first hour following penetration, the sporoplasm migrates between the epidermal cells. Then, it enters the epithelia and multiplies intracellularly. These stages migrate deeper into the subcutis, then through the peripheral nerves and CNS. After about 21 days the parasites reach the head cartilages. During their migration they also multiply to increase parasite numbers. The ultrastructure of the proliferative phase (presporogonic development) and the sporogonic phase of the life cycle are demonstrated and discussed.Type of Medium: Electronic ResourceURL: -
13Articles: DFG German National LicensesMcElwee, K. J. ; Niiyama, S. ; Freyschmidt-Paul, P. ; Wenzel, E. ; Kissling, S. ; Sundberg, J. P. ; Hoffmann, R.
Oxford, UK : Munksgaard International Publishers
Published 2003Staff ViewISSN: 1600-0625Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Abstract: Alopecia areata (AA) is a complex, multi-factorial disease where genes and the environment may affect susceptibility and severity. Diet is an environmental factor with the potential to influence disease susceptibility. We considered dietary soy (soya) oil content and the soy-derived phytoestrogen genistein as potential modifying agents for C3H/HeJ mouse AA. Normal haired C3H/HeJ mice were grafted with skin from spontaneous AA affected mice, a method previously shown to induce AA. Grafted mice were given one of three diets containing 1%, 5% or 20% soy oil and observed for AA development. In a separate study, mice on a 1% soy oil diet were injected with 1 mg of genistein three times per week for 10 weeks or received the vehicle as a control. Of mice on 1%, 5%, and 20% soy oil diets, 43 of 50 mice (86%), 11 of 28 mice (39%), and 2 of 11 mice (18%) developed AA, respectively. Four of 10 mice injected with genistein and 9 of 10 controls developed AA. Mice with AA had hair follicle inflammation consistent with observations for spontaneous mouse AA, but no significant association was observed between the extent of hair loss and diet or genistein injection. Mice that failed to develop AA typically regrew white hair from their skin grafts associated with a moderate macrophage and dendritic cell infiltration. Soy oil and derivatives have previously been reported to modify inflammatory conditions. Hypothetically, soy oil compounds may act on C3H/HeJ mice through modulating estrogen-dependent mechanisms and/or inflammatory activity to modify AA susceptibility.Type of Medium: Electronic ResourceURL: -
14Articles: DFG German National LicensesNiiyama, S. ; Happle, R. ; Hoffmann, R.
Copenhagen : Munksgaard International Publishers
Published 2001Staff ViewISSN: 1600-0625Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Abstract: Androgenetic alopecia (AGA) is a dihydrotestosterone-mediated process, characterized by continuous miniaturization of androgen sensitive hair follicles (HF). Although increased 5α-reductase (5aR) activity in affected HF is a key feature in the pathogenesis of AGA, only little is known about the in vivo expression of 5aR within AGA-affected HF. Recent studies have shown that the dermal papilla (DP) is the predominant site of type 2 5aR expression within the human HF, but direct measurements of 5aR activity in intact DP of AGA-affected HF have not been reported so far, mainly because of technical problems. Hence there is a need for a reliable and sensitive method of measuring 5aR activity in fresh tissues. As a novel approach, we used freshly isolated, intact DP and a highly sensitive HPLC-radiomatic flow scintillation system to measure 5aR. In this way we were able to measure 5aR even in small DPs from miniaturized HF. Our results show that DP from the occipital scalp express ex vivo considerable amounts of 5aR activity, but the measurable enzyme activities of individual DP differ considerably. Therefore the use of only one or two DP is at present not a reliable tool to analyze 5aR activity ex vivo.Type of Medium: Electronic ResourceURL: -
15Articles: DFG German National LicensesTUFARIELLO, J. A. M. ; HOFFMANN, R. ; BISSON, M. A.
