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Nerve sheath myxoma (NSM) is a rare cutaneous neoplasm, the histogenesis of which is controversial. Fifteen cases of NSM were studied by routine light microscopy and with a broad panel of immunohistochemical stains. NSM were classified into three groups based on cellularity, mucin content and growth pattern. 1) The hypocellular (myxoid) type (5/15 cases) showed frequent encapsulation or sharp circumscription. Immunohistochemically this type was strongly positive for S-100 protein and collagen type IV and variably positive for epithelial membrane antigen. 2) The cellular type (4/15 cases) had scant mucin and ill-defined nodular or infiltrating growth. Immunostaining showed positive reaction for neuron specific enolase (2/4), Leu-7 (1/4) and smooth muscle specific actin (2/4), and was negative with the other antibodies. 3) The "mixed type" (6/15 cases) had variable cellularity and mucin content with poor demarcation and variable immunolabeling. We conclude that: 1) there are major light microscopic and immunohistochemical differences between the classical hypocellular (myxoid) and the cellular forms of NSM (neurothekeoma); 2) while the immunohistochemical results support the presence of nerve sheath differentiation in the classical forms of NSM, and to some extent in the mixed forms, there is an absence of convincing evidence of neural differentiation in the cellular variant by either light microscopy or immunohistochemistry; 3) the variable immunophenotypes suggest that differentiation other than neural may take place in CNT.

Background: Histologic distinction of dermatofibrosarcoma protuberans (DFSP) from fibrous histiocytoma (FH) may be difficult. In addition, differential diagnosis is hampered by the lack of appropriate immunohistochemical markers that reliably distinguish between these two entities., Objective: This study is aimed at the introduction of a monoclonal antibody (anti-human progenitor cell antigen-1; anti-CD34) that distinguishes between DFSP and FH in formalin-fixed, paraffin-embedded tissue., Methods: Paraffin-embedded specimens of DFSP, FH, and other soft-tissue tumors were investigated for CD34 expression by anti-human progenitor cell antigen-1/alkaline phosphatase-antialkaline phosphatase immunostaining., Results: Strong CD34 reactivity was present in each DFSP (n = 19) but was consistently absent from FH (n = 45) and other soft-tissue tumors (n = 47)., Conclusion: CD34 immunostaining of paraffin-embedded specimens may be useful in differentiating between DFSP and FH.

Pigmented epidermotropic breast carcinoma has to be included in the differential diagnosis of pigmented lesions of the breast. Two rare cases of pigmented Paget's disease and pigmented metastatic breast carcinoma are presented, which mimicked malignant melanoma in both clinical and histological criteria.

A new plasmid, pGA1, has been isolated from Corynebacterium glutamicum LP-6, and its detailed restriction map has been prepared. The 4.9-kb plasmid has a G + C content of 57%. It replicates in C. glutamicum ATCC13032 and is compatible with the three other plasmids, pCC1, pBL1 and pHM1519, commonly used for vector construction for amino acid-producing corynebacteria. Fusions of pGA1 with different Escherichia coli replicons (transferred from E. coli to Corynebacterium via transformation of spheroplasts or by filter mating experiments with intact cells) are shown to be suitable as shuttle plasmids; some of them are highly stable in C. glutamicum, even when propagated without any selection pressure.

Lymphoepithelioma-like carcinoma of the skin (LECS) is a rare cutaneous tumour with histological features resembling those of Epstein-Barr virus-induced nasopharyngeal carcinoma. An LECS tumour may mimic lymphoid follicles in its composition. Its distinct histological pattern, however, is based on syncytial nests and cords of large pale-staining epithelial tumour cells surrounded by a dense lymphoplasmacytic infiltrate. Tumour cells show conspicuous vesicular nuclei with delicate chromatin and few prominent nucleoli. Histological differential diagnosis must include malignant lymphomas, Merkel cell tumour, squamous cell carcinoma and cutaneous metastasis of lymphoepithelioma. Immunostaining with anticytokeratin antibodies is highly significant in the differential diagnosis. Histological and immunohistological findings in an LECS removed from the upper lip of a 56-year-old women are reported. Serologic investigations did not indicate EBV-associated tumour growth.

