Osteoderm histology of the Pampatheriidae (Cingulata,Xenarthra, Mammalia): Implications for systematics,osteoderm growth,and biomechanical adaptation

Pampatheres are extinct, large‐bodied cingulates, which share morphological characters with both armadillos and glyptodonts but are considered to be more closely related to the latter. The osteoderm histology of six pampathere taxa was examined and compared to the histology of other cingulate osteoderms. This study investigates the development and functional adaptation of pampathere osteoderms as well as the phylogenetic relationships of the Pampatheriidae within the Cingulata. We found that pampathere osteoderms share a uniform histological organization based on a basic diploe‐like structure. After initial stages of intramembranous growth, metaplastic ossification, that is, the direct incorporation and mineralization of pre‐existing protein fibers, plays an important role in osteoderm development and provides information on various kinds of soft tissue otherwise not preserved. The latest stages of osteoderm growth are dominated by periosteal bone formation especially in the superficial cortex. Movable band osteoderms show regular arrangements of incorporated fibers that may increase the resistance of particularly weak areas against strain. The histological composition of pampathere osteoderms is plesiomorphic in its basic structure but shows a number of derived features. A unique array of Sharpey's fibers that are incorporated into the bone matrix at sutured osteoderm margins is interpreted as a synapomorphy of pampatheres. The arrangement of dermal fibers in the deep and superficial cortexes supports the close relationship between pampatheres and glyptodonts. J. Morphol., 2012. © 2011 Wiley Periodicals, Inc.     

cAMP-dependent protein phosphorylation of membrane proteins in the parotid gland, platelets and liver. Comparison of a 22-kDa phosphoprotein from rat parotid microsomes (protein III) with phosphoproteins of similar molecular size from platelet and liver membranes

Stimulation of secretion in exocrine secretory glands leads to the phosphorylation of a 22-kDa membrane protein (protein III) whose function is still unknown [Jahn et al. (1980) Eur. J. Biochem. 112, 345-352; Jahn & S?ling (1980) Proc. Natl Acad. Sci. USA 78, 6903-6906]. This report describes the comparison of this protein with phosphorylated membrane proteins of similar molecular mass in platelets and liver. Incubation of platelets with agents which raise the intracellular cAMP concentration results in the phosphorylation of a 22-kDa protein which is also phosphorylated in membrane preparations by endogenous kinases or by exogenous cAMP-dependent protein kinase. It is shown that this protein is distinct from protein III although both proteins have the same molecular mass and are substrates of cAMP-dependent protein kinase. In contrast to platelets, protein III could be demonstrated in liver microsomes. This indicates that the function of protein III is not exclusively linked to the stimulus-secretion coupling in exocrine cells.     

Development of Eye Position Dependency of Slow Phase Velocity during Caloric Stimulation

The nystagmus in patients with vestibular disorders often has an eye position dependency, called Alexander’s law, where the slow phase velocity is higher with gaze in the fast phase direction compared with gaze in the slow phase direction. Alexander’s law has been hypothesized to arise either due to adaptive changes in the velocity-to-position neural integrator, or as a consequence of processing of the vestibular-ocular reflex. We tested whether Alexander’s law arises only as a consequence of non-physiologic vestibular stimulation. We measured the time course of the development of Alexander’s law in healthy humans with nystagmus caused by three types of caloric vestibular stimulation: cold (unilateral inhibition), warm (unilateral excitation), and simultaneous bilateral bithermal (one side cold, the other warm) stimulation, mimicking the normal push-pull pattern of vestibular stimulation. Alexander’s law, measured as a negative slope of the velocity versus position curve, was observed in all conditions. A reversed pattern of eye position dependency (positive slope) was found <10% of the time. The slope often changed with nystagmus velocity (cross-correlation of nystagmus speed and slope was significant in 50% of cases), and the average lag of the slope with the speed was not significantly different from zero. Our results do not support the hypothesis that Alexander’s law can only be observed with non-physiologic vestibular stimulation. Further, the rapid development of Alexander’s law, while possible for an adaptive mechanism, is nonetheless quite fast compared to most other ocular motor adaptations. These results suggest that Alexander’s law may not be a consequence of a true adaptive mechanism.     