Oxford, UK : Blackwell Publishing Ltd
Published 1988Staff ViewISSN: 1365-3040Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: BiologyNotes: Abstract The freshwater Charophyte Chora corallina dies when subjected to 70 molm−3 NaCl if the Ca2+ concentration is 0.1 mol m −3. This stress is accompanied by a depolarization of the cell to a membrane potential more positive than EK, a net influx of Na+ into the vacuole, and a net loss of K+ from the vacuole. Raising the Ca2+ concentration to 7 mol m −3 in the presence of elevated Na+ restores the Na+ to Ca2+ ratio to 10: 1 as in the control solution, and results in enhanced survival even though turgor is not regulated. Mg2+ is not a good substitute for Ca2+. It is suggested that the main reason that C. corallina fails to occupy saline habitats is its failure to regulate turgor, not sensitivity to Na +, since the latter is similar to that seen in C. buckellii, which is found in saline habitats.Type of Medium: Electronic ResourceURL: -
16Articles: DFG German National LicensesStaff View
ISSN: 1365-3040Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: BiologyNotes: Abstract The comparative Na+ tolerance of Chora buckellii cultured in freshwater (FW) or artificial Waldsea water (AWW, which contains about 110 mol m−3 each Na +, Mg2+, Cl− and SO2-4 was tested with respect to the external Na+ to Ca2+ ratio (Na: Ca). Fifty per cent of FW cells subjected to 70 mol m−3 NaCl, which raised Na:Ca from 10: 1 to 700: 1 and the external osmotic pressure from 0.024 to 0.402 MPa, died within 6 d. Death was associated with the loss of Na/K selectivity, H+ -pump activity and turgor. Restoration of Na:Ca to 10:1 in high Na+ medium with CaCl2 ensured 100% survival and maintained H+-pump activity and Na/K selectivity of FW cells. Turgor was regulated within 3 d with net uptake of Na +, K+ and Cl− in the vacuolc. Mg2+ was not as effective as Ca2+ in enhancing survival or maintaining H+ -pump activity and Na/K selectivity of FW cells in the presence of elevated Na+. However, turgor was regulated within 3 d by accumulation of Cl− and an unknown cation in the vacuole. All AWW cells subjected to an increase of 70 mol m −3 NaCl, which raised Na: Ca from 16:1 to 25: 1 and the external osmotic pressure from 0.915 to 1.22 MPa, survived and maintained H + -pump activity. Turgor was regulated within 6d by accumulating Na +, K+ and Cl− in the vacuole. All AWW cells subjected to 70molm−3 NaCl in a medium in which Na:Ca was equal to 700:1 survived and maintained H + -pump activity, but showed loss of Na/K selectivity. Turgor was regulated with an unknown osmoticum(a) within 6 d.Type of Medium: Electronic ResourceURL: -
17Articles: DFG German National LicensesStaff View
ISSN: 1365-2230Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Summary Several rodent models with spontaneous and induced alopecia areata (AA), a nonscarring inflammatory hair loss disease with suspected autoimmune elements, have been identified. Of these, the C3H/HeJ mouse and DEBR rat have been most extensively used in examining AA development. Flow cytometry and micro array characterization, manipulation of inflammatory cells by in vivo cell depletion or cell receptor blockade, lymph node cell transfer between affected and unaffected rodents, and the recent use of transgenic knockout mice have given important insights into the development of AA. From our current understanding of rodent models, the development of AA relies upon a general genetic susceptibility where major susceptibility genes may be supplemented by minor disease severity modifying genes. However, the actual onset of AA, its duration, extent, and persistence in individual rodents may be modified by epigenetic factors. Rodent AA seems to be fundamentally, but not exclusively, Th1 cell mediated. Onset of disease may be dependent on several factors including the break down of the putative anagen stage hair follicle immune privilege, appropriate antigen presentation with costimulation of lymphocytes, presence of autoreactive lymphocytes, and a deficiency of functional immune system regulatory cells. Rodents have already been used in examining a variety of current AA treatments and developing new therapies with some success. With a greater understanding of AA disease mechanisms through rodent model research, improved and more specific treatment interventions may be defined.Type of Medium: Electronic ResourceURL: -
18Articles: DFG German National LicensesStaff View
ISSN: 1365-2230Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Summary Androgenetic alopecia (AGA) is the most common type of hair loss in men. The relative strong concordance of the degree of baldness in fathers and sons is not consistent with a smiple Mendelian trait and a polygenic basis is considered to be most likely. So far the predisposing genes for AGA are unknown and we do not understand the molecular steps involved in androgen-dependent beard growth versus androgen-dependent hair loss, but AGA can be defined as a DHT-dependent process with continuous miniaturization of sensitive hair follicles. The type 2 5aR plays a central role by the intrafollicular conversion of T to DHT. Due to the inceasing knowledge in this field, this article shall privide an critical overwiew of recent discoveries.Type of Medium: Electronic ResourceURL: -
19Articles: DFG German National LicensesEICHELER, W. ; DREHER, M. ; HOFFMANN, R. ; HAPPLE, R. ; AUMÜLLER, G.
