How many Layers has the Adventitia? - Structure of the Arterial Tunica Externa Revisited.

Tunica adventitia or tunica externa is the outer layer of the blood vessel wall. It consists of connective tissue with vasa and nervi vasorum and plays a key role in vascular health. The aim of our study was to compare the wall layers beyond tunica media in arteries of different type and location. The following arteries of pig, dog and cat were processed histologically and analysed by light microscopy: aorta ascendens, arcus aortae, aorta thoracica, aorta abdominalis, arteria (a.) femoralis, a. tibialis cranialis, a. carotis communis, a. lingualis, a. basilaris, a. cerebralis media, a. testicularis and aa. jejunales. We found two layers of connective tissue outside the media: (1) a compact layer with many elastic fibres in muscular and few in elastic arteries and (2) an outer layer of loose connective tissue. The compact layer was missing in aorta ascendens, arcus aortae and intracranial vessels. Adventitial stripping removed only the loose connective tissue layer. In spite of the still present compact layer, stripped arteries were very flimsy. We suggest using the term 'tunica externa' for the compact connective tissue layer and 'tunica adventitia' for the outermost loose connective tissue layer as in other organs. The presence of the tunica externa differs between species, arteries and arterial side, as well as the removability of tunica adventitia and tunica externa by anatomical dissection.

[Primary cutaneous and metastasing haemangiosarcoma in an addax (Addax nasomaculatus)]. / Primäres, kutanes, metastasierendes Hämangiosarkom bei einer Mendesantilope (Addax nasomaculatus).

Neoplastic diseases were described very rarely in addax (Addax nasomaculatus). In this communication clinical signs, morphological and immunohistological findings in a 15-year-old, female addax with a primary cutaneous, re-occurring and metastasing haemangiosarcoma of a forelimb are reported.

Autoantibodies to tissue transglutaminase as predictors of celiac disease.

BACKGROUND & AIMS: Immunoglobulin A (IgA) autoantibodies to endomysium (EMA) are highly specific and sensitive markers for celiac disease. Recently, we identified tissue transglutaminase (tTG) as the major if not sole endomysial autoantigen. METHODS: An enzyme-linked immunosorbent assay (ELISA) was established to measure IgA anti-tTG titers in serum samples from 106 celiac patients with partial or subtotal villous atrophy, 43 celiac patients on a gluten-free diet, and 114 diseased and healthy controls. Results were correlated with clinical and histological data and with EMA titers. RESULTS: In patients with biopsy-proven celiac disease consuming a normal, gluten-containing diet, 98.1% of the serum samples had elevated IgA titers against tTG, whereas 94.7% of the control sera were negative. IgA anti-tTG correlated positively with semiquantitative IgA EMA titers (r = 0.862; P < 0.0001). CONCLUSIONS: An ELISA based on tTG allows diagnosis of celiac disease with a high sensitivity and specificity. IgA anti-tTG and IgA EMA show an excellent correlation, further confirming the enzyme as the celiac disease autoantigen. Because the assay is quantitative, not subjected to interobserver variation, and easy to perform, it will be a useful tool for population screening of a hitherto underdiagnosed disease.

Opposite cardiac actions of the enantiomers of Bay K 8644 at different membrane potentials in guinea-pig papillary muscles.

The influence of membrane potential on the effects of the enantiomers and the racemate of Bay K 8644 [1,4-dihydro-2,6-dimethyl-3-nitro-4-(2-trifluor-methylphenyl)-p yri dine-5-carboxylate] on force of contraction and on action potentials were studied in guinea-pig papillary muscles in order to detect possible changes in the direction of drug action or in potency. Membrane potential was varied by changing the potassium concentration ([K+]o) in the bathing solution. At normal resting potential, (-)-Bay K 8644 enhanced force of contraction and prolonged the action potential duration measured at 50% of repolarization (APD) to the same extent as the racemate and with similar pD2 values. After membrane depolarization by raising [K+]o from 5.4 to 17.4 mmol/l, the (-)-enantiomer and the racemate prolonged the APD to a similar degree but enhanced force to a lesser extent. The maximum rate of depolarization of slow action potentials, Vmax, was increased at the highest concentrations (10(-5) mol/l). The effects of (+)-Bay K 8644 were more complicated. At high concentrations (10(-5) mol/l) it decreased force of contraction and APD, the pD2 values were one order of magnitude lower than for the (-)-enantiomer and the racemate. A high concentration (+)-Bay K 8644 (10(-5) mol/l) virtually abolished contractile activity at all membrane potentials, the extent of shortening in APD increased with membrane depolarization in elevated [K+]o. Vmax of slow action potentials was decreased.(ABSTRACT TRUNCATED AT 250 WORDS)

[Special indication for bundle-nailing of the upper arm (author's transl)]. / Die besondere indikation zur Bündel-Negelung am Oberarm.

From the beginning of 1974 to the end of 1978, 100 fractures of the shaft of the humerus were treated in the Surgical Clinic II of the Darmstadt Municipal Clinics. 50 of these fractures were treated conservatively, whereas 25 were treated osteosynthetically with a broad A.O. plate (A.O. = Arbeitsgemeinschaft für Osteosynthese) or D.C. plate, and 25 by means of intramedullary osteosynthesis with bundle nailing, both these groups achieving stability of movement by this treatment. Attention is drawn to the special indication for bundle nailing when treating fractures of the shaft, with particular emphasis on pathological fractures and spiral shaft fractures, sometimes combined with subcapital humerus fractures in elderly persons. Other conditional indications are fractures of the shaft of the humerus in polytraumatised patients and debris shaft fractures. Of the 25 patients treated by means of bundle nailing, 22 were evaluated roentgenologically, and 17 were followed up. The results are explained, giving a detailed description of the specific surgical technique.