Multiaxial movements at the minke whale temporomandibular joint

Mandibular mobility accompanying gape change in Northern and Antarctic minke whales was investigated by manipulating jaws of carcasses, recording jaw movements via digital instruments (inclinometers, accelerometers, and goniometers), and examining osteological and soft tissue movements via computed tomography (CT)-scans. We investigated longitudinal (α) rotation of the mandible and mediolateral displacement at the symphysis (Ω₁) and temporomandibular joint (Ω₂) as the mouth opened (Δ). Results indicated three phases of jaw opening. In the first phase, as gape increased from zero to 8°, there was slight (<1°) α and Ω rotation. As gape increased between 20 and 30°, the mandibles rotated slightly laterally (Mean 3°), the posterior condyles were slightly medially displaced (Mean 4°), and the anterior ends at the symphysis were laterally displaced (Mean 3°). In the third phase of jaw opening, from 30° to full (≥90°) gape, these motions reversed: mandibles rotated medially (Mean 29°), condyles were laterally displaced (Mean 14°), and symphyseal ends were medially displaced (Mean 1°). Movements were observed during jaw manipulation and analyzed with CT-images that confirmed quantitative inclinometer/accelerometer data, including the unstable intermediate (Phase 2) position. Together these shifting movements maintain a constant distance for adductor muscles stretched between the skull's temporal fossa and mandible's coronoid process. Mandibular rotation enlarges the buccal cavity's volume as much as 36%, likely to improve prey capture in rorqual lunge feeding; it may strengthen and stabilize jaw opening or closure, perhaps via a simple locking or unlocking mechanism. Rotated lips may brace baleen racks during filtration. Mandibular movements may serve a proprioceptive mechanosensory function, perhaps via the symphyseal organ, to guide prey engulfment and water expulsion for filtration.     

Identification and Molecular Analysis of Glycosaminoglycans in Cutaneous Lupus Erythematosus and Dermatomyositis

Glycosaminoglycans (GAGs), also known histologically as dermal mucin, accumulate in several inflammatory skin conditions. Because different GAG species have distinct immunologic effects, the authors examined two GAGs, hyaluronan (HA) and chondroitin sulfate (CS), using specific stains in cutaneous lupus erythematosus (CLE) and dermatomyositis (DM). In the dermis of one CLE subtype, tumid LE (TLE), they found only increased HA, but both HA and CS were significantly elevated in another CLE subtype, discoid LE (DLE). DM lesional dermis accumulated mainly CS but not HA. The authors then used glycomic gene expression microarrays to assess the expression of HA- and CS-related genes in CLE skin. Real-time quantitative PCR confirmed significantly increased expression of HAS2, CHSY1, and C4ST1 in the combined groups of CLE lesions (n = 8) compared to healthy controls (n = 4). Thus, the increase in HA in CLE presumably results from upregulation of HAS2, whereas CHSY1 and C4ST1 appear to contribute to increased CS. Based on their known immunomodulatory effects in other systems, HA and CS may thus participate in the pathophysiology of these inflammatory skin conditions.     

Landscape-level gene flow in Lobaria pulmonaria, an epiphytic lichen

Epiphytes are strongly affected by the population dynamics of their host trees. Owing to the spatio-temporal dynamics of host tree populations, substantial dispersal rates--corresponding to high levels of gene flow--are needed for populations to persist in a landscape. However, several epiphytic lichens have been suggested to be dispersal-limited, which leads to the expectation of low gene flow at the landscape scale. Here, we study landscape-level genetic structure and gene flow of a putatively dispersal-limited epiphytic lichen, Lobaria pulmonaria. The genetic structure of L. pulmonaria was quantified at three hierarchical levels, based on 923 thalli collected from 41 plots situated within a pasture-woodland landscape and genotyped at six fungal microsatellite loci. We found significant isolation by distance, and significant genetic differentiation both among sampling plots and among trees. Landscape configuration, i.e. the effect of a large open area separating two forested regions, did not leave a traceable pattern in genetic structure, as assessed with partial Mantel tests and analysis of molecular variance. Gene pools were spatially intermingled in the pasture-woodland landscape, as determined by Bayesian analysis of population structure. Evidence for local gene flow was found in a disturbed area that was mainly colonized from nearby sources. Our analyses indicated high rates of gene flow of L. pulmonaria among forest patches, which may reflect the historical connectedness of the landscape through gene movement. These results support the conclusion that dispersal in L. pulmonaria is rather effective, but not spatially unrestricted.     