Oxford, UK : Blackwell Publishing Ltd
Published 1995Staff ViewISSN: 1365-2133Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Antibodies raised against fragments of synthetic peptides of human 5α-reductase isoenzymes 1 (h5αrl) and 2 (h5αr2) were applied to paraffin sections of human skin (scalp, eyelid, lip, breast, scrotum).Immunoreactive sites were differentially distributed, in that h5αrl immunoreactivity was present in the nuclei of cells in the stratum germinativum (basal and lower portion of the spinous layer) of the epidermis, subepithelial tibroblasts, adipocytes, smooth muscle cells of the scrotal tunica dartos, basal cells of sebaceous glands, excretory duct cells of sweat glands, cells of the dermal papilla and fibrous and outer epithelial sheath of hair roots, as well as endothelial cells of small vessels and Schwann cells of cutaneous myelinated nerves. In contrast, immunoreactivity for h5αr2 was found in the cytoplasm of the cells of the spinous layer (and far less intensely in the basal layer) of the epidermis, subepidermal fibrocytes, and especially in subcutaneous adipocytes. Immunoreactivity was strongest in the non-keratinized portion of the inner epithelial sheath and the cuticle of hair follicles, whereas other portions of the hair root were negative. Sweat glands were stained, whereas sebaceous glands showed only weak diffuse immunoreactivily. In mucoculaneous zones, salivary glands and conjunctival epithelium showed immunoreactive cells. Vascular endothelium displayed immunoreactivity only in the genital region. We present experimental evidence for a differential distribution of 5α-reductase isoenzymes in human skin. This might reflect a diversity in the response of different areas of the skin to androgenic challenge.Type of Medium: Electronic ResourceURL: -
20Articles: DFG German National LicensesHoffmann, R. ; Niiyama, S. ; Huth, A. ; Kissling, S. ; Happle, R.
Oxford, UK : Munksgaard International Publishers
Published 2002Staff ViewISSN: 1600-0625Source: Blackwell Publishing Journal Backfiles 1879-2005Topics: MedicineNotes: Abstract: For topical treatment of androgenetic alopecia (AGA) in women, solutions containing either estradiol benzoate, estradiol valerate, 17β- or 17α-estradiol are commercially available in Europe and some studies show an increased anagen and decreased telogen rate after treatment as compared with placebo. At present it is not precisely known how estrogens mediate their beneficial effect on AGA-affected hair follicles. We have shown recently that 17α-estradiol is able to diminish the amount of dihydrotestosterone (DHT) formed by human hair follicles after incubation with testosterone, while increasing the concentration of weaker steroids such as estrogens. Because aromatase is involved in the conversion of testosterone to estrogens and because there is some clinical evidence that aromatase activity may be involved in the pathogenesis of AGA, we addressed the question whether aromatase is expressed in human hair follicles and whether 17α-estradiol is able to modify the aromatase activity. Herewith we were able to demonstrate that intact, microdissected hair follicles from female donors express considerably more aromatase activity than hair follicles from male donors. Using immunohistochemistry, we detected the aromatase mainly in the epithelial parts of the hair follicle and not in the dermal papilla. Furthermore, we show that in comparison to the controls, we noticed in 17α-estradiol-incubated (1 nM) female hair follicles a concentration- and time-dependent increase of aromatase activity (at 24 h: 1 nM = +18%, 100 nM = +25%, 1 µM = +57%; 24 h: 1 nM = +18%, 48 h: 1 nM = +25%). In conclusion, our ex vivo experiments suggest that under the influence of 17α-estradiol an increased conversion of testosterone to 17β-estradiol and androstendione to estrone takes place, which might explain the beneficial effects of estrogen treatment of AGA.Type of Medium: Electronic ResourceURL: