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F Eckert

Publications and source records attributed to F Eckert.

At least 19 recordsLinked to original sources
PubMed2001

COSMO-RS: a novel view to physiological solvation and partition questions.

Both, dielectric continuum solvation models as well as surface or group based methods using polarity and lipophilicity parameters have been proven to be useful tools for the analysis of solvation and partition questions. For the first time, COSMO-RS provides an integrated theory, which combines the aspects of continuum solvation and surface interactions, and which ends up with chemical potentials of molecules in almost arbitrary solvents and mixtures. Due to its sound theoretical basis, COSMO-RS does not only provide a new quantitative access to solvation and partition properties in well defined solvents, but it also opens a novel view and gives a better understanding of the general problem of solvation. Finally, this allows for a generalisation of COSMO-RS to sophisticated physiological partition problems involving as complex phases as blood, brain, or cell membranes. The use of COSMO-RS for drug discovery and design is demonstrated by applications to blood-brain partition coefficients, and water solubility.

Blood-Brain Barrier↗
PubMed1997

Palpable migratory arciform erythema. Clinical morphology, histopathology, immunohistochemistry, and response to treatment.

BACKGROUND: Palpable migratory arciform erythema is clinically characterized by sharply circumscribed, infiltrated erythematous patches that tend to spread irregularly, resulting in arciform morphologic features. The histopathologic features are characterized by a patchy inflammatory perivascular and periadnexal T-lymphocytic infiltrate throughout the dermis. The disease runs a chronic course and is rarely described in the literature. OBSERVATION: Three middle-aged patients of both sexes had palpable migratory arciform erythema with 1, several, or multiple lesions on the trunk. There was a dense perivascular and periadnexal, predominantly lymphocytic infiltrate of the reticular dermis without any interstitial distribution of inflammatory cells. Absence of mucin deposits and plasma cells was a striking feature. The immunohistochemical profile showed an infiltrate dominated by T cells of polyclonal origin. In addition, polyclonal B cells and histiocytes were present in small numbers. In all 3 cases, oral antibacterial treatment resulted in a complete (2 patients) or temporary (1 patient) resolution of skin lesions. CONCLUSIONS: Palpable migratory arciform erythema shows distinctive differences in clinical and pathological features and treatment in contrast to other diseases with cutaneous lymphocytic infiltrates, including lymphocytic infiltration of Jessner and Kanof. Therefore, it is likely a distinct disease entity.

Adult↗
PubMed1997

Apocrine cystadenoma, apocrine hidrocystoma, and eccrine hidrocystoma: three distinct tumors defined by expression of keratins and human milk fat globulin 1.

Eccrine hidrocystomas and apocrine cystadenomas are morphologically related cystic sweat gland tumors. To elucidate their cellular differentiation we examined by immunohistochemistry the expression of keratins and of human milk fat globulin 1 in 12 of each of these tumors, diagnosed using established conventional histological criteria. All tumors diagnosed as apocrine cystadenomas by these criteria were characterized by a keratin pattern of secretory type. In addition, they expressed human milk fat globulin 1. Tumors diagnosed as eccrine hidrocystomas expressed a keratin pattern of excretory type. A part of the tumors with an excretory keratin pattern expressed human milk fat globulin, while others did not. Some presumed eccrine hidrocystomas expressed the very same antigens as apocrine cystadenomas. Thus, our study reveals three distinct types of tumors, in contrast to the conventional distinction of only eccrine hidrocystomas and apocrine cystadenomas. Apocrine cystadenomas differentiate towards the secretory coil of apocrine sweat glands. Presumed eccrine hidrocystomas may represent cystic tumors of the eccrine sweat duct, or they may represent cystic tumors of the apocrine duct. Thus, the name hidrocystoma should be used without further specification of an eccrine or apocrine nature, unless certainty is reached by immunohistochemical characterization. Also, hidrocystomas often prove to be histologically misdiagnosed apocrine cystadenomas because of a flattened cyst wall secondary to increased intraluminal pressure.

Apocrine Glands↗
PubMed1996

[Epithelioid cell histiocytoma].

