Über bau und funktion der prosoma-drüsen von spinnmilben (Tetranychidae,Trombidiformes)

Zoomorphology - Die licht- und elektronenmikroskopische Untersuchung der Prosomadrüsen der Spinnmilben Bryobia praetiosa, Bryobia rubrioculus und Tetranychus urticae (Tetranychidae,...     

Über Aufbau und Innervation der Kopfanhänge der prosobranchen Schnecken

Zusammenfassung Das Epithel der Kopfanhänge von elf marinen und Süßwasserprosobranchiern besteht aus prismatischen bis kubischen Stützzellen mit meist dichtem Mikrovillussaum und z.T. Pigmentgranula sowie Sinneszellen, die fast immer in Form sekundärer Sinneszellen vorliegen; nur bei Patella coerulea kommen vermutlich auch primäre Sinneszellen vor. Ihr Zytoplasma ist apikal durch glattwandige E. R.-Zisternen, helle Bläschen und Mikrotubuli gekennzeichnet. Außerdem tragen diese Zellen Zilien und stehen basal mit Nervenendigungen in Kontakt, die sich in drei Gruppen einteilen lassen: 1. Vermutlich cholinerge Endigungen mit optisch leeren Bläschen (Ø 600–800 Å). 2. Endigungen mit dense core vesicles (Ø 1000–1100 Å). Die Annahme, daß diese Endigungen biogene Amine enthalten, wird durch fluoreszenzmikroskopische Befunde gestützt. 3. Endigungen mit großen (Ø 3000–4000 Å) neurosekretorischen Elementargranula.

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Structure and innervation of the cephalic tentacles of Prosobranch molluscs

Summary The epithelium of the cephalic tentacles of eleven marine and freshwater prosobranch snails consists of villus bearing supporting cells, which partly contain pigment granules, and sensory cells, which occur in form of secondary sensory cells with the exception of Patella coerulea which presumably possesses primary sensory cells. These receptor cells are characterized as chemoreceptors by apical cilia, smooth surfaced E.R., microtubulues and empty vesicles. At their bases they are in close contact with nerve endings which can be classified in three groups: 1. presumably cholinergic endings with clear vesicles (Ø 600–800 Å). 2. endings with dense core vesicles (Ø 1000–1100 Å). The assumption that these endings contain biogenic amines is supported by positive fluorescence microscopical tests. 3. Endings with big (Ø 3000–4000 Å) neurosecretory elementary granules.

Herrn Prof. Dr. W. Bargmann danke ich für die Überlassung eines Arbeitsplatzes im Anatomischen Institut Kiel.     

Comparative Study of Cultured Burkitt Tumor Cells by Immunofluorescence, Autoradiography, and Electron Microscopy

Cultured Burkitt cells were examined by immunofluorescence, autoradiography, and electron microscopy in an effort to identify the stainable cells with those harboring herpes-type virus particles. Immediately after a 2-hr pulse of (3)H-thymidine, from 30 to 60% of the cells revealed heavy nuclear labeling. In most cases the grains were evenly dispersed, but in about 3 to 5% the grains showed a focal distribution and occasionally they extended into the cytoplasm. Such nuclear foci were rarely seen at 8 hr after the pulse. When the analysis was restricted to preselected immunofluorescent cells, up to 80% showed label at 8 hr and cytoplasmic grains were prominent. To reduce cellular deoxyribonucleic acid (DNA) synthesis, cells were X-irradiated with 3,000 to 6,000 R, and the isotope pulse was applied 1, 4, or 7 days later. Whereas the total number of labeled cells decreased in roughly twofold steps at the respective intervals (from 40 to 10%), the incorporation of (3)H-thymidine into fluorescent cells was not affected by X irradiation. In each series, about 70% of the fluorescent cells contained label when they were examined at 24 and 48 hr after the pulse, whereas at 8 and 72 hr fewer were positive. At the earlier intervals, unlabeled fluorescent cells most likely represented cells which had completed viral DNA synthesis prior to the pulse; at the later intervals, unlabeled fluorescent cells were probably cells which commenced viral replication after the pulse. These data support the conclusion that the immunofluorescent cells are the ones which harbor virus, and also confirm the expectation that the virus is a DNA virus from a member of the herpes group. This conclusion was firmly established by sectioning and electron microscopic examination of individual fluorescent cells, all of which contained numerous virus particles, whereas the nonstained cells prepared in a similar manner were free of them.