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Biomedical subjects

G Seifert

Publications and source records attributed to G Seifert.

At least 181 records · Page 10Linked to original sources
PubMed1977

The coxal glands of geophilomorpha (chilopoda): organs of osmoregulation.

The organs terminating at the coxal pores of the tug-legs of Geophilomorpha are not repugnatorial glands, but possess typical transport epithelia with deep apical and basal infolding of the cell membranes, between which numerous large mitochondria are located. Many transport vesicles are found in the basal region but fewer in the apical cytoplasm. The apex is characterized by bundles of longitudinally oriented microtubules, sparse endoplasmic reticulum and free ribosomes. Single neurosecretory axons with synaptoid areas are scattered among the cells. It is suggested that the coxal organs have a diuretic function in moist habitats and an antidiuretic effect in arid environments. The "switch-over" is evidently controlled by a neuroendocrine mechanism.

Animals↗
PubMed1977

Advances in the morphological diagnosis of bone tumours: cytology, cytochemistry, acrylate embedding and electron microscopy (author's transl).

An exact morphological diagnosis of bone tumours is the prerequisite for selective treatment. In a given case this may present great difficulties, partly because of the rarity of a tumour group and thus lack of experience, partly faulty removal of the specimen and unsatisfactory further technical handling. Progress can be expected only by widening the spectrum of methods by using modern morphological tests. In a programme using imprint cytology, cytochemistry, rapid section, histochemistry, paraffin, non-decalcified embedding in acrylate and electron microscopy it was demonstrated in 78 cases of bone tumour (seen over a period of two years) that with these tests, especially cytology, cytochemistry and non-decalcified acrylate histology, significant improvement can be obtained in the morphological diagnosis of bone tumours. In addition, new lights on cytogenesis and pathogenesis of these tumours and possible points of attack of cytostatic treatment are provided.

Adolescent↗
PubMed1977

Histopathological features in mixed types of chronic aggressive hepatitis and primary biliary cirrhosis. Correlations of liver histology with mitochondrial antibodies of different specificity.

A histopathological study was carried out on 27 patients with chronic inflammatory liver disease and clinical and/or biochemical evidence of cholestasis who had either mitochondrial antibodies against mitochondrial antigen fractions of 1.19 density ("PBC antigen"; 14 cases) or of 1.13 density ("CAH-PBC mixed-type antigen"; 13 cases). For comparison, the liver biopsies of 17 patients with chronic-aggressive hepatitis (CAH) and antinuclear and/or anti-smooth muscle antibodies but without cholestasis and mitochondrial antibodies, were evaluated. The 14 patients with mitochondrial antibodies against the PBC antigen showed the typical histological features of primary biliary cirrhosis (PBC). The 13 patients with mitochondrial antibodies against the CAH-PBC mixed-type antigen had heterogenous liver alterations. In 11 cases highly active CAH and/or active postnecrotic cirrhosis (AC) were found both with augmented ductular proliferation. Some of these cases showed distinct criteria of PBC as early bile duct lesions or absence of regular bile ducts. The liver histology of one case corresponded to classical PBC; another case to chronic persistent hepatitis. The CAH-patients without cholestasis and mitochondrial antibodies only occasionally showed bile duct proliferation. In conclusion, a high correlation was found between mitochondrial antibodies against the CAH-PBC mixed-type antigen and highly active CAH or early AC with augmented ductular proliferation. This represents an overlapping of CAH and PBC. In contrast, the cases with antibodies reacting to the PBC antigen showed the slowly progressive liver changes of typical PBC.

Antibodies↗
PubMed1977

[Morphological classification of oral leukoplakia (author's transl)].

656 cases of oral leukoplakia were analysed according to macroscopic aspects, microscopic growth patterns and histologicalcytological differentiation, and the relationship to cancer of the oral cavity was studied. Homogeneous and speckled leukoplakia can be distinguished macroscopically, while flat (70%), papillary-endophytic (22%) and papillomatous-exophytic (8%) types can be distinguished by their growth pattern. Histological-cytological characteristics consist of epithelial hyperplasia (hyperkeratosis with ortho- or parakeratosis; akanthosis) and epithelial dysplasia (dyskeratosis, basal-cell hyperplasia, loss of polar arrangement of the basal cells, cell polymorphism, increased mitosis rate). No or little dysplasia was demonstrated in 74% of leukoplakias, moderate in 17% and marked in 6%. Carcinoma-in-situ, defined as high-grade dysplasia with additional loss of epithelial layering, was found in 3%. Precancerous leukoplakia (in almost 10% of cases, counting high-grade dysplasias and carcinoma-in-situ) must be delineated as a special group. Numerous correlations were found between dysplastic leukoplakias and oral cavity cancer as regards localisation, age and sex distribution. In the various leukoplakia forms there was an increased incidence of marked stroma reactions and of Candida colonisation with increased degrees of dysplasia.