Lichen endozoochory by snails

Endozoochory plays a prominent role for the dispersal of seed plants. However, for most other plant taxa it is not known whether this mode of dispersal occurs at all. Among those other taxa, lichens as symbiotic associations of algae and fungi are peculiar as their successful dispersal requires movement of propagules that leaves the symbiosis functional. However, the potential for endozoochorous dispersal of lichen fragments has been completely overlooked. We fed sterile thalli of two foliose lichen species (Lobaria pulmonaria and Physcia adscendens) differing in habitat and air-quality requirements to nine snail species common in temperate Europe. We demonstrated morphologically that L. pulmonaria regenerated from 29.0% of all 379 fecal pellets, whereas P. adscendens regenerated from 40.9% of all 433 fecal pellets, showing that lichen fragments survived gut passage of all snail species. Moreover, molecular analysis of regenerated lichens confirmed the species identity for a subset of samples. Regeneration rates were higher for the generalist lichen species P. adscendens than for the specialist lichen species L. pulmonaria. Furthermore, lichen regeneration rates varied among snail species with higher rates after gut passage of heavier snail species. We suggest that gastropods generally grazing on lichen communities are important, but so far completely overlooked, as vectors for lichen dispersal. This opens new ecological perspectives and questions the traditional view of an entirely antagonistic relationship between gastropods and lichens.     

Combination of Autoantibody Signature with PSA Level Enables a Highly Accurate Blood-Based Differentiation of Prostate Cancer Patients from Patients with Benign Prostatic Hyperplasia

Although an increased level of the prostate-specific antigen can be an indication for prostate cancer, other reasons often lead to a high rate of false positive results. Therefore, an additional serological screening of autoantibodies in patients’ sera could improve the detection of prostate cancer. We performed protein macroarray screening with sera from 49 prostate cancer patients, 70 patients with benign prostatic hyperplasia and 28 healthy controls and compared the autoimmune response in those groups. We were able to distinguish prostate cancer patients from normal controls with an accuracy of 83.2%, patients with benign prostatic hyperplasia from normal controls with an accuracy of 86.0% and prostate cancer patients from patients with benign prostatic hyperplasia with an accuracy of 70.3%. Combining seroreactivity pattern with a PSA level of higher than 4.0 ng/ml this classification could be improved to an accuracy of 84.1%. For selected proteins we were able to confirm the differential expression by using luminex on 84 samples. We provide a minimally invasive serological method to reduce false positive results in detection of prostate cancer and according to PSA screening to distinguish men with prostate cancer from men with benign prostatic hyperplasia.     

Purification of a myosin phosphatase from bovine aortic smooth muscle

A myosin phosphatase has been purified to homogeneity from bovine aortic smooth muscle. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis of the enzyme eluted from nondenaturing gels revealed two subunits (Mr = 67,000 and 38,000). Densitometric scans of the subunits indicated a molar ratio of 1:1. Several phosphoproteins were substrates for the phosphatase including histone II-A, isolated 20,000-dalton smooth muscle myosin light chains, phosphorylase a, and smooth muscle myosin. In the presence of 0.25 M NaCl and a substrate concentration of 2 microM, myosin was preferentially dephosphorylated. The specific activity of the phosphatase for myosin at a concentration of 10 microM was found to be 5 mumol/mg/min. The phosphatase required Mn2+ or Co2+ ions for activity. Mg2+, Ca2+, or Mg-ATP would not substitute for Mn2+ or Co2+ at equimolar concentrations. This phosphatase may play an important role in regulating actin-myosin interaction in smooth muscle by serving to dephosphorylate myosin.     

Circulating gonadotrophins during a period of restricted energy intake in relation to body condition in heifers.

Beef heifers, 13 months old, were fed to achieve high (7.6 +/- 0.2 units) or low (3.9 +/- 0.1 units) body condition by feeding them one of two diets for 20 weeks. During week 17 of the growth phase, all heifers were ovariectomized. From week 20 to week 27 (restriction phase), all heifers were fed a daily diet containing 0.071 MJ metabolizable energy kg-1 body weight. At weekly intervals throughout the restriction phase, blood samples were collected at 10-min intervals for 11 h to determine the pattern of secretion of luteinizing hormone (LH), the amount of LH released in response to 750 ng (pituitary responsiveness) and 50 micrograms LH-releasing hormone (LHRH, releasable stores) and mean concentrations of follicle-stimulating hormone (FSH) in the circulation. Body weight declined during the restriction phase in a similar fashion in heifers with high and low body condition and changes in body weight were unrelated to mean concentrations of LH and FSH and frequency of LH pulses. Amplitude of LH pulses and responsiveness to 750 ng LHRH increased in a linear fashion with weight loss in heifers with low but not in those with high body condition. The amount of LH released in response to 50 micrograms LHRH decreased with increasing weight loss in heifers with high but not with low body condition, indicating that releasable pools of LH declined with increased weight loss in heifers with high body condition.(ABSTRACT TRUNCATED AT 250 WORDS)