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P Lehmann

Publications and source records attributed to P Lehmann.

At least 19 recordsLinked to original sources
PubMed2006

[Varying characteristics of subcutaneous and dermal leiomyosarcomas. Two case reports and literature review].

Cutaneous leiomyosarcomas (LMS) originating from smooth muscle of the skin are rare malignant neoplasms. Preferential sites are hair-bearing areas, especially the legs. We report two patients in their 5th and 7th decade, in whom leiomyosarcomas were encountered in the lower leg and the capillitium, respectively. Histologically, the former was found to be a dermal leiomyosarcoma with subcutaneous infiltration, the latter an exclusively dermal tumor. The LMS of the lower leg had been excised three years previously in a different institution and had been diagnosed as a leiomyoma. Both lesions were excised with adequate safety margins in our institution and within a two-year postoperative observation period no recurrences were encountered. Dermal leiomyosarcomas have a 33% recurrence rate while that of subcutaneous leiomyosarcomas show is 50%. In contrast to exclusively dermal tumors, subcutaneous LMS show a tendency for hematogenic and lymphogenic metastases. Therapy of choice is excision with wide safety margins.

Aged↗
PubMed2006

[MRI localization of paraclinoid carotid aneurysms].

AIM: The distal dural ring plane (DDRP) separates the intracavernous from the supracavernous paraclinoid internal carotid artery. The purpose of this MRI protocol is to evaluate the position of this plane for the characterization of paraclinoid aneurysms. METHOD: The protocol uses a T2 weighted sequence in two orthogonal planes (diaphragmatic and carotid planes) and two correlation lines in each plane. These lines pass through anatomo-radiological reference points correlated with the medio-lateral and antero-posterior margins of the DDRP. We use the intersection angle of these lines as the inferior radiological limit of the DDRP curve. RESULTS: An aneurysm located above this angle is supracavernous; an aneurysm located below this angle is intracavernous; an aneurysm crossing this angle is transitional. CONCLUSION: In difficult cases, this MRI protocol could help better characterize the exact localization of paraclinoid aneurysms on both sides of the cavernous sinus roof.

Carotid Artery Diseases↗
PubMed2005

Morphometric analysis of Triatoma dimidiata populations (Reduviidae:Triatominae) from Mexico and Northern Guatemala.

Triatoma dimidiata is one of the major vectors of Chagas disease in Latin America. Its range includes Mexico, all countries of Central America, Colombia, and Ecuador. In light of recent genetic analysis suggesting that the possible origin of this species is the Yucatan peninsula, we have analyzed populations from the state of Yucatan, San Luis Potosi, and Veracruz in Mexico, and a population from the southern region of the Yucatan peninsula located in Northern Guatemala, the region of El Peten. Classical morphometry including principal component, discriminant, sexual dimorphism, and wing asymmetry was analyzed. San Luis Potosi and Veracruz populations were indistinguishable while clearly separate from Yucatan and Peten populations. Despite important genetic differences, Yucatan and Peten populations were highly similar. Yucatan specimens were the smallest in size, while females were larger than males in all populations. Only head characters were necessary to distinguish population level differences, although wing fluctuating asymmetry was present in all populations. These results are discussed in light of recent findings suggesting genetic polymorphism in most populations of Triatoma dimidiata south of Chiapas to Ecuador.

Animals↗
PubMed2005

[Dapsone-induced agranulocytosis. The role of xenobiotic-metabolizing enzymes demonstrated by a case report].

A 34-year-old female patient with a three year history of generalized granuloma annulare was treated systemically with dapsone (DADPS). Six weeks after the onset of treatment, the patient developed an extensive tonsillitis of the base of the tongue with fever and malaise. Routine laboratory work showed a leukocytopenia with agranulocytosis. Further investigation revealed a marked decrease of the enzyme activity of N-acetyltransferase 2, which plays an important role in dapsone metabolism. Treatment included the cessation of dapsone, antibiotic coverage, and G-CSF leading to the rapid improvement of symptoms and normalization of leukocyte counts. Dapsone-induced angina agranulocytotica is a rare event and is interpreted as an idiosyncratic reaction. Depending on genetic polymorphisms of various enzymes, dapsone can be metabolized to immunologically or toxicologically relevant intermediates. Because of the risk of severe hematologic reactions, dapsone should only be employed for solid indications and with appropriate monitoring.