Adolescent↗
PubMed1977

[Carcinomas in papillary cystadenolymphomas of the parotid gland--definition and differential diagnosis (author's transl)].

Within a collective of 1431 salivavry gland tumors of the salivary gland register (1965--1976) an observation has been done, which has been classified as a "carcinoma in a papillary cystadenolymphoma". Corresponding to the "carcinoma in a pleomorphous adenoma" of the WHO-classification of salivary gland tumors the terminus "carcinoma in a cystadenolymphoma" is further defined. 6 additional cases from the literature are reviewed. The possible role of epithelial metaplasia and of a proceding radiation in the development of carcinomas in cystadenolymphomas are discussed. The following other tumors have to be differentiated from a carcinoma in a cystadenolymphoma: Metastases of other tumors beyond a cystadenolymphoma; malignant lymphoepithelial lesions (predominantly malignant lymphomas in a preexisting immune-sialadenitis of the myoepithelial sialadenitis type; rare carcinomas), and lymphoepitheliomas.

Adenocarcinoma↗
PubMed1977

[Hematogenous metastases of benign pleomorphic adenomas of the salivary glands (author's transl)].

Hematogenous metastases of benign pleomorphic adenomas are exceptionally rare. In three secure reports of the world literature metastases occurred in lung, liver or bone after operation of a benign pleomorphic adenoma with the greatest interval of twenty-two years between operation and metastases. This will be interpreted as implantation-metastases. All other observations represented secondary carcinomas in pre-existing pleomorphic adenomas. The morphological criterias of an accurate classification are explained. A number of reports of the literature about metastases of benign pleomorphic adenomas deals with misinterpretations of secondary adenomas in pre-existing pleomorphic adenomas.

Adenoma↗
PubMed1977

[Granular cell tumour of the parotid gland. The differential diagnostic criteria (author's transl)].

Granular cell tumours (synonyms: myoblastmyomas, granular neuromas, granular cell myoblastomas) are localized predominantly in the head and neck area, especially in the region of tongue and larynx. Only 2 observations of an occurrence in the parotid gland exist till now in the world literature. This paper reports a further case of an occurrence in the parotid gland in a 6-years-old girl. The about cherrygreat tumour was distinctly limited and showed histologically a typic lobular arrangement of acidophilic granular cells. No recidive was observed in the prevailing postoperative phase of 3 years. The differential diagnosis of the granular cell tumorus is demonstrated to other tumour types with similar histological arrangement, expecially to the alveolar soft-part sarcoma, the acinic cell tumour and the non-chrom-affine paraganglioma (chemodectoma).

Adult↗
PubMed1977

[Fibrosing alveolitis--a contribution to the ultrastructure and pathogenesis of interstitial pulmonary diseases (author's transl)].

Considering the functional anatomy of the lung parenchyma the pathomorphological response pattern of the alveolus has been described. Hereby, the fibrosing alveolitis is conceived as an uniform concept of a disease, to which many different aetiological factors are associated. The ultrastructural pathology of early changes in fibrosing alveolitis has been described in the bleomycin lung as an example, which pathogenesis (as a chemically induced pulmonary damage) has a character of a model for the process of fibrosing alveolitis.

Alveolitis, Extrinsic Allergic↗
PubMed1977

[On the pathogenesis of the Küttner tumor of the submandibular gland -- Analysis of 349 cases with chronic sialadenitis of the submandibular (author's transl)].

In view of the etiology and pathogenesis of the so-called Kütter tumor (chronic sialadenitis of the submandibular gland) gland resections of 349 patients (salivary gland register at the Institute of Pathology, University of Hamburg; period 165--1974) were analyzed pathohistologically. In 143 cases (41%) a sialolithiasis of the submandibular gland occurred simultaneously. Regarding the degree of the inflammation 4 stages were distinguished (stage 1 = focal sialadenitis; stage 2= diffuse lymphocytic sialadenitis with salivary gland fibrosis; stage 3 = chronic sclerosing sialadenitis with salivary gland sclerosis; stage 4= chronic progressive sialadenitis with salivary gland cirrhosis). Twenty-five per cent of the cases were classified in stage 1, 19% in stage 2, 38% in stage 3, and 18% in stage 4. A predominance of the male sex (70%) was observed especially in stage 4. The initial stage is characterized by a periductally lymphocytic infiltration, ectasias of the ducts, and alteration of the secret in the duct lumens (spheroliths, microliths). In stages 2--3 an increase of the inflammatory infiltration with lymph follicles, considerable alterations of the ducts (metaplasias, dysplasias, regenerates of the ducts), and a parenchymal reduction were found. This process is combined with an increase of the interstitial connective tissue and a cicatrication of the salivary gland parenchyma. In the final stage, 4, a cirrhotic gland transformation with progressive loss of the parenchyma and considerable duct destruction appeared. From the pathogenetic course of the inflammation and the comparison with other forms of sialadenitis, the conclusion is drawn that two etiologic factors are important in the Küttner tumor: an initial disturbance of secretion with an obstructive electrolyte sialadenitis and an immune reaction of the salivary duct system with the final phase of an obstructive, progressive immunosialadenitis.

