Proteoglycans in the notochord sheath of lampreys.

The distribution of proteoglycans in the sheath and epithelial cells of the lamprey notochord had been studied using electron microscopy on material stained with the dye cupromeronic blue (CMB). CMB-precipitates, which indicate the presence of sulphated proteoglycans, were found in the inner collagenous but not the outer "elastica externa" regions of the notochord sheath. Precipitates were also found in the zone of the basement membrane of the notochord epithelial cells, in intercellular spaces within the notochord epithelium, and in intracellular spherical bodies of the epithelial cells. These results indicate that the proteoglycans in the notochord sheath are produced by the notochord cells. The combined presence of sulphated proteoglycans and collagen type II in the notochord sheath parallels the situation found in the cartilage of higher vertebrates.

[Liability of the consulting physician]. / Die Haftung des Konsiliararztes.

Problems of the malpractice law in telemedicine was hardly discussed until now. The consulting doctor in the centre is consulted by a "primary treating physician" to take part in treating the patient directly or indirectly. In the doctor's establishment, the consulting doctor is usually not the assistant of the "primary treating physician" and is therefore not legally responsible by contract. In hospital, the legal responsibility depends on the hospital contract-whether it is total or split. In the case of a total contract, all doctors involved in treating the patient are assistants of the hospital. In the case of a split contract, the consulting doctor has his own contract with the patient. With this premise the consulting doctor is also legally responsible for damage through a third party. In the field of communication and organization mistakes, all doctors that are involved might be legally responsible. From the view of the criminal law, the responsibility of the consulting doctor is considered regarding physical injury resulting from negligence, manslaughter through culpable negligence and denial of assistance. As the boundaries for the duty of assistance are not locally restricted but drawn with the criteria of reasonableness, telemedicine would lead to an enormous extension of the people who have the duty to help.

Glycosaminoglycans in porcine lung: an ultrastructural study using cupromeronic blue.

Glycosaminoglycans (GAGs) are essential components of the extracellular matrix contributing to the mechanical properties of connective tissues as well as to cell recognition and growth regulation. The ultrastructural localization of GAGs in porcine lung was studied by means of the dye Cupromeronic Blue in the presence of 0.3 M MgCl2 according to Scott's critical electrolyte concentration technique. GAGs were observed in locations described as follows. Pleura: Dermatan sulphate (DS) and chondroitin sulphate (CS) attached in the region of the d-band of collagen fibrils, interconnecting the fibrils; heparan sulphate (HS) at the surface of elastic fibers and in the basement membrane of the mesothelium and blood vessels. Bronchial cartilage: Abundant amounts of GAGs were observed in three zones: pericellular, in the intercellular matrix and at the perichondrial collagen. By enzyme digestion a superficial cartilage layer with predominantly CS could be distinguished from a deep zone with CS and keratan sulphate. The structure of the large aggregating cartilage proteoglycan was confirmed in situ. Airway epithelium: HS at the whole surface of cilia and microvilli and in the basement membrane of the epithelial cells. Alveolar wall: CS/DS at collagen fibrils, HS at the surface of elastic fibers and in the basement membranes of epithelium and endothelium.

Ultrastructural localization of glycosaminoglycans in the human mammary gland.

The distribution of glycosaminoglycans (GAGs) in the human breast tissue has been studied at the EM-level by means of the dye Cupromeronic Blue and Scott's critical electrolyte concentration technique. There have been several reproducable localizations: 1. Orthogonally at the main bands of collagen fibrils (probably chondroitin/dermatan sulphate). 2. Large GAGs in areas, almost free of collagen and other fibrils (probably chondroitin sulphate). 3. In the basement membranes of capillaries and glandular epithelium (probably heparan sulphate). 4. Fine GAGs at the surface of the adipocytes (probably heparan sulphate). 5. In the heterogenous granules of mast cells (probably heparin).

Glycosaminoglycans and fibrillar collagen in Priapulida: a histo- and cytochemical study.

The distribution of glycosaminoglycans and fibrillar collagen was studied in various tissues of priapulids, which represent an ancient group of marine metazoa. Sulphated glycosaminoglycans, as demonstrated at the electron microscopical level by Cupromeronic blue, were predominantly found in the cuticle, in basement membranes and also in the narrow connective tissue space below epidermis and anterior intestine. On the basis of their morphology the Cupromeronic blue precipitates could be divided into several groups. Fibrillar collagen occurred in the connective tissue under the epidermis and the epithelium of the anterior intestine. The spatial interrelationship between fibrillar collagen and glycosaminoglycans lacked with some exceptions, the high regularity found in connective tissues of other invertebrates and of vertebrates. This might be related to the special skeletal system of priapulids, consisting mainly of a strong extracellular cuticle and the turgor of the fluid-filled body cavity. In such a system the usual supportive structures seem to be of less functional significance.

Tertiary structure and function of closed-circular mitochondrial DNA and its transcription in vivo.