Adult↗
PubMed2005

[Rosacea. Clinical features, pathogenesis and therapy].

Rosacea is a common facial dermatosis, which may have detrimental effects on the patient's psychological and social interactions. It is a disease of the middle aged, skin types I and II are more often affected than darker skin types. Clinically, pre-rosacea, and rosacea grade I-III may be distinguished. Pre-rosacea is characterized by flushing and blushing, grade I to III by erythemato-teleangiectasies, papulopustules, and inflammatory nodules. Especially severe subtypes include rosacea conglobata and rosacea fulminans. Hyperglandular subtypes lead to different forms of phyma, of which Rhinophyma is the most frequent. Pathogenetically destruction of the dermal vessels and connective tissue seems to be decisive for the development of a chronic inflammation, which leads to the phenotype of the various forms of rosacea. Mild forms can be treated exclusively by topical medication. Antibiotics (erythromycin, clindamycin, tetracyclin), metronidazol, azelaic acid, and the retinoid adapalene have been shown to be effective in well controlled randomized studies. The best evaluated topical medication is metronidazol. In severe forms systemic therapy must be applied. Systemic antibiotics are effective and especially isotretinoin has shown a very good response even in low dose regimens. Rhinophyma must be treated surgically.

Anti-Bacterial Agents↗
PubMed2005

[Intra cranial abscess and empyemas from E.N.T. origin].

OBJECTIVES: The purpose of this study was to evaluate the diagnosis criteria, the bacteriology and the evolution after adapted treatment of intracranial abscess of ENT origin. MATERIAL AND METHODS: It was a retrospective study from 1985 to 2003 concerning 22 patients who had brain abscesses secondary to an ENT infection. RESULTS: The infectious origin was sinusoid in 32% of cases, otologic in 32% of cases, pharyngeal or dental in 27% of cases and cutaneous in 9% of cases. The clinical symptoms were: fever in 55% of cases, headache in 73% of cases (Intra cranial hypertension syndrome in 23% of cases), epilepsy in 32% of cases and various other neurologic symptoms. Bacteria were identified in 82% of cases. In 50% of cases multibacterial associations were found. All the patients had bi antibiotherapy associated to surgical excision of the abscess (16 cases) or single (or more) punction (stereotaxic guided or not) of the abscess. 3 patients (14%) died and 50% are alive and well. CONCLUSION: The diagnosis of cerebral abscess is often difficult. The "classical" intracranial hypertension associated to high fever is usually incomplete and sometimes absent. There is no predominant bacteria involved and multibacterial infections are frequent. Despite abscesses are serious and potentially lethal, an early diagnosis, a medical (antibiotics) and surgical treatment (punction and/or surgical excision) may completely be cured in more than 50% of cases.

Adolescent↗
PubMed2004

Photopatch testing: a consensus methodology for Europe.

A group of interested European Contact Dermatologists/Photobiologists met to produce a consensus statement on methodology, test materials and interpretation of photopatch testing. While it is recognized that a range of local variables operate throughout Europe, the underlying purpose of the work is to act as an essential preamble to a Pan European Photopatch Test Study focusing particularly on sunscreen chemicals.

Dermatitis, Photoallergic↗
PubMed2003

[Photodermatoses during childhood].

Actinic dermatitis and phototoxic and idiopathic photodermatoses occur relatively often during childhood. Photodermatoses stemming from enzyme defects and genetic disorders are much less common, while photoallergic and chronic actinic dermatitis have not been dealt with to date. A specific sensitivity of a child's skin to light is often the first manifest clinical symptom of a photodermatosis, the key is to ensure early diagnosis. However, it is often difficult to reach a diagnosis, as the lesions are barely perceptible or have even healed by the time the patient is examined. This is why photoprovocation tests are so important in diagnosing photodermatoses, particularly during childhood. In addition to early diagnosis of these illnesses and offering the appropriate treatment, it is also crucial that the parents be well informed and aware of what symptoms to look for so that they can protect their children from overexposure to UV light and thereby avoid later actinic injuries that can become as serious as malignancies.