Adolescent↗
PubMed1976

[Morphology of salivary gland diseases].

The human salivary glands represent a functional system with manifold responsibilities and interactions to the organism. The major and minor salivary glands show a common construction schedule consisting of an acinar functional system for the production of an enzyme- and mucin-containing primary saliva and a ductal functional system with manifold secretory, resorptive and regulatory responsibilities for the transport and the definitive composition of the saliva. The cyclic AMP and calcium iones localized in the glandular acini have an exceptional importance for the course of the secretory process. The neurohormonal control of the salivary secretion results by adrenergic and cholinergic transmitter substances. Moreover the secretory process shows a daily cycle combined with morphological alterations of the glandular cells (so called circadian structures). The fluid secretion of the salivary duct system (the output of sodium-, potassium- and chlorine-iones) represents an active energy-consumed transport process which will be regulated by several factors (autonomic nervous system, quantity of perfusion, hydrostatic pressure in the blood capillaries, transepithelial active transport by ATP-consumed pump systems). The striated ducts are the functional most important sector of the duct system for a rapid fluid- and electrolyte excretion. The terminal axons of the postganglionic sympathic and parasympathic neurits are characterized by spindle-shaped enlargements (varicosities) which contain neurosecretory granules. In the region of the acinar and intercalated duct cells a direct synaptic contact exists for the stimulation transmission, in the course of which the terminal axon contacts immediately with the effector cell by penetration of the basement membrane. The salivary glands form a part of the stabil tissues with reversible postmitotic cells in regard of the tissue regeneration. Under pathological conditions (inflammations, impediment of secretion fluid, radiation effects etc.) metaplasias and proliferations of the duct system arise with development of indifferent duct formations analogous to the type of an embryonal salivary gland. The terminal zone between intercalated and striated ducts represents an indifferent zone with large regeneratory potency. A special behaviour shows the myoepithelial cells which are developed as well to the outside of primitive embryonic duct buds as differentiated intercalated and striated ducts. Morphologically three types of diseases can be classified in the salivary glands: sialadenosis, sialadenitis and tumours.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗
PubMed1976

Classification of the pathohistology of diseases of the salivary glands - review of 2,600 cases in the Salivary Gland Register.

Three major disease groups emerge from a classification of the pathohistology of 2,600 salivary gland preparations in the salivary gland register (from 1965 to 1974): salivary gland tumors (41%), salivary gland inflammations (26%), and sialadenosis (6%). Mucoceles (2%) and salivary gland cysts (1.5%) are seen less often. It is diagnostically important that lymph node changes in the area of the salivary glands (lymphadenitis, lymphomas, etc.) are worked up under suspicion of a primary salivary gland disease. Sialadenosis involves a primary, vegetative neuropathy, which is accompanied by enlargement of acinar cells. Under the heading of chronic sialdenitis, we fine 50% socalled Küttner tumors of the submandibular gland, 21% chronic relapsing parotitis, 14% chronic inflammations of the minor salivary glands and the sublingual gland, and 12% immune sialadenitis (myoepithelial sialadenitis in Sjögren's syndrome and epitheloid cell sialadenitis in Heerfordts syndrome). A more than average number of immune sialadenitis cases develop into malignant lymphomas (4 cases in the salivary gland register). The 1,067 tumor cases containing of 929 epithelial tumors (87%), 89 mesenchymal tumors (hemangiomas, lymphangiomas, lipomas, neurofibromas, sarcomas) and 49 metastases or periglandular tumors. Epithelial tumors were grouped on the basis of the World Health Organization (WHO) classification. Benign tumors (71.5%) consisted of pleomorphic adenomas (51.5%) and monomorphic adenomas (50%). After the pleomorphic adenomas, cystadenolymphomas (over 10%) represented the most frequent benign salivary gland tumor. On the basis of epithelial and stromal differentiation, pleomorphic adenomas were subdividied into four subtypes (stroma-rich and stroma-poor adenomas). The malignant tumors consisted of acinar cell tumors (2.5%), mucoepidermoid tumors (6%), and carcinomas at various levels of differentiation (adenoid-cystic carcinomas, 6.5%; adenocarcinomas, 2%; squamous cell carcinomas, 2%; carcinomas in pleomorphic adenomas, 4%; miscellaneous carcinomas - salivary duct carcinomas, clear-cell carcinomas, undifferentiated carcinomas, 5.5%). Differences in age and sex distribution, localization, malignity metastases, recidivism, et