The conformation of the closed circular mitochondrial DNA in cultured human cells is changed by the addition of berenil to the culture medium in such a way that the 34-S mitochondrial DNA is converted into a 29-S DNA and finally into a 24-S DNA. The superhelix density of the covalently closed 29-S mitochondrial DNA is sigma O = -1.5 times 10(-2) (turns/10 base pairs) and consequently is intermediate between the superhelix density of the 34-S DNA (sigma0 = -2.8 times 10(-2)) and that of the closed circular 24-S DNA (sigmao appromiately 0). Removal of the drug reverses the transition, covalently closed circular 34-S DNA to covalently closed circular 29-S DNA to covalently closed circular 24-S DNA. The covalently closed circular 24-S mitochondrial DNA is not replicated. Transcription of this DNA is also inhibited as indicated by the fact that no synthesis of the mitochondrial ribosomal RNAs occurs as long as the mitochondrial DNA is in this conformation. The covalently closed circular 29-S mitochondrial DNA is replicated but not transcribed in vivo.

Ultrastructural localization of glycosaminoglycans in human gingival connective tissue using cupromeronic blue.

Human gingiva was stained with cupromeronic blue according to Scott's critical electrolyte concentration technique in order to localize glycosaminoglycans (GAG) in the electron microscope. Identification was performed by digestion with chondroitinase AC, ABC and heparinase. The GAG were localized in three compartments of the connective tissue: the supra-alveolar fiber apparatus, the loose connective tissue and the basement membranes. In the supra-alveolar fiber apparatus, consisting mainly of densely packed parallel collagen fibrils, dermatan sulfate GAG are regularly attached to the d-band of the collagen fibrils. The precipitates (6-7 nm in diameter) aggregate to thicker precipitates (up to 16 nm), thus possibly providing stability to the fiber system. In the loose connective tissue with sparse collagen fibrils dermatan and chondroitin sulfate GAG form very large precipitates (up to 30 nm in diameter and 400 nm length) which interconnect the few collagen fibrils. The basement membranes of the epithelium and capillary endothelium contain heparan sulfate GAG as fine precipitates (4-6 nm in diameter) which form a meshwork. These findings are consistent with the Scott model (1) for the interactions among glycans and glycans and collagen fibrils in connective tissues.

Ultrastructural and biochemical observations on proteoglycans and collagen in the mutable connective tissue of the feather star Antedon bifida (Echinodermata, Crinoidea).

Mutable connective tissue, unique to echinoderms, changes its mechanical behaviour within seconds of nervous stimulation. The molecular mechanism of this phenomenon is not understood. In this study proteoglycans and collagen of the brachial ligaments connecting neighbouring ossicles of the arms of the feather star Antedon bifida have been investigated by biochemistry, light and electron microscopy and the critical electrolyte concentration (CEC) technique using the dye Cupromeronic Blue (CB). The ligaments consist mainly of parallel cross-striated collagen fibrils, 82 +/- 12 nm in diameter, with a characteristic banding pattern and a D-period of 52.8 +/- 3.2 nm. Some fibrils were disaggregated into bundles of 10-11 nm protofibrils, lying between the normal fibrils. Proteoglycans occur at the surface of the fibrils with 2 binding sites (each with a different CEC) per D-period and also inside the fibrils. The surface proteoglycans are more highly sulphated (i.e. their CECs are > 1.3 M) than the intrafibrillar proteoglycans (CEC < 0.9 M). The glycosaminoglycans consist of a highly sulphated chondroitin sulphate, possibly with fucose residues. The results are consistent with the theory that disaggregation of the fibrils into protofibrils and reaggregation might be a mechanism of mutability, without excluding the possibility that fibrils may slide alongside each other during movements in the viscous phase of the ligament.

Relapsing poly(peri)chondritis associated with fibrosing alveolar disease and antibodies to pneumocytes type II and Clara cells.

A 62-year-old man with histological confirmed relapsing polychondritis showed chondritis of ears and nose, arthritis, keratitis and a hemolytic anemia. The bronchoalveolar lavage, computed tomography of the thorax and pulmonary function tests disclosed findings compatible with fibrosing alveolar disease. IgG antibodies to alveolar pneumocytes type II and bronchiolar Clara cells were detected by indirect immunofluorescence of human lung tissue. To our knowledge this is the first report of fibrosing alveolar disease in relapsing polychondritis and detection of antibodies to human pneumocytes type II and Clara cells.

Similar frequency of autoantibodies against pneumocytes type II and Clara cells in patients with interstitial lung diseases and healthy persons.

Several experimental findings suggest an association between interstitial lung diseases and autoantibodies. Antibodies against lung tissue including pneumocytes type II in patients suffering from idiopathic pulmonary fibrosis (IPF) were reported in recent years. In this investigation the serum of 103 persons (10 with IPF, 23 with M. Boeck, 18 with rheumatoid arthritis (RA) and 52 healthy controls) was examined for autoantibodies against pneumocytes type II and Clara cells by indirect immunofluorescence on human lung tissue. These antibodies against both cell types are an additional proof for common antigens in pneumocytes type II and Clara cells. The autoantibodies were present in similar frequency in the 4 groups (IPF: 20%, M. Boeck: 26.1%, RA: 22.2% and 23.1% of the healthy controls). So no significant association was found between the antibodies and the interstitial lung diseases. A role of the antibodies in the pathogenesis of the diseases, however, can not be excluded by this study. A possible role as parameter of development of interstitial lung diseases should be subject to further investigations in form of a prospective follow up study.