Angioendotheliomatosis proliferans systemisata (AEPS) is a rare disease entity characterized by a predominantly intravascular proliferation of tumour cells. Two forms of AEPS are differentiated: a very rare, benign and self-limiting form, which is endothelial in origin, and a more common, malignant form, which is an angiotropic intravascular malignant B-cell lymphoma. Histological and immunohistological investigations of the malignant form of AEPS are presented: In a 69-year-old woman cutaneous lesions appeared 5 months before the diagnosis of B-immunoblastic lymphoma. In a 57-year-old woman lesions were observed simultaneously with the relapse of a high-grade malignant B-cell lymphoma. Immunohistological identification of the proliferating cell type made diagnosis of intravascular B-cell lymphoma possible in paraffin-embedded biopsies.

By UV and NTG mutagenesis numerous auxotrophic, antibiotic-resistant and melanin-negative mutants were isolated from Streptomyces michiganensis DSM 40,015 which proved to possess a efficient photoreactivation system. Using a mel- test strain with three auxotrophic markers and a antibiotic resistance for crosses with numerous prototrophic mel- strains three classes of mutants (melA, melB and melC) could be found. This classification was further supported by a series of crosses. The melC locus seemed to correspond to the melC locus of S. glaucescens which contains the tyrosinase structural gene.

Solitary encapsulated neuroma (EN) is a true neuroma that is seldom diagnosed clinically. EN is the most frequently excised benign neuroma of the skin and has to be included in the differential diagnosis of small nodular facial tumours of middle-aged people. We report histological studies of 79 EN. EN are distinctive true neuromas that can easily be distinguished from all other benign neural neoplasms except the neuromas in the multiple mucosal neuroma syndrome.

The host range of the virulent bacteriophage Cog among several strains of amino acid-producing corynebacteria is limited to Corynebacterium glutamicum LP-6. Cog is a typical corynephage of the Siphoviridae family (B1 morphotype) with an isometric head of 52 nm and a medium length, striated tail of 190 nm. It has a linear genome of 39.7 kb with cohesive ends and 53% G + C; a restriction map is presented, including regions of DNA homology (by hybridization) with the inducible phage particle phi GA1 from Brevibacterium flavum.

Three species-specific, temperate actinophages of Streptomyces coelicolor Müller, phi SC623, phi SC347 and phi SC681, were compared with respect to host range, virion structure, antiserum cross-inactivation, DNA-restriction pattern, DNA hybridization, and DNA base composition. The restriction map of phi SC623 (57 kb) was established with eight restriction enzymes; the homologies of this phage with phi SC347 and phi SC681 suggested that it might be a hybrid phage composed of approximately equal parts homologous to one of the other two phages. No homology was detected between phi SC623 and R4, a temperate, wide-host-range phage which can also lysogenize S. coelicolor Müller.

Eighteen related strains of Arthrobacter, Brevibacterium and Corynebacterium were used as indicator strains in an attempt to isolate corynephages from a large number of soils and from waste-water samples. Although no phages capable of producing plaques were isolated, one of the indicator strains used, Brevibacterium flavum ATCC 14067, was lysogenic for the inducible phage phi GA1. This phage was not observed to form plaques on any of the strains tested. phi GA1 is of B1-morphotype with a linear double-stranded DNA genome of 48.1 kb with cohesive ends; a restriction map is presented.

The peroxidase-antiperoxidase (PAP) technique allows the detection of immunoglobulin deposits in formalin-fixed, paraffin-embedded tissue. The PAP technique may be used as an alternative to the direct immunofluorescence method on frozen, unfixed skin. In addition, the PAP technique is suitable for retrospective evaluation of histological samples.

Palmar and finger varicosis is a common abnormality of the veins in the elderly. This often overlooked age-related condition is illustrated by three observations.

Investigations of dyshidrotic eruptions of various causes were done by conventional and electron microscopy. In all cases, the histological patterns were identical. The dyshidrotic vesicle is an intraepidermal, spongiotic lesion. The intraepidermal part of the eccrine sweat duct (acrosyringium) is not altered even by spongiosis. As the acrosyringium does not take part in formation of a dyshidrotic vesicle, the term "dyshidrosis" has to be regarded as a misnomer. Dyshidrosis is nothing but spongiotic dermatitis modified by the distinctive characteristics of palmar and plantar skin.

The adamantinoid basal cell epithelioma is a clinically uncharacteristic but histologically typical variant of basal cell epithelioma characterized by a meshwork of stellate tumor cells.