Adolescent↗
PubMed2003

The photopatch test procedure of the German, Austrian, and Swiss photopatch test group.

In 1984 the German, Austrian, and Swiss photopatch test group was established to investigate photoallergic reactions as well as the epidemiology of photoallergy in central Europe. Therefore, the photopatch test procedure was defined and photopatch test data of 3998 patients were evaluated after two test periods from 1984 to 1990 and from 1991 to 1997. In summary, non-steroidal anti-inflammatory drugs, disinfectants, phenothiazines as well as sunscreens were found to be relevant photoallergens in central Europe. Based on the study results and guided by contemporaneously published clinical findings, the German, Austrian, and Swiss photopatch test group released in the year 2000 an optimized photopatch test tray, including a block of 19 photosensitizers, ranging from some historical to newly reported photosensitizers. This standard set is complemented by an optional photopatch test set, indicated only in special cases.

Allergens↗
PubMed2003

[Lenticulostriate aneurysms. Radioclinical study].

The authors report four cases of aneurysm of the lenticulostriate arteries, three idiopathic and one with underlying MoyaMoya disease. This unusual pathology, which often affects young patients, is revealed by a meningeal syndrome and sometimes focal neurological signs. The bleeding is highlighted by a CT scan without contrast injection, even by MRI, these examinations making it possible to evaluate its repercussion. Arteriography or MRA show the aneurysm and eliminate vascular malformation. According to literature (15 cases published) and our experience, considering the difficulty of a surgical or endovascular approach, morbidity and the frequency of spontaneous thromboses, it seems that a conservative management is justified after a negative etiologic check-up and under radio-clinical monitoring.

Adult↗
PubMed2002

Temperature- and time-resolved X-ray scattering at thin organic films.

Multilayers of an Fe(II)-polyelectrolyte-amphiphile complex (Fe-PAC) were investigated simultaneously by energy-dispersive X-ray reflectivity and in-plane diffraction at the bending-magnet beamline at BESSY II. By recording spectra between room temperature and about 348 K with a time resolution of about 60 s, two phase transitions were identified and the respective activation energies were determined. Owing to a fixed geometrical set-up, an energy-dispersive experiment is suitable for measuring X-ray reflectivity and in-plane X-ray diffraction of thin organic films simultaneously. Installed at a bending magnet at BESSY II and using an energy range of 4 < E < 25 keV, both reflectivity and diffraction spectra can be collected within about 60 s. The performance is demonstrated by temperature- and time-resolved measurements of the phase transition behaviour of multilayers of an Fe-PAC deposited on a silicon support by means of the Langmuir-Blodgett (LB) technique. By measuring the X-ray reflectivity while increasing the temperature, it is shown that the original LB phase is not stable and transforms irreversibly into a liquid-crystalline (LC)-like phase at about 318 K. At the same temperature the in-plane diffraction signal vanishes reversibly, reflecting rotational disorder of the hexagonal arrangement of amphiphilic chains. Its activation energy is determined to be about 1.3 eV. At about 338 K a second irreversible phase transition occurs to another LC phase with smaller vertical layer spacing. This transition is reversible between 329 K and 338 K.

Journal Article↗
PubMed2002

Upregulation of epidermal surface molecule expression in primary and ultraviolet-induced lesions of lupus erythematosus tumidus.

BACKGROUND: Lupus erythematosus tumidus (LET), a photosensitive skin disorder with characteristic clinical and histological features, has not been generally accepted as a subset of cutaneous lupus erythematosus (CLE). OBJECTIVES: To analyse the expression of epidermal surface molecules in skin biopsy specimens from patients with LET and to relate the results to other variants of CLE, such as discoid lupus erythematosus (DLE) and subacute CLE (SCLE). METHODS: In total, 45 patients with different subtypes of CLE were included in the study, and cryostat sections from primary and ultraviolet (UV) A- and UVB-induced skin lesions were investigated using immunohistochemical methods. RESULTS: In contrast to healthy controls, skin lesions of LET showed upregulation of intercellular adhesion molecule-1 (ICAM-1) and histocompatibility class II molecules (HLA-DR), with an expression pattern resembling that seen in DLE and SCLE. Furthermore, staining with a monoclonal antibody against 27E10, a distinct marker for cell activation and differentiation, revealed intense focal or band-like labelling of all epidermal layers independent of the type of lesion. CONCLUSIONS: Expression of epidermal surface molecules such as ICAM-1, HLA-DR and 27E10 is equally upregulated in primary and UV-induced lesions of patients with LET, DLE and SCLE. These results support our recent clinical findings that LET represents a distinct subset of CLE with a similar immunopathomechanism rather than a different disease.