We report on seven examples of this rare, only recently described benign tumor, which presented clinically as solitary elevated nodules on the lower (n = 5) and upper (n = 2) extremity, measuring between 0.6 and 1.1 cm in diameter. Histologically, all tumors were well-defined with a characteristic epidermal collarette. There were abundant (60-80%) epithelioid cells with prominent cytoplasm, a vesicular nucleus and inconspicuous nucleolus, as well as a number of dilated blood vessels. Immunohistologically, tumor cells did not react with monocyte/macrophage antibodies (KP1, MAC387). In addition, there was no evidence of myofibroblastic differentiation (alpha-smooth muscle actin and desmin negative). Thus, while immunohistological markers are helpful to exclude the diagnosis of other tumors, they do not shed light on the differentiation of epithelioid cell histiocytomas. The present cases are identical to those described originally. Recently similar lesions have been described in deeper parts of the corium as well as more cellular forms. Epithelioid cell histiocytoma represents a characteristic, poorly known variant within the spectrum of benign fibrous histiocytomas; it needs to be distinguished clinically and histopathologically especially from Spitz nevus.

Adult↗
PubMed1995

Cutaneous follicular lymphoid hyperplasia with monotypic plasma cells. A clinicopathologic study of 18 patients.

Twenty cases of cutaneous follicular lymphoid hyperplasia with monotypic plasma cells are presented in a clinicopathologic study on 18 patients. The plaque-like or nodular lesions were solitary in 10 and multiple in eight patients. Immunohistochemistry showed well-defined B- and T-cell areas. Sheets of monotypic plasma cells occurred either interfollicularly or adjacent to the sclerotic stroma, with expression of IgG/kappa in 14 and IgG/lambda in six cases. In one patient with multiple lesions, one sample contained polyclonal plasma cells, whereas the other specimen showed light chain restriction. In another patient, disease recurred with a polytypic cutaneous plasma cell infiltrate. Polymerase chain reaction (PCR) revealed clonal immunoglobulin heavy chain gene rearrangements in eight of 13 cases, which was confirmed by Southern blot analysis in three samples. Clonal T-cell receptor chain gene rearrangements were not detected. Disease progression to overt malignant lymphoma did not occur within the follow-up period of up to 12 years, but recurrent disease was seen in three patients. Our data indicate that cutaneous lymphoid hyperplasia with monotypic plasma cells is a biologically distinct clinicopathological entity.

Adolescent↗
PubMed1994

[Adenoid cystic sweat gland carcinoma. A clinicopathologic and immunohistochemical study].

Adenoid cystic carcinoma of the skin is one of the rarest sweat gland tumours. We have studied two cases of adenoid cystic sweat gland carcinoma clinically, histologically and immunohistochemically. One tumour was located on the occiput of an 18-year-old male patient, while the other developed on the back of a 49-year-old woman. Histologically, both carcinomas were characterized by basaloid tumour cells showing the typical adenoid-cystic growth pattern. The cells were arranged in solid, cribriform, tubular and cystic aggregates, which were surrounded by mucoid, Alcian blue material. Immunohistochemically, the tumour cells showed coexpression of cytokeratins typical of stratified epithelia (CK1/5/10/14) and cytokeratins of the simple epithelial type, namely CK7, CK8, CK18, and CK19. Coexpression of these cytokeratins is usually observed in normal fetal sweat glands, but not in adult sweat glands.

Adolescent↗
PubMed1994

[Value of nucleolus organizer regions (AgNORs) in dermatologic oncology].

Nucleolus-organizing regions (Ag-NORs) are silver-stained loops of DNA transcribing to ribosomal RNA. Quantitative analysis helps to differentiate normal tissue from malignant tissue and can be used for diagnosis in several kinds of tumours. The analysis of AgNORs can also be used in dermatopathology for diagnostic and prognostic purposes. Apart from skin tumours such as basal, cell carcinomas and squamous cell carcinomas, this technique is of interest principally for melanocytic lesions. Benign naevi can be distinguished from malignant melanomas by simple counting of the AgNOR dots. For the differentiation of dysplastic naevi, Spitz naevi and malignant melanomas, this parameter alone is not sufficient. By combination of several AgNOR parameters (number, size, pattern of dispersal) only, significant differentiation could be achieved. The prognostic value of AgNORs remains to be examined.