A 54-year-old male had erythema chronicum migrans (ECM), lymphocytic meningitis, and intense pain radiating along the distribution of the corresponding dermatomal segments. Neurologic involvement, described as Bannwarth syndrome or meningopolyneuritis Garin-Bujadoux-Bannwarth, is a typical late manifestation of ECM infection and requires high-dose intravenous penicillin therapy.

The comparison of the Saccharomonospora phages phi SaC1, phi SaG1, phi SaV1, phi SaV2, phi SaV3, and Tm1 demonstrated that they all belong to a single group of closely related actinophages: they were similar with regard to host range, virion mophology (B1 type), genome length (43-45 kb), and GC content of their genomes (63, 3% G + C). Furthermore, DNA-DNA hybridization showed that the phage genomes had a high degree of homology to each other. The phages are, therefore, proposed as representatives of a new bacteriophage species in the sense of the ICTV.

After microwave irradiation with simultaneous field anesthesia, acute ulceration was observed. The danger of this complication following irradiation of areas with reduced sensitivity is stressed.

Alcaligenes spec. strain In 3 was isolated from an enrichment culture with indole inoculated with activated sludge. The organism was able to grow with indole as sole source of carbon and nitrogen. During growth with this substrate indigo and anthranilate accumulated in the culture broth. By measurement of the oxidation of intermediates (O(2)-uptake) and determination of the activity of enzymes responsible for ring cleavage the following pathway for indole degradation could be established: indole → indoxyl → isatin → anthranilate → gentisate → maleyl pyruvate → fumaryl pyruvate → fumarate + pyruvate. - Alcaligenes spec. strain In 3 was also able to grow with various aromatic compounds; these were degraded by ortho- or meta-cleavage or via the gentisinic acid pathway., (Copyright © 1983 Gustav Fischer Verlag, Stuttgart/New York. Published by Elsevier GmbH.. All rights reserved.)

Useful biochemical markers for the classification of Actinomycetales are: 1. DL- or LL-diaminopimelic acid in the peptidoglycan, 2. sugar composition of polysaccharides, 3. fatty acid spectrum of cell lipids. The occurrence of various kinds of branched fatty acids and of unsaturated fatty acids is of special value.

Among a total of 270,000 skin biopsies, 87 desmoplastic trichoepitheliomas were identified, 11 (12.6%) of which were associated with nevocytic nevi. Histopathologically we found nevocytes next to horn cysts and thin strands of monomorphous basaloid neoplastic cells in a dense desmoplastic stroma. The frequency of this association suggests that it may be a combined malformation rather than a chance occurrence. On clinical examination most cases had been misdiagnosed as basal cell carcinomas. Most biopsies were taken from the faces of fairly young women.

The DNA of phi FR114, a temperate phage of the thermophilic actinomycete Faenia rectivirgula, was hybridized with the genomes of 11 different phages of Faenia and Saccharopolyspora. This revealed several regions (modules) within the phi FR114 DNA which were distributed independently among the genomes of the other phages. The genome of the lytic phage 121, originally described for Sap. erythraea, exhibited a similar modular organization. So far no functions of the possible modules are known.

Dysfunction of sweat glands and acrosyringia are not involved in the pathogenesis of dyshidrosis. Clinically, dyshidrotic dermatitis (atopic, toxic, contact allergic, hematogen-allergic) and dyshidrotic tinea should be differentiated. Therapeutic possibilities comprise symptomatic topical and systemic treatment, whereas causal treatment is only possible in cases of tinea.

When myo-inositol is present in a growing culture of Streptomyces griseus the yield of streptomycin is increased, and the amount of carbon-14-from uniformly labeled glucose-incorporated into the streptidine and streptobiosamine moieties of streptomycin is lowered by 41 percent and 21.7 percent, respectively. These results present strong indirect evidence for the participation of myo-inositol or its metabolic products in streptidine biosynthesis.

Myo-inositol, especially in combination with arginine, enhances streptomycin production. Compounds which show structural relationship with myo-inositol are ineffective.Myo-inositol decreases the incorporation of C(14)-glucose into streptomycin, particularly into streptidine. This effect suggests that myo-inositol is a precursor of the streptidine ring. Methionine stimulates antibiotic production in a synthetic medium but proves to be unfavorable in a complex medium. The gamma- and delta-isomers of hexachlorocyclohexane inhibit streptomycin formation. The formation of streptomycin by washed mycelium was studied. Essentially the same results were here obtained as with growing cultures.