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D Stiller

Publications and source records attributed to D Stiller.

At least 73 records · Page 4Linked to original sources
PubMed1990

DNA probes distinguish geographical isolates and identify a novel DNA molecule of Babesia bovis.

A genomic DNA library of Babesia bovis was screened to identify DNA probe candidates for direct detection of the parasite. Two sequences, Bo6 and Bo25, had the highest sensitivity and further analysis revealed unique characteristics of each of these. Neither sequence hybridized detectably to bovine DNA. Bo6 detected 100 pg of both a Mexican and an Australian isolate of B. bovis, but Bo6 also detected 1.0 ng of Babesia bigemina DNA under identical conditions. A unique characteristic of Bo6 is that it hybridizes to an apparent 7.4-kilobase DNA in undigested genomic DNA of both B. bovis and B. bigemina. The sequence is well conserved between the 2 geographic isolates of B. bovis, but it is apparently divergent in B. bigemina. Bo25 did not hybridize detectably to bovine or B. bigemina DNA. This sequence detected 100 pg of homologous B. bovis Mexican isolate DNA, but the sensitivity was reduced to 1 ng for the Australian isolate DNA. The restriction enzyme profile of the Bo25 sequence in genomic DNA differed markedly in the number, size, and intensity of bands between the 2 B. bovis geographic isolates tested. Thus, the Bo25 sequence can distinguish geographic isolates of B. bovis.

Animals↗
PubMed1989

Detection of colonies of Anaplasma marginale in salivary glands of three Dermacentor spp infected as nymphs or adults.

Salivary glands from males of 3 Dermacentor species (D andersoni, D variabilis and D occidentalis) that were infected with either the Virginia or Idaho isolate of Anaplasma marginale as nymphs or adults were examined for colonies of A marginale by use of light and electron microscopy. Prior to dissection of salivary glands, exposed ticks were held at 25 C for 15 to 18 days, followed by a 3-day incubation at 37 C. Ticks of 2 species transmitted A marginale to calves; the third tick species was confirmed infected by demonstration of typical colonies in tick gut cells, but transmission was not attempted; Colonies of A marginale were seen with light microscopy in salivary glands of all 3 species of ticks; they were located in acinar cells that contained simple granules. Colonies varied morphologically from small, compact ones to larger structures that contained distinct organisms and often were adjacent to the host cell nucleus. Electron microscopy confirmed that the colonies were rickettsial organisms. Morphologic features of A marginale varied and included reticulated forms, forms with electron-dense centers, and small particles; these various forms were similar to those described previously in midgut epithelial cells of ticks. We believe that the organism seen within tick salivary glands may replicate in the glands before its transmission to the vertebrate host.

Anaplasma↗
PubMed1988

Detection of Anaplasma-marginale-infected tick vectors by using a cloned DNA probe.

Anaplasmosis is the most widely distributed of several important tick-borne diseases that constrain cattle production throughout much of the world. Evaluation of the effectiveness of disease control strategies that integrate vaccination with tick control requires the ability to monitor tick and cattle infection rates. To detect Anaplasma marginale in ticks and bovine erythrocytes, a 2-kilobase DNA fragment from a cloned A. marginale gene coding for a surface protein having a Mr of 105,000 was prepared and evaluated as a probe. The probe was species specific and detected A. marginale DNA derived from infected bovine erythrocytes and adult Dermacentor ticks infected either as nymphs or adults. Tick infection was confirmed by microscopy and test feeding on a susceptible calf. The sensitivity of the probe is suitable for detecting infected ticks in experimental and field epizootiology studies.

Anaplasma↗
PubMed1988

[Cellular differentiation in storiform-pleomorphic malignant fibrous histiocytomas. An electron microscopic study of histogenesis].