Tauchbeobachtungen an Plankton und an Echostreuschichten

Zusammenfassung 1. Das Tauchen als Methode zur Untersuchung von Plankton und Echostreuschichten wird durch vier Beispiele erläutert: (a) Visuelle Beobachtungen an Wasserschichtungen und Grenzschichten durch Schwimmtaucher. (b) Untersuchung von Echostreuschichten durch Freitaucher, wobei sich ergab, daß angesammeltes biogenes Material in den untersuchten Sprung- beziehungsweise Streuschichten die Schallreflektion nicht beeinflußt. (c) Beobachtung von Großplankton und Feststellung von Planktonund Sestonkonzentrationen beim Tauchen mit dem Bathyscaph. (d) Untersuchung der Tiefenstreuschicht (deep scattering layer) durch Beobachtung der Vertikalwanderung bestimmter Arten des Großplanktons mit den Tauchbooten Bathyscaph und Soucoupe Plongeante. Physonectide Siphonophoren und Myctophiden standen in deutlicher Beziehung zur Tiefenstreuschicht und wurden als Echogeber erkannt.2. Die Möglichkeiten, von Tauchbooten aus quantitative und qualitative Proben von Plankton und auch vom Benthos zu nehmen, sind zur Zeit noch unzureichend. Die Entwicklung entsprechender Geräte für den wahlweisen und mehrfachen Einsatz bei demselben Tauchgang wird empfohlen.

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Diving observations on plankton and on scattering layers

Diving techniques are employed as a research tool in plankton investigations carried out in shallow water of the western Baltic Sea. Observations and samplings were made by skin divers on scattering layers corresponding to the discontinuity layers. Biogene materials, sometimes concentrated at the thermocline, are not responsible for this special kind of scattering, but rather discontinuity of salinity and temperature (Lenz 1965). For observations in deep water the use of undersea vehicles is recommended. From the Bathyscaph and the diving saucer, single plankton organisms and plankton concentrations were observed (e. g.Bernard 1958); investigations on the deep scattering layer have shown physonectid siphonophores and myctophids to be scatterers (Barham 1966). The equipment for sampling plankton and benthos from undersea vehicles is poorly developed. We need urgently gear for quantitative and qualitative sampling and for manifold use during single dives, i. e., multiple sampling gear and magazins for storage of samples.

     

Blastomycosis in wild wolves

Blastomycosis was fatal to a wild wolf in Minnesota, and serologic evidence of blastomycosis was found in a Wisconsin wolf. No unusual movements were detected in the Minnesota animal from October 1983 through October 1985. However, by early December 1985, this wolf was weak and debilitated, and it perished on 14 December after approaching a human residence.     

Comparative yields of T-2 toxin and related trichothecenes from five toxicologically important strains of Fusarium sporotrichioides.

The range and comparative yields of T-2 toxin and related trichothecenes from five toxicologically important strains of Fusarium sporotrichioides, i.e., NRRL 3299, NRRL 3510, M-1-1, HPB 071178-13, and F-38, were determined. Lyophilized cultures of the five strains maintained in the International Toxic Fusarium Reference Collection were used to inoculate autoclaved corn kernels. Corn cultures were incubated at 15 degrees C for 21 days and analyzed for trichothecenes by thin-layer chromatography and capillary gas chromatography. All five strains produced T-2 toxin, HT-2 toxin, T-2 triol, and neosolaniol. Two strains also produced T-2 tetraol, and two others produced diacetoxyscirpenol. The highest producer of T-2 toxin (1,300 mg/kg), HT-2 toxin (200 mg/kg), T-2 triol (1.9 mg/kg), and neosolaniol (170 mg/kg) was NRRL 3510, which was originally isolated from millet associated with outbreaks of alimentary toxic aleukia in the USSR. The second highest producer of T-2 toxin (930 mg/kg) was NRRL 3299. The other three strains produced T-2 toxin at levels ranging from 130 to 660 mg/kg. Thus, the five strains differed considerably in the amounts of T-2 toxin and other trichothecenes produced under identical laboratory conditions. These strains are being maintained under optimal conditions for the preservation of Fusarium cultures and are available from the Fusarium Research Center, The Pennsylvania State University, University Park.     

Metallothionein induction by nonsteroidal antiinflammatory drugs

In the present study we report on the effects of commonly used nonsteroidal antiinflammatory drugs on metallothionein (MT) and MT-I mRNA levels. A single dose of chloroquine (100 mg/kg), diclofenac (100 mg/kg), indomethacin (10 mg/kg), or piroxicam (100 mg/kg) was administered ip to C57B1 mice. After 18 h, MT levels were determined with a Cd-saturation radioassay. MT-I mRNA levels were measured by Northern Blot analyses using a probe containing the mouse MT-I gene. All drugs tested caused an increase in the MT content of the liver but not of the kidneys and lung. The lowest and highest effects were observed with chloroquine (8 times the control value) and diclofenac (18 times), respectively. In accordance with the stimulation of MT synthesis, increased accumulation of hepatic MT-I mRNA could be demonstrated. These results indicate that elevated MT levels may contribute to the effectiveness of nonsteroidal antiinflammatory drugs in the treatment of rheumatoid arthritis (RA).