Adenoma↗
PubMed1976

[A pathological classification of pleomorphic adenoma of the salivary glands (author's transl)].

Pleomorphic adenomas of the salivary glands show, despite their pleomorphism, certain histological characteristics. These are based onthe differentiation of the epithelial cell and the amount and nature of the stroma. A systematic histological analysis of 310 pleomorphic adenomas of the parotid gland resulted in the following findings and classification. 1. The most frequent epithelial cell forms were salivary duct and myoepithelial cells (75-90%) seen as epidermoid cell groups (75%). Rarer forms of differentiation were striated duct cells (5%), keratinised squamous epithelium (2,5%), oncocytes (1%), basal cells (1%), and sebaceous gland cells or goblet cells (less than 1%). 2. A myxomatous stroma represented the prototype of stromal differentiation (80%). A chondroid stroma was found in 10% of cases examined and a mixed mucochondroid stroma in 3%. Further differentiation included hyaline stroma (25%) and fibrous stroma (15%) especially in the older tumour or after irradiation. Rarely was a fascicular (0,5%) or osseous (1%) stromal change found. 3. Four subgroups of pleomorphic adenoma can be classified from consideration of the epithelial and stromal changes. Subgroup 1 (30,5%) is the classical pleomorphic adenoma with a stroma content of 30-50%; subgroup 2 (55%) has a stroma content of 80%; subgroup 3 (9%) has a poor stroma content of 20-30% or less and an epitaelial differentiation similar to subgroup 1; and subgroup 4 has also a poor stroma content (6%) with a relatively monomorphic epithelial structure. 4. Recurrences (13,5%) were seen more in stroma-rich pleomorphic adenomas than in stroma-poor tumours. 5. On the basis of cytological differentiation, pleomorphic adenomas develop from indifferent tissue adjacent to salivary intercalated or striated ducts.

Adenoma↗
PubMed1976

[Recent progress in morphology and diagnosis of bone diseases and bone tumors (author's transl)].

1. Bone structure is shaped by a specialized bone cell system comprising osteoblasts, osteocytes and osteoclasts. --2. The function of this bone cell system is impaired by metabolic bone disease altering bone structure, bone mass and mineral content. --3. In metabolic bone disease a striking improvement in morphologic diagnosis could be obtained recently using undecalcified preparations of bone tissue as well as histomorphometric methods. --4. For exact diagnosis and successful therapy of bone tumors interdisciplinary cooperation is mandatory. The advantages of modern morphologic methods are proven helpful in diagnosing benign and malignant bone tumors.

Age Factors↗
PubMed1976

[Malignant lymphomas and immunosialadenitis (author's transl].

Immune sialadenitis with or without clinical symptoms of Sjögren's syndrome represents an inflammation of the salivary duct system with considerable proliferation of the immunoactive lymphoproliferative system. By prolonged stimulation the immune system can turn into malignant lymphoma, mainly of immunocytoma or immunoblastic sarcoma type. In four out of 77 cases from the salivary gland register of the Institute of Pathology, University of Hamburg, showing myoepithelial sialadenitis, malignant lymphomas associated with chronic myoepithelial lymphadenitis were observed. According to the new "Kiel-classification" (Lennert) of malignant lymphomas two of the cases represented a diffuse germinoblastoma (lymphoblastoma Brill-Symmers), one a immunocytic lymphoma and one a immunoblastic sarcoma (reticulum cell sarcoma). From literature 16 further observations of malignant lymphoma occuring in the area of the major salivary glands in association with immune sialadenitis (Sjögren's syndrome) were collected, likewise 25 other cases with lymphomas outside of the major salivary glands and Sjögren's syndrome. It is suggested that the above average frequency of malignant lymphomas in immune sialadenitis may result from a secondary malignant transformation of immune cells due to prolonged stimulation. Local rapidly appearing tumorous alterations of the salivary glands in chronic immune sialadenitis are, therefore, always be suspicious of the development of a malignant lymphoma and demand adequate therapy.

Adult↗