Basal Cell Carcinoma↗
PubMed1994

p53 protein in benign and malignant sweat gland tumors.

Mutation of the p53 gene and increased levels of p53 protein are among the most frequent alterations in human cancers. To date, very little is known about the mechanisms underlying the development of sweat gland carcinomas. In this study, we analyzed 43 benign and 39 malignant sweat gland tumors for p53 protein level using the antibody PAB1801. Nine (23%) of 39 sweat gland carcinomas were positive for p53 protein. Among these carcinomas, six of 12 cases of extramammary Paget's disease were positive using immunohistochemistry. No other correlation between tumor subtype and p53 reactivity was detected. Among 43 benign sweat gland tumors, only one case displayed staining for p53. We conclude that p53 protein plays a role in a subset of sweat gland tumors, especially in extramammary Paget's disease.

Adenocarcinoma↗
PubMed1994

Immunohistochemical demonstration of myoepithelial cells in sweat gland carcinomas.

Although myoepithelial cells are detectable in many benign sweat gland tumours, little is known about their role in sweat gland carcinomas. To specifically demonstrate myoepithelial cells, paraffin sections from 46 sweat gland carcinomas were stained, using a standard avidin-biotin-peroxidase complex method, with the monoclonal alpha-smooth muscle actin antibody 1A4. Myoepithelial cells were not found in adenoid cystic eccrine carcinoma (n = 2), malignant nodular hidradenoma (n = 2), porocarcinoma (n = 4), extramammary Paget's disease (n = 12), sclerosing sweat duct carcinoma (n = 4) or in adenosquamous-mucoepidermoid carcinoma (n = 1). In contrast, myoepithelial cells were demonstrated in two of eight apocrine adenocarcinomas, one of six mucinous eccrine carcinomas and two of seven eccrine adenocarcinomas. In all these tumours myoepithelial differentiation was found in peripheral cells of solid tumour islands, or in basal cells of tubular structures. However, in most areas of the tumours, myoepithelial layers were discontinuous. Cells in the centre of solid tumour nodules, and luminal cells of tubular structures, were negative for alpha-smooth muscle actin. In analogy to breast tumours, in which malignancy and invasiveness correlate with scattered or absent myoepithelial cells, we suggest that disrupted myoepithelial layers in sweat gland carcinomas may be interpreted as a loss of the invasion barrier.

Actins↗
PubMed1994

Coexpression of cytokeratin and vimentin intermediate filaments in benign and malignant sweat gland tumors.

The coexpression of cytokeratin and vimentin intermediate filaments has been immunohistochemically evaluated in 124 benign and malignant sweat gland tumors of various types in comparison to normal sweat glands. In addition, all neoplasms have been stained by an antibody to alpha-smooth muscle actin. Epithelial cells reacted with the pan-cytokeratin antibody lu-5. In normal sweat glands, vimentin immunoreactivity was restricted to myoepithelial cells and to some cells of the coiled duct. In benign sweat gland tumors (n = 88), coexpression of vimentin and alpha-smooth muscle actin was frequently found in basal cells of neoplasms considered to differentiate towards the secretory coil of the eccrine or apocrine gland. These included eccrine spiradenoma, apocrine cystadenoma, hidradenoma papilliferum, syringocystadenoma papilliferum, and cylindroma. Thus, in these tumors, vimentin-reactive cells corresponded to myoepithelial cells. Vimentin-positive cells were also found in 14 of 36 sweat gland carcinomas, including 1 case of sclerosing sweat duct carcinoma, 1 case of porocarcinoma, 4 cases of eccrine adenocarcinoma, 1 case of mucinous eccrine carcinoma, and 5 cases of apocrine adenocarcinoma. Co-expression of vimentin and alpha-smooth muscle actin was observed in some cells of eccrine and apocrine adenocarcinomas. Therefore, in these neoplasms, some vimentin-positive cells appear to represent myoepithelial cells. In contrast, vimentin-positive cells in all other malignant tumors did not express alpha-smooth muscle actin. Our results indicate that coexpression of cytokeratin and vimentin may be frequently found in a variety of benign and malignant sweat gland tumors. In the majority of these neoplasms, vimentin-positive cells correspond to myoepithelial cells. Because vimentin is not specific for myoepithelial cells, additional stains for alpha-smooth muscle actin should be performed to prove the myoepithelial nature of vimentin-positive cells.