Adult↗
PubMed2001

The 5-aminolevulinic acid-induced porphyrin biosynthesis in benign and malignant cells of the skin.

In fluorescence diagnosis and photodynamic therapy of neoplastic tissues 5-aminolevulinic acid is used to synthesize endogenous porphyrins as photosensitizers. The efficacy of neoplastic tissues to fluorescence diagnosis and photodynamic therapy is thought to be dependent on the total level of intralesional formed porphyrins. The available profiles of porphyrin metabolites in normal and in neoplastic cell lines after administration of 5-aminolevulinic acid vary considerably. Thus, this is the first in-vitro study which compares the porphyrin biosynthesis in normal skin cells (HaCaT, fibroblasts) with melanoma cells (Bro, SKMel-23, SKMel-28). After incubation with 1 mM 5-aminolevulinic acid, kinetics of porphyrin levels and metabolites were determined in the cells and the corresponding supernatants. Exogenous 5-aminolevulinic acid induced porphyrin formation in all cells with maximum values after an incubation period of 16-36 h. Increase of porphyrin levels varied from 10- to 80-fold (SKMel-28>HaCaT>fibroblasts>SKMel-23>>Bro) with minimum 1.5 times higher levels of porphyrins in the supernatants than in the cells. In cells and supernatants protoporphyrin and coproporphyrin were the predominantly formed porphyrin metabolites. Metastatic melanoma cells (SKMel-23, SKMel-28) accumulated much higher porphyrin levels than primary melanoma cells (Bro). In conclusion, by optimizing the treatment modalities, especially the light source, topical photodynamic therapy (PDT) could become a treatment alternative of melanoma metastases in progressive disease.

Aminolevulinic Acid↗
PubMed2001

Structural analysis of a metallosupramolecular polyelectrolyte-amphiphile complex at the air/water interface.

A detailed analysis of a metallosupramolecular coordination polyelectrolyte-amphiphile complex (PAC) at the air/water interface is presented based on Langmuir isotherm measurements, Brewster angle microscopy as well as X-ray reflectance and diffraction measurements. The PAC is prepared in solution by metal-ion coordination of Fe(OAc)2 and 1,4-bis(2,2':6',2"-terpyridin-4'-yl)benzene followed by self-assembly with dihexadecyl phosphate (DHP). The spreading of the PAC at the air/water interface results in a Langmuir film with a stratified architecture, such that DHP forms a monolayer on the water surface, while the metallosupramolecular coordination polyelectrolyte (MEPE) is immersed in the aqueous subphase. Electrostatic interactions of MEPE and DHP force the alkyl chains into an upright, hexagonal lattice even at low surface pressures. This work illustrates how supramolecular, colloidal, and surface chemistry can be combined to create complex architectures with tailored characteristics that may not be accessible through self-organization in the liquid phase.

Journal Article↗
PubMed2001

[Rediscovery of thalidomide. Successful treatment of discoid lupus erythematosus].

Thalidomide, an oral drug introduced in Germany in 1953 as a mild sedative, was withdrawn from the world market when its teratogenic effect was discovered some years later. It has since been selectively reintroduced to treat a variety of autoimmune or inflammatory diseases such as erythema nodosum leprosum, prurigo nodularis, graft-versus-host disease, and discoid lupus erythematosus (DLE). We report on three patients with long-standing, severe DLE showing no response to systemic first-, second- and third-line treatments. After four weeks of therapy with thalidomide the skin lesions had improved dramatically and after three to six months all three patients responded with an almost complete remission. The side effects of thalidomide, especially somnolence and paresthesias, were minor and well tolerated by the patients. Our data confirm that thalidomide provides one of the most useful therapeutic alternatives for chronic refractory DLE, despite the risks of teratogenicity and polyneuropathy.

Adult↗