The most common form of malignant fibrous histiocytoma is the storiform-pleomorphic subtype composed of spindle-shaped fibroblast-like cells, mononucleated histiocytic elements and a changing amount of pleomorphic giant cells. In relation to the changing cellular structures 14 pleomorphic-storiform malignant fibrous histiocytomas were investigated electronmicroscopically. In all tumors several types of cells varying in shape, and size as well as in organelle composition could be demonstrated: 1. Undifferentiated cells, which are relatively small and have a scanty cytoplasm with few organelles. 2. Fibroblast-like cells with well developed rough endoplasmic reticulum, mostly arranged in a storiform pattern. 3. Myofibroblasts corresponding to fibroblasts and showing bundles of thin filaments (4 to 6 nm) with focal dense bodies in the peripheral area of the cytoplasm. 4. Histiocyte-like cells characterized by filopodia-like projections and abundant cytoplasm containing lysosomes and phagolysosomes and also lipid droplets. 5. Chimeric cells, which are intermediate forms with features of fibroblast-like and histiocyte-like tumor cells. 6. Multinucleated tumor giant cells which can be subdivided into fibroblast-like and histiocyte-like types and intermediate forms. On the basis of our ultrastructural studies the storiform pleomorphic malignant fibrous histiocytoma is interpreted as a tumor of an undifferentiated mesenchymal cell with the potency of fibroblastic or histiocytic differentiation. The origin of this cell is uncertain. Dedifferentiation of a differentiated connective tissue cell (fibroblast, pericyte) into a proliferating undifferentiated precursor cell is discussed.

Cell Differentiation↗
PubMed1988

[Immunohistochemical detection of lysozyme and alpha-1-antichymotrypsin in fibrohistiocytic tumors].

Lysozyme and alpha-1-antichymotrypsin depositions were recorded by means of the PAP technique from benign and malignant fibrohistiocytic tumours. These depositions were seen in relation to lesions with histiocytic reactions. The findings indicate that the detection of these markers support the solution of problems of differential diagnosis. An important role is particularly played by demonstration in fibroblastic elements within the neoplasm proper. The results also suggest the possible existence of an undifferentiated precursor cell.

Diagnosis, Differential↗
PubMed1988

[Growth patterns of juvenile nasopharyngeal fibromas. A histological analysis on the basis of 40 cases].

Juvenile nasopharyngeal angiofibroma is a unique process characterized by an exclusive localization in the nasopharynx of young male patients, and a typical histological pattern composed of angiomatous and fibrous structures. Forty tumors of patients 7 to 25 years of age were investigated. The tumors showed a characteristic zonal organization. Apart from the superficial epithelium the lesions can be subdivided into a subepithelial myxoid-fibrous zone followed by a proliferative capillary fibroblastic cambium layer. In the latter, either the capillary component or the fibroblasts can prevail. The main part is composed of sinus-like vascular channels and a fibrous component. The gaping vascular channels differing in caliber are lined by a single layer of epithelium and surrounded by single or mostly an incomplete rim of smooth muscle cells. Elastic fibres are always lacking. The fibrous component exhibits a changing cellularity and fibre content. Myxoid foci can be encountered, often associated with a pleomorphic cell pattern. Generally, however, fibre structures and foci or large areas of hyalinization predominant in direction to the central parts. In older lesions the fibrous tissue is prevailing. The capillary fibroblastic cambium zone disappears and areas of hyalinization are enlarged. In five cases relapses showing the same structural features were observed. Juvenile nasopharyngeal angiofibromas are discussed as a specific but non-autonomous proliferating growth process which is characterized by 1. specific age and sex incidence, probably in relation to hormones, 2. typical histological pattern and cytological criteria, including local infiltration of the surrounding musculature and bones, 3. origin in the same region corresponding to the membrana buccopharyngea and constant blood supply by the arteria maxillaris interna, or its end artery, the arteria sphenopalatina. According to the corpus cavernosum-like structures, comparable to erectile tissue, the nasogenital relations are discussed. Juvenile nasopharyngeal angiofibromas are defined as a specific clinicopathological entity.

Adolescent↗
PubMed1988

[Epithelioid hemangioendothelioma of the soft tissue. Histology and ultrastructural cytology].

Described in this paper is a case of epithelioid haemangioendothelioma of soft tissue localised in the subcutis of the upper arm of a 47-year old man. The tumour was histologically characterized by cords and nests of plump epithelioid cells separated from each other by typical myxohyaline stroma. Light microscopy revealed also definite vasoformative areas and solid regions with vacuolization which were indicative of so-called intracytoplasmic vacuoles. Atypical nuclei were conspicuous findings. Ultrastructural and immunohistochemical investigations demonstrated the endothelial origin of the lesion. Immunohistochemical investigations also revealed the presence of cellular areas which produced positive response to "factor-VIII-associated antigen". Ultrastructurally the tumour cells exhibited densely packed microfilaments, 8 nm to 10 nm in thickness, and intracytoplasmic vacuoles. The latter were lined and delimited by single membranes, and some of these exhibiting luminal microvilli. The tumour cells exhibited typical pinocytotic vacuoles, with the cords or nests being encircled by thin basal membranes. Typical Weibel-Palade bodies were detectable in some cells. Also recordable from certain cells were intracytoplasmic crystalloid inclusion bodies of a kind never described before in the context of tumour cells of epithelioid haemangioendothelioma. Those inclusions were composed of substructural units of parallel electrodense lines, 19nm to 21nm in periodicity. The nature of epithelioid haemangioendothelioma and its relations with intravascular bronchiolo-alveolar tumours (IVBAT) and myxoid angioblastomatosis of bone were discussed in some detail.

Adult↗
PubMed1988

[Immunohistochemical demonstration of fibronectin in the human placenta].

The distribution pattern of fibronectin in the human placenta has been studied using the indirect immunoperoxidase (PAP) technique on formalin fixed paraffin embedded tissue samples. Fibronectin was demonstrated as intensely stained fibrillar or strand-like structures on the endothelial cells of blood vessels and on the amniotic epithelium. The most interesting fibronectin staining result, however, was found in the cytotrophoblast cells and in the bud-like structures of the syncytiotrophoblast. The results were discussed with regard to differentiation and proliferation in course of placental development.

Female↗
PubMed1988

[Morphological pathology of classic Kaposi's sarcoma. Ultrastructural studies and reflections on histogenesis].

Histological and electron-microscopic studies were conducted into biopsy material from cases of what is called the classical type of idiopathic Kaposi's sarcoma without acquired immunodeficiency syndrome. Ultrastructural analysis was conducted, with the view to characterizing a possible progenitor cell from which the angioblastic and fibroblastic elements were likely to originate. The biopsy material had been obtained from two males, aged 86 or 83 years, who had been afflicted with the disease for 18 or 8 years. The nodular lesions were typical of Kaposi's sarcoma and were, histologically, made up of variable mixtures of vascular and spindle cell elements. The angiomatous structures were a capillary meshwork or sinusoidal patterns lined by atypical endothelial cells. The spindle cell areas contained large numbers of slit-like spaces which were without endothelial lining but were stuffed with erythrocytes. Flattened endothelioid cells were recordable from semi-thin-sections of some clefts. Haemosiderin was, typically, deposited in places. Electron microscopically, the endothelial cells of vascular channels exhibited varying amounts of characteristic organelles, such as Weibel-Palade bodies, microfilaments and pinocytotic vesicles as well as basal membranes. Cells with typical endothelial markers, too, were detectable in solid sprouts or in capillary-like differentiations with narrow or small lumina. The spindle cell tumour areas consisted of fibroblastic cells with plenty of rough endoplasmic reticulum and surrounded by material of basal membrane nature. Also visible were solid, sprout-type multilayer cell complexes surrounded by basal membranes which exhibited undifferentiated or primitive cellular forms, endothelioid and pericytic. Transitional forms from these complexes to the above vascular tumours or the spindle-cell formations were detectable. These ultrastructural findings might be interpreted to the effect that an angioblastically determined mesenchymal cell, a so-called endothelioblast, was thinkable and was discussed as the precursor cell of atypical vascular and spindle cell proliferation in Kaposi's sarcoma.

Aged↗
PubMed1988

[Ultrastructural organization of cell characteristics relevant to diagnosis in rhabdomyosarcomas].

Rhabdomyosarcomas may be easily diagnosed by light microscopy when tumor cells exhibit cross striations typical of skeletal muscle cells. But in many cases the histological diagnosis is difficult because the tumors are predominantly composed of undifferentiated elements and only single cells can be seen which show an eosinophilic cytoplasm suggesting different steps of a possible rhabdomyoblastic differentiation. Using the electron microscope seven embryonal rhabdomyosarcomas, one alveolar rhabdomyosarcoma including one lymph node metastasis and one pleomorphic rhabdomyosarcoma were analysed in order to study the submicroscopical organization of diagnostic cellular features, resp. the distribution and arrangement of cytoplasmic filaments. The following lines of cellular differentiation could be distinguished: 1. Development of differentiated myoblasts and satellite cells: -- primitive, undifferentiated tumor cells: small round cells with scanty cytoplasm containing few thin filaments (4 to 6 nm) and intermediate-type filaments (10 nm), -- round or slightly spindle-shaped myoblast-like tumor cells: cells with moderate cytoplasm exhibiting irregularly arranged thin and intermediate-type filaments and only some thick filaments (15 nm), -- myotube-like cells: long extended cells (strap shaped cells) revealing thin and thick filaments, Z-line material and different stages of myofibrillar organization, -- well-differentiated myoblasts: long extended cells showing typical cross-striations which correspond to well-formed sarcomeres with I-bands (Z-lines with extending thin filaments) and A-bands, which are subdivided into H- and M-bands, -- satellite cells of typical ultrastructure associated with differentiated myoblasts by a common basement membrane present in one case. 2. Development of aberrant myoblasts and giant cells: -- round myoblasts: cells with increased cytoplasm containing thin and thick filaments, primitive Z-lines, which were not organized into sarcomeres as well as unaligned sarcomeres, -- large round myoblasts and giant cells: cells with abundant cytoplasm containing irregularly distributed thin and thick filaments, primitive Z-lines and haphazardly arranged sarcomeres, which did not appear as cross-striations by light microscopy. The ultrastructure of tumor cells is discussed with regard to the degree of differentiation and their light microscopic appearance. The scale of cellular features in rhabdomyosarcomas could be also correlated with normal fetal myogenesis. Furthermore this confirms the important role of electron microscopy in the differential diagnosis of other small, primitive and dark-cell tumors.

Adolescent↗
PubMed1988

[Histologic diagnosis and ultrastructural cytology of epithelioid sarcoma].

Epithelioid sarcoma is a rare but distinctive soft tissue tumor showing characteristic histologic features associated with a typical course, but there is still some debate as to its histogenesis. Two cases of this unique tumor were analyzed using the electron microscope. Light microscopically the diagnostically relevant cell type is oval to polyhedral exhibiting a dense eosinophilic cytoplasm. In such epithelioid cells the cytoplasm may sometimes be completely filled with an inclusion-body like hyaline eosinophilic material. Ultrastructurally the most striking feature are abundant intermediate-type filaments in these eosinophilic cells. While none of the electron microscopic findings is specific, the accumulation of the intermediate-type filaments in conjunction with the other cellular features described in sufficiently consistent and distinctive and can thus be used for confirming the diagnosis. In formalin-fixed specimens the electron microscopical investigation may be helpful in everyday diagnosis. The suggestion from the literature that epithelioid sarcoma is related to the synovial sarcoma can not be supported by our ultrastructural findings.

Adult↗
PubMed1987

Fibronectin in relation to growth patterns of fibrohistiocytic tumours--an immunohistochemical study of benign and malignant fibrous histiocytomas.

Benign and malignant fibrous histiocytomas are composed of an admixture of fibroblast-like and histiocyte-like cells and of a changing amount of fibre structures which tend to be arranged in a so-called storiform pattern. In order to study the organization of the extracellular matrix, the distribution of fibronectin was investigated immunohistochemically. Using the PAP technique and the indirect immunofluorescence method, paraffin sections of formaldehyde fixed tissue specimens of 25 tumours (12 benign fibrous histiocytomas, 12 malignant fibrous histiocytomas, and 1 atypical fibroxanthoma) were studied. A pretreatment with hyaluronidase and proteolytic enzymes (trypsin, pronase, pepsin) was performed to unmask the antigen. Best results were obtained with pronase E or, sometimes even better, by employing a combination of pronase E and hyaluronidase. Generally fibronectin could be demonstrated in the matrix substances of fibrohistiocytic tumours, but the immunohistochemical staining patterns of benign and malignant tumours differed. In benign fibrous histiocytomas, a regular distribution of fibronectin was found in cellular areas. Parallel to formation of collagen fibres, the reaction decreased and in dermatofibromas showing abundant hyalinized collagen the staining proved to be quite weak. In malignant fibrous histiocytomas, the immunostaining was very irregular. In cellular areas consisting of spindle cells, an intense reaction could be observed. Tumours with storiform or fascicular fields exhibit a delicate network of fibronectin encircling individual fibroblast-like cells. In the course of fibre formation, the matrix staining for fibronectin revealed a distribution similar but not identical with that obtained with the reticulin stain. Simultaneous to the occurrence of collagen fibre bundles, fibronectin decreased and in areas of hyalinization the staining was considerably diminished. In areas of undifferentiated small cells, in myxoid zones as well as foci of xanthoma cells, and in pleomorphic portions the immunostain was negative. The distribution in atypical fibroxanthoma is similar to that observed in storiform and pleomorphic variants of malignant fibrous histiocytomas. The results support the suggestion that fibronectin is the first sign of the typical basic pattern of fibrohistiocytic tumours preceding the formation of reticulin and collagen fibres. The expression of fibronectin on cell surfaces as well as in intercellular matrix may be closely related to the organization of the growth patterns of fibrohistiocytic tumours.

Fibronectins↗
PubMed1987

Immunohistochemical demonstration of glial fibrillary acidic protein (GFAP) in nasal gliomas.

Using the Sternberger method (Immunoluk Histoset KIT) GFAP (glial fibrillary acidic protein) was demonstrated immunohistochemically in 4 nasal gliomas. In these histologically complex tumour-like lesions mesenchymal, epithelial, and neuroglial tissues as well as small groups of scattered glial elements could be differentiated specifically by the highly sensitive GFAP immunoperoxidase technique. GFAP was present in astrocytes and astrocyte-like differentiations. The reactivity of cell processes was essentially lower. The GFAP immunostain does not always correlate with Mallory's phosphotungstic acid hematoxylin (PTAH) stain and Gallyas' silver impregnation method for astrocytes. Additionally the immunohistochemical investigation of semithin sections prepared by the so-called pop off technique after Bretschneider et al. (1981) allows the correct localization of GFAP in astrocytes and their modulations. Furthermore, in this study, the intimate connection of epithelium and glial cells as well as astrocytes containing hemosiderin granules could be demonstrated. The latter findings suggest a possible phagocytotic activity of astrocytes. Our results show that the demonstration of GFAP by the Sternberger method is a valuable aid in establishing astrocytic glial differentiations and modulations in complex tumour-like lesions such as nasal gliomas.

Glial Fibrillary Acidic Protein↗
PubMed1987

[Results of treatment following stage-dependent therapy of non-seminomatous testicular tumors].

The results of the treatment of 194 patients with non-seminomas were analyzed and statistically registered. The therapeutic approach is described and the cumulative probability of survival is compared according to the stages. For the total number of these tumours a cumulative 5-year-survival probability of 68.6% was calculated. In detail it reaches from 100% in clinical stage I to 39.7% in clinical stage III. The decisive change of the prognosis is between the clinical stages IIb and IIc. An adjuvant cytostatic therapy should, if performed, be aggressive. Relapses in the clinical stage I are possible and call for a critical valuation of the primary stage. A retarded cytostatic polychemotherapy should be performed only under certain conditions.

Antineoplastic Combined Chemotherapy Protocols↗