Humans↗
PubMed1994

UV-A-provoked localized bullous pemphigoid.

A 71-year-old woman had noticed the development of blisters on her forehead 4 months before she was referred to our department. Treatment with oral corticosteroids resulted in complete healing, but new blisters subsequently developed on the face, neck and backs of the hands. After the possibility of phototoxic and photoallergic reactions, as well as an abnormal porphyrin profile, had been excluded, the diagnosis of bullous pemphigoid was made by histological and direct immunofluorescent examination. UV-A provocation on the upper arm produced lesions histologically and immunohistochemically typical of bullous pemphigoid. Of particular importance was the fact that the blisters were limited strictly to light-exposed skin areas.

Aged↗
PubMed1993

Deposits of paraprotein in small vessels as a cause of skin ulcers in Waldenström's macroglobulinemia.

A 71-year-old man presented with epistaxis and large ulcers on arms and legs. A monoclonal IgM-kappa gammopathy and high levels of cryoglobulins were found. Histology of the affected skin showed deposits of paraprotein in the small vessels, causing luminal obstruction. This in turn caused ischemic skin lesions, which were successfully treated with cortisone (fluocortolone 100 mg/day every second day) and cyclophosphamide (100 mg/day).

Aged↗
PubMed1993

Spiradenomas in Brooke-Spiegler syndrome.

Brooke-Spiegler syndrome is an autosomal dominantly inherited disease characterized by the development of multiple trichoepitheliomas and cylindromas. Among other neoplasms that may also occur in Brooke-Spiegler syndrome are basal cell carcinomas and spiradenomas. Spiradenomas and cylindromas have so many features in common that they have been regarded as variants of the same neoplasm. This assumption was supported by the occurrence of both types of lesions in Brooke-Spiegler syndrome. We report a case of Brooke-Spiegler syndrome in which spiradenomas were found in the immediate vicinity of trichoepitheliomas and in continuity with follicles. Because of the embryonic relationship between follicles and apocrine glands, these features indicate that spiradenomas are apocrine neoplasms. We conclude that Brooke-Spiegler syndrome is an inherited disease that affects the folliculosebaceous apocrine unit.

Adenoma, Sweat Gland↗
PubMed1993

[Multiple disseminated glomus tumors (glomangioma). Immunohistochemical analysis and differentiation from viscerocutaneous hemangiomatosis].

A 25-year-old patient presented with multiple disseminated asymptomatic bluish nodules, which had been present since childhood. Histological examination revealed vascular cavities surrounded by round to oval eosinophilic cells. Positive immunohistochemical staining with alpha-smooth-muscle antigen (alpha-SMA) and vimentin confirmed the diagnosis of multiple disseminated glomus tumours of the vascular type. Tumour cells were surrounded by a network of type IV collagen. In contrast antibodies against the intermediate filament protein desmin and the endothelial markers BMA 120 and anti-von Willebrand factor revealed no staining of the glomus cells. This was the first immunohistochemical investigation of a glomus tumour of vascular type. Immunohistochemical staining of these glomus cells revealed no difference from other histological types of glomus tumours.

Adult↗
PubMed1993

[Malignant blue nevus].

A 35-year-old male patient suffering from a malignant blue naevus is presented. An uncommon melanocytic naevus and malignant melanoma were considered in the differential diagnosis. The final diagnosis was established by histological examination. Immunohistochemical studies showed a strongly positive reaction of the tumour cells for vimentin and S-100 protein. In addition, tumour cells reacted with the antibody HMB-45.

